LockManager.php

Go to the documentation of this file.

<?php
abstract class LockManager {
        protected $lockTypeMap = array(
                self::LOCK_SH => self::LOCK_SH,
                self::LOCK_UW => self::LOCK_EX, // subclasses may use self::LOCK_SH
                self::LOCK_EX => self::LOCK_EX
        );

        protected $locksHeld = array();

        /* Lock types; stronger locks have higher values */
        const LOCK_SH = 1; // shared lock (for reads)
        const LOCK_UW = 2; // shared lock (for reads used to write elsewhere)
        const LOCK_EX = 3; // exclusive lock (for writes)

        public function __construct( array $config ) {}

        final public function lock( array $paths, $type = self::LOCK_EX ) {
                return $this->doLock( array_unique( $paths ), $this->lockTypeMap[$type] );
        }

        final public function unlock( array $paths, $type = self::LOCK_EX ) {
                return $this->doUnlock( array_unique( $paths ), $this->lockTypeMap[$type] );
        }

        final protected static function sha1Base36( $path ) {
                return wfBaseConvert( sha1( $path ), 16, 36, 31 );
        }

        abstract protected function doLock( array $paths, $type );

        abstract protected function doUnlock( array $paths, $type );
}

class ScopedLock {
        protected $manager;
        protected $status;
        protected $paths;

        protected $type; // integer lock type

        protected function __construct(
                LockManager $manager, array $paths, $type, Status $status
        ) {
                $this->manager = $manager;
                $this->paths = $paths;
                $this->status = $status;
                $this->type = $type;
        }

        protected function __clone() {}

        public static function factory(
                LockManager $manager, array $paths, $type, Status $status
        ) {
                $lockStatus = $manager->lock( $paths, $type );
                $status->merge( $lockStatus );
                if ( $lockStatus->isOK() ) {
                        return new self( $manager, $paths, $type, $status );
                }
                return null;
        }

        function __destruct() {
                $wasOk = $this->status->isOK();
                $this->status->merge( $this->manager->unlock( $this->paths, $this->type ) );
                if ( $wasOk ) {
                        // Make sure status is OK, despite any unlockFiles() fatals
                        $this->status->setResult( true, $this->status->value );
                }
        }
}

class NullLockManager extends LockManager {
        protected function doLock( array $paths, $type ) {
                return Status::newGood();
        }

        protected function doUnlock( array $paths, $type ) {
                return Status::newGood();
        }
}