first commit

typo3/sysext/core/Classes/Authentication/AbstractAuthenticationService.php

@@ -0,0 +1,170 @@
+<?php
+namespace TYPO3\CMS\Core\Authentication;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Database\ConnectionPool;
+use TYPO3\CMS\Core\Database\Query\QueryHelper;
+use TYPO3\CMS\Core\Database\Query\Restriction\DeletedRestriction;
+use TYPO3\CMS\Core\Service\AbstractService;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * Authentication services class
+ */
+class AbstractAuthenticationService extends AbstractService
+{
+    /**
+     * User object
+     *
+     * @var AbstractUserAuthentication
+     */
+    public $pObj;
+
+    /**
+     * Subtype of the service which is used to call the service.
+     *
+     * @var string
+     */
+    public $mode;
+
+    /**
+     * Submitted login form data
+     *
+     * @var array
+     */
+    public $login = [];
+
+    /**
+     * Various data
+     *
+     * @var array
+     */
+    public $authInfo = [];
+
+    /**
+     * User db table definition
+     *
+     * @var array
+     */
+    public $db_user = [];
+
+    /**
+     * Usergroups db table definition
+     *
+     * @var array
+     */
+    public $db_groups = [];
+
+    /**
+     * If the writelog() functions is called if a login-attempt has be tried without success
+     *
+     * @var bool
+     */
+    public $writeAttemptLog = false;
+
+    /**
+     * Initialize authentication service
+     *
+     * @param string $mode Subtype of the service which is used to call the service.
+     * @param array $loginData Submitted login form data
+     * @param array $authInfo Information array. Holds submitted form data etc.
+     * @param AbstractUserAuthentication $pObj Parent object
+     */
+    public function initAuth($mode, $loginData, $authInfo, $pObj)
+    {
+        $this->pObj = $pObj;
+        // Sub type
+        $this->mode = $mode;
+        $this->login = $loginData;
+        $this->authInfo = $authInfo;
+        $this->db_user = $this->getServiceOption('db_user', $authInfo['db_user'] ?? [], false);
+        $this->db_groups = $this->getServiceOption('db_groups', $authInfo['db_groups'] ?? [], false);
+        $this->writeAttemptLog = $this->pObj->writeAttemptLog ?? true;
+    }
+
+    /**
+     * Check the login data with the user record data for builtin login methods
+     *
+     * @param array $user User data array
+     * @param array $loginData Login data array
+     * @param string $passwordCompareStrategy Password compare strategy
+     * @return bool TRUE if login data matched
+     * @deprecated since TYPO3 v9, will be removed in TYPO3 v10.0.
+     */
+    public function compareUident(array $user, array $loginData, $passwordCompareStrategy = '')
+    {
+        trigger_error('This method will be removed in TYPO3 v10.0.', E_USER_DEPRECATED);
+        return $this->pObj->compareUident($user, $loginData, $passwordCompareStrategy);
+    }
+
+    /**
+     * Writes to log database table in pObj
+     *
+     * @param int $type denotes which module that has submitted the entry. This is the current list:  1=tce_db; 2=tce_file; 3=system (eg. sys_history save); 4=modules; 254=Personal settings changed; 255=login / out action: 1=login, 2=logout, 3=failed login (+ errorcode 3), 4=failure_warning_email sent
+     * @param int $action denotes which specific operation that wrote the entry (eg. 'delete', 'upload', 'update' and so on...). Specific for each $type. Also used to trigger update of the interface. (see the log-module for the meaning of each number !!)
+     * @param int $error flag. 0 = message, 1 = error (user problem), 2 = System Error (which should not happen), 3 = security notice (admin)
+     * @param int $details_nr The message number. Specific for each $type and $action. in the future this will make it possible to translate error messages to other languages
+     * @param string $details Default text that follows the message
+     * @param array $data Data that follows the log. Might be used to carry special information. If an array the first 5 entries (0-4) will be sprintf'ed the details-text...
+     * @param string $tablename Special field used by tce_main.php. These ($tablename, $recuid, $recpid) holds the reference to the record which the log-entry is about. (Was used in attic status.php to update the interface.)
+     * @param int|string $recuid Special field used by tce_main.php. These ($tablename, $recuid, $recpid) holds the reference to the record which the log-entry is about. (Was used in attic status.php to update the interface.)
+     * @param int|string $recpid Special field used by tce_main.php. These ($tablename, $recuid, $recpid) holds the reference to the record which the log-entry is about. (Was used in attic status.php to update the interface.)
+     */
+    public function writelog($type, $action, $error, $details_nr, $details, $data, $tablename = '', $recuid = '', $recpid = '')
+    {
+        if ($this->writeAttemptLog) {
+            $this->pObj->writelog($type, $action, $error, $details_nr, $details, $data, $tablename, $recuid, $recpid);
+        }
+    }
+
+    /**
+     * Get a user from DB by username
+     *
+     * @param string $username User name
+     * @param string $extraWhere Additional WHERE clause: " AND ...
+     * @param array|string $dbUserSetup User db table definition, or empty string for $this->db_user
+     * @return mixed User array or FALSE
+     */
+    public function fetchUserRecord($username, $extraWhere = '', $dbUserSetup = '')
+    {
+        $dbUser = is_array($dbUserSetup) ? $dbUserSetup : $this->db_user;
+        $user = false;
+        if ($username || $extraWhere) {
+            $query = GeneralUtility::makeInstance(ConnectionPool::class)->getQueryBuilderForTable($dbUser['table']);
+            $query->getRestrictions()->removeAll()
+                ->add(GeneralUtility::makeInstance(DeletedRestriction::class));
+            $constraints = array_filter([
+                QueryHelper::stripLogicalOperatorPrefix($dbUser['check_pid_clause']),
+                QueryHelper::stripLogicalOperatorPrefix($dbUser['enable_clause']),
+                QueryHelper::stripLogicalOperatorPrefix($extraWhere),
+            ]);
+            if (!empty($username)) {
+                array_unshift(
+                    $constraints,
+                    $query->expr()->eq(
+                        $dbUser['username_column'],
+                        $query->createNamedParameter($username, \PDO::PARAM_STR)
+                    )
+                );
+            }
+            $user = $query->select('*')
+                ->from($dbUser['table'])
+                ->where(...$constraints)
+                ->execute()
+                ->fetch();
+        }
+        return $user;
+    }
+}

typo3/sysext/core/Classes/Authentication/AuthenticationService.php

@@ -0,0 +1,405 @@
+<?php
+namespace TYPO3\CMS\Core\Authentication;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Crypto\PasswordHashing\InvalidPasswordHashException;
+use TYPO3\CMS\Core\Crypto\PasswordHashing\PasswordHashFactory;
+use TYPO3\CMS\Core\Crypto\PasswordHashing\PasswordHashInterface;
+use TYPO3\CMS\Core\Database\Connection;
+use TYPO3\CMS\Core\Database\ConnectionPool;
+use TYPO3\CMS\Core\Database\Query\Restriction\HiddenRestriction;
+use TYPO3\CMS\Core\TimeTracker\TimeTracker;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * Authentication services class
+ */
+class AuthenticationService extends AbstractAuthenticationService
+{
+    /**
+     * Process the submitted credentials.
+     * In this case hash the clear text password if it has been submitted.
+     *
+     * @param array $loginData Credentials that are submitted and potentially modified by other services
+     * @param string $passwordTransmissionStrategy Keyword of how the password has been hashed or encrypted before submission
+     * @return bool
+     */
+    public function processLoginData(array &$loginData, $passwordTransmissionStrategy)
+    {
+        $isProcessed = false;
+        if ($passwordTransmissionStrategy === 'normal') {
+            $loginData['uident_text'] = $loginData['uident'];
+            $isProcessed = true;
+        }
+        return $isProcessed;
+    }
+
+    /**
+     * Find a user (eg. look up the user record in database when a login is sent)
+     *
+     * @return mixed User array or FALSE
+     */
+    public function getUser()
+    {
+        if ($this->login['status'] !== LoginType::LOGIN) {
+            return false;
+        }
+        if ((string)$this->login['uident_text'] === '') {
+            // Failed Login attempt (no password given)
+            $this->writelog(255, 3, 3, 2, 'Login-attempt from ###IP### for username \'%s\' with an empty password!', [
+                $this->login['uname']
+            ]);
+            $this->logger->warning(sprintf('Login-attempt from %s, for username \'%s\' with an empty password!', $this->authInfo['REMOTE_ADDR'], $this->login['uname']));
+            return false;
+        }
+
+        $user = $this->fetchUserRecord($this->login['uname']);
+        if (!is_array($user)) {
+            // Failed login attempt (no username found)
+            $this->writelog(255, 3, 3, 2, 'Login-attempt from ###IP###, username \'%s\' not found!!', [$this->login['uname']]);
+            $this->logger->info('Login-attempt from username \'' . $this->login['uname'] . '\' not found!', [
+                'REMOTE_ADDR' => $this->authInfo['REMOTE_ADDR']
+            ]);
+        } else {
+            $this->logger->debug('User found', [
+                $this->db_user['userid_column'] => $user[$this->db_user['userid_column']],
+                $this->db_user['username_column'] => $user[$this->db_user['username_column']]
+            ]);
+        }
+        return $user;
+    }
+
+    /**
+     * Authenticate a user: Check submitted user credentials against stored hashed password,
+     * check domain lock if configured.
+     *
+     * Returns one of the following status codes:
+     *  >= 200: User authenticated successfully. No more checking is needed by other auth services.
+     *  >= 100: User not authenticated; this service is not responsible. Other auth services will be asked.
+     *  > 0:    User authenticated successfully. Other auth services will still be asked.
+     *  <= 0:   Authentication failed, no more checking needed by other auth services.
+     *
+     * @param array $user User data
+     * @return int Authentication status code, one of 0, 100, 200
+     */
+    public function authUser(array $user): int
+    {
+        // Early 100 "not responsible, check other services" if username or password is empty
+        if (!isset($this->login['uident_text']) || (string)$this->login['uident_text'] === ''
+            || !isset($this->login['uname']) || (string)$this->login['uname'] === '') {
+            return 100;
+        }
+
+        if (empty($this->db_user['table'])) {
+            throw new \RuntimeException('User database table not set', 1533159150);
+        }
+
+        $submittedUsername = (string)$this->login['uname'];
+        $submittedPassword = (string)$this->login['uident_text'];
+        $passwordHashInDatabase = $user['password'];
+        $queriedDomain = $this->authInfo['HTTP_HOST'];
+        $configuredDomainLock = $user['lockToDomain'];
+        $userDatabaseTable = $this->db_user['table'];
+
+        $isSaltedPassword = false;
+        $isValidPassword = false;
+        $isReHashNeeded = false;
+        $isDomainLockMet = false;
+
+        $saltFactory = GeneralUtility::makeInstance(PasswordHashFactory::class);
+
+        // Get a hashed password instance for the hash stored in db of this user
+        $invalidPasswordHashException = null;
+        try {
+            $hashInstance = $saltFactory->get($passwordHashInDatabase, TYPO3_MODE);
+        } catch (InvalidPasswordHashException $invalidPasswordHashException) {
+            // This can be refactored if the 'else' part below is gone in TYPO3 v10.0: Log and return 100 here
+            $hashInstance = null;
+        }
+        // An instance of the currently configured salted password mechanism
+        // Don't catch InvalidPasswordHashException here: Only install tool should handle those configuration failures
+        $defaultHashInstance = $saltFactory->getDefaultHashInstance(TYPO3_MODE);
+
+        if ($hashInstance instanceof PasswordHashInterface) {
+            // We found a hash class that can handle this type of hash
+            $isSaltedPassword = true;
+            $isValidPassword = $hashInstance->checkPassword($submittedPassword, $passwordHashInDatabase);
+            if ($isValidPassword) {
+                if ($hashInstance->isHashUpdateNeeded($passwordHashInDatabase)
+                    || $defaultHashInstance != $hashInstance
+                ) {
+                    // Lax object comparison intended: Rehash if old and new salt objects are not
+                    // instances of the same class.
+                    $isReHashNeeded = true;
+                }
+                if (empty($configuredDomainLock)) {
+                    // No domain restriction set for user in db. This is ok.
+                    $isDomainLockMet = true;
+                } elseif (!strcasecmp($configuredDomainLock, $queriedDomain)) {
+                    // Domain restriction set and it matches given host. Ok.
+                    $isDomainLockMet = true;
+                }
+            }
+        } elseif (substr($user['password'], 0, 2) === 'M$') {
+            // @todo @deprecated: The entire else should be removed in TYPO3 v10.0 as dedicated breaking patch
+            // If the stored db password starts with M$, it may be a md5 password that has been
+            // upgraded to a salted md5 using the old salted passwords scheduler task.
+            // See if a salt instance is returned if we cut off the M, so Md5PasswordHash kicks in
+            try {
+                $hashInstance = $saltFactory->get(substr($passwordHashInDatabase, 1), TYPO3_MODE);
+                $isSaltedPassword = true;
+                $isValidPassword = $hashInstance->checkPassword(md5($submittedPassword), substr($passwordHashInDatabase, 1));
+                if ($isValidPassword) {
+                    // Upgrade this password to a sane mechanism now
+                    $isReHashNeeded = true;
+                    if (empty($configuredDomainLock)) {
+                        // No domain restriction set for user in db. This is ok.
+                        $isDomainLockMet = true;
+                    } elseif (!strcasecmp($configuredDomainLock, $queriedDomain)) {
+                        // Domain restriction set and it matches given host. Ok.
+                        $isDomainLockMet = true;
+                    }
+                }
+            } catch (InvalidPasswordHashException $e) {
+                // Still no instance found: $isSaltedPasswords is NOT set to true, logging and return done below
+            }
+        } else {
+            // @todo: Simplify if elseif part is gone
+            // Still no valid hash instance could be found. Probably the stored hash used a mechanism
+            // that is not available on current system. We throw the previous exception again to be
+            // handled on a higher level.
+            if ($invalidPasswordHashException !== null) {
+                throw $invalidPasswordHashException;
+            }
+        }
+
+        if (!$isSaltedPassword) {
+            // Could not find a responsible hash algorithm for given password. This is unusual since other
+            // authentication services would usually be called before this one with higher priority. We thus log
+            // the failed login but still return '100' to proceed with other services that may follow.
+            $message = 'Login-attempt from ###IP###, username \'%s\', no suitable hash method found!';
+            $this->writeLogMessage($message, $submittedUsername);
+            $this->writelog(255, 3, 3, 1, $message, [$submittedUsername]);
+            // Not responsible, check other services
+            return 100;
+        }
+
+        if (!$isValidPassword) {
+            // Failed login attempt - wrong password
+            $message = 'Login-attempt from ###IP###, username \'%s\', password not accepted!';
+            $this->writeLogMessage($message, $submittedUsername);
+            $this->writelog(255, 3, 3, 1, $message, [$submittedUsername]);
+            // Responsible, authentication failed, do NOT check other services
+            return 0;
+        }
+
+        if (!$isDomainLockMet) {
+            // Password ok, but configured domain lock not met
+            $errorMessage = 'Login-attempt from ###IP###, username \'%s\', locked domain \'%s\' did not match \'%s\'!';
+            $this->writeLogMessage($errorMessage, $user[$this->db_user['username_column']], $configuredDomainLock, $queriedDomain);
+            $this->writelog(255, 3, 3, 1, $errorMessage, [$user[$this->db_user['username_column']], $configuredDomainLock, $queriedDomain]);
+            // Responsible, authentication ok, but domain lock not ok, do NOT check other services
+            return 0;
+        }
+
+        if ($isReHashNeeded) {
+            // Given password validated but a re-hash is needed. Do so.
+            $this->updatePasswordHashInDatabase(
+                $userDatabaseTable,
+                (int)$user['uid'],
+                $defaultHashInstance->getHashedPassword($submittedPassword)
+            );
+        }
+
+        // Responsible, authentication ok, domain lock ok. Log successful login and return 'auth ok, do NOT check other services'
+        $this->writeLogMessage(TYPO3_MODE . ' Authentication successful for username \'%s\'', $submittedUsername);
+        return 200;
+    }
+
+    /**
+     * Find usergroup records, currently only for frontend
+     *
+     * @param array $user Data of user.
+     * @param array $knownGroups Group data array of already known groups. This is handy if you want select other related groups. Keys in this array are unique IDs of those groups.
+     * @return mixed Groups array, keys = uid which must be unique
+     */
+    public function getGroups($user, $knownGroups)
+    {
+        // Attention: $knownGroups is not used within this method, but other services can use it.
+        // This parameter should not be removed!
+        // The FrontendUserAuthentication call getGroups and handover the previous detected groups.
+        $groupDataArr = [];
+        if ($this->mode === 'getGroupsFE') {
+            $groups = [];
+            if ($user[$this->db_user['usergroup_column']] ?? false) {
+                $groupList = $user[$this->db_user['usergroup_column']];
+                $groups = [];
+                $this->getSubGroups($groupList, '', $groups);
+            }
+            // ADD group-numbers if the IPmask matches.
+            foreach ($GLOBALS['TYPO3_CONF_VARS']['FE']['IPmaskMountGroups'] ?? [] as $IPel) {
+                if ($this->authInfo['REMOTE_ADDR'] && $IPel[0] && GeneralUtility::cmpIP($this->authInfo['REMOTE_ADDR'], $IPel[0])) {
+                    $groups[] = (int)$IPel[1];
+                }
+            }
+            $groups = array_unique($groups);
+            if (!empty($groups)) {
+                $this->logger->debug('Get usergroups with id: ' . implode(',', $groups));
+                $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)
+                    ->getQueryBuilderForTable($this->db_groups['table']);
+                if (!empty($this->authInfo['showHiddenRecords'])) {
+                    $queryBuilder->getRestrictions()->removeByType(HiddenRestriction::class);
+                }
+
+                $res = $queryBuilder->select('*')
+                    ->from($this->db_groups['table'])
+                    ->where(
+                        $queryBuilder->expr()->in(
+                            'uid',
+                            $queryBuilder->createNamedParameter($groups, Connection::PARAM_INT_ARRAY)
+                        ),
+                        $queryBuilder->expr()->orX(
+                            $queryBuilder->expr()->eq(
+                                'lockToDomain',
+                                $queryBuilder->createNamedParameter('', \PDO::PARAM_STR)
+                            ),
+                            $queryBuilder->expr()->isNull('lockToDomain'),
+                            $queryBuilder->expr()->eq(
+                                'lockToDomain',
+                                $queryBuilder->createNamedParameter($this->authInfo['HTTP_HOST'], \PDO::PARAM_STR)
+                            )
+                        )
+                    )
+                    ->execute();
+
+                while ($row = $res->fetch()) {
+                    $groupDataArr[$row['uid']] = $row;
+                }
+            } else {
+                $this->logger->debug('No usergroups found.');
+            }
+        }
+        return $groupDataArr;
+    }
+
+    /**
+     * Fetches subgroups of groups. Function is called recursively for each subgroup.
+     * Function was previously copied from
+     * \TYPO3\CMS\Core\Authentication\BackendUserAuthentication->fetchGroups and has been slightly modified.
+     *
+     * @param string $grList Commalist of fe_groups uid numbers
+     * @param string $idList List of already processed fe_groups-uids so the function will not fall into an eternal recursion.
+     * @param array $groups
+     * @internal
+     */
+    public function getSubGroups($grList, $idList, &$groups)
+    {
+        // Fetching records of the groups in $grList (which are not blocked by lockedToDomain either):
+        $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)->getQueryBuilderForTable('fe_groups');
+        if (!empty($this->authInfo['showHiddenRecords'])) {
+            $queryBuilder->getRestrictions()->removeByType(HiddenRestriction::class);
+        }
+
+        $res = $queryBuilder
+            ->select('uid', 'subgroup')
+            ->from($this->db_groups['table'])
+            ->where(
+                $queryBuilder->expr()->in(
+                    'uid',
+                    $queryBuilder->createNamedParameter(
+                        GeneralUtility::intExplode(',', $grList, true),
+                        Connection::PARAM_INT_ARRAY
+                    )
+                ),
+                $queryBuilder->expr()->orX(
+                    $queryBuilder->expr()->eq(
+                        'lockToDomain',
+                        $queryBuilder->createNamedParameter('', \PDO::PARAM_STR)
+                    ),
+                    $queryBuilder->expr()->isNull('lockToDomain'),
+                    $queryBuilder->expr()->eq(
+                        'lockToDomain',
+                        $queryBuilder->createNamedParameter($this->authInfo['HTTP_HOST'], \PDO::PARAM_STR)
+                    )
+                )
+            )
+            ->execute();
+
+        // Internal group record storage
+        $groupRows = [];
+        // The groups array is filled
+        while ($row = $res->fetch()) {
+            if (!in_array($row['uid'], $groups)) {
+                $groups[] = $row['uid'];
+            }
+            $groupRows[$row['uid']] = $row;
+        }
+        // Traversing records in the correct order
+        $include_staticArr = GeneralUtility::intExplode(',', $grList);
+        // traversing list
+        foreach ($include_staticArr as $uid) {
+            // Get row:
+            $row = $groupRows[$uid];
+            // Must be an array and $uid should not be in the idList, because then it is somewhere previously in the grouplist
+            if (is_array($row) && !GeneralUtility::inList($idList, $uid) && trim($row['subgroup'])) {
+                // Make integer list
+                $theList = implode(',', GeneralUtility::intExplode(',', $row['subgroup']));
+                // Call recursively, pass along list of already processed groups so they are not processed again.
+                $this->getSubGroups($theList, $idList . ',' . $uid, $groups);
+            }
+        }
+    }
+
+    /**
+     * Method updates a FE/BE user record - in this case a new password string will be set.
+     *
+     * @param string $table Database table of this user, usually 'be_users' or 'fe_users'
+     * @param int $uid uid of user record that will be updated
+     * @param string $newPassword Field values as key=>value pairs to be updated in database
+     */
+    protected function updatePasswordHashInDatabase(string $table, int $uid, string $newPassword): void
+    {
+        $connection = GeneralUtility::makeInstance(ConnectionPool::class)->getConnectionForTable($table);
+        $connection->update(
+            $table,
+            ['password' => $newPassword],
+            ['uid' => $uid]
+        );
+        $this->logger->notice('Automatic password update for user record in ' . $table . ' with uid ' . $uid);
+    }
+
+    /**
+     * Writes log message. Destination log depends on the current system mode.
+     *
+     * This function accepts variable number of arguments and can format
+     * parameters. The syntax is the same as for sprintf()
+     * If a marker ###IP### is present in the message, it is automatically replaced with the REMOTE_ADDR
+     *
+     * @param string $message Message to output
+     * @param array<int, mixed> $params
+     */
+    protected function writeLogMessage(string $message, ...$params): void
+    {
+        if (!empty($params)) {
+            $message = vsprintf($message, $params);
+        }
+        $message = str_replace('###IP###', (string)GeneralUtility::getIndpEnv('REMOTE_ADDR'), $message);
+        if (TYPO3_MODE === 'FE') {
+            $timeTracker = GeneralUtility::makeInstance(TimeTracker::class);
+            $timeTracker->setTSlogMessage($message);
+        }
+        $this->logger->notice($message);
+    }
+}

typo3/sysext/core/Classes/Authentication/CommandLineUserAuthentication.php

@@ -0,0 +1,176 @@
+<?php
+namespace TYPO3\CMS\Core\Authentication;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Core\Environment;
+use TYPO3\CMS\Core\Crypto\PasswordHashing\PasswordHashFactory;
+use TYPO3\CMS\Core\Crypto\Random;
+use TYPO3\CMS\Core\Database\ConnectionPool;
+use TYPO3\CMS\Core\Database\Query\Restriction\DeletedRestriction;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * TYPO3 backend user authentication on a CLI level
+ * Auto-logs in, only allowed on CLI
+ */
+class CommandLineUserAuthentication extends BackendUserAuthentication
+{
+
+    /**
+     * The username of the CLI user (there is only one)
+     * @var string
+     */
+    protected $username = '_cli_';
+
+    /**
+     * Constructor, only allowed in CLI mode
+     *
+     * @throws \RuntimeException
+     */
+    public function __construct()
+    {
+        if (!Environment::isCli()) {
+            throw new \RuntimeException('Creating a CLI-based user object on non-CLI level is not allowed', 1483971165);
+        }
+        if (!$this->isUserAllowedToLogin()) {
+            throw new \RuntimeException('Login Error: TYPO3 is in maintenance mode at the moment. Only administrators are allowed access.', 1483971855);
+        }
+        $this->dontSetCookie = true;
+        parent::__construct();
+    }
+
+    /**
+     * Replacement for AbstactUserAuthentication::start()
+     *
+     * We do not need support for sessions, cookies, $_GET-modes, the postUserLookup hook or
+     * a database connectiona during CLI Bootstrap
+     */
+    public function start()
+    {
+        $this->logger->debug('## Beginning of auth logging.');
+        // svConfig is unused, but we set it, as the property is public and might be used by extensions
+        $this->svConfig = $GLOBALS['TYPO3_CONF_VARS']['SVCONF']['auth'] ?? [];
+    }
+
+    /**
+     * Replacement for AbstactUserAuthentication::checkAuthentication()
+     *
+     * Not required in CLI mode, therefore empty.
+     */
+    public function checkAuthentication()
+    {
+    }
+
+    /**
+     * Logs-in the _CLI_ user. It does not need to check for credentials.
+     *
+     * @throws \RuntimeException when the user could not log in or it is an admin
+     */
+    public function authenticate()
+    {
+        // check if a _CLI_ user exists, if not, create one
+        $this->setBeUserByName($this->username);
+        if (!$this->user['uid']) {
+            // create a new BE user in the database
+            if (!$this->checkIfCliUserExists()) {
+                $this->createCliUser();
+            } else {
+                throw new \RuntimeException('No backend user named "_cli_" could be authenticated, maybe this user is "hidden"?', 1484050401);
+            }
+            $this->setBeUserByName($this->username);
+        }
+        if (!$this->user['uid']) {
+            throw new \RuntimeException('No backend user named "_cli_" could be created.', 1476107195);
+        }
+        // The groups are fetched and ready for permission checking in this initialization.
+        $this->fetchGroupData();
+        $this->backendSetUC();
+        // activate this functionality for DataHandler
+        $this->uc['recursiveDelete'] = true;
+    }
+
+    /**
+     * Logs in the TYPO3 Backend user "_cli_"
+     *
+     * @param bool $proceedIfNoUserIsLoggedIn if this option is set, then there won't be a redirect to the login screen of the Backend - used for areas in the backend which do not need user rights like the login page.
+     */
+    public function backendCheckLogin($proceedIfNoUserIsLoggedIn = false)
+    {
+        $this->authenticate();
+    }
+
+    /**
+     * Determines whether a CLI backend user is allowed to access TYPO3.
+     * Only when adminOnly is off (=0), and only allowed for admins and CLI users (=2)
+     *
+     * @return bool Whether the CLI user is allowed to access TYPO3
+     */
+    protected function isUserAllowedToLogin()
+    {
+        return in_array((int)$GLOBALS['TYPO3_CONF_VARS']['BE']['adminOnly'], [0, 2], true);
+    }
+
+    /**
+     * Check if a user with username "_cli_" exists. Deleted users are left out
+     * but hidden and start / endtime restricted users are considered.
+     *
+     * @return bool true if the user exists
+     */
+    protected function checkIfCliUserExists()
+    {
+        $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)->getQueryBuilderForTable('be_users');
+        $queryBuilder->getRestrictions()
+            ->removeAll()
+            ->add(GeneralUtility::makeInstance(DeletedRestriction::class));
+        $count = $queryBuilder
+            ->count('*')
+            ->from('be_users')
+            ->where($queryBuilder->expr()->eq('username', $queryBuilder->createNamedParameter('_cli_')))
+            ->execute()
+            ->fetchColumn(0);
+        return (bool)$count;
+    }
+
+    /**
+     * Create a record in the DB table be_users called "_cli_" with no other information
+     */
+    protected function createCliUser()
+    {
+        $userFields = [
+            'username' => $this->username,
+            'password' => $this->generateHashedPassword(),
+            'admin'    => 1,
+            'tstamp'   => $GLOBALS['EXEC_TIME'],
+            'crdate'   => $GLOBALS['EXEC_TIME']
+        ];
+
+        $databaseConnection = GeneralUtility::makeInstance(ConnectionPool::class)
+            ->getConnectionForTable('be_users');
+        $databaseConnection->insert('be_users', $userFields);
+    }
+
+    /**
+     * This function returns a salted hashed key.
+     *
+     * @return string a random password
+     */
+    protected function generateHashedPassword()
+    {
+        $cryptoService = GeneralUtility::makeInstance(Random::class);
+        $password = $cryptoService->generateRandomBytes(20);
+        $hashInstance = GeneralUtility::makeInstance(PasswordHashFactory::class)->getDefaultHashInstance('BE');
+        return $hashInstance->getHashedPassword($password);
+    }
+}

typo3/sysext/core/Classes/Authentication/LoginType.php

@@ -0,0 +1,35 @@
+<?php
+declare(strict_types = 1);
+
+namespace TYPO3\CMS\Core\Authentication;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Type\Enumeration;
+
+/**
+ * Contains the different login types
+ */
+final class LoginType extends Enumeration
+{
+    /**
+     * When a login is in process
+     */
+    public const LOGIN = 'login';
+
+    /**
+     * When a logout is in process
+     */
+    public const LOGOUT = 'logout';
+}

typo3/sysext/core/Classes/Cache/Backend/AbstractBackend.php

@@ -0,0 +1,147 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Backend;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use Psr\Log\LoggerAwareInterface;
+use Psr\Log\LoggerAwareTrait;
+use TYPO3\CMS\Core\Log\LogManager;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * An abstract caching backend
+ */
+abstract class AbstractBackend implements BackendInterface, LoggerAwareInterface
+{
+    use LoggerAwareTrait;
+
+    const DATETIME_EXPIRYTIME_UNLIMITED = '9999-12-31T23:59:59+0000';
+    const UNLIMITED_LIFETIME = 0;
+    /**
+     * Reference to the cache which uses this backend
+     *
+     * @var \TYPO3\CMS\Core\Cache\Frontend\FrontendInterface
+     */
+    protected $cache;
+
+    /**
+     * @var string
+     */
+    protected $cacheIdentifier;
+
+    /**
+     * The current application context
+     *
+     * This variable is currently unused and set to "production" always.
+     * It is only kept to keep backwards compatibility.
+     *
+     * @var string
+     */
+    protected $context;
+
+    /**
+     * Default lifetime of a cache entry in seconds
+     *
+     * @var int
+     */
+    protected $defaultLifetime = 3600;
+
+    /**
+     * Constructs this backend
+     *
+     * @param string $context Unused, for backward compatibility only
+     * @param array $options Configuration options - depends on the actual backend
+     * @throws \InvalidArgumentException
+     */
+    public function __construct($context, array $options = [])
+    {
+        $this->context = $context;
+        if (is_array($options) || $options instanceof \ArrayAccess) {
+            foreach ($options as $optionKey => $optionValue) {
+                $methodName = 'set' . ucfirst($optionKey);
+                if (method_exists($this, $methodName)) {
+                    $this->{$methodName}($optionValue);
+                } else {
+                    throw new \InvalidArgumentException('Invalid cache backend option "' . $optionKey . '" for backend of type "' . static::class . '"', 1231267498);
+                }
+            }
+        }
+        if ($this->logger === null) {
+            $this->setLogger(
+                GeneralUtility::makeInstance(LogManager::class)
+                    ->getLogger(static::class)
+            );
+        }
+    }
+
+    /**
+     * Sets a reference to the cache frontend which uses this backend
+     *
+     * @param \TYPO3\CMS\Core\Cache\Frontend\FrontendInterface $cache The frontend for this backend
+     */
+    public function setCache(\TYPO3\CMS\Core\Cache\Frontend\FrontendInterface $cache)
+    {
+        $this->cache = $cache;
+        $this->cacheIdentifier = $this->cache->getIdentifier();
+    }
+
+    /**
+     * Sets the default lifetime for this cache backend
+     *
+     * @param int $defaultLifetime Default lifetime of this cache backend in seconds. If NULL is specified, the default lifetime is used. "0" means unlimited lifetime.
+     * @throws \InvalidArgumentException
+     */
+    public function setDefaultLifetime($defaultLifetime)
+    {
+        if (!is_int($defaultLifetime) || $defaultLifetime < 0) {
+            throw new \InvalidArgumentException('The default lifetime must be given as a positive integer.', 1233072774);
+        }
+        $this->defaultLifetime = $defaultLifetime;
+    }
+
+    /**
+     * Backwards compatibility safeguard since re-introducing flushByTags as API.
+     * See https://review.typo3.org/#/c/50537/ comments for patch set 14.
+     *
+     * The method is here even though it is only required for TaggableBackendInterface.
+     * We add it here to ensure third party cache backends do not fail but instead
+     * delegate to a less efficient linear flushing behavior.
+     *
+     * @param string[] $tags
+     */
+    public function flushByTags(array $tags)
+    {
+        array_walk($tags, [$this, 'flushByTag']);
+    }
+
+    /**
+     * Calculates the expiry time by the given lifetime. If no lifetime is
+     * specified, the default lifetime is used.
+     *
+     * @param int $lifetime The lifetime in seconds
+     * @return \DateTime The expiry time
+     */
+    protected function calculateExpiryTime($lifetime = null)
+    {
+        if ($lifetime === self::UNLIMITED_LIFETIME || $lifetime === null && $this->defaultLifetime === self::UNLIMITED_LIFETIME) {
+            $expiryTime = new \DateTime(self::DATETIME_EXPIRYTIME_UNLIMITED, new \DateTimeZone('UTC'));
+        } else {
+            if ($lifetime === null) {
+                $lifetime = $this->defaultLifetime;
+            }
+            $expiryTime = new \DateTime('now +' . $lifetime . ' seconds', new \DateTimeZone('UTC'));
+        }
+        return $expiryTime;
+    }
+}

typo3/sysext/core/Classes/Cache/Backend/ApcBackend.php

@@ -0,0 +1,308 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Backend;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Cache\Exception;
+use TYPO3\CMS\Core\Cache\Exception\InvalidDataException;
+use TYPO3\CMS\Core\Cache\Frontend\FrontendInterface;
+use TYPO3\CMS\Core\Core\Environment;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * A caching backend which stores cache entries by using APC.
+ *
+ * This backend uses the following types of keys:
+ * - tag_xxx
+ * xxx is tag name, value is array of associated identifiers identifier. This
+ * is "forward" tag index. It is mainly used for obtaining content by tag
+ * (get identifier by tag -> get content by identifier)
+ * - ident_xxx
+ * xxx is identifier, value is array of associated tags. This is "reverse" tag
+ * index. It provides quick access for all tags associated with this identifier
+ * and used when removing the identifier
+ *
+ * Each key is prepended with a prefix. By default prefix consists from two parts
+ * separated by underscore character and ends in yet another underscore character:
+ * - "TYPO3"
+ * - MD5 of path to TYPO3 project folder and user running TYPO3
+ * This prefix makes sure that keys from the different installations do not
+ * conflict.
+ */
+class ApcBackend extends AbstractBackend implements TaggableBackendInterface
+{
+    /**
+     * A prefix to separate stored data from other data possible stored in the APC
+     *
+     * @var string
+     */
+    protected $identifierPrefix;
+
+    /**
+     * Set the cache identifier prefix.
+     *
+     * @param string $identifierPrefix
+     */
+    protected function setIdentifierPrefix($identifierPrefix)
+    {
+        $this->identifierPrefix = $identifierPrefix;
+    }
+
+    /**
+     * Retrieves the cache identifier prefix.
+     *
+     * @return string
+     */
+    protected function getIdentifierPrefix()
+    {
+        return $this->identifierPrefix;
+    }
+
+    /**
+     * Constructs this backend
+     *
+     * @param string $context Unused, for backward compatibility only
+     * @param array $options Configuration options - unused here
+     * @throws Exception
+     */
+    public function __construct($context, array $options = [])
+    {
+        if (!extension_loaded('apc')) {
+            throw new Exception('The PHP extension "apc" or "apcu" must be installed and loaded in order to use the APC backend.', 1232985414);
+        }
+        if (PHP_SAPI === 'cli' && ini_get('apc.enable_cli') == 0) {
+            throw new Exception('The APC backend cannot be used because apc is disabled on CLI.', 1232985415);
+        }
+        parent::__construct($context, $options);
+    }
+
+    /**
+     * Initializes the identifier prefix when setting the cache.
+     *
+     * @param FrontendInterface $cache
+     */
+    public function setCache(FrontendInterface $cache)
+    {
+        parent::setCache($cache);
+        $processUser = $this->getCurrentUserData();
+        $pathHash = GeneralUtility::shortMD5(Environment::getProjectPath() . $processUser['name'] . $this->context . $cache->getIdentifier(), 12);
+        $this->setIdentifierPrefix('TYPO3_' . $pathHash);
+    }
+
+    /**
+     * Returns the current user data with posix_getpwuid or a default structure when
+     * posix_getpwuid is not available.
+     *
+     * @return array
+     */
+    protected function getCurrentUserData()
+    {
+        return extension_loaded('posix') ? posix_getpwuid(posix_geteuid()) : ['name' => 'default'];
+    }
+
+    /**
+     * Saves data in the cache.
+     *
+     * @param string $entryIdentifier An identifier for this specific cache entry
+     * @param string $data The data to be stored
+     * @param array $tags Tags to associate with this cache entry
+     * @param int $lifetime Lifetime of this cache entry in seconds. If NULL is specified, the default lifetime is used. "0" means unlimited lifetime.
+     * @throws Exception if no cache frontend has been set.
+     * @throws InvalidDataException if $data is not a string
+     */
+    public function set($entryIdentifier, $data, array $tags = [], $lifetime = null)
+    {
+        if (!$this->cache instanceof FrontendInterface) {
+            throw new Exception('No cache frontend has been set yet via setCache().', 1232986818);
+        }
+        if (!is_string($data)) {
+            throw new InvalidDataException('The specified data is of type "' . gettype($data) . '" but a string is expected.', 1232986825);
+        }
+        $tags[] = '%APCBE%' . $this->cacheIdentifier;
+        $expiration = $lifetime ?? $this->defaultLifetime;
+        $success = apc_store($this->getIdentifierPrefix() . $entryIdentifier, $data, $expiration);
+        if ($success === true) {
+            $this->removeIdentifierFromAllTags($entryIdentifier);
+            $this->addIdentifierToTags($entryIdentifier, $tags);
+        } else {
+            $this->logger->alert('Error using APCu: Could not save data in the cache.');
+        }
+    }
+
+    /**
+     * Loads data from the cache.
+     *
+     * @param string $entryIdentifier An identifier which describes the cache entry to load
+     * @return mixed The cache entry's content as a string or FALSE if the cache entry could not be loaded
+     */
+    public function get($entryIdentifier)
+    {
+        $success = false;
+        $value = apc_fetch($this->getIdentifierPrefix() . $entryIdentifier, $success);
+        return $success ? $value : $success;
+    }
+
+    /**
+     * Checks if a cache entry with the specified identifier exists.
+     *
+     * @param string $entryIdentifier An identifier specifying the cache entry
+     * @return bool TRUE if such an entry exists, FALSE if not
+     */
+    public function has($entryIdentifier)
+    {
+        $success = false;
+        apc_fetch($this->getIdentifierPrefix() . $entryIdentifier, $success);
+        return $success;
+    }
+
+    /**
+     * Removes all cache entries matching the specified identifier.
+     * Usually this only affects one entry but if - for what reason ever -
+     * old entries for the identifier still exist, they are removed as well.
+     *
+     * @param string $entryIdentifier Specifies the cache entry to remove
+     * @return bool TRUE if (at least) an entry could be removed or FALSE if no entry was found
+     */
+    public function remove($entryIdentifier)
+    {
+        $this->removeIdentifierFromAllTags($entryIdentifier);
+        return apc_delete($this->getIdentifierPrefix() . $entryIdentifier);
+    }
+
+    /**
+     * Finds and returns all cache entry identifiers which are tagged by the
+     * specified tag.
+     *
+     * @param string $tag The tag to search for
+     * @return array An array with identifiers of all matching entries. An empty array if no entries matched
+     */
+    public function findIdentifiersByTag($tag)
+    {
+        $success = false;
+        $identifiers = apc_fetch($this->getIdentifierPrefix() . 'tag_' . $tag, $success);
+        if ($success === false) {
+            return [];
+        }
+        return (array)$identifiers;
+    }
+
+    /**
+     * Finds all tags for the given identifier. This function uses reverse tag
+     * index to search for tags.
+     *
+     * @param string $identifier Identifier to find tags by
+     * @return array Array with tags
+     */
+    protected function findTagsByIdentifier($identifier)
+    {
+        $success = false;
+        $tags = apc_fetch($this->getIdentifierPrefix() . 'ident_' . $identifier, $success);
+        return $success ? (array)$tags : [];
+    }
+
+    /**
+     * Removes all cache entries of this cache.
+     *
+     * @throws Exception
+     */
+    public function flush()
+    {
+        if (!$this->cache instanceof FrontendInterface) {
+            throw new Exception('Yet no cache frontend has been set via setCache().', 1232986971);
+        }
+        $this->flushByTag('%APCBE%' . $this->cacheIdentifier);
+    }
+
+    /**
+     * Removes all cache entries of this cache which are tagged by the specified tag.
+     *
+     * @param string $tag The tag the entries must have
+     */
+    public function flushByTag($tag)
+    {
+        $identifiers = $this->findIdentifiersByTag($tag);
+        foreach ($identifiers as $identifier) {
+            $this->remove($identifier);
+        }
+    }
+
+    /**
+     * Associates the identifier with the given tags
+     *
+     * @param string $entryIdentifier
+     * @param array $tags
+     */
+    protected function addIdentifierToTags($entryIdentifier, array $tags)
+    {
+        // Get identifier-to-tag index to look for updates
+        $existingTags = $this->findTagsByIdentifier($entryIdentifier);
+        $existingTagsUpdated = false;
+
+        foreach ($tags as $tag) {
+            // Update tag-to-identifier index
+            $identifiers = $this->findIdentifiersByTag($tag);
+            if (!in_array($entryIdentifier, $identifiers, true)) {
+                $identifiers[] = $entryIdentifier;
+                apc_store($this->getIdentifierPrefix() . 'tag_' . $tag, $identifiers);
+            }
+            // Test if identifier-to-tag index needs update
+            if (!in_array($tag, $existingTags, true)) {
+                $existingTags[] = $tag;
+                $existingTagsUpdated = true;
+            }
+        }
+
+        // Update identifier-to-tag index if needed
+        if ($existingTagsUpdated) {
+            apc_store($this->getIdentifierPrefix() . 'ident_' . $entryIdentifier, $existingTags);
+        }
+    }
+
+    /**
+     * Removes association of the identifier with the given tags
+     *
+     * @param string $entryIdentifier
+     */
+    protected function removeIdentifierFromAllTags($entryIdentifier)
+    {
+        // Get tags for this identifier
+        $tags = $this->findTagsByIdentifier($entryIdentifier);
+        // Deassociate tags with this identifier
+        foreach ($tags as $tag) {
+            $identifiers = $this->findIdentifiersByTag($tag);
+            // Formally array_search() below should never return FALSE due to
+            // the behavior of findTagsByIdentifier(). But if reverse index is
+            // corrupted, we still can get 'FALSE' from array_search(). This is
+            // not a problem because we are removing this identifier from
+            // anywhere.
+            if (($key = array_search($entryIdentifier, $identifiers)) !== false) {
+                unset($identifiers[$key]);
+                if (!empty($identifiers)) {
+                    apc_store($this->getIdentifierPrefix() . 'tag_' . $tag, $identifiers);
+                } else {
+                    apc_delete($this->getIdentifierPrefix() . 'tag_' . $tag);
+                }
+            }
+        }
+        // Clear reverse tag index for this identifier
+        apc_delete($this->getIdentifierPrefix() . 'ident_' . $entryIdentifier);
+    }
+
+    /**
+     * Does nothing, as APC does GC itself
+     */
+    public function collectGarbage()
+    {
+    }
+}

typo3/sysext/core/Classes/Cache/Backend/ApcuBackend.php

@@ -0,0 +1,308 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Backend;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Cache\Exception;
+use TYPO3\CMS\Core\Cache\Exception\InvalidDataException;
+use TYPO3\CMS\Core\Cache\Frontend\FrontendInterface;
+use TYPO3\CMS\Core\Core\Environment;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * A caching backend which stores cache entries by using APCu.
+ *
+ * This backend uses the following types of keys:
+ * - tag_xxx
+ * xxx is tag name, value is array of associated identifiers identifier. This
+ * is "forward" tag index. It is mainly used for obtaining content by tag
+ * (get identifier by tag -> get content by identifier)
+ * - ident_xxx
+ * xxx is identifier, value is array of associated tags. This is "reverse" tag
+ * index. It provides quick access for all tags associated with this identifier
+ * and used when removing the identifier
+ *
+ * Each key is prepended with a prefix. By default prefix consists from two parts
+ * separated by underscore character and ends in yet another underscore character:
+ * - "TYPO3"
+ * - MD5 of path to TYPO3 and user running TYPO3
+ * This prefix makes sure that keys from the different installations do not
+ * conflict.
+ */
+class ApcuBackend extends AbstractBackend implements TaggableBackendInterface
+{
+    /**
+     * A prefix to separate stored data from other data possible stored in the APC
+     *
+     * @var string
+     */
+    protected $identifierPrefix;
+
+    /**
+     * Set the cache identifier prefix.
+     *
+     * @param string $identifierPrefix
+     */
+    protected function setIdentifierPrefix($identifierPrefix)
+    {
+        $this->identifierPrefix = $identifierPrefix;
+    }
+
+    /**
+     * Retrieves the cache identifier prefix.
+     *
+     * @return string
+     */
+    protected function getIdentifierPrefix()
+    {
+        return $this->identifierPrefix;
+    }
+
+    /**
+     * Constructs this backend
+     *
+     * @param string $context Unused, for backward compatibility only
+     * @param array $options Configuration options - unused here
+     * @throws Exception
+     */
+    public function __construct($context, array $options = [])
+    {
+        if (!extension_loaded('apcu')) {
+            throw new Exception('The PHP extension "apcu" must be installed and loaded in order to use the APCu backend.', 1232985914);
+        }
+        if (PHP_SAPI === 'cli' && ini_get('apc.enable_cli') == 0) {
+            throw new Exception('The APCu backend cannot be used because apcu is disabled on CLI.', 1232985915);
+        }
+        parent::__construct($context, $options);
+    }
+
+    /**
+     * Initializes the identifier prefix when setting the cache.
+     *
+     * @param FrontendInterface $cache
+     */
+    public function setCache(FrontendInterface $cache)
+    {
+        parent::setCache($cache);
+        $processUser = $this->getCurrentUserData();
+        $pathHash = GeneralUtility::shortMD5(Environment::getProjectPath() . $processUser['name'] . $this->context . $cache->getIdentifier(), 12);
+        $this->setIdentifierPrefix('TYPO3_' . $pathHash);
+    }
+
+    /**
+     * Returns the current user data with posix_getpwuid or a default structure when
+     * posix_getpwuid is not available.
+     *
+     * @return array
+     */
+    protected function getCurrentUserData()
+    {
+        return extension_loaded('posix') ? posix_getpwuid(posix_geteuid()) : ['name' => 'default'];
+    }
+
+    /**
+     * Saves data in the cache.
+     *
+     * @param string $entryIdentifier An identifier for this specific cache entry
+     * @param string $data The data to be stored
+     * @param array $tags Tags to associate with this cache entry
+     * @param int $lifetime Lifetime of this cache entry in seconds. If NULL is specified, the default lifetime is used. "0" means unlimited lifetime.
+     * @throws Exception if no cache frontend has been set.
+     * @throws InvalidDataException if $data is not a string
+     */
+    public function set($entryIdentifier, $data, array $tags = [], $lifetime = null)
+    {
+        if (!$this->cache instanceof FrontendInterface) {
+            throw new Exception('No cache frontend has been set yet via setCache().', 1232986118);
+        }
+        if (!is_string($data)) {
+            throw new InvalidDataException('The specified data is of type "' . gettype($data) . '" but a string is expected.', 1232986125);
+        }
+        $tags[] = '%APCBE%' . $this->cacheIdentifier;
+        $expiration = $lifetime ?? $this->defaultLifetime;
+        $success = apcu_store($this->getIdentifierPrefix() . $entryIdentifier, $data, $expiration);
+        if ($success === true) {
+            $this->removeIdentifierFromAllTags($entryIdentifier);
+            $this->addIdentifierToTags($entryIdentifier, $tags);
+        } else {
+            $this->logger->alert('Error using APCu: Could not save data in the cache.');
+        }
+    }
+
+    /**
+     * Loads data from the cache.
+     *
+     * @param string $entryIdentifier An identifier which describes the cache entry to load
+     * @return mixed The cache entry's content as a string or FALSE if the cache entry could not be loaded
+     */
+    public function get($entryIdentifier)
+    {
+        $success = false;
+        $value = apcu_fetch($this->getIdentifierPrefix() . $entryIdentifier, $success);
+        return $success ? $value : $success;
+    }
+
+    /**
+     * Checks if a cache entry with the specified identifier exists.
+     *
+     * @param string $entryIdentifier An identifier specifying the cache entry
+     * @return bool TRUE if such an entry exists, FALSE if not
+     */
+    public function has($entryIdentifier)
+    {
+        $success = false;
+        apcu_fetch($this->getIdentifierPrefix() . $entryIdentifier, $success);
+        return $success;
+    }
+
+    /**
+     * Removes all cache entries matching the specified identifier.
+     * Usually this only affects one entry but if - for what reason ever -
+     * old entries for the identifier still exist, they are removed as well.
+     *
+     * @param string $entryIdentifier Specifies the cache entry to remove
+     * @return bool TRUE if (at least) an entry could be removed or FALSE if no entry was found
+     */
+    public function remove($entryIdentifier)
+    {
+        $this->removeIdentifierFromAllTags($entryIdentifier);
+        return apcu_delete($this->getIdentifierPrefix() . $entryIdentifier);
+    }
+
+    /**
+     * Finds and returns all cache entry identifiers which are tagged by the
+     * specified tag.
+     *
+     * @param string $tag The tag to search for
+     * @return array An array with identifiers of all matching entries. An empty array if no entries matched
+     */
+    public function findIdentifiersByTag($tag)
+    {
+        $success = false;
+        $identifiers = apcu_fetch($this->getIdentifierPrefix() . 'tag_' . $tag, $success);
+        if ($success === false) {
+            return [];
+        }
+        return (array)$identifiers;
+    }
+
+    /**
+     * Finds all tags for the given identifier. This function uses reverse tag
+     * index to search for tags.
+     *
+     * @param string $identifier Identifier to find tags by
+     * @return array Array with tags
+     */
+    protected function findTagsByIdentifier($identifier)
+    {
+        $success = false;
+        $tags = apcu_fetch($this->getIdentifierPrefix() . 'ident_' . $identifier, $success);
+        return $success ? (array)$tags : [];
+    }
+
+    /**
+     * Removes all cache entries of this cache.
+     *
+     * @throws Exception
+     */
+    public function flush()
+    {
+        if (!$this->cache instanceof FrontendInterface) {
+            throw new Exception('Yet no cache frontend has been set via setCache().', 1232986571);
+        }
+        $this->flushByTag('%APCBE%' . $this->cacheIdentifier);
+    }
+
+    /**
+     * Removes all cache entries of this cache which are tagged by the specified tag.
+     *
+     * @param string $tag The tag the entries must have
+     */
+    public function flushByTag($tag)
+    {
+        $identifiers = $this->findIdentifiersByTag($tag);
+        foreach ($identifiers as $identifier) {
+            $this->remove($identifier);
+        }
+    }
+
+    /**
+     * Associates the identifier with the given tags
+     *
+     * @param string $entryIdentifier
+     * @param array $tags
+     */
+    protected function addIdentifierToTags($entryIdentifier, array $tags)
+    {
+        // Get identifier-to-tag index to look for updates
+        $existingTags = $this->findTagsByIdentifier($entryIdentifier);
+        $existingTagsUpdated = false;
+
+        foreach ($tags as $tag) {
+            // Update tag-to-identifier index
+            $identifiers = $this->findIdentifiersByTag($tag);
+            if (!in_array($entryIdentifier, $identifiers, true)) {
+                $identifiers[] = $entryIdentifier;
+                apcu_store($this->getIdentifierPrefix() . 'tag_' . $tag, $identifiers);
+            }
+            // Test if identifier-to-tag index needs update
+            if (!in_array($tag, $existingTags, true)) {
+                $existingTags[] = $tag;
+                $existingTagsUpdated = true;
+            }
+        }
+
+        // Update identifier-to-tag index if needed
+        if ($existingTagsUpdated) {
+            apcu_store($this->getIdentifierPrefix() . 'ident_' . $entryIdentifier, $existingTags);
+        }
+    }
+
+    /**
+     * Removes association of the identifier with the given tags
+     *
+     * @param string $entryIdentifier
+     */
+    protected function removeIdentifierFromAllTags($entryIdentifier)
+    {
+        // Get tags for this identifier
+        $tags = $this->findTagsByIdentifier($entryIdentifier);
+        // De-associate tags with this identifier
+        foreach ($tags as $tag) {
+            $identifiers = $this->findIdentifiersByTag($tag);
+            // Formally array_search() below should never return FALSE due to
+            // the behavior of findTagsByIdentifier(). But if reverse index is
+            // corrupted, we still can get 'FALSE' from array_search(). This is
+            // not a problem because we are removing this identifier from
+            // anywhere.
+            if (($key = array_search($entryIdentifier, $identifiers)) !== false) {
+                unset($identifiers[$key]);
+                if (!empty($identifiers)) {
+                    apcu_store($this->getIdentifierPrefix() . 'tag_' . $tag, $identifiers);
+                } else {
+                    apcu_delete($this->getIdentifierPrefix() . 'tag_' . $tag);
+                }
+            }
+        }
+        // Clear reverse tag index for this identifier
+        apcu_delete($this->getIdentifierPrefix() . 'ident_' . $entryIdentifier);
+    }
+
+    /**
+     * Does nothing, as APCu does GC itself
+     */
+    public function collectGarbage()
+    {
+    }
+}

typo3/sysext/core/Classes/Cache/Backend/BackendInterface.php

@@ -0,0 +1,78 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Backend;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Cache;
+
+/**
+ * A contract for a Cache Backend
+ */
+interface BackendInterface
+{
+    /**
+     * Sets a reference to the cache frontend which uses this backend
+     *
+     * @param Cache\Frontend\FrontendInterface $cache The frontend for this backend
+     */
+    public function setCache(Cache\Frontend\FrontendInterface $cache);
+
+    /**
+     * Saves data in the cache.
+     *
+     * @param string $entryIdentifier An identifier for this specific cache entry
+     * @param string $data The data to be stored
+     * @param array $tags Tags to associate with this cache entry. If the backend does not support tags, this option can be ignored.
+     * @param int $lifetime Lifetime of this cache entry in seconds. If NULL is specified, the default lifetime is used. "0" means unlimited lifetime.
+     * @throws \TYPO3\CMS\Core\Cache\Exception if no cache frontend has been set.
+     * @throws \TYPO3\CMS\Core\Cache\Exception\InvalidDataException if the data is not a string
+     */
+    public function set($entryIdentifier, $data, array $tags = [], $lifetime = null);
+
+    /**
+     * Loads data from the cache.
+     *
+     * @param string $entryIdentifier An identifier which describes the cache entry to load
+     * @return mixed The cache entry's content as a string or FALSE if the cache entry could not be loaded
+     */
+    public function get($entryIdentifier);
+
+    /**
+     * Checks if a cache entry with the specified identifier exists.
+     *
+     * @param string $entryIdentifier An identifier specifying the cache entry
+     * @return bool TRUE if such an entry exists, FALSE if not
+     */
+    public function has($entryIdentifier);
+
+    /**
+     * Removes all cache entries matching the specified identifier.
+     * Usually this only affects one entry but if - for what reason ever -
+     * old entries for the identifier still exist, they are removed as well.
+     *
+     * @param string $entryIdentifier Specifies the cache entry to remove
+     * @return bool TRUE if (at least) an entry could be removed or FALSE if no entry was found
+     */
+    public function remove($entryIdentifier);
+
+    /**
+     * Removes all cache entries of this cache.
+     */
+    public function flush();
+
+    /**
+     * Does garbage collection
+     */
+    public function collectGarbage();
+}

typo3/sysext/core/Classes/Cache/Backend/FileBackend.php

@@ -0,0 +1,413 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Backend;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Cache\Exception;
+use TYPO3\CMS\Core\Cache\Exception\InvalidDataException;
+use TYPO3\CMS\Core\Cache\Frontend\FrontendInterface;
+use TYPO3\CMS\Core\Service\OpcodeCacheService;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3\CMS\Core\Utility\PathUtility;
+use TYPO3\CMS\Core\Utility\StringUtility;
+
+/**
+ * A caching backend which stores cache entries in files
+ */
+class FileBackend extends SimpleFileBackend implements FreezableBackendInterface, TaggableBackendInterface
+{
+    const SEPARATOR = '^';
+    const EXPIRYTIME_FORMAT = 'YmdHis';
+    const EXPIRYTIME_LENGTH = 14;
+    const DATASIZE_DIGITS = 10;
+    /**
+     * A file extension to use for each cache entry.
+     *
+     * @var string
+     */
+    protected $cacheEntryFileExtension = '';
+
+    /**
+     * @var array
+     */
+    protected $cacheEntryIdentifiers = [];
+
+    /**
+     * @var bool
+     */
+    protected $frozen = false;
+
+    /**
+     * Freezes this cache backend.
+     *
+     * All data in a frozen backend remains unchanged and methods which try to add
+     * or modify data result in an exception thrown. Possible expiry times of
+     * individual cache entries are ignored.
+     *
+     * On the positive side, a frozen cache backend is much faster on read access.
+     * A frozen backend can only be thawed by calling the flush() method.
+     *
+     * @throws \RuntimeException
+     */
+    public function freeze()
+    {
+        if ($this->frozen === true) {
+            throw new \RuntimeException(sprintf('The cache "%s" is already frozen.', $this->cacheIdentifier), 1323353176);
+        }
+        $cacheEntryFileExtensionLength = strlen($this->cacheEntryFileExtension);
+        for ($directoryIterator = new \DirectoryIterator($this->cacheDirectory); $directoryIterator->valid(); $directoryIterator->next()) {
+            if ($directoryIterator->isDot()) {
+                continue;
+            }
+            if ($cacheEntryFileExtensionLength > 0) {
+                $entryIdentifier = substr($directoryIterator->getFilename(), 0, -$cacheEntryFileExtensionLength);
+            } else {
+                $entryIdentifier = $directoryIterator->getFilename();
+            }
+            $this->cacheEntryIdentifiers[$entryIdentifier] = true;
+            file_put_contents($this->cacheDirectory . $entryIdentifier . $this->cacheEntryFileExtension, $this->get($entryIdentifier));
+        }
+        file_put_contents($this->cacheDirectory . 'FrozenCache.data', serialize($this->cacheEntryIdentifiers));
+        $this->frozen = true;
+    }
+
+    /**
+     * Tells if this backend is frozen.
+     *
+     * @return bool
+     */
+    public function isFrozen()
+    {
+        return $this->frozen;
+    }
+
+    /**
+     * Sets a reference to the cache frontend which uses this backend and
+     * initializes the default cache directory.
+     *
+     * This method also detects if this backend is frozen and sets the internal
+     * flag accordingly.
+     *
+     * @param FrontendInterface $cache The cache frontend
+     */
+    public function setCache(FrontendInterface $cache)
+    {
+        parent::setCache($cache);
+        if (file_exists($this->cacheDirectory . 'FrozenCache.data')) {
+            $this->frozen = true;
+            $this->cacheEntryIdentifiers = unserialize(file_get_contents($this->cacheDirectory . 'FrozenCache.data'));
+        }
+    }
+
+    /**
+     * Saves data in a cache file.
+     *
+     * @param string $entryIdentifier An identifier for this specific cache entry
+     * @param string $data The data to be stored
+     * @param array $tags Tags to associate with this cache entry
+     * @param int $lifetime Lifetime of this cache entry in seconds. If NULL is specified, the default lifetime is used. "0" means unlimited lifetime.
+     * @throws \RuntimeException
+     * @throws InvalidDataException if the directory does not exist or is not writable or exceeds the maximum allowed path length, or if no cache frontend has been set.
+     * @throws Exception if the directory does not exist or is not writable or exceeds the maximum allowed path length, or if no cache frontend has been set.
+     * @throws \InvalidArgumentException
+     */
+    public function set($entryIdentifier, $data, array $tags = [], $lifetime = null)
+    {
+        if (!is_string($data)) {
+            throw new InvalidDataException('The specified data is of type "' . gettype($data) . '" but a string is expected.', 1204481674);
+        }
+        if ($entryIdentifier !== PathUtility::basename($entryIdentifier)) {
+            throw new \InvalidArgumentException('The specified entry identifier must not contain a path segment.', 1282073032);
+        }
+        if ($entryIdentifier === '') {
+            throw new \InvalidArgumentException('The specified entry identifier must not be empty.', 1298114280);
+        }
+        if ($this->frozen === true) {
+            throw new \RuntimeException(sprintf('Cannot add or modify cache entry because the backend of cache "%s" is frozen.', $this->cacheIdentifier), 1323344192);
+        }
+        $this->remove($entryIdentifier);
+        $temporaryCacheEntryPathAndFilename = $this->cacheDirectory . StringUtility::getUniqueId() . '.temp';
+        $lifetime = $lifetime ?? $this->defaultLifetime;
+        $expiryTime = $lifetime === 0 ? 0 : $GLOBALS['EXEC_TIME'] + $lifetime;
+        $metaData = str_pad($expiryTime, self::EXPIRYTIME_LENGTH) . implode(' ', $tags) . str_pad(strlen($data), self::DATASIZE_DIGITS);
+        $result = file_put_contents($temporaryCacheEntryPathAndFilename, $data . $metaData);
+        GeneralUtility::fixPermissions($temporaryCacheEntryPathAndFilename);
+        if ($result === false) {
+            throw new Exception('The temporary cache file "' . $temporaryCacheEntryPathAndFilename . '" could not be written.', 1204026251);
+        }
+        $i = 0;
+        $cacheEntryPathAndFilename = $this->cacheDirectory . $entryIdentifier . $this->cacheEntryFileExtension;
+        while (($result = rename($temporaryCacheEntryPathAndFilename, $cacheEntryPathAndFilename)) === false && $i < 5) {
+            $i++;
+        }
+        if ($result === false) {
+            throw new Exception('The cache file "' . $cacheEntryPathAndFilename . '" could not be written.', 1222361632);
+        }
+        if ($this->cacheEntryFileExtension === '.php') {
+            GeneralUtility::makeInstance(OpcodeCacheService::class)->clearAllActive($cacheEntryPathAndFilename);
+        }
+    }
+
+    /**
+     * Loads data from a cache file.
+     *
+     * @param string $entryIdentifier An identifier which describes the cache entry to load
+     * @return mixed The cache entry's content as a string or FALSE if the cache entry could not be loaded
+     * @throws \InvalidArgumentException If identifier is invalid
+     */
+    public function get($entryIdentifier)
+    {
+        if ($this->frozen === true) {
+            return isset($this->cacheEntryIdentifiers[$entryIdentifier]) ? file_get_contents($this->cacheDirectory . $entryIdentifier . $this->cacheEntryFileExtension) : false;
+        }
+        if ($entryIdentifier !== PathUtility::basename($entryIdentifier)) {
+            throw new \InvalidArgumentException('The specified entry identifier must not contain a path segment.', 1282073033);
+        }
+        $pathAndFilename = $this->cacheDirectory . $entryIdentifier . $this->cacheEntryFileExtension;
+        if ($this->isCacheFileExpired($pathAndFilename)) {
+            return false;
+        }
+        $dataSize = (int)file_get_contents(
+            $pathAndFilename,
+            null,
+            null,
+            filesize($pathAndFilename) - self::DATASIZE_DIGITS,
+            self::DATASIZE_DIGITS
+        );
+        return file_get_contents($pathAndFilename, null, null, 0, $dataSize);
+    }
+
+    /**
+     * Checks if a cache entry with the specified identifier exists.
+     *
+     * @param string $entryIdentifier
+     * @return bool TRUE if such an entry exists, FALSE if not
+     * @throws \InvalidArgumentException
+     */
+    public function has($entryIdentifier)
+    {
+        if ($this->frozen === true) {
+            return isset($this->cacheEntryIdentifiers[$entryIdentifier]);
+        }
+        if ($entryIdentifier !== PathUtility::basename($entryIdentifier)) {
+            throw new \InvalidArgumentException('The specified entry identifier must not contain a path segment.', 1282073034);
+        }
+        return !$this->isCacheFileExpired($this->cacheDirectory . $entryIdentifier . $this->cacheEntryFileExtension);
+    }
+
+    /**
+     * Removes all cache entries matching the specified identifier.
+     * Usually this only affects one entry.
+     *
+     * @param string $entryIdentifier Specifies the cache entry to remove
+     * @return bool TRUE if (at least) an entry could be removed or FALSE if no entry was found
+     * @throws \RuntimeException
+     * @throws \InvalidArgumentException
+     */
+    public function remove($entryIdentifier)
+    {
+        if ($entryIdentifier !== PathUtility::basename($entryIdentifier)) {
+            throw new \InvalidArgumentException('The specified entry identifier must not contain a path segment.', 1282073035);
+        }
+        if ($entryIdentifier === '') {
+            throw new \InvalidArgumentException('The specified entry identifier must not be empty.', 1298114279);
+        }
+        if ($this->frozen === true) {
+            throw new \RuntimeException(sprintf('Cannot remove cache entry because the backend of cache "%s" is frozen.', $this->cacheIdentifier), 1323344193);
+        }
+        $pathAndFilename = $this->cacheDirectory . $entryIdentifier . $this->cacheEntryFileExtension;
+        if (file_exists($pathAndFilename) === false) {
+            return false;
+        }
+        if (@unlink($pathAndFilename) === false) {
+            return false;
+        }
+        return true;
+    }
+
+    /**
+     * Finds and returns all cache entry identifiers which are tagged by the
+     * specified tag.
+     *
+     * @param string $searchedTag The tag to search for
+     * @return array An array with identifiers of all matching entries. An empty array if no entries matched
+     */
+    public function findIdentifiersByTag($searchedTag)
+    {
+        $entryIdentifiers = [];
+        $now = $GLOBALS['EXEC_TIME'];
+        $cacheEntryFileExtensionLength = strlen($this->cacheEntryFileExtension);
+        for ($directoryIterator = GeneralUtility::makeInstance(\DirectoryIterator::class, $this->cacheDirectory); $directoryIterator->valid(); $directoryIterator->next()) {
+            if ($directoryIterator->isDot()) {
+                continue;
+            }
+            $cacheEntryPathAndFilename = $directoryIterator->getPathname();
+            $index = (int)file_get_contents(
+                $cacheEntryPathAndFilename,
+                null,
+                null,
+                filesize($cacheEntryPathAndFilename) - self::DATASIZE_DIGITS,
+                self::DATASIZE_DIGITS
+            );
+            $metaData = file_get_contents($cacheEntryPathAndFilename, null, null, $index);
+            $expiryTime = (int)substr($metaData, 0, self::EXPIRYTIME_LENGTH);
+            if ($expiryTime !== 0 && $expiryTime < $now) {
+                continue;
+            }
+            if (in_array($searchedTag, explode(' ', substr($metaData, self::EXPIRYTIME_LENGTH, -self::DATASIZE_DIGITS)))) {
+                if ($cacheEntryFileExtensionLength > 0) {
+                    $entryIdentifiers[] = substr($directoryIterator->getFilename(), 0, -$cacheEntryFileExtensionLength);
+                } else {
+                    $entryIdentifiers[] = $directoryIterator->getFilename();
+                }
+            }
+        }
+        return $entryIdentifiers;
+    }
+
+    /**
+     * Removes all cache entries of this cache and sets the frozen flag to FALSE.
+     */
+    public function flush()
+    {
+        parent::flush();
+        if ($this->frozen === true) {
+            $this->frozen = false;
+        }
+    }
+
+    /**
+     * Removes all cache entries of this cache which are tagged by the specified tag.
+     *
+     * @param string $tag The tag the entries must have
+     */
+    public function flushByTag($tag)
+    {
+        $identifiers = $this->findIdentifiersByTag($tag);
+        if (empty($identifiers)) {
+            return;
+        }
+        foreach ($identifiers as $entryIdentifier) {
+            $this->remove($entryIdentifier);
+        }
+    }
+
+    /**
+     * Checks if the given cache entry files are still valid or if their
+     * lifetime has exceeded.
+     *
+     * @param string $cacheEntryPathAndFilename
+     * @return bool
+     */
+    protected function isCacheFileExpired($cacheEntryPathAndFilename)
+    {
+        if (file_exists($cacheEntryPathAndFilename) === false) {
+            return true;
+        }
+        $index = (int)file_get_contents(
+            $cacheEntryPathAndFilename,
+            null,
+            null,
+            filesize($cacheEntryPathAndFilename) - self::DATASIZE_DIGITS,
+            self::DATASIZE_DIGITS
+        );
+        $expiryTime = (int)file_get_contents($cacheEntryPathAndFilename, null, null, $index, self::EXPIRYTIME_LENGTH);
+        return $expiryTime !== 0 && $expiryTime < $GLOBALS['EXEC_TIME'];
+    }
+
+    /**
+     * Does garbage collection
+     */
+    public function collectGarbage()
+    {
+        if ($this->frozen === true) {
+            return;
+        }
+        for ($directoryIterator = new \DirectoryIterator($this->cacheDirectory); $directoryIterator->valid(); $directoryIterator->next()) {
+            if ($directoryIterator->isDot()) {
+                continue;
+            }
+            if ($this->isCacheFileExpired($directoryIterator->getPathname())) {
+                $cacheEntryFileExtensionLength = strlen($this->cacheEntryFileExtension);
+                if ($cacheEntryFileExtensionLength > 0) {
+                    $this->remove(substr($directoryIterator->getFilename(), 0, -$cacheEntryFileExtensionLength));
+                } else {
+                    $this->remove($directoryIterator->getFilename());
+                }
+            }
+        }
+    }
+
+    /**
+     * Tries to find the cache entry for the specified identifier.
+     * Usually only one cache entry should be found - if more than one exist, this
+     * is due to some error or crash.
+     *
+     * @param string $entryIdentifier The cache entry identifier
+     * @return mixed The filenames (including path) as an array if one or more entries could be found, otherwise FALSE
+     */
+    protected function findCacheFilesByIdentifier($entryIdentifier)
+    {
+        $pattern = $this->cacheDirectory . $entryIdentifier;
+        $filesFound = glob($pattern);
+        if ($filesFound === false || empty($filesFound)) {
+            return false;
+        }
+        return $filesFound;
+    }
+
+    /**
+     * Loads PHP code from the cache and require_onces it right away.
+     *
+     * @param string $entryIdentifier An identifier which describes the cache entry to load
+     * @throws \InvalidArgumentException
+     * @return mixed Potential return value from the include operation
+     */
+    public function requireOnce($entryIdentifier)
+    {
+        if ($this->frozen === true) {
+            if (isset($this->cacheEntryIdentifiers[$entryIdentifier])) {
+                return require_once $this->cacheDirectory . $entryIdentifier . $this->cacheEntryFileExtension;
+            }
+            return false;
+        }
+        if ($entryIdentifier !== PathUtility::basename($entryIdentifier)) {
+            throw new \InvalidArgumentException('The specified entry identifier must not contain a path segment.', 1282073036);
+        }
+        $pathAndFilename = $this->cacheDirectory . $entryIdentifier . $this->cacheEntryFileExtension;
+        return $this->isCacheFileExpired($pathAndFilename) ? false : require_once $pathAndFilename;
+    }
+
+    /**
+     * Loads PHP code from the cache and require it right away.
+     *
+     * @param string $entryIdentifier An identifier which describes the cache entry to load
+     * @throws \InvalidArgumentException
+     * @return mixed Potential return value from the include operation
+     */
+    public function require(string $entryIdentifier)
+    {
+        if ($this->frozen) {
+            if (isset($this->cacheEntryIdentifiers[$entryIdentifier])) {
+                return require $this->cacheDirectory . $entryIdentifier . $this->cacheEntryFileExtension;
+            }
+            return false;
+        }
+        if ($entryIdentifier !== PathUtility::basename($entryIdentifier)) {
+            throw new \InvalidArgumentException('The specified entry identifier must not contain a path segment.', 1532528246);
+        }
+        $pathAndFilename = $this->cacheDirectory . $entryIdentifier . $this->cacheEntryFileExtension;
+        return $this->isCacheFileExpired($pathAndFilename) ? false : require $pathAndFilename;
+    }
+}

typo3/sysext/core/Classes/Cache/Backend/FreezableBackendInterface.php

@@ -0,0 +1,40 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Backend;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * A contract for a cache backend which can be frozen.
+ */
+interface FreezableBackendInterface extends BackendInterface
+{
+    /**
+     * Freezes this cache backend.
+     *
+     * All data in a frozen backend remains unchanged and methods which try to add
+     * or modify data result in an exception thrown. Possible expiry times of
+     * individual cache entries are ignored.
+     *
+     * On the positive side, a frozen cache backend is much faster on read access.
+     * A frozen backend can only be thawn by calling the flush() method.
+     */
+    public function freeze();
+
+    /**
+     * Tells if this backend is frozen.
+     *
+     * @return bool
+     */
+    public function isFrozen();
+}

typo3/sysext/core/Classes/Cache/Backend/MemcachedBackend.php

@@ -0,0 +1,450 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Backend;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Cache\Exception;
+use TYPO3\CMS\Core\Cache\Frontend\FrontendInterface;
+use TYPO3\CMS\Core\Core\Environment;
+
+/**
+ * A caching backend which stores cache entries by using Memcached.
+ *
+ * This backend uses the following types of Memcache keys:
+ * - tag_xxx
+ * xxx is tag name, value is array of associated identifiers identifier. This
+ * is "forward" tag index. It is mainly used for obtaining content by tag
+ * (get identifier by tag -> get content by identifier)
+ * - ident_xxx
+ * xxx is identifier, value is array of associated tags. This is "reverse" tag
+ * index. It provides quick access for all tags associated with this identifier
+ * and used when removing the identifier
+ *
+ * Each key is prepended with a prefix. By default prefix consists from two parts
+ * separated by underscore character and ends in yet another underscore character:
+ * - "TYPO3"
+ * - Current site path obtained from Environment::getProjectPath()
+ * This prefix makes sure that keys from the different installations do not
+ * conflict.
+ *
+ * Note: When using the Memcached backend to store values of more than ~1 MB,
+ * the data will be split into chunks to make them fit into the memcached limits.
+ */
+class MemcachedBackend extends AbstractBackend implements TaggableBackendInterface, TransientBackendInterface
+{
+    /**
+     * Max bucket size, (1024*1024)-42 bytes
+     *
+     * @var int
+     */
+    const MAX_BUCKET_SIZE = 1048534;
+
+    /**
+     * Instance of the PHP Memcache class
+     *
+     * @var \Memcache|\Memcached
+     */
+    protected $memcache;
+
+    /**
+     * Used PECL module for memcached
+     *
+     * @var string
+     */
+    protected $usedPeclModule = '';
+
+    /**
+     * Array of Memcache server configurations
+     *
+     * @var array
+     */
+    protected $servers = [];
+
+    /**
+     * Indicates whether the memcache uses compression or not (requires zlib),
+     * either 0 or \Memcached::OPT_COMPRESSION / MEMCACHE_COMPRESSED
+     *
+     * @var int
+     */
+    protected $flags;
+
+    /**
+     * A prefix to separate stored data from other data possibly stored in the memcache
+     *
+     * @var string
+     */
+    protected $identifierPrefix;
+
+    /**
+     * Constructs this backend
+     *
+     * @param string $context Unused, for backward compatibility only
+     * @param array $options Configuration options - depends on the actual backend
+     * @throws Exception if memcache is not installed
+     */
+    public function __construct($context, array $options = [])
+    {
+        if (!extension_loaded('memcache') && !extension_loaded('memcached')) {
+            throw new Exception('The PHP extension "memcache" or "memcached" must be installed and loaded in ' . 'order to use the Memcached backend.', 1213987706);
+        }
+
+        parent::__construct($context, $options);
+
+        if ($this->usedPeclModule === '') {
+            if (extension_loaded('memcache')) {
+                $this->usedPeclModule = 'memcache';
+            } elseif (extension_loaded('memcached')) {
+                $this->usedPeclModule = 'memcached';
+            }
+        }
+    }
+
+    /**
+     * Setter for servers to be used. Expects an array,  the values are expected
+     * to be formatted like "<host>[:<port>]" or "unix://<path>"
+     *
+     * @param array $servers An array of servers to add.
+     */
+    protected function setServers(array $servers)
+    {
+        $this->servers = $servers;
+    }
+
+    /**
+     * Setter for compression flags bit
+     *
+     * @param bool $useCompression
+     */
+    protected function setCompression($useCompression)
+    {
+        $compressionFlag = $this->usedPeclModule === 'memcache' ? MEMCACHE_COMPRESSED : \Memcached::OPT_COMPRESSION;
+        if ($useCompression === true) {
+            $this->flags ^= $compressionFlag;
+        } else {
+            $this->flags &= ~$compressionFlag;
+        }
+    }
+
+    /**
+     * Getter for compression flag
+     *
+     * @return bool
+     */
+    protected function getCompression()
+    {
+        return $this->flags !== 0;
+    }
+
+    /**
+     * Initializes the identifier prefix
+     *
+     * @throws Exception
+     */
+    public function initializeObject()
+    {
+        if (empty($this->servers)) {
+            throw new Exception('No servers were given to Memcache', 1213115903);
+        }
+        $memcachedPlugin = '\\' . ucfirst($this->usedPeclModule);
+        $this->memcache = new $memcachedPlugin;
+        $defaultPort = $this->usedPeclModule === 'memcache' ? ini_get('memcache.default_port') : 11211;
+        foreach ($this->servers as $server) {
+            if (strpos($server, 'unix://') === 0) {
+                $host = $server;
+                $port = 0;
+            } else {
+                if (strpos($server, 'tcp://') === 0) {
+                    $server = substr($server, 6);
+                }
+                if (strpos($server, ':') !== false) {
+                    list($host, $port) = explode(':', $server, 2);
+                } else {
+                    $host = $server;
+                    $port = $defaultPort;
+                }
+            }
+            $this->memcache->addserver($host, $port);
+        }
+        if ($this->usedPeclModule === 'memcached') {
+            $this->memcache->setOption(\Memcached::OPT_COMPRESSION, $this->getCompression());
+        }
+    }
+
+    /**
+     * Sets the preferred PECL module
+     *
+     * @param string $peclModule
+     * @throws Exception
+     */
+    public function setPeclModule($peclModule)
+    {
+        if ($peclModule !== 'memcache' && $peclModule !== 'memcached') {
+            throw new Exception('PECL module must be either "memcache" or "memcached".', 1442239768);
+        }
+
+        $this->usedPeclModule = $peclModule;
+    }
+
+    /**
+     * Initializes the identifier prefix when setting the cache.
+     *
+     * @param FrontendInterface $cache The frontend for this backend
+     */
+    public function setCache(FrontendInterface $cache)
+    {
+        parent::setCache($cache);
+        $identifierHash = substr(md5(Environment::getProjectPath() . $this->context . $this->cacheIdentifier), 0, 12);
+        $this->identifierPrefix = 'TYPO3_' . $identifierHash . '_';
+    }
+
+    /**
+     * Saves data in the cache.
+     *
+     * @param string $entryIdentifier An identifier for this specific cache entry
+     * @param string $data The data to be stored
+     * @param array $tags Tags to associate with this cache entry
+     * @param int $lifetime Lifetime of this cache entry in seconds. If NULL is specified, the default lifetime is used. "0" means unlimited lifetime.
+     * @throws Exception if no cache frontend has been set.
+     * @throws \InvalidArgumentException if the identifier is not valid or the final memcached key is longer than 250 characters
+     */
+    public function set($entryIdentifier, $data, array $tags = [], $lifetime = null)
+    {
+        if (strlen($this->identifierPrefix . $entryIdentifier) > 250) {
+            throw new \InvalidArgumentException('Could not set value. Key more than 250 characters (' . $this->identifierPrefix . $entryIdentifier . ').', 1232969508);
+        }
+        if (!$this->cache instanceof FrontendInterface) {
+            throw new Exception('No cache frontend has been set yet via setCache().', 1207149215);
+        }
+        $tags[] = '%MEMCACHEBE%' . $this->cacheIdentifier;
+        $expiration = $lifetime ?? $this->defaultLifetime;
+
+        // Memcached consideres values over 2592000 sec (30 days) as UNIX timestamp
+        // thus $expiration should be converted from lifetime to UNIX timestamp
+        if ($expiration > 2592000) {
+            $expiration += $GLOBALS['EXEC_TIME'];
+        }
+        try {
+            if (is_string($data) && strlen($data) > self::MAX_BUCKET_SIZE) {
+                $data = str_split($data, 1024 * 1000);
+                $success = true;
+                $chunkNumber = 1;
+                foreach ($data as $chunk) {
+                    $success = $success && $this->setInternal($entryIdentifier . '_chunk_' . $chunkNumber, $chunk, $expiration);
+                    $chunkNumber++;
+                }
+                $success = $success && $this->setInternal($entryIdentifier, 'TYPO3*chunked:' . $chunkNumber, $expiration);
+            } else {
+                $success = $this->setInternal($entryIdentifier, $data, $expiration);
+            }
+            if ($success === true) {
+                $this->removeIdentifierFromAllTags($entryIdentifier);
+                $this->addIdentifierToTags($entryIdentifier, $tags);
+            } else {
+                throw new Exception('Could not set data to memcache server.', 1275830266);
+            }
+        } catch (\Exception $exception) {
+            $this->logger->alert('Memcache: could not set value.', ['exception' => $exception]);
+        }
+    }
+
+    /**
+     * Stores the actual data inside memcache/memcached
+     *
+     * @param string $entryIdentifier
+     * @param mixed $data
+     * @param int $expiration
+     * @return bool
+     */
+    protected function setInternal($entryIdentifier, $data, $expiration)
+    {
+        if ($this->usedPeclModule === 'memcache') {
+            return $this->memcache->set($this->identifierPrefix . $entryIdentifier, $data, $this->flags, $expiration);
+        }
+        return $this->memcache->set($this->identifierPrefix . $entryIdentifier, $data, $expiration);
+    }
+
+    /**
+     * Loads data from the cache.
+     *
+     * @param string $entryIdentifier An identifier which describes the cache entry to load
+     * @return mixed The cache entry's content as a string or FALSE if the cache entry could not be loaded
+     */
+    public function get($entryIdentifier)
+    {
+        $value = $this->memcache->get($this->identifierPrefix . $entryIdentifier);
+        if (is_string($value) && strpos($value, 'TYPO3*chunked:') === 0) {
+            list(, $chunkCount) = explode(':', $value);
+            $value = '';
+            for ($chunkNumber = 1; $chunkNumber < $chunkCount; $chunkNumber++) {
+                $value .= $this->memcache->get($this->identifierPrefix . $entryIdentifier . '_chunk_' . $chunkNumber);
+            }
+        }
+        return $value;
+    }
+
+    /**
+     * Checks if a cache entry with the specified identifier exists.
+     *
+     * @param string $entryIdentifier An identifier specifying the cache entry
+     * @return bool TRUE if such an entry exists, FALSE if not
+     */
+    public function has($entryIdentifier)
+    {
+        if ($this->usedPeclModule === 'memcache') {
+            return $this->memcache->get($this->identifierPrefix . $entryIdentifier) !== false;
+        }
+
+        // pecl-memcached supports storing literal FALSE
+        $this->memcache->get($this->identifierPrefix . $entryIdentifier);
+        return $this->memcache->getResultCode() !== \Memcached::RES_NOTFOUND;
+    }
+
+    /**
+     * Removes all cache entries matching the specified identifier.
+     * Usually this only affects one entry but if - for what reason ever -
+     * old entries for the identifier still exist, they are removed as well.
+     *
+     * @param string $entryIdentifier Specifies the cache entry to remove
+     * @return bool TRUE if (at least) an entry could be removed or FALSE if no entry was found
+     */
+    public function remove($entryIdentifier)
+    {
+        $this->removeIdentifierFromAllTags($entryIdentifier);
+        return $this->memcache->delete($this->identifierPrefix . $entryIdentifier, 0);
+    }
+
+    /**
+     * Finds and returns all cache entry identifiers which are tagged by the
+     * specified tag.
+     *
+     * @param string $tag The tag to search for
+     * @return array An array of entries with all matching entries. An empty array if no entries matched
+     */
+    public function findIdentifiersByTag($tag)
+    {
+        $identifiers = $this->memcache->get($this->identifierPrefix . 'tag_' . $tag);
+        if ($identifiers !== false) {
+            return (array)$identifiers;
+        }
+        return [];
+    }
+
+    /**
+     * Removes all cache entries of this cache.
+     *
+     * @throws Exception
+     */
+    public function flush()
+    {
+        if (!$this->cache instanceof FrontendInterface) {
+            throw new Exception('No cache frontend has been set via setCache() yet.', 1204111376);
+        }
+        $this->flushByTag('%MEMCACHEBE%' . $this->cacheIdentifier);
+    }
+
+    /**
+     * Removes all cache entries of this cache which are tagged by the specified tag.
+     *
+     * @param string $tag The tag the entries must have
+     */
+    public function flushByTag($tag)
+    {
+        $identifiers = $this->findIdentifiersByTag($tag);
+        foreach ($identifiers as $identifier) {
+            $this->remove($identifier);
+        }
+    }
+
+    /**
+     * Associates the identifier with the given tags
+     *
+     * @param string $entryIdentifier
+     * @param array $tags
+     */
+    protected function addIdentifierToTags($entryIdentifier, array $tags)
+    {
+        // Get identifier-to-tag index to look for updates
+        $existingTags = $this->findTagsByIdentifier($entryIdentifier);
+        $existingTagsUpdated = false;
+
+        foreach ($tags as $tag) {
+            // Update tag-to-identifier index
+            $identifiers = $this->findIdentifiersByTag($tag);
+            if (!in_array($entryIdentifier, $identifiers, true)) {
+                $identifiers[] = $entryIdentifier;
+                $this->memcache->set($this->identifierPrefix . 'tag_' . $tag, $identifiers);
+            }
+            // Test if identifier-to-tag index needs update
+            if (!in_array($tag, $existingTags, true)) {
+                $existingTags[] = $tag;
+                $existingTagsUpdated = true;
+            }
+        }
+
+        // Update identifier-to-tag index if needed
+        if ($existingTagsUpdated) {
+            $this->memcache->set($this->identifierPrefix . 'ident_' . $entryIdentifier, $existingTags);
+        }
+    }
+
+    /**
+     * Removes association of the identifier with the given tags
+     *
+     * @param string $entryIdentifier
+     */
+    protected function removeIdentifierFromAllTags($entryIdentifier)
+    {
+        // Get tags for this identifier
+        $tags = $this->findTagsByIdentifier($entryIdentifier);
+        // De-associate tags with this identifier
+        foreach ($tags as $tag) {
+            $identifiers = $this->findIdentifiersByTag($tag);
+            // Formally array_search() below should never return FALSE due to
+            // the behavior of findTagsByIdentifier(). But if reverse index is
+            // corrupted, we still can get 'FALSE' from array_search(). This is
+            // not a problem because we are removing this identifier from
+            // anywhere.
+            if (($key = array_search($entryIdentifier, $identifiers)) !== false) {
+                unset($identifiers[$key]);
+                if (!empty($identifiers)) {
+                    $this->memcache->set($this->identifierPrefix . 'tag_' . $tag, $identifiers);
+                } else {
+                    $this->memcache->delete($this->identifierPrefix . 'tag_' . $tag, 0);
+                }
+            }
+        }
+        // Clear reverse tag index for this identifier
+        $this->memcache->delete($this->identifierPrefix . 'ident_' . $entryIdentifier, 0);
+    }
+
+    /**
+     * Finds all tags for the given identifier. This function uses reverse tag
+     * index to search for tags.
+     *
+     * @param string $identifier Identifier to find tags by
+     * @return array
+     */
+    protected function findTagsByIdentifier($identifier)
+    {
+        $tags = $this->memcache->get($this->identifierPrefix . 'ident_' . $identifier);
+        return $tags === false ? [] : (array)$tags;
+    }
+
+    /**
+     * Does nothing, as memcached does GC itself
+     */
+    public function collectGarbage()
+    {
+    }
+}

typo3/sysext/core/Classes/Cache/Backend/NullBackend.php

@@ -0,0 +1,127 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Backend;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * A caching backend which forgets everything immediately
+ */
+class NullBackend extends AbstractBackend implements PhpCapableBackendInterface, TaggableBackendInterface
+{
+    /**
+     * Acts as if it would save data
+     *
+     * @param string $entryIdentifier ignored
+     * @param string $data ignored
+     * @param array $tags ignored
+     * @param int $lifetime ignored
+     */
+    public function set($entryIdentifier, $data, array $tags = [], $lifetime = null)
+    {
+    }
+
+    /**
+     * Acts as if it would enable data compression
+     *
+     * @param bool $compression ignored
+     */
+    public function setCompression($compression)
+    {
+    }
+
+    /**
+     * Returns False
+     *
+     * @param string $entryIdentifier ignored
+     * @return bool FALSE
+     */
+    public function get($entryIdentifier)
+    {
+        return false;
+    }
+
+    /**
+     * Returns False
+     *
+     * @param string $entryIdentifier ignored
+     * @return bool FALSE
+     */
+    public function has($entryIdentifier)
+    {
+        return false;
+    }
+
+    /**
+     * Does nothing
+     *
+     * @param string $entryIdentifier ignored
+     * @return bool FALSE
+     */
+    public function remove($entryIdentifier)
+    {
+        return false;
+    }
+
+    /**
+     * Returns an empty array
+     *
+     * @param string $tag ignored
+     * @return array An empty array
+     */
+    public function findIdentifiersByTag($tag)
+    {
+        return [];
+    }
+
+    /**
+     * Does nothing
+     */
+    public function flush()
+    {
+    }
+
+    /**
+     * Does nothing
+     *
+     * @param string $tag ignored
+     */
+    public function flushByTag($tag)
+    {
+    }
+
+    /**
+     * Does nothing
+     */
+    public function collectGarbage()
+    {
+    }
+
+    /**
+     * Does nothing
+     *
+     * @param string $identifier An identifier which describes the cache entry to load
+     */
+    public function requireOnce($identifier)
+    {
+    }
+
+    /**
+     * Does nothing
+     *
+     * @param string $identifier An identifier which describes the cache entry to load
+     */
+    public function require(string $identifier)
+    {
+    }
+}

typo3/sysext/core/Classes/Cache/Backend/PdoBackend.php

@@ -0,0 +1,299 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Backend;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Cache\Exception;
+use TYPO3\CMS\Core\Cache\Exception\InvalidDataException;
+use TYPO3\CMS\Core\Cache\Frontend\FrontendInterface;
+use TYPO3\CMS\Core\Utility\ExtensionManagementUtility;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * A PDO database cache backend
+ */
+class PdoBackend extends AbstractBackend implements TaggableBackendInterface
+{
+    /**
+     * @var string
+     */
+    protected $dataSourceName;
+
+    /**
+     * @var string
+     */
+    protected $username;
+
+    /**
+     * @var string
+     */
+    protected $password;
+
+    /**
+     * @var \PDO
+     */
+    protected $databaseHandle;
+
+    /**
+     * @var string
+     */
+    protected $pdoDriver;
+
+    /**
+     * Sets the DSN to use
+     *
+     * @param string $DSN The DSN to use for connecting to the DB
+     */
+    public function setDataSourceName($DSN)
+    {
+        $this->dataSourceName = $DSN;
+    }
+
+    /**
+     * Sets the username to use
+     *
+     * @param string $username The username to use for connecting to the DB
+     */
+    public function setUsername($username)
+    {
+        $this->username = $username;
+    }
+
+    /**
+     * Sets the password to use
+     *
+     * @param string $password The password to use for connecting to the DB
+     */
+    public function setPassword($password)
+    {
+        $this->password = $password;
+    }
+
+    /**
+     * Initialize the cache backend.
+     */
+    public function initializeObject()
+    {
+        $this->connect();
+    }
+
+    /**
+     * Saves data in the cache.
+     *
+     * @param string $entryIdentifier An identifier for this specific cache entry
+     * @param string $data The data to be stored
+     * @param array $tags Tags to associate with this cache entry
+     * @param int $lifetime Lifetime of this cache entry in seconds. If NULL is specified, the default lifetime is used. "0" means unlimited lifetime.
+     * @throws Exception if no cache frontend has been set.
+     * @throws \InvalidArgumentException if the identifier is not valid
+     * @throws InvalidDataException if $data is not a string
+     */
+    public function set($entryIdentifier, $data, array $tags = [], $lifetime = null)
+    {
+        if (!$this->cache instanceof FrontendInterface) {
+            throw new Exception('No cache frontend has been set yet via setCache().', 1259515600);
+        }
+        if (!is_string($data)) {
+            throw new InvalidDataException('The specified data is of type "' . gettype($data) . '" but a string is expected.', 1259515601);
+        }
+        $this->remove($entryIdentifier);
+        $lifetime = $lifetime ?? $this->defaultLifetime;
+        $statementHandle = $this->databaseHandle->prepare('INSERT INTO "cache" ("identifier", "context", "cache", "created", "lifetime", "content") VALUES (?, ?, ?, ?, ?, ?)');
+        $result = $statementHandle->execute([$entryIdentifier, $this->context, $this->cacheIdentifier, $GLOBALS['EXEC_TIME'], $lifetime, $data]);
+        if ($result === false) {
+            throw new Exception('The cache entry "' . $entryIdentifier . '" could not be written.', 1259530791);
+        }
+        $statementHandle = $this->databaseHandle->prepare('INSERT INTO "tags" ("identifier", "context", "cache", "tag") VALUES (?, ?, ?, ?)');
+        foreach ($tags as $tag) {
+            $result = $statementHandle->execute([$entryIdentifier, $this->context, $this->cacheIdentifier, $tag]);
+            if ($result === false) {
+                throw new Exception('The tag "' . $tag . ' for cache entry "' . $entryIdentifier . '" could not be written.', 1259530751);
+            }
+        }
+    }
+
+    /**
+     * Loads data from the cache.
+     *
+     * @param string $entryIdentifier An identifier which describes the cache entry to load
+     * @return mixed The cache entry's content as a string or FALSE if the cache entry could not be loaded
+     */
+    public function get($entryIdentifier)
+    {
+        $statementHandle = $this->databaseHandle->prepare('SELECT "content" FROM "cache" WHERE "identifier"=? AND "context"=? AND "cache"=?' . $this->getNotExpiredStatement());
+        $statementHandle->execute([$entryIdentifier, $this->context, $this->cacheIdentifier]);
+        return $statementHandle->fetchColumn();
+    }
+
+    /**
+     * Checks if a cache entry with the specified identifier exists.
+     *
+     * @param string $entryIdentifier An identifier specifying the cache entry
+     * @return bool TRUE if such an entry exists, FALSE if not
+     */
+    public function has($entryIdentifier)
+    {
+        $statementHandle = $this->databaseHandle->prepare('SELECT COUNT("identifier") FROM "cache" WHERE "identifier"=? AND "context"=? AND "cache"=?' . $this->getNotExpiredStatement());
+        $statementHandle->execute([$entryIdentifier, $this->context, $this->cacheIdentifier]);
+        return $statementHandle->fetchColumn() > 0;
+    }
+
+    /**
+     * Removes all cache entries matching the specified identifier.
+     * Usually this only affects one entry but if - for what reason ever -
+     * old entries for the identifier still exist, they are removed as well.
+     *
+     * @param string $entryIdentifier Specifies the cache entry to remove
+     * @return bool TRUE if (at least) an entry could be removed or FALSE if no entry was found
+     */
+    public function remove($entryIdentifier)
+    {
+        $statementHandle = $this->databaseHandle->prepare('DELETE FROM "tags" WHERE "identifier"=? AND "context"=? AND "cache"=?');
+        $statementHandle->execute([$entryIdentifier, $this->context, $this->cacheIdentifier]);
+        $statementHandle = $this->databaseHandle->prepare('DELETE FROM "cache" WHERE "identifier"=? AND "context"=? AND "cache"=?');
+        $statementHandle->execute([$entryIdentifier, $this->context, $this->cacheIdentifier]);
+        return $statementHandle->rowCount() > 0;
+    }
+
+    /**
+     * Removes all cache entries of this cache.
+     */
+    public function flush()
+    {
+        $statementHandle = $this->databaseHandle->prepare('DELETE FROM "tags" WHERE "context"=? AND "cache"=?');
+        $statementHandle->execute([$this->context, $this->cacheIdentifier]);
+        $statementHandle = $this->databaseHandle->prepare('DELETE FROM "cache" WHERE "context"=? AND "cache"=?');
+        $statementHandle->execute([$this->context, $this->cacheIdentifier]);
+    }
+
+    /**
+     * Removes all cache entries of this cache which are tagged by the specified tag.
+     *
+     * @param string $tag The tag the entries must have
+     */
+    public function flushByTag($tag)
+    {
+        $statementHandle = $this->databaseHandle->prepare('DELETE FROM "cache" WHERE "context"=? AND "cache"=? AND "identifier" IN (SELECT "identifier" FROM "tags" WHERE "context"=? AND "cache"=? AND "tag"=?)');
+        $statementHandle->execute([$this->context, $this->cacheIdentifier, $this->context, $this->cacheIdentifier, $tag]);
+        $statementHandle = $this->databaseHandle->prepare('DELETE FROM "tags" WHERE "context"=? AND "cache"=? AND "tag"=?');
+        $statementHandle->execute([$this->context, $this->cacheIdentifier, $tag]);
+    }
+
+    /**
+     * Finds and returns all cache entry identifiers which are tagged by the
+     * specified tag.
+     *
+     * @param string $tag The tag to search for
+     * @return array An array with identifiers of all matching entries. An empty array if no entries matched
+     */
+    public function findIdentifiersByTag($tag)
+    {
+        $statementHandle = $this->databaseHandle->prepare('SELECT "identifier" FROM "tags" WHERE "context"=?  AND "cache"=? AND "tag"=?');
+        $statementHandle->execute([$this->context, $this->cacheIdentifier, $tag]);
+        return $statementHandle->fetchAll(\PDO::FETCH_COLUMN);
+    }
+
+    /**
+     * Does garbage collection
+     */
+    public function collectGarbage()
+    {
+        $statementHandle = $this->databaseHandle->prepare('DELETE FROM "tags" WHERE "context"=? AND "cache"=? AND "identifier" IN ' . '(SELECT "identifier" FROM "cache" WHERE "context"=? AND "cache"=? AND "lifetime" > 0 AND "created" + "lifetime" < ' . $GLOBALS['EXEC_TIME'] . ')');
+        $statementHandle->execute([$this->context, $this->cacheIdentifier, $this->context, $this->cacheIdentifier]);
+        $statementHandle = $this->databaseHandle->prepare('DELETE FROM "cache" WHERE "context"=? AND "cache"=? AND "lifetime" > 0 AND "created" + "lifetime" < ' . $GLOBALS['EXEC_TIME']);
+        $statementHandle->execute([$this->context, $this->cacheIdentifier]);
+    }
+
+    /**
+     * Returns an SQL statement that evaluates to TRUE if the entry is not expired.
+     *
+     * @return string
+     */
+    protected function getNotExpiredStatement()
+    {
+        return ' AND ("lifetime" = 0 OR "created" + "lifetime" >= ' . $GLOBALS['EXEC_TIME'] . ')';
+    }
+
+    /**
+     * Connect to the database
+     *
+     * @throws \RuntimeException if something goes wrong
+     */
+    protected function connect()
+    {
+        try {
+            $splitdsn = explode(':', $this->dataSourceName, 2);
+            $this->pdoDriver = $splitdsn[0];
+            if ($this->pdoDriver === 'sqlite' && !file_exists($splitdsn[1])) {
+                $this->databaseHandle = GeneralUtility::makeInstance(\PDO::class, $this->dataSourceName, $this->username, $this->password);
+                $this->createCacheTables();
+            } else {
+                $this->databaseHandle = GeneralUtility::makeInstance(\PDO::class, $this->dataSourceName, $this->username, $this->password);
+            }
+            $this->databaseHandle->setAttribute(\PDO::ATTR_ERRMODE, \PDO::ERRMODE_EXCEPTION);
+            if (strpos($this->pdoDriver, 'mysql') === 0) {
+                $this->databaseHandle->exec('SET SESSION sql_mode=\'ANSI\';');
+            }
+        } catch (\PDOException $e) {
+            throw new \RuntimeException('Could not connect to cache table with DSN "' . $this->dataSourceName . '". PDO error: ' . $e->getMessage(), 1334736164);
+        }
+    }
+
+    /**
+     * Creates the tables needed for the cache backend.
+     *
+     * @throws \RuntimeException if something goes wrong
+     */
+    protected function createCacheTables()
+    {
+        try {
+            $this->importSql(
+                $this->databaseHandle,
+                $this->pdoDriver,
+                ExtensionManagementUtility::extPath('core') .
+                'Resources/Private/Sql/Cache/Backend/PdoBackendCacheAndTags.sql'
+            );
+        } catch (\PDOException $e) {
+            throw new \RuntimeException('Could not create cache tables with DSN "' . $this->dataSourceName . '". PDO error: ' . $e->getMessage(), 1259576985);
+        }
+    }
+
+    /**
+     * Pumps the SQL into the database. Use for DDL only.
+     *
+     * Important: key definitions with length specifiers (needed for MySQL) must
+     * be given as "field"(xyz) - no space between double quote and parenthesis -
+     * so they can be removed automatically.
+     *
+     * @param \PDO $databaseHandle
+     * @param string $pdoDriver
+     * @param string $pathAndFilename
+     */
+    protected function importSql(\PDO $databaseHandle, string $pdoDriver, string $pathAndFilename): void
+    {
+        $sql = file($pathAndFilename, FILE_IGNORE_NEW_LINES & FILE_SKIP_EMPTY_LINES);
+        // Remove MySQL style key length delimiters (yuck!) if we are not setting up a MySQL db
+        if (strpos($pdoDriver, 'mysql') !== 0) {
+            $sql = preg_replace('/"\\([0-9]+\\)/', '"', $sql);
+        }
+        $statement = '';
+        foreach ($sql as $line) {
+            $statement .= ' ' . trim($line);
+            if (substr($statement, -1) === ';') {
+                $databaseHandle->exec($statement);
+                $statement = '';
+            }
+        }
+    }
+}

typo3/sysext/core/Classes/Cache/Backend/PhpCapableBackendInterface.php

@@ -0,0 +1,32 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Backend;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * A contract for a cache backend which is capable of storing, retrieving and
+ * including PHP source code.
+ */
+interface PhpCapableBackendInterface extends BackendInterface
+{
+    /**
+     * Loads PHP code from the cache and require_onces it right away.
+     *
+     * @param string $entryIdentifier An identifier which describes the cache entry to load
+     * @return mixed Potential return value from the include operation
+     */
+    public function requireOnce($entryIdentifier);
+
+    // @todo: Add require() as breaking patch in TYPO3 v10.0 to the interface
+}

typo3/sysext/core/Classes/Cache/Backend/RedisBackend.php

@@ -0,0 +1,554 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Backend;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Cache\Exception;
+use TYPO3\CMS\Core\Cache\Exception\InvalidDataException;
+use TYPO3\CMS\Core\Utility\StringUtility;
+
+/**
+ * A caching backend which stores cache entries by using Redis with phpredis
+ * PHP module. Redis is a noSQL database with very good scaling characteristics
+ * in proportion to the amount of entries and data size.
+ *
+ * @see https://redis.io/
+ * @see https://github.com/phpredis/phpredis
+ */
+class RedisBackend extends AbstractBackend implements TaggableBackendInterface
+{
+    /**
+     * Faked unlimited lifetime = 31536000 (1 Year).
+     * In redis an entry does not have a lifetime by default (it's not "volatile").
+     * Entries can be made volatile either with EXPIRE after it has been SET,
+     * or with SETEX, which is a combined SET and EXPIRE command.
+     * But an entry can not be made "unvolatile" again. To set a volatile entry to
+     * not volatile again, it must be DELeted and SET without a following EXPIRE.
+     * To save these additional calls on every set(),
+     * we just make every entry volatile and treat a high number as "unlimited"
+     *
+     * @see https://redis.io/commands/expire
+     * @var int Faked unlimited lifetime
+     */
+    const FAKED_UNLIMITED_LIFETIME = 31536000;
+    /**
+     * Key prefix for identifier->data entries
+     *
+     * @var string
+     */
+    const IDENTIFIER_DATA_PREFIX = 'identData:';
+    /**
+     * Key prefix for identifier->tags sets
+     *
+     * @var string
+     */
+    const IDENTIFIER_TAGS_PREFIX = 'identTags:';
+    /**
+     * Key prefix for tag->identifiers sets
+     *
+     * @var string
+     */
+    const TAG_IDENTIFIERS_PREFIX = 'tagIdents:';
+    /**
+     * Instance of the PHP redis class
+     *
+     * @var \Redis
+     */
+    protected $redis;
+
+    /**
+     * Indicates whether the server is connected
+     *
+     * @var bool
+     */
+    protected $connected = false;
+
+    /**
+     * Persistent connection
+     *
+     * @var bool
+     */
+    protected $persistentConnection = false;
+
+    /**
+     * Hostname / IP of the Redis server, defaults to 127.0.0.1.
+     *
+     * @var string
+     */
+    protected $hostname = '127.0.0.1';
+
+    /**
+     * Port of the Redis server, defaults to 6379
+     *
+     * @var int
+     */
+    protected $port = 6379;
+
+    /**
+     * Number of selected database, defaults to 0
+     *
+     * @var int
+     */
+    protected $database = 0;
+
+    /**
+     * Password for redis authentication
+     *
+     * @var string
+     */
+    protected $password = '';
+
+    /**
+     * Indicates whether data is compressed or not (requires php zlib)
+     *
+     * @var bool
+     */
+    protected $compression = false;
+
+    /**
+     * -1 to 9, indicates zlib compression level: -1 = default level 6, 0 = no compression, 9 maximum compression
+     *
+     * @var int
+     */
+    protected $compressionLevel = -1;
+
+    /**
+     * limit in seconds (default is 0 meaning unlimited)
+     *
+     * @var int
+     */
+    protected $connectionTimeout = 0;
+
+    /**
+     * Construct this backend
+     *
+     * @param string $context Unused, for backward compatibility only
+     * @param array $options Configuration options
+     * @throws Exception if php redis module is not loaded
+     */
+    public function __construct($context, array $options = [])
+    {
+        if (!extension_loaded('redis')) {
+            throw new Exception('The PHP extension "redis" must be installed and loaded in order to use the redis backend.', 1279462933);
+        }
+        parent::__construct($context, $options);
+    }
+
+    /**
+     * Initializes the redis backend
+     *
+     * @throws Exception if access to redis with password is denied or if database selection fails
+     */
+    public function initializeObject()
+    {
+        $this->redis = new \Redis();
+        try {
+            if ($this->persistentConnection) {
+                $this->connected = $this->redis->pconnect($this->hostname, $this->port, $this->connectionTimeout, (string)$this->database);
+            } else {
+                $this->connected = $this->redis->connect($this->hostname, $this->port, $this->connectionTimeout);
+            }
+        } catch (\Exception $e) {
+            $this->logger->alert('Could not connect to redis server.', ['exception' => $e]);
+        }
+        if ($this->connected) {
+            if ($this->password !== '') {
+                $success = $this->redis->auth($this->password);
+                if (!$success) {
+                    throw new Exception('The given password was not accepted by the redis server.', 1279765134);
+                }
+            }
+            if ($this->database >= 0) {
+                $success = $this->redis->select($this->database);
+                if (!$success) {
+                    throw new Exception('The given database "' . $this->database . '" could not be selected.', 1279765144);
+                }
+            }
+        }
+    }
+
+    /**
+     * Setter for persistent connection
+     *
+     * @param bool $persistentConnection
+     */
+    public function setPersistentConnection($persistentConnection)
+    {
+        $this->persistentConnection = $persistentConnection;
+    }
+
+    /**
+     * Setter for server hostname
+     *
+     * @param string $hostname Hostname
+     */
+    public function setHostname($hostname)
+    {
+        $this->hostname = $hostname;
+    }
+
+    /**
+     * Setter for server port
+     *
+     * @param int $port Port
+     */
+    public function setPort($port)
+    {
+        $this->port = $port;
+    }
+
+    /**
+     * Setter for database number
+     *
+     * @param int $database Database
+     * @throws \InvalidArgumentException if database number is not valid
+     */
+    public function setDatabase($database)
+    {
+        if (!is_int($database)) {
+            throw new \InvalidArgumentException('The specified database number is of type "' . gettype($database) . '" but an integer is expected.', 1279763057);
+        }
+        if ($database < 0) {
+            throw new \InvalidArgumentException('The specified database "' . $database . '" must be greater or equal than zero.', 1279763534);
+        }
+        $this->database = $database;
+    }
+
+    /**
+     * Setter for authentication password
+     *
+     * @param string $password Password
+     */
+    public function setPassword($password)
+    {
+        $this->password = $password;
+    }
+
+    /**
+     * Enable data compression
+     *
+     * @param bool $compression TRUE to enable compression
+     * @throws \InvalidArgumentException if compression parameter is not of type boolean
+     */
+    public function setCompression($compression)
+    {
+        if (!is_bool($compression)) {
+            throw new \InvalidArgumentException('The specified compression of type "' . gettype($compression) . '" but a boolean is expected.', 1289679153);
+        }
+        $this->compression = $compression;
+    }
+
+    /**
+     * Set data compression level.
+     * If compression is enabled and this is not set,
+     * gzcompress default level will be used.
+     *
+     * @param int $compressionLevel -1 to 9: Compression level
+     * @throws \InvalidArgumentException if compressionLevel parameter is not within allowed bounds
+     */
+    public function setCompressionLevel($compressionLevel)
+    {
+        if (!is_int($compressionLevel)) {
+            throw new \InvalidArgumentException('The specified compression of type "' . gettype($compressionLevel) . '" but an integer is expected.', 1289679154);
+        }
+        if ($compressionLevel >= -1 && $compressionLevel <= 9) {
+            $this->compressionLevel = $compressionLevel;
+        } else {
+            throw new \InvalidArgumentException('The specified compression level must be an integer between -1 and 9.', 1289679155);
+        }
+    }
+
+    /**
+     * Set connection timeout.
+     * This value in seconds is used as a maximum number
+     * of seconds to wait if a connection can be established.
+     *
+     * @param int $connectionTimeout limit in seconds, a value greater or equal than 0
+     * @throws \InvalidArgumentException if compressionLevel parameter is not within allowed bounds
+     */
+    public function setConnectionTimeout($connectionTimeout)
+    {
+        if (!is_int($connectionTimeout)) {
+            throw new \InvalidArgumentException('The specified connection timeout is of type "' . gettype($connectionTimeout) . '" but an integer is expected.', 1487849315);
+        }
+
+        if ($connectionTimeout < 0) {
+            throw new \InvalidArgumentException('The specified connection timeout "' . $connectionTimeout . '" must be greater or equal than zero.', 1487849326);
+        }
+
+        $this->connectionTimeout = $connectionTimeout;
+    }
+
+    /**
+     * Save data in the cache
+     *
+     * Scales O(1) with number of cache entries
+     * Scales O(n) with number of tags
+     *
+     * @param string $entryIdentifier Identifier for this specific cache entry
+     * @param string $data Data to be stored
+     * @param array $tags Tags to associate with this cache entry
+     * @param int $lifetime Lifetime of this cache entry in seconds. If NULL is specified, default lifetime is used. "0" means unlimited lifetime.
+     * @throws \InvalidArgumentException if identifier is not valid
+     * @throws InvalidDataException if data is not a string
+     */
+    public function set($entryIdentifier, $data, array $tags = [], $lifetime = null)
+    {
+        if (!$this->canBeUsedInStringContext($entryIdentifier)) {
+            throw new \InvalidArgumentException('The specified identifier is of type "' . gettype($entryIdentifier) . '" which can\'t be converted to string.', 1377006651);
+        }
+        if (!is_string($data)) {
+            throw new InvalidDataException('The specified data is of type "' . gettype($data) . '" but a string is expected.', 1279469941);
+        }
+        $lifetime = $lifetime ?? $this->defaultLifetime;
+        if (!is_int($lifetime)) {
+            throw new \InvalidArgumentException('The specified lifetime is of type "' . gettype($lifetime) . '" but an integer or NULL is expected.', 1279488008);
+        }
+        if ($lifetime < 0) {
+            throw new \InvalidArgumentException('The specified lifetime "' . $lifetime . '" must be greater or equal than zero.', 1279487573);
+        }
+        if ($this->connected) {
+            $expiration = $lifetime === 0 ? self::FAKED_UNLIMITED_LIFETIME : $lifetime;
+            if ($this->compression) {
+                $data = gzcompress($data, $this->compressionLevel);
+            }
+            $this->redis->setex(self::IDENTIFIER_DATA_PREFIX . $entryIdentifier, $expiration, $data);
+            $addTags = $tags;
+            $removeTags = [];
+            $existingTags = $this->redis->sMembers(self::IDENTIFIER_TAGS_PREFIX . $entryIdentifier);
+            if (!empty($existingTags)) {
+                $addTags = array_diff($tags, $existingTags);
+                $removeTags = array_diff($existingTags, $tags);
+            }
+            if (!empty($removeTags) || !empty($addTags)) {
+                $queue = $this->redis->multi(\Redis::PIPELINE);
+                foreach ($removeTags as $tag) {
+                    $queue->sRem(self::IDENTIFIER_TAGS_PREFIX . $entryIdentifier, $tag);
+                    $queue->sRem(self::TAG_IDENTIFIERS_PREFIX . $tag, $entryIdentifier);
+                }
+                foreach ($addTags as $tag) {
+                    $queue->sAdd(self::IDENTIFIER_TAGS_PREFIX . $entryIdentifier, $tag);
+                    $queue->sAdd(self::TAG_IDENTIFIERS_PREFIX . $tag, $entryIdentifier);
+                }
+                $queue->exec();
+            }
+        }
+    }
+
+    /**
+     * Loads data from the cache.
+     *
+     * Scales O(1) with number of cache entries
+     *
+     * @param string $entryIdentifier An identifier which describes the cache entry to load
+     * @return mixed The cache entry's content as a string or FALSE if the cache entry could not be loaded
+     * @throws \InvalidArgumentException if identifier is not a string
+     */
+    public function get($entryIdentifier)
+    {
+        if (!$this->canBeUsedInStringContext($entryIdentifier)) {
+            throw new \InvalidArgumentException('The specified identifier is of type "' . gettype($entryIdentifier) . '" which can\'t be converted to string.', 1377006652);
+        }
+        $storedEntry = false;
+        if ($this->connected) {
+            $storedEntry = $this->redis->get(self::IDENTIFIER_DATA_PREFIX . $entryIdentifier);
+        }
+        if ($this->compression && (string)$storedEntry !== '') {
+            $storedEntry = gzuncompress($storedEntry);
+        }
+        return $storedEntry;
+    }
+
+    /**
+     * Checks if a cache entry with the specified identifier exists.
+     *
+     * Scales O(1) with number of cache entries
+     *
+     * @param string $entryIdentifier Identifier specifying the cache entry
+     * @return bool TRUE if such an entry exists, FALSE if not
+     * @throws \InvalidArgumentException if identifier is not a string
+     */
+    public function has($entryIdentifier)
+    {
+        if (!$this->canBeUsedInStringContext($entryIdentifier)) {
+            throw new \InvalidArgumentException('The specified identifier is of type "' . gettype($entryIdentifier) . '" which can\'t be converted to string.', 1377006653);
+        }
+        return $this->connected && $this->redis->exists(self::IDENTIFIER_DATA_PREFIX . $entryIdentifier);
+    }
+
+    /**
+     * Removes all cache entries matching the specified identifier.
+     *
+     * Scales O(1) with number of cache entries
+     * Scales O(n) with number of tags
+     *
+     * @param string $entryIdentifier Specifies the cache entry to remove
+     * @return bool TRUE if (at least) an entry could be removed or FALSE if no entry was found
+     * @throws \InvalidArgumentException if identifier is not a string
+     */
+    public function remove($entryIdentifier)
+    {
+        if (!$this->canBeUsedInStringContext($entryIdentifier)) {
+            throw new \InvalidArgumentException('The specified identifier is of type "' . gettype($entryIdentifier) . '" which can\'t be converted to string.', 1377006654);
+        }
+        $elementsDeleted = false;
+        if ($this->connected) {
+            if ($this->redis->exists(self::IDENTIFIER_DATA_PREFIX . $entryIdentifier)) {
+                $assignedTags = $this->redis->sMembers(self::IDENTIFIER_TAGS_PREFIX . $entryIdentifier);
+                $queue = $this->redis->multi(\Redis::PIPELINE);
+                foreach ($assignedTags as $tag) {
+                    $queue->sRem(self::TAG_IDENTIFIERS_PREFIX . $tag, $entryIdentifier);
+                }
+                $queue->del(self::IDENTIFIER_DATA_PREFIX . $entryIdentifier, self::IDENTIFIER_TAGS_PREFIX . $entryIdentifier);
+                $queue->exec();
+                $elementsDeleted = true;
+            }
+        }
+        return $elementsDeleted;
+    }
+
+    /**
+     * Finds and returns all cache entry identifiers which are tagged by the
+     * specified tag.
+     *
+     * Scales O(1) with number of cache entries
+     * Scales O(n) with number of tag entries
+     *
+     * @param string $tag The tag to search for
+     * @return array An array of entries with all matching entries. An empty array if no entries matched
+     * @throws \InvalidArgumentException if tag is not a string
+     */
+    public function findIdentifiersByTag($tag)
+    {
+        if (!$this->canBeUsedInStringContext($tag)) {
+            throw new \InvalidArgumentException('The specified tag is of type "' . gettype($tag) . '" which can\'t be converted to string.', 1377006655);
+        }
+        $foundIdentifiers = [];
+        if ($this->connected) {
+            $foundIdentifiers = $this->redis->sMembers(self::TAG_IDENTIFIERS_PREFIX . $tag);
+        }
+        return $foundIdentifiers;
+    }
+
+    /**
+     * Removes all cache entries of this cache.
+     *
+     * Scales O(1) with number of cache entries
+     */
+    public function flush()
+    {
+        if ($this->connected) {
+            $this->redis->flushDB();
+        }
+    }
+
+    /**
+     * Removes all cache entries of this cache which are tagged with the specified tag.
+     *
+     * Scales O(1) with number of cache entries
+     * Scales O(n^2) with number of tag entries
+     *
+     * @param string $tag Tag the entries must have
+     * @throws \InvalidArgumentException if identifier is not a string
+     */
+    public function flushByTag($tag)
+    {
+        if (!$this->canBeUsedInStringContext($tag)) {
+            throw new \InvalidArgumentException('The specified tag is of type "' . gettype($tag) . '" which can\'t be converted to string.', 1377006656);
+        }
+        if ($this->connected) {
+            $identifiers = $this->redis->sMembers(self::TAG_IDENTIFIERS_PREFIX . $tag);
+            if (!empty($identifiers)) {
+                $this->removeIdentifierEntriesAndRelations($identifiers, [$tag]);
+            }
+        }
+    }
+
+    /**
+     * With the current internal structure, only the identifier to data entries
+     * have a redis internal lifetime. If an entry expires, attached
+     * identifier to tags and tag to identifiers entries will be left over.
+     * This methods finds those entries and cleans them up.
+     *
+     * Scales O(n*m) with number of cache entries (n) and number of tags (m)
+     */
+    public function collectGarbage()
+    {
+        $identifierToTagsKeys = $this->redis->keys(self::IDENTIFIER_TAGS_PREFIX . '*');
+        foreach ($identifierToTagsKeys as $identifierToTagsKey) {
+            list(, $identifier) = explode(':', $identifierToTagsKey);
+            // Check if the data entry still exists
+            if (!$this->redis->exists(self::IDENTIFIER_DATA_PREFIX . $identifier)) {
+                $tagsToRemoveIdentifierFrom = $this->redis->sMembers($identifierToTagsKey);
+                $queue = $this->redis->multi(\Redis::PIPELINE);
+                $queue->del($identifierToTagsKey);
+                foreach ($tagsToRemoveIdentifierFrom as $tag) {
+                    $queue->sRem(self::TAG_IDENTIFIERS_PREFIX . $tag, $identifier);
+                }
+                $queue->exec();
+            }
+        }
+    }
+
+    /**
+     * Helper method for flushByTag()
+     * Gets list of identifiers and tags and removes all relations of those tags
+     *
+     * Scales O(1) with number of cache entries
+     * Scales O(n^2) with number of tags
+     *
+     * @param array $identifiers List of identifiers to remove
+     * @param array $tags List of tags to be handled
+     */
+    protected function removeIdentifierEntriesAndRelations(array $identifiers, array $tags)
+    {
+        // Set a temporary entry which holds all identifiers that need to be removed from
+        // the tag to identifiers sets
+        $uniqueTempKey = 'temp:' . StringUtility::getUniqueId();
+        $prefixedKeysToDelete = [$uniqueTempKey];
+        $prefixedIdentifierToTagsKeysToDelete = [];
+        foreach ($identifiers as $identifier) {
+            $prefixedKeysToDelete[] = self::IDENTIFIER_DATA_PREFIX . $identifier;
+            $prefixedIdentifierToTagsKeysToDelete[] = self::IDENTIFIER_TAGS_PREFIX . $identifier;
+        }
+        foreach ($tags as $tag) {
+            $prefixedKeysToDelete[] = self::TAG_IDENTIFIERS_PREFIX . $tag;
+        }
+        $tagToIdentifiersSetsToRemoveIdentifiersFrom = $this->redis->sUnion($prefixedIdentifierToTagsKeysToDelete);
+        // Remove the tag to identifier set of the given tags, they will be removed anyway
+        $tagToIdentifiersSetsToRemoveIdentifiersFrom = array_diff($tagToIdentifiersSetsToRemoveIdentifiersFrom, $tags);
+        // Diff all identifiers that must be removed from tag to identifiers sets off from a
+        // tag to identifiers set and store result in same tag to identifiers set again
+        $queue = $this->redis->multi(\Redis::PIPELINE);
+        foreach ($identifiers as $identifier) {
+            $queue->sAdd($uniqueTempKey, $identifier);
+        }
+        foreach ($tagToIdentifiersSetsToRemoveIdentifiersFrom as $tagToIdentifiersSet) {
+            $queue->sDiffStore(self::TAG_IDENTIFIERS_PREFIX . $tagToIdentifiersSet, self::TAG_IDENTIFIERS_PREFIX . $tagToIdentifiersSet, $uniqueTempKey);
+        }
+        $queue->del(array_merge($prefixedKeysToDelete, $prefixedIdentifierToTagsKeysToDelete));
+        $queue->exec();
+    }
+
+    /**
+     * Helper method to catch invalid identifiers and tags
+     *
+     * @param mixed $variable Variable to be checked
+     * @return bool
+     */
+    protected function canBeUsedInStringContext($variable)
+    {
+        return is_scalar($variable) || (is_object($variable) && method_exists($variable, '__toString'));
+    }
+}

typo3/sysext/core/Classes/Cache/Backend/SimpleFileBackend.php

@@ -0,0 +1,368 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Backend;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Cache\Exception;
+use TYPO3\CMS\Core\Cache\Exception\InvalidDataException;
+use TYPO3\CMS\Core\Cache\Frontend\FrontendInterface;
+use TYPO3\CMS\Core\Cache\Frontend\PhpFrontend;
+use TYPO3\CMS\Core\Core\Environment;
+use TYPO3\CMS\Core\Service\OpcodeCacheService;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3\CMS\Core\Utility\PathUtility;
+use TYPO3\CMS\Core\Utility\StringUtility;
+
+/**
+ * A caching backend which stores cache entries in files, but does not support or
+ * care about expiry times and tags.
+ */
+class SimpleFileBackend extends AbstractBackend implements PhpCapableBackendInterface
+{
+    const SEPARATOR = '^';
+    const EXPIRYTIME_FORMAT = 'YmdHis';
+    const EXPIRYTIME_LENGTH = 14;
+    const DATASIZE_DIGITS = 10;
+    /**
+     * Directory where the files are stored
+     *
+     * @var string
+     */
+    protected $cacheDirectory = '';
+
+    /**
+     * Temporary path to cache directory before setCache() was called. It is
+     * set by setCacheDirectory() and used in setCache() method which calls
+     * the directory creation if needed. The variable is not used afterwards,
+     * the final cache directory path is stored in $this->cacheDirectory then.
+     *
+     * @var string Temporary path to cache directory
+     */
+    protected $temporaryCacheDirectory = '';
+
+    /**
+     * A file extension to use for each cache entry.
+     *
+     * @var string
+     */
+    protected $cacheEntryFileExtension = '';
+
+    /**
+     * @var array
+     */
+    protected $cacheEntryIdentifiers = [];
+
+    /**
+     * @var bool
+     */
+    protected $frozen = false;
+
+    /**
+     * Sets a reference to the cache frontend which uses this backend and
+     * initializes the default cache directory.
+     *
+     * @param FrontendInterface $cache The cache frontend
+     * @throws Exception
+     */
+    public function setCache(FrontendInterface $cache)
+    {
+        parent::setCache($cache);
+        if (empty($this->temporaryCacheDirectory)) {
+            // If no cache directory was given with cacheDirectory
+            // configuration option, set it to a path below var/ folder
+            $temporaryCacheDirectory = Environment::getVarPath() . '/';
+        } else {
+            $temporaryCacheDirectory = $this->temporaryCacheDirectory;
+        }
+        $codeOrData = $cache instanceof PhpFrontend ? 'code' : 'data';
+        $finalCacheDirectory = $temporaryCacheDirectory . 'cache/' . $codeOrData . '/' . $this->cacheIdentifier . '/';
+        if (!is_dir($finalCacheDirectory)) {
+            $this->createFinalCacheDirectory($finalCacheDirectory);
+        }
+        unset($this->temporaryCacheDirectory);
+        $this->cacheDirectory = $finalCacheDirectory;
+        $this->cacheEntryFileExtension = $cache instanceof PhpFrontend ? '.php' : '';
+        if (strlen($this->cacheDirectory) + 23 > PHP_MAXPATHLEN) {
+            throw new Exception('The length of the temporary cache file path "' . $this->cacheDirectory . '" exceeds the ' . 'maximum path length of ' . (PHP_MAXPATHLEN - 23) . '. Please consider ' . 'setting the temporaryDirectoryBase option to a shorter path.', 1248710426);
+        }
+    }
+
+    /**
+     * Sets the directory where the cache files are stored. By default it is
+     * assumed that the directory is below TYPO3's Project Path. However, an
+     * absolute path can be selected, too.
+     *
+     * This method enables to use a cache path outside of TYPO3's Project Path. The final
+     * cache path is checked and created in createFinalCacheDirectory(),
+     * called by setCache() method, which is done _after_ the cacheDirectory
+     * option was handled.
+     *
+     * @param string $cacheDirectory The cache base directory. If a relative path
+     * @throws Exception if the directory is not within allowed
+     */
+    public function setCacheDirectory($cacheDirectory)
+    {
+        // Skip handling if directory is a stream ressource
+        // This is used by unit tests with vfs:// directories
+        if (strpos($cacheDirectory, '://')) {
+            $this->temporaryCacheDirectory = $cacheDirectory;
+            return;
+        }
+        $documentRoot = Environment::getProjectPath() . '/';
+        if ($open_basedir = ini_get('open_basedir')) {
+            if (Environment::isWindows()) {
+                $delimiter = ';';
+                $cacheDirectory = str_replace('\\', '/', $cacheDirectory);
+                if (!preg_match('/[A-Z]:/', substr($cacheDirectory, 0, 2))) {
+                    $cacheDirectory = Environment::getProjectPath() . $cacheDirectory;
+                }
+            } else {
+                $delimiter = ':';
+                if ($cacheDirectory[0] !== '/') {
+                    // relative path to cache directory.
+                    $cacheDirectory = Environment::getProjectPath() . $cacheDirectory;
+                }
+            }
+            $basedirs = explode($delimiter, $open_basedir);
+            $cacheDirectoryInBaseDir = false;
+            foreach ($basedirs as $basedir) {
+                if (Environment::isWindows()) {
+                    $basedir = str_replace('\\', '/', $basedir);
+                }
+                if ($basedir[strlen($basedir) - 1] !== '/') {
+                    $basedir .= '/';
+                }
+                if (GeneralUtility::isFirstPartOfStr($cacheDirectory, $basedir)) {
+                    $documentRoot = $basedir;
+                    $cacheDirectory = str_replace($basedir, '', $cacheDirectory);
+                    $cacheDirectoryInBaseDir = true;
+                    break;
+                }
+            }
+            if (!$cacheDirectoryInBaseDir) {
+                throw new Exception(
+                    'Open_basedir restriction in effect. The directory "' . $cacheDirectory . '" is not in an allowed path.',
+                    1476045417
+                );
+            }
+        } else {
+            if ($cacheDirectory[0] === '/') {
+                // Absolute path to cache directory.
+                $documentRoot = '';
+            }
+            if (Environment::isWindows()) {
+                if (!empty($documentRoot) && strpos($cacheDirectory, $documentRoot) === 0) {
+                    $documentRoot = '';
+                }
+            }
+        }
+        // After this point all paths have '/' as directory separator
+        if ($cacheDirectory[strlen($cacheDirectory) - 1] !== '/') {
+            $cacheDirectory .= '/';
+        }
+        $this->temporaryCacheDirectory = $documentRoot . $cacheDirectory;
+    }
+
+    /**
+     * Create the final cache directory if it does not exist.
+     *
+     * @param string $finalCacheDirectory Absolute path to final cache directory
+     * @throws Exception If directory is not writable after creation
+     */
+    protected function createFinalCacheDirectory($finalCacheDirectory)
+    {
+        try {
+            GeneralUtility::mkdir_deep($finalCacheDirectory);
+        } catch (\RuntimeException $e) {
+            throw new Exception('The directory "' . $finalCacheDirectory . '" can not be created.', 1303669848, $e);
+        }
+        if (!is_writable($finalCacheDirectory)) {
+            throw new Exception('The directory "' . $finalCacheDirectory . '" is not writable.', 1203965200);
+        }
+    }
+
+    /**
+     * Returns the directory where the cache files are stored
+     *
+     * @return string Full path of the cache directory
+     */
+    public function getCacheDirectory()
+    {
+        return $this->cacheDirectory;
+    }
+
+    /**
+     * Saves data in a cache file.
+     *
+     * @param string $entryIdentifier An identifier for this specific cache entry
+     * @param string $data The data to be stored
+     * @param array $tags Tags to associate with this cache entry
+     * @param int $lifetime This cache backend does not support life times
+     * @throws Exception if the directory does not exist or is not writable or exceeds the maximum allowed path length, or if no cache frontend has been set.
+     * @throws InvalidDataException if the data to bes stored is not a string.
+     * @throws \InvalidArgumentException
+     */
+    public function set($entryIdentifier, $data, array $tags = [], $lifetime = null)
+    {
+        if (!is_string($data)) {
+            throw new InvalidDataException('The specified data is of type "' . gettype($data) . '" but a string is expected.', 1334756734);
+        }
+        if ($entryIdentifier !== PathUtility::basename($entryIdentifier)) {
+            throw new \InvalidArgumentException('The specified entry identifier must not contain a path segment.', 1334756735);
+        }
+        if ($entryIdentifier === '') {
+            throw new \InvalidArgumentException('The specified entry identifier must not be empty.', 1334756736);
+        }
+        $temporaryCacheEntryPathAndFilename = $this->cacheDirectory . StringUtility::getUniqueId() . '.temp';
+        $result = file_put_contents($temporaryCacheEntryPathAndFilename, $data);
+        GeneralUtility::fixPermissions($temporaryCacheEntryPathAndFilename);
+        if ($result === false) {
+            throw new Exception('The temporary cache file "' . $temporaryCacheEntryPathAndFilename . '" could not be written.', 1334756737);
+        }
+        $cacheEntryPathAndFilename = $this->cacheDirectory . $entryIdentifier . $this->cacheEntryFileExtension;
+        rename($temporaryCacheEntryPathAndFilename, $cacheEntryPathAndFilename);
+        if ($this->cacheEntryFileExtension === '.php') {
+            GeneralUtility::makeInstance(OpcodeCacheService::class)->clearAllActive($cacheEntryPathAndFilename);
+        }
+    }
+
+    /**
+     * Loads data from a cache file.
+     *
+     * @param string $entryIdentifier An identifier which describes the cache entry to load
+     * @return mixed The cache entry's content as a string or FALSE if the cache entry could not be loaded
+     * @throws \InvalidArgumentException If identifier is invalid
+     */
+    public function get($entryIdentifier)
+    {
+        if ($entryIdentifier !== PathUtility::basename($entryIdentifier)) {
+            throw new \InvalidArgumentException('The specified entry identifier must not contain a path segment.', 1334756877);
+        }
+        $pathAndFilename = $this->cacheDirectory . $entryIdentifier . $this->cacheEntryFileExtension;
+        if (!file_exists($pathAndFilename)) {
+            return false;
+        }
+        return file_get_contents($pathAndFilename);
+    }
+
+    /**
+     * Checks if a cache entry with the specified identifier exists.
+     *
+     * @param string $entryIdentifier
+     * @return bool TRUE if such an entry exists, FALSE if not
+     * @throws \InvalidArgumentException
+     */
+    public function has($entryIdentifier)
+    {
+        if ($entryIdentifier !== PathUtility::basename($entryIdentifier)) {
+            throw new \InvalidArgumentException('The specified entry identifier must not contain a path segment.', 1334756878);
+        }
+        return file_exists($this->cacheDirectory . $entryIdentifier . $this->cacheEntryFileExtension);
+    }
+
+    /**
+     * Removes all cache entries matching the specified identifier.
+     * Usually this only affects one entry.
+     *
+     * @param string $entryIdentifier Specifies the cache entry to remove
+     * @return bool TRUE if (at least) an entry could be removed or FALSE if no entry was found
+     * @throws \InvalidArgumentException
+     */
+    public function remove($entryIdentifier)
+    {
+        if ($entryIdentifier !== PathUtility::basename($entryIdentifier)) {
+            throw new \InvalidArgumentException('The specified entry identifier must not contain a path segment.', 1334756960);
+        }
+        if ($entryIdentifier === '') {
+            throw new \InvalidArgumentException('The specified entry identifier must not be empty.', 1334756961);
+        }
+        try {
+            unlink($this->cacheDirectory . $entryIdentifier . $this->cacheEntryFileExtension);
+        } catch (\Exception $e) {
+            return false;
+        }
+        return true;
+    }
+
+    /**
+     * Removes all cache entries of this cache.
+     */
+    public function flush()
+    {
+        GeneralUtility::flushDirectory($this->cacheDirectory, true);
+    }
+
+    /**
+     * Checks if the given cache entry files are still valid or if their
+     * lifetime has exceeded.
+     *
+     * @param string $cacheEntryPathAndFilename
+     * @return bool
+     */
+    protected function isCacheFileExpired($cacheEntryPathAndFilename)
+    {
+        return file_exists($cacheEntryPathAndFilename) === false;
+    }
+
+    /**
+     * Not necessary
+     */
+    public function collectGarbage()
+    {
+    }
+
+    /**
+     * Tries to find the cache entry for the specified identifier.
+     *
+     * @param string $entryIdentifier The cache entry identifier
+     * @return mixed The file names (including path) as an array if one or more entries could be found, otherwise FALSE
+     */
+    protected function findCacheFilesByIdentifier($entryIdentifier)
+    {
+        $pathAndFilename = $this->cacheDirectory . $entryIdentifier . $this->cacheEntryFileExtension;
+        return file_exists($pathAndFilename) ? [$pathAndFilename] : false;
+    }
+
+    /**
+     * Loads PHP code from the cache and require_onces it right away.
+     *
+     * @param string $entryIdentifier An identifier which describes the cache entry to load
+     * @return mixed Potential return value from the include operation
+     * @throws \InvalidArgumentException
+     */
+    public function requireOnce($entryIdentifier)
+    {
+        $pathAndFilename = $this->cacheDirectory . $entryIdentifier . $this->cacheEntryFileExtension;
+        if ($entryIdentifier !== PathUtility::basename($entryIdentifier)) {
+            throw new \InvalidArgumentException('The specified entry identifier must not contain a path segment.', 1282073037);
+        }
+        return file_exists($pathAndFilename) ? require_once $pathAndFilename : false;
+    }
+
+    /**
+     * Loads PHP code from the cache and require it right away.
+     *
+     * @param string $entryIdentifier An identifier which describes the cache entry to load
+     * @return mixed Potential return value from the include operation
+     * @throws \InvalidArgumentException
+     */
+    public function require(string $entryIdentifier)
+    {
+        $pathAndFilename = $this->cacheDirectory . $entryIdentifier . $this->cacheEntryFileExtension;
+        if ($entryIdentifier !== PathUtility::basename($entryIdentifier)) {
+            throw new \InvalidArgumentException('The specified entry identifier must not contain a path segment.', 1532528267);
+        }
+        return file_exists($pathAndFilename) ? require $pathAndFilename : false;
+    }
+}

typo3/sysext/core/Classes/Cache/Backend/TaggableBackendInterface.php

@@ -0,0 +1,44 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Backend;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * A contract for a cache backend which supports tagging.
+ */
+interface TaggableBackendInterface extends BackendInterface
+{
+    /**
+     * Removes all cache entries of this cache which are tagged by the specified tag.
+     *
+     * @param string $tag The tag the entries must have
+     */
+    public function flushByTag($tag);
+
+    /**
+     * Removes all cache entries of this cache which are tagged by any of the specified tags.
+     *
+     * @param string[] $tags List of tags
+     */
+    public function flushByTags(array $tags);
+
+    /**
+     * Finds and returns all cache entry identifiers which are tagged by the
+     * specified tag
+     *
+     * @param string $tag The tag to search for
+     * @return array An array with identifiers of all matching entries. An empty array if no entries matched
+     */
+    public function findIdentifiersByTag($tag);
+}

typo3/sysext/core/Classes/Cache/Backend/TransientBackendInterface.php

@@ -0,0 +1,33 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Backend;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * A contract for a cache backends which store variables in volatile
+ * memory and as such support receiving any variable type to store.
+ *
+ * Note: respect for this contract is up to each individual frontend.
+ * The contract can be respected for a small performance boost, but
+ * the result is marginal except for cases with huge serialized
+ * data sets.
+ *
+ * Respected by the VariableFrontend which checks if the backend
+ * has this interface, in which case it allows the backend to store
+ * the value directly without serializing it to a string, and does
+ * not attempt to unserialize the string on every get() request.
+ */
+interface TransientBackendInterface extends BackendInterface
+{
+}

typo3/sysext/core/Classes/Cache/Backend/TransientMemoryBackend.php

@@ -0,0 +1,140 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Backend;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Cache\Exception;
+use TYPO3\CMS\Core\Cache\Frontend\FrontendInterface;
+
+/**
+ * A caching backend which stores cache entries during one script run.
+ */
+class TransientMemoryBackend extends AbstractBackend implements TaggableBackendInterface, TransientBackendInterface
+{
+    /**
+     * @var array
+     */
+    protected $entries = [];
+
+    /**
+     * @var array
+     */
+    protected $tagsAndEntries = [];
+
+    /**
+     * Saves data in the cache.
+     *
+     * @param string $entryIdentifier An identifier for this specific cache entry
+     * @param string $data The data to be stored
+     * @param array $tags Tags to associate with this cache entry
+     * @param int $lifetime Lifetime of this cache entry in seconds. If NULL is specified, the default lifetime is used. "0" means unlimited lifetime.
+     * @throws Exception if no cache frontend has been set.
+     */
+    public function set($entryIdentifier, $data, array $tags = [], $lifetime = null)
+    {
+        if (!$this->cache instanceof FrontendInterface) {
+            throw new Exception('No cache frontend has been set yet via setCache().', 1238244992);
+        }
+        $this->entries[$entryIdentifier] = $data;
+        foreach ($tags as $tag) {
+            $this->tagsAndEntries[$tag][$entryIdentifier] = true;
+        }
+    }
+
+    /**
+     * Loads data from the cache.
+     *
+     * @param string $entryIdentifier An identifier which describes the cache entry to load
+     * @return mixed The cache entry's content as a string or FALSE if the cache entry could not be loaded
+     */
+    public function get($entryIdentifier)
+    {
+        return $this->entries[$entryIdentifier] ?? false;
+    }
+
+    /**
+     * Checks if a cache entry with the specified identifier exists.
+     *
+     * @param string $entryIdentifier An identifier specifying the cache entry
+     * @return bool TRUE if such an entry exists, FALSE if not
+     */
+    public function has($entryIdentifier)
+    {
+        return isset($this->entries[$entryIdentifier]);
+    }
+
+    /**
+     * Removes all cache entries matching the specified identifier.
+     *
+     * @param string $entryIdentifier Specifies the cache entry to remove
+     * @return bool TRUE if the entry could be removed or FALSE if no entry was found
+     */
+    public function remove($entryIdentifier)
+    {
+        if (isset($this->entries[$entryIdentifier])) {
+            unset($this->entries[$entryIdentifier]);
+            foreach ($this->tagsAndEntries as $tag => $_) {
+                if (isset($this->tagsAndEntries[$tag][$entryIdentifier])) {
+                    unset($this->tagsAndEntries[$tag][$entryIdentifier]);
+                }
+            }
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     * Finds and returns all cache entry identifiers which are tagged by the
+     * specified tag.
+     *
+     * @param string $tag The tag to search for
+     * @return array An array with identifiers of all matching entries. An empty array if no entries matched
+     */
+    public function findIdentifiersByTag($tag)
+    {
+        if (isset($this->tagsAndEntries[$tag])) {
+            return array_keys($this->tagsAndEntries[$tag]);
+        }
+        return [];
+    }
+
+    /**
+     * Removes all cache entries of this cache.
+     */
+    public function flush()
+    {
+        $this->entries = [];
+        $this->tagsAndEntries = [];
+    }
+
+    /**
+     * Removes all cache entries of this cache which are tagged by the specified tag.
+     *
+     * @param string $tag The tag the entries must have
+     */
+    public function flushByTag($tag)
+    {
+        $identifiers = $this->findIdentifiersByTag($tag);
+        foreach ($identifiers as $identifier) {
+            $this->remove($identifier);
+        }
+    }
+
+    /**
+     * Does nothing
+     */
+    public function collectGarbage()
+    {
+    }
+}

typo3/sysext/core/Classes/Cache/Backend/Typo3DatabaseBackend.php

@@ -0,0 +1,539 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Backend;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use Doctrine\DBAL\FetchMode;
+use TYPO3\CMS\Core\Cache\Exception;
+use TYPO3\CMS\Core\Cache\Exception\InvalidDataException;
+use TYPO3\CMS\Core\Cache\Frontend\FrontendInterface;
+use TYPO3\CMS\Core\Database\Connection;
+use TYPO3\CMS\Core\Database\ConnectionPool;
+use TYPO3\CMS\Core\Utility\ExtensionManagementUtility;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * A caching backend which stores cache entries in database tables
+ */
+class Typo3DatabaseBackend extends AbstractBackend implements TaggableBackendInterface
+{
+    /**
+     * @var int Timestamp of 2038-01-01)
+     */
+    const FAKED_UNLIMITED_EXPIRE = 2145909600;
+    /**
+     * @var string Name of the cache data table
+     */
+    protected $cacheTable;
+
+    /**
+     * @var string Name of the cache tags table
+     */
+    protected $tagsTable;
+
+    /**
+     * @var bool Indicates whether data is compressed or not (requires php zlib)
+     */
+    protected $compression = false;
+
+    /**
+     * @var int -1 to 9, indicates zlib compression level: -1 = default level 6, 0 = no compression, 9 maximum compression
+     */
+    protected $compressionLevel = -1;
+
+    /**
+     * @var int Maximum lifetime to stay with expire field below FAKED_UNLIMITED_LIFETIME
+     */
+    protected $maximumLifetime;
+
+    /**
+     * Set cache frontend instance and calculate data and tags table name
+     *
+     * @param FrontendInterface $cache The frontend for this backend
+     */
+    public function setCache(FrontendInterface $cache)
+    {
+        parent::setCache($cache);
+        $this->cacheTable = 'cf_' . $this->cacheIdentifier;
+        $this->tagsTable = 'cf_' . $this->cacheIdentifier . '_tags';
+        $this->maximumLifetime = self::FAKED_UNLIMITED_EXPIRE - $GLOBALS['EXEC_TIME'];
+    }
+
+    /**
+     * Saves data in a cache file.
+     *
+     * @param string $entryIdentifier An identifier for this specific cache entry
+     * @param string $data The data to be stored
+     * @param array $tags Tags to associate with this cache entry
+     * @param int $lifetime Lifetime of this cache entry in seconds. If NULL is specified, the default lifetime is used. "0" means unlimited lifetime.
+     * @throws Exception if no cache frontend has been set.
+     * @throws InvalidDataException if the data to be stored is not a string.
+     */
+    public function set($entryIdentifier, $data, array $tags = [], $lifetime = null)
+    {
+        $this->throwExceptionIfFrontendDoesNotExist();
+        if (!is_string($data)) {
+            throw new InvalidDataException(
+                'The specified data is of type "' . gettype($data) . '" but a string is expected.',
+                1236518298
+            );
+        }
+        if ($lifetime === null) {
+            $lifetime = $this->defaultLifetime;
+        }
+        if ($lifetime === 0 || $lifetime > $this->maximumLifetime) {
+            $lifetime = $this->maximumLifetime;
+        }
+        $expires = $GLOBALS['EXEC_TIME'] + $lifetime;
+        $this->remove($entryIdentifier);
+        if ($this->compression) {
+            $data = gzcompress($data, $this->compressionLevel);
+        }
+        GeneralUtility::makeInstance(ConnectionPool::class)
+            ->getConnectionForTable($this->cacheTable)
+            ->insert(
+                $this->cacheTable,
+                [
+                    'identifier' => $entryIdentifier,
+                    'expires' => $expires,
+                    'content' => $data,
+                ],
+                [
+                    'content' => Connection::PARAM_LOB,
+                ]
+            );
+        if (!empty($tags)) {
+            $tagRows = [];
+            foreach ($tags as $tag) {
+                $tagRows[] = [$entryIdentifier, $tag];
+            }
+            GeneralUtility::makeInstance(ConnectionPool::class)
+                ->getConnectionForTable($this->tagsTable)
+                ->bulkInsert($this->tagsTable, $tagRows, ['identifier', 'tag']);
+        }
+    }
+
+    /**
+     * Loads data from a cache file.
+     *
+     * @param string $entryIdentifier An identifier which describes the cache entry to load
+     * @return mixed The cache entry's data as a string or FALSE if the cache entry could not be loaded
+     */
+    public function get($entryIdentifier)
+    {
+        $this->throwExceptionIfFrontendDoesNotExist();
+        $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)
+            ->getQueryBuilderForTable($this->cacheTable);
+        $cacheRow = $queryBuilder->select('content')
+            ->from($this->cacheTable)
+            ->where(
+                $queryBuilder->expr()->eq(
+                    'identifier',
+                    $queryBuilder->createNamedParameter($entryIdentifier, \PDO::PARAM_STR)
+                ),
+                $queryBuilder->expr()->gte(
+                    'expires',
+                    $queryBuilder->createNamedParameter($GLOBALS['EXEC_TIME'], \PDO::PARAM_INT)
+                )
+            )
+            ->execute()
+            ->fetch();
+        $content = '';
+        if (!empty($cacheRow)) {
+            $content = $cacheRow['content'];
+        }
+        if ($this->compression && (string)$content !== '') {
+            $content = gzuncompress($content);
+        }
+        return !empty($cacheRow) ? $content : false;
+    }
+
+    /**
+     * Checks if a cache entry with the specified identifier exists.
+     *
+     * @param string $entryIdentifier Specifies the identifier to check for existence
+     * @return bool TRUE if such an entry exists, FALSE if not
+     */
+    public function has($entryIdentifier)
+    {
+        $this->throwExceptionIfFrontendDoesNotExist();
+        $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)
+            ->getQueryBuilderForTable($this->cacheTable);
+        $count = $queryBuilder->count('*')
+            ->from($this->cacheTable)
+            ->where(
+                $queryBuilder->expr()->eq(
+                    'identifier',
+                    $queryBuilder->createNamedParameter($entryIdentifier, \PDO::PARAM_STR)
+                ),
+                $queryBuilder->expr()->gte(
+                    'expires',
+                    $queryBuilder->createNamedParameter($GLOBALS['EXEC_TIME'], \PDO::PARAM_INT)
+                )
+            )
+            ->execute()
+            ->fetchColumn(0);
+        return (bool)$count;
+    }
+
+    /**
+     * Removes all cache entries matching the specified identifier.
+     * Usually this only affects one entry.
+     *
+     * @param string $entryIdentifier Specifies the cache entry to remove
+     * @return bool TRUE if (at least) an entry could be removed or FALSE if no entry was found
+     */
+    public function remove($entryIdentifier)
+    {
+        $this->throwExceptionIfFrontendDoesNotExist();
+        $numberOfRowsRemoved = GeneralUtility::makeInstance(ConnectionPool::class)
+            ->getConnectionForTable($this->cacheTable)
+            ->delete(
+                $this->cacheTable,
+                ['identifier' => $entryIdentifier]
+            );
+        GeneralUtility::makeInstance(ConnectionPool::class)
+            ->getConnectionForTable($this->tagsTable)
+            ->delete(
+                $this->tagsTable,
+                ['identifier' => $entryIdentifier]
+            );
+        return (bool)$numberOfRowsRemoved;
+    }
+
+    /**
+     * Finds and returns all cache entries which are tagged by the specified tag.
+     *
+     * @param string $tag The tag to search for
+     * @return array An array with identifiers of all matching entries. An empty array if no entries matched
+     */
+    public function findIdentifiersByTag($tag)
+    {
+        $this->throwExceptionIfFrontendDoesNotExist();
+        $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)
+            ->getQueryBuilderForTable($this->tagsTable);
+        $result = $queryBuilder->select($this->cacheTable . '.identifier')
+            ->from($this->cacheTable)
+            ->from($this->tagsTable)
+            ->where(
+                $queryBuilder->expr()->eq($this->cacheTable . '.identifier', $queryBuilder->quoteIdentifier($this->tagsTable . '.identifier')),
+                $queryBuilder->expr()->eq(
+                    $this->tagsTable . '.tag',
+                    $queryBuilder->createNamedParameter($tag, \PDO::PARAM_STR)
+                ),
+                $queryBuilder->expr()->gte(
+                    $this->cacheTable . '.expires',
+                    $queryBuilder->createNamedParameter($GLOBALS['EXEC_TIME'], \PDO::PARAM_INT)
+                )
+            )
+            ->groupBy($this->cacheTable . '.identifier')
+            ->execute();
+        $identifiers = $result->fetchAll(FetchMode::COLUMN, 0);
+        return array_combine($identifiers, $identifiers);
+    }
+
+    /**
+     * Removes all cache entries of this cache.
+     */
+    public function flush()
+    {
+        $this->throwExceptionIfFrontendDoesNotExist();
+        GeneralUtility::makeInstance(ConnectionPool::class)
+            ->getConnectionForTable($this->cacheTable)
+            ->truncate($this->cacheTable);
+        GeneralUtility::makeInstance(ConnectionPool::class)
+            ->getConnectionForTable($this->tagsTable)
+            ->truncate($this->tagsTable);
+    }
+
+    /**
+     * Removes all entries tagged by any of the specified tags. Performs the SQL
+     * operation as a bulk query for better performance.
+     *
+     * @param string[] $tags
+     */
+    public function flushByTags(array $tags)
+    {
+        $this->throwExceptionIfFrontendDoesNotExist();
+
+        if (empty($tags)) {
+            return;
+        }
+
+        /** @var Connection $connection */
+        $connection = GeneralUtility::makeInstance(ConnectionPool::class)->getConnectionForTable($this->cacheTable);
+
+        // A large set of tags was detected. Process it in chunks to guard against exceeding
+        // maximum SQL query limits.
+        if (count($tags) > 100) {
+            array_walk(array_chunk($tags, 100), [$this, 'flushByTags']);
+            return;
+        }
+        // VERY simple quoting of tags is sufficient here for performance. Tags are already
+        // validated to not contain any bad characters, e.g. they are automatically generated
+        // inside this class and suffixed with a pure integer enforced by DB.
+        $quotedTagList = array_map(function ($value) {
+            return '\'' . $value . '\'';
+        }, $tags);
+
+        if ($this->isConnectionMysql($connection)) {
+            // Use a optimized query on mysql ... don't use on your own
+            // * ansi sql does not know about multi table delete
+            // * doctrine query builder does not support join on delete()
+            $connection->executeQuery(
+                'DELETE tags2, cache1'
+                . ' FROM ' . $this->tagsTable . ' AS tags1'
+                . ' JOIN ' . $this->tagsTable . ' AS tags2 ON tags1.identifier = tags2.identifier'
+                . ' JOIN ' . $this->cacheTable . ' AS cache1 ON tags1.identifier = cache1.identifier'
+                . ' WHERE tags1.tag IN (' . implode(',', $quotedTagList) . ')'
+            );
+        } else {
+            $queryBuilder = $connection->createQueryBuilder();
+            $result = $queryBuilder->select('identifier')
+                ->from($this->tagsTable)
+                ->where('tag IN (' . implode(',', $quotedTagList) . ')')
+                // group by is like DISTINCT and used here to suppress possible duplicate identifiers
+                ->groupBy('identifier')
+                ->execute();
+            $cacheEntryIdentifiers = $result->fetchAll(FetchMode::COLUMN, 0);
+            $quotedIdentifiers = $queryBuilder->createNamedParameter($cacheEntryIdentifiers, Connection::PARAM_STR_ARRAY);
+            $queryBuilder->delete($this->cacheTable)
+                ->where($queryBuilder->expr()->in('identifier', $quotedIdentifiers))
+                ->execute();
+            $queryBuilder->delete($this->tagsTable)
+                ->where($queryBuilder->expr()->in('identifier', $quotedIdentifiers))
+                ->execute();
+        }
+    }
+
+    /**
+     * Removes all cache entries of this cache which are tagged by the specified tag.
+     *
+     * @param string $tag The tag the entries must have
+     */
+    public function flushByTag($tag)
+    {
+        $this->throwExceptionIfFrontendDoesNotExist();
+
+        if (empty($tag)) {
+            return;
+        }
+
+        /** @var Connection $connection */
+        $connection = GeneralUtility::makeInstance(ConnectionPool::class)->getConnectionForTable($this->cacheTable);
+
+        $quotedTag = '\'' . $tag . '\'';
+
+        if ($this->isConnectionMysql($connection)) {
+            // Use a optimized query on mysql ... don't use on your own
+            // * ansi sql does not know about multi table delete
+            // * doctrine query builder does not support join on delete()
+            $connection->executeQuery(
+                'DELETE tags2, cache1'
+                . ' FROM ' . $this->tagsTable . ' AS tags1'
+                . ' JOIN ' . $this->tagsTable . ' AS tags2 ON tags1.identifier = tags2.identifier'
+                . ' JOIN ' . $this->cacheTable . ' AS cache1 ON tags1.identifier = cache1.identifier'
+                . ' WHERE tags1.tag = ' . $quotedTag
+            );
+        } else {
+            $queryBuilder = $connection->createQueryBuilder();
+            $result = $queryBuilder->select('identifier')
+                ->from($this->tagsTable)
+                ->where('tag = ' . $quotedTag)
+                // group by is like DISTINCT and used here to suppress possible duplicate identifiers
+                ->groupBy('identifier')
+                ->execute();
+            $cacheEntryIdentifiers = $result->fetchAll(FetchMode::COLUMN, 0);
+            $quotedIdentifiers = $queryBuilder->createNamedParameter($cacheEntryIdentifiers, Connection::PARAM_STR_ARRAY);
+            $queryBuilder->delete($this->cacheTable)
+                ->where($queryBuilder->expr()->in('identifier', $quotedIdentifiers))
+                ->execute();
+            $queryBuilder->delete($this->tagsTable)
+                ->where($queryBuilder->expr()->in('identifier', $quotedIdentifiers))
+                ->execute();
+        }
+    }
+
+    /**
+     * Does garbage collection
+     */
+    public function collectGarbage()
+    {
+        $this->throwExceptionIfFrontendDoesNotExist();
+
+        $connection = GeneralUtility::makeInstance(ConnectionPool::class)->getConnectionForTable($this->cacheTable);
+        if ($this->isConnectionMysql($connection)) {
+            // Use a optimized query on mysql ... don't use on your own
+            // * ansi sql does not know about multi table delete
+            // * doctrine query builder does not support join on delete()
+            // First delete all expired rows from cache table and their connected tag rows
+            $connection->executeQuery(
+                'DELETE cache, tags'
+                . ' FROM ' . $this->cacheTable . ' AS cache'
+                . ' LEFT OUTER JOIN ' . $this->tagsTable . ' AS tags ON cache.identifier = tags.identifier'
+                . ' WHERE cache.expires < ?',
+                [(int)$GLOBALS['EXEC_TIME']]
+            );
+            // Then delete possible "orphaned" rows from tags table - tags that have no cache row for whatever reason
+            $connection->executeQuery(
+                'DELETE tags'
+                . ' FROM ' . $this->tagsTable . ' AS tags'
+                . ' LEFT OUTER JOIN ' . $this->cacheTable . ' as cache ON tags.identifier = cache.identifier'
+                . ' WHERE cache.identifier IS NULL'
+            );
+        } else {
+            $queryBuilder = $connection->createQueryBuilder();
+            $result = $queryBuilder->select('identifier')
+                ->from($this->cacheTable)
+                ->where($queryBuilder->expr()->lt(
+                    'expires',
+                    $queryBuilder->createNamedParameter($GLOBALS['EXEC_TIME'], \PDO::PARAM_INT)
+                ))
+                // group by is like DISTINCT and used here to suppress possible duplicate identifiers
+                ->groupBy('identifier')
+                ->execute();
+
+            // Get identifiers of expired cache entries
+            $cacheEntryIdentifiers = $result->fetchAll(FetchMode::COLUMN, 0);
+            if (!empty($cacheEntryIdentifiers)) {
+                // Delete tag rows connected to expired cache entries
+                $quotedIdentifiers = $queryBuilder->createNamedParameter($cacheEntryIdentifiers, Connection::PARAM_STR_ARRAY);
+                $queryBuilder->delete($this->tagsTable)
+                    ->where($queryBuilder->expr()->in('identifier', $quotedIdentifiers))
+                    ->execute();
+            }
+            $queryBuilder->delete($this->cacheTable)
+                ->where($queryBuilder->expr()->lt(
+                    'expires',
+                    $queryBuilder->createNamedParameter($GLOBALS['EXEC_TIME'], \PDO::PARAM_INT)
+                ))
+                ->execute();
+
+            // Find out which "orphaned" tags rows exists that have no cache row and delete those, too.
+            $queryBuilder = $connection->createQueryBuilder();
+            $result = $queryBuilder->select('tags.identifier')
+                ->from($this->tagsTable, 'tags')
+                ->leftJoin(
+                    'tags',
+                    $this->cacheTable,
+                    'cache',
+                    $queryBuilder->expr()->eq('tags.identifier', $queryBuilder->quoteIdentifier('cache.identifier'))
+                )
+                ->where($queryBuilder->expr()->isNull('cache.identifier'))
+                ->groupBy('tags.identifier')
+                ->execute();
+            $tagsEntryIdentifiers = $result->fetchAll(FetchMode::COLUMN, 0);
+
+            if (!empty($tagsEntryIdentifiers)) {
+                $quotedIdentifiers = $queryBuilder->createNamedParameter($tagsEntryIdentifiers, Connection::PARAM_STR_ARRAY);
+                $queryBuilder->delete($this->tagsTable)
+                    ->where($queryBuilder->expr()->in('identifier', $quotedIdentifiers))
+                    ->execute();
+            }
+        }
+    }
+
+    /**
+     * Returns the table where the cache entries are stored.
+     *
+     * @return string The cache table.
+     */
+    public function getCacheTable()
+    {
+        $this->throwExceptionIfFrontendDoesNotExist();
+        return $this->cacheTable;
+    }
+
+    /**
+     * Gets the table where cache tags are stored.
+     *
+     * @return string Name of the table storing tags
+     */
+    public function getTagsTable()
+    {
+        $this->throwExceptionIfFrontendDoesNotExist();
+        return $this->tagsTable;
+    }
+
+    /**
+     * Enable data compression
+     *
+     * @param bool $compression TRUE to enable compression
+     */
+    public function setCompression($compression)
+    {
+        $this->compression = $compression;
+    }
+
+    /**
+     * Set data compression level.
+     * If compression is enabled and this is not set,
+     * gzcompress default level will be used
+     *
+     * @param int -1 to 9: Compression level
+     */
+    public function setCompressionLevel($compressionLevel)
+    {
+        if ($compressionLevel >= -1 && $compressionLevel <= 9) {
+            $this->compressionLevel = $compressionLevel;
+        }
+    }
+
+    /**
+     * This database backend uses some optimized queries for mysql
+     * to get maximum performance.
+     *
+     * @param Connection $connection
+     * @return bool
+     */
+    protected function isConnectionMysql(Connection $connection): bool
+    {
+        $serverVersion = $connection->getServerVersion();
+        return (bool)(strpos($serverVersion, 'MySQL') === 0);
+    }
+
+    /**
+     * Check if required frontend instance exists
+     *
+     * @throws Exception If there is no frontend instance in $this->cache
+     */
+    protected function throwExceptionIfFrontendDoesNotExist()
+    {
+        if (!$this->cache instanceof FrontendInterface) {
+            throw new Exception('No cache frontend has been set via setCache() yet.', 1236518288);
+        }
+    }
+
+    /**
+     * Calculate needed table definitions for this cache.
+     * This helper method is used by install tool and extension manager
+     * and is not part of the public API!
+     *
+     * @return string SQL of table definitions
+     */
+    public function getTableDefinitions()
+    {
+        $cacheTableSql = file_get_contents(
+            ExtensionManagementUtility::extPath('core') .
+            'Resources/Private/Sql/Cache/Backend/Typo3DatabaseBackendCache.sql'
+        );
+        $requiredTableStructures = str_replace('###CACHE_TABLE###', $this->cacheTable, $cacheTableSql) . LF . LF;
+        $tagsTableSql = file_get_contents(
+            ExtensionManagementUtility::extPath('core') .
+            'Resources/Private/Sql/Cache/Backend/Typo3DatabaseBackendTags.sql'
+        );
+        $requiredTableStructures .= str_replace('###TAGS_TABLE###', $this->tagsTable, $tagsTableSql) . LF;
+        return $requiredTableStructures;
+    }
+}

typo3/sysext/core/Classes/Cache/Backend/WincacheBackend.php

@@ -0,0 +1,259 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Backend;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Cache\Exception;
+use TYPO3\CMS\Core\Cache\Exception\InvalidDataException;
+use TYPO3\CMS\Core\Cache\Frontend\FrontendInterface;
+
+/**
+ * A caching backend which stores cache entries by using wincache.
+ *
+ * This backend uses the following types of keys:
+ * - tag_xxx
+ * xxx is tag name, value is array of associated identifiers identifier. This
+ * is "forward" tag index. It is mainly used for obtaining content by tag
+ * (get identifier by tag -> get content by identifier)
+ * - ident_xxx
+ * xxx is identifier, value is array of associated tags. This is "reverse" tag
+ * index. It provides quick access for all tags associated with this identifier
+ * and used when removing the identifier
+ *
+ * Each key is prepended with a prefix. By default prefix consists from two parts
+ * separated by underscore character and ends in yet another underscore character:
+ * - "TYPO3"
+ * - MD5 of script path and filename and SAPI name
+ * This prefix makes sure that keys from the different installations do not
+ * conflict.
+ */
+class WincacheBackend extends AbstractBackend implements TaggableBackendInterface
+{
+    /**
+     * A prefix to separate stored data from other data possible stored in the wincache
+     *
+     * @var string
+     */
+    protected $identifierPrefix;
+
+    /**
+     * Constructs this backend
+     *
+     * @param string $context Unused, for backward compatibility only
+     * @param array $options Configuration options
+     * @throws Exception If wincache PHP extension is not loaded
+     */
+    public function __construct($context, array $options = [])
+    {
+        if (!extension_loaded('wincache')) {
+            throw new Exception('The PHP extension "wincache" must be installed and loaded in order to use the wincache backend.', 1343331520);
+        }
+        parent::__construct($context, $options);
+    }
+
+    /**
+     * Saves data in the cache
+     *
+     * @param string $entryIdentifier An identifier for this specific cache entry
+     * @param string $data The data to be stored
+     * @param array $tags Tags to associate with this cache entry
+     * @param int $lifetime Lifetime of this cache entry in seconds. If NULL is specified, the default lifetime is used. "0" means unlimited lifetime.
+     * @throws Exception if no cache frontend has been set
+     * @throws \InvalidArgumentException if the identifier is not valid
+     * @throws InvalidDataException if $data is not a string
+     */
+    public function set($entryIdentifier, $data, array $tags = [], $lifetime = null)
+    {
+        if (!$this->cache instanceof FrontendInterface) {
+            throw new Exception('No cache frontend has been set yet via setCache().', 1343331521);
+        }
+        if (!is_string($data)) {
+            throw new InvalidDataException('The specified data is of type "' . gettype($data) . '" but a string is expected.', 1343331522);
+        }
+        $tags[] = '%WCBE%' . $this->cache->getIdentifier();
+        $expiration = $lifetime ?? $this->defaultLifetime;
+        $success = wincache_ucache_set($this->identifierPrefix . $entryIdentifier, $data, $expiration);
+        if ($success === true) {
+            $this->removeIdentifierFromAllTags($entryIdentifier);
+            $this->addIdentifierToTags($entryIdentifier, $tags);
+        } else {
+            throw new Exception('Could not set value.', 1343331523);
+        }
+    }
+
+    /**
+     * Loads data from the cache
+     *
+     * @param string $entryIdentifier An identifier which describes the cache entry to load
+     * @return mixed The cache entry's content as a string or FALSE if the cache entry could not be loaded
+     */
+    public function get($entryIdentifier)
+    {
+        $success = false;
+        $value = wincache_ucache_get($this->identifierPrefix . $entryIdentifier, $success);
+        return $success ? $value : $success;
+    }
+
+    /**
+     * Checks if a cache entry with the specified identifier exists
+     *
+     * @param string $entryIdentifier An identifier specifying the cache entry
+     * @return bool TRUE if such an entry exists, FALSE if not
+     */
+    public function has($entryIdentifier)
+    {
+        return wincache_ucache_exists($this->identifierPrefix . $entryIdentifier);
+    }
+
+    /**
+     * Removes all cache entries matching the specified identifier.
+     * Usually this only affects one entry but if - for what reason ever -
+     * old entries for the identifier still exist, they are removed as well.
+     *
+     * @param string $entryIdentifier Specifies the cache entry to remove
+     * @return bool TRUE if (at least) an entry could be removed or FALSE if no entry was found
+     */
+    public function remove($entryIdentifier)
+    {
+        $this->removeIdentifierFromAllTags($entryIdentifier);
+        return wincache_ucache_delete($this->identifierPrefix . $entryIdentifier);
+    }
+
+    /**
+     * Finds and returns all cache entry identifiers which are tagged by the
+     * specified tag.
+     *
+     * @param string $tag The tag to search for
+     * @return array An array with identifiers of all matching entries. An empty array if no entries matched
+     */
+    public function findIdentifiersByTag($tag)
+    {
+        $success = false;
+        $identifiers = wincache_ucache_get($this->identifierPrefix . 'tag_' . $tag, $success);
+        if ($success === false) {
+            return [];
+        }
+        return (array)$identifiers;
+    }
+
+    /**
+     * Finds all tags for the given identifier. This function uses reverse tag
+     * index to search for tags.
+     *
+     * @param string $identifier Identifier to find tags by
+     * @return array Array with tags
+     */
+    protected function findTagsByIdentifier($identifier)
+    {
+        $success = false;
+        $tags = wincache_ucache_get($this->identifierPrefix . 'ident_' . $identifier, $success);
+        return $success ? (array)$tags : [];
+    }
+
+    /**
+     * Removes all cache entries of this cache
+     *
+     * @throws Exception
+     */
+    public function flush()
+    {
+        if (!$this->cache instanceof FrontendInterface) {
+            throw new Exception('Yet no cache frontend has been set via setCache().', 1343331524);
+        }
+        $this->flushByTag('%WCBE%' . $this->cache->getIdentifier());
+    }
+
+    /**
+     * Removes all cache entries of this cache which are tagged by the specified
+     * tag.
+     *
+     * @param string $tag The tag the entries must have
+     */
+    public function flushByTag($tag)
+    {
+        $identifiers = $this->findIdentifiersByTag($tag);
+        foreach ($identifiers as $identifier) {
+            $this->remove($identifier);
+        }
+    }
+
+    /**
+     * Associates the identifier with the given tags
+     *
+     * @param string $entryIdentifier
+     * @param array $tags
+     */
+    protected function addIdentifierToTags($entryIdentifier, array $tags)
+    {
+        // Get identifier-to-tag index to look for updates
+        $existingTags = $this->findTagsByIdentifier($entryIdentifier);
+        $existingTagsUpdated = false;
+
+        foreach ($tags as $tag) {
+            // Update tag-to-identifier index
+            $identifiers = $this->findIdentifiersByTag($tag);
+            if (!in_array($entryIdentifier, $identifiers, true)) {
+                $identifiers[] = $entryIdentifier;
+                wincache_ucache_set($this->identifierPrefix . 'tag_' . $tag, $identifiers);
+            }
+            // Test if identifier-to-tag index needs update
+            if (!in_array($tag, $existingTags, true)) {
+                $existingTags[] = $tag;
+                $existingTagsUpdated = true;
+            }
+        }
+
+        // Update identifier-to-tag index if needed
+        if ($existingTagsUpdated) {
+            wincache_ucache_set($this->identifierPrefix . 'ident_' . $entryIdentifier, $existingTags);
+        }
+    }
+
+    /**
+     * Removes association of the identifier with the given tags
+     *
+     * @param string $entryIdentifier
+     */
+    protected function removeIdentifierFromAllTags($entryIdentifier)
+    {
+        // Get tags for this identifier
+        $tags = $this->findTagsByIdentifier($entryIdentifier);
+        // Deassociate tags with this identifier
+        foreach ($tags as $tag) {
+            $identifiers = $this->findIdentifiersByTag($tag);
+            // Formally array_search() below should never return false due to
+            // the behavior of findTagsByIdentifier(). But if reverse index is
+            // corrupted, we still can get 'false' from array_search(). This is
+            // not a problem because we are removing this identifier from
+            // anywhere.
+            if (($key = array_search($entryIdentifier, $identifiers)) !== false) {
+                unset($identifiers[$key]);
+                if (!empty($identifiers)) {
+                    wincache_ucache_set($this->identifierPrefix . 'tag_' . $tag, $identifiers);
+                } else {
+                    wincache_ucache_delete($this->identifierPrefix . 'tag_' . $tag);
+                }
+            }
+        }
+        // Clear reverse tag index for this identifier
+        wincache_ucache_delete($this->identifierPrefix . 'ident_' . $entryIdentifier);
+    }
+
+    /**
+     * Does nothing, as wincache does GC itself
+     */
+    public function collectGarbage()
+    {
+    }
+}

typo3/sysext/core/Classes/Cache/CacheManager.php

@@ -0,0 +1,358 @@
+<?php
+namespace TYPO3\CMS\Core\Cache;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Cache\Backend\BackendInterface;
+use TYPO3\CMS\Core\Cache\Backend\NullBackend;
+use TYPO3\CMS\Core\Cache\Backend\TransientMemoryBackend;
+use TYPO3\CMS\Core\Cache\Backend\Typo3DatabaseBackend;
+use TYPO3\CMS\Core\Cache\Exception\DuplicateIdentifierException;
+use TYPO3\CMS\Core\Cache\Exception\InvalidBackendException;
+use TYPO3\CMS\Core\Cache\Exception\InvalidCacheException;
+use TYPO3\CMS\Core\Cache\Exception\NoSuchCacheException;
+use TYPO3\CMS\Core\Cache\Exception\NoSuchCacheGroupException;
+use TYPO3\CMS\Core\Cache\Frontend\FrontendInterface;
+use TYPO3\CMS\Core\Cache\Frontend\VariableFrontend;
+use TYPO3\CMS\Core\SingletonInterface;
+
+/**
+ * The Cache Manager
+ */
+class CacheManager implements SingletonInterface
+{
+    /**
+     * @var FrontendInterface[]
+     */
+    protected $caches = [];
+
+    /**
+     * @var array
+     */
+    protected $cacheConfigurations = [];
+
+    /**
+     * Used to flush caches of a specific group
+     * is an associative array containing the group identifier as key
+     * and the identifier as an array within that group
+     * groups are set via the cache configurations of each cache.
+     *
+     * @var array
+     */
+    protected $cacheGroups = [];
+
+    /**
+     * @var array Default cache configuration as fallback
+     */
+    protected $defaultCacheConfiguration = [
+        'frontend' => VariableFrontend::class,
+        'backend' => Typo3DatabaseBackend::class,
+        'options' => [],
+        'groups' => ['all']
+    ];
+
+    /**
+     * @var bool
+     */
+    protected $disableCaching = false;
+
+    /**
+     * Used by Bootstrap to define whether the configuration has been set finally.
+     * Controls whether a deprecation warning is logged in getCache().
+     * This property will be removed in TYPO3 v10.0.
+     *
+     * @var bool
+     * @internal
+     */
+    protected $limbo = false;
+
+    /**
+     * @param bool $disableCaching
+     */
+    public function __construct(bool $disableCaching = false)
+    {
+        $this->disableCaching = $disableCaching;
+    }
+
+    /**
+     * Sets configurations for caches. The key of each entry specifies the
+     * cache identifier and the value is an array of configuration options.
+     * Possible options are:
+     *
+     * frontend
+     * backend
+     * backendOptions
+     *
+     * If one of the options is not specified, the default value is assumed.
+     * Existing cache configurations are preserved.
+     *
+     * @param array $cacheConfigurations The cache configurations to set
+     * @throws \InvalidArgumentException If $cacheConfigurations is not an array
+     */
+    public function setCacheConfigurations(array $cacheConfigurations)
+    {
+        foreach ($cacheConfigurations as $identifier => $configuration) {
+            if (!is_array($configuration)) {
+                throw new \InvalidArgumentException('The cache configuration for cache "' . $identifier . '" was not an array as expected.', 1231259656);
+            }
+            $this->cacheConfigurations[$identifier] = $configuration;
+        }
+    }
+
+    /**
+     * Registers a cache so it can be retrieved at a later point.
+     *
+     * @param FrontendInterface $cache The cache frontend to be registered
+     * @throws DuplicateIdentifierException if a cache with the given identifier has already been registered.
+     */
+    public function registerCache(FrontendInterface $cache)
+    {
+        $identifier = $cache->getIdentifier();
+        if (isset($this->caches[$identifier])) {
+            throw new DuplicateIdentifierException('A cache with identifier "' . $identifier . '" has already been registered.', 1203698223);
+        }
+        $this->caches[$identifier] = $cache;
+    }
+
+    /**
+     * Returns the cache specified by $identifier
+     *
+     * @param string $identifier Identifies which cache to return
+     * @return FrontendInterface The specified cache frontend
+     * @throws NoSuchCacheException
+     */
+    public function getCache($identifier)
+    {
+        if ($this->hasCache($identifier) === false) {
+            throw new NoSuchCacheException('A cache with identifier "' . $identifier . '" does not exist.', 1203699034);
+        }
+        if (!isset($this->caches[$identifier])) {
+            $this->createCache($identifier);
+        }
+        return $this->caches[$identifier];
+    }
+
+    /**
+     * Checks if the specified cache has been registered.
+     *
+     * @param string $identifier The identifier of the cache
+     * @return bool TRUE if a cache with the given identifier exists, otherwise FALSE
+     */
+    public function hasCache($identifier)
+    {
+        return isset($this->caches[$identifier]) || isset($this->cacheConfigurations[$identifier]);
+    }
+
+    /**
+     * Flushes all registered caches
+     */
+    public function flushCaches()
+    {
+        $this->createAllCaches();
+        foreach ($this->caches as $cache) {
+            $cache->flush();
+        }
+    }
+
+    /**
+     * Flushes all registered caches of a specific group
+     *
+     * @param string $groupIdentifier
+     * @throws NoSuchCacheGroupException
+     */
+    public function flushCachesInGroup($groupIdentifier)
+    {
+        $this->createAllCaches();
+        if (!isset($this->cacheGroups[$groupIdentifier])) {
+            throw new NoSuchCacheGroupException('No cache in the specified group \'' . $groupIdentifier . '\'', 1390334120);
+        }
+        foreach ($this->cacheGroups[$groupIdentifier] as $cacheIdentifier) {
+            if (isset($this->caches[$cacheIdentifier])) {
+                $this->caches[$cacheIdentifier]->flush();
+            }
+        }
+    }
+
+    /**
+     * Flushes entries tagged by the specified tag of all registered
+     * caches of a specific group.
+     *
+     * @param string $groupIdentifier
+     * @param string|array $tag Tag to search for
+     * @throws NoSuchCacheGroupException
+     */
+    public function flushCachesInGroupByTag($groupIdentifier, $tag)
+    {
+        if (empty($tag)) {
+            return;
+        }
+        $this->createAllCaches();
+        if (!isset($this->cacheGroups[$groupIdentifier])) {
+            throw new NoSuchCacheGroupException('No cache in the specified group \'' . $groupIdentifier . '\'', 1390337129);
+        }
+        foreach ($this->cacheGroups[$groupIdentifier] as $cacheIdentifier) {
+            if (isset($this->caches[$cacheIdentifier])) {
+                $this->caches[$cacheIdentifier]->flushByTag($tag);
+            }
+        }
+    }
+
+    /**
+     * Flushes entries tagged by any of the specified tags in all registered
+     * caches of a specific group.
+     *
+     * @param string $groupIdentifier
+     * @param string[] $tags Tags to search for
+     * @throws NoSuchCacheGroupException
+     */
+    public function flushCachesInGroupByTags($groupIdentifier, array $tags)
+    {
+        if (empty($tags)) {
+            return;
+        }
+        $this->createAllCaches();
+        if (!isset($this->cacheGroups[$groupIdentifier])) {
+            throw new NoSuchCacheGroupException('No cache in the specified group \'' . $groupIdentifier . '\'', 1390337130);
+        }
+        foreach ($this->cacheGroups[$groupIdentifier] as $cacheIdentifier) {
+            if (isset($this->caches[$cacheIdentifier])) {
+                $this->caches[$cacheIdentifier]->flushByTags($tags);
+            }
+        }
+    }
+
+    /**
+     * Flushes entries tagged by the specified tag of all registered
+     * caches.
+     *
+     * @param string $tag Tag to search for
+     */
+    public function flushCachesByTag($tag)
+    {
+        $this->createAllCaches();
+        foreach ($this->caches as $cache) {
+            $cache->flushByTag($tag);
+        }
+    }
+
+    /**
+     * Flushes entries tagged by any of the specified tags in all registered caches.
+     *
+     * @param string[] $tags Tags to search for
+     */
+    public function flushCachesByTags(array $tags)
+    {
+        $this->createAllCaches();
+        foreach ($this->caches as $cache) {
+            $cache->flushByTags($tags);
+        }
+    }
+
+    /**
+     * Instantiates all registered caches.
+     */
+    protected function createAllCaches()
+    {
+        foreach ($this->cacheConfigurations as $identifier => $_) {
+            if (!isset($this->caches[$identifier])) {
+                $this->createCache($identifier);
+            }
+        }
+    }
+
+    /**
+     * Instantiates the cache for $identifier.
+     *
+     * @param string $identifier
+     * @throws DuplicateIdentifierException
+     * @throws InvalidBackendException
+     * @throws InvalidCacheException
+     */
+    protected function createCache($identifier)
+    {
+        // @deprecated will be removed with TYPO3 v10.0
+        if ($this->limbo) {
+            trigger_error('Usage of ' . self::class . '->createCache(\'' . $identifier . '\') in ext_localconf.php will not be supported in TYPO3 v10.0.', E_USER_DEPRECATED);
+        }
+        if (isset($this->cacheConfigurations[$identifier]['frontend'])) {
+            $frontend = $this->cacheConfigurations[$identifier]['frontend'];
+        } else {
+            $frontend = $this->defaultCacheConfiguration['frontend'];
+        }
+        if (isset($this->cacheConfigurations[$identifier]['backend'])) {
+            $backend = $this->cacheConfigurations[$identifier]['backend'];
+        } else {
+            $backend = $this->defaultCacheConfiguration['backend'];
+        }
+        if (isset($this->cacheConfigurations[$identifier]['options'])) {
+            $backendOptions = $this->cacheConfigurations[$identifier]['options'];
+        } else {
+            $backendOptions = $this->defaultCacheConfiguration['options'];
+        }
+
+        if ($this->disableCaching && $backend !== TransientMemoryBackend::class) {
+            $backend = NullBackend::class;
+            $backendOptions = [];
+        }
+
+        // Add the cache identifier to the groups that it should be attached to, or use the default ones.
+        if (isset($this->cacheConfigurations[$identifier]['groups']) && is_array($this->cacheConfigurations[$identifier]['groups'])) {
+            $assignedGroups = $this->cacheConfigurations[$identifier]['groups'];
+        } else {
+            $assignedGroups = $this->defaultCacheConfiguration['groups'];
+        }
+        foreach ($assignedGroups as $groupIdentifier) {
+            if (!isset($this->cacheGroups[$groupIdentifier])) {
+                $this->cacheGroups[$groupIdentifier] = [];
+            }
+            $this->cacheGroups[$groupIdentifier][] = $identifier;
+        }
+
+        // New operator used on purpose: This class is required early during
+        // bootstrap before makeInstance() is properly set up
+        $backend = '\\' . ltrim($backend, '\\');
+        $backendInstance = new $backend('production', $backendOptions);
+        if (!$backendInstance instanceof BackendInterface) {
+            throw new InvalidBackendException('"' . $backend . '" is not a valid cache backend object.', 1464550977);
+        }
+        if (is_callable([$backendInstance, 'initializeObject'])) {
+            $backendInstance->initializeObject();
+        }
+
+        // New used on purpose, see comment above
+        $frontendInstance = new $frontend($identifier, $backendInstance);
+        if (!$frontendInstance instanceof FrontendInterface) {
+            throw new InvalidCacheException('"' . $frontend . '" is not a valid cache frontend object.', 1464550984);
+        }
+        if (is_callable([$frontendInstance, 'initializeObject'])) {
+            $frontendInstance->initializeObject();
+        }
+
+        $this->registerCache($frontendInstance);
+    }
+
+    /**
+     * Sets the limbo state
+     *
+     * If limbo is enable, then getCache() will log a deprecation warning.
+     * This method will be removed in TYPO3 v10.0.
+     *
+     * @param bool $limbo
+     * @internal
+     */
+    public function setLimbo(bool $limbo)
+    {
+        $this->limbo = $limbo;
+    }
+}

typo3/sysext/core/Classes/Cache/DatabaseSchemaService.php

@@ -0,0 +1,58 @@
+<?php
+namespace TYPO3\CMS\Core\Cache;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * This service provides the sql schema for the caching framework
+ */
+class DatabaseSchemaService
+{
+    /**
+     * Get schema SQL of required cache framework tables.
+     *
+     * This method needs ext_localconf and ext_tables loaded!
+     *
+     * @return string Cache framework SQL
+     */
+    public function getCachingFrameworkRequiredDatabaseSchema()
+    {
+        // Use new to circumvent the singleton pattern of CacheManager
+        $cacheManager = new CacheManager();
+        $cacheManager->setCacheConfigurations($GLOBALS['TYPO3_CONF_VARS']['SYS']['caching']['cacheConfigurations']);
+
+        $tableDefinitions = '';
+        foreach ($GLOBALS['TYPO3_CONF_VARS']['SYS']['caching']['cacheConfigurations'] as $cacheName => $_) {
+            $backend = $cacheManager->getCache($cacheName)->getBackend();
+            if (method_exists($backend, 'getTableDefinitions')) {
+                $tableDefinitions .= LF . $backend->getTableDefinitions();
+            }
+        }
+
+        return $tableDefinitions;
+    }
+
+    /**
+     * A slot method to inject the required caching framework database tables to the
+     * tables definitions string
+     *
+     * @param array $sqlString
+     * @return array
+     */
+    public function addCachingFrameworkRequiredDatabaseSchemaForSqlExpectedSchemaService(array $sqlString)
+    {
+        $sqlString[] = $this->getCachingFrameworkRequiredDatabaseSchema();
+        return [$sqlString];
+    }
+}

typo3/sysext/core/Classes/Cache/Exception.php

@@ -0,0 +1,22 @@
+<?php
+namespace TYPO3\CMS\Core\Cache;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * A generic Cache exception
+ */
+class Exception extends \Exception
+{
+}

typo3/sysext/core/Classes/Cache/Exception/DuplicateIdentifierException.php

@@ -0,0 +1,22 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Exception;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * A "Duplicate Identifier" exception
+ */
+class DuplicateIdentifierException extends \TYPO3\CMS\Core\Cache\Exception
+{
+}

typo3/sysext/core/Classes/Cache/Exception/InvalidBackendException.php

@@ -0,0 +1,22 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Exception;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * An "Invalid Backend" exception
+ */
+class InvalidBackendException extends \TYPO3\CMS\Core\Cache\Exception
+{
+}

typo3/sysext/core/Classes/Cache/Exception/InvalidCacheException.php

@@ -0,0 +1,22 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Exception;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * An "Invalid Cache" exception
+ */
+class InvalidCacheException extends \TYPO3\CMS\Core\Cache\Exception
+{
+}

typo3/sysext/core/Classes/Cache/Exception/InvalidDataException.php

@@ -0,0 +1,22 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Exception;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * An "Invalid Data" exception
+ */
+class InvalidDataException extends \TYPO3\CMS\Core\Cache\Exception
+{
+}

typo3/sysext/core/Classes/Cache/Exception/NoSuchCacheException.php

@@ -0,0 +1,22 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Exception;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * A "No Such Cache" exception
+ */
+class NoSuchCacheException extends \TYPO3\CMS\Core\Cache\Exception
+{
+}

typo3/sysext/core/Classes/Cache/Exception/NoSuchCacheGroupException.php

@@ -0,0 +1,22 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Exception;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * A "No Such Cache Group" exception
+ */
+class NoSuchCacheGroupException extends \TYPO3\CMS\Core\Cache\Exception
+{
+}

typo3/sysext/core/Classes/Cache/Frontend/AbstractFrontend.php

@@ -0,0 +1,191 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Frontend;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Cache\Backend\AbstractBackend;
+use TYPO3\CMS\Core\Cache\Backend\BackendInterface;
+use TYPO3\CMS\Core\Cache\Backend\TaggableBackendInterface;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * An abstract cache
+ */
+abstract class AbstractFrontend implements FrontendInterface
+{
+    /**
+     * Identifies this cache
+     *
+     * @var string
+     */
+    protected $identifier;
+
+    /**
+     * @var AbstractBackend|TaggableBackendInterface
+     */
+    protected $backend;
+
+    /**
+     * Constructs the cache
+     *
+     * @param string $identifier An identifier which describes this cache
+     * @param BackendInterface $backend Backend to be used for this cache
+     * @throws \InvalidArgumentException if the identifier doesn't match PATTERN_ENTRYIDENTIFIER
+     */
+    public function __construct($identifier, BackendInterface $backend)
+    {
+        if (preg_match(self::PATTERN_ENTRYIDENTIFIER, $identifier) !== 1) {
+            throw new \InvalidArgumentException('"' . $identifier . '" is not a valid cache identifier.', 1203584729);
+        }
+        $this->identifier = $identifier;
+        $this->backend = $backend;
+        $this->backend->setCache($this);
+    }
+
+    /**
+     * Returns this cache's identifier
+     *
+     * @return string The identifier for this cache
+     */
+    public function getIdentifier()
+    {
+        return $this->identifier;
+    }
+
+    /**
+     * Returns the backend used by this cache
+     *
+     * @return BackendInterface The backend used by this cache
+     */
+    public function getBackend()
+    {
+        return $this->backend;
+    }
+
+    /**
+     * Checks if a cache entry with the specified identifier exists.
+     *
+     * @param string $entryIdentifier An identifier specifying the cache entry
+     * @return bool TRUE if such an entry exists, FALSE if not
+     * @throws \InvalidArgumentException If $entryIdentifier is invalid
+     */
+    public function has($entryIdentifier)
+    {
+        if (!$this->isValidEntryIdentifier($entryIdentifier)) {
+            throw new \InvalidArgumentException('"' . $entryIdentifier . '" is not a valid cache entry identifier.', 1233058486);
+        }
+        return $this->backend->has($entryIdentifier);
+    }
+
+    /**
+     * Removes the given cache entry from the cache.
+     *
+     * @param string $entryIdentifier An identifier specifying the cache entry
+     * @return bool TRUE if such an entry exists, FALSE if not
+     * @throws \InvalidArgumentException
+     */
+    public function remove($entryIdentifier)
+    {
+        if (!$this->isValidEntryIdentifier($entryIdentifier)) {
+            throw new \InvalidArgumentException('"' . $entryIdentifier . '" is not a valid cache entry identifier.', 1233058495);
+        }
+        return $this->backend->remove($entryIdentifier);
+    }
+
+    /**
+     * Removes all cache entries of this cache.
+     */
+    public function flush()
+    {
+        $this->backend->flush();
+    }
+
+    /**
+     * Removes all cache entries of this cache which are tagged by any of the specified tags.
+     *
+     * @param string[] $tags
+     * @throws \InvalidArgumentException
+     */
+    public function flushByTags(array $tags)
+    {
+        foreach ($tags as $tag) {
+            if (!$this->isValidTag($tag)) {
+                throw new \InvalidArgumentException('"' . $tag . '" is not a valid tag for a cache entry.', 1233057360);
+            }
+        }
+        if ($this->backend instanceof TaggableBackendInterface) {
+            $this->backend->flushByTags($tags);
+        }
+    }
+
+    /**
+     * Removes all cache entries of this cache which are tagged by the specified tag.
+     *
+     * @param string $tag The tag the entries must have
+     * @throws \InvalidArgumentException
+     */
+    public function flushByTag($tag)
+    {
+        if (!$this->isValidTag($tag)) {
+            throw new \InvalidArgumentException('"' . $tag . '" is not a valid tag for a cache entry.', 1233057359);
+        }
+
+        foreach ($GLOBALS['TYPO3_CONF_VARS']['SC_OPTIONS']['t3lib/cache/frontend/class.t3lib_cache_frontend_abstractfrontend.php']['flushByTag'] ?? [] as $_funcRef) {
+            $params = ['tag' => $tag];
+            GeneralUtility::callUserFunction($_funcRef, $params, $this);
+        }
+
+        if ($this->backend instanceof TaggableBackendInterface) {
+            $this->backend->flushByTag($tag);
+        }
+    }
+
+    /**
+     * Does garbage collection
+     */
+    public function collectGarbage()
+    {
+        $this->backend->collectGarbage();
+    }
+
+    /**
+     * Checks the validity of an entry identifier. Returns TRUE if it's valid.
+     *
+     * @param string $identifier An identifier to be checked for validity
+     * @return bool
+     */
+    public function isValidEntryIdentifier($identifier)
+    {
+        return preg_match(self::PATTERN_ENTRYIDENTIFIER, $identifier) === 1;
+    }
+
+    /**
+     * Checks the validity of a tag. Returns TRUE if it's valid.
+     *
+     * @param string|array $tag An identifier to be checked for validity
+     * @return bool
+     */
+    public function isValidTag($tag)
+    {
+        if (!is_array($tag)) {
+            return preg_match(self::PATTERN_TAG, $tag) === 1;
+        }
+        foreach ($tag as $tagValue) {
+            if (!$this->isValidTag($tagValue)) {
+                return false;
+            }
+        }
+        return true;
+    }
+}

typo3/sysext/core/Classes/Cache/Frontend/FrontendInterface.php

@@ -0,0 +1,125 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Frontend;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * Contract for a Cache (frontend)
+ */
+interface FrontendInterface
+{
+    /**
+     * "Magic" tag for class-related entries
+     */
+    const TAG_CLASS = '%CLASS%';
+    /**
+     * "Magic" tag for package-related entries
+     */
+    const TAG_PACKAGE = '%PACKAGE%';
+    /**
+     * Pattern an entry identifer must match.
+     */
+    const PATTERN_ENTRYIDENTIFIER = '/^[a-zA-Z0-9_%\\-&]{1,250}$/';
+    /**
+     * Pattern a tag must match.
+     */
+    const PATTERN_TAG = '/^[a-zA-Z0-9_%\\-&]{1,250}$/';
+    /**
+     * Returns this cache's identifier
+     *
+     * @return string The identifier for this cache
+     */
+    public function getIdentifier();
+
+    /**
+     * Returns the backend used by this cache
+     *
+     * @return \TYPO3\CMS\Core\Cache\Backend\BackendInterface The backend used by this cache
+     */
+    public function getBackend();
+
+    /**
+     * Saves data in the cache.
+     *
+     * @param string $entryIdentifier Something which identifies the data - depends on concrete cache
+     * @param mixed $data The data to cache - also depends on the concrete cache implementation
+     * @param array $tags Tags to associate with this cache entry
+     * @param int $lifetime Lifetime of this cache entry in seconds. If NULL is specified, the default lifetime is used. "0" means unlimited lifetime.
+     */
+    public function set($entryIdentifier, $data, array $tags = [], $lifetime = null);
+
+    /**
+     * Finds and returns data from the cache.
+     *
+     * @param string $entryIdentifier Something which identifies the cache entry - depends on concrete cache
+     * @return mixed
+     */
+    public function get($entryIdentifier);
+
+    /**
+     * Checks if a cache entry with the specified identifier exists.
+     *
+     * @param string $entryIdentifier An identifier specifying the cache entry
+     * @return bool TRUE if such an entry exists, FALSE if not
+     */
+    public function has($entryIdentifier);
+
+    /**
+     * Removes the given cache entry from the cache.
+     *
+     * @param string $entryIdentifier An identifier specifying the cache entry
+     * @return bool TRUE if such an entry exists, FALSE if not
+     */
+    public function remove($entryIdentifier);
+
+    /**
+     * Removes all cache entries of this cache.
+     */
+    public function flush();
+
+    /**
+     * Removes all cache entries of this cache which are tagged by the specified tag.
+     *
+     * @param string $tag The tag the entries must have
+     */
+    public function flushByTag($tag);
+
+    /**
+     * Removes all cache entries of this cache which are tagged by any of the specified tags.
+     *
+     * @param string[] $tags List of tags
+     */
+    public function flushByTags(array $tags);
+
+    /**
+     * Does garbage collection
+     */
+    public function collectGarbage();
+
+    /**
+     * Checks the validity of an entry identifier. Returns TRUE if it's valid.
+     *
+     * @param string $identifier An identifier to be checked for validity
+     * @return bool
+     */
+    public function isValidEntryIdentifier($identifier);
+
+    /**
+     * Checks the validity of a tag. Returns TRUE if it's valid.
+     *
+     * @param string $tag A tag to be checked for validity
+     * @return bool
+     */
+    public function isValidTag($tag);
+}

typo3/sysext/core/Classes/Cache/Frontend/PhpFrontend.php

@@ -0,0 +1,124 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Frontend;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Cache\Backend\PhpCapableBackendInterface;
+use TYPO3\CMS\Core\Cache\Exception\InvalidDataException;
+
+/**
+ * A cache frontend tailored to PHP code.
+ */
+class PhpFrontend extends AbstractFrontend
+{
+    /**
+     * Constructs the cache
+     *
+     * @param string $identifier An identifier which describes this cache
+     * @param PhpCapableBackendInterface $backend Backend to be used for this cache
+     */
+    public function __construct($identifier, PhpCapableBackendInterface $backend)
+    {
+        parent::__construct($identifier, $backend);
+    }
+
+    /**
+     * Saves the PHP source code in the cache.
+     *
+     * @param string $entryIdentifier An identifier used for this cache entry, for example the class name
+     * @param string $sourceCode PHP source code
+     * @param array $tags Tags to associate with this cache entry
+     * @param int $lifetime Lifetime of this cache entry in seconds. If NULL is specified, the default lifetime is used. "0" means unlimited lifetime.
+     * @throws \InvalidArgumentException If $entryIdentifier or $tags is invalid
+     * @throws InvalidDataException If $sourceCode is not a string
+     */
+    public function set($entryIdentifier, $sourceCode, array $tags = [], $lifetime = null)
+    {
+        if (!$this->isValidEntryIdentifier($entryIdentifier)) {
+            throw new \InvalidArgumentException('"' . $entryIdentifier . '" is not a valid cache entry identifier.', 1264023823);
+        }
+        if (!is_string($sourceCode)) {
+            throw new InvalidDataException('The given source code is not a valid string.', 1264023824);
+        }
+        foreach ($tags as $tag) {
+            if (!$this->isValidTag($tag)) {
+                throw new \InvalidArgumentException('"' . $tag . '" is not a valid tag for a cache entry.', 1264023825);
+            }
+        }
+        $sourceCode = '<?php' . LF . $sourceCode . LF . '#';
+        $this->backend->set($entryIdentifier, $sourceCode, $tags, $lifetime);
+    }
+
+    /**
+     * Finds and returns a variable value from the cache.
+     *
+     * @param string $entryIdentifier Identifier of the cache entry to fetch
+     * @return string The value
+     * @throws \InvalidArgumentException if the cache identifier is not valid
+     */
+    public function get($entryIdentifier)
+    {
+        if (!$this->isValidEntryIdentifier($entryIdentifier)) {
+            throw new \InvalidArgumentException('"' . $entryIdentifier . '" is not a valid cache entry identifier.', 1233057753);
+        }
+        return $this->backend->get($entryIdentifier);
+    }
+
+    /**
+     * Finds and returns all cache entries which are tagged by the specified tag.
+     *
+     * @param string $tag The tag to search for
+     * @return array An array with the content of all matching entries. An empty array if no entries matched
+     * @throws \InvalidArgumentException if the tag is not valid
+     * @deprecated since TYPO3 v9, Avoid using this method since it is not compliant to PSR-6
+     */
+    public function getByTag($tag)
+    {
+        trigger_error('PhpFrontend->getByTag() will be removed in TYPO3 v10.0. Avoid using this method since it is not compliant to PSR-6.', E_USER_DEPRECATED);
+        if (!$this->isValidTag($tag)) {
+            throw new \InvalidArgumentException('"' . $tag . '" is not a valid tag for a cache entry.', 1233057773);
+        }
+        $entries = [];
+        $identifiers = $this->backend->findIdentifiersByTag($tag);
+        foreach ($identifiers as $identifier) {
+            $entries[] = $this->backend->get($identifier);
+        }
+        return $entries;
+    }
+
+    /**
+     * Loads PHP code from the cache and require_onces it right away.
+     *
+     * @param string $entryIdentifier An identifier which describes the cache entry to load
+     * @return mixed Potential return value from the include operation
+     */
+    public function requireOnce($entryIdentifier)
+    {
+        return $this->backend->requireOnce($entryIdentifier);
+    }
+
+    /**
+     * Loads PHP code from the cache and require() it right away. Note require()
+     * in comparison to requireOnce() is only "safe" if the cache entry only contain stuff
+     * that can be required multiple times during one request. For instance a class definition
+     * would fail here.
+     *
+     * @param string $entryIdentifier An identifier which describes the cache entry to load
+     * @return mixed Potential return value from the include operation
+     */
+    public function require(string $entryIdentifier)
+    {
+        return $this->backend->require($entryIdentifier);
+    }
+}

typo3/sysext/core/Classes/Cache/Frontend/StringFrontend.php

@@ -0,0 +1,106 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Frontend;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Cache\Backend\BackendInterface;
+use TYPO3\CMS\Core\Cache\Exception\InvalidDataException;
+
+/**
+ * A cache frontend for strings. Nothing else.
+ *
+ * @deprecated since TYPO3 v9, will be removed in TYPO3 v10.0 - use VariableFrontend instead.
+ */
+class StringFrontend extends AbstractFrontend
+{
+    /**
+     * @param string $identifier
+     * @param BackendInterface $backend
+     */
+    public function __construct($identifier, BackendInterface $backend)
+    {
+        trigger_error(
+            sprintf(
+                'Usage of class %s will be removed in TYPO3 v10.0, use %s instead',
+                static::class,
+                VariableFrontend::class
+            ),
+            E_USER_DEPRECATED
+        );
+        parent::__construct($identifier, $backend);
+    }
+
+    /**
+     * Saves the value of a PHP variable in the cache.
+     *
+     * @param string $entryIdentifier An identifier used for this cache entry
+     * @param string $string The variable to cache
+     * @param array $tags Tags to associate with this cache entry
+     * @param int $lifetime Lifetime of this cache entry in seconds. If NULL is specified, the default lifetime is used. "0" means unlimited lifetime.
+     * @throws \InvalidArgumentException if the identifier or tag is not valid
+     * @throws InvalidDataException if the variable to cache is not of type string
+     */
+    public function set($entryIdentifier, $string, array $tags = [], $lifetime = null)
+    {
+        if (!$this->isValidEntryIdentifier($entryIdentifier)) {
+            throw new \InvalidArgumentException('"' . $entryIdentifier . '" is not a valid cache entry identifier.', 1233057566);
+        }
+        if (!is_string($string)) {
+            throw new InvalidDataException('Given data is of type "' . gettype($string) . '", but a string is expected for string cache.', 1222808333);
+        }
+        foreach ($tags as $tag) {
+            if (!$this->isValidTag($tag)) {
+                throw new \InvalidArgumentException('"' . $tag . '" is not a valid tag for a cache entry.', 1233057512);
+            }
+        }
+        $this->backend->set($entryIdentifier, $string, $tags, $lifetime);
+    }
+
+    /**
+     * Finds and returns a variable value from the cache.
+     *
+     * @param string $entryIdentifier Identifier of the cache entry to fetch
+     * @return string The value
+     * @throws \InvalidArgumentException if the cache identifier is not valid
+     */
+    public function get($entryIdentifier)
+    {
+        if (!$this->isValidEntryIdentifier($entryIdentifier)) {
+            throw new \InvalidArgumentException('"' . $entryIdentifier . '" is not a valid cache entry identifier.', 1233057752);
+        }
+        return $this->backend->get($entryIdentifier);
+    }
+
+    /**
+     * Finds and returns all cache entries which are tagged by the specified tag.
+     *
+     * @param string $tag The tag to search for
+     * @return array An array with the content of all matching entries. An empty array if no entries matched
+     * @throws \InvalidArgumentException if the tag is not valid
+     * @deprecated since TYPO3 v9, Avoid using this method since it is not compliant to PSR-6
+     */
+    public function getByTag($tag)
+    {
+        trigger_error('StringFrontend->getByTag() will be removed in TYPO3 v10.0. Avoid using this method since it is not compliant to PSR-6.', E_USER_DEPRECATED);
+        if (!$this->isValidTag($tag)) {
+            throw new \InvalidArgumentException('"' . $tag . '" is not a valid tag for a cache entry.', 1233057772);
+        }
+        $entries = [];
+        $identifiers = $this->backend->findIdentifiersByTag($tag);
+        foreach ($identifiers as $identifier) {
+            $entries[] = $this->backend->get($identifier);
+        }
+        return $entries;
+    }
+}

typo3/sysext/core/Classes/Cache/Frontend/VariableFrontend.php

@@ -0,0 +1,112 @@
+<?php
+namespace TYPO3\CMS\Core\Cache\Frontend;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Cache\Backend\TransientBackendInterface;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * A cache frontend for any kinds of PHP variables
+ */
+class VariableFrontend extends AbstractFrontend
+{
+    /**
+     * Saves the value of a PHP variable in the cache. Note that the variable
+     * will be serialized if necessary.
+     *
+     * @param string $entryIdentifier An identifier used for this cache entry
+     * @param mixed $variable The variable to cache
+     * @param array $tags Tags to associate with this cache entry
+     * @param int $lifetime Lifetime of this cache entry in seconds. If NULL is specified, the default lifetime is used. "0" means unlimited lifetime.
+     * @throws \InvalidArgumentException if the identifier or tag is not valid
+     */
+    public function set($entryIdentifier, $variable, array $tags = [], $lifetime = null)
+    {
+        if (!$this->isValidEntryIdentifier($entryIdentifier)) {
+            throw new \InvalidArgumentException(
+                '"' . $entryIdentifier . '" is not a valid cache entry identifier.',
+                1233058264
+            );
+        }
+        foreach ($tags as $tag) {
+            if (!$this->isValidTag($tag)) {
+                throw new \InvalidArgumentException('"' . $tag . '" is not a valid tag for a cache entry.', 1233058269);
+            }
+        }
+
+        foreach ($GLOBALS['TYPO3_CONF_VARS']['SC_OPTIONS']['t3lib/cache/frontend/class.t3lib_cache_frontend_variablefrontend.php']['set'] ?? [] as $_funcRef) {
+            $params = [
+                'entryIdentifier' => &$entryIdentifier,
+                'variable' => &$variable,
+                'tags' => &$tags,
+                'lifetime' => &$lifetime
+            ];
+            GeneralUtility::callUserFunction($_funcRef, $params, $this);
+        }
+        if (!$this->backend instanceof TransientBackendInterface) {
+            $variable = serialize($variable);
+        }
+        $this->backend->set($entryIdentifier, $variable, $tags, $lifetime);
+    }
+
+    /**
+     * Finds and returns a variable value from the cache.
+     *
+     * @param string $entryIdentifier Identifier of the cache entry to fetch
+     *
+     * @return mixed The value
+     * @throws \InvalidArgumentException if the identifier is not valid
+     */
+    public function get($entryIdentifier)
+    {
+        if (!$this->isValidEntryIdentifier($entryIdentifier)) {
+            throw new \InvalidArgumentException(
+                '"' . $entryIdentifier . '" is not a valid cache entry identifier.',
+                1233058294
+            );
+        }
+        $rawResult = $this->backend->get($entryIdentifier);
+        if ($rawResult === false) {
+            return false;
+        }
+        return $this->backend instanceof TransientBackendInterface ? $rawResult : unserialize($rawResult);
+    }
+
+    /**
+     * Finds and returns all cache entries which are tagged by the specified tag.
+     *
+     * @param string $tag The tag to search for
+     *
+     * @return array An array with the content of all matching entries. An empty array if no entries matched
+     * @throws \InvalidArgumentException if the tag is not valid
+     * @deprecated since TYPO3 v9, Avoid using this method since it is not compliant to PSR-6
+     */
+    public function getByTag($tag)
+    {
+        trigger_error('VariableFrontend->getByTag() will be removed in TYPO3 v10.0. Avoid using this method since it is not compliant to PSR-6.', E_USER_DEPRECATED);
+        if (!$this->isValidTag($tag)) {
+            throw new \InvalidArgumentException('"' . $tag . '" is not a valid tag for a cache entry.', 1233058312);
+        }
+        $entries = [];
+        $identifiers = $this->backend->findIdentifiersByTag($tag);
+        foreach ($identifiers as $identifier) {
+            $rawResult = $this->backend->get($identifier);
+            if ($rawResult !== false) {
+                $entries[] = $this->backend instanceof TransientBackendInterface ? $rawResult : unserialize($rawResult);
+            }
+        }
+        return $entries;
+    }
+}

typo3/sysext/core/Classes/Category/CategoryRegistry.php

@@ -0,0 +1,492 @@
+<?php
+namespace TYPO3\CMS\Core\Category;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Localization\LanguageService;
+use TYPO3\CMS\Core\SingletonInterface;
+use TYPO3\CMS\Core\Utility\ArrayUtility;
+use TYPO3\CMS\Core\Utility\ExtensionManagementUtility;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * Class to register category configurations.
+ */
+class CategoryRegistry implements SingletonInterface
+{
+    /**
+     * @var array
+     */
+    protected $registry = [];
+
+    /**
+     * @var array
+     */
+    protected $extensions = [];
+
+    /**
+     * @var array
+     */
+    protected $addedCategoryTabs = [];
+
+    /**
+     * @var string
+     */
+    protected $template = '';
+
+    /**
+     * Returns a class instance
+     *
+     * @return CategoryRegistry
+     * @internal
+     */
+    public static function getInstance()
+    {
+        return GeneralUtility::makeInstance(__CLASS__);
+    }
+
+    /**
+     * Creates this object.
+     */
+    public function __construct()
+    {
+        $this->template = str_repeat(PHP_EOL, 3) . 'CREATE TABLE %s (' . PHP_EOL
+            . '  %s int(11) DEFAULT \'0\' NOT NULL' . PHP_EOL . ');' . str_repeat(PHP_EOL, 3);
+    }
+
+    /**
+     * Adds a new category configuration to this registry.
+     * TCA changes are directly applied
+     *
+     * @param string $extensionKey Extension key to be used
+     * @param string $tableName Name of the table to be registered
+     * @param string $fieldName Name of the field to be registered
+     * @param array $options Additional configuration options
+     *              + fieldList: field configuration to be added to showitems
+     *              + typesList: list of types that shall visualize the categories field
+     *              + position: insert position of the categories field
+     *              + label: backend label of the categories field
+     *              + fieldConfiguration: TCA field config array to override defaults
+     * @param bool $override If TRUE, any category configuration for the same table / field is removed before the new configuration is added
+     * @return bool
+     * @throws \InvalidArgumentException
+     * @throws \RuntimeException
+     * @internal
+     */
+    public function add($extensionKey, $tableName, $fieldName = 'categories', array $options = [], $override = false)
+    {
+        $didRegister = false;
+        if (empty($tableName) || !is_string($tableName)) {
+            throw new \InvalidArgumentException('No or invalid table name "' . $tableName . '" given.', 1369122038);
+        }
+        if (empty($extensionKey) || !is_string($extensionKey)) {
+            throw new \InvalidArgumentException('No or invalid extension key "' . $extensionKey . '" given.', 1397836158);
+        }
+
+        if ($override) {
+            $this->remove($tableName, $fieldName);
+        }
+
+        if (!$this->isRegistered($tableName, $fieldName)) {
+            $this->registry[$tableName][$fieldName] = $options;
+            $this->extensions[$extensionKey][$tableName][$fieldName] = $fieldName;
+
+            if (isset($GLOBALS['TCA'][$tableName]['columns'])) {
+                $this->applyTcaForTableAndField($tableName, $fieldName);
+                $didRegister = true;
+            }
+        }
+
+        return $didRegister;
+    }
+
+    /**
+     * Gets all extension keys that registered a category configuration.
+     *
+     * @return array
+     * @internal
+     */
+    public function getExtensionKeys()
+    {
+        return array_keys($this->extensions);
+    }
+
+    /**
+     * Gets all categorized tables
+     *
+     * @return array
+     * @internal
+     */
+    public function getCategorizedTables()
+    {
+        return array_keys($this->registry);
+    }
+
+    /**
+     * Returns a list of category fields for a given table for populating selector "category_field"
+     * in tt_content table (called as itemsProcFunc).
+     *
+     * @param array $configuration Current field configuration
+     * @throws \UnexpectedValueException
+     * @internal
+     */
+    public function getCategoryFieldsForTable(array &$configuration)
+    {
+        $table = $configuration['config']['itemsProcConfig']['table'] ?? '';
+        // Lookup table for legacy menu content element
+        if (empty($table)) {
+            $menuType = $configuration['row']['menu_type'][0] ?? '';
+            // Define the table being looked up from the type of menu
+            if ($menuType === 'categorized_pages') {
+                $table = 'pages';
+            } elseif ($menuType === 'categorized_content') {
+                $table = 'tt_content';
+            }
+        }
+        // Return early if no table is defined
+        if (empty($table)) {
+            throw new \UnexpectedValueException('The given menu_type is not supported.', 1381823570);
+        }
+        // Loop on all registries and find entries for the correct table
+        foreach ($this->registry as $tableName => $fields) {
+            if ($tableName === $table) {
+                foreach ($fields as $fieldName => $options) {
+                    $fieldLabel = $this->getLanguageService()->sL($GLOBALS['TCA'][$tableName]['columns'][$fieldName]['label']);
+                    $configuration['items'][] = [$fieldLabel, $fieldName];
+                }
+            }
+        }
+    }
+
+    /**
+     * Tells whether a table has a category configuration in the registry.
+     *
+     * @param string $tableName Name of the table to be looked up
+     * @param string $fieldName Name of the field to be looked up
+     * @return bool
+     * @internal
+     */
+    public function isRegistered($tableName, $fieldName = 'categories')
+    {
+        return isset($this->registry[$tableName][$fieldName]);
+    }
+
+    /**
+     * Generates tables definitions for all registered tables.
+     *
+     * @return string
+     * @internal
+     */
+    public function getDatabaseTableDefinitions()
+    {
+        $sql = '';
+        foreach ($this->getExtensionKeys() as $extensionKey) {
+            $sql .= $this->getDatabaseTableDefinition($extensionKey);
+        }
+        return $sql;
+    }
+
+    /**
+     * Generates table definitions for registered tables by an extension.
+     *
+     * @param string $extensionKey Extension key to have the database definitions created for
+     * @return string
+     * @internal
+     */
+    public function getDatabaseTableDefinition($extensionKey)
+    {
+        if (!isset($this->extensions[$extensionKey]) || !is_array($this->extensions[$extensionKey])) {
+            return '';
+        }
+        $sql = '';
+
+        foreach ($this->extensions[$extensionKey] as $tableName => $fields) {
+            foreach ($fields as $fieldName) {
+                $sql .= sprintf($this->template, $tableName, $fieldName);
+            }
+        }
+        return $sql;
+    }
+
+    /**
+     * Apply TCA to all registered tables
+     *
+     * @internal
+     */
+    public function applyTcaForPreRegisteredTables()
+    {
+        $this->registerDefaultCategorizedTables();
+        foreach ($this->registry as $tableName => $fields) {
+            foreach ($fields as $fieldName => $_) {
+                $this->applyTcaForTableAndField($tableName, $fieldName);
+            }
+        }
+    }
+
+    /**
+     * Applies the additions directly to the TCA
+     *
+     * @param string $tableName
+     * @param string $fieldName
+     */
+    protected function applyTcaForTableAndField($tableName, $fieldName)
+    {
+        $this->addTcaColumn($tableName, $fieldName, $this->registry[$tableName][$fieldName]);
+        $this->addToAllTCAtypes($tableName, $fieldName, $this->registry[$tableName][$fieldName]);
+    }
+
+    /**
+     * Add default categorized tables to the registry
+     */
+    protected function registerDefaultCategorizedTables()
+    {
+        $defaultCategorizedTables = GeneralUtility::trimExplode(
+            ',',
+            $GLOBALS['TYPO3_CONF_VARS']['SYS']['defaultCategorizedTables'],
+            true
+        );
+        foreach ($defaultCategorizedTables as $defaultCategorizedTable) {
+            if (!$this->isRegistered($defaultCategorizedTable)) {
+                $this->add('core', $defaultCategorizedTable, 'categories');
+            }
+        }
+    }
+
+    /**
+     * Add a new field into the TCA types -> showitem
+     *
+     * @param string $tableName Name of the table to be categorized
+     * @param string $fieldName Name of the field to be used to store categories
+     * @param array $options Additional configuration options
+     *              + fieldList: field configuration to be added to showitems
+     *              + typesList: list of types that shall visualize the categories field
+     *              + position: insert position of the categories field
+     */
+    protected function addToAllTCAtypes($tableName, $fieldName, array $options)
+    {
+
+        // Makes sure to add more TCA to an existing structure
+        if (isset($GLOBALS['TCA'][$tableName]['columns'])) {
+            if (empty($options['fieldList'])) {
+                $fieldList = $this->addCategoryTab($tableName, $fieldName);
+            } else {
+                $fieldList = $options['fieldList'];
+            }
+
+            $typesList = '';
+            if (isset($options['typesList']) && $options['typesList'] !== '') {
+                $typesList = $options['typesList'];
+            }
+
+            $position = '';
+            if (!empty($options['position'])) {
+                $position = $options['position'];
+            }
+
+            // Makes the new "categories" field to be visible in TSFE.
+            ExtensionManagementUtility::addToAllTCAtypes($tableName, $fieldList, $typesList, $position);
+        }
+    }
+
+    /**
+     * Creates the 'fieldList' string for $fieldName which includes a categories tab.
+     * But only one categories tab is added per table.
+     *
+     * @param string $tableName
+     * @param string $fieldName
+     * @return string
+     */
+    protected function addCategoryTab($tableName, $fieldName)
+    {
+        $fieldList = '';
+        if (!isset($this->addedCategoryTabs[$tableName])) {
+            $fieldList .= '--div--;LLL:EXT:core/Resources/Private/Language/locallang_tca.xlf:sys_category.tabs.category, ';
+            $this->addedCategoryTabs[$tableName] = $tableName;
+        }
+        $fieldList .= $fieldName;
+        return $fieldList;
+    }
+
+    /**
+     * Add a new TCA Column
+     *
+     * @param string $tableName Name of the table to be categorized
+     * @param string $fieldName Name of the field to be used to store categories
+     * @param array $options Additional configuration options
+     *              + fieldConfiguration: TCA field config array to override defaults
+     *              + label: backend label of the categories field
+     *              + interface: boolean if the category should be included in the "interface" section of the TCA table
+     *              + l10n_mode
+     *              + l10n_display
+     */
+    protected function addTcaColumn($tableName, $fieldName, array $options)
+    {
+        // Makes sure to add more TCA to an existing structure
+        if (isset($GLOBALS['TCA'][$tableName]['columns'])) {
+            // Take specific label into account
+            $label = 'LLL:EXT:core/Resources/Private/Language/locallang_tca.xlf:sys_category.categories';
+            if (!empty($options['label'])) {
+                $label = $options['label'];
+            }
+
+            // Take specific value of exclude flag into account
+            $exclude = true;
+            if (isset($options['exclude'])) {
+                $exclude = (bool)$options['exclude'];
+            }
+
+            $fieldConfiguration = empty($options['fieldConfiguration']) ? [] : $options['fieldConfiguration'];
+
+            $columns = [
+                $fieldName => [
+                    'exclude' => $exclude,
+                    'label' => $label,
+                    'config' =>  static::getTcaFieldConfiguration($tableName, $fieldName, $fieldConfiguration),
+                ],
+            ];
+
+            if (isset($options['l10n_mode'])) {
+                $columns[$fieldName]['l10n_mode'] = $options['l10n_mode'];
+            }
+            if (isset($options['l10n_display'])) {
+                $columns[$fieldName]['l10n_display'] = $options['l10n_display'];
+            }
+            if (isset($options['displayCond'])) {
+                $columns[$fieldName]['displayCond'] = $options['displayCond'];
+            }
+            if (isset($options['onChange'])) {
+                $columns[$fieldName]['onChange'] = $options['onChange'];
+            }
+
+            // Register opposite references for the foreign side of a relation
+            if (empty($GLOBALS['TCA']['sys_category']['columns']['items']['config']['MM_oppositeUsage'][$tableName])) {
+                $GLOBALS['TCA']['sys_category']['columns']['items']['config']['MM_oppositeUsage'][$tableName] = [];
+            }
+            if (!in_array($fieldName, $GLOBALS['TCA']['sys_category']['columns']['items']['config']['MM_oppositeUsage'][$tableName])) {
+                $GLOBALS['TCA']['sys_category']['columns']['items']['config']['MM_oppositeUsage'][$tableName][] = $fieldName;
+            }
+
+            // Add field to interface list per default (unless the 'interface' property is FALSE)
+            if (
+                (!isset($options['interface']) || $options['interface'])
+                && !empty($GLOBALS['TCA'][$tableName]['interface']['showRecordFieldList'])
+                && !GeneralUtility::inList($GLOBALS['TCA'][$tableName]['interface']['showRecordFieldList'], $fieldName)
+            ) {
+                $GLOBALS['TCA'][$tableName]['interface']['showRecordFieldList'] .= ',' . $fieldName;
+            }
+
+            // Adding fields to an existing table definition
+            ExtensionManagementUtility::addTCAcolumns($tableName, $columns);
+        }
+    }
+
+    /**
+     * Get the config array for given table and field.
+     * This method does NOT take care of adding sql fields, adding the field to TCA types
+     * nor does it set the MM_oppositeUsage in the sys_category TCA. This has to be taken care of manually!
+     *
+     * @param string $tableName The table name
+     * @param string $fieldName The field name (default categories)
+     * @param array $fieldConfigurationOverride Changes to the default configuration
+     * @return array
+     */
+    public static function getTcaFieldConfiguration($tableName, $fieldName = 'categories', array $fieldConfigurationOverride = [])
+    {
+        // Forges a new field, default name is "categories"
+        $fieldConfiguration = [
+            'type' => 'select',
+            'renderType' => 'selectTree',
+            'foreign_table' => 'sys_category',
+            'foreign_table_where' => ' AND sys_category.sys_language_uid IN (-1, 0) ORDER BY sys_category.sorting ASC',
+            'MM' => 'sys_category_record_mm',
+            'MM_opposite_field' => 'items',
+            'MM_match_fields' => [
+                'tablenames' => $tableName,
+                'fieldname' => $fieldName,
+            ],
+            'size' => 20,
+            'maxitems' => 9999,
+            'treeConfig' => [
+                'parentField' => 'parent',
+                'appearance' => [
+                    'expandAll' => true,
+                    'showHeader' => true,
+                    'maxLevels' => 99,
+                ],
+            ],
+        ];
+
+        // Merge changes to TCA configuration
+        if (!empty($fieldConfigurationOverride)) {
+            ArrayUtility::mergeRecursiveWithOverrule(
+                $fieldConfiguration,
+                $fieldConfigurationOverride
+            );
+        }
+
+        return $fieldConfiguration;
+    }
+
+    /**
+     * A slot method to inject the required category database fields to the
+     * tables definition string
+     *
+     * @param array $sqlString
+     * @return array
+     * @internal
+     */
+    public function addCategoryDatabaseSchemaToTablesDefinition(array $sqlString)
+    {
+        $this->registerDefaultCategorizedTables();
+        $sqlString[] = $this->getDatabaseTableDefinitions();
+        return ['sqlString' => $sqlString];
+    }
+
+    /**
+     * @return LanguageService
+     */
+    protected function getLanguageService()
+    {
+        return $GLOBALS['LANG'];
+    }
+
+    /**
+     * Removes the given field in the given table from the registry if it is found.
+     *
+     * @param string $tableName The name of the table for which the registration should be removed.
+     * @param string $fieldName The name of the field for which the registration should be removed.
+     */
+    protected function remove($tableName, $fieldName)
+    {
+        if (!$this->isRegistered($tableName, $fieldName)) {
+            return;
+        }
+
+        unset($this->registry[$tableName][$fieldName]);
+
+        foreach ($this->extensions as $extensionKey => $tableFieldConfig) {
+            foreach ($tableFieldConfig as $extTableName => $fieldNameArray) {
+                if ($extTableName === $tableName && isset($fieldNameArray[$fieldName])) {
+                    unset($this->extensions[$extensionKey][$tableName][$fieldName]);
+                    break;
+                }
+            }
+        }
+
+        // If no more fields are configured we unregister the categories tab.
+        if (empty($this->registry[$tableName]) && isset($this->addedCategoryTabs[$tableName])) {
+            unset($this->addedCategoryTabs[$tableName]);
+        }
+    }
+}

typo3/sysext/core/Classes/Category/Collection/CategoryCollection.php

@@ -0,0 +1,330 @@
+<?php
+namespace TYPO3\CMS\Core\Category\Collection;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Collection\AbstractRecordCollection;
+use TYPO3\CMS\Core\Collection\CollectionInterface;
+use TYPO3\CMS\Core\Collection\EditableCollectionInterface;
+use TYPO3\CMS\Core\Database\ConnectionPool;
+use TYPO3\CMS\Core\Database\Query\QueryBuilder;
+use TYPO3\CMS\Core\Database\Query\Restriction\DeletedRestriction;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * Category Collection to handle records attached to a category
+ */
+class CategoryCollection extends AbstractRecordCollection implements EditableCollectionInterface
+{
+    /**
+     * The table name collections are stored to
+     *
+     * @var string
+     */
+    protected static $storageTableName = 'sys_category';
+
+    /**
+     * Name of the categories-relation field (used in the MM_match_fields/fieldname property of the TCA)
+     *
+     * @var string
+     */
+    protected $relationFieldName = 'categories';
+
+    /**
+     * Creates this object.
+     *
+     * @param string $tableName Name of the table to be working on
+     * @param string $fieldName Name of the field where the categories relations are defined
+     * @throws \RuntimeException
+     */
+    public function __construct($tableName = null, $fieldName = null)
+    {
+        parent::__construct();
+        if (!empty($tableName)) {
+            $this->setItemTableName($tableName);
+        } elseif (empty($this->itemTableName)) {
+            throw new \RuntimeException(self::class . ' needs a valid itemTableName.', 1341826168);
+        }
+        if (!empty($fieldName)) {
+            $this->setRelationFieldName($fieldName);
+        }
+    }
+
+    /**
+     * Creates a new collection objects and reconstitutes the
+     * given database record to the new object.
+     *
+     * @param array $collectionRecord Database record
+     * @param bool $fillItems Populates the entries directly on load, might be bad for memory on large collections
+     * @return CategoryCollection
+     */
+    public static function create(array $collectionRecord, $fillItems = false)
+    {
+        /** @var CategoryCollection $collection */
+        $collection = GeneralUtility::makeInstance(
+            self::class,
+            $collectionRecord['table_name'],
+            $collectionRecord['field_name']
+        );
+        $collection->fromArray($collectionRecord);
+        if ($fillItems) {
+            $collection->loadContents();
+        }
+        return $collection;
+    }
+
+    /**
+     * Loads the collections with the given id from persistence
+     * For memory reasons, per default only f.e. title, database-table,
+     * identifier (what ever static data is defined) is loaded.
+     * Entries can be load on first access.
+     *
+     * @param int $id Id of database record to be loaded
+     * @param bool $fillItems Populates the entries directly on load, might be bad for memory on large collections
+     * @param string $tableName Name of table from which entries should be loaded
+     * @param string $fieldName Name of the categories relation field
+     * @return CollectionInterface
+     */
+    public static function load($id, $fillItems = false, $tableName = '', $fieldName = '')
+    {
+        $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)
+            ->getQueryBuilderForTable(static::$storageTableName);
+
+        $queryBuilder->getRestrictions()
+            ->removeAll()
+            ->add(GeneralUtility::makeInstance(DeletedRestriction::class));
+
+        $collectionRecord = $queryBuilder->select('*')
+            ->from(static::$storageTableName)
+            ->where(
+                $queryBuilder->expr()->eq('uid', $queryBuilder->createNamedParameter($id, \PDO::PARAM_INT))
+            )
+            ->setMaxResults(1)
+            ->execute()
+            ->fetch();
+
+        $collectionRecord['table_name'] = $tableName;
+        $collectionRecord['field_name'] = $fieldName;
+
+        return self::create($collectionRecord, $fillItems);
+    }
+
+    /**
+     * Selects the collected records in this collection, by
+     * looking up the MM relations of this record to the
+     * table name defined in the local field 'table_name'.
+     *
+     * @return QueryBuilder
+     */
+    protected function getCollectedRecordsQueryBuilder()
+    {
+        $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)
+            ->getQueryBuilderForTable(static::$storageTableName);
+        $queryBuilder->getRestrictions()->removeAll();
+
+        $queryBuilder->select($this->getItemTableName() . '.*')
+            ->from(static::$storageTableName)
+            ->join(
+                static::$storageTableName,
+                'sys_category_record_mm',
+                'sys_category_record_mm',
+                $queryBuilder->expr()->eq(
+                    'sys_category_record_mm.uid_local',
+                    $queryBuilder->quoteIdentifier(static::$storageTableName . '.uid')
+                )
+            )
+            ->join(
+                'sys_category_record_mm',
+                $this->getItemTableName(),
+                $this->getItemTableName(),
+                $queryBuilder->expr()->eq(
+                    'sys_category_record_mm.uid_foreign',
+                    $queryBuilder->quoteIdentifier($this->getItemTableName() . '.uid')
+                )
+            )
+            ->where(
+                $queryBuilder->expr()->eq(
+                    static::$storageTableName . '.uid',
+                    $queryBuilder->createNamedParameter($this->getIdentifier(), \PDO::PARAM_INT)
+                ),
+                $queryBuilder->expr()->eq(
+                    'sys_category_record_mm.tablenames',
+                    $queryBuilder->createNamedParameter($this->getItemTableName(), \PDO::PARAM_STR)
+                ),
+                $queryBuilder->expr()->eq(
+                    'sys_category_record_mm.fieldname',
+                    $queryBuilder->createNamedParameter($this->getRelationFieldName(), \PDO::PARAM_STR)
+                )
+            );
+
+        return $queryBuilder;
+    }
+
+    /**
+     * Gets the collected records in this collection, by
+     * using <getCollectedRecordsQueryBuilder>.
+     *
+     * @return array
+     */
+    protected function getCollectedRecords()
+    {
+        $relatedRecords = [];
+
+        $queryBuilder = $this->getCollectedRecordsQueryBuilder();
+        $result = $queryBuilder->execute();
+
+        while ($record = $result->fetch()) {
+            $relatedRecords[] = $record;
+        }
+
+        return $relatedRecords;
+    }
+
+    /**
+     * Populates the content-entries of the storage
+     * Queries the underlying storage for entries of the collection
+     * and adds them to the collection data.
+     * If the content entries of the storage had not been loaded on creation
+     * ($fillItems = false) this function is to be used for loading the contents
+     * afterwards.
+     */
+    public function loadContents()
+    {
+        $entries = $this->getCollectedRecords();
+        $this->removeAll();
+        foreach ($entries as $entry) {
+            $this->add($entry);
+        }
+    }
+
+    /**
+     * Returns an array of the persistable properties and contents
+     * which are processable by DataHandler.
+     * for internal usage in persist only.
+     *
+     * @return array
+     */
+    protected function getPersistableDataArray()
+    {
+        return [
+            'title' => $this->getTitle(),
+            'description' => $this->getDescription(),
+            'items' => $this->getItemUidList(true)
+        ];
+    }
+
+    /**
+     * Adds on entry to the collection
+     *
+     * @param mixed $data
+     */
+    public function add($data)
+    {
+        $this->storage->push($data);
+    }
+
+    /**
+     * Adds a set of entries to the collection
+     *
+     * @param CollectionInterface $other
+     */
+    public function addAll(CollectionInterface $other)
+    {
+        foreach ($other as $value) {
+            $this->add($value);
+        }
+    }
+
+    /**
+     * Removes the given entry from collection
+     * Note: not the given "index"
+     *
+     * @param mixed $data
+     */
+    public function remove($data)
+    {
+        $offset = 0;
+        foreach ($this->storage as $value) {
+            if ($value == $data) {
+                break;
+            }
+            $offset++;
+        }
+        $this->storage->offsetUnset($offset);
+    }
+
+    /**
+     * Removes all entries from the collection
+     * collection will be empty afterwards
+     */
+    public function removeAll()
+    {
+        $this->storage = new \SplDoublyLinkedList();
+    }
+
+    /**
+     * Gets the current available items.
+     *
+     * @return array
+     */
+    public function getItems()
+    {
+        $itemArray = [];
+        /** @var \TYPO3\CMS\Core\Resource\File $item */
+        foreach ($this->storage as $item) {
+            $itemArray[] = $item;
+        }
+        return $itemArray;
+    }
+
+    /**
+     * Sets the name of the categories relation field
+     *
+     * @param string $field
+     */
+    public function setRelationFieldName($field)
+    {
+        $this->relationFieldName = $field;
+    }
+
+    /**
+     * Gets the name of the categories relation field
+     *
+     * @return string
+     */
+    public function getRelationFieldName()
+    {
+        return $this->relationFieldName;
+    }
+
+    /**
+     * Getter for the storage table name
+     *
+     * @return string
+     */
+    public static function getStorageTableName()
+    {
+        return self::$storageTableName;
+    }
+
+    /**
+     * Getter for the storage items field
+     *
+     * @return string
+     */
+    public static function getStorageItemsField()
+    {
+        return self::$storageItemsField;
+    }
+}

typo3/sysext/core/Classes/Charset/UnknownCharsetException.php

@@ -0,0 +1,24 @@
+<?php
+namespace TYPO3\CMS\Core\Charset;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Exception;
+
+/**
+ * Exception for unknown charsets
+ */
+class UnknownCharsetException extends Exception
+{
+}

typo3/sysext/core/Classes/Collection/AbstractRecordCollection.php

@@ -0,0 +1,433 @@
+<?php
+namespace TYPO3\CMS\Core\Collection;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+use TYPO3\CMS\Core\Database\ConnectionPool;
+use TYPO3\CMS\Core\Database\Query\Restriction\DeletedRestriction;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * Abstract implementation of a RecordCollection
+ *
+ * RecordCollection is a collections of TCA-Records.
+ * The collection is meant to be stored in TCA-table sys_collections and is manageable
+ * via TCEforms.
+ *
+ * A RecordCollection might be used to group a set of records (e.g. news, images, contentElements)
+ * for output in frontend
+ *
+ * The AbstractRecordCollection uses SplDoublyLinkedList for internal storage
+ */
+abstract class AbstractRecordCollection implements RecordCollectionInterface, PersistableCollectionInterface, SortableCollectionInterface
+{
+    /**
+     * The table name collections are stored to
+     *
+     * @var string
+     */
+    protected static $storageTableName = 'sys_collection';
+
+    /**
+     * The table name collections are stored to
+     *
+     * @var string
+     */
+    protected static $storageItemsField = 'items';
+
+    /**
+     * Uid of the storage
+     *
+     * @var int
+     */
+    protected $uid = 0;
+
+    /**
+     * Collection title
+     *
+     * @var string
+     */
+    protected $title;
+
+    /**
+     * Collection description
+     *
+     * @var string
+     */
+    protected $description;
+
+    /**
+     * Table name of the records stored in this collection
+     *
+     * @var string
+     */
+    protected $itemTableName;
+
+    /**
+     * The local storage
+     *
+     * @var \SplDoublyLinkedList
+     */
+    protected $storage;
+
+    /**
+     * Creates this object.
+     */
+    public function __construct()
+    {
+        $this->storage = new \SplDoublyLinkedList();
+    }
+
+    /**
+     * (PHP 5 >= 5.1.0)
+     * Return the current element
+     *
+     * @link http://php.net/manual/en/iterator.current.php
+     * @return mixed Can return any type.
+     */
+    public function current()
+    {
+        return $this->storage->current();
+    }
+
+    /**
+     * (PHP 5 >= 5.1.0)
+     * Move forward to next element
+     *
+     * @link http://php.net/manual/en/iterator.next.php
+     */
+    public function next()
+    {
+        $this->storage->next();
+    }
+
+    /**
+     * (PHP 5 >= 5.1.0)
+     * Return the key of the current element
+     *
+     * @link http://php.net/manual/en/iterator.key.php
+     * @return int 0 on failure.
+     */
+    public function key()
+    {
+        $currentRecord = $this->storage->current();
+        return $currentRecord['uid'];
+    }
+
+    /**
+     * (PHP 5 >= 5.1.0)
+     * Checks if current position is valid
+     *
+     * @link http://php.net/manual/en/iterator.valid.php
+     * @return bool The return value will be casted to boolean and then evaluated.
+     */
+    public function valid()
+    {
+        return $this->storage->valid();
+    }
+
+    /**
+     * (PHP 5 >= 5.1.0)
+     * Rewind the Iterator to the first element
+     *
+     * @link http://php.net/manual/en/iterator.rewind.php
+     */
+    public function rewind()
+    {
+        $this->storage->rewind();
+    }
+
+    /**
+     * (PHP 5 >= 5.1.0)
+     * String representation of object
+     *
+     * @link http://php.net/manual/en/serializable.serialize.php
+     * @return string the string representation of the object or &null;
+     */
+    public function serialize()
+    {
+        $data = [
+            'uid' => $this->getIdentifier()
+        ];
+        return serialize($data);
+    }
+
+    /**
+     * (PHP 5 >= 5.1.0)
+     * Constructs the object
+     *
+     * @link http://php.net/manual/en/serializable.unserialize.php
+     * @param string $serialized The string representation of the object
+     * @return mixed the original value unserialized.
+     */
+    public function unserialize($serialized)
+    {
+        $data = unserialize($serialized);
+        return self::load($data['uid']);
+    }
+
+    /**
+     * (PHP 5 >= 5.1.0)
+     * Count elements of an object
+     *
+     * @link http://php.net/manual/en/countable.count.php
+     * @return int The custom count as an integer.
+     */
+    public function count()
+    {
+        return $this->storage->count();
+    }
+
+    /**
+     * Getter for the title
+     *
+     * @return string
+     */
+    public function getTitle()
+    {
+        return $this->title;
+    }
+
+    /**
+     * Getter for the UID
+     *
+     * @return int
+     */
+    public function getUid()
+    {
+        return $this->uid;
+    }
+
+    /**
+     * Getter for the description
+     *
+     * @return string
+     */
+    public function getDescription()
+    {
+        return $this->description;
+    }
+
+    /**
+     * Setter for the title
+     *
+     * @param string $title
+     */
+    public function setTitle($title)
+    {
+        $this->title = $title;
+    }
+
+    /**
+     * Setter for the description
+     *
+     * @param string $desc
+     */
+    public function setDescription($desc)
+    {
+        $this->description = $desc;
+    }
+
+    /**
+     * Setter for the name of the data-source table
+     *
+     * @return string
+     */
+    public function getItemTableName()
+    {
+        return $this->itemTableName;
+    }
+
+    /**
+     * Setter for the name of the data-source table
+     *
+     * @param string $tableName
+     */
+    public function setItemTableName($tableName)
+    {
+        $this->itemTableName = $tableName;
+    }
+
+    /**
+     * Sorts collection via given callBackFunction
+     *
+     * The comparison function given as must return an integer less than, equal to, or greater than
+     * zero if the first argument is considered to be respectively less than, equal to, or greater than the second.
+     *
+     * @param $callbackFunction
+     * @see http://www.php.net/manual/en/function.usort.php
+     */
+    public function usort($callbackFunction)
+    {
+        // @todo Implement usort() method with TCEforms in mind
+        throw new \RuntimeException('This method is not yet supported.', 1322545589);
+    }
+
+    /**
+     * Moves the item within the collection
+     *
+     * the item at $currentPosition will be moved to
+     * $newPosition. Omitting $newPosition will move to top.
+     *
+     * @param int $currentPosition
+     * @param int $newPosition
+     */
+    public function moveItemAt($currentPosition, $newPosition = 0)
+    {
+        // @todo Implement usort() method with TCEforms in mind
+        throw new \RuntimeException('This method is not yet supported.', 1322545626);
+    }
+
+    /**
+     * Returns the uid of the collection
+     *
+     * @return int
+     */
+    public function getIdentifier()
+    {
+        return $this->uid;
+    }
+
+    /**
+     * Sets the identifier of the collection
+     *
+     * @param int $id
+     */
+    public function setIdentifier($id)
+    {
+        $this->uid = (int)$id;
+    }
+
+    /**
+     * Loads the collections with the given id from persistence
+     *
+     * For memory reasons, per default only f.e. title, database-table,
+     * identifier (what ever static data is defined) is loaded.
+     * Entries can be load on first access.
+     *
+     * @param int $id Id of database record to be loaded
+     * @param bool $fillItems Populates the entries directly on load, might be bad for memory on large collections
+     * @return \TYPO3\CMS\Core\Collection\CollectionInterface
+     */
+    public static function load($id, $fillItems = false)
+    {
+        $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)->getQueryBuilderForTable(static::$storageTableName);
+        $queryBuilder->getRestrictions()->removeAll()->add(GeneralUtility::makeInstance(DeletedRestriction::class));
+        $collectionRecord = $queryBuilder->select('*')
+            ->from(static::$storageTableName)
+            ->where($queryBuilder->expr()->eq('uid', $queryBuilder->createNamedParameter($id, \PDO::PARAM_INT)))
+            ->execute()
+            ->fetch();
+        return self::create($collectionRecord, $fillItems);
+    }
+
+    /**
+     * Creates a new collection objects and reconstitutes the
+     * given database record to the new object.
+     *
+     * @param array $collectionRecord Database record
+     * @param bool $fillItems Populates the entries directly on load, might be bad for memory on large collections
+     * @return \TYPO3\CMS\Core\Collection\CollectionInterface
+     */
+    public static function create(array $collectionRecord, $fillItems = false)
+    {
+        $collection = new static();
+        $collection->fromArray($collectionRecord);
+        if ($fillItems) {
+            $collection->loadContents();
+        }
+        return $collection;
+    }
+
+    /**
+     * Persists current collection state to underlying storage
+     */
+    public function persist()
+    {
+        $uid = $this->getIdentifier() == 0 ? 'NEW' . rand(100000, 999999) : $this->getIdentifier();
+        $data = [
+            trim(static::$storageTableName) => [
+                $uid => $this->getPersistableDataArray()
+            ]
+        ];
+        // New records always must have a pid
+        if ($this->getIdentifier() == 0) {
+            $data[trim(static::$storageTableName)][$uid]['pid'] = 0;
+        }
+        /** @var \TYPO3\CMS\Core\DataHandling\DataHandler $tce */
+        $tce = \TYPO3\CMS\Core\Utility\GeneralUtility::makeInstance(\TYPO3\CMS\Core\DataHandling\DataHandler::class);
+        $tce->start($data, []);
+        $tce->process_datamap();
+    }
+
+    /**
+     * Returns an array of the persistable properties and contents
+     * which are processable by DataHandler.
+     *
+     * For internal usage in persist only.
+     *
+     * @return array
+     */
+    abstract protected function getPersistableDataArray();
+
+    /**
+     * Generates comma-separated list of entry uids for usage in DataHandler
+     *
+     * also allow to add table name, if it might be needed by DataHandler for
+     * storing the relation
+     *
+     * @param bool $includeTableName
+     * @return string
+     */
+    protected function getItemUidList($includeTableName = true)
+    {
+        $list = [];
+        foreach ($this->storage as $entry) {
+            $list[] = ($includeTableName ? $this->getItemTableName() . '_' : '') . $entry['uid'];
+        }
+        return implode(',', $list);
+    }
+
+    /**
+     * Builds an array representation of this collection
+     *
+     * @return array
+     */
+    public function toArray()
+    {
+        $itemArray = [];
+        foreach ($this->storage as $item) {
+            $itemArray[] = $item;
+        }
+        return [
+            'uid' => $this->getIdentifier(),
+            'title' => $this->getTitle(),
+            'description' => $this->getDescription(),
+            'table_name' => $this->getItemTableName(),
+            'items' => $itemArray
+        ];
+    }
+
+    /**
+     * Loads the properties of this collection from an array
+     *
+     * @param array $array
+     */
+    public function fromArray(array $array)
+    {
+        $this->uid = $array['uid'];
+        $this->title = $array['title'];
+        $this->description = $array['description'];
+        $this->itemTableName = $array['table_name'];
+    }
+}

typo3/sysext/core/Classes/Collection/CollectionInterface.php

@@ -0,0 +1,27 @@
+<?php
+namespace TYPO3\CMS\Core\Collection;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * Marker interface for collection classes
+ *
+ * Collections are containers-classes handling the storage
+ * of data values (f.e. strings, records, relations) in a
+ * common and generic way, while the class manages the storage
+ * in an appropriate way itself
+ */
+interface CollectionInterface extends \Iterator, \Serializable, \Countable
+{
+}

typo3/sysext/core/Classes/Collection/EditableCollectionInterface.php

@@ -0,0 +1,51 @@
+<?php
+namespace TYPO3\CMS\Core\Collection;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * Interface for collection classes which es enabled to be modified
+ */
+interface EditableCollectionInterface
+{
+    /**
+     * Adds on entry to the collection
+     *
+     * @param mixed $data
+     */
+    public function add($data);
+
+    /**
+     * Adds a set of entries to the collection
+     *
+     * @param CollectionInterface $other
+     */
+    public function addAll(CollectionInterface $other);
+
+    /**
+     * Remove the given entry from collection
+     *
+     * Note: not the given "index"
+     *
+     * @param mixed $data
+     */
+    public function remove($data);
+
+    /**
+     * Removes all entries from the collection
+     *
+     * collection will be empty afterwards
+     */
+    public function removeAll();
+}

typo3/sysext/core/Classes/Collection/NameableCollectionInterface.php

@@ -0,0 +1,52 @@
+<?php
+namespace TYPO3\CMS\Core\Collection;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * Marker interface for a collection class with title and description
+ *
+ * Collections might be used internally as well as being shown
+ * With the nameable interface a title and a description are added
+ * to an collection, allowing every collection implementing Nameable
+ * being display by the same logic.
+ */
+interface NameableCollectionInterface
+{
+    /**
+     * Setter for the title
+     *
+     * @param string $title
+     */
+    public function setTitle($title);
+
+    /**
+     * Setter for the description
+     *
+     * @param string $description
+     */
+    public function setDescription($description);
+
+    /**
+     * Getter for the title
+     *
+     * @return string
+     */
+    public function getTitle();
+
+    /**
+     * Getter for the description
+     */
+    public function getDescription();
+}

typo3/sysext/core/Classes/Collection/PersistableCollectionInterface.php

@@ -0,0 +1,74 @@
+<?php
+namespace TYPO3\CMS\Core\Collection;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * Interface for collection class being persistable
+ *
+ * Collections are containers-classes handling the storage
+ * of data values (f.e. strings, records, relations) in a
+ * common and generic way, while the class manages the storage
+ * in an appropriate way itself
+ */
+interface PersistableCollectionInterface
+{
+    /**
+     * Get the identifier of the collection
+     *
+     * For database stored collections, this will be an integer,
+     * session stored, registry stored or other collections might
+     * use a string as well
+     *
+     * @return int|string
+     */
+    public function getIdentifier();
+
+    /**
+     * Sets the identifier of the collection
+     *
+     * @param int|string $id
+     */
+    public function setIdentifier($id);
+
+    /**
+     * Loads the collections with the given id from persistence
+     *
+     * For memory reasons, per default only f.e. title, database-table,
+     * identifier (what ever static data is defined) is loaded.
+     * Entries can be load on first access.
+     *
+     * @param int|string $id
+     * @param bool $fillItems Populates the entries directly on load, might be bad for memory on large collections
+     * @return \TYPO3\CMS\Core\Collection\CollectionInterface
+     */
+    public static function load($id, $fillItems = false);
+
+    /**
+     * Persists current collection state to underlying storage
+     */
+    public function persist();
+
+    /**
+     * Populates the content-entries of the storage
+     *
+     * Queries the underlying storage for entries of the collection
+     * and adds them to the collection data.
+     *
+     * If the content entries of the storage had not been loaded on creation
+     * ($fillItems = false) this function is to be used for loading the contents
+     * afterwards.
+     */
+    public function loadContents();
+}

typo3/sysext/core/Classes/Collection/RecordCollectionInterface.php

@@ -0,0 +1,35 @@
+<?php
+namespace TYPO3\CMS\Core\Collection;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * Collection for handling records from a single database-table.
+ */
+interface RecordCollectionInterface extends \TYPO3\CMS\Core\Collection\CollectionInterface, \TYPO3\CMS\Core\Collection\NameableCollectionInterface
+{
+    /**
+     * Setter for the name of the data-source table
+     *
+     * @param string $tableName
+     */
+    public function setItemTableName($tableName);
+
+    /**
+     * Setter for the name of the data-source table
+     *
+     * @return string
+     */
+    public function getItemTableName();
+}

typo3/sysext/core/Classes/Collection/RecordCollectionRepository.php

@@ -0,0 +1,232 @@
+<?php
+namespace TYPO3\CMS\Core\Collection;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Database\ConnectionPool;
+use TYPO3\CMS\Core\Database\Query\Restriction\DeletedRestriction;
+use TYPO3\CMS\Core\Database\Query\Restriction\FrontendRestrictionContainer;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * Implements the repository for record collections.
+ */
+class RecordCollectionRepository
+{
+    /**
+     * @var string
+     */
+    const TYPE_Static = 'static';
+
+    /**
+     * Name of the table the collection records are stored to
+     *
+     * @var string
+     */
+    protected $table = 'sys_collection';
+
+    /**
+     * @var string
+     */
+    protected $typeField = 'type';
+
+    /**
+     * @var string
+     */
+    protected $tableField = 'table_name';
+
+    /**
+     * Finds a record collection by uid.
+     *
+     * @param int $uid The uid to be looked up
+     * @return \TYPO3\CMS\Core\Collection\AbstractRecordCollection|null
+     */
+    public function findByUid($uid)
+    {
+        $result = null;
+        $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)->getQueryBuilderForTable($this->table);
+
+        if ($this->getEnvironmentMode() === 'FE') {
+            $queryBuilder->setRestrictions(GeneralUtility::makeInstance(FrontendRestrictionContainer::class));
+        } else {
+            $queryBuilder->getRestrictions()
+                ->removeAll()
+                ->add(GeneralUtility::makeInstance(DeletedRestriction::class));
+        }
+
+        $data = $queryBuilder->select('*')
+            ->from($this->table)
+            ->where($queryBuilder->expr()->eq('uid', $queryBuilder->createNamedParameter($uid, \PDO::PARAM_INT)))
+            ->execute()
+            ->fetch();
+        if (is_array($data)) {
+            $result = $this->createDomainObject($data);
+        }
+        return $result;
+    }
+
+    /**
+     * Finds all record collections.
+     *
+     * @return \TYPO3\CMS\Core\Collection\AbstractRecordCollection[]|null
+     */
+    public function findAll()
+    {
+        return $this->queryMultipleRecords();
+    }
+
+    /**
+     * Finds record collections by table name.
+     *
+     * @param string $tableName Name of the table to be looked up
+     * @return \TYPO3\CMS\Core\Collection\AbstractRecordCollection[]
+     */
+    public function findByTableName($tableName)
+    {
+        $expressionBuilder = GeneralUtility::makeInstance(ConnectionPool::class)
+            ->getQueryBuilderForTable($tableName)
+            ->expr();
+
+        return $this->queryMultipleRecords([
+            $expressionBuilder->eq($this->tableField, $expressionBuilder->literal($tableName))
+        ]);
+    }
+
+    /**
+     * Finds record collection by type.
+     *
+     * @param string $type Type to be looked up
+     * @return \TYPO3\CMS\Core\Collection\AbstractRecordCollection[]|null
+     */
+    public function findByType($type)
+    {
+        $expressionBuilder = GeneralUtility::makeInstance(ConnectionPool::class)
+            ->getQueryBuilderForTable($this->table)
+            ->expr();
+
+        return $this->queryMultipleRecords([
+            $expressionBuilder->eq($this->typeField, $expressionBuilder->literal($type))
+        ]);
+    }
+
+    /**
+     * Finds record collections by type and table name.
+     *
+     * @param string $type Type to be looked up
+     * @param string $tableName Name of the table to be looked up
+     * @return \TYPO3\CMS\Core\Collection\AbstractRecordCollection[]|null
+     */
+    public function findByTypeAndTableName($type, $tableName)
+    {
+        $expressionBuilder = GeneralUtility::makeInstance(ConnectionPool::class)
+            ->getQueryBuilderForTable($this->table)
+            ->expr();
+
+        return $this->queryMultipleRecords([
+            $expressionBuilder->eq($this->typeField, $expressionBuilder->literal($type)),
+            $expressionBuilder->eq($this->tableField, $expressionBuilder->literal($tableName))
+        ]);
+    }
+
+    /**
+     * Deletes a record collection by uid.
+     *
+     * @param int $uid uid to be deleted
+     */
+    public function deleteByUid($uid)
+    {
+        GeneralUtility::makeInstance(ConnectionPool::class)
+            ->getConnectionForTable($this->table)
+            ->update(
+                $this->table,
+                ['deleted' => 1, 'tstamp' => (int)$GLOBALS['EXEC_TIME']],
+                ['uid' => (int)$uid]
+            );
+    }
+
+    /**
+     * Queries for multiple records for the given conditions.
+     *
+     * @param array $conditions Conditions concatenated with AND for query
+     * @return \TYPO3\CMS\Core\Collection\AbstractRecordCollection[]|null
+     */
+    protected function queryMultipleRecords(array $conditions = [])
+    {
+        $result = null;
+
+        $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)->getQueryBuilderForTable($this->table);
+        $queryBuilder->getRestrictions()
+            ->removeAll()
+            ->add(GeneralUtility::makeInstance(DeletedRestriction::class));
+
+        $queryBuilder->select('*')
+            ->from($this->table);
+
+        if (!empty($conditions)) {
+            $queryBuilder->where(...$conditions);
+        }
+
+        $data = $queryBuilder->execute()->fetchAll();
+        if (!empty($data)) {
+            $result = $this->createMultipleDomainObjects($data);
+        }
+
+        return $result;
+    }
+
+    /**
+     * Creates a record collection domain object.
+     *
+     * @param array $record Database record to be reconstituted
+     * @return \TYPO3\CMS\Core\Collection\AbstractRecordCollection
+     * @throws \RuntimeException
+     */
+    protected function createDomainObject(array $record)
+    {
+        switch ($record['type']) {
+            case self::TYPE_Static:
+                $collection = StaticRecordCollection::create($record);
+                break;
+            default:
+                throw new \RuntimeException('Unknown record collection type "' . $record['type'], 1328646798);
+        }
+        return $collection;
+    }
+
+    /**
+     * Creates multiple record collection domain objects.
+     *
+     * @param array $data Array of multiple database records to be reconstituted
+     * @return \TYPO3\CMS\Core\Collection\AbstractRecordCollection[]
+     */
+    protected function createMultipleDomainObjects(array $data)
+    {
+        $collections = [];
+        foreach ($data as $collection) {
+            $collections[] = $this->createDomainObject($collection);
+        }
+        return $collections;
+    }
+
+    /**
+     * Function to return the current TYPO3_MODE.
+     * This function can be mocked in unit tests to be able to test frontend behaviour.
+     *
+     * @return string
+     */
+    protected function getEnvironmentMode()
+    {
+        return TYPO3_MODE;
+    }
+}

typo3/sysext/core/Classes/Collection/SortableCollectionInterface.php

@@ -0,0 +1,49 @@
+<?php
+namespace TYPO3\CMS\Core\Collection;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * Interface for collection class being sortable
+ *
+ * This interface allows you to either define a callback implementing
+ * your own sorting method and explicitly move an item from one position
+ * to another.
+ *
+ * This assumes that entries are sortable and therefore an index can be assigned
+ */
+interface SortableCollectionInterface
+{
+    /**
+     * Sorts collection via given callBackFunction
+     *
+     * The comparison function given as must return an integer less than, equal to, or greater than
+     * zero if the first argument is considered to be respectively less than, equal to, or greater than the second.
+     *
+     * @param $callbackFunction
+     * @see http://www.php.net/manual/en/function.usort.php
+     */
+    public function usort($callbackFunction);
+
+    /**
+     * Moves the item within the collection
+     *
+     * The item at $currentPosition will be moved to
+     * $newPosition. Omitting $newPosition will move to top.
+     *
+     * @param int $currentPosition
+     * @param int $newPosition
+     */
+    public function moveItemAt($currentPosition, $newPosition = 0);
+}

typo3/sysext/core/Classes/Collection/StaticRecordCollection.php

@@ -0,0 +1,197 @@
+<?php
+namespace TYPO3\CMS\Core\Collection;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Database\ConnectionPool;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * Implementation of a RecordCollection for static TCA-Records
+ */
+class StaticRecordCollection extends AbstractRecordCollection implements EditableCollectionInterface
+{
+    /**
+     * Creates a new collection objects and reconstitutes the
+     * given database record to the new object.
+     *
+     * @param array $collectionRecord Database record
+     * @param bool $fillItems Populates the entries directly on load, might be bad for memory on large collections
+     * @return \TYPO3\CMS\Core\Collection\StaticRecordCollection
+     */
+    public static function create(array $collectionRecord, $fillItems = false)
+    {
+        /** @var StaticRecordCollection $collection */
+        $collection = GeneralUtility::makeInstance(
+            self::class,
+            $collectionRecord['table_name']
+        );
+        $collection->fromArray($collectionRecord);
+        if ($fillItems) {
+            $collection->loadContents();
+        }
+        return $collection;
+    }
+
+    /**
+     * Creates this object.
+     *
+     * @param string $tableName Name of the table to be working on
+     * @throws \RuntimeException
+     */
+    public function __construct($tableName = null)
+    {
+        parent::__construct();
+        if (!empty($tableName)) {
+            $this->setItemTableName($tableName);
+        } elseif (empty($this->itemTableName)) {
+            throw new \RuntimeException(\TYPO3\CMS\Core\Collection\StaticRecordCollection::class . ' needs a valid itemTableName.', 1330293778);
+        }
+    }
+
+    /**
+     * Populates the content-entries of the storage
+     *
+     * Queries the underlying storage for entries of the collection
+     * and adds them to the collection data.
+     *
+     * If the content entries of the storage had not been loaded on creation
+     * ($fillItems = false) this function is to be used for loading the contents
+     * afterwards.
+     */
+    public function loadContents()
+    {
+        $entries = $this->getCollectedRecords();
+        $this->removeAll();
+        foreach ($entries as $entry) {
+            $this->add($entry);
+        }
+    }
+
+    /**
+     * Returns an array of the persistable properties and contents
+     * which are processable by DataHandler.
+     *
+     * for internal usage in persist only.
+     *
+     * @return array
+     */
+    protected function getPersistableDataArray()
+    {
+        return [
+            'title' => $this->getTitle(),
+            'description' => $this->getDescription(),
+            'items' => $this->getItemUidList(true),
+            'type' => 'static',
+            'table_name' => $this->getItemTableName()
+        ];
+    }
+
+    /**
+     * Adds on entry to the collection
+     *
+     * @param mixed $data
+     */
+    public function add($data)
+    {
+        $this->storage->push($data);
+    }
+
+    /**
+     * Adds a set of entries to the collection
+     *
+     * @param CollectionInterface $other
+     */
+    public function addAll(CollectionInterface $other)
+    {
+        foreach ($other as $value) {
+            $this->add($value);
+        }
+    }
+
+    /**
+     * Removes the given entry from collection
+     *
+     * Note: not the given "index"
+     *
+     * @param mixed $data
+     */
+    public function remove($data)
+    {
+        $offset = 0;
+        foreach ($this->storage as $value) {
+            if ($value == $data) {
+                break;
+            }
+            $offset++;
+        }
+        $this->storage->offsetUnset($offset);
+    }
+
+    /**
+     * Removes all entries from the collection
+     *
+     * collection will be empty afterwards
+     */
+    public function removeAll()
+    {
+        $this->storage = new \SplDoublyLinkedList();
+    }
+
+    /**
+     * Gets the collected records in this collection, by
+     * looking up the MM relations of this record to the
+     * table name defined in the local field 'table_name'.
+     *
+     * @return array
+     */
+    protected function getCollectedRecords()
+    {
+        $queryBuilder = GeneralUtility::makeInstance(ConnectionPool::class)
+            ->getQueryBuilderForTable(self::$storageTableName);
+        $queryBuilder->getRestrictions()->removeAll();
+        $statement = $queryBuilder->select($this->getItemTableName() . '.*')
+            ->from(self::$storageTableName)
+            ->join(
+                self::$storageTableName,
+                'sys_collection_entries',
+                'sys_collection_entries',
+                $queryBuilder->expr()->eq(
+                    'sys_collection_entries.uid_local',
+                    $queryBuilder->quoteIdentifier(self::$storageTableName . '.uid')
+                )
+            )
+            ->join(
+                'sys_collection_entries',
+                $this->getItemTableName(),
+                $this->getItemTableName(),
+                $queryBuilder->expr()->eq(
+                    'sys_collection_entries.uid_foreign',
+                    $queryBuilder->quoteIdentifier($this->getItemTableName() . '.uid')
+                )
+            )
+            ->where(
+                $queryBuilder->expr()->eq(
+                    self::$storageTableName . '.uid',
+                    $queryBuilder->createNamedParameter($this->getIdentifier(), \PDO::PARAM_INT)
+                )
+            )
+            ->execute();
+        $relatedRecords = [];
+        while ($record = $statement->fetch()) {
+            $relatedRecords[] = $record;
+        }
+        return $relatedRecords;
+    }
+}

typo3/sysext/core/Classes/Command/DumpAutoloadCommand.php

@@ -0,0 +1,64 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Command;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\Console\Style\SymfonyStyle;
+use TYPO3\CMS\Core\Core\ClassLoadingInformation;
+use TYPO3\CMS\Core\Core\Environment;
+
+/**
+ * Command for dumping the class-loading information.
+ */
+class DumpAutoloadCommand extends Command
+{
+    /**
+     * Defines the allowed options for this command
+     */
+    protected function configure()
+    {
+        $this->setDescription('Updates class loading information in non-composer mode.');
+        $this->setHelp('This command is only needed during development. The extension manager takes care of creating or updating this info properly during extension (de-)activation.');
+        $this->setAliases([
+            'extensionmanager:extension:dumpclassloadinginformation',
+            'extension:dumpclassloadinginformation'
+        ]);
+    }
+
+    /**
+     * This command is not needed in composer mode.
+     *
+     * @inheritdoc
+     */
+    public function isEnabled()
+    {
+        return !Environment::isComposerMode();
+    }
+
+    /**
+     * Dumps the class loading information
+     *
+     * @inheritdoc
+     */
+    protected function execute(InputInterface $input, OutputInterface $output)
+    {
+        $io = new SymfonyStyle($input, $output);
+        ClassLoadingInformation::dumpClassLoadingInformation();
+        $io->success('Class loading information has been updated.');
+    }
+}

typo3/sysext/core/Classes/Command/ExtensionListCommand.php

@@ -0,0 +1,118 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Command;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Helper\Table;
+use Symfony\Component\Console\Helper\TableCell;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Input\InputOption;
+use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\Console\Style\SymfonyStyle;
+use TYPO3\CMS\Core\Package\PackageManager;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * Command for listing all extensions known to the system.
+ *
+ * If the command is called with the verbose option, also shows the description of the package.
+ */
+class ExtensionListCommand extends Command
+{
+    /**
+     * Defines the allowed options for this command
+     */
+    protected function configure()
+    {
+        $this
+            ->setDescription('Shows the list of extensions available to the system.')
+            ->addOption(
+                'all',
+                'a',
+                InputOption::VALUE_NONE,
+                'Also display currently inactive/uninstalled extensions.'
+            )
+            ->addOption(
+                'inactive',
+                'i',
+                InputOption::VALUE_NONE,
+                'Only show inactive/uninstalled extensions available for installation.'
+            );
+    }
+
+    /**
+     * Shows the list of all extensions
+     *
+     * @inheritdoc
+     */
+    protected function execute(InputInterface $input, OutputInterface $output)
+    {
+        $io = new SymfonyStyle($input, $output);
+        $packageManager = GeneralUtility::makeInstance(PackageManager::class);
+
+        $onlyShowInactiveExtensions = $input->getOption('inactive');
+        $showAlsoInactiveExtensions = $input->getOption('all');
+        if ($onlyShowInactiveExtensions) {
+            $packages = $packageManager->getAvailablePackages();
+            $io->title('All inactive/currently uninstalled extensions');
+        } elseif ($showAlsoInactiveExtensions) {
+            $packages = $packageManager->getAvailablePackages();
+            $io->title('All installed (= active) and available (= inactive/currently uninstalled) extensions');
+        } else {
+            $packages = $packageManager->getActivePackages();
+            $io->title('All installed (= active) extensions');
+        }
+
+        $table = new Table($output);
+        $table->setHeaders([
+            'Extension Key',
+            'Version',
+            'Type',
+            'Status',
+        ]);
+        $table->setColumnWidths([30, 10, 8, 6]);
+
+        $formatter = $this->getHelper('formatter');
+        foreach ($packages as $package) {
+            $isActivePackage = $packageManager->isPackageActive($package->getPackageKey());
+            // Do not show the package if it is active but we only want to see inactive packages
+            if ($onlyShowInactiveExtensions && $isActivePackage) {
+                continue;
+            }
+            if ($package->getValueFromComposerManifest('type') === 'typo3-cms-framework') {
+                $type = 'System';
+            } else {
+                $type = 'Local';
+            }
+
+            // Ensure that the inactive extensions are shown as well
+            if ($onlyShowInactiveExtensions || ($showAlsoInactiveExtensions && !$isActivePackage)) {
+                $status = '<comment>inactive</comment>';
+            } else {
+                $status = '<info>active</info>';
+            }
+
+            $table->addRow([$package->getPackageKey(), $package->getPackageMetaData()->getVersion(), $type, $status]);
+
+            // Also show the description of the extension, if verbose option is set
+            if ($output->isVerbose()) {
+                $description = (string)$package->getValueFromComposerManifest('description');
+                $table->addRow([new TableCell('    ' . $formatter->truncate($description, 80) . "\n\n", ['colspan' => 4])]);
+            }
+        }
+        $table->render();
+    }
+}

typo3/sysext/core/Classes/Command/SendEmailCommand.php

@@ -0,0 +1,91 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Command;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Input\InputOption;
+use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\Console\Style\SymfonyStyle;
+use TYPO3\CMS\Core\Mail\Mailer;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * Command for sending spooled messages.
+ *
+ * Inspired and partially taken from symfony's swiftmailer package.
+ *
+ * @link https://github.com/symfony/swiftmailer-bundle/blob/master/Command/SendEmailCommand.php
+ */
+class SendEmailCommand extends Command
+{
+    /**
+     * Defines the allowed options for this command
+     */
+    protected function configure()
+    {
+        $this
+            ->setDescription('Sends emails from the spool')
+            ->addOption('message-limit', null, InputOption::VALUE_REQUIRED, 'The maximum number of messages to send.')
+            ->addOption('time-limit', null, InputOption::VALUE_REQUIRED, 'The time limit for sending messages (in seconds).')
+            ->addOption('recover-timeout', null, InputOption::VALUE_REQUIRED, 'The timeout for recovering messages that have taken too long to send (in seconds).');
+    }
+
+    /**
+     * Executes the mailer command
+     *
+     * @param InputInterface $input
+     * @param OutputInterface $output
+     * @return int|void|null
+     */
+    protected function execute(InputInterface $input, OutputInterface $output)
+    {
+        $io = new SymfonyStyle($input, $output);
+
+        $mailer = $this->getMailer();
+
+        $transport = $mailer->getTransport();
+        if ($transport instanceof \Swift_Transport_SpoolTransport) {
+            $spool = $transport->getSpool();
+            if ($spool instanceof \Swift_ConfigurableSpool) {
+                $spool->setMessageLimit((int)$input->getOption('message-limit'));
+                $spool->setTimeLimit((int)$input->getOption('time-limit'));
+            }
+            if ($spool instanceof \Swift_FileSpool) {
+                $recoverTimeout = (int)$input->getOption('recover-timeout');
+                if ($recoverTimeout) {
+                    $spool->recover($recoverTimeout);
+                } else {
+                    $spool->recover();
+                }
+            }
+            $sent = $spool->flushQueue($mailer->getRealTransport());
+            $io->comment($sent . ' emails sent');
+        } else {
+            $io->error('The Mailer Transport is not set to "spool".');
+        }
+    }
+
+    /**
+     * Returns the TYPO3 mailer.
+     *
+     * @return Mailer
+     */
+    protected function getMailer(): Mailer
+    {
+        return GeneralUtility::makeInstance(Mailer::class);
+    }
+}

typo3/sysext/core/Classes/Command/SiteListCommand.php

@@ -0,0 +1,97 @@
+<?php
+declare(strict_types = 1);
+
+namespace TYPO3\CMS\Core\Command;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Helper\Table;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\Console\Style\SymfonyStyle;
+use TYPO3\CMS\Core\Site\SiteFinder;
+
+/**
+ * Command for listing all configured sites
+ */
+class SiteListCommand extends Command
+{
+    /**
+     * Defines the allowed options for this command
+     */
+    protected function configure()
+    {
+        $this->setDescription('Shows the list of sites available to the system.');
+    }
+
+    /**
+     * Shows a table with all configured sites
+     *
+     * @inheritdoc
+     */
+    protected function execute(InputInterface $input, OutputInterface $output)
+    {
+        $io = new SymfonyStyle($input, $output);
+        $siteFinder = new SiteFinder();
+        $sites = $siteFinder->getAllSites();
+
+        if (empty($sites)) {
+            $io->title('No sites configured');
+            $io->note('Configure new sites in the "Sites" module.');
+            return 0;
+        }
+
+        $io->title('All configured sites');
+        $table = new Table($output);
+        $table->setHeaders([
+            'Identifier',
+            'Root PID',
+            'Base URL',
+            'Language',
+            'Locale',
+            'Status',
+        ]);
+        foreach ($sites as $site) {
+            $baseUrls = [];
+            $languages = [];
+            $locales = [];
+            $status = [];
+            foreach ($site->getLanguages() as $language) {
+                $baseUrls[] = (string)$language->getBase();
+                $languages[] = sprintf(
+                    '%s (id:%d)',
+                    $language->getTitle(),
+                    $language->getLanguageId()
+                );
+                $locales[] = $language->getLocale();
+                $status[] = $language->isEnabled()
+                    ? '<fg=green>enabled</>'
+                    : '<fg=yellow>disabled</>';
+            }
+            $table->addRow(
+                [
+                    '<options=bold>' . $site->getIdentifier() . '</>',
+                    $site->getRootPageId(),
+                    implode("\n", $baseUrls),
+                    implode("\n", $languages),
+                    implode("\n", $locales),
+                    implode("\n", $status),
+                ]
+            );
+        }
+        $table->render();
+        return 0;
+    }
+}

typo3/sysext/core/Classes/Command/SiteShowCommand.php

@@ -0,0 +1,58 @@
+<?php
+declare(strict_types = 1);
+
+namespace TYPO3\CMS\Core\Command;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Input\InputArgument;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+use Symfony\Component\Console\Style\SymfonyStyle;
+use Symfony\Component\Yaml\Yaml;
+use TYPO3\CMS\Core\Site\SiteFinder;
+
+/**
+ * Command for showing the configuration of a site
+ */
+class SiteShowCommand extends Command
+{
+    /**
+     * Defines the allowed options for this command
+     */
+    protected function configure()
+    {
+        $this->setDescription('Shows the configuration of the specified site. Specify the identifier via "site:show <identifier>".')
+            ->addArgument(
+                'identifier',
+                InputArgument::REQUIRED,
+                'The identifier of the site'
+            );
+    }
+
+    /**
+     * Shows the configuration of a site
+     *
+     * @inheritdoc
+     */
+    protected function execute(InputInterface $input, OutputInterface $output)
+    {
+        $io = new SymfonyStyle($input, $output);
+        $siteFinder = new SiteFinder();
+        $site = $siteFinder->getSiteByIdentifier($input->getArgument('identifier'));
+        $io->title('Site configuration for ' . $input->getArgument('identifier'));
+        $io->block(Yaml::dump($site->getConfiguration(), 4));
+    }
+}

typo3/sysext/core/Classes/Compatibility/LoadedExtensionArrayElement.php

@@ -0,0 +1,219 @@
+<?php
+namespace TYPO3\CMS\Core\Compatibility;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Core\Environment;
+use TYPO3\CMS\Core\Package\PackageInterface;
+
+/**
+ * Class to simulate the "old" extension information array element
+ *
+ * @internal
+ */
+class LoadedExtensionArrayElement implements \IteratorAggregate, \ArrayAccess, \Serializable, \Countable
+{
+    /**
+     * @var PackageInterface Instance of package manager
+     */
+    protected $package;
+
+    /**
+     * @var array List of relevant extension files
+     */
+    protected $extensionFilesToCheckFor = [
+        'ext_localconf.php',
+        'ext_tables.php',
+        'ext_tables.sql',
+        'ext_tables_static+adt.sql',
+        'ext_typoscript_constants.typoscript',
+        'ext_typoscript_setup.typoscript',
+        'ext_typoscript_constants.txt',
+        'ext_typoscript_setup.txt'
+    ];
+
+    /**
+     * @var array Final extension information
+     */
+    protected $extensionInformation = [];
+
+    /**
+     * Constructor builds compatibility API
+     *
+     * @param PackageInterface $package
+     */
+    public function __construct(PackageInterface $package)
+    {
+        $this->package = $package;
+        $this->initializeBasicExtensionInformation();
+        $this->initializeExtensionFiles();
+        $this->initializeExtensionIcon();
+    }
+
+    /**
+     * Create main information
+     */
+    protected function initializeBasicExtensionInformation()
+    {
+        $pathSite = Environment::getPublicPath() . '/';
+        $pathSiteLength = strlen($pathSite);
+        $absolutePackagePath = $this->package->getPackagePath();
+        if (strpos($absolutePackagePath, $pathSite) === 0) {
+            $relativePackagePathToPathSite = substr($absolutePackagePath, $pathSiteLength);
+            $relativePackagePathToPathSiteSegments = explode('/', $relativePackagePathToPathSite);
+            $packageType = null;
+            // Determine if extension is installed locally, globally or system (in this order)
+            switch (implode('/', array_slice($relativePackagePathToPathSiteSegments, 0, 2))) {
+                case 'typo3conf/ext':
+                    $packageType = 'L';
+                    break;
+                case TYPO3_mainDir . 'ext':
+                    $packageType = 'G';
+                    break;
+                case TYPO3_mainDir . 'sysext':
+                    $packageType = 'S';
+                    break;
+                case 'typo3temp/var/tests/test_ext':
+                    $packageType = 'T';
+                    break;
+            }
+            if ($packageType !== null) {
+                $this->extensionInformation['type'] = $packageType;
+            }
+        }
+    }
+
+    /**
+     * Initialize extension icon
+     */
+    protected function initializeExtensionIcon()
+    {
+        $this->extensionInformation['ext_icon'] = \TYPO3\CMS\Core\Utility\ExtensionManagementUtility::getExtensionIcon($this->package->getPackagePath());
+    }
+
+    /**
+     * Register found files in extension array if extension was found
+     */
+    protected function initializeExtensionFiles()
+    {
+        foreach ($this->extensionFilesToCheckFor as $fileName) {
+            $absolutePathToFile = $this->package->getPackagePath() . $fileName;
+            if (@file_exists($absolutePathToFile)) {
+                $this->extensionInformation[$fileName] = $absolutePathToFile;
+            }
+        }
+    }
+
+    /**
+     * Retrieve an external iterator
+     *
+     * @link http://php.net/manual/en/iteratoraggregate.getiterator.php
+     * @return \Traversable An instance of an object implementing Iterator or Traversable
+     */
+    public function getIterator()
+    {
+        return new \ArrayIterator($this->extensionInformation);
+    }
+
+    /**
+     * Whether an offset exists
+     *
+     * @link http://php.net/manual/en/arrayaccess.offsetexists.php
+     * @param mixed $offset An offset to check for.
+     * @return bool TRUE on success or FALSE on failure.
+     */
+    public function offsetExists($offset)
+    {
+        return isset($this->extensionInformation[$offset]);
+    }
+
+    /**
+     * Offset to retrieve
+     *
+     * @link http://php.net/manual/en/arrayaccess.offsetget.php
+     * @param mixed $offset The offset to retrieve.
+     * @return mixed Can return all value types.
+     */
+    public function offsetGet($offset)
+    {
+        return $this->extensionInformation[$offset];
+    }
+
+    /**
+     * Offset to set
+     *
+     * @link http://php.net/manual/en/arrayaccess.offsetset.php
+     * @param mixed $offset The offset to assign the value to.
+     * @param mixed $value The value to set.
+     * @throws \InvalidArgumentException
+     */
+    public function offsetSet($offset, $value)
+    {
+        throw new \InvalidArgumentException('The array $GLOBALS[\'TYPO3_LOADED_EXT\'] may not be modified.', 1361915115);
+    }
+
+    /**
+     * Offset to unset
+     *
+     * @link http://php.net/manual/en/arrayaccess.offsetunset.php
+     * @param mixed $offset The offset to unset.
+     * @throws \InvalidArgumentException
+     */
+    public function offsetUnset($offset)
+    {
+        throw new \InvalidArgumentException('The array $GLOBALS[\'TYPO3_LOADED_EXT\'] may not be modified.', 1361915206);
+    }
+
+    /**
+     * String representation of object
+     *
+     * @link http://php.net/manual/en/serializable.serialize.php
+     * @return string the string representation of the object or null
+     */
+    public function serialize()
+    {
+        return serialize($this->extensionInformation);
+    }
+
+    /**
+     * Constructs the object
+     *
+     * @link http://php.net/manual/en/serializable.unserialize.php
+     * @param string $serialized The string representation of the object.
+     * @return mixed the original value unserialized.
+     */
+    public function unserialize($serialized)
+    {
+        $this->extensionInformation = unserialize($serialized);
+    }
+
+    /**
+     * Count elements of an object
+     *
+     * @link http://php.net/manual/en/countable.count.php
+     * @return int The custom count as an integer. The return value is cast to an integer.
+     */
+    public function count()
+    {
+        return count($this->extensionInformation);
+    }
+
+    /**
+     * @return array
+     */
+    public function toArray()
+    {
+        return iterator_to_array($this);
+    }
+}

typo3/sysext/core/Classes/Compatibility/LoadedExtensionsArray.php

@@ -0,0 +1,227 @@
+<?php
+namespace TYPO3\CMS\Core\Compatibility;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * Class to simulate the "old" extension information array
+ *
+ * @internal
+ */
+class LoadedExtensionsArray implements \Iterator, \ArrayAccess, \Serializable, \Countable
+{
+    /**
+     * @var \TYPO3\CMS\Core\Package\PackageManager Instance of package manager
+     */
+    protected $packageManager;
+
+    /**
+     * @var array Loaded element cache
+     */
+    protected $loadedExtensionArrayElementCache = [];
+
+    /**
+     * @var string Pointer to current position
+     */
+    protected $iteratorPosition;
+
+    /**
+     * @param \TYPO3\CMS\Core\Package\PackageManager $packageManager
+     */
+    public function __construct(\TYPO3\CMS\Core\Package\PackageManager $packageManager)
+    {
+        $this->packageManager = $packageManager;
+    }
+
+    /**
+     * Whether an offset exists
+     *
+     * @link http://php.net/manual/en/arrayaccess.offsetexists.php
+     * @param mixed $offset An offset to check for.
+     * @return bool TRUE on success or FALSE on failure.
+     */
+    public function offsetExists($offset)
+    {
+        return $this->packageManager->isPackageActive($offset);
+    }
+
+    /**
+     * Offset to retrieve
+     *
+     * @link http://php.net/manual/en/arrayaccess.offsetget.php
+     * @param mixed $offset The offset to retrieve.
+     * @return mixed Can return all value types.
+     */
+    public function offsetGet($offset)
+    {
+        // Pass it through the package manager, as it resolves package aliases
+        $package = $this->packageManager->getPackage($offset);
+        $packageKey = $package->getPackageKey();
+        if (!isset($this->loadedExtensionArrayElementCache[$packageKey])) {
+            $this->loadedExtensionArrayElementCache[$packageKey] = new LoadedExtensionArrayElement($package);
+        }
+        return $this->loadedExtensionArrayElementCache[$packageKey];
+    }
+
+    /**
+     * Offset to set
+     *
+     * @link http://php.net/manual/en/arrayaccess.offsetset.php
+     * @param mixed $offset The offset to assign the value to.
+     * @param mixed $value The value to set.
+     * @throws \InvalidArgumentException
+     */
+    public function offsetSet($offset, $value)
+    {
+        throw new \InvalidArgumentException('The array $GLOBALS[\'TYPO3_LOADED_EXT\'] may not be modified.', 1361915596);
+    }
+
+    /**
+     * Offset to unset
+     *
+     * @link http://php.net/manual/en/arrayaccess.offsetunset.php
+     * @param mixed $offset The offset to unset.
+     * @throws \InvalidArgumentException
+     */
+    public function offsetUnset($offset)
+    {
+        throw new \InvalidArgumentException('The array $GLOBALS[\'TYPO3_LOADED_EXT\'] may not be modified.', 1361915610);
+    }
+
+    /**
+     * String representation of object
+     *
+     * @link http://php.net/manual/en/serializable.serialize.php
+     * @return string the string representation of the object or null
+     */
+    public function serialize()
+    {
+        return serialize($this->loadedExtensionArrayElementCache);
+    }
+
+    /**
+     * Constructs the object
+     *
+     * @link http://php.net/manual/en/serializable.unserialize.php
+     * @param string $serialized The string representation of the object.
+     * @return mixed the original value unserialized.
+     */
+    public function unserialize($serialized)
+    {
+        $this->loadedExtensionArrayElementCache = unserialize($serialized);
+    }
+
+    /**
+     * Count elements of an object
+     *
+     * @link http://php.net/manual/en/countable.count.php
+     * @return int The custom count as an integer.
+     */
+    public function count()
+    {
+        return count($this->packageManager->getActivePackages());
+    }
+
+    /**
+     * Return the current element
+     *
+     * @link http://php.net/manual/en/iterator.current.php
+     * @return mixed Can return any type.
+     */
+    public function current()
+    {
+        return $this->offsetGet($this->iteratorPosition);
+    }
+
+    /**
+     * Move forward to next element
+     *
+     * @link http://php.net/manual/en/iterator.next.php
+     */
+    public function next()
+    {
+        $packageKeys = array_keys($this->packageManager->getActivePackages());
+        $position = array_search($this->iteratorPosition, $packageKeys);
+        if (isset($packageKeys[$position + 1])) {
+            $this->iteratorPosition = $packageKeys[$position + 1];
+        } else {
+            $this->iteratorPosition = null;
+        }
+    }
+
+    /**
+     * Return the key of the current element
+     *
+     * @link http://php.net/manual/en/iterator.key.php
+     * @return mixed scalar on success, or null on failure.
+     */
+    public function key()
+    {
+        return $this->iteratorPosition;
+    }
+
+    /**
+     * Checks if current position is valid
+     *
+     * @link http://php.net/manual/en/iterator.valid.php
+     * @return bool The return value will be casted to boolean and then evaluated. Returns true on success or false on failure.
+     */
+    public function valid()
+    {
+        return $this->offsetExists($this->iteratorPosition);
+    }
+
+    /**
+     * Rewind the Iterator to the first element
+     *
+     * @link http://php.net/manual/en/iterator.rewind.php
+     */
+    public function rewind()
+    {
+        $keys = array_keys($this->packageManager->getActivePackages());
+        $this->iteratorPosition = array_shift($keys);
+    }
+
+    /**
+     * Reset
+     */
+    public function reset()
+    {
+        $this->loadedExtensionArrayElementCache = [];
+        $this->rewind();
+    }
+
+    /**
+     * Whether package manager is set in class
+     *
+     * @return bool TRUE if package manager is set
+     */
+    public function hasPackageManager()
+    {
+        return $this->packageManager !== null;
+    }
+
+    /**
+     * @return array
+     */
+    public function toArray()
+    {
+        return array_map(
+            function ($loadedExtElement) {
+                return $loadedExtElement->toArray();
+            },
+            iterator_to_array($this)
+        );
+    }
+}

typo3/sysext/core/Classes/Compatibility/PseudoSiteTcaDisplayCondition.php

@@ -0,0 +1,90 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Compatibility;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Routing\SiteMatcher;
+use TYPO3\CMS\Core\Site\Entity\PseudoSite;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * A display condition that returns true if the page we are dealing
+ * with is in a page tree that is represented by a PseudoSite object.
+ *
+ * This is used to suppress the 'slug' field in pseudo site page trees
+ * when editing page records and to show the alias field.
+ *
+ * Both "Pseudo sites" and "alias" db field will bite the dust in TYPO3 v10.0,
+ * so this is a temporary display condition for v9 only and thus marked internal.
+ *
+ * @internal Implementation and class will probably vanish in TYPO3 v10.0 without further notice
+ */
+class PseudoSiteTcaDisplayCondition
+{
+    /**
+     * Takes the given page id of the record and verifies if the page has
+     * a pseudo site object or a site object attached.
+     *
+     * @param array $parameters
+     * @return bool
+     * @throws \InvalidArgumentException
+     */
+    public function isInPseudoSite(array $parameters): bool
+    {
+        if (!isset($parameters['conditionParameters'][0])
+            || $parameters['conditionParameters'][0] !== 'pages'
+            || !isset($parameters['conditionParameters'][1])
+            || (!in_array($parameters['conditionParameters'][1], ['true', 'false'], true))
+            || empty($parameters['record']['uid'])
+        ) {
+            // Validate arguments
+            throw new \InvalidArgumentException(
+                'Invalid arguments using isInPseudoSite display condition',
+                1535055415
+            );
+        }
+
+        // uid is set if we're editing an existing page
+        // This resolves to 0 if the page is 'new'
+        $defaultLanguagePageId = (int)($parameters['record']['t3ver_oid'] ?: $parameters['record']['uid']);
+        if (is_array($parameters['record']['l10n_parent'])
+            && (int)$parameters['record']['sys_language_uid'][0] > 0
+        ) {
+            // But if the page is a localized page, we take the l10n_parent as uid for the sitematcher
+            $defaultLanguagePageId = (int)$parameters['record']['l10n_parent'][0];
+        }
+        // If still 0, this is probably a 'new' page somewhere, so we take the pid
+        // For additional fun, pid can be -1*real-pid, if the new page is created "after" an existing page
+        // Also take care if a record is a localized one, so set the pid instead of the parent (language) record
+        if ($defaultLanguagePageId === 0
+            || (int)$parameters['record']['sys_language_uid'][0] > 0
+        ) {
+            $defaultLanguagePageId = abs((int)$parameters['record']['pid']);
+        }
+        // And if now still 0, this is a 'new' page below pid 0. This will resolve to a 'NullSite' object
+
+        // If not a Site or a NullSite object, it must be a PseudoSite. We show the slug for
+        // NullSites (new pages below root) to simplify the editing workflow a bit.
+        $site = GeneralUtility::makeInstance(SiteMatcher::class)->matchByPageId($defaultLanguagePageId);
+        $isInPseudoSite = ($site instanceof PseudoSite);
+
+        if ($parameters['conditionParameters'][1] === 'false') {
+            // Negate if requested
+            return !$isInPseudoSite;
+        }
+
+        return $isInPseudoSite;
+    }
+}

typo3/sysext/core/Classes/Compatibility/PublicMethodDeprecationTrait.php

@@ -0,0 +1,97 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Compatibility;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * Trait to support the logging of deprecation of public INSTANCE methods.
+ *
+ * This is useful due to the long list of PHP4 methods that have been set to
+ * public previously, which should be removed or moved to "protected" / "private".
+ *
+ * Usage:
+ *
+ * 1. Use this trait for the class with the method to change the visibility status or to be removed.
+ * 2. Add the class methods with deprecated public visibility to $deprecatedPublicMethods.
+ * 3. Set these methods to protected or private.
+ * 4. Add the phpDoc tag "@private" to the method so IDEs understand that.
+ *
+ * With the next major release remove the "@private" tag and remove the methods from
+ * $deprecatedPublicMethods. Remove the trait use after removing the last deprecation.
+ *
+ * Note:
+ *
+ * - Only use this trait in classes only that do not define their own magic __call() method.
+ * - Do not use this trait for static methods.
+ *
+ * Example usage:
+ *
+ *
+ * class MyControllerClass {
+ *     use PublicMethodDeprecationTrait;
+ *
+ *     /**
+ *       * List previously publicly accessible variables
+ *       * @var array
+ *       *...
+ *     private $deprecatedPublicMethods = [
+ *         'myMethod' => 'Using MyControllerClass::myMethod() is deprecated and will not be possible anymore in TYPO3 v10.0. Use MyControllerClass:myOtherMethod() instead.'
+ *     ];
+ *
+ *     /**
+ *      * This is my method.
+ *      *
+ *      * @deprecated (if deprecated)
+ *      * @private (if switched to private)
+ *      /
+ *     protected function myMethod($arg1, $arg2);
+ * }
+ */
+
+/**
+ * This trait has no public methods by default, ensure to add a $deprecatedPublicMethods property
+ * to your class when using this trait.
+ */
+trait PublicMethodDeprecationTrait
+{
+    /**
+     * Checks if the method of the given name is available, calls it but throws a deprecation.
+     * If the method does not exist, a fatal error is thrown.
+     *
+     * Unavailable protected methods must return in a fatal error as usual.
+     * Marked methods are called and a deprecation entry is thrown.
+     *
+     * __call() is not called for public methods.
+     *
+     * @property array $deprecatedPublicMethods List of deprecated public methods
+     * @param string $methodName
+     * @param array $arguments
+     * @return mixed
+     */
+    public function __call(string $methodName, array $arguments)
+    {
+        if (method_exists($this, $methodName) && isset($this->deprecatedPublicMethods[$methodName])) {
+            trigger_error($this->deprecatedPublicMethods[$methodName], E_USER_DEPRECATED);
+            return $this->$methodName(...$arguments);
+        }
+
+        // Do the same behaviour as calling $myObject->method();
+        if (method_exists($this, $methodName)) {
+            throw new \Error('Call to protected/private method ' . self::class . '::' . $methodName . '()');
+        }
+
+        throw new \Error('Call to undefined method ' . self::class . '::' . $methodName . '()');
+    }
+}

typo3/sysext/core/Classes/Compatibility/PublicPropertyDeprecationTrait.php

@@ -0,0 +1,140 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Compatibility;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * Trait to support the logging of deprecation of public properties.
+ *
+ * This is useful due to the long list of PHP4 properties have been set to
+ * public previously, which should be removed or moved to "protected" / "private".
+ *
+ * Usage:
+ *
+ * - Use this trait for the class with the properties to change the visibility status or to be removed.
+ * - Set internal class properties to protected.
+ * - Add the phpDoc tag "private" to the property (so IDEs understand that).
+ * - Remove this tag with the next major version.
+ * - Remove trait after last deprecation.
+ *
+ * Note:
+ *
+ * Use this trait for classes only that do not make use of magic accessors otherwise.
+ *
+ * Example usage:
+ *
+ *
+ * class MyControllerClass {
+ *     use PublicPropertyDeprecationTrait;
+ *
+ *     /**
+ *       * List previously publically accessible variables
+ *       * @var array
+ *       *...
+ *     private $deprecatedPublicProperties = [
+ *         'myProperty' => 'Using myProperty is deprecated and will not be possible anymore in TYPO3 v10.0. Use getMyProperty() instead.'
+ *     ];
+ *
+ *     /**
+ *      * This is my property.
+ *      *
+ *      * @var bool
+ *      * @deprecated (if deprecated)
+ *      * @private (if switched to private)
+ *      /
+ *     protected $myProperty = true;
+ * }
+ */
+
+/**
+ * This trait has no public properties by default, ensure to add a $deprecatedPublicProperties to your class
+ * when using this trait.
+ */
+trait PublicPropertyDeprecationTrait
+{
+    /**
+     * Checks if the property of the given name is set.
+     *
+     * Unmarked protected properties must return false as usual.
+     * Marked properties are evaluated by isset().
+     *
+     * This method is not called for public properties.
+     *
+     * @property array $deprecatedPublicProperties List of deprecated public properties
+     * @param string $propertyName
+     * @return bool
+     */
+    public function __isset(string $propertyName)
+    {
+        if (isset($this->deprecatedPublicProperties[$propertyName])) {
+            trigger_error($this->deprecatedPublicProperties[$propertyName], E_USER_DEPRECATED);
+            return isset($this->$propertyName);
+        }
+        return false;
+    }
+
+    /**
+     * Gets the value of the property of the given name if tagged.
+     *
+     * The evaluation is done in the assumption that this method is never
+     * reached for a public property.
+     *
+     * @property array $deprecatedPublicProperties List of deprecated public properties
+     * @param string $propertyName
+     * @return mixed
+     */
+    public function __get(string $propertyName)
+    {
+        if (isset($this->deprecatedPublicProperties[$propertyName])) {
+            trigger_error($this->deprecatedPublicProperties[$propertyName], E_USER_DEPRECATED);
+        }
+        return $this->$propertyName;
+    }
+
+    /**
+     * Sets the property of the given name if tagged.
+     *
+     * Additionally it's allowed to set unknown properties.
+     *
+     * The evaluation is done in the assumption that this method is never
+     * reached for a public property.
+     *
+     * @property array $deprecatedPublicProperties List of deprecated public properties
+     * @param string $propertyName
+     * @param mixed $propertyValue
+     */
+    public function __set(string $propertyName, $propertyValue)
+    {
+        // It's allowed to set an unknown property as public, the check is thus necessary
+        if (property_exists($this, $propertyName) && isset($this->deprecatedPublicProperties[$propertyName])) {
+            trigger_error($this->deprecatedPublicProperties[$propertyName], E_USER_DEPRECATED);
+        }
+        $this->$propertyName = $propertyValue;
+    }
+
+    /**
+     * Unsets the property of the given name if tagged.
+     *
+     * @property array $deprecatedPublicProperties List of deprecated public properties
+     * @param string $propertyName
+     */
+    public function __unset(string $propertyName)
+    {
+        if (isset($this->deprecatedPublicProperties[$propertyName])) {
+            trigger_error($this->deprecatedPublicProperties[$propertyName], E_USER_DEPRECATED);
+        }
+        unset($this->$propertyName);
+    }
+}

typo3/sysext/core/Classes/Composer/CliEntryPoint.php

@@ -0,0 +1,69 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Composer;
+
+/*
+ * This file is part of the TYPO3 project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use Composer\Script\Event;
+use Composer\Util\Filesystem as FilesystemUtility;
+use Symfony\Component\Filesystem\Filesystem;
+use TYPO3\CMS\Composer\Plugin\Config;
+use TYPO3\CMS\Composer\Plugin\Core\InstallerScript;
+
+class CliEntryPoint implements InstallerScript
+{
+    /**
+     * Absolute path to entry script source
+     *
+     * @var string
+     */
+    private $source;
+
+    /**
+     * The target file relative to the web directory
+     *
+     * @var string
+     */
+    private $target;
+
+    public function __construct(string $source, string $target)
+    {
+        $this->source = $source;
+        $this->target = $target;
+    }
+
+    public function run(Event $event): bool
+    {
+        $composer = $event->getComposer();
+        $filesystemUtility = new FilesystemUtility();
+        $filesystem = new Filesystem();
+        $pluginConfig = Config::load($composer);
+
+        $entryPointContent = file_get_contents($this->source);
+        $targetFile = $pluginConfig->get('root-dir') . '/' . $this->target;
+        $autoloadFile = $composer->getConfig()->get('vendor-dir') . '/autoload.php';
+
+        $entryPointContent = preg_replace(
+            '/__DIR__ . \'[^\']*\'/',
+            $filesystemUtility->findShortestPathCode($targetFile, $autoloadFile),
+            $entryPointContent
+        );
+
+        $filesystemUtility->ensureDirectoryExists(dirname($targetFile));
+        $filesystem->dumpFile($targetFile, $entryPointContent);
+        $filesystem->chmod($targetFile, 0755);
+
+        return $filesystem->exists($targetFile);
+    }
+}

typo3/sysext/core/Classes/Composer/InstallerScripts.php

@@ -0,0 +1,39 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Composer;
+
+/*
+ * This file is part of the TYPO3 project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use Composer\Script\Event;
+use TYPO3\CMS\Composer\Plugin\Core\InstallerScriptsRegistration;
+use TYPO3\CMS\Composer\Plugin\Core\ScriptDispatcher;
+
+/**
+ * Hook into Composer build to generate TYPO3 cli tool entry script
+ * @internal only used for TYPO3 internally for setting up the installation.
+ */
+class InstallerScripts implements InstallerScriptsRegistration
+{
+    /**
+     * @param Event $event
+     * @param ScriptDispatcher $scriptDispatcher
+     */
+    public static function register(Event $event, ScriptDispatcher $scriptDispatcher)
+    {
+        $source = dirname(__DIR__, 2) . '/Resources/Private/Php/cli.php';
+        $target = 'typo3/sysext/core/bin/typo3';
+
+        $scriptDispatcher->addInstallerScript(new CliEntryPoint($source, $target));
+    }
+}

typo3/sysext/core/Classes/Configuration/ConfigurationManager.php

@@ -0,0 +1,450 @@
+<?php
+namespace TYPO3\CMS\Core\Configuration;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Core\Environment;
+use TYPO3\CMS\Core\Crypto\Random;
+use TYPO3\CMS\Core\Service\OpcodeCacheService;
+use TYPO3\CMS\Core\Utility\ArrayUtility;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * Handle loading and writing of global and local (instance specific)
+ * configuration.
+ *
+ * This class handles the access to the files
+ * - EXT:core/Configuration/DefaultConfiguration.php (default TYPO3_CONF_VARS)
+ * - typo3conf/LocalConfiguration.php (overrides of TYPO3_CONF_VARS)
+ * - typo3conf/AdditionalConfiguration.php (optional additional local code blocks)
+ *
+ * IMPORTANT:
+ *   This class is intended for internal core use ONLY.
+ *   Extensions should usually use the resulting $GLOBALS['TYPO3_CONF_VARS'] array,
+ *   do not try to modify settings in LocalConfiguration.php with an extension.
+ * @internal
+ */
+class ConfigurationManager
+{
+    /**
+     * @var string Path to default TYPO3_CONF_VARS file, relative to the public web folder
+     */
+    protected $defaultConfigurationFile = 'core/Configuration/DefaultConfiguration.php';
+
+    /**
+     * @var string Path to description file for TYPO3_CONF_VARS, relative to the public web folder
+     */
+    protected $defaultConfigurationDescriptionFile = 'core/Configuration/DefaultConfigurationDescription.yaml';
+
+    /**
+     * @var string Path to local overload TYPO3_CONF_VARS file, relative to the public web folder
+     */
+    protected $localConfigurationFile = 'LocalConfiguration.php';
+
+    /**
+     * @var string Path to additional local file, relative to the public web folder
+     */
+    protected $additionalConfigurationFile = 'AdditionalConfiguration.php';
+
+    /**
+     * @var string Path to factory configuration file used during installation as LocalConfiguration boilerplate
+     */
+    protected $factoryConfigurationFile = 'core/Configuration/FactoryConfiguration.php';
+
+    /**
+     * @var string Path to possible additional factory configuration file delivered by packages
+     */
+    protected $additionalFactoryConfigurationFile = 'AdditionalFactoryConfiguration.php';
+
+    /**
+     * Writing to these configuration paths is always allowed,
+     * even if the requested sub path does not exist yet.
+     *
+     * @var array
+     */
+    protected $whiteListedLocalConfigurationPaths = [
+        'EXT/extConf',
+        'EXTCONF',
+        'DB',
+        'SYS/caching/cacheConfigurations',
+        'SYS/session',
+        'EXTENSIONS',
+    ];
+
+    /**
+     * Return default configuration array
+     *
+     * @return array
+     */
+    public function getDefaultConfiguration()
+    {
+        return require $this->getDefaultConfigurationFileLocation();
+    }
+
+    /**
+     * Get the file location of the default configuration file,
+     * currently the path and filename.
+     *
+     * @return string
+     * @internal
+     */
+    public function getDefaultConfigurationFileLocation()
+    {
+        return Environment::getFrameworkBasePath() . '/' . $this->defaultConfigurationFile;
+    }
+
+    /**
+     * Get the file location of the default configuration description file,
+     * currently the path and filename.
+     *
+     * @return string
+     * @internal
+     */
+    public function getDefaultConfigurationDescriptionFileLocation()
+    {
+        return Environment::getFrameworkBasePath() . '/' . $this->defaultConfigurationDescriptionFile;
+    }
+
+    /**
+     * Return local configuration array typo3conf/LocalConfiguration.php
+     *
+     * @return array Content array of local configuration file
+     */
+    public function getLocalConfiguration()
+    {
+        return require $this->getLocalConfigurationFileLocation();
+    }
+
+    /**
+     * Get the file location of the local configuration file,
+     * currently the path and filename.
+     *
+     * @return string
+     * @internal
+     */
+    public function getLocalConfigurationFileLocation()
+    {
+        return Environment::getLegacyConfigPath() . '/' . $this->localConfigurationFile;
+    }
+
+    /**
+     * Returns local configuration array merged with default configuration
+     *
+     * @return array
+     */
+    public function getMergedLocalConfiguration(): array
+    {
+        $localConfiguration = $this->getDefaultConfiguration();
+        ArrayUtility::mergeRecursiveWithOverrule($localConfiguration, $this->getLocalConfiguration());
+        return $localConfiguration;
+    }
+
+    /**
+     * Get the file location of the additional configuration file,
+     * currently the path and filename.
+     *
+     * @return string
+     * @internal
+     */
+    public function getAdditionalConfigurationFileLocation()
+    {
+        return Environment::getLegacyConfigPath() . '/' . $this->additionalConfigurationFile;
+    }
+
+    /**
+     * Get absolute file location of factory configuration file
+     *
+     * @return string
+     */
+    protected function getFactoryConfigurationFileLocation()
+    {
+        return Environment::getFrameworkBasePath() . '/' . $this->factoryConfigurationFile;
+    }
+
+    /**
+     * Get absolute file location of factory configuration file
+     *
+     * @return string
+     */
+    protected function getAdditionalFactoryConfigurationFileLocation()
+    {
+        return Environment::getLegacyConfigPath() . '/' . $this->additionalFactoryConfigurationFile;
+    }
+
+    /**
+     * Override local configuration with new values.
+     *
+     * @param array $configurationToMerge Override configuration array
+     */
+    public function updateLocalConfiguration(array $configurationToMerge)
+    {
+        $newLocalConfiguration = $this->getLocalConfiguration();
+        ArrayUtility::mergeRecursiveWithOverrule($newLocalConfiguration, $configurationToMerge);
+        $this->writeLocalConfiguration($newLocalConfiguration);
+    }
+
+    /**
+     * Get a value at given path from default configuration
+     *
+     * @param string $path Path to search for
+     * @return mixed Value at path
+     */
+    public function getDefaultConfigurationValueByPath($path)
+    {
+        return ArrayUtility::getValueByPath($this->getDefaultConfiguration(), $path);
+    }
+
+    /**
+     * Get a value at given path from local configuration
+     *
+     * @param string $path Path to search for
+     * @return mixed Value at path
+     */
+    public function getLocalConfigurationValueByPath($path)
+    {
+        return ArrayUtility::getValueByPath($this->getLocalConfiguration(), $path);
+    }
+
+    /**
+     * Get a value from configuration, this is default configuration
+     * merged with local configuration
+     *
+     * @param string $path Path to search for
+     * @return mixed
+     */
+    public function getConfigurationValueByPath($path)
+    {
+        $defaultConfiguration = $this->getDefaultConfiguration();
+        ArrayUtility::mergeRecursiveWithOverrule($defaultConfiguration, $this->getLocalConfiguration());
+        return ArrayUtility::getValueByPath($defaultConfiguration, $path);
+    }
+
+    /**
+     * Update a given path in local configuration to a new value.
+     *
+     * @param string $path Path to update
+     * @param mixed $value Value to set
+     * @return bool TRUE on success
+     */
+    public function setLocalConfigurationValueByPath($path, $value)
+    {
+        $result = false;
+        if ($this->isValidLocalConfigurationPath($path)) {
+            $localConfiguration = $this->getLocalConfiguration();
+            $localConfiguration = ArrayUtility::setValueByPath($localConfiguration, $path, $value);
+            $result = $this->writeLocalConfiguration($localConfiguration);
+        }
+        return $result;
+    }
+
+    /**
+     * Update / set a list of path and value pairs in local configuration file
+     *
+     * @param array $pairs Key is path, value is value to set
+     * @return bool TRUE on success
+     */
+    public function setLocalConfigurationValuesByPathValuePairs(array $pairs)
+    {
+        $localConfiguration = $this->getLocalConfiguration();
+        foreach ($pairs as $path => $value) {
+            if ($this->isValidLocalConfigurationPath($path)) {
+                $localConfiguration = ArrayUtility::setValueByPath($localConfiguration, $path, $value);
+            }
+        }
+        return $this->writeLocalConfiguration($localConfiguration);
+    }
+
+    /**
+     * Remove keys from LocalConfiguration
+     *
+     * @param array $keys Array with key paths to remove from LocalConfiguration
+     * @return bool TRUE if something was removed
+     */
+    public function removeLocalConfigurationKeysByPath(array $keys)
+    {
+        $result = false;
+        $localConfiguration = $this->getLocalConfiguration();
+        foreach ($keys as $path) {
+            // Remove key if path is within LocalConfiguration
+            if (ArrayUtility::isValidPath($localConfiguration, $path)) {
+                $result = true;
+                $localConfiguration = ArrayUtility::removeByPath($localConfiguration, $path);
+            }
+        }
+        if ($result) {
+            $this->writeLocalConfiguration($localConfiguration);
+        }
+        return $result;
+    }
+
+    /**
+     * Enables a certain feature and writes the option to LocalConfiguration.php
+     * Short-hand method
+     *
+     * @param string $featureName something like "InlineSvgImages"
+     * @return bool true on successful writing the setting
+     */
+    public function enableFeature(string $featureName): bool
+    {
+        return $this->setLocalConfigurationValueByPath('SYS/features/' . $featureName, true);
+    }
+
+    /**
+     * Disables a feature and writes the option to LocalConfiguration.php
+     * Short-hand method
+     *
+     * @param string $featureName something like "InlineSvgImages"
+     * @return bool true on successful writing the setting
+     */
+    public function disableFeature(string $featureName): bool
+    {
+        return $this->setLocalConfigurationValueByPath('SYS/features/' . $featureName, false);
+    }
+
+    /**
+     * Checks if the configuration can be written.
+     *
+     * @return bool
+     * @internal
+     */
+    public function canWriteConfiguration()
+    {
+        $fileLocation = $this->getLocalConfigurationFileLocation();
+        return @is_writable(file_exists($fileLocation) ? $fileLocation : Environment::getLegacyConfigPath() . '/');
+    }
+
+    /**
+     * Reads the configuration array and exports it to the global variable
+     *
+     * @internal
+     * @throws \UnexpectedValueException
+     */
+    public function exportConfiguration()
+    {
+        if (@is_file($this->getLocalConfigurationFileLocation())) {
+            $localConfiguration = $this->getLocalConfiguration();
+            if (is_array($localConfiguration)) {
+                $defaultConfiguration = $this->getDefaultConfiguration();
+                ArrayUtility::mergeRecursiveWithOverrule($defaultConfiguration, $localConfiguration);
+                $GLOBALS['TYPO3_CONF_VARS'] = $defaultConfiguration;
+            } else {
+                throw new \UnexpectedValueException('LocalConfiguration invalid.', 1349272276);
+            }
+        } else {
+            // No LocalConfiguration (yet), load DefaultConfiguration
+            $GLOBALS['TYPO3_CONF_VARS'] = $this->getDefaultConfiguration();
+        }
+
+        // Load AdditionalConfiguration
+        if (@is_file($this->getAdditionalConfigurationFileLocation())) {
+            require $this->getAdditionalConfigurationFileLocation();
+        }
+    }
+
+    /**
+     * Write local configuration array to typo3conf/LocalConfiguration.php
+     *
+     * @param array $configuration The local configuration to be written
+     * @throws \RuntimeException
+     * @return bool TRUE on success
+     * @internal
+     */
+    public function writeLocalConfiguration(array $configuration)
+    {
+        $localConfigurationFile = $this->getLocalConfigurationFileLocation();
+        if (!$this->canWriteConfiguration()) {
+            throw new \RuntimeException(
+                $localConfigurationFile . ' is not writable.',
+                1346323822
+            );
+        }
+        $configuration = ArrayUtility::sortByKeyRecursive($configuration);
+        $result = GeneralUtility::writeFile(
+            $localConfigurationFile,
+            "<?php\n" .
+                'return ' .
+                    ArrayUtility::arrayExport($configuration) .
+                ";\n",
+            true
+        );
+
+        GeneralUtility::makeInstance(OpcodeCacheService::class)->clearAllActive($localConfigurationFile);
+
+        return $result;
+    }
+
+    /**
+     * Write additional configuration array to typo3conf/AdditionalConfiguration.php
+     *
+     * @param array $additionalConfigurationLines The configuration lines to be written
+     * @throws \RuntimeException
+     * @return bool TRUE on success
+     * @internal
+     */
+    public function writeAdditionalConfiguration(array $additionalConfigurationLines)
+    {
+        return GeneralUtility::writeFile(
+            $this->getAdditionalConfigurationFileLocation(),
+            "<?php\n" . implode("\n", $additionalConfigurationLines) . "\n"
+        );
+    }
+
+    /**
+     * Uses FactoryConfiguration file and a possible AdditionalFactoryConfiguration
+     * file in typo3conf to create a basic LocalConfiguration.php. This is used
+     * by the install tool in an early step.
+     *
+     * @throws \RuntimeException
+     * @internal
+     */
+    public function createLocalConfigurationFromFactoryConfiguration()
+    {
+        if (file_exists($this->getLocalConfigurationFileLocation())) {
+            throw new \RuntimeException(
+                'LocalConfiguration.php exists already',
+                1364836026
+            );
+        }
+        $localConfigurationArray = require $this->getFactoryConfigurationFileLocation();
+        $additionalFactoryConfigurationFileLocation = $this->getAdditionalFactoryConfigurationFileLocation();
+        if (file_exists($additionalFactoryConfigurationFileLocation)) {
+            $additionalFactoryConfigurationArray = require $additionalFactoryConfigurationFileLocation;
+            ArrayUtility::mergeRecursiveWithOverrule(
+                $localConfigurationArray,
+                $additionalFactoryConfigurationArray
+            );
+        }
+        $randomKey = GeneralUtility::makeInstance(Random::class)->generateRandomHexString(96);
+        $localConfigurationArray['SYS']['encryptionKey'] = $randomKey;
+
+        $this->writeLocalConfiguration($localConfigurationArray);
+    }
+
+    /**
+     * Check if access / write to given path in local configuration is allowed.
+     *
+     * @param string $path Path to search for
+     * @return bool TRUE if access is allowed
+     */
+    protected function isValidLocalConfigurationPath($path)
+    {
+        // Early return for white listed paths
+        foreach ($this->whiteListedLocalConfigurationPaths as $whiteListedPath) {
+            if (GeneralUtility::isFirstPartOfStr($path, $whiteListedPath)) {
+                return true;
+            }
+        }
+        return ArrayUtility::isValidPath($this->getDefaultConfiguration(), $path);
+    }
+}

typo3/sysext/core/Classes/Configuration/Exception/ExtensionConfigurationExtensionNotConfiguredException.php

@@ -0,0 +1,27 @@
+<?php
+namespace TYPO3\CMS\Core\Configuration\Exception;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Exception;
+
+/**
+ * An exception thrown if ExtensionConfiguration->get() is called for
+ * an extension that has no configuration.
+ *
+ * @internal
+ */
+class ExtensionConfigurationExtensionNotConfiguredException extends Exception
+{
+}

typo3/sysext/core/Classes/Configuration/Exception/ExtensionConfigurationPathDoesNotExistException.php

@@ -0,0 +1,27 @@
+<?php
+namespace TYPO3\CMS\Core\Configuration\Exception;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Exception;
+
+/**
+ * An exception thrown if ExtensionConfiguration->get() is called with
+ * a path that does not exist within the extension configuration.
+ *
+ * @internal
+ */
+class ExtensionConfigurationPathDoesNotExistException extends Exception
+{
+}

typo3/sysext/core/Classes/Configuration/ExtensionConfiguration.php

@@ -0,0 +1,665 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Configuration;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Configuration\Exception\ExtensionConfigurationExtensionNotConfiguredException;
+use TYPO3\CMS\Core\Configuration\Exception\ExtensionConfigurationPathDoesNotExistException;
+use TYPO3\CMS\Core\Package\PackageManager;
+use TYPO3\CMS\Core\Utility\ArrayUtility;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * API to get() instance specific extension configuration options.
+ *
+ * Extension authors are encouraged to use this API - it is currently a simple
+ * wrapper to access TYPO3_CONF_VARS['EXTENSIONS'] but could later become something
+ * different in case core decides to store extension configuration elsewhere.
+ *
+ * Extension authors must not access TYPO3_CONF_VARS['EXTENSIONS'] on their own.
+ *
+ * Extension configurations are often 'feature flags' currently defined by
+ * ext_conf_template.txt files. The core (more specifically the install tool)
+ * takes care default values and overridden values are properly prepared upon
+ * loading or updating an extension.
+ *
+ * Note only ->get() is official API and other public methods are low level
+ * core internal API that is usually only used by extension manager and install tool.
+ */
+class ExtensionConfiguration
+{
+    /**
+     * TypoScript hierarchy being build.
+     * Used parsing ext_conf_template.txt
+     *
+     * @var array
+     */
+    protected $setup = [];
+
+    /**
+     * Raw data, the input string exploded by LF.
+     * Used parsing ext_conf_template.txt
+     *
+     * @var array
+     */
+    protected $raw;
+
+    /**
+     * Pointer to entry in raw data array.
+     * Used parsing ext_conf_template.txt
+     *
+     * @var int
+     */
+    protected $rawPointer = 0;
+
+    /**
+     * Holding the value of the last comment
+     * Used parsing ext_conf_template.txt
+     *
+     * @var string
+     */
+    protected $lastComment = '';
+
+    /**
+     * Internal flag to create a multi-line comment (one of those like /* ... * /)
+     * Used parsing ext_conf_template.txt
+     *
+     * @var bool
+     */
+    protected $commentSet = false;
+
+    /**
+     * Internally set, when in brace. Counter.
+     * Used parsing ext_conf_template.txt
+     *
+     * @var int
+     */
+    protected $inBrace = 0;
+
+    /**
+     * Get a single configuration value, a sub array or the whole configuration.
+     *
+     * Examples:
+     * // Simple and typical usage: Get a single config value, or an array if the key is a "TypoScript"
+     * // a-like sub-path in ext_conf_template.txt "foo.bar = defaultValue"
+     * ->get('myExtension', 'aConfigKey');
+     *
+     * // Get all current configuration values, always an array
+     * ->get('myExtension');
+     *
+     * // Get a nested config value if the path is a "TypoScript" a-like sub-path
+     * // in ext_conf_template.txt "topLevelKey.subLevelKey = defaultValue"
+     * ->get('myExtension', 'topLevelKey/subLevelKey')
+     *
+     * Notes:
+     * - If a configuration or configuration path of an extension is not found, the
+     *   code tries to synchronize configuration with ext_conf_template.txt first, only
+     *   if still not found, it will throw exceptions.
+     * - Return values are NOT type safe: A boolean false could be returned as string 0.
+     *   Cast accordingly.
+     * - This API throws exceptions if the path does not exist or the extension
+     *   configuration is not available. The install tool takes care any new
+     *   ext_conf_template.txt values are available TYPO3_CONF_VARS['EXTENSIONS'],
+     *   a thrown exception indicates a programming error on developer side
+     *   and should not be caught.
+     * - It is not checked if the extension in question is loaded at all,
+     *   it's just checked the extension configuration path exists.
+     * - Extensions should typically not get configuration of a different extension.
+     *
+     * @param string $extension Extension name
+     * @param string $path Configuration path - eg. "featureCategory/coolThingIsEnabled"
+     * @return mixed The value. Can be a sub array or a single value.
+     * @throws ExtensionConfigurationExtensionNotConfiguredException If ext configuration does no exist
+     * @throws ExtensionConfigurationPathDoesNotExistException If a requested extension path does not exist
+     */
+    public function get(string $extension, string $path = '')
+    {
+        $hasBeenSynchronized = false;
+        if (!isset($GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS'][$extension]) || !is_array($GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS'][$extension])) {
+            // This if() should not be hit at "casual" runtime, but only in early setup phases
+            $this->synchronizeExtConfTemplateWithLocalConfigurationOfAllExtensions();
+            $hasBeenSynchronized = true;
+            if (!isset($GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS'][$extension]) || !is_array($GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS'][$extension])) {
+                // If there is still no such entry, even after sync -> throw
+                throw new ExtensionConfigurationExtensionNotConfiguredException(
+                    'No extension configuration for extension ' . $extension . ' found. Either this extension'
+                    . ' has no extension configuration or the configuration is not up to date. Execute the'
+                    . ' install tool to update configuration.',
+                    1509654728
+                );
+            }
+        }
+        if (empty($path)) {
+            return $GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS'][$extension];
+        }
+        if (!ArrayUtility::isValidPath($GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS'], $extension . '/' . $path)) {
+            // This if() should not be hit at "casual" runtime, but only in early setup phases
+            if (!$hasBeenSynchronized) {
+                $this->synchronizeExtConfTemplateWithLocalConfigurationOfAllExtensions();
+            }
+            // If there is still no such entry, even after sync -> throw
+            if (!ArrayUtility::isValidPath($GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS'], $extension . '/' . $path)) {
+                throw new ExtensionConfigurationPathDoesNotExistException(
+                    'Path ' . $path . ' does not exist in extension configuration',
+                    1509977699
+                );
+            }
+        }
+        return ArrayUtility::getValueByPath($GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS'], $extension . '/' . $path);
+    }
+
+    /**
+     * Store a new or overwrite an existing configuration value.
+     *
+     * This is typically used by core internal low level tasks like the install
+     * tool but may become handy if an extension needs to update extension configuration
+     * on the fly for whatever reason.
+     *
+     * Examples:
+     * // Set a full extension configuration ($value could be a nested array, too)
+     * ->set('myExtension', ['aFeature' => 'true', 'aCustomClass' => 'css-foo'])
+     *
+     * // Unset a whole extension configuration
+     * ->set('myExtension')
+     *
+     * Notes:
+     * - Do NOT call this at arbitrary places during runtime (eg. NOT in ext_localconf.php or
+     *   similar). ->set() is not supposed to be called each request since it writes LocalConfiguration
+     *   each time. This API is however OK to be called from extension manager hooks.
+     * - Values are not type safe, if the install tool wrote them,
+     *   boolean true could become string 1 on ->get()
+     * - It is not possible to store 'null' as value, giving $value=null
+     *   or no value at all will unset the path
+     * - Setting a value and calling ->get() afterwards will still return the new value.
+     * - Warning on AdditionalConfiguration.php: If this file overwrites settings, it spoils the
+     *   ->set() call and values may not end up as expected.
+     *
+     * @param string $extension Extension name
+     * @param string $path Configuration path to set - eg. "featureCategory/coolThingIsEnabled"
+     * @param null $value The value. If null, unset the path
+     * @internal
+     */
+    public function set(string $extension, string $path = '', $value = null)
+    {
+        if (empty($extension)) {
+            throw new \RuntimeException('extension name must not be empty', 1509715852);
+        }
+        if (!empty($path)) {
+            // @todo: this functionality can be removed once EXT:bootstrap_package is adapted to the new API.
+            $extensionConfiguration = $this->get($extension);
+            $value = ArrayUtility::setValueByPath($extensionConfiguration, $path, $value);
+        }
+        $configurationManager = GeneralUtility::makeInstance(ConfigurationManager::class);
+        if ($value === null) {
+            // Remove whole extension config
+            $configurationManager->removeLocalConfigurationKeysByPath(['EXTENSIONS/' . $extension]);
+            if (isset($GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS'][$extension])) {
+                unset($GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS'][$extension]);
+            }
+        } else {
+            // Set full extension config
+            $configurationManager->setLocalConfigurationValueByPath('EXTENSIONS/' . $extension, $value);
+            $GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS'][$extension] = $value;
+        }
+
+        // After TYPO3_CONF_VARS['EXTENSIONS'] has been written, update legacy layer TYPO3_CONF_VARS['EXTENSIONS']['extConf']
+        // @deprecated since TYPO3 v9, will be removed in TYPO3 v10.0 with removal of old serialized 'extConf' layer
+        if (!empty($GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS'])) {
+            $extConfArray = [];
+            foreach ($GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS'] as $extensionName => $extensionConfig) {
+                $extConfArray[$extensionName] = serialize($this->addDotsToArrayKeysRecursiveForLegacyExtConf($extensionConfig));
+            }
+            $configurationManager->setLocalConfigurationValueByPath('EXT/extConf', $extConfArray);
+            $GLOBALS['TYPO3_CONF_VARS']['EXT']['extConf'] = $extConfArray;
+        }
+    }
+
+    /**
+     * Set new configuration of all extensions and reload TYPO3_CONF_VARS.
+     * This is a "do all" variant of set() for all extensions that prevents
+     * writing and loading LocalConfiguration many times.
+     *
+     * @param array $configuration Configuration of all extensions
+     * @internal
+     */
+    public function setAll(array $configuration)
+    {
+        $configurationManager = GeneralUtility::makeInstance(ConfigurationManager::class);
+        $configurationManager->setLocalConfigurationValueByPath('EXTENSIONS', $configuration);
+        $GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS'] = $configuration;
+
+        // After TYPO3_CONF_VARS['EXTENSIONS'] has been written, update legacy layer TYPO3_CONF_VARS['EXTENSIONS']['extConf']
+        // @deprecated since TYPO3 v9, will be removed in TYPO3 v10.0 with removal of old serialized 'extConf' layer
+        $extConfArray = [];
+        foreach ($configuration as $extensionName => $extensionConfig) {
+            $extConfArray[$extensionName] = serialize($this->addDotsToArrayKeysRecursiveForLegacyExtConf($extensionConfig));
+        }
+        $configurationManager->setLocalConfigurationValueByPath('EXT/extConf', $extConfArray);
+        $GLOBALS['TYPO3_CONF_VARS']['EXT']['extConf'] = $extConfArray;
+    }
+
+    /**
+     * If there are new config settings in ext_conf_template of an extension,
+     * they are found here and synchronized to LocalConfiguration['EXTENSIONS'].
+     *
+     * Used when entering the install tool, during installation and if calling ->get()
+     * with an extension or path that is not yet found in LocalConfiguration
+     *
+     * @internal
+     */
+    public function synchronizeExtConfTemplateWithLocalConfigurationOfAllExtensions()
+    {
+        $activePackages = GeneralUtility::makeInstance(PackageManager::class)->getActivePackages();
+        $fullConfiguration = [];
+        $currentLocalConfiguration = $GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS'] ?? [];
+        foreach ($activePackages as $package) {
+            if (!@is_file($package->getPackagePath() . 'ext_conf_template.txt')) {
+                continue;
+            }
+            $extensionKey = $package->getPackageKey();
+            $currentExtensionConfig = $currentLocalConfiguration[$extensionKey] ?? [];
+            $extConfTemplateConfiguration = $this->getExtConfTablesWithoutCommentsAsNestedArrayWithoutDots($extensionKey);
+            ArrayUtility::mergeRecursiveWithOverrule($extConfTemplateConfiguration, $currentExtensionConfig);
+            if (!empty($extConfTemplateConfiguration)) {
+                $fullConfiguration[$extensionKey] = $extConfTemplateConfiguration;
+            }
+        }
+        // Write new config if changed. Loose array comparison to not write if only array key order is different
+        if ($fullConfiguration != $currentLocalConfiguration) {
+            $this->setAll($fullConfiguration);
+        }
+    }
+
+    /**
+     * Read values from ext_conf_template, verify if they are in LocalConfiguration.php
+     * already and if not, add them.
+     *
+     * Used public by extension manager when updating extension
+     *
+     * @param string $extensionKey The extension to sync
+     * @internal
+     */
+    public function synchronizeExtConfTemplateWithLocalConfiguration(string $extensionKey)
+    {
+        $package = GeneralUtility::makeInstance(PackageManager::class)->getPackage($extensionKey);
+        if (!@is_file($package->getPackagePath() . 'ext_conf_template.txt')) {
+            return;
+        }
+        $currentLocalConfiguration = $GLOBALS['TYPO3_CONF_VARS']['EXTENSIONS'][$extensionKey] ?? [];
+        $extConfTemplateConfiguration = $this->getExtConfTablesWithoutCommentsAsNestedArrayWithoutDots($extensionKey);
+        ArrayUtility::mergeRecursiveWithOverrule($extConfTemplateConfiguration, $currentLocalConfiguration);
+        // Write new config if changed. Loose array comparison to not write if only array key order is different
+        if ($extConfTemplateConfiguration != $currentLocalConfiguration) {
+            $this->set($extensionKey, '', $extConfTemplateConfiguration);
+        }
+    }
+
+    /**
+     * The old EXT/extConf layer had '.' (dots) at the end of all nested array keys. This is created here
+     * to keep EXT/extConf format compatible with old not yet adapted extensions.
+     * But extensions may rely on ending dots if using legacy unserialize() on their extensions, too.
+     *
+     * A EXTENSIONS array like:
+     * TYPO3_CONF_VARS['EXTENSIONS']['someExtension'] => [
+     *      'someKey' => [
+     *          'someSubKey' => [
+     *              'someSubSubKey' => 'someValue',
+     *          ],
+     *      ],
+     * ]
+     * becomes (serialized) in old EXT/extConf (mind the dots and end of array keys for sub arrays):
+     * TYPO3_CONF_VARS['EXTENSIONS']['someExtension'] => [
+     *      'someKey.' => [
+     *          'someSubKey.' => [
+     *              'someSubSubKey' => 'someValue',
+     *          ],
+     *      ],
+     * ]
+     *
+     * @param array $extensionConfig
+     * @return array
+     * @deprecated since TYPO3 v9, will be removed in TYPO3 v10.0 with removal of old serialized 'extConf' layer
+     */
+    private function addDotsToArrayKeysRecursiveForLegacyExtConf(array $extensionConfig): array
+    {
+        $newArray = [];
+        foreach ($extensionConfig as $key => $value) {
+            if (is_array($value)) {
+                $newArray[$key . '.'] = $this->addDotsToArrayKeysRecursiveForLegacyExtConf($value);
+            } else {
+                $newArray[$key] = $value;
+            }
+        }
+        return $newArray;
+    }
+
+    /**
+     * Helper method of ext_conf_template.txt parsing.
+     *
+     * Poor man version of getDefaultConfigurationFromExtConfTemplateAsValuedArray() which ignores
+     * comments and returns ext_conf_template as array where nested keys have no dots.
+     *
+     * @param string $extensionKey
+     * @return array
+     */
+    protected function getExtConfTablesWithoutCommentsAsNestedArrayWithoutDots(string $extensionKey): array
+    {
+        $configuration = $this->getParsedExtConfTemplate($extensionKey);
+        return $this->removeCommentsAndDotsRecursive($configuration);
+    }
+
+    /**
+     * Trigger main ext_conf_template.txt parsing logic.
+     * Needs to be public as it is used by install tool ExtensionConfigurationService
+     * which adds the comment parsing on top for display of options in install tool.
+     *
+     * @param string $extensionKey
+     * @return array
+     * @internal
+     */
+    public function getParsedExtConfTemplate(string $extensionKey): array
+    {
+        $rawConfigurationString = $this->getDefaultConfigurationRawString($extensionKey);
+        $configuration = [];
+        if ((string)$rawConfigurationString !== '') {
+            $this->raw = explode(LF, $rawConfigurationString);
+            $this->rawPointer = 0;
+            $this->setup = [];
+            $this->parseSub($this->setup);
+            if ($this->inBrace) {
+                throw new \RuntimeException(
+                    'Line ' . ($this->rawPointer - 1) . ': The script is short of ' . $this->inBrace . ' end brace(s)',
+                    1507645349
+                );
+            }
+            $configuration = $this->setup;
+        }
+        return $configuration;
+    }
+
+    /**
+     * Helper method of ext_conf_template.txt parsing.
+     *
+     * Return content of an extensions ext_conf_template.txt file if
+     * the file exists, empty string if file does not exist.
+     *
+     * @param string $extensionKey Extension key
+     * @return string
+     */
+    protected function getDefaultConfigurationRawString(string $extensionKey): string
+    {
+        $rawString = '';
+        $extConfTemplateFileLocation = GeneralUtility::getFileAbsFileName(
+            'EXT:' . $extensionKey . '/ext_conf_template.txt'
+        );
+        if (file_exists($extConfTemplateFileLocation)) {
+            $rawString = file_get_contents($extConfTemplateFileLocation);
+        }
+        return $rawString;
+    }
+
+    /**
+     * Helper method of ext_conf_template.txt parsing.
+     *
+     * "Comments" from the "TypoScript" parser below are identified by two (!) dots at the end of array keys
+     * and all array keys have a single dot at the end, if they have sub arrays. This is cleaned here.
+     *
+     * Incoming array:
+     * [
+     *  'automaticInstallation' => '1',
+     *  'automaticInstallation..' => '# cat=basic/enabled; ...'
+     *  'FE.' => [
+     *      'enabled' = '1',
+     *      'enabled..' => '# cat=basic/enabled; ...'
+     *  ]
+     * ]
+     *
+     * Output array:
+     * [
+     *  'automaticInstallation' => '1',
+     *  'FE' => [
+     *      'enabled' => '1',
+     * ]
+     *
+     * @param array $config Incoming configuration
+     * @return array
+     */
+    protected function removeCommentsAndDotsRecursive(array $config): array
+    {
+        $cleanedConfig = [];
+        foreach ($config as $key => $value) {
+            if (substr($key, -2) === '..') {
+                continue;
+            }
+            if (substr($key, -1) === '.') {
+                $cleanedConfig[rtrim($key, '.')] = $this->removeCommentsAndDotsRecursive($value);
+            } else {
+                $cleanedConfig[$key] = $value;
+            }
+        }
+        return $cleanedConfig;
+    }
+
+    /**
+     * Helper method of ext_conf_template.txt parsing.
+     *
+     * Parsing the $this->raw TypoScript lines from pointer, $this->rawP
+     *
+     * @param array $setup Reference to the setup array in which to accumulate the values.
+     */
+    protected function parseSub(array &$setup)
+    {
+        while (isset($this->raw[$this->rawPointer])) {
+            $line = ltrim($this->raw[$this->rawPointer]);
+            $this->rawPointer++;
+            // Set comment flag?
+            if (strpos($line, '/*') === 0) {
+                $this->commentSet = 1;
+            }
+            if (!$this->commentSet && $line) {
+                if ($line[0] !== '}' && $line[0] !== '#' && $line[0] !== '/') {
+                    // If not brace-end or comment
+                    // Find object name string until we meet an operator
+                    $varL = strcspn($line, "\t" . ' {=<>(');
+                    // check for special ":=" operator
+                    if ($varL > 0 && substr($line, $varL - 1, 2) === ':=') {
+                        --$varL;
+                    }
+                    // also remove tabs after the object string name
+                    $objStrName = substr($line, 0, $varL);
+                    if ($objStrName !== '') {
+                        $r = [];
+                        if (preg_match('/[^[:alnum:]_\\\\\\.:-]/i', $objStrName, $r)) {
+                            throw new \RuntimeException(
+                                'Line ' . ($this->rawPointer - 1) . ': Object Name String, "' . htmlspecialchars($objStrName) . '" contains invalid character "' . $r[0] . '". Must be alphanumeric or one of: "_:-\\."',
+                                1507645381
+                            );
+                        }
+                        $line = ltrim(substr($line, $varL));
+                        if ($line === '') {
+                            throw new \RuntimeException(
+                                'Line ' . ($this->rawPointer - 1) . ': Object Name String, "' . htmlspecialchars($objStrName) . '" was not followed by any operator, =<>({',
+                                1507645417
+                            );
+                        }
+                        switch ($line[0]) {
+                            case '=':
+                                if (strpos($objStrName, '.') !== false) {
+                                    $value = [];
+                                    $value[0] = trim(substr($line, 1));
+                                    $this->setVal($objStrName, $setup, $value);
+                                } else {
+                                    $setup[$objStrName] = trim(substr($line, 1));
+                                    if ($this->lastComment) {
+                                        // Setting comment..
+                                        $setup[$objStrName . '..'] .= $this->lastComment;
+                                    }
+                                }
+                                break;
+                            case '{':
+                                $this->inBrace++;
+                                if (strpos($objStrName, '.') !== false) {
+                                    $this->rollParseSub($objStrName, $setup);
+                                } else {
+                                    if (!isset($setup[$objStrName . '.'])) {
+                                        $setup[$objStrName . '.'] = [];
+                                    }
+                                    $this->parseSub($setup[$objStrName . '.']);
+                                }
+                                break;
+                            default:
+                                throw new \RuntimeException(
+                                    'Line ' . ($this->rawPointer - 1) . ': Object Name String, "' . htmlspecialchars($objStrName) . '" was not followed by any operator, =<>({',
+                                    1507645445
+                                );
+                        }
+
+                        $this->lastComment = '';
+                    }
+                } elseif ($line[0] === '}') {
+                    $this->inBrace--;
+                    $this->lastComment = '';
+                    if ($this->inBrace < 0) {
+                        throw new \RuntimeException(
+                            'Line ' . ($this->rawPointer - 1) . ': An end brace is in excess.',
+                            1507645489
+                        );
+                    }
+                    break;
+                } else {
+                    $this->lastComment .= rtrim($line) . LF;
+                }
+            }
+            // Unset comment
+            if ($this->commentSet) {
+                if (strpos($line, '*/') === 0) {
+                    $this->commentSet = 0;
+                }
+            }
+        }
+    }
+
+    /**
+     * Helper method of ext_conf_template.txt parsing.
+     *
+     * Parsing of TypoScript keys inside a curly brace where the key is composite of at least two keys,
+     * thus having to recursively call itself to get the value.
+     *
+     * @param string $string The object sub-path, eg "thisprop.another_prot"
+     * @param array $setup The local setup array from the function calling this function
+     */
+    protected function rollParseSub($string, array &$setup)
+    {
+        if ((string)$string === '') {
+            return;
+        }
+        list($key, $remainingKey) = $this->parseNextKeySegment($string);
+        $key .= '.';
+        if (!isset($setup[$key])) {
+            $setup[$key] = [];
+        }
+        $remainingKey === ''
+            ? $this->parseSub($setup[$key])
+            : $this->rollParseSub($remainingKey, $setup[$key]);
+    }
+
+    /**
+     * Helper method of ext_conf_template.txt parsing.
+     *
+     * Setting a value/property of an object string in the setup array.
+     *
+     * @param string $string The object sub-path, eg "thisprop.another_prot
+     * @param array $setup The local setup array from the function calling this function.
+     * @param void
+     */
+    protected function setVal($string, array &$setup, $value)
+    {
+        if ((string)$string === '') {
+            return;
+        }
+
+        list($key, $remainingKey) = $this->parseNextKeySegment($string);
+        $subKey = $key . '.';
+        if ($remainingKey === '') {
+            if (isset($value[0])) {
+                $setup[$key] = $value[0];
+            }
+            if (isset($value[1])) {
+                $setup[$subKey] = $value[1];
+            }
+            if ($this->lastComment) {
+                $setup[$key . '..'] .= $this->lastComment;
+            }
+        } else {
+            if (!isset($setup[$subKey])) {
+                $setup[$subKey] = [];
+            }
+            $this->setVal($remainingKey, $setup[$subKey], $value);
+        }
+    }
+
+    /**
+     * Helper method of ext_conf_template.txt parsing.
+     *
+     * Determines the first key segment of a TypoScript key by searching for the first
+     * unescaped dot in the given key string.
+     *
+     * Since the escape characters are only needed to correctly determine the key
+     * segment any escape characters before the first unescaped dot are
+     * stripped from the key.
+     *
+     * @param string $key The key, possibly consisting of multiple key segments separated by unescaped dots
+     * @return array Array with key segment and remaining part of $key
+     */
+    protected function parseNextKeySegment($key): array
+    {
+        // if no dot is in the key, nothing to do
+        $dotPosition = strpos($key, '.');
+        if ($dotPosition === false) {
+            return [$key, ''];
+        }
+
+        if (strpos($key, '\\') !== false) {
+            // backslashes are in the key, so we do further parsing
+            while ($dotPosition !== false) {
+                if ($dotPosition > 0 && $key[$dotPosition - 1] !== '\\' || $dotPosition > 1 && $key[$dotPosition - 2] === '\\') {
+                    break;
+                }
+                // escaped dot found, continue
+                $dotPosition = strpos($key, '.', $dotPosition + 1);
+            }
+
+            if ($dotPosition === false) {
+                // no regular dot found
+                $keySegment = $key;
+                $remainingKey = '';
+            } else {
+                if ($dotPosition > 1 && $key[$dotPosition - 2] === '\\' && $key[$dotPosition - 1] === '\\') {
+                    $keySegment = substr($key, 0, $dotPosition - 1);
+                } else {
+                    $keySegment = substr($key, 0, $dotPosition);
+                }
+                $remainingKey = substr($key, $dotPosition + 1);
+            }
+
+            // fix key segment by removing escape sequences
+            $keySegment = str_replace('\\.', '.', $keySegment);
+        } else {
+            // no backslash in the key, we're fine off
+            list($keySegment, $remainingKey) = explode('.', $key, 2);
+        }
+        return [$keySegment, $remainingKey];
+    }
+}

typo3/sysext/core/Classes/Configuration/Features.php

@@ -0,0 +1,65 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Configuration;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * A lightweight API class to check if a feature is enabled.
+ *
+ * Features are simple options (true/false), and are stored in the
+ * global configuration array $TYPO3_CONF_VARS[SYS][features].
+ *
+ * For disabling or enabling a feature the "ConfigurationManager"
+ * should be used.
+ *
+ * -- Naming --
+ *
+ * Feature names should NEVER named "enable" or having a negation, or containing versions or years
+ *    "enableFeatureXyz"
+ *    "disableOverlays"
+ *    "schedulerRevamped"
+ *    "useDoctrineQueries"
+ *    "disablePreparedStatements"
+ *    "disableHooksInFE"
+ *
+ * Proper namings for features
+ *    "ExtendedRichtextFormat"
+ *    "NativeYamlParser"
+ *    "InlinePageTranslations"
+ *    "TypoScriptParserIncludesAsXml"
+ *    "NativeDoctrineQueries"
+ *
+ * Ideally, these feature switches are added via the Install Tool or via FactoryConfiguration
+ * and can be used for Extensions as well.
+ *
+ * --- Usage ---
+ *
+ * if (GeneralUtility::makeInstance(Features::class)->isFeatureEnabled('InlineSvg')) {
+ *   ... do stuff here ...
+ * }
+ */
+class Features
+{
+    /**
+     * Checks if a feature is active
+     *
+     * @param string $featureName the name of the feature
+     * @return bool
+     */
+    public function isFeatureEnabled(string $featureName): bool
+    {
+        return isset($GLOBALS['TYPO3_CONF_VARS']['SYS']['features'][$featureName]) && $GLOBALS['TYPO3_CONF_VARS']['SYS']['features'][$featureName] === true;
+    }
+}

typo3/sysext/core/Classes/Configuration/FlexForm/Exception/AbstractInvalidDataStructureException.php

@@ -0,0 +1,25 @@
+<?php
+namespace TYPO3\CMS\Core\Configuration\FlexForm\Exception;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Exception;
+
+/**
+ * Abstract exception thrown if data structures can not be resolved,
+ * found or parsed.
+ */
+abstract class AbstractInvalidDataStructureException extends Exception
+{
+}

typo3/sysext/core/Classes/Configuration/FlexForm/Exception/InvalidCombinedPointerFieldException.php

@@ -0,0 +1,22 @@
+<?php
+namespace TYPO3\CMS\Core\Configuration\FlexForm\Exception;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * Thrown if a combined ds_pointerField can not be resolved.
+ */
+class InvalidCombinedPointerFieldException extends AbstractInvalidDataStructureException
+{
+}

typo3/sysext/core/Classes/Configuration/FlexForm/Exception/InvalidIdentifierException.php

@@ -0,0 +1,22 @@
+<?php
+namespace TYPO3\CMS\Core\Configuration\FlexForm\Exception;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * Thrown if parseFlexFormDataStructureByIdentifier() is given an empty string
+ */
+class InvalidIdentifierException extends AbstractInvalidDataStructureException
+{
+}

typo3/sysext/core/Classes/Configuration/FlexForm/Exception/InvalidParentRowException.php

@@ -0,0 +1,23 @@
+<?php
+namespace TYPO3\CMS\Core\Configuration\FlexForm\Exception;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * Exception thrown if lookup of a parent row in a tree does not return a valid result
+ * during flex from structure lookup.
+ */
+class InvalidParentRowException extends AbstractInvalidDataStructureException
+{
+}

typo3/sysext/core/Classes/Configuration/FlexForm/Exception/InvalidParentRowLoopException.php

@@ -0,0 +1,22 @@
+<?php
+namespace TYPO3\CMS\Core\Configuration\FlexForm\Exception;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * Exception thrown if lookup of a parent row in a tree results in a loop.
+ */
+class InvalidParentRowLoopException extends AbstractInvalidDataStructureException
+{
+}

typo3/sysext/core/Classes/Configuration/FlexForm/Exception/InvalidParentRowRootException.php

@@ -0,0 +1,22 @@
+<?php
+namespace TYPO3\CMS\Core\Configuration\FlexForm\Exception;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * Exception thrown if lookup of a parent row in a tree is root node and still nothing was found.
+ */
+class InvalidParentRowRootException extends AbstractInvalidDataStructureException
+{
+}

typo3/sysext/core/Classes/Configuration/FlexForm/Exception/InvalidPointerFieldValueException.php

@@ -0,0 +1,22 @@
+<?php
+namespace TYPO3\CMS\Core\Configuration\FlexForm\Exception;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * Exception thrown if ds_pointerField does not point to a valid value.
+ */
+class InvalidPointerFieldValueException extends AbstractInvalidDataStructureException
+{
+}

typo3/sysext/core/Classes/Configuration/FlexForm/Exception/InvalidSinglePointerFieldException.php

@@ -0,0 +1,22 @@
+<?php
+namespace TYPO3\CMS\Core\Configuration\FlexForm\Exception;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * Thrown if a single ds_pointerField can not be resolved.
+ */
+class InvalidSinglePointerFieldException extends AbstractInvalidDataStructureException
+{
+}

typo3/sysext/core/Classes/Configuration/FlexForm/Exception/InvalidTcaException.php

@@ -0,0 +1,24 @@
+<?php
+namespace TYPO3\CMS\Core\Configuration\FlexForm\Exception;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * Thrown if TCA is invalid.
+ * This may happen if a record is opened that points to a data structure of
+ * a no longer loaded extension
+ */
+class InvalidTcaException extends AbstractInvalidDataStructureException
+{
+}

typo3/sysext/core/Classes/Configuration/Loader/Exception/YamlFileLoadingException.php

@@ -0,0 +1,21 @@
+<?php
+declare(strict_types = 1);
+
+namespace TYPO3\CMS\Core\Configuration\Loader\Exception;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+class YamlFileLoadingException extends \RuntimeException
+{
+}

typo3/sysext/core/Classes/Configuration/Loader/Exception/YamlParseException.php

@@ -0,0 +1,21 @@
+<?php
+declare(strict_types = 1);
+
+namespace TYPO3\CMS\Core\Configuration\Loader\Exception;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+class YamlParseException extends \RuntimeException
+{
+}

typo3/sysext/core/Classes/Configuration/Loader/YamlFileLoader.php

@@ -0,0 +1,251 @@
+<?php
+namespace TYPO3\CMS\Core\Configuration\Loader;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use Psr\Log\LoggerAwareInterface;
+use Psr\Log\LoggerAwareTrait;
+use Symfony\Component\Yaml\Yaml;
+use TYPO3\CMS\Core\Configuration\Loader\Exception\YamlFileLoadingException;
+use TYPO3\CMS\Core\Configuration\Loader\Exception\YamlParseException;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * A YAML file loader that allows to load YAML files, based on the Symfony/Yaml component
+ *
+ * In addition to just load a YAML file, it adds some special functionality.
+ *
+ * - A special "imports" key in the YAML file allows to include other YAML files recursively
+ *   where the actual YAML file gets loaded after the import statements, which are interpreted at the very beginning
+ *
+ * - Merging configuration options of import files when having simple "lists" will add items to the list instead
+ *   of overwriting them.
+ *
+ * - Special placeholder values set via %optionA.suboptionB% replace the value with the named path of the configuration
+ *   The placeholders will act as a full replacement of this value.
+ *
+ * - Environment placeholder values set via %env(option)% will be replaced by env variables of the same name
+ */
+class YamlFileLoader implements LoggerAwareInterface
+{
+    use LoggerAwareTrait;
+
+    public const PROCESS_PLACEHOLDERS = 1;
+    public const PROCESS_IMPORTS = 2;
+
+    /**
+     * Loads and parses a YAML file, and returns an array with the found data
+     *
+     * @param string $fileName either relative to TYPO3's base project folder or prefixed with EXT:...
+     * @param int $flags Flags to configure behaviour of the loader: see public PROCESS_ constants above
+     * @return array the configuration as array
+     */
+    public function load(string $fileName, int $flags = self::PROCESS_PLACEHOLDERS | self::PROCESS_IMPORTS): array
+    {
+        $content = $this->getFileContents($fileName);
+        $content = Yaml::parse($content);
+
+        if (!is_array($content)) {
+            throw new YamlParseException(
+                'YAML file "' . $fileName . '" could not be parsed into valid syntax, probably empty?',
+                1497332874
+            );
+        }
+
+        if (($flags & self::PROCESS_IMPORTS) === self::PROCESS_IMPORTS) {
+            $content = $this->processImports($content);
+        }
+        if (($flags & self::PROCESS_PLACEHOLDERS) === self::PROCESS_PLACEHOLDERS) {
+            // Check for "%" placeholders
+            $content = $this->processPlaceholders($content, $content);
+        }
+
+        return $content;
+    }
+
+    /**
+     * Put into a separate method to ease the pains with unit tests
+     *
+     * @param string $fileName either relative to TYPO3's base project folder or prefixed with EXT:...
+     *
+     * @return string the contents of the file
+     * @throws YamlFileLoadingException when the file was not accessible
+     */
+    protected function getFileContents(string $fileName): string
+    {
+        $streamlinedFileName = GeneralUtility::getFileAbsFileName($fileName);
+        if (!$streamlinedFileName) {
+            throw new YamlFileLoadingException('YAML File "' . $fileName . '" could not be loaded', 1485784246);
+        }
+        return file_get_contents($streamlinedFileName);
+    }
+
+    /**
+     * Return value from environment variable
+     *
+     * Environment variables may only contain word characters and underscores (a-zA-Z0-9_)
+     * to be compatible to shell environments.
+     *
+     * @param string $value
+     * @return string
+     */
+    protected function getValueFromEnv(string $value): string
+    {
+        $matches = [];
+        preg_match_all('/%env\([\'"]?(\w+)[\'"]?\)%/', $value, $matches);
+        $envVars = array_combine($matches[0], $matches[1]);
+        foreach ($envVars as $substring => $envVarName) {
+            $envVar = getenv($envVarName);
+            $value = $envVar ? str_replace($substring, $envVar, $value) : $value;
+        }
+        return $value;
+    }
+
+    /**
+     * Checks for the special "imports" key on the main level of a file,
+     * which calls "load" recursively.
+     * @param array $content
+     *
+     * @return array
+     */
+    protected function processImports(array $content): array
+    {
+        if (isset($content['imports']) && is_array($content['imports'])) {
+            foreach ($content['imports'] as $import) {
+                try {
+                    $importedContent = $this->load($import['resource']);
+                    // override the imported content with the one from the current file
+                    $content = $this->merge($importedContent, $content);
+                } catch (YamlParseException | YamlFileLoadingException $exception) {
+                    $this->logger->error($exception->getMessage(), ['exception' => $exception]);
+                }
+            }
+            unset($content['imports']);
+        }
+        return $content;
+    }
+
+    /**
+     * Main function that gets called recursively to check for %...% placeholders
+     * inside the array
+     *
+     * @param array $content the current sub-level content array
+     * @param array $referenceArray the global configuration array
+     *
+     * @return array the modified sub-level content array
+     */
+    protected function processPlaceholders(array $content, array $referenceArray): array
+    {
+        foreach ($content as $k => $v) {
+            if ($this->isEnvPlaceholder($v)) {
+                $content[$k] = $this->getValueFromEnv($v);
+            } elseif ($this->isPlaceholder($v)) {
+                $content[$k] = $this->getValueFromReferenceArray($v, $referenceArray);
+            } elseif (is_array($v)) {
+                $content[$k] = $this->processPlaceholders($v, $referenceArray);
+            }
+        }
+        return $content;
+    }
+
+    /**
+     * Returns the value for a placeholder as fetched from the referenceArray
+     *
+     * @param string $placeholder the string to search for
+     * @param array $referenceArray the main configuration array where to look up the data
+     *
+     * @return array|mixed|string
+     */
+    protected function getValueFromReferenceArray(string $placeholder, array $referenceArray)
+    {
+        $pointer = trim($placeholder, '%');
+        $parts = explode('.', $pointer);
+        $referenceData = $referenceArray;
+        foreach ($parts as $part) {
+            if (isset($referenceData[$part])) {
+                $referenceData = $referenceData[$part];
+            } else {
+                // return unsubstituted placeholder
+                return $placeholder;
+            }
+        }
+        if ($this->isPlaceholder($referenceData)) {
+            $referenceData = $this->getValueFromReferenceArray($referenceData, $referenceArray);
+        }
+        return $referenceData;
+    }
+
+    /**
+     * Checks if a value is a string and begins and ends with %...%
+     *
+     * @param mixed $value the probe to check for
+     * @return bool
+     */
+    protected function isPlaceholder($value): bool
+    {
+        return is_string($value) && strpos($value, '%') === 0 && substr($value, -1) === '%';
+    }
+
+    /**
+     * Checks if a value is a string and contains an env placeholder
+     *
+     * @param mixed $value the probe to check for
+     * @return bool
+     */
+    protected function isEnvPlaceholder($value): bool
+    {
+        return is_string($value) && (strpos($value, '%env(') !== false);
+    }
+
+    /**
+     * Same as array_replace_recursive except that when in simple arrays (= YAML lists), the entries are
+     * appended (array_merge)
+     *
+     * @param array $val1
+     * @param array $val2
+     *
+     * @return array
+     */
+    protected function merge(array $val1, array $val2): array
+    {
+        // Simple lists get merged / added up
+        if (count(array_filter(array_keys($val1), 'is_int')) === count($val1)) {
+            return array_merge($val1, $val2);
+        }
+        foreach ($val1 as $k => $v) {
+            // The key also exists in second array, if it is a simple value
+            // then $val2 will override the value, where an array is calling merge() recursively.
+            if (isset($val2[$k])) {
+                if (is_array($v) && isset($val2[$k])) {
+                    if (is_array($val2[$k])) {
+                        $val1[$k] = $this->merge($v, $val2[$k]);
+                    } else {
+                        $val1[$k] = $val2[$k];
+                    }
+                } else {
+                    $val1[$k] = $val2[$k];
+                }
+                unset($val2[$k]);
+            }
+        }
+        // If there are properties in the second array left, they are added up
+        if (!empty($val2)) {
+            foreach ($val2 as $k => $v) {
+                $val1[$k] = $v;
+            }
+        }
+
+        return $val1;
+    }
+}

typo3/sysext/core/Classes/Configuration/Richtext.php

@@ -0,0 +1,205 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Configuration;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Backend\Utility\BackendUtility;
+use TYPO3\CMS\Core\Configuration\Loader\YamlFileLoader;
+use TYPO3\CMS\Core\TypoScript\TypoScriptService;
+use TYPO3\CMS\Core\Utility\ArrayUtility;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * Prepare richtext configuration. Used in DataHandler and FormEngine
+ *
+ * @internal Internal class for the time being - may change / vanish any time
+ * @todo When I grow up, I want to become a data provider
+ */
+class Richtext
+{
+    /**
+     * This is an intermediate class / method to retrieve RTE
+     * configuration until all core places use data providers to do that.
+     *
+     * @param string $table The table the field is in
+     * @param string $field Field name
+     * @param int $pid Real page id
+     * @param string $recordType Record type value
+     * @param array $tcaFieldConf ['config'] section of TCA field
+     * @return array
+     */
+    public function getConfiguration(string $table, string $field, int $pid, string $recordType, array $tcaFieldConf): array
+    {
+        // create instance of NodeFactory, ask for "text" element
+        //
+        // As soon an the Data handler starts using FormDataProviders, this class can vanish again, and the hack to
+        // test for specific rich text instances can be dropped: Split the "TcaText" data provider into multiple parts, each
+        // RTE should register and own data provider that does the transformation / configuration providing. This way,
+        // the explicit check for different RTE classes is removed from core and "hooked in" by the RTE's.
+
+        // The main problem here is that all parameters that the processing needs is handed over to as TSconfig
+        // "dotted array" syntax. We convert at least the processing information available under "processing"
+        // together with pageTS, this way it can be overridden and understood in RteHtmlParser.
+        // However, all other parts of the core will depend on the non-dotted syntax (coming from YAML directly)
+
+        $pageTs = $this->getPageTsConfiguration($table, $field, $pid, $recordType);
+
+        // determine which preset to use
+        $usePreset = $pageTs['preset'] ?? $tcaFieldConf['richtextConfiguration'] ?? 'default';
+
+        // load configuration from preset
+        $configuration = $this->loadConfigurationFromPreset($usePreset);
+
+        // overlay preset configuration with pageTs
+        ArrayUtility::mergeRecursiveWithOverrule(
+            $configuration,
+            $this->addFlattenedPageTsConfig($pageTs)
+        );
+
+        // Handle "mode" / "transformation" config when overridden
+        if (!isset($configuration['proc.']['mode']) && !isset($configuration['proc.']['overruleMode'])) {
+            $configuration['proc.']['overruleMode'] = 'default';
+        }
+
+        return $configuration;
+    }
+
+    /**
+     * Load a configuration preset from an external resource (currently only YAML is supported).
+     * This is the default behaviour and can be overridden by pageTSconfig.
+     *
+     * @param string $presetName
+     * @return array the parsed configuration
+     */
+    protected function loadConfigurationFromPreset(string $presetName = ''): array
+    {
+        $configuration = [];
+        if (!empty($presetName) && isset($GLOBALS['TYPO3_CONF_VARS']['RTE']['Presets'][$presetName])) {
+            $fileLoader = GeneralUtility::makeInstance(YamlFileLoader::class);
+            $configuration = $fileLoader->load($GLOBALS['TYPO3_CONF_VARS']['RTE']['Presets'][$presetName]);
+            // For future versions, you should however rely on the "processing" key and not the "proc" key.
+            if (is_array($configuration['processing'])) {
+                $configuration['proc.'] = $this->convertPlainArrayToTypoScriptArray($configuration['processing']);
+            }
+        }
+        return $configuration;
+    }
+
+    /**
+     * Return RTE section of page TS
+     *
+     * @param int $pid Page ts of given pid
+     * @return array RTE section of pageTs of given pid
+     */
+    protected function getRtePageTsConfigOfPid(int $pid): array
+    {
+        return BackendUtility::getPagesTSconfig($pid)['RTE.'] ?? [];
+    }
+
+    /**
+     * Returns an array with Typoscript the old way (with dot)
+     * Since the functionality in YAML is without the dots, but the new configuration is used without the dots
+     * this functionality adds also an explicit = 1 to the arrays
+     *
+     * @param array $plainArray An array
+     * @return array array with TypoScript as usual (with dot)
+     */
+    protected function convertPlainArrayToTypoScriptArray(array $plainArray)
+    {
+        $typoScriptArray = [];
+        foreach ($plainArray as $key => $value) {
+            if (is_array($value)) {
+                if (!isset($typoScriptArray[$key])) {
+                    $typoScriptArray[$key] = 1;
+                }
+                $typoScriptArray[$key . '.'] = $this->convertPlainArrayToTypoScriptArray($value);
+            } else {
+                $typoScriptArray[$key] = $value === null ? '' : $value;
+            }
+        }
+        return $typoScriptArray;
+    }
+
+    /**
+     * Add all PageTS.RTE options keys to configuration without dots
+     *
+     * We need to keep the dotted keys for backwards compatibility like ext:rtehtmlarea
+     *
+     * @param array $typoScriptArray TypoScriptArray
+     * @return array array with config without dots added
+     */
+    protected function addFlattenedPageTsConfig(array $typoScriptArray): array
+    {
+        foreach ($typoScriptArray as $key => $data) {
+            if (substr($key, -1) !== '.') {
+                continue;
+            }
+            /** @var TypoScriptService $typoScriptService */
+            $typoScriptService = GeneralUtility::makeInstance(TypoScriptService::class);
+            $typoScriptArray[substr($key, 0, -1)] = $typoScriptService->convertTypoScriptArrayToPlainArray($typoScriptArray[$key]);
+        }
+
+        return $typoScriptArray;
+    }
+
+    /**
+     * Load PageTS configuration for the RTE
+     *
+     * Return RTE section of page TS, taking into account overloading via table, field and record type
+     *
+     * @param string $table The table the field is in
+     * @param string $field Field name
+     * @param int $pid Real page id
+     * @param string $recordType Record type value
+     * @return array
+     */
+    protected function getPageTsConfiguration(string $table, string $field, int $pid, string $recordType): array
+    {
+        // Load PageTSconfig configuration
+        $fullPageTsConfig = $this->getRtePageTsConfigOfPid($pid);
+        $defaultPageTsConfigOverrides = $fullPageTsConfig['default.'] ?? null;
+        $fieldSpecificPageTsConfigOverrides = $fullPageTsConfig['config.'][$table . '.'][$field . '.'] ?? null;
+        unset($fullPageTsConfig['default.'], $fullPageTsConfig['config.']);
+
+        // First use RTE.*
+        $rtePageTsConfiguration = $fullPageTsConfig;
+
+        // Then overload with RTE.default.*
+        if (is_array($defaultPageTsConfigOverrides)) {
+            ArrayUtility::mergeRecursiveWithOverrule($rtePageTsConfiguration, $defaultPageTsConfigOverrides);
+        }
+
+        // Then overload with RTE.config.tt_content.bodytext
+        if (is_array($fieldSpecificPageTsConfigOverrides)) {
+            $fieldSpecificPageTsConfigOverridesWithoutType = $fieldSpecificPageTsConfigOverrides;
+            unset($fieldSpecificPageTsConfigOverridesWithoutType['types.']);
+            ArrayUtility::mergeRecursiveWithOverrule($rtePageTsConfiguration, $fieldSpecificPageTsConfigOverridesWithoutType);
+
+            // Then overload with RTE.config.tt_content.bodytext.types.textmedia
+            if (
+                $recordType
+                && isset($fieldSpecificPageTsConfigOverrides['types.'][$recordType . '.'])
+                && is_array($fieldSpecificPageTsConfigOverrides['types.'][$recordType . '.'])
+            ) {
+                ArrayUtility::mergeRecursiveWithOverrule(
+                    $rtePageTsConfiguration,
+                    $fieldSpecificPageTsConfigOverrides['types.'][$recordType . '.']
+                );
+            }
+        }
+
+        return $rtePageTsConfiguration;
+    }
+}

typo3/sysext/core/Classes/Configuration/SiteConfiguration.php

@@ -0,0 +1,307 @@
+<?php
+declare(strict_types = 1);
+
+namespace TYPO3\CMS\Core\Configuration;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use Symfony\Component\Finder\Finder;
+use Symfony\Component\Yaml\Yaml;
+use TYPO3\CMS\Core\Cache\CacheManager;
+use TYPO3\CMS\Core\Cache\Frontend\FrontendInterface;
+use TYPO3\CMS\Core\Configuration\Loader\YamlFileLoader;
+use TYPO3\CMS\Core\Exception\SiteNotFoundException;
+use TYPO3\CMS\Core\SingletonInterface;
+use TYPO3\CMS\Core\Site\Entity\Site;
+use TYPO3\CMS\Core\Utility\ArrayUtility;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * Responsibility: Handles the format of the configuration (currently yaml), and the location of the file system folder
+ *
+ * Reads all available site configuration options, and puts them into Site objects.
+ *
+ * @internal
+ */
+class SiteConfiguration implements SingletonInterface
+{
+    /**
+     * @var string
+     */
+    protected $configPath;
+
+    /**
+     * Config yaml file name.
+     *
+     * @internal
+     * @var string
+     */
+    protected $configFileName = 'config.yaml';
+
+    /**
+     * Identifier to store all configuration data in cache_core cache.
+     *
+     * @internal
+     * @var string
+     */
+    protected $cacheIdentifier = 'site-configuration';
+
+    /**
+     * Cache stores all configuration as Site objects, as long as they haven't been changed.
+     * This drastically improves performance as SiteFinder utilizes SiteConfiguration heavily
+     *
+     * @var array|null
+     */
+    protected $firstLevelCache;
+
+    /**
+     * @param string $configPath
+     */
+    public function __construct(string $configPath)
+    {
+        $this->configPath = $configPath;
+    }
+
+    /**
+     * Return all site objects which have been found in the filesystem.
+     *
+     * @param bool $useCache
+     * @return Site[]
+     */
+    public function getAllExistingSites(bool $useCache = true): array
+    {
+        if ($useCache && $this->firstLevelCache !== null) {
+            return $this->firstLevelCache;
+        }
+        return $this->resolveAllExistingSites($useCache);
+    }
+
+    /**
+     * Resolve all site objects which have been found in the filesystem.
+     *
+     * @return Site[]
+     */
+    public function resolveAllExistingSites(): array
+    {
+        $sites = [];
+        $siteConfiguration = $this->getAllSiteConfigurationFromFiles();
+        foreach ($siteConfiguration as $identifier => $configuration) {
+            $rootPageId = (int)($configuration['rootPageId'] ?? 0);
+            if ($rootPageId > 0) {
+                $sites[$identifier] = GeneralUtility::makeInstance(Site::class, $identifier, $rootPageId, $configuration);
+            }
+        }
+        $this->firstLevelCache = $sites;
+        return $sites;
+    }
+
+    /**
+     * Read the site configuration from config files.
+     *
+     * @return array
+     * @throws \TYPO3\CMS\Core\Cache\Exception\NoSuchCacheException
+     */
+    protected function getAllSiteConfigurationFromFiles(): array
+    {
+        // Check if the data is already cached
+        if ($siteConfiguration = $this->getCache()->get($this->cacheIdentifier)) {
+            // Due to the nature of PhpFrontend, the `<?php` and `#` wraps have to be removed
+            $siteConfiguration = preg_replace('/^<\?php\s*|\s*#$/', '', $siteConfiguration);
+            $siteConfiguration = json_decode($siteConfiguration, true);
+        }
+
+        // Nothing in the cache (or no site found)
+        if (empty($siteConfiguration)) {
+            $finder = new Finder();
+            try {
+                $finder->files()->depth(0)->name($this->configFileName)->in($this->configPath . '/*');
+            } catch (\InvalidArgumentException $e) {
+                // Directory $this->configPath does not exist yet
+                $finder = [];
+            }
+            $loader = GeneralUtility::makeInstance(YamlFileLoader::class);
+            $siteConfiguration = [];
+            foreach ($finder as $fileInfo) {
+                $configuration = $loader->load(GeneralUtility::fixWindowsFilePath((string)$fileInfo));
+                $identifier = basename($fileInfo->getPath());
+                if (isset($configuration['site'])) {
+                    trigger_error(
+                        'Site configuration with key \'site\' has been deprecated, remove indentation level and site key.',
+                        E_USER_DEPRECATED
+                    );
+                    $configuration = $configuration['site'];
+                }
+                $siteConfiguration[$identifier] = $configuration;
+            }
+            $this->getCache()->set($this->cacheIdentifier, json_encode($siteConfiguration));
+        }
+        return $siteConfiguration ?? [];
+    }
+
+    /**
+     * Load plain configuration
+     * This method should only be used in case the original configuration as it exists in the file should be loaded,
+     * for example for writing / editing configuration.
+     *
+     * All read related actions should be performed on the site entity.
+     *
+     * @param string $siteIdentifier
+     * @return array
+     */
+    public function load(string $siteIdentifier): array
+    {
+        $fileName = $this->configPath . '/' . $siteIdentifier . '/' . $this->configFileName;
+        $loader = GeneralUtility::makeInstance(YamlFileLoader::class);
+        return $loader->load(GeneralUtility::fixWindowsFilePath($fileName), YamlFileLoader::PROCESS_IMPORTS);
+    }
+
+    /**
+     * Add or update a site configuration
+     *
+     * @param string $siteIdentifier
+     * @param array $configuration
+     * @throws \TYPO3\CMS\Core\Cache\Exception\NoSuchCacheException
+     */
+    public function write(string $siteIdentifier, array $configuration): void
+    {
+        $folder = $this->configPath . '/' . $siteIdentifier;
+        $fileName = $folder . '/' . $this->configFileName;
+        $newConfiguration = $configuration;
+        if (!file_exists($folder)) {
+            GeneralUtility::mkdir_deep($folder);
+        } elseif (file_exists($fileName)) {
+            $loader = GeneralUtility::makeInstance(YamlFileLoader::class);
+            // load without any processing to have the unprocessed base to modify
+            $newConfiguration = $loader->load(GeneralUtility::fixWindowsFilePath($fileName), 0);
+            // load the processed configuration to diff changed values
+            $processed = $loader->load(GeneralUtility::fixWindowsFilePath($fileName));
+            // find properties that were modified via GUI
+            $newModified = array_replace_recursive(
+                self::findRemoved($processed, $configuration),
+                self::findModified($processed, $configuration)
+            );
+            // change _only_ the modified keys, leave the original non-changed areas alone
+            ArrayUtility::mergeRecursiveWithOverrule($newConfiguration, $newModified);
+        }
+        $newConfiguration = $this->sortConfiguration($newConfiguration);
+        $yamlFileContents = Yaml::dump($newConfiguration, 99, 2);
+        GeneralUtility::writeFile($fileName, $yamlFileContents);
+        $this->firstLevelCache = null;
+        $this->getCache()->remove($this->cacheIdentifier);
+        $this->getCache()->remove('pseudo-sites');
+    }
+
+    /**
+     * Renames a site identifier (and moves the folder)
+     *
+     * @param string $currentIdentifier
+     * @param string $newIdentifier
+     * @throws \TYPO3\CMS\Core\Cache\Exception\NoSuchCacheException
+     */
+    public function rename(string $currentIdentifier, string $newIdentifier): void
+    {
+        $result = rename($this->configPath . '/' . $currentIdentifier, $this->configPath . '/' . $newIdentifier);
+        if (!$result) {
+            throw new \RuntimeException('Unable to rename folder sites/' . $currentIdentifier, 1522491300);
+        }
+        $this->getCache()->remove($this->cacheIdentifier);
+        $this->firstLevelCache = null;
+    }
+
+    /**
+     * Removes the config.yaml file of a site configuration.
+     * Also clears the cache.
+     *
+     * @param string $siteIdentifier
+     * @throws SiteNotFoundException
+     */
+    public function delete(string $siteIdentifier): void
+    {
+        $sites = $this->getAllExistingSites();
+        if (!isset($sites[$siteIdentifier])) {
+            throw new SiteNotFoundException('Site configuration named ' . $siteIdentifier . ' not found.', 1522866183);
+        }
+        $fileName = $this->configPath . '/' . $siteIdentifier . '/' . $this->configFileName;
+        if (!file_exists($fileName)) {
+            throw new SiteNotFoundException('Site configuration file ' . $this->configFileName . ' within the site ' . $siteIdentifier . ' not found.', 1522866184);
+        }
+        @unlink($fileName);
+        $this->getCache()->remove($this->cacheIdentifier);
+        $this->getCache()->remove('pseudo-sites');
+        $this->firstLevelCache = null;
+    }
+
+    /**
+     * Short-hand function for the cache
+     *
+     * @return FrontendInterface
+     * @throws \TYPO3\CMS\Core\Cache\Exception\NoSuchCacheException
+     */
+    protected function getCache(): FrontendInterface
+    {
+        return GeneralUtility::makeInstance(CacheManager::class)->getCache('cache_core');
+    }
+
+    /**
+     * @param array $newConfiguration
+     * @return array
+     */
+    protected function sortConfiguration(array $newConfiguration): array
+    {
+        ksort($newConfiguration);
+        if (isset($newConfiguration['imports'])) {
+            $imports = $newConfiguration['imports'];
+            unset($newConfiguration['imports']);
+            $newConfiguration['imports'] = $imports;
+        }
+        return $newConfiguration;
+    }
+
+    protected static function findModified(array $currentConfiguration, array $newConfiguration): array
+    {
+        $differences = [];
+        foreach ($newConfiguration as $key => $value) {
+            if (!isset($currentConfiguration[$key]) || $currentConfiguration[$key] !== $newConfiguration[$key]) {
+                if (!isset($newConfiguration[$key]) && isset($currentConfiguration[$key])) {
+                    $differences[$key] = '__UNSET';
+                } elseif (isset($currentConfiguration[$key])
+                    && is_array($newConfiguration[$key])
+                    && is_array($currentConfiguration[$key])
+                ) {
+                    $differences[$key] = self::findModified($currentConfiguration[$key], $newConfiguration[$key]);
+                } else {
+                    $differences[$key] = $value;
+                }
+            }
+        }
+        return $differences;
+    }
+
+    protected static function findRemoved(array $currentConfiguration, array $newConfiguration): array
+    {
+        $removed = [];
+        foreach ($currentConfiguration as $key => $value) {
+            if (!isset($newConfiguration[$key])) {
+                $removed[$key] = '__UNSET';
+            } elseif (isset($currentConfiguration[$key]) && is_array($currentConfiguration[$key]) && is_array($newConfiguration[$key])) {
+                $removedInRecursion = self::findRemoved($currentConfiguration[$key], $newConfiguration[$key]);
+                if (!empty($removedInRecursion)) {
+                    $removed[$key] = $removedInRecursion;
+                }
+            }
+        }
+
+        return $removed;
+    }
+}

typo3/sysext/core/Classes/Configuration/TypoScript/ConditionMatching/AbstractCondition.php

@@ -0,0 +1,57 @@
+<?php
+namespace TYPO3\CMS\Core\Configuration\TypoScript\ConditionMatching;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * Abstract class to define own custom TypoScript conditions.
+ *
+ * Used with the TypoScript parser.
+ */
+abstract class AbstractCondition
+{
+    /**
+     * @var \TYPO3\CMS\Core\Configuration\TypoScript\ConditionMatching\AbstractConditionMatcher
+     */
+    protected $conditionMatcherInstance;
+
+    /**
+     * @return \TYPO3\CMS\Core\Configuration\TypoScript\ConditionMatching\AbstractConditionMatcher
+     */
+    protected function getConditionMatcherInstance()
+    {
+        return $this->conditionMatcherInstance;
+    }
+
+    /**
+     * @param \TYPO3\CMS\Core\Configuration\TypoScript\ConditionMatching\AbstractConditionMatcher $conditionMatcherInstance
+     */
+    public function setConditionMatcherInstance($conditionMatcherInstance)
+    {
+        $this->conditionMatcherInstance = $conditionMatcherInstance;
+    }
+
+    /**
+     * Main method handling the evaluation.
+     * Any given parameters given within the condition in form of
+     * [ACME\MyPackageName\MyCondition = value1, = value2]
+     * will be given as parameter in form of a numeric array, each entry
+     * containing the strings that are split by the commas
+     * e.g. array('= value1', '= value2')
+     *
+     * @param array $conditionParameters
+     * @return bool
+     */
+    abstract public function matchCondition(array $conditionParameters);
+}

typo3/sysext/core/Classes/Configuration/TypoScript/ConditionMatching/AbstractConditionMatcher.php

@@ -0,0 +1,787 @@
+<?php
+namespace TYPO3\CMS\Core\Configuration\TypoScript\ConditionMatching;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use Psr\Log\LoggerAwareInterface;
+use Psr\Log\LoggerAwareTrait;
+use Symfony\Component\ExpressionLanguage\SyntaxError;
+use TYPO3\CMS\Core\Configuration\Features;
+use TYPO3\CMS\Core\Configuration\TypoScript\Exception\InvalidTypoScriptConditionException;
+use TYPO3\CMS\Core\Error\Exception;
+use TYPO3\CMS\Core\Exception\MissingTsfeException;
+use TYPO3\CMS\Core\ExpressionLanguage\Resolver;
+use TYPO3\CMS\Core\Log\LogLevel;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+use TYPO3\CMS\Core\Utility\StringUtility;
+use TYPO3\CMS\Core\Utility\VersionNumberUtility;
+
+/**
+ * Matching TypoScript conditions
+ *
+ * Used with the TypoScript parser.
+ * Matches IPnumbers etc. for use with templates
+ */
+abstract class AbstractConditionMatcher implements LoggerAwareInterface
+{
+    use LoggerAwareTrait;
+
+    /**
+     * Id of the current page.
+     *
+     * @var int
+     */
+    protected $pageId;
+
+    /**
+     * The rootline for the current page.
+     *
+     * @var array
+     */
+    protected $rootline;
+
+    /**
+     * Whether to simulate the behaviour and match all conditions
+     * (used in TypoScript object browser).
+     *
+     * @var bool
+     */
+    protected $simulateMatchResult = false;
+
+    /**
+     * Whether to simulat the behaviour and match specific conditions
+     * (used in TypoScript object browser).
+     *
+     * @var array
+     */
+    protected $simulateMatchConditions = [];
+
+    /**
+     * @var Resolver
+     */
+    protected $expressionLanguageResolver;
+
+    /**
+     * @var array
+     */
+    protected $expressionLanguageResolverVariables = [];
+
+    protected function initializeExpressionLanguageResolver(): void
+    {
+        $this->updateExpressionLanguageVariables();
+        $this->expressionLanguageResolver = GeneralUtility::makeInstance(
+            Resolver::class,
+            'typoscript',
+            $this->expressionLanguageResolverVariables
+        );
+    }
+
+    protected function updateExpressionLanguageVariables(): void
+    {
+        // deliberately empty and not "abstract" due to backwards compatibility
+        // implement this method in derived classes
+    }
+
+    /**
+     * @return bool
+     */
+    protected function strictSyntaxEnabled(): bool
+    {
+        return GeneralUtility::makeInstance(Features::class)->isFeatureEnabled('TypoScript.strictSyntax');
+    }
+
+    /**
+     * Sets the id of the page to evaluate conditions for.
+     *
+     * @param int $pageId Id of the page (must be positive)
+     */
+    public function setPageId($pageId)
+    {
+        if (is_int($pageId) && $pageId > 0) {
+            $this->pageId = $pageId;
+        }
+        $this->initializeExpressionLanguageResolver();
+    }
+
+    /**
+     * Gets the id of the page to evaluate conditions for.
+     *
+     * @return int Id of the page
+     */
+    public function getPageId()
+    {
+        return $this->pageId;
+    }
+
+    /**
+     * Sets the rootline.
+     *
+     * @param array $rootline The rootline to be used for matching (must have elements)
+     */
+    public function setRootline(array $rootline)
+    {
+        if (!empty($rootline)) {
+            $this->rootline = $rootline;
+        }
+        $this->initializeExpressionLanguageResolver();
+    }
+
+    /**
+     * Gets the rootline.
+     *
+     * @return array The rootline to be used for matching
+     */
+    public function getRootline()
+    {
+        return $this->rootline;
+    }
+
+    /**
+     * Sets whether to simulate the behaviour and match all conditions.
+     *
+     * @param bool $simulateMatchResult Whether to simulate positive matches
+     */
+    public function setSimulateMatchResult($simulateMatchResult)
+    {
+        if (is_bool($simulateMatchResult)) {
+            $this->simulateMatchResult = $simulateMatchResult;
+        }
+    }
+
+    /**
+     * Sets whether to simulate the behaviour and match specific conditions.
+     *
+     * @param array $simulateMatchConditions Conditions to simulate a match for
+     */
+    public function setSimulateMatchConditions(array $simulateMatchConditions)
+    {
+        $this->simulateMatchConditions = $simulateMatchConditions;
+    }
+
+    /**
+     * Normalizes an expression
+     * + OR normalization: "...]OR[...", "...]||[...", "...][..." --> "...]||[..."
+     * + AND normalization: "...]AND[...", "...]&&[..."		   --> "...]&&[..."
+     *
+     * @param string $expression The expression to be normalized (e.g. "[A] && [B] OR [C]")
+     * @return string The normalized expression (e.g. "[A]&&[B]||[C]")
+     * @deprecated since TYPO3 v9.4, will be removed in TYPO3 v10.0.
+     */
+    protected function normalizeExpression($expression)
+    {
+        $removeSpaces = '/
+          \\s*
+          (                    # subroutine 1
+            \\[
+              (?:
+                [^\\[\\]]      # any character except []
+                | (?1)         # recursive subroutine 1 when brackets are around
+              )*
+            \\]
+          )
+          \\s*
+          /xi';
+
+        $adjacentBrackets = '/
+          (                    # subroutine 1
+            \\[
+              (?:
+                [^\\[\\]]      # any character except []
+                | (?1)         # recursive subroutine 1 when brackets are around
+              )*
+            \\]
+          )
+          (*SKIP)              # avoid backtracking into completed bracket expressions
+          \\[                  # match the following [
+          /xi';
+
+        return preg_replace(
+            [
+                $removeSpaces,
+                '/\\]AND\\[/i',
+                '/\\]OR\\[/i',
+                $adjacentBrackets
+            ],
+            [
+                '\\1',
+                ']&&[',
+                ']||[',
+                '\\1||['
+            ],
+            trim($expression)
+        );
+    }
+
+    /**
+     * Matches a TypoScript condition expression.
+     *
+     * @param string $expression The expression to match
+     * @return bool Whether the expression matched
+     */
+    public function match($expression)
+    {
+        // Return directly if result should be simulated:
+        if ($this->simulateMatchResult) {
+            return $this->simulateMatchResult;
+        }
+        // Return directly if matching for specific condition is simulated only:
+        if (!empty($this->simulateMatchConditions)) {
+            return in_array($expression, $this->simulateMatchConditions);
+        }
+        // Sets the current pageId if not defined yet:
+        if (!isset($this->pageId)) {
+            $this->pageId = $this->determinePageId();
+        }
+        // Sets the rootline if not defined yet:
+        if (!isset($this->rootline)) {
+            $this->rootline = $this->determineRootline();
+        }
+        $result = false;
+        $normalizedExpression = $this->normalizeExpression($expression);
+        // First and last character must be square brackets (e.g. "[A]&&[B]":
+        if ($normalizedExpression[0] === '[' && substr($normalizedExpression, -1) === ']') {
+            $innerExpression = substr($normalizedExpression, 1, -1);
+            $orParts = explode(']||[', $innerExpression);
+            if ($this->strictSyntaxEnabled() && count($orParts) > 1) {
+                trigger_error('Multiple conditions blocks combined with AND, OR, && or || will be removed in TYPO3 v10.0, use the new expression language.', E_USER_DEPRECATED);
+            }
+            foreach ($orParts as $orPart) {
+                $andParts = explode(']&&[', $orPart);
+                if ($this->strictSyntaxEnabled() && count($andParts) > 1) {
+                    trigger_error('Multiple conditions blocks combined with AND, OR, && or || will be removed in TYPO3 v10.0, use the new expression language.', E_USER_DEPRECATED);
+                }
+                foreach ($andParts as $andPart) {
+                    $result = $this->evaluateExpression($andPart);
+                    if (!is_bool($result)) {
+                        $result = $this->evaluateCondition($andPart);
+                    }
+                    // If condition in AND context fails, the whole block is FALSE:
+                    if ($result === false) {
+                        break;
+                    }
+                }
+                // If condition in OR context succeeds, the whole expression is TRUE:
+                if ($result === true) {
+                    break;
+                }
+            }
+        }
+        return $result;
+    }
+
+    /**
+     * @param string $expression
+     * @return bool|null
+     */
+    protected function evaluateExpression(string $expression): ?bool
+    {
+        try {
+            $result = $this->expressionLanguageResolver->evaluate($expression);
+            if ($result !== null) {
+                return $result;
+            }
+        } catch (MissingTsfeException $e) {
+            // TSFE is not available in the current context (e.g. TSFE in BE context),
+            // we set all conditions false for this case.
+            return false;
+        } catch (SyntaxError $exception) {
+            // SyntaxException means no support, let's try the fallback
+            $message = 'Expression could not be parsed, fallback kicks in.';
+            if (strpos($exception->getMessage(), 'Unexpected character "="') !== false) {
+                $message .= ' It looks like an old condition with only one equal sign.';
+            }
+            $this->logger->log(
+                $this->strictSyntaxEnabled() ? LogLevel::WARNING : LogLevel::INFO,
+                $message,
+                ['expression' => $expression]
+            );
+        } catch (\Throwable $exception) {
+            // The following error handling is required to mitigate a missing type check
+            // in the Symfony Expression Language handling. In case a condition
+            // use "in" or "not in" check in combination with a non array a PHP Warning
+            // is thrown. Example: [1 in "foo"] or ["bar" in "foo,baz"]
+            // This conditions are wrong for sure, but they will break the complete installation
+            // including the backend. To mitigate the problem we do the following:
+            // 1) In FE an InvalidTypoScriptConditionException is thrown (if strictSyntax is enabled)
+            // 2) In FE silent catch this error and log it (if strictSyntax is disabled)
+            // 3) In BE silent catch this error and log it, but never break the backend.
+            $this->logger->error($exception->getMessage(), [
+                'expression' => $expression,
+                'exception' => $exception
+            ]);
+            if (TYPO3_MODE === 'FE'
+                && $exception instanceof Exception
+                && $this->strictSyntaxEnabled()
+                && strpos($exception->getMessage(), 'in_array() expects parameter 2 to be array') !== false
+            ) {
+                throw new InvalidTypoScriptConditionException('Invalid expression in condition: [' . $expression . ']', 1536950931);
+            }
+        }
+        return null;
+    }
+
+    /**
+     * Evaluates a TypoScript condition given as input, eg. "[applicationContext = Production][...(other condition)...]"
+     *
+     * @param string $key The condition to match against its criteria.
+     * @param string $value
+     * @return bool|null Result of the evaluation; NULL if condition could not be evaluated
+     * @deprecated since TYPO3 v9.4, will be removed in TYPO3 v10.0.
+     */
+    protected function evaluateConditionCommon($key, $value)
+    {
+        $keyParts = GeneralUtility::trimExplode('|', $key);
+        switch ($keyParts[0]) {
+            case 'applicationContext':
+                $values = GeneralUtility::trimExplode(',', $value, true);
+                $currentApplicationContext = GeneralUtility::getApplicationContext();
+                foreach ($values as $applicationContext) {
+                    if ($this->searchStringWildcard($currentApplicationContext, $applicationContext)) {
+                        return true;
+                    }
+                }
+                return false;
+            case 'language':
+                if (GeneralUtility::getIndpEnv('HTTP_ACCEPT_LANGUAGE') === $value) {
+                    return true;
+                }
+                $values = GeneralUtility::trimExplode(',', $value, true);
+                foreach ($values as $test) {
+                    // matches a string with asterix in front and back. See https://docs.typo3.org/typo3cms/TyposcriptReference/Conditions/Reference.html#language for use case.
+                    if (preg_match('/^\\*.+\\*$/', $test)) {
+                        $allLanguages = preg_split('/[,;]/', GeneralUtility::getIndpEnv('HTTP_ACCEPT_LANGUAGE'));
+                        if (in_array(substr($test, 1, -1), $allLanguages)) {
+                            return true;
+                        }
+                    } elseif (GeneralUtility::getIndpEnv('HTTP_ACCEPT_LANGUAGE') == $test) {
+                        return true;
+                    }
+                }
+                return false;
+            case 'IP':
+                if ($value === 'devIP') {
+                    $value = trim($GLOBALS['TYPO3_CONF_VARS']['SYS']['devIPmask']);
+                }
+
+                return (bool)GeneralUtility::cmpIP(GeneralUtility::getIndpEnv('REMOTE_ADDR'), $value);
+            case 'hostname':
+                return (bool)GeneralUtility::cmpFQDN(GeneralUtility::getIndpEnv('REMOTE_ADDR'), $value);
+            case 'hour':
+            case 'minute':
+            case 'month':
+            case 'year':
+            case 'dayofweek':
+            case 'dayofmonth':
+            case 'dayofyear':
+                // In order to simulate time properly in templates.
+                $theEvalTime = $GLOBALS['SIM_EXEC_TIME'];
+                switch ($key) {
+                    case 'hour':
+                        $theTestValue = date('H', $theEvalTime);
+                        break;
+                    case 'minute':
+                        $theTestValue = date('i', $theEvalTime);
+                        break;
+                    case 'month':
+                        $theTestValue = date('m', $theEvalTime);
+                        break;
+                    case 'year':
+                        $theTestValue = date('Y', $theEvalTime);
+                        break;
+                    case 'dayofweek':
+                        $theTestValue = date('w', $theEvalTime);
+                        break;
+                    case 'dayofmonth':
+                        $theTestValue = date('d', $theEvalTime);
+                        break;
+                    case 'dayofyear':
+                        $theTestValue = date('z', $theEvalTime);
+                        break;
+                    default:
+                        $theTestValue = 0;
+                        break;
+                }
+                $theTestValue = (int)$theTestValue;
+                // comp
+                $values = GeneralUtility::trimExplode(',', $value, true);
+                foreach ($values as $test) {
+                    if (\TYPO3\CMS\Core\Utility\MathUtility::canBeInterpretedAsInteger($test)) {
+                        $test = '=' . $test;
+                    }
+                    if ($this->compareNumber($test, $theTestValue)) {
+                        return true;
+                    }
+                }
+                return false;
+            case 'compatVersion':
+                return VersionNumberUtility::convertVersionNumberToInteger(TYPO3_branch) >= VersionNumberUtility::convertVersionNumberToInteger($value);
+            case 'loginUser':
+                if ($this->isUserLoggedIn()) {
+                    $values = GeneralUtility::trimExplode(',', $value, true);
+                    foreach ($values as $test) {
+                        if ($test === '*' || (string)$this->getUserId() === (string)$test) {
+                            return true;
+                        }
+                    }
+                } elseif ($value === '') {
+                    return true;
+                }
+                return false;
+            case 'page':
+                if ($keyParts[1]) {
+                    $page = $this->getPage();
+                    $property = $keyParts[1];
+                    if (!empty($page) && isset($page[$property]) && (string)$page[$property] === (string)$value) {
+                        return true;
+                    }
+                }
+                return false;
+            case 'globalVar':
+                $values = GeneralUtility::trimExplode(',', $value, true);
+                foreach ($values as $test) {
+                    $point = strcspn($test, '!=<>');
+                    $theVarName = substr($test, 0, $point);
+                    $nv = $this->getVariable(trim($theVarName));
+                    $testValue = substr($test, $point);
+                    if ($this->compareNumber($testValue, $nv)) {
+                        return true;
+                    }
+                }
+                return false;
+            case 'globalString':
+                $values = GeneralUtility::trimExplode(',', $value, true);
+                foreach ($values as $test) {
+                    $point = strcspn($test, '=');
+                    $theVarName = substr($test, 0, $point);
+                    $nv = (string)$this->getVariable(trim($theVarName));
+                    $testValue = substr($test, $point + 1);
+                    if ($this->searchStringWildcard($nv, trim($testValue))) {
+                        return true;
+                    }
+                }
+                return false;
+            case 'userFunc':
+                $matches = [];
+                preg_match_all('/^\s*([^\(\s]+)\s*(?:\((.*)\))?\s*$/', $value, $matches);
+                $funcName = $matches[1][0];
+                $funcValues = trim($matches[2][0]) !== '' ? $this->parseUserFuncArguments($matches[2][0]) : [];
+                if (is_callable($funcName) && call_user_func_array($funcName, $funcValues)) {
+                    return true;
+                }
+                return false;
+        }
+        return null;
+    }
+
+    /**
+     * Evaluates a TypoScript condition given as input with a custom class name,
+     * e.g. "[MyCompany\MyPackage\ConditionMatcher\MyOwnConditionMatcher = myvalue]"
+     *
+     * @param string $condition The condition to match
+     * @return bool|null Result of the evaluation; NULL if condition could not be evaluated
+     * @throws \TYPO3\CMS\Core\Configuration\TypoScript\Exception\InvalidTypoScriptConditionException
+     * @deprecated since TYPO3 v9.4, will be removed in TYPO3 v10.0.
+     */
+    protected function evaluateCustomDefinedCondition($condition)
+    {
+        $conditionResult = null;
+
+        list($conditionClassName, $conditionParameters) = GeneralUtility::trimExplode(' ', $condition, false, 2);
+
+        // Check if the condition class name is a valid class
+        // This is necessary to not stop here for the conditions ELSE and GLOBAL
+        if (class_exists($conditionClassName)) {
+            // Use like this: [MyCompany\MyPackage\ConditionMatcher\MyOwnConditionMatcher = myvalue]
+            /** @var \TYPO3\CMS\Core\Configuration\TypoScript\ConditionMatching\AbstractCondition $conditionObject */
+            $conditionObject = GeneralUtility::makeInstance($conditionClassName);
+            if (($conditionObject instanceof \TYPO3\CMS\Core\Configuration\TypoScript\ConditionMatching\AbstractCondition) === false) {
+                throw new \TYPO3\CMS\Core\Configuration\TypoScript\Exception\InvalidTypoScriptConditionException(
+                    '"' . $conditionClassName . '" is not a valid TypoScript Condition object.',
+                    1410286153
+                );
+            }
+
+            $conditionParameters = $this->parseUserFuncArguments($conditionParameters);
+            $conditionObject->setConditionMatcherInstance($this);
+            $conditionResult = $conditionObject->matchCondition($conditionParameters);
+        }
+
+        return $conditionResult;
+    }
+
+    /**
+     * Parses arguments to the userFunc.
+     *
+     * @param string $arguments
+     * @return array
+     * @deprecated since TYPO3 v9.4, will be removed in TYPO3 v10.0.
+     */
+    protected function parseUserFuncArguments($arguments)
+    {
+        $result = [];
+        $arguments = trim($arguments);
+        while ($arguments !== '') {
+            if ($arguments[0] === ',') {
+                $result[] = '';
+                $arguments = substr($arguments, 1);
+            } else {
+                $pos = strcspn($arguments, ',\'"');
+                if ($pos == 0) {
+                    // We hit a quote of some kind
+                    $quote = $arguments[0];
+                    $segment = preg_replace('/^(.*?[^\\\])' . $quote . '.*$/', '\1', substr($arguments, 1));
+                    $segment = str_replace('\\' . $quote, $quote, $segment);
+                    $result[] = $segment;
+                    // shorten $arguments
+                    $arguments = substr($arguments, strlen($segment) + 2);
+                    $offset = strpos($arguments, ',');
+                    if ($offset === false) {
+                        $offset = strlen($arguments);
+                    }
+                    $arguments = substr($arguments, $offset + 1);
+                } else {
+                    $result[] = trim(substr($arguments, 0, $pos));
+                    $arguments = substr($arguments, $pos + 1);
+                }
+            }
+            $arguments = trim($arguments);
+        }
+        return $result;
+    }
+
+    /**
+     * Get variable common
+     *
+     * @param array $vars
+     * @return mixed Whatever value. If none, then NULL.
+     * @deprecated since TYPO3 v9.4, will be removed in TYPO3 v10.0.
+     */
+    protected function getVariableCommon(array $vars)
+    {
+        $value = null;
+        $namespace = trim($vars[0]);
+        if (count($vars) === 1) {
+            $value = $this->getGlobal($vars[0]);
+        } elseif ($namespace === 'LIT') {
+            $value = trim($vars[1]);
+        } else {
+            $splitAgain = explode('|', $vars[1], 2);
+            $k = trim($splitAgain[0]);
+            if ($k) {
+                switch ($namespace) {
+                    case 'GP':
+                        $value = GeneralUtility::_GP($k);
+                        break;
+                    case 'GPmerged':
+                        $value = GeneralUtility::_GPmerged($k);
+                        break;
+                    case 'ENV':
+                        $value = getenv($k);
+                        break;
+                    case 'IENV':
+                        $value = GeneralUtility::getIndpEnv($k);
+                        break;
+                    default:
+                        return null;
+                }
+                // If array:
+                if (count($splitAgain) > 1) {
+                    if (is_array($value) && trim($splitAgain[1]) !== '') {
+                        $value = $this->getGlobal($splitAgain[1], $value);
+                    } else {
+                        $value = '';
+                    }
+                }
+            }
+        }
+        return $value;
+    }
+
+    /**
+     * Evaluates a $leftValue based on an operator: "<", ">", "<=", ">=", "!=" or "="
+     *
+     * @param string $test The value to compare with on the form [operator][number]. Eg. "< 123
+     * @param float $leftValue The value on the left side
+     * @return bool If $value is "50" and $test is "< 123" then it will return TRUE.
+     * @deprecated since TYPO3 v9.4, will be removed in TYPO3 v10.0.
+     */
+    protected function compareNumber($test, $leftValue)
+    {
+        if (preg_match('/^(!?=+|<=?|>=?)\\s*([^\\s]*)\\s*$/', $test, $matches)) {
+            $operator = $matches[1];
+            $rightValue = $matches[2];
+            switch ($operator) {
+                case '>=':
+                    return $leftValue >= (float)$rightValue;
+                    break;
+                case '<=':
+                    return $leftValue <= (float)$rightValue;
+                    break;
+                case '!=':
+                    // multiple values may be split with '|'
+                    // see if none matches ("not in list")
+                    $found = false;
+                    $rightValueParts = GeneralUtility::trimExplode('|', $rightValue);
+                    foreach ($rightValueParts as $rightValueSingle) {
+                        if ($leftValue == (float)$rightValueSingle) {
+                            $found = true;
+                            break;
+                        }
+                    }
+                    return $found === false;
+                    break;
+                case '<':
+                    return $leftValue < (float)$rightValue;
+                    break;
+                case '>':
+                    return $leftValue > (float)$rightValue;
+                    break;
+                default:
+                    // nothing valid found except '=', use '='
+                    // multiple values may be split with '|'
+                    // see if one matches ("in list")
+                    $found = false;
+                    $rightValueParts = GeneralUtility::trimExplode('|', $rightValue);
+                    foreach ($rightValueParts as $rightValueSingle) {
+                        if ($leftValue == $rightValueSingle) {
+                            $found = true;
+                            break;
+                        }
+                    }
+                    return $found;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * Matching two strings against each other, supporting a "*" wildcard or (if wrapped in "/") PCRE regular expressions
+     *
+     * @param string $haystack The string in which to find $needle.
+     * @param string $needle The string to find in $haystack
+     * @return bool Returns TRUE if $needle matches or is found in (according to wildcards) in $haystack. Eg. if $haystack is "Netscape 6.5" and $needle is "Net*" or "Net*ape" then it returns TRUE.
+     * @deprecated since TYPO3 v9.4, will be removed in TYPO3 v10.0.
+     */
+    protected function searchStringWildcard($haystack, $needle)
+    {
+        return StringUtility::searchStringWildcard($haystack, $needle);
+    }
+
+    /**
+     * Return global variable where the input string $var defines array keys separated by "|"
+     * Example: $var = "HTTP_SERVER_VARS | something" will return the value $GLOBALS['HTTP_SERVER_VARS']['something'] value
+     *
+     * @param string $var Global var key, eg. "HTTP_GET_VAR" or "HTTP_GET_VARS|id" to get the GET parameter "id" back.
+     * @param array $source Alternative array than $GLOBAL to get variables from.
+     * @return mixed Whatever value. If none, then blank string.
+     * @deprecated since TYPO3 v9.4, will be removed in TYPO3 v10.0.
+     */
+    protected function getGlobal($var, $source = null)
+    {
+        $vars = explode('|', $var);
+        $c = count($vars);
+        $k = trim($vars[0]);
+        $theVar = isset($source) ? ($source[$k] ?? null) : ($GLOBALS[$k] ?? null);
+        for ($a = 1; $a < $c; $a++) {
+            if (!isset($theVar)) {
+                break;
+            }
+            $key = trim($vars[$a]);
+            if (is_object($theVar)) {
+                $theVar = $theVar->{$key};
+            } elseif (is_array($theVar)) {
+                $theVar = $theVar[$key];
+            } else {
+                return '';
+            }
+        }
+        if (!is_array($theVar) && !is_object($theVar)) {
+            return $theVar;
+        }
+        return '';
+    }
+
+    /**
+     * Evaluates a TypoScript condition given as input, eg. "[browser=net][...(other conditions)...]"
+     *
+     * @param string $string The condition to match against its criteria.
+     * @return bool Whether the condition matched
+     * @see \TYPO3\CMS\Core\TypoScript\Parser\TypoScriptParser::parse()
+     * @deprecated since TYPO3 v9.4, will be removed in TYPO3 v10.0.
+     */
+    abstract protected function evaluateCondition($string);
+
+    /**
+     * Gets the value of a variable.
+     *
+     * Examples of names:
+     * + TSFE:id
+     * + GP:firstLevel|secondLevel
+     * + _GET|firstLevel|secondLevel
+     * + LIT:someLiteralValue
+     *
+     * @param string $name The name of the variable to fetch the value from
+     * @return mixed The value of the given variable (string) or NULL if variable did not exist
+     * @deprecated since TYPO3 v9.4, will be removed in TYPO3 v10.0.
+     */
+    abstract protected function getVariable($name);
+
+    /**
+     * Gets the usergroup list of the current user.
+     *
+     * @return string The usergroup list of the current user
+     * @deprecated since TYPO3 v9.4, will be removed in TYPO3 v10.0.
+     */
+    abstract protected function getGroupList();
+
+    /**
+     * Determines the current page Id.
+     *
+     * @return int The current page Id
+     * @deprecated since TYPO3 v9.4, will be removed in TYPO3 v10.0.
+     */
+    abstract protected function determinePageId();
+
+    /**
+     * Gets the properties for the current page.
+     *
+     * @return array The properties for the current page.
+     * @deprecated since TYPO3 v9.4, will be removed in TYPO3 v10.0.
+     */
+    abstract protected function getPage();
+
+    /**
+     * Determines the rootline for the current page.
+     *
+     * @return array The rootline for the current page.
+     * @deprecated since TYPO3 v9.4, will be removed in TYPO3 v10.0.
+     */
+    abstract protected function determineRootline();
+
+    /**
+     * Gets the id of the current user.
+     *
+     * @return int The id of the current user
+     * @deprecated since TYPO3 v9.4, will be removed in TYPO3 v10.0.
+     */
+    abstract protected function getUserId();
+
+    /**
+     * Determines if a user is logged in.
+     *
+     * @return bool Determines if a user is logged in
+     * @deprecated since TYPO3 v9.4, will be removed in TYPO3 v10.0.
+     */
+    abstract protected function isUserLoggedIn();
+}

typo3/sysext/core/Classes/Configuration/TypoScript/Exception/InvalidTypoScriptConditionException.php

@@ -0,0 +1,24 @@
+<?php
+namespace TYPO3\CMS\Core\Configuration\TypoScript\Exception;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+/**
+ * A "Your TypoScript condition is invalid" exception
+ * used when a TypoScript condition is called but not extending
+ * from the AbstractCondition class.
+ */
+class InvalidTypoScriptConditionException extends \TYPO3\CMS\Core\Exception
+{
+}

typo3/sysext/core/Classes/Console/CommandApplication.php

@@ -0,0 +1,78 @@
+<?php
+namespace TYPO3\CMS\Core\Console;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+use Symfony\Component\Console\Input\ArgvInput;
+use TYPO3\CMS\Core\Context\Context;
+use TYPO3\CMS\Core\Context\DateTimeAspect;
+use TYPO3\CMS\Core\Context\UserAspect;
+use TYPO3\CMS\Core\Context\VisibilityAspect;
+use TYPO3\CMS\Core\Context\WorkspaceAspect;
+use TYPO3\CMS\Core\Core\ApplicationInterface;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * Entry point for the TYPO3 Command Line for Commands
+ * Does not run the RequestHandler as this already runs an Application inside an Application which
+ * is just way too much logic around simple CLI calls
+ */
+class CommandApplication implements ApplicationInterface
+{
+    /**
+     */
+    public function __construct()
+    {
+        $this->checkEnvironmentOrDie();
+    }
+
+    /**
+     * Run the Symfony Console application in this TYPO3 application
+     *
+     * @param callable $execute
+     */
+    public function run(callable $execute = null)
+    {
+        $this->initializeContext();
+        $handler = GeneralUtility::makeInstance(CommandRequestHandler::class);
+        $handler->handleRequest(new ArgvInput());
+
+        if ($execute !== null) {
+            call_user_func($execute);
+        }
+    }
+
+    /**
+     * Check the script is called from a cli environment.
+     */
+    protected function checkEnvironmentOrDie()
+    {
+        if (PHP_SAPI !== 'cli') {
+            die('Not called from a command line interface (e.g. a shell or scheduler).' . LF);
+        }
+    }
+
+    /**
+     * Initializes the Context used for accessing data and finding out the current state of the application
+     * Will be moved to a DI-like concept once introduced, for now, this is a singleton
+     */
+    protected function initializeContext()
+    {
+        GeneralUtility::makeInstance(Context::class, [
+            'date' => new DateTimeAspect(new \DateTimeImmutable('@' . $GLOBALS['EXEC_TIME'])),
+            'visibility' => new VisibilityAspect(true, true),
+            'workspace' => new WorkspaceAspect(0),
+            'backend.user' => new UserAspect(null),
+        ]);
+    }
+}

typo3/sysext/core/Classes/Console/CommandNameAlreadyInUseException.php

@@ -0,0 +1,25 @@
+<?php
+namespace TYPO3\CMS\Core\Console;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Exception;
+
+/**
+ * Exception thrown when a command is registered with a name
+ * that is already taken
+ */
+class CommandNameAlreadyInUseException extends Exception
+{
+}

typo3/sysext/core/Classes/Console/CommandRegistry.php

@@ -0,0 +1,145 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Console;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use Symfony\Component\Console\Command\Command;
+use TYPO3\CMS\Core\Package\PackageManager;
+use TYPO3\CMS\Core\SingletonInterface;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * Registry for Symfony commands, populated from extensions
+ */
+class CommandRegistry implements \IteratorAggregate, SingletonInterface
+{
+    /**
+     * @var PackageManager
+     */
+    protected $packageManager;
+
+    /**
+     * Map of commands
+     *
+     * @var Command[]
+     */
+    protected $commands = [];
+
+    /**
+     * Map of command configurations with the command name as key
+     *
+     * @var array[]
+     */
+    protected $commandConfigurations = [];
+
+    /**
+     * @param PackageManager $packageManager
+     */
+    public function __construct(PackageManager $packageManager = null)
+    {
+        $this->packageManager = $packageManager ?: GeneralUtility::makeInstance(PackageManager::class);
+    }
+
+    /**
+     * @return \Generator
+     */
+    public function getIterator(): \Generator
+    {
+        $this->populateCommandsFromPackages();
+        foreach ($this->commands as $commandName => $command) {
+            yield $commandName => $command;
+        }
+    }
+
+    /**
+     * Get all commands which are allowed for scheduling recurring commands.
+     *
+     * @return \Generator
+     */
+    public function getSchedulableCommands(): \Generator
+    {
+        $this->populateCommandsFromPackages();
+        foreach ($this->commands as $commandName => $command) {
+            if ($this->commandConfigurations[$commandName]['schedulable'] ?? true) {
+                yield $commandName => $command;
+            }
+        }
+    }
+
+    /**
+     * @param string $identifier
+     * @throws CommandNameAlreadyInUseException
+     * @throws UnknownCommandException
+     * @return Command|null
+     */
+    public function getCommandByIdentifier(string $identifier): ?Command
+    {
+        $this->populateCommandsFromPackages();
+
+        if (!isset($this->commands[$identifier])) {
+            throw new UnknownCommandException(
+                sprintf('Command "%s" has not been registered.', $identifier),
+                1510906768
+            );
+        }
+
+        return $this->commands[$identifier] ?? null;
+    }
+
+    /**
+     * Find all Configuration/Commands.php files of extensions and create a registry from it.
+     * The file should return an array with a command key as key and the command description
+     * as value. The command description must be an array and have a class key that defines
+     * the class name of the command. Example:
+     *
+     * <?php
+     * return [
+     *     'backend:lock' => [
+     *         'class' => \TYPO3\CMS\Backend\Command\LockBackendCommand::class
+     *     ],
+     * ];
+     *
+     * @throws CommandNameAlreadyInUseException
+     */
+    protected function populateCommandsFromPackages()
+    {
+        if ($this->commands) {
+            return;
+        }
+        foreach ($this->packageManager->getActivePackages() as $package) {
+            $commandsOfExtension = $package->getPackagePath() . 'Configuration/Commands.php';
+            if (@is_file($commandsOfExtension)) {
+                /*
+                 * We use require instead of require_once here because it eases the testability as require_once returns
+                 * a boolean from the second execution on. As this class is a singleton, this require is only called
+                 * once per request anyway.
+                 */
+                $commands = require $commandsOfExtension;
+                if (is_array($commands)) {
+                    foreach ($commands as $commandName => $commandConfig) {
+                        if (array_key_exists($commandName, $this->commands)) {
+                            throw new CommandNameAlreadyInUseException(
+                                'Command "' . $commandName . '" registered by "' . $package->getPackageKey() . '" is already in use',
+                                1484486383
+                            );
+                        }
+                        $this->commands[$commandName] = GeneralUtility::makeInstance($commandConfig['class'], $commandName);
+                        $this->commandConfigurations[$commandName] = $commandConfig;
+                    }
+                }
+            }
+        }
+    }
+}

typo3/sysext/core/Classes/Console/CommandRequestHandler.php

@@ -0,0 +1,101 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Console;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use Symfony\Component\Console\Application;
+use Symfony\Component\Console\Command\Command;
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Output\ConsoleOutput;
+use TYPO3\CMS\Core\Authentication\CommandLineUserAuthentication;
+use TYPO3\CMS\Core\Core\Bootstrap;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * Command Line Interface Request Handler dealing with registered commands.
+ */
+class CommandRequestHandler implements RequestHandlerInterface
+{
+    /**
+     * Instance of the symfony application
+     * @var Application
+     */
+    protected $application;
+
+    /**
+     * Constructor initializing the symfony application
+     */
+    public function __construct()
+    {
+        $this->application = new Application('TYPO3 CMS', TYPO3_version);
+    }
+
+    /**
+     * Handles any commandline request
+     *
+     * @param InputInterface $input
+     */
+    public function handleRequest(InputInterface $input)
+    {
+        $output = new ConsoleOutput();
+
+        Bootstrap::loadExtTables();
+        // create the BE_USER object (not logged in yet)
+        Bootstrap::initializeBackendUser(CommandLineUserAuthentication::class);
+        Bootstrap::initializeLanguageObject();
+        // Make sure output is not buffered, so command-line output and interaction can take place
+        ob_clean();
+
+        $this->populateAvailableCommands();
+
+        $exitCode = $this->application->run($input, $output);
+        exit($exitCode);
+    }
+
+    /**
+     * This request handler can handle any CLI request
+     *
+     * @param InputInterface $input
+     * @return bool Always TRUE
+     */
+    public function canHandleRequest(InputInterface $input): bool
+    {
+        return true;
+    }
+
+    /**
+     * Returns the priority - how eager the handler is to actually handle the request.
+     *
+     * @return int The priority of the request handler.
+     */
+    public function getPriority(): int
+    {
+        return 50;
+    }
+
+    /**
+     * Put all available commands inside the application
+     * @throws \TYPO3\CMS\Core\Console\CommandNameAlreadyInUseException
+     */
+    protected function populateAvailableCommands()
+    {
+        $commands = GeneralUtility::makeInstance(CommandRegistry::class);
+
+        foreach ($commands as $commandName => $command) {
+            /** @var Command $command */
+            $this->application->add($command);
+        }
+    }
+}

typo3/sysext/core/Classes/Console/RequestHandlerInterface.php

@@ -0,0 +1,50 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Console;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+use Symfony\Component\Console\Input\InputInterface;
+use Symfony\Component\Console\Output\OutputInterface;
+
+/**
+ * The interface for a request handler for a console-based application
+ */
+interface RequestHandlerInterface
+{
+    /**
+     * Handles a CLI request
+     *
+     * @param InputInterface $input
+     * @return OutputInterface|null
+     */
+    public function handleRequest(InputInterface $input);
+
+    /**
+     * Checks if the request handler can handle the given request.
+     *
+     * @param InputInterface $input
+     * @return bool TRUE if it can handle the request, otherwise FALSE
+     */
+    public function canHandleRequest(InputInterface $input);
+
+    /**
+     * Returns the priority - how eager the handler is to actually handle the
+     * request. An integer > 0 means "I want to handle this request" where
+     * "100" is default. "0" means "I am a fallback solution".
+     *
+     * @return int The priority of the request handler
+     * @internal will get removed from the interface soon as this is not needed in TYPO3 v10.0 anymore.
+     */
+    public function getPriority();
+}

typo3/sysext/core/Classes/Console/UnknownCommandException.php

@@ -0,0 +1,25 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Console;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Exception;
+
+/**
+ * Exception thrown when an unregistered command is asked for
+ */
+class UnknownCommandException extends Exception
+{
+}

typo3/sysext/core/Classes/Context/AspectInterface.php

@@ -0,0 +1,34 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Context;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Context\Exception\AspectPropertyNotFoundException;
+
+/**
+ * Interface AspectInterface
+ * Think of an aspect like a property bag
+ */
+interface AspectInterface
+{
+    /**
+     * Get a property from an aspect
+     *
+     * @param string $name
+     * @return mixed
+     * @throws AspectPropertyNotFoundException
+     */
+    public function get(string $name);
+}

typo3/sysext/core/Classes/Context/Context.php

@@ -0,0 +1,146 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Context;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Context\Exception\AspectNotFoundException;
+use TYPO3\CMS\Core\Context\Exception\AspectPropertyNotFoundException;
+use TYPO3\CMS\Core\SingletonInterface;
+
+/**
+ * Contains the state of a current page request, to be used when reading
+ * information of the current request in which configuration/context
+ * it is used.
+ *
+ * Typically, the current main context is initialized very early within each entry-point application,
+ * and is then modified overridden in e.g. PSR-15 middlewares (e.g. authentication, preview settings etc).
+ *
+ * For most use-cases, the current main context is fetched via GeneralUtility::makeInstance(Context::class),
+ * however, if custom settings for a single use-case is necessary, it is recommended to clone the base context:
+ *
+ * $mainContext = GeneralUtility::makeInstance(Context::class);
+ * $customContext = clone $mainContext;
+ * $customContext->setAspect(GeneralUtility::makeInstance(VisibilityAspect::class, true, true, false))
+ *
+ * ... which in turn can be injected in the various places where TYPO3 uses contexts.
+ *
+ *
+ * Classic aspect names to be used are:
+ * - date (DateTimeAspect)
+ * - workspace
+ * - visibility
+ * - frontend.user
+ * - backend.user
+ * - language
+ */
+class Context implements SingletonInterface
+{
+    /**
+     * @var AspectInterface[]
+     */
+    protected $aspects = [];
+
+    /**
+     * Sets up the context with pre-defined aspects
+     *
+     * @param array|null $defaultAspects
+     */
+    public function __construct(array $defaultAspects = [])
+    {
+        foreach ($defaultAspects as $name => $defaultAspect) {
+            if ($defaultAspect instanceof AspectInterface) {
+                $this->aspects[$name] = $defaultAspect;
+            }
+        }
+        // Ensure the default aspects are set, this is mostly necessary for tests to not set up everything
+        if (!$this->hasAspect('date')) {
+            $time = $GLOBALS['EXEC_TIME'] ?? time();
+            $this->setAspect('date', new DateTimeAspect(new \DateTimeImmutable('@' . $time)));
+        }
+        if (!$this->hasAspect('visibility')) {
+            $this->setAspect('visibility', new VisibilityAspect());
+        }
+        if (!$this->hasAspect('backend.user')) {
+            $this->setAspect('backend.user', new UserAspect());
+        }
+        if (!$this->hasAspect('frontend.user')) {
+            $this->setAspect('frontend.user', new UserAspect());
+        }
+        if (!$this->hasAspect('workspace')) {
+            $this->setAspect('workspace', new WorkspaceAspect());
+        }
+        if (!$this->hasAspect('language')) {
+            $this->setAspect('language', new LanguageAspect());
+        }
+    }
+
+    /**
+     * Checks if an aspect exists in the context
+     *
+     * @param string $name
+     * @return bool
+     */
+    public function hasAspect(string $name): bool
+    {
+        return isset($this->aspects[$name]);
+    }
+
+    /**
+     * Returns an aspect, if it is set
+     *
+     * @param string $name
+     * @return AspectInterface
+     * @throws AspectNotFoundException
+     */
+    public function getAspect(string $name): AspectInterface
+    {
+        if (!$this->hasAspect($name)) {
+            throw new AspectNotFoundException('No aspect named "' . $name . '" found.', 1527777641);
+        }
+        return $this->aspects[$name];
+    }
+
+    /**
+     * Returns a property from the aspect, but only if the property is found.
+     *
+     * @param string $name
+     * @param string $property
+     * @param mixed $default
+     * @return mixed|null
+     * @throws AspectNotFoundException
+     */
+    public function getPropertyFromAspect(string $name, string $property, $default = null)
+    {
+        if (!$this->hasAspect($name)) {
+            throw new AspectNotFoundException('No aspect named "' . $name . '" found.', 1527777868);
+        }
+        try {
+            return $this->aspects[$name]->get($property);
+        } catch (AspectPropertyNotFoundException $e) {
+            return $default;
+        }
+    }
+
+    /**
+     * Sets an aspect, or overrides an existing aspect if an aspect is already set
+     *
+     * @param string $name
+     * @param AspectInterface $aspect
+     */
+    public function setAspect(string $name, AspectInterface $aspect): void
+    {
+        $this->aspects[$name] = $aspect;
+    }
+}

typo3/sysext/core/Classes/Context/ContextAwareInterface.php

@@ -0,0 +1,23 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Context;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+interface ContextAwareInterface
+{
+    public function setContext(Context $context): void;
+
+    public function getContext(): Context;
+}

typo3/sysext/core/Classes/Context/ContextAwareTrait.php

@@ -0,0 +1,34 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Context;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+trait ContextAwareTrait
+{
+    /**
+     * @var Context
+     */
+    protected $context;
+
+    public function setContext(Context $context): void
+    {
+        $this->context = $context;
+    }
+
+    public function getContext(): Context
+    {
+        return $this->context;
+    }
+}

typo3/sysext/core/Classes/Context/DateTimeAspect.php

@@ -0,0 +1,80 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Context;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Context\Exception\AspectPropertyNotFoundException;
+
+/**
+ * The Aspect is usually available as "date.*" properties in the Context.
+ *
+ * Contains the current time + date + timezone,
+ * and needs a DateTimeImmutable object
+ *
+ * Allowed properties:
+ * - timestamp - unix timestamp number
+ * - timezone - America/Los_Angeles
+ * - iso - datetime as string in ISO 8601 format, e.g. `2004-02-12T15:19:21+00:00`
+ * - full - the DateTimeImmutable object
+ */
+class DateTimeAspect implements AspectInterface
+{
+    /**
+     * @var \DateTimeImmutable
+     */
+    protected $dateTimeObject;
+
+    /**
+     * @param \DateTimeImmutable $dateTimeImmutable
+     */
+    public function __construct(\DateTimeImmutable $dateTimeImmutable)
+    {
+        $this->dateTimeObject = $dateTimeImmutable;
+    }
+
+    /**
+     * Fetch a property of the date time object or the object itself ("full").
+     *
+     * @param string $name
+     * @return \DateTimeImmutable|string
+     * @throws AspectPropertyNotFoundException
+     */
+    public function get(string $name)
+    {
+        switch ($name) {
+            case 'timestamp':
+                return $this->dateTimeObject->format('U');
+            case 'iso':
+                return $this->dateTimeObject->format('c');
+            case 'timezone':
+                return $this->dateTimeObject->format('e');
+            case 'full':
+                return $this->dateTimeObject;
+            case 'accessTime':
+                return $this->dateTimeObject->format('U') - ($this->dateTimeObject->format('U') % 60);
+        }
+        throw new AspectPropertyNotFoundException('Property "' . $name . '" not found in Aspect "' . __CLASS__ . '".', 1527778767);
+    }
+
+    /**
+     * Return the full date time object
+     *
+     * @return \DateTimeImmutable
+     */
+    public function getDateTime(): \DateTimeImmutable
+    {
+        return $this->dateTimeObject;
+    }
+}

typo3/sysext/core/Classes/Context/Exception/AspectNotFoundException.php

@@ -0,0 +1,25 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Context\Exception;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Exception;
+
+/**
+ * Used when an aspect is requested but not found.
+ */
+class AspectNotFoundException extends Exception
+{
+}

typo3/sysext/core/Classes/Context/Exception/AspectPropertyNotFoundException.php

@@ -0,0 +1,25 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Context\Exception;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Exception;
+
+/**
+ * Used when an aspect property is requested but not found.
+ */
+class AspectPropertyNotFoundException extends Exception
+{
+}

typo3/sysext/core/Classes/Context/LanguageAspect.php

@@ -0,0 +1,208 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Context;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Context\Exception\AspectPropertyNotFoundException;
+
+/**
+ * The Aspect is usually available as "language" property, and
+ * can be used to find out the "overlay"/data retrieval strategy.
+ *
+ *
+ * "id" (languageId, int)
+ * - formally known as $TSFE->sys_language_uid
+ * - the requested language of the current page (frontend)
+ * - used in menus and links to generate "links in language with this ID"
+ *
+ * "contentId" (int)
+ * - formally known as $TSFE->sys_language_content
+ * - the language of records to be fetched
+ * - if empty, "languageId" is used.
+ *
+ * "fallbackChain"
+ *  - when "fallback" go with
+ *  - depends what "contentId" value should be set
+ *  - defined in config.sys_language_mode (strict/content_fallback:4,5,stop/ignore?)
+ *  - previously known as $TSFE->sys_language_mode
+ *  - defines "contentId" based on "if the current page is available in this language"
+ *   - "strict"
+ *   - "fallback" if current page is not available, check the fallbackChain"
+ *   - "fallbackAndIgnore"
+ *
+ * "overlayType"
+ * - defines which way the records should be fetched from ($TSFE->sys_language_contentOL and config.sys_language_overlay)
+ * - usually you fetch language 0 and -1, then take the "contentId" and "overlay" them
+ *    - here you have two choices
+ *          1. "on" if there is no overlay, do not render the default language records ("hideNonTranslated")
+ *          2. "mixed" - if there is no overlay, just keep the default language, possibility to have mixed languages - config.sys_language_overlay = 1
+ *          3. "off" - do not do overlay, only fetch records available in the current "contentId" (see above), and do not care about overlays or fallbacks - fallbacks could be an option here, actually that is placed on top
+ *          4. "includeFloating" - on + includeRecordsWithoutDefaultTranslation
+ */
+class LanguageAspect implements AspectInterface
+{
+    /**
+     * @var int
+     */
+    protected $id = 0;
+
+    /**
+     * @var int
+     */
+    protected $contentId = 0;
+
+    /**
+     * @var array
+     */
+    protected $fallbackChain = [];
+
+    /**
+     * @var string
+     */
+    protected $overlayType;
+
+    public const OVERLAYS_OFF = 'off';  // config.sys_language_overlay = 0
+    public const OVERLAYS_MIXED = 'mixed';  // config.sys_language_overlay = 1 (keep the ones that are only available in default language)
+    public const OVERLAYS_ON = 'on';    // "hideNonTranslated"
+    public const OVERLAYS_ON_WITH_FLOATING = 'includeFloating';    // "hideNonTranslated" + records that are only available in polish
+
+    /**
+     * Create the default language
+     *
+     * @param int $id
+     * @param int|null $contentId
+     * @param string $overlayType
+     * @param array $fallbackChain
+     */
+    public function __construct(int $id = 0, int $contentId = null, string $overlayType = self::OVERLAYS_ON_WITH_FLOATING, array $fallbackChain = [])
+    {
+        $this->overlayType = $overlayType;
+        $this->id = $id;
+        $this->contentId = $contentId === null ? $this->id : $contentId;
+        $this->fallbackChain = $fallbackChain;
+    }
+
+    /**
+     * Used language overlay
+     *
+     * @return string
+     */
+    public function getOverlayType(): string
+    {
+        return $this->overlayType;
+    }
+
+    /**
+     * Returns the language ID the current page was requested,
+     * this is relevant when building menus or links to other pages.
+     *
+     * @return int
+     */
+    public function getId(): int
+    {
+        return $this->id;
+    }
+
+    /**
+     * Contains the language UID of the content records that should be overlaid to would be fetched.
+     * This is especially useful when a page requested with language=4 should fall back to showing
+     * content of language=2 (see fallbackChain)
+     *
+     * @return int
+     */
+    public function getContentId(): int
+    {
+        return $this->contentId;
+    }
+
+    public function getFallbackChain(): array
+    {
+        return $this->fallbackChain;
+    }
+
+    /**
+     * Whether overlays should be done
+     *
+     * @return bool
+     */
+    public function doOverlays(): bool
+    {
+        return $this->contentId > 0 && $this->overlayType !== self::OVERLAYS_OFF;
+    }
+
+    /**
+     * Previously known as TSFE->sys_language_mode, here for compatibility reasons
+     *
+     * @return string
+     */
+    public function getLegacyLanguageMode(): string
+    {
+        if ($this->fallbackChain === ['off']) {
+            return '';
+        }
+        if (empty($this->fallbackChain)) {
+            return 'strict';
+        }
+        if ($this->fallbackChain === [-1]) {
+            return 'ignore';
+        }
+        return 'content_fallback';
+    }
+
+    /**
+     * Previously known as TSFE->sys_language_contentOL, here for compatibility reasons
+     *
+     * @return string
+     */
+    public function getLegacyOverlayType(): string
+    {
+        switch ($this->overlayType) {
+            case self::OVERLAYS_ON_WITH_FLOATING:
+            case self::OVERLAYS_ON:
+                return 'hideNonTranslated';
+            case self::OVERLAYS_MIXED:
+                return '1';
+            case self::OVERLAYS_OFF:
+            default:
+                return '0';
+        }
+    }
+
+    /**
+     * Fetch a property.
+     *
+     * @param string $name
+     * @return int|string|array
+     * @throws AspectPropertyNotFoundException
+     */
+    public function get(string $name)
+    {
+        switch ($name) {
+            case 'id':
+                return $this->id;
+            case 'contentId':
+                return $this->contentId;
+            case 'fallbackChain':
+                return $this->fallbackChain;
+            case 'overlayType':
+                return $this->overlayType;
+            case 'legacyLanguageMode':
+                return $this->getLegacyLanguageMode();
+            case 'legacyOverlayType':
+                return $this->getLegacyOverlayType();
+        }
+        throw new AspectPropertyNotFoundException('Property "' . $name . '" not found in Aspect "' . __CLASS__ . '".', 1530448504);
+    }
+}

typo3/sysext/core/Classes/Context/LanguageAspectFactory.php

@@ -0,0 +1,134 @@
+<?php
+declare(strict_types = 1);
+namespace TYPO3\CMS\Core\Context;
+
+/*
+ * This file is part of the TYPO3 CMS project.
+ *
+ * It is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License, either version 2
+ * of the License, or any later version.
+ *
+ * For the full copyright and license information, please read the
+ * LICENSE.txt file that was distributed with this source code.
+ *
+ * The TYPO3 project - inspiring people to share!
+ */
+
+use TYPO3\CMS\Core\Site\Entity\SiteLanguage;
+use TYPO3\CMS\Core\Utility\GeneralUtility;
+
+/**
+ * A simple factory to create a language aspect.
+ */
+class LanguageAspectFactory
+{
+    /**
+     * Create a language aspect based on TypoScript settings, which we know:
+     *
+     * config.sys_language_uid
+     * config.sys_language_mode
+     * config.sys_language_overlay
+     *
+     * @param array $config
+     * @return LanguageAspect
+     */
+    public static function createFromTypoScript(array $config): LanguageAspect
+    {
+        // Get values from TypoScript, if not set before
+        $languageId = (int)($config['sys_language_uid'] ?? 0);
+        $fallbacks = GeneralUtility::trimExplode(';', $config['sys_language_mode'] ?? '');
+        $fallbackMode = null;
+        if (isset($fallbacks[0])) {
+            $fallbackMode = $fallbacks[0];
+        }
+        $fallbackOrder = null;
+        if (isset($fallbacks[1])) {
+            $fallbackOrder = $fallbacks[1];
+        }
+
+        // Page resolving
+        switch ($fallbackMode) {
+            case 'strict':
+                $fallBackOrder = [];
+                break;
+                // Ignore anything if a page cannot be found, and resolve pageId=0 instead.
+            case 'ignore':
+                $fallBackOrder = [-1];
+                break;
+            case 'fallback':
+            case 'content_fallback':
+                if (!empty($fallbackOrder)) {
+                    $fallBackOrder = GeneralUtility::trimExplode(',', $fallbackOrder);
+                    // no strict typing explictly done here
+                    if (!in_array(0, $fallBackOrder) && !in_array('pageNotFound', $fallBackOrder)) {
+                        $fallBackOrder[] = 'pageNotFound';
+                    }
+                } else {
+                    $fallBackOrder = [0];
+                }
+                break;
+            case '':
+                $fallBackOrder = ['off'];
+                break;
+            default:
+                $fallBackOrder = [0];
+        }
+
+        // Content fetching
+        switch ((string)($config['sys_language_overlay'] ?? '')) {
+            case '1':
+                $overlayType = LanguageAspect::OVERLAYS_MIXED;
+                break;
+            case '0':
+                $overlayType = LanguageAspect::OVERLAYS_OFF;
+                break;
+            case 'hideNonTranslated':
+                $overlayType = LanguageAspect::OVERLAYS_ON;
+                break;
+            default:
+                $overlayType = LanguageAspect::OVERLAYS_ON_WITH_FLOATING;
+        }
+
+        return GeneralUtility::makeInstance(LanguageAspect::class, $languageId, $languageId, $overlayType, $fallBackOrder);
+    }
+
+    /**
+     * Site Languages always run with overlays + floating records.
+     *
+     * @param SiteLanguage $language
+     * @return LanguageAspect
+     */
+    public static function createFromSiteLanguage(SiteLanguage $language): LanguageAspect
+    {
+        $languageId = $language->getLanguageId();
+        $fallbackType = $language->getFallbackType();
+        $fallbackOrder = $language->getFallbackLanguageIds();
+        $fallbackOrder[] = 'pageNotFound';
+        switch ($fallbackType) {
+            // Fall back to other language, if the page does not exist in the requested language
+            // But always fetch only records of this specific (available) language
+            case 'free':
+                $overlayType = LanguageAspect::OVERLAYS_OFF;
+                break;
+
+            // Fall back to other language, if the page does not exist in the requested language
+            // Do overlays, and keep the ones that are not translated
+            case 'fallback':
+                $overlayType = LanguageAspect::OVERLAYS_MIXED;
+                break;
+
+            // Same as "fallback" but remove the records that are not translated
+            case 'strict':
+                $overlayType = LanguageAspect::OVERLAYS_ON_WITH_FLOATING;
+                break;
+
+            // Ignore, fallback to default language
+            default:
+                $fallbackOrder = [0];
+                $overlayType = LanguageAspect::OVERLAYS_OFF;
+        }
+
+        return GeneralUtility::makeInstance(LanguageAspect::class, $languageId, $languageId, $overlayType, $fallbackOrder);
+    }
+}