diff options
Diffstat (limited to 'includes/objectcache/MemcachedClient.php')
| -rw-r--r-- | includes/objectcache/MemcachedClient.php | 281 |
1 files changed, 174 insertions, 107 deletions
diff --git a/includes/objectcache/MemcachedClient.php b/includes/objectcache/MemcachedClient.php index 868ad69f..536ba6ea 100644 --- a/includes/objectcache/MemcachedClient.php +++ b/includes/objectcache/MemcachedClient.php @@ -1,5 +1,7 @@ <?php /** + * Memcached client for PHP. + * * +---------------------------------------------------------------------------+ * | memcached client, PHP | * +---------------------------------------------------------------------------+ @@ -257,7 +259,7 @@ class MWMemcached { $this->_host_dead = array(); $this->_timeout_seconds = 0; - $this->_timeout_microseconds = isset( $args['timeout'] ) ? $args['timeout'] : 100000; + $this->_timeout_microseconds = isset( $args['timeout'] ) ? $args['timeout'] : 500000; $this->_connect_timeout = isset( $args['connect_timeout'] ) ? $args['connect_timeout'] : 0.1; $this->_connect_attempts = 2; @@ -328,27 +330,36 @@ class MWMemcached { $this->stats['delete'] = 1; } $cmd = "delete $key $time\r\n"; - if( !$this->_safe_fwrite( $sock, $cmd, strlen( $cmd ) ) ) { - $this->_dead_sock( $sock ); + if( !$this->_fwrite( $sock, $cmd ) ) { return false; } - $res = trim( fgets( $sock ) ); + $res = $this->_fgets( $sock ); if ( $this->_debug ) { $this->_debugprint( sprintf( "MemCache: delete %s (%s)\n", $key, $res ) ); } - if ( $res == "DELETED" ) { + if ( $res == "DELETED" || $res == "NOT_FOUND" ) { return true; } + return false; } + /** + * @param $key + * @param $timeout int + * @return bool + */ public function lock( $key, $timeout = 0 ) { /* stub */ return true; } + /** + * @param $key + * @return bool + */ public function unlock( $key ) { /* stub */ return true; @@ -427,8 +438,7 @@ class MWMemcached { } $cmd = "get $key\r\n"; - if ( !$this->_safe_fwrite( $sock, $cmd, strlen( $cmd ) ) ) { - $this->_dead_sock( $sock ); + if ( !$this->_fwrite( $sock, $cmd ) ) { wfProfileOut( __METHOD__ ); return false; } @@ -471,7 +481,7 @@ class MWMemcached { $this->stats['get_multi'] = 1; } $sock_keys = array(); - + $socks = array(); foreach ( $keys as $key ) { $sock = $this->get_sock( $key ); if ( !is_resource( $sock ) ) { @@ -479,24 +489,23 @@ class MWMemcached { } $key = is_array( $key ) ? $key[1] : $key; if ( !isset( $sock_keys[$sock] ) ) { - $sock_keys[$sock] = array(); + $sock_keys[ intval( $sock ) ] = array(); $socks[] = $sock; } - $sock_keys[$sock][] = $key; + $sock_keys[ intval( $sock ) ][] = $key; } + $gather = array(); // Send out the requests foreach ( $socks as $sock ) { $cmd = 'get'; - foreach ( $sock_keys[$sock] as $key ) { + foreach ( $sock_keys[ intval( $sock ) ] as $key ) { $cmd .= ' ' . $key; } $cmd .= "\r\n"; - if ( $this->_safe_fwrite( $sock, $cmd, strlen( $cmd ) ) ) { + if ( $this->_fwrite( $sock, $cmd ) ) { $gather[] = $sock; - } else { - $this->_dead_sock( $sock ); } } @@ -559,12 +568,6 @@ class MWMemcached { * Passes through $cmd to the memcache server connected by $sock; returns * output as an array (null array if no output) * - * NOTE: due to a possible bug in how PHP reads while using fgets(), each - * line may not be terminated by a \r\n. More specifically, my testing - * has shown that, on FreeBSD at least, each line is terminated only - * with a \n. This is with the PHP flag auto_detect_line_endings set - * to falase (the default). - * * @param $sock Resource: socket to send command on * @param $cmd String: command to run * @@ -575,12 +578,13 @@ class MWMemcached { return array(); } - if ( !$this->_safe_fwrite( $sock, $cmd, strlen( $cmd ) ) ) { + if ( !$this->_fwrite( $sock, $cmd ) ) { return array(); } + $ret = array(); while ( true ) { - $res = fgets( $sock ); + $res = $this->_fgets( $sock ); $ret[] = $res; if ( preg_match( '/^END/', $res ) ) { break; @@ -717,15 +721,19 @@ class MWMemcached { wfRestoreWarnings(); } if ( !$sock ) { - if ( $this->_debug ) { - $this->_debugprint( "Error connecting to $host: $errstr\n" ); - } + $this->_error_log( "Error connecting to $host: $errstr\n" ); + $this->_dead_host( $host ); return false; } // Initialise timeout stream_set_timeout( $sock, $this->_timeout_seconds, $this->_timeout_microseconds ); + // If the connection was persistent, flush the read buffer in case there + // was a previous incomplete request on this connection + if ( $this->_persistent ) { + $this->_flush_read_buffer( $sock ); + } return true; } @@ -744,6 +752,9 @@ class MWMemcached { $this->_dead_host( $host ); } + /** + * @param $host + */ function _dead_host( $host ) { $parts = explode( ':', $host ); $ip = $parts[0]; @@ -769,13 +780,12 @@ class MWMemcached { } if ( $this->_single_sock !== null ) { - $this->_flush_read_buffer( $this->_single_sock ); return $this->sock_to_host( $this->_single_sock ); } $hv = is_array( $key ) ? intval( $key[0] ) : $this->_hashfunc( $key ); - if ( $this->_buckets === null ) { + $bu = array(); foreach ( $this->_servers as $v ) { if ( is_array( $v ) ) { for( $i = 0; $i < $v[1]; $i++ ) { @@ -794,7 +804,6 @@ class MWMemcached { $host = $this->_buckets[$hv % $this->_bucketcount]; $sock = $this->sock_to_host( $host ); if ( is_resource( $sock ) ) { - $this->_flush_read_buffer( $sock ); return $sock; } $hv = $this->_hashfunc( $hv . $realkey ); @@ -815,7 +824,7 @@ class MWMemcached { * @access private */ function _hashfunc( $key ) { - # Hash function must on [0,0x7ffffff] + # Hash function must be in [0,0x7ffffff] # We take the first 31 bits of the MD5 hash, which unlike the hash # function used in a previous version of this client, works return hexdec( substr( md5( $key ), 0, 8 ) ) & 0x7fffffff; @@ -850,11 +859,11 @@ class MWMemcached { } else { $this->stats[$cmd] = 1; } - if ( !$this->_safe_fwrite( $sock, "$cmd $key $amt\r\n" ) ) { - return $this->_dead_sock( $sock ); + if ( !$this->_fwrite( $sock, "$cmd $key $amt\r\n" ) ) { + return null; } - $line = fgets( $sock ); + $line = $this->_fgets( $sock ); $match = array(); if ( !preg_match( '/^(\d+)/', $line, $match ) ) { return null; @@ -870,58 +879,42 @@ class MWMemcached { * * @param $sock Resource: socket to read from * @param $ret Array: returned values + * @return boolean True for success, false for failure * * @access private */ function _load_items( $sock, &$ret ) { while ( 1 ) { - $decl = fgets( $sock ); - if ( $decl == "END\r\n" ) { + $decl = $this->_fgets( $sock ); + if( $decl === false ) { + return false; + } elseif ( $decl == "END" ) { return true; - } elseif ( preg_match( '/^VALUE (\S+) (\d+) (\d+)\r\n$/', $decl, $match ) ) { + } elseif ( preg_match( '/^VALUE (\S+) (\d+) (\d+)$/', $decl, $match ) ) { list( $rkey, $flags, $len ) = array( $match[1], $match[2], $match[3] ); - $bneed = $len + 2; - $offset = 0; - - while ( $bneed > 0 ) { - $data = fread( $sock, $bneed ); - $n = strlen( $data ); - if ( $n == 0 ) { - break; - } - $offset += $n; - $bneed -= $n; - if ( isset( $ret[$rkey] ) ) { - $ret[$rkey] .= $data; - } else { - $ret[$rkey] = $data; - } + $data = $this->_fread( $sock, $len + 2 ); + if ( $data === false ) { + return false; } - - if ( $offset != $len + 2 ) { - // Something is borked! - if ( $this->_debug ) { - $this->_debugprint( sprintf( "Something is borked! key %s expecting %d got %d length\n", $rkey, $len + 2, $offset ) ); - } - - unset( $ret[$rkey] ); - $this->_close_sock( $sock ); + if ( substr( $data, -2 ) !== "\r\n" ) { + $this->_handle_error( $sock, + 'line ending missing from data block from $1' ); return false; } + $data = substr( $data, 0, -2 ); + $ret[$rkey] = $data; if ( $this->_have_zlib && $flags & self::COMPRESSED ) { $ret[$rkey] = gzuncompress( $ret[$rkey] ); } - $ret[$rkey] = rtrim( $ret[$rkey] ); - if ( $flags & self::SERIALIZED ) { $ret[$rkey] = unserialize( $ret[$rkey] ); } } else { - $this->_debugprint( "Error parsing memcached response\n" ); - return 0; + $this->_handle_error( $sock, 'Error parsing response from $1' ); + return false; } } } @@ -960,15 +953,6 @@ class MWMemcached { $this->stats[$cmd] = 1; } - // TTLs higher than 30 days will be detected as absolute TTLs - // (UNIX timestamps), and will result in the cache entry being - // discarded immediately because the expiry is in the past. - // Clamp expiries >30d at 30d, unless they're >=1e9 in which - // case they are likely to really be absolute (1e9 = 2011-09-09) - if ( $exp > 2592000 && $exp < 1000000000 ) { - $exp = 2592000; - } - $flags = 0; if ( !is_scalar( $val ) ) { @@ -996,11 +980,11 @@ class MWMemcached { $flags |= self::COMPRESSED; } } - if ( !$this->_safe_fwrite( $sock, "$cmd $key $flags $exp $len\r\n$val\r\n" ) ) { - return $this->_dead_sock( $sock ); + if ( !$this->_fwrite( $sock, "$cmd $key $flags $exp $len\r\n$val\r\n" ) ) { + return false; } - $line = trim( fgets( $sock ) ); + $line = $this->_fgets( $sock ); if ( $this->_debug ) { $this->_debugprint( sprintf( "%s %s (%s)\n", $cmd, $key, $line ) ); @@ -1037,7 +1021,7 @@ class MWMemcached { } if ( !$this->_connect_sock( $sock, $host ) ) { - return $this->_dead_host( $host ); + return null; } // Do not buffer writes @@ -1048,49 +1032,136 @@ class MWMemcached { return $this->_cache_sock[$host]; } - function _debugprint( $str ) { - print( $str ); + /** + * @param $text string + */ + function _debugprint( $text ) { + global $wgDebugLogGroups; + if( !isset( $wgDebugLogGroups['memcached'] ) ) { + # Prefix message since it will end up in main debug log file + $text = "memcached: $text"; + } + wfDebugLog( 'memcached', $text ); + } + + /** + * @param $text string + */ + function _error_log( $text ) { + wfDebugLog( 'memcached-serious', "Memcached error: $text" ); } /** - * Write to a stream, timing out after the correct amount of time + * Write to a stream. If there is an error, mark the socket dead. * - * @return Boolean: false on failure, true on success + * @param $sock The socket + * @param $buf The string to write + * @return bool True on success, false on failure */ - /* - function _safe_fwrite( $f, $buf, $len = false ) { - stream_set_blocking( $f, 0 ); + function _fwrite( $sock, $buf ) { + $bytesWritten = 0; + $bufSize = strlen( $buf ); + while ( $bytesWritten < $bufSize ) { + $result = fwrite( $sock, $buf ); + $data = stream_get_meta_data( $sock ); + if ( $data['timed_out'] ) { + $this->_handle_error( $sock, 'timeout writing to $1' ); + return false; + } + // Contrary to the documentation, fwrite() returns zero on error in PHP 5.3. + if ( $result === false || $result === 0 ) { + $this->_handle_error( $sock, 'error writing to $1' ); + return false; + } + $bytesWritten += $result; + } - if ( $len === false ) { - wfDebug( "Writing " . strlen( $buf ) . " bytes\n" ); - $bytesWritten = fwrite( $f, $buf ); - } else { - wfDebug( "Writing $len bytes\n" ); - $bytesWritten = fwrite( $f, $buf, $len ); + return true; + } + + /** + * Handle an I/O error. Mark the socket dead and log an error. + */ + function _handle_error( $sock, $msg ) { + $peer = stream_socket_get_name( $sock, true /** remote **/ ); + if ( strval( $peer ) === '' ) { + $peer = array_search( $sock, $this->_cache_sock ); + if ( $peer === false ) { + $peer = '[unknown host]'; + } } - $n = stream_select( $r = null, $w = array( $f ), $e = null, 10, 0 ); - # $this->_timeout_seconds, $this->_timeout_microseconds ); + $msg = str_replace( '$1', $peer, $msg ); + $this->_error_log( "$msg\n" ); + $this->_dead_sock( $sock ); + } - wfDebug( "stream_select returned $n\n" ); - stream_set_blocking( $f, 1 ); - return $n == 1; - return $bytesWritten; - }*/ + /** + * Read the specified number of bytes from a stream. If there is an error, + * mark the socket dead. + * + * @param $sock The socket + * @param $len The number of bytes to read + * @return The string on success, false on failure. + */ + function _fread( $sock, $len ) { + $buf = ''; + while ( $len > 0 ) { + $result = fread( $sock, $len ); + $data = stream_get_meta_data( $sock ); + if ( $data['timed_out'] ) { + $this->_handle_error( $sock, 'timeout reading from $1' ); + return false; + } + if ( $result === false ) { + $this->_handle_error( $sock, 'error reading buffer from $1' ); + return false; + } + if ( $result === '' ) { + // This will happen if the remote end of the socket is shut down + $this->_handle_error( $sock, 'unexpected end of file reading from $1' ); + return false; + } + $len -= strlen( $result ); + $buf .= $result; + } + return $buf; + } /** - * Original behaviour + * Read a line from a stream. If there is an error, mark the socket dead. + * The \r\n line ending is stripped from the response. + * + * @param $sock The socket + * @return The string on success, false on failure */ - function _safe_fwrite( $f, $buf, $len = false ) { - if ( $len === false ) { - $bytesWritten = fwrite( $f, $buf ); + function _fgets( $sock ) { + $result = fgets( $sock ); + // fgets() may return a partial line if there is a select timeout after + // a successful recv(), so we have to check for a timeout even if we + // got a string response. + $data = stream_get_meta_data( $sock ); + if ( $data['timed_out'] ) { + $this->_handle_error( $sock, 'timeout reading line from $1' ); + return false; + } + if ( $result === false ) { + $this->_handle_error( $sock, 'error reading line from $1' ); + return false; + } + if ( substr( $result, -2 ) === "\r\n" ) { + $result = substr( $result, 0, -2 ); + } elseif ( substr( $result, -1 ) === "\n" ) { + $result = substr( $result, 0, -1 ); } else { - $bytesWritten = fwrite( $f, $buf, $len ); + $this->_handle_error( $sock, 'line ending missing in response from $1' ); + return false; } - return $bytesWritten; + return $result; } /** * Flush the read buffer of a stream + * @param $f Resource */ function _flush_read_buffer( $f ) { if ( !is_resource( $f ) ) { @@ -1108,12 +1179,8 @@ class MWMemcached { // }}} } -// vim: sts=3 sw=3 et // }}} class MemCachedClientforWiki extends MWMemcached { - function _debugprint( $text ) { - wfDebug( "memcached: $text" ); - } } |