<?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.
* A majority of peers must agree for a lock to be acquired.
*
* @ingroup LockManager
+ * @since 1.19
*/
class LSLockManager extends LockManager {
/** @var Array Mapping of lock types to the type actually used */
/** @var Array Map of bucket indexes to peer server lists */
protected $srvsByBucket; // (bucket index => (lsrv1, lsrv2, ...))
- /** @var Array Map of (locked key => lock type => count) */
- protected $locksHeld = array();
/** @var Array Map Server connections (server name => resource) */
protected $conns = array();
/**
* Construct a new instance from configuration.
+ *
* $config paramaters include:
* 'lockServers' : Associative array of server names to configuration.
* Configuration is an associative array that includes:
* @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->session = wfBaseConvert( sha1( $this->session ), 16, 36, 31 );
}
- protected function doLock( array $keys, $type ) {
+ /**
+ * @see LockManager::doLock()
+ * @param $paths array
+ * @param $type int
+ * @return Status
+ */
+ protected function doLock( array $paths, $type ) {
$status = Status::newGood();
- $keysToLock = array();
+ $pathsToLock = array();
// Get locks that need to be acquired (buckets => locks)...
- foreach ( $keys as $key ) {
- if ( isset( $this->locksHeld[$key][$type] ) ) {
- ++$this->locksHeld[$key][$type];
- } elseif ( isset( $this->locksHeld[$key][self::LOCK_EX] ) ) {
- $this->locksHeld[$key][$type] = 1;
+ foreach ( $paths as $path ) {
+ if ( isset( $this->locksHeld[$path][$type] ) ) {
+ ++$this->locksHeld[$path][$type];
+ } elseif ( isset( $this->locksHeld[$path][self::LOCK_EX] ) ) {
+ $this->locksHeld[$path][$type] = 1;
} else {
- $bucket = $this->getBucketFromKey( $key );
- $keysToLock[$bucket][] = $key;
+ $bucket = $this->getBucketFromKey( $path );
+ $pathsToLock[$bucket][] = $path;
}
}
- $lockedKeys = array(); // files locked in this attempt
+ $lockedPaths = array(); // files locked in this attempt
// Attempt to acquire these locks...
- foreach ( $keysToLock as $bucket => $keys ) {
+ foreach ( $pathsToLock as $bucket => $paths ) {
// Try to acquire the locks for this bucket
- $res = $this->doLockingRequestAll( $bucket, $keys, $type );
+ $res = $this->doLockingRequestAll( $bucket, $paths, $type );
if ( $res === 'cantacquire' ) {
// Resources already locked by another process.
// Abort and unlock everything we just locked.
- $status->fatal( 'lockmanager-fail-acquirelocks', implode( ', ', $keys ) );
- $status->merge( $this->doUnlock( $lockedKeys, $type ) );
+ foreach ( $paths as $path ) {
+ $status->fatal( 'lockmanager-fail-acquirelock', $path );
+ }
+ $status->merge( $this->doUnlock( $lockedPaths, $type ) );
return $status;
} elseif ( $res !== true ) {
// Couldn't contact any servers for this bucket.
// Abort and unlock everything we just locked.
- $status->fatal( 'lockmanager-fail-acquirelocks', implode( ', ', $keys ) );
- $status->merge( $this->doUnlock( $lockedKeys, $type ) );
+ foreach ( $paths as $path ) {
+ $status->fatal( 'lockmanager-fail-acquirelock', $path );
+ }
+ $status->merge( $this->doUnlock( $lockedPaths, $type ) );
return $status;
}
// Record these locks as active
- foreach ( $keys as $key ) {
- $this->locksHeld[$key][$type] = 1; // locked
+ foreach ( $paths as $path ) {
+ $this->locksHeld[$path][$type] = 1; // locked
}
// Keep track of what locks were made in this attempt
- $lockedKeys = array_merge( $lockedKeys, $keys );
+ $lockedPaths = array_merge( $lockedPaths, $paths );
}
return $status;
}
- protected function doUnlock( array $keys, $type ) {
+ /**
+ * @see LockManager::doUnlock()
+ * @param $paths array
+ * @param $type int
+ * @return Status
+ */
+ protected function doUnlock( array $paths, $type ) {
$status = Status::newGood();
- foreach ( $keys as $key ) {
- if ( !isset( $this->locksHeld[$key] ) ) {
- $status->warning( 'lockmanager-notlocked', $key );
- } elseif ( !isset( $this->locksHeld[$key][$type] ) ) {
- $status->warning( 'lockmanager-notlocked', $key );
+ foreach ( $paths as $path ) {
+ if ( !isset( $this->locksHeld[$path] ) ) {
+ $status->warning( 'lockmanager-notlocked', $path );
+ } elseif ( !isset( $this->locksHeld[$path][$type] ) ) {
+ $status->warning( 'lockmanager-notlocked', $path );
} else {
- --$this->locksHeld[$key][$type];
- if ( $this->locksHeld[$key][$type] <= 0 ) {
- unset( $this->locksHeld[$key][$type] );
+ --$this->locksHeld[$path][$type];
+ if ( $this->locksHeld[$path][$type] <= 0 ) {
+ unset( $this->locksHeld[$path][$type] );
}
- if ( !count( $this->locksHeld[$key] ) ) {
- unset( $this->locksHeld[$key] ); // no SH or EX locks left for key
+ if ( !count( $this->locksHeld[$path] ) ) {
+ unset( $this->locksHeld[$path] ); // no SH or EX locks left for key
}
}
}
}
/**
- * Get a connection to a lock server and acquire locks on $keys
+ * Get a connection to a lock server and acquire locks on $paths
*
* @param $lockSrv string
- * @param $keys Array
+ * @param $paths Array
* @param $type integer LockManager::LOCK_EX or LockManager::LOCK_SH
* @return bool Resources able to be locked
*/
- protected function doLockingRequest( $lockSrv, array $keys, $type ) {
+ protected function doLockingRequest( $lockSrv, array $paths, $type ) {
if ( $type == self::LOCK_SH ) { // reader locks
$type = 'SH';
} elseif ( $type == self::LOCK_EX ) { // writer locks
}
// Send out the command and get the response...
+ $keys = array_unique( array_map( 'LockManager::sha1Base36', $paths ) );
$response = $this->sendCommand( $lockSrv, 'ACQUIRE', $type, $keys );
return ( $response === 'ACQUIRED' );
* @param $action string
* @param $type string
* @param $values Array
- * @return string|false
+ * @return string|bool
*/
protected function sendCommand( $lockSrv, $action, $type, $values ) {
$conn = $this->getConnection( $lockSrv );
* Attempt to acquire locks with the peers for a bucket
*
* @param $bucket integer
- * @param $keys Array List of resource keys to lock
+ * @param $paths Array List of resource keys to lock
* @param $type integer LockManager::LOCK_EX or LockManager::LOCK_SH
* @return bool|string One of (true, 'cantacquire', 'srverrors')
*/
- protected function doLockingRequestAll( $bucket, array $keys, $type ) {
+ protected function doLockingRequestAll( $bucket, array $paths, $type ) {
$yesVotes = 0; // locks made on trustable servers
$votesLeft = count( $this->srvsByBucket[$bucket] ); // remaining peers
$quorum = floor( $votesLeft/2 + 1 ); // simple majority
// Get votes for each peer, in order, until we have enough...
- foreach ( $this->srvsByBucket[$bucket] as $index => $lockSrv ) {
+ foreach ( $this->srvsByBucket[$bucket] as $lockSrv ) {
// Attempt to acquire the lock on this peer
- if ( !$this->doLockingRequest( $lockSrv, $keys, $type ) ) {
+ if ( !$this->doLockingRequest( $lockSrv, $paths, $type ) ) {
return 'cantacquire'; // vetoed; resource locked
}
++$yesVotes; // success for this peer
if ( $yesVotes >= $quorum ) {
return true; // lock obtained
}
- $votesLeft--;
+ --$votesLeft;
$votesNeeded = $quorum - $yesVotes;
if ( $votesNeeded > $votesLeft ) {
// In "trust cache" mode we don't have to meet the quorum
}
/**
- * Get the bucket for lock key
+ * Get the bucket for resource path.
+ * This should avoid throwing any exceptions.
*
- * @param $key string (31 char hex key)
+ * @param $path string
* @return integer
*/
- protected function getBucketFromKey( $key ) {
- $prefix = substr( $key, 0, 2 ); // first 2 hex chars (8 bits)
+ protected function getBucketFromKey( $path ) {
+ $prefix = substr( sha1( $path ), 0, 2 ); // first 2 hex chars (8 bits)
return intval( base_convert( $prefix, 16, 10 ) ) % count( $this->srvsByBucket );
}
*/
function __destruct() {
$this->releaseLocks();
- foreach ( $this->conns as $lockSrv => $conn ) {
+ foreach ( $this->conns as $conn ) {
fclose( $conn );
}
}
dépôts / lhc / web / wiklou.git / blobdiff