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Diffstat (limited to 'www/wiki/includes/libs/objectcache/MemcachedClient.php')
| -rw-r--r-- | www/wiki/includes/libs/objectcache/MemcachedClient.php | 1314 |
1 files changed, 1314 insertions, 0 deletions
diff --git a/www/wiki/includes/libs/objectcache/MemcachedClient.php b/www/wiki/includes/libs/objectcache/MemcachedClient.php new file mode 100644 index 00000000..59131b97 --- /dev/null +++ b/www/wiki/includes/libs/objectcache/MemcachedClient.php @@ -0,0 +1,1314 @@ +<?php +// phpcs:ignoreFile -- It's an external lib and it isn't. Let's not bother. +/** + * Memcached client for PHP. + * + * +---------------------------------------------------------------------------+ + * | memcached client, PHP | + * +---------------------------------------------------------------------------+ + * | Copyright (c) 2003 Ryan T. Dean <rtdean@cytherianage.net> | + * | All rights reserved. | + * | | + * | Redistribution and use in source and binary forms, with or without | + * | modification, are permitted provided that the following conditions | + * | are met: | + * | | + * | 1. Redistributions of source code must retain the above copyright | + * | notice, this list of conditions and the following disclaimer. | + * | 2. Redistributions in binary form must reproduce the above copyright | + * | notice, this list of conditions and the following disclaimer in the | + * | documentation and/or other materials provided with the distribution. | + * | | + * | THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR | + * | IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES | + * | OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. | + * | IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, | + * | INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | + * | NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | + * | DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | + * | THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | + * | (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | + * | THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | + * +---------------------------------------------------------------------------+ + * | Author: Ryan T. Dean <rtdean@cytherianage.net> | + * | Heavily influenced by the Perl memcached client by Brad Fitzpatrick. | + * | Permission granted by Brad Fitzpatrick for relicense of ported Perl | + * | client logic under 2-clause BSD license. | + * +---------------------------------------------------------------------------+ + * + * @file + * $TCAnet$ + */ + +/** + * This is a PHP client for memcached - a distributed memory cache daemon. + * + * More information is available at http://www.danga.com/memcached/ + * + * Usage example: + * + * $mc = new MemcachedClient(array( + * 'servers' => array( + * '127.0.0.1:10000', + * array( '192.0.0.1:10010', 2 ), + * '127.0.0.1:10020' + * ), + * 'debug' => false, + * 'compress_threshold' => 10240, + * 'persistent' => true + * )); + * + * $mc->add( 'key', array( 'some', 'array' ) ); + * $mc->replace( 'key', 'some random string' ); + * $val = $mc->get( 'key' ); + * + * @author Ryan T. Dean <rtdean@cytherianage.net> + * @version 0.1.2 + */ + +use Psr\Log\LoggerInterface; +use Psr\Log\NullLogger; + +// {{{ class MemcachedClient +/** + * memcached client class implemented using (p)fsockopen() + * + * @author Ryan T. Dean <rtdean@cytherianage.net> + * @ingroup Cache + */ +class MemcachedClient { + // {{{ properties + // {{{ public + + // {{{ constants + // {{{ flags + + /** + * Flag: indicates data is serialized + */ + const SERIALIZED = 1; + + /** + * Flag: indicates data is compressed + */ + const COMPRESSED = 2; + + /** + * Flag: indicates data is an integer + */ + const INTVAL = 4; + + // }}} + + /** + * Minimum savings to store data compressed + */ + const COMPRESSION_SAVINGS = 0.20; + + // }}} + + /** + * Command statistics + * + * @var array + * @access public + */ + public $stats; + + // }}} + // {{{ private + + /** + * Cached Sockets that are connected + * + * @var array + * @access private + */ + public $_cache_sock; + + /** + * Current debug status; 0 - none to 9 - profiling + * + * @var bool + * @access private + */ + public $_debug; + + /** + * Dead hosts, assoc array, 'host'=>'unixtime when ok to check again' + * + * @var array + * @access private + */ + public $_host_dead; + + /** + * Is compression available? + * + * @var bool + * @access private + */ + public $_have_zlib; + + /** + * Do we want to use compression? + * + * @var bool + * @access private + */ + public $_compress_enable; + + /** + * At how many bytes should we compress? + * + * @var int + * @access private + */ + public $_compress_threshold; + + /** + * Are we using persistent links? + * + * @var bool + * @access private + */ + public $_persistent; + + /** + * If only using one server; contains ip:port to connect to + * + * @var string + * @access private + */ + public $_single_sock; + + /** + * Array containing ip:port or array(ip:port, weight) + * + * @var array + * @access private + */ + public $_servers; + + /** + * Our bit buckets + * + * @var array + * @access private + */ + public $_buckets; + + /** + * Total # of bit buckets we have + * + * @var int + * @access private + */ + public $_bucketcount; + + /** + * # of total servers we have + * + * @var int + * @access private + */ + public $_active; + + /** + * Stream timeout in seconds. Applies for example to fread() + * + * @var int + * @access private + */ + public $_timeout_seconds; + + /** + * Stream timeout in microseconds + * + * @var int + * @access private + */ + public $_timeout_microseconds; + + /** + * Connect timeout in seconds + */ + public $_connect_timeout; + + /** + * Number of connection attempts for each server + */ + public $_connect_attempts; + + /** + * @var LoggerInterface + */ + private $_logger; + + // }}} + // }}} + // {{{ methods + // {{{ public functions + // {{{ memcached() + + /** + * Memcache initializer + * + * @param array $args Associative array of settings + * + * @return mixed + */ + public function __construct( $args ) { + $this->set_servers( isset( $args['servers'] ) ? $args['servers'] : array() ); + $this->_debug = isset( $args['debug'] ) ? $args['debug'] : false; + $this->stats = array(); + $this->_compress_threshold = isset( $args['compress_threshold'] ) ? $args['compress_threshold'] : 0; + $this->_persistent = isset( $args['persistent'] ) ? $args['persistent'] : false; + $this->_compress_enable = true; + $this->_have_zlib = function_exists( 'gzcompress' ); + + $this->_cache_sock = array(); + $this->_host_dead = array(); + + $this->_timeout_seconds = 0; + $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; + + $this->_logger = isset( $args['logger'] ) ? $args['logger'] : new NullLogger(); + } + + // }}} + // {{{ add() + + /** + * Adds a key/value to the memcache server if one isn't already set with + * that key + * + * @param string $key Key to set with data + * @param mixed $val Value to store + * @param int $exp (optional) Expiration time. This can be a number of seconds + * to cache for (up to 30 days inclusive). Any timespans of 30 days + 1 second or + * longer must be the timestamp of the time at which the mapping should expire. It + * is safe to use timestamps in all cases, regardless of expiration + * eg: strtotime("+3 hour") + * + * @return bool + */ + public function add( $key, $val, $exp = 0 ) { + return $this->_set( 'add', $key, $val, $exp ); + } + + // }}} + // {{{ decr() + + /** + * Decrease a value stored on the memcache server + * + * @param string $key Key to decrease + * @param int $amt (optional) amount to decrease + * + * @return mixed False on failure, value on success + */ + public function decr( $key, $amt = 1 ) { + return $this->_incrdecr( 'decr', $key, $amt ); + } + + // }}} + // {{{ delete() + + /** + * Deletes a key from the server, optionally after $time + * + * @param string $key Key to delete + * @param int $time (optional) how long to wait before deleting + * + * @return bool True on success, false on failure + */ + public function delete( $key, $time = 0 ) { + if ( !$this->_active ) { + return false; + } + + $sock = $this->get_sock( $key ); + if ( !is_resource( $sock ) ) { + return false; + } + + $key = is_array( $key ) ? $key[1] : $key; + + if ( isset( $this->stats['delete'] ) ) { + $this->stats['delete']++; + } else { + $this->stats['delete'] = 1; + } + $cmd = "delete $key $time\r\n"; + if ( !$this->_fwrite( $sock, $cmd ) ) { + return false; + } + $res = $this->_fgets( $sock ); + + if ( $this->_debug ) { + $this->_debugprint( sprintf( "MemCache: delete %s (%s)", $key, $res ) ); + } + + if ( $res == "DELETED" || $res == "NOT_FOUND" ) { + return true; + } + + return false; + } + + /** + * Changes the TTL on a key from the server to $time + * + * @param string $key + * @param int $time TTL in seconds + * + * @return bool True on success, false on failure + */ + public function touch( $key, $time = 0 ) { + if ( !$this->_active ) { + return false; + } + + $sock = $this->get_sock( $key ); + if ( !is_resource( $sock ) ) { + return false; + } + + $key = is_array( $key ) ? $key[1] : $key; + + if ( isset( $this->stats['touch'] ) ) { + $this->stats['touch']++; + } else { + $this->stats['touch'] = 1; + } + $cmd = "touch $key $time\r\n"; + if ( !$this->_fwrite( $sock, $cmd ) ) { + return false; + } + $res = $this->_fgets( $sock ); + + if ( $this->_debug ) { + $this->_debugprint( sprintf( "MemCache: touch %s (%s)", $key, $res ) ); + } + + if ( $res == "TOUCHED" ) { + return true; + } + + return false; + } + + /** + * @param string $key + * @param int $timeout + * @return bool + */ + public function lock( $key, $timeout = 0 ) { + /* stub */ + return true; + } + + /** + * @param string $key + * @return bool + */ + public function unlock( $key ) { + /* stub */ + return true; + } + + // }}} + // {{{ disconnect_all() + + /** + * Disconnects all connected sockets + */ + public function disconnect_all() { + foreach ( $this->_cache_sock as $sock ) { + fclose( $sock ); + } + + $this->_cache_sock = array(); + } + + // }}} + // {{{ enable_compress() + + /** + * Enable / Disable compression + * + * @param bool $enable True to enable, false to disable + */ + public function enable_compress( $enable ) { + $this->_compress_enable = $enable; + } + + // }}} + // {{{ forget_dead_hosts() + + /** + * Forget about all of the dead hosts + */ + public function forget_dead_hosts() { + $this->_host_dead = array(); + } + + // }}} + // {{{ get() + + /** + * Retrieves the value associated with the key from the memcache server + * + * @param array|string $key key to retrieve + * @param float $casToken [optional] + * + * @return mixed + */ + public function get( $key, &$casToken = null ) { + if ( $this->_debug ) { + $this->_debugprint( "get($key)" ); + } + + if ( !is_array( $key ) && strval( $key ) === '' ) { + $this->_debugprint( "Skipping key which equals to an empty string" ); + return false; + } + + if ( !$this->_active ) { + return false; + } + + $sock = $this->get_sock( $key ); + + if ( !is_resource( $sock ) ) { + return false; + } + + $key = is_array( $key ) ? $key[1] : $key; + if ( isset( $this->stats['get'] ) ) { + $this->stats['get']++; + } else { + $this->stats['get'] = 1; + } + + $cmd = "gets $key\r\n"; + if ( !$this->_fwrite( $sock, $cmd ) ) { + return false; + } + + $val = array(); + $this->_load_items( $sock, $val, $casToken ); + + if ( $this->_debug ) { + foreach ( $val as $k => $v ) { + $this->_debugprint( sprintf( "MemCache: sock %s got %s", serialize( $sock ), $k ) ); + } + } + + $value = false; + if ( isset( $val[$key] ) ) { + $value = $val[$key]; + } + return $value; + } + + // }}} + // {{{ get_multi() + + /** + * Get multiple keys from the server(s) + * + * @param array $keys Keys to retrieve + * + * @return array + */ + public function get_multi( $keys ) { + if ( !$this->_active ) { + return array(); + } + + if ( isset( $this->stats['get_multi'] ) ) { + $this->stats['get_multi']++; + } else { + $this->stats['get_multi'] = 1; + } + $sock_keys = array(); + $socks = array(); + foreach ( $keys as $key ) { + $sock = $this->get_sock( $key ); + if ( !is_resource( $sock ) ) { + continue; + } + $key = is_array( $key ) ? $key[1] : $key; + if ( !isset( $sock_keys[$sock] ) ) { + $sock_keys[intval( $sock )] = array(); + $socks[] = $sock; + } + $sock_keys[intval( $sock )][] = $key; + } + + $gather = array(); + // Send out the requests + foreach ( $socks as $sock ) { + $cmd = 'gets'; + foreach ( $sock_keys[intval( $sock )] as $key ) { + $cmd .= ' ' . $key; + } + $cmd .= "\r\n"; + + if ( $this->_fwrite( $sock, $cmd ) ) { + $gather[] = $sock; + } + } + + // Parse responses + $val = array(); + foreach ( $gather as $sock ) { + $this->_load_items( $sock, $val, $casToken ); + } + + if ( $this->_debug ) { + foreach ( $val as $k => $v ) { + $this->_debugprint( sprintf( "MemCache: got %s", $k ) ); + } + } + + return $val; + } + + // }}} + // {{{ incr() + + /** + * Increments $key (optionally) by $amt + * + * @param string $key Key to increment + * @param int $amt (optional) amount to increment + * + * @return int|null Null if the key does not exist yet (this does NOT + * create new mappings if the key does not exist). If the key does + * exist, this returns the new value for that key. + */ + public function incr( $key, $amt = 1 ) { + return $this->_incrdecr( 'incr', $key, $amt ); + } + + // }}} + // {{{ replace() + + /** + * Overwrites an existing value for key; only works if key is already set + * + * @param string $key Key to set value as + * @param mixed $value Value to store + * @param int $exp (optional) Expiration time. This can be a number of seconds + * to cache for (up to 30 days inclusive). Any timespans of 30 days + 1 second or + * longer must be the timestamp of the time at which the mapping should expire. It + * is safe to use timestamps in all cases, regardless of exipration + * eg: strtotime("+3 hour") + * + * @return bool + */ + public function replace( $key, $value, $exp = 0 ) { + return $this->_set( 'replace', $key, $value, $exp ); + } + + // }}} + // {{{ run_command() + + /** + * Passes through $cmd to the memcache server connected by $sock; returns + * output as an array (null array if no output) + * + * @param Resource $sock Socket to send command on + * @param string $cmd Command to run + * + * @return array Output array + */ + public function run_command( $sock, $cmd ) { + if ( !is_resource( $sock ) ) { + return array(); + } + + if ( !$this->_fwrite( $sock, $cmd ) ) { + return array(); + } + + $ret = array(); + while ( true ) { + $res = $this->_fgets( $sock ); + $ret[] = $res; + if ( preg_match( '/^END/', $res ) ) { + break; + } + if ( strlen( $res ) == 0 ) { + break; + } + } + return $ret; + } + + // }}} + // {{{ set() + + /** + * Unconditionally sets a key to a given value in the memcache. Returns true + * if set successfully. + * + * @param string $key Key to set value as + * @param mixed $value Value to set + * @param int $exp (optional) Expiration time. This can be a number of seconds + * to cache for (up to 30 days inclusive). Any timespans of 30 days + 1 second or + * longer must be the timestamp of the time at which the mapping should expire. It + * is safe to use timestamps in all cases, regardless of exipration + * eg: strtotime("+3 hour") + * + * @return bool True on success + */ + public function set( $key, $value, $exp = 0 ) { + return $this->_set( 'set', $key, $value, $exp ); + } + + // }}} + // {{{ cas() + + /** + * Sets a key to a given value in the memcache if the current value still corresponds + * to a known, given value. Returns true if set successfully. + * + * @param float $casToken Current known value + * @param string $key Key to set value as + * @param mixed $value Value to set + * @param int $exp (optional) Expiration time. This can be a number of seconds + * to cache for (up to 30 days inclusive). Any timespans of 30 days + 1 second or + * longer must be the timestamp of the time at which the mapping should expire. It + * is safe to use timestamps in all cases, regardless of exipration + * eg: strtotime("+3 hour") + * + * @return bool True on success + */ + public function cas( $casToken, $key, $value, $exp = 0 ) { + return $this->_set( 'cas', $key, $value, $exp, $casToken ); + } + + // }}} + // {{{ set_compress_threshold() + + /** + * Set the compression threshold + * + * @param int $thresh Threshold to compress if larger than + */ + public function set_compress_threshold( $thresh ) { + $this->_compress_threshold = $thresh; + } + + // }}} + // {{{ set_debug() + + /** + * Set the debug flag + * + * @see __construct() + * @param bool $dbg True for debugging, false otherwise + */ + public function set_debug( $dbg ) { + $this->_debug = $dbg; + } + + // }}} + // {{{ set_servers() + + /** + * Set the server list to distribute key gets and puts between + * + * @see __construct() + * @param array $list Array of servers to connect to + */ + public function set_servers( $list ) { + $this->_servers = $list; + $this->_active = count( $list ); + $this->_buckets = null; + $this->_bucketcount = 0; + + $this->_single_sock = null; + if ( $this->_active == 1 ) { + $this->_single_sock = $this->_servers[0]; + } + } + + /** + * Sets the timeout for new connections + * + * @param int $seconds Number of seconds + * @param int $microseconds Number of microseconds + */ + public function set_timeout( $seconds, $microseconds ) { + $this->_timeout_seconds = $seconds; + $this->_timeout_microseconds = $microseconds; + } + + // }}} + // }}} + // {{{ private methods + // {{{ _close_sock() + + /** + * Close the specified socket + * + * @param string $sock Socket to close + * + * @access private + */ + function _close_sock( $sock ) { + $host = array_search( $sock, $this->_cache_sock ); + fclose( $this->_cache_sock[$host] ); + unset( $this->_cache_sock[$host] ); + } + + // }}} + // {{{ _connect_sock() + + /** + * Connects $sock to $host, timing out after $timeout + * + * @param int $sock Socket to connect + * @param string $host Host:IP to connect to + * + * @return bool + * @access private + */ + function _connect_sock( &$sock, $host ) { + list( $ip, $port ) = preg_split( '/:(?=\d)/', $host ); + $sock = false; + $timeout = $this->_connect_timeout; + $errno = $errstr = null; + for ( $i = 0; !$sock && $i < $this->_connect_attempts; $i++ ) { + Wikimedia\suppressWarnings(); + if ( $this->_persistent == 1 ) { + $sock = pfsockopen( $ip, $port, $errno, $errstr, $timeout ); + } else { + $sock = fsockopen( $ip, $port, $errno, $errstr, $timeout ); + } + Wikimedia\restoreWarnings(); + } + if ( !$sock ) { + $this->_error_log( "Error connecting to $host: $errstr" ); + $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; + } + + // }}} + // {{{ _dead_sock() + + /** + * Marks a host as dead until 30-40 seconds in the future + * + * @param string $sock Socket to mark as dead + * + * @access private + */ + function _dead_sock( $sock ) { + $host = array_search( $sock, $this->_cache_sock ); + $this->_dead_host( $host ); + } + + /** + * @param string $host + */ + function _dead_host( $host ) { + $ip = explode( ':', $host )[0]; + $this->_host_dead[$ip] = time() + 30 + intval( rand( 0, 10 ) ); + $this->_host_dead[$host] = $this->_host_dead[$ip]; + unset( $this->_cache_sock[$host] ); + } + + // }}} + // {{{ get_sock() + + /** + * get_sock + * + * @param string $key Key to retrieve value for; + * + * @return Resource|bool Resource on success, false on failure + * @access private + */ + function get_sock( $key ) { + if ( !$this->_active ) { + return false; + } + + if ( $this->_single_sock !== null ) { + 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++ ) { + $bu[] = $v[0]; + } + } else { + $bu[] = $v; + } + } + $this->_buckets = $bu; + $this->_bucketcount = count( $bu ); + } + + $realkey = is_array( $key ) ? $key[1] : $key; + for ( $tries = 0; $tries < 20; $tries++ ) { + $host = $this->_buckets[$hv % $this->_bucketcount]; + $sock = $this->sock_to_host( $host ); + if ( is_resource( $sock ) ) { + return $sock; + } + $hv = $this->_hashfunc( $hv . $realkey ); + } + + return false; + } + + // }}} + // {{{ _hashfunc() + + /** + * Creates a hash integer based on the $key + * + * @param string $key Key to hash + * + * @return int Hash value + * @access private + */ + function _hashfunc( $key ) { + # 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; + } + + // }}} + // {{{ _incrdecr() + + /** + * Perform increment/decriment on $key + * + * @param string $cmd Command to perform + * @param string|array $key Key to perform it on + * @param int $amt Amount to adjust + * + * @return int New value of $key + * @access private + */ + function _incrdecr( $cmd, $key, $amt = 1 ) { + if ( !$this->_active ) { + return null; + } + + $sock = $this->get_sock( $key ); + if ( !is_resource( $sock ) ) { + return null; + } + + $key = is_array( $key ) ? $key[1] : $key; + if ( isset( $this->stats[$cmd] ) ) { + $this->stats[$cmd]++; + } else { + $this->stats[$cmd] = 1; + } + if ( !$this->_fwrite( $sock, "$cmd $key $amt\r\n" ) ) { + return null; + } + + $line = $this->_fgets( $sock ); + $match = array(); + if ( !preg_match( '/^(\d+)/', $line, $match ) ) { + return null; + } + return $match[1]; + } + + // }}} + // {{{ _load_items() + + /** + * Load items into $ret from $sock + * + * @param Resource $sock Socket to read from + * @param array $ret returned values + * @param float $casToken [optional] + * @return bool True for success, false for failure + * + * @access private + */ + function _load_items( $sock, &$ret, &$casToken = null ) { + $results = array(); + + while ( 1 ) { + $decl = $this->_fgets( $sock ); + + if ( $decl === false ) { + /* + * If nothing can be read, something is wrong because we know exactly when + * to stop reading (right after "END") and we return right after that. + */ + return false; + } elseif ( preg_match( '/^VALUE (\S+) (\d+) (\d+) (\d+)$/', $decl, $match ) ) { + /* + * Read all data returned. This can be either one or multiple values. + * Save all that data (in an array) to be processed later: we'll first + * want to continue reading until "END" before doing anything else, + * to make sure that we don't leave our client in a state where it's + * output is not yet fully read. + */ + $results[] = array( + $match[1], // rkey + $match[2], // flags + $match[3], // len + $match[4], // casToken + $this->_fread( $sock, $match[3] + 2 ), // data + ); + } elseif ( $decl == "END" ) { + if ( count( $results ) == 0 ) { + return false; + } + + /** + * All data has been read, time to process the data and build + * meaningful return values. + */ + foreach ( $results as $vars ) { + list( $rkey, $flags, $len, $casToken, $data ) = $vars; + + if ( $data === false || 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] ); + } + + /* + * This unserialize is the exact reason that we only want to + * process data after having read until "END" (instead of doing + * this right away): "unserialize" can trigger outside code: + * in the event that $ret[$rkey] is a serialized object, + * unserializing it will trigger __wakeup() if present. If that + * function attempted to read from memcached (while we did not + * yet read "END"), these 2 calls would collide. + */ + if ( $flags & self::SERIALIZED ) { + $ret[$rkey] = unserialize( $ret[$rkey] ); + } elseif ( $flags & self::INTVAL ) { + $ret[$rkey] = intval( $ret[$rkey] ); + } + } + + return true; + } else { + $this->_handle_error( $sock, 'Error parsing response from $1' ); + return false; + } + } + } + + // }}} + // {{{ _set() + + /** + * Performs the requested storage operation to the memcache server + * + * @param string $cmd Command to perform + * @param string $key Key to act on + * @param mixed $val What we need to store + * @param int $exp (optional) Expiration time. This can be a number of seconds + * to cache for (up to 30 days inclusive). Any timespans of 30 days + 1 second or + * longer must be the timestamp of the time at which the mapping should expire. It + * is safe to use timestamps in all cases, regardless of exipration + * eg: strtotime("+3 hour") + * @param float $casToken [optional] + * + * @return bool + * @access private + */ + function _set( $cmd, $key, $val, $exp, $casToken = null ) { + if ( !$this->_active ) { + return false; + } + + $sock = $this->get_sock( $key ); + if ( !is_resource( $sock ) ) { + return false; + } + + if ( isset( $this->stats[$cmd] ) ) { + $this->stats[$cmd]++; + } else { + $this->stats[$cmd] = 1; + } + + $flags = 0; + + if ( is_int( $val ) ) { + $flags |= self::INTVAL; + } elseif ( !is_scalar( $val ) ) { + $val = serialize( $val ); + $flags |= self::SERIALIZED; + if ( $this->_debug ) { + $this->_debugprint( sprintf( "client: serializing data as it is not scalar" ) ); + } + } + + $len = strlen( $val ); + + if ( $this->_have_zlib && $this->_compress_enable + && $this->_compress_threshold && $len >= $this->_compress_threshold + ) { + $c_val = gzcompress( $val, 9 ); + $c_len = strlen( $c_val ); + + if ( $c_len < $len * ( 1 - self::COMPRESSION_SAVINGS ) ) { + if ( $this->_debug ) { + $this->_debugprint( sprintf( "client: compressing data; was %d bytes is now %d bytes", $len, $c_len ) ); + } + $val = $c_val; + $len = $c_len; + $flags |= self::COMPRESSED; + } + } + + $command = "$cmd $key $flags $exp $len"; + if ( $casToken ) { + $command .= " $casToken"; + } + + if ( !$this->_fwrite( $sock, "$command\r\n$val\r\n" ) ) { + return false; + } + + $line = $this->_fgets( $sock ); + + if ( $this->_debug ) { + $this->_debugprint( sprintf( "%s %s (%s)", $cmd, $key, $line ) ); + } + if ( $line === "STORED" ) { + return true; + } elseif ( $line === "NOT_STORED" && $cmd === "set" ) { + // "Not stored" is always used as the mcrouter response with AllAsyncRoute + return true; + } + + return false; + } + + // }}} + // {{{ sock_to_host() + + /** + * Returns the socket for the host + * + * @param string $host Host:IP to get socket for + * + * @return Resource|bool IO Stream or false + * @access private + */ + function sock_to_host( $host ) { + if ( isset( $this->_cache_sock[$host] ) ) { + return $this->_cache_sock[$host]; + } + + $sock = null; + $now = time(); + list( $ip, /* $port */) = explode( ':', $host ); + if ( isset( $this->_host_dead[$host] ) && $this->_host_dead[$host] > $now || + isset( $this->_host_dead[$ip] ) && $this->_host_dead[$ip] > $now + ) { + return null; + } + + if ( !$this->_connect_sock( $sock, $host ) ) { + return null; + } + + // Do not buffer writes + stream_set_write_buffer( $sock, 0 ); + + $this->_cache_sock[$host] = $sock; + + return $this->_cache_sock[$host]; + } + + /** + * @param string $text + */ + function _debugprint( $text ) { + $this->_logger->debug( $text ); + } + + /** + * @param string $text + */ + function _error_log( $text ) { + $this->_logger->error( "Memcached error: $text" ); + } + + /** + * Write to a stream. If there is an error, mark the socket dead. + * + * @param Resource $sock The socket + * @param string $buf The string to write + * @return bool True on success, false on failure + */ + 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; + } + + return true; + } + + /** + * Handle an I/O error. Mark the socket dead and log an error. + * + * @param Resource $sock + * @param string $msg + */ + 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]'; + } + } + $msg = str_replace( '$1', $peer, $msg ); + $this->_error_log( "$msg" ); + $this->_dead_sock( $sock ); + } + + /** + * Read the specified number of bytes from a stream. If there is an error, + * mark the socket dead. + * + * @param Resource $sock The socket + * @param int $len The number of bytes to read + * @return string|bool 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; + } + + /** + * 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 Resource $sock The socket + * @return string|bool The string on success, false on failure + */ + 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 { + $this->_handle_error( $sock, 'line ending missing in response from $1' ); + return false; + } + return $result; + } + + /** + * Flush the read buffer of a stream + * @param Resource $f + */ + function _flush_read_buffer( $f ) { + if ( !is_resource( $f ) ) { + return; + } + $r = array( $f ); + $w = null; + $e = null; + $n = stream_select( $r, $w, $e, 0, 0 ); + while ( $n == 1 && !feof( $f ) ) { + fread( $f, 1024 ); + $r = array( $f ); + $w = null; + $e = null; + $n = stream_select( $r, $w, $e, 0, 0 ); + } + } + + // }}} + // }}} + // }}} +} + +// }}} |