diff options
Diffstat (limited to 'www/wiki/includes/libs/lockmanager/ScopedLock.php')
-rw-r--r-- | www/wiki/includes/libs/lockmanager/ScopedLock.php | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/www/wiki/includes/libs/lockmanager/ScopedLock.php b/www/wiki/includes/libs/lockmanager/ScopedLock.php new file mode 100644 index 00000000..6261335e --- /dev/null +++ b/www/wiki/includes/libs/lockmanager/ScopedLock.php @@ -0,0 +1,106 @@ +<?php +/** + * Resource locking handling. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License along + * with this program; if not, write to the Free Software Foundation, Inc., + * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + * http://www.gnu.org/copyleft/gpl.html + * + * @file + * @ingroup LockManager + */ + +/** + * Self-releasing locks + * + * LockManager helper class to handle scoped locks, which + * release when an object is destroyed or goes out of scope. + * + * @ingroup LockManager + * @since 1.19 + */ +class ScopedLock { + /** @var LockManager */ + protected $manager; + + /** @var StatusValue */ + protected $status; + + /** @var array Map of lock types to resource paths */ + protected $pathsByType; + + /** + * @param LockManager $manager + * @param array $pathsByType Map of lock types to path lists + * @param StatusValue $status + */ + protected function __construct( + LockManager $manager, array $pathsByType, StatusValue $status + ) { + $this->manager = $manager; + $this->pathsByType = $pathsByType; + $this->status = $status; + } + + /** + * Get a ScopedLock object representing a lock on resource paths. + * Any locks are released once this object goes out of scope. + * The StatusValue object is updated with any errors or warnings. + * + * @param LockManager $manager + * @param array $paths List of storage paths or map of lock types to path lists + * @param int|string $type LockManager::LOCK_* constant or "mixed" and $paths + * can be a map of types to paths (since 1.22). Otherwise $type should be an + * integer and $paths should be a list of paths. + * @param StatusValue $status + * @param int $timeout Timeout in seconds (0 means non-blocking) (since 1.22) + * @return ScopedLock|null Returns null on failure + */ + public static function factory( + LockManager $manager, array $paths, $type, StatusValue $status, $timeout = 0 + ) { + $pathsByType = is_int( $type ) ? [ $type => $paths ] : $paths; + $lockStatus = $manager->lockByType( $pathsByType, $timeout ); + $status->merge( $lockStatus ); + if ( $lockStatus->isOK() ) { + return new self( $manager, $pathsByType, $status ); + } + + return null; + } + + /** + * Release a scoped lock and set any errors in the attatched StatusValue object. + * This is useful for early release of locks before function scope is destroyed. + * This is the same as setting the lock object to null. + * + * @param ScopedLock &$lock + * @since 1.21 + */ + public static function release( ScopedLock &$lock = null ) { + $lock = null; + } + + /** + * Release the locks when this goes out of scope + */ + function __destruct() { + $wasOk = $this->status->isOK(); + $this->status->merge( $this->manager->unlockByType( $this->pathsByType ) ); + if ( $wasOk ) { + // Make sure StatusValue is OK, despite any unlockFiles() fatals + $this->status->setResult( true, $this->status->value ); + } + } +} |