diff options
author | Pierre Schmitz <pierre@archlinux.de> | 2013-01-18 16:46:04 +0100 |
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committer | Pierre Schmitz <pierre@archlinux.de> | 2013-01-18 16:46:04 +0100 |
commit | 63601400e476c6cf43d985f3e7b9864681695ed4 (patch) | |
tree | f7846203a952e38aaf66989d0a4702779f549962 /includes/filebackend/lockmanager/LSLockManager.php | |
parent | 8ff01378c9e0207f9169b81966a51def645b6a51 (diff) |
Update to MediaWiki 1.20.2
this update includes:
* adjusted Arch Linux skin
* updated FluxBBAuthPlugin
* patch for https://bugzilla.wikimedia.org/show_bug.cgi?id=44024
Diffstat (limited to 'includes/filebackend/lockmanager/LSLockManager.php')
-rw-r--r-- | includes/filebackend/lockmanager/LSLockManager.php | 218 |
1 files changed, 218 insertions, 0 deletions
diff --git a/includes/filebackend/lockmanager/LSLockManager.php b/includes/filebackend/lockmanager/LSLockManager.php new file mode 100644 index 00000000..89428182 --- /dev/null +++ b/includes/filebackend/lockmanager/LSLockManager.php @@ -0,0 +1,218 @@ +<?php +/** + * Version of LockManager based on using lock daemon servers. + * + * 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 + */ + +/** + * Manage locks using a lock daemon server. + * + * Version of LockManager based on using lock daemon servers. + * This is meant for multi-wiki systems that may share files. + * All locks are non-blocking, which avoids deadlocks. + * + * All lock requests for a resource, identified by a hash string, will map + * to one bucket. Each bucket maps to one or several peer servers, each + * running LockServerDaemon.php, listening on a designated TCP port. + * A majority of peers must agree for a lock to be acquired. + * + * @ingroup LockManager + * @since 1.19 + */ +class LSLockManager extends QuorumLockManager { + /** @var Array Mapping of lock types to the type actually used */ + protected $lockTypeMap = array( + self::LOCK_SH => self::LOCK_SH, + self::LOCK_UW => self::LOCK_SH, + self::LOCK_EX => self::LOCK_EX + ); + + /** @var Array Map of server names to server config */ + protected $lockServers; // (server name => server config array) + + /** @var Array Map Server connections (server name => resource) */ + protected $conns = array(); + + protected $connTimeout; // float number of seconds + protected $session = ''; // random SHA-1 string + + /** + * Construct a new instance from configuration. + * + * $config paramaters include: + * - lockServers : Associative array of server names to configuration. + * Configuration is an associative array that includes: + * - host : IP address/hostname + * - port : TCP port + * - authKey : Secret string the lock server uses + * - srvsByBucket : Array of 1-16 consecutive integer keys, starting from 0, + * each having an odd-numbered list of server names (peers) as values. + * - connTimeout : Lock server connection attempt timeout. [optional] + * + * @param Array $config + */ + public function __construct( array $config ) { + parent::__construct( $config ); + + $this->lockServers = $config['lockServers']; + // Sanitize srvsByBucket config to prevent PHP errors + $this->srvsByBucket = array_filter( $config['srvsByBucket'], 'is_array' ); + $this->srvsByBucket = array_values( $this->srvsByBucket ); // consecutive + + if ( isset( $config['connTimeout'] ) ) { + $this->connTimeout = $config['connTimeout']; + } else { + $this->connTimeout = 3; // use some sane amount + } + + $this->session = wfRandomString( 32 ); // 128 bits + } + + /** + * @see QuorumLockManager::getLocksOnServer() + * @return Status + */ + protected function getLocksOnServer( $lockSrv, array $paths, $type ) { + $status = Status::newGood(); + + // Send out the command and get the response... + $type = ( $type == self::LOCK_SH ) ? 'SH' : 'EX'; + $keys = array_unique( array_map( 'LockManager::sha1Base36', $paths ) ); + $response = $this->sendCommand( $lockSrv, 'ACQUIRE', $type, $keys ); + + if ( $response !== 'ACQUIRED' ) { + foreach ( $paths as $path ) { + $status->fatal( 'lockmanager-fail-acquirelock', $path ); + } + } + + return $status; + } + + /** + * @see QuorumLockManager::freeLocksOnServer() + * @return Status + */ + protected function freeLocksOnServer( $lockSrv, array $paths, $type ) { + $status = Status::newGood(); + + // Send out the command and get the response... + $type = ( $type == self::LOCK_SH ) ? 'SH' : 'EX'; + $keys = array_unique( array_map( 'LockManager::sha1Base36', $paths ) ); + $response = $this->sendCommand( $lockSrv, 'RELEASE', $type, $keys ); + + if ( $response !== 'RELEASED' ) { + foreach ( $paths as $path ) { + $status->fatal( 'lockmanager-fail-releaselock', $path ); + } + } + + return $status; + } + + /** + * @see QuorumLockManager::releaseAllLocks() + * @return Status + */ + protected function releaseAllLocks() { + $status = Status::newGood(); + + foreach ( $this->conns as $lockSrv => $conn ) { + $response = $this->sendCommand( $lockSrv, 'RELEASE_ALL', '', array() ); + if ( $response !== 'RELEASED_ALL' ) { + $status->fatal( 'lockmanager-fail-svr-release', $lockSrv ); + } + } + + return $status; + } + + /** + * @see QuorumLockManager::isServerUp() + * @return bool + */ + protected function isServerUp( $lockSrv ) { + return (bool)$this->getConnection( $lockSrv ); + } + + /** + * Send a command and get back the response + * + * @param $lockSrv string + * @param $action string + * @param $type string + * @param $values Array + * @return string|bool + */ + protected function sendCommand( $lockSrv, $action, $type, $values ) { + $conn = $this->getConnection( $lockSrv ); + if ( !$conn ) { + return false; // no connection + } + $authKey = $this->lockServers[$lockSrv]['authKey']; + // Build of the command as a flat string... + $values = implode( '|', $values ); + $key = sha1( $this->session . $action . $type . $values . $authKey ); + // Send out the command... + if ( fwrite( $conn, "{$this->session}:$key:$action:$type:$values\n" ) === false ) { + return false; + } + // Get the response... + $response = fgets( $conn ); + if ( $response === false ) { + return false; + } + return trim( $response ); + } + + /** + * Get (or reuse) a connection to a lock server + * + * @param $lockSrv string + * @return resource + */ + protected function getConnection( $lockSrv ) { + if ( !isset( $this->conns[$lockSrv] ) ) { + $cfg = $this->lockServers[$lockSrv]; + wfSuppressWarnings(); + $errno = $errstr = ''; + $conn = fsockopen( $cfg['host'], $cfg['port'], $errno, $errstr, $this->connTimeout ); + wfRestoreWarnings(); + if ( $conn === false ) { + return null; + } + $sec = floor( $this->connTimeout ); + $usec = floor( ( $this->connTimeout - floor( $this->connTimeout ) ) * 1e6 ); + stream_set_timeout( $conn, $sec, $usec ); + $this->conns[$lockSrv] = $conn; + } + return $this->conns[$lockSrv]; + } + + /** + * Make sure remaining locks get cleared for sanity + */ + function __destruct() { + $this->releaseAllLocks(); + foreach ( $this->conns as $conn ) { + fclose( $conn ); + } + } +} |