LSLockManager.php

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<?php
class LSLockManager extends QuorumLockManager {
        protected $lockTypeMap = array(
                self::LOCK_SH => self::LOCK_SH,
                self::LOCK_UW => self::LOCK_SH,
                self::LOCK_EX => self::LOCK_EX
        );

        protected $lockServers; // (server name => server config array)

        protected $conns = array();

        protected $connTimeout; // float number of seconds
        protected $session = ''; // random SHA-1 string

        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
        }

        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;
        }

        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;
        }

        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;
        }

        protected function isServerUp( $lockSrv ) {
                return (bool)$this->getConnection( $lockSrv );
        }

        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 );
        }

        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];
        }

        function __destruct() {
                $this->releaseAllLocks();
                foreach ( $this->conns as $conn ) {
                        fclose( $conn );
                }
        }
}