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Diffstat (limited to 'includes/memcached-client.php')
| -rw-r--r-- | includes/memcached-client.php | 1060 |
1 files changed, 1060 insertions, 0 deletions
diff --git a/includes/memcached-client.php b/includes/memcached-client.php new file mode 100644 index 00000000..697509e8 --- /dev/null +++ b/includes/memcached-client.php @@ -0,0 +1,1060 @@ +<?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. | +// +---------------------------------------------------------------------------+ +// +// $TCAnet$ +// + +/** + * This is the PHP client for memcached - a distributed memory cache daemon. + * More information is available at http://www.danga.com/memcached/ + * + * Usage example: + * + * require_once 'memcached.php'; + * + * $mc = new memcached(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, + * 'persistant' => true)); + * + * $mc->add('key', array('some', 'array')); + * $mc->replace('key', 'some random string'); + * $val = $mc->get('key'); + * + * @author Ryan T. Dean <rtdean@cytherianage.net> + * @package memcached-client + * @version 0.1.2 + */ + +// {{{ requirements +// }}} + +// {{{ constants +// {{{ flags + +/** + * Flag: indicates data is serialized + */ +define("MEMCACHE_SERIALIZED", 1<<0); + +/** + * Flag: indicates data is compressed + */ +define("MEMCACHE_COMPRESSED", 1<<1); + +// }}} + +/** + * Minimum savings to store data compressed + */ +define("COMPRESSION_SAVINGS", 0.20); + +// }}} + +// {{{ class memcached +/** + * memcached client class implemented using (p)fsockopen() + * + * @author Ryan T. Dean <rtdean@cytherianage.net> + * @package memcached-client + */ +class memcached +{ + // {{{ properties + // {{{ public + + /** + * Command statistics + * + * @var array + * @access public + */ + var $stats; + + // }}} + // {{{ private + + /** + * Cached Sockets that are connected + * + * @var array + * @access private + */ + var $_cache_sock; + + /** + * Current debug status; 0 - none to 9 - profiling + * + * @var boolean + * @access private + */ + var $_debug; + + /** + * Dead hosts, assoc array, 'host'=>'unixtime when ok to check again' + * + * @var array + * @access private + */ + var $_host_dead; + + /** + * Is compression available? + * + * @var boolean + * @access private + */ + var $_have_zlib; + + /** + * Do we want to use compression? + * + * @var boolean + * @access private + */ + var $_compress_enable; + + /** + * At how many bytes should we compress? + * + * @var interger + * @access private + */ + var $_compress_threshold; + + /** + * Are we using persistant links? + * + * @var boolean + * @access private + */ + var $_persistant; + + /** + * If only using one server; contains ip:port to connect to + * + * @var string + * @access private + */ + var $_single_sock; + + /** + * Array containing ip:port or array(ip:port, weight) + * + * @var array + * @access private + */ + var $_servers; + + /** + * Our bit buckets + * + * @var array + * @access private + */ + var $_buckets; + + /** + * Total # of bit buckets we have + * + * @var interger + * @access private + */ + var $_bucketcount; + + /** + * # of total servers we have + * + * @var interger + * @access private + */ + var $_active; + + /** + * Stream timeout in seconds. Applies for example to fread() + * + * @var integer + * @access private + */ + var $_timeout_seconds; + + /** + * Stream timeout in microseconds + * + * @var integer + * @access private + */ + var $_timeout_microseconds; + + // }}} + // }}} + // {{{ methods + // {{{ public functions + // {{{ memcached() + + /** + * Memcache initializer + * + * @param array $args Associative array of settings + * + * @return mixed + * @access public + */ + function memcached ($args) + { + $this->set_servers(@$args['servers']); + $this->_debug = @$args['debug']; + $this->stats = array(); + $this->_compress_threshold = @$args['compress_threshold']; + $this->_persistant = array_key_exists('persistant', $args) ? (@$args['persistant']) : false; + $this->_compress_enable = true; + $this->_have_zlib = function_exists("gzcompress"); + + $this->_cache_sock = array(); + $this->_host_dead = array(); + + $this->_timeout_seconds = 1; + $this->_timeout_microseconds = 0; + } + + // }}} + // {{{ 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 interger $exp (optional) Time to expire data at + * + * @return boolean + * @access public + */ + function add ($key, $val, $exp = 0) + { + return $this->_set('add', $key, $val, $exp); + } + + // }}} + // {{{ decr() + + /** + * Decriment a value stored on the memcache server + * + * @param string $key Key to decriment + * @param interger $amt (optional) Amount to decriment + * + * @return mixed FALSE on failure, value on success + * @access public + */ + function decr ($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 interger $time (optional) How long to wait before deleting + * + * @return boolean TRUE on success, FALSE on failure + * @access public + */ + function delete ($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] : $key; + + @$this->stats['delete']++; + $cmd = "delete $key $time\r\n"; + if(!$this->_safe_fwrite($sock, $cmd, strlen($cmd))) + { + $this->_dead_sock($sock); + return false; + } + $res = trim(fgets($sock)); + + if ($this->_debug) + $this->_debugprint(sprintf("MemCache: delete %s (%s)\n", $key, $res)); + + if ($res == "DELETED") + return true; + return false; + } + + // }}} + // {{{ disconnect_all() + + /** + * Disconnects all connected sockets + * + * @access public + */ + function disconnect_all () + { + foreach ($this->_cache_sock as $sock) + fclose($sock); + + $this->_cache_sock = array(); + } + + // }}} + // {{{ enable_compress() + + /** + * Enable / Disable compression + * + * @param boolean $enable TRUE to enable, FALSE to disable + * + * @access public + */ + function enable_compress ($enable) + { + $this->_compress_enable = $enable; + } + + // }}} + // {{{ forget_dead_hosts() + + /** + * Forget about all of the dead hosts + * + * @access public + */ + function forget_dead_hosts () + { + $this->_host_dead = array(); + } + + // }}} + // {{{ get() + + /** + * Retrieves the value associated with the key from the memcache server + * + * @param string $key Key to retrieve + * + * @return mixed + * @access public + */ + function get ($key) + { + $fname = 'memcached::get'; + wfProfileIn( $fname ); + + if (!$this->_active) { + wfProfileOut( $fname ); + return false; + } + + $sock = $this->get_sock($key); + + if (!is_resource($sock)) { + wfProfileOut( $fname ); + return false; + } + + @$this->stats['get']++; + + $cmd = "get $key\r\n"; + if (!$this->_safe_fwrite($sock, $cmd, strlen($cmd))) + { + $this->_dead_sock($sock); + wfProfileOut( $fname ); + return false; + } + + $val = array(); + $this->_load_items($sock, $val); + + if ($this->_debug) + foreach ($val as $k => $v) + $this->_debugprint(@sprintf("MemCache: sock %s got %s => %s\r\n", serialize($sock), $k, $v)); + + wfProfileOut( $fname ); + return @$val[$key]; + } + + // }}} + // {{{ get_multi() + + /** + * Get multiple keys from the server(s) + * + * @param array $keys Keys to retrieve + * + * @return array + * @access public + */ + function get_multi ($keys) + { + if (!$this->_active) + return false; + + $this->stats['get_multi']++; + + foreach ($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])) + { + $sock_keys[$sock] = array(); + $socks[] = $sock; + } + $sock_keys[$sock][] = $key; + } + + // Send out the requests + foreach ($socks as $sock) + { + $cmd = "get"; + foreach ($sock_keys[$sock] as $key) + { + $cmd .= " ". $key; + } + $cmd .= "\r\n"; + + if ($this->_safe_fwrite($sock, $cmd, strlen($cmd))) + { + $gather[] = $sock; + } else + { + $this->_dead_sock($sock); + } + } + + // Parse responses + $val = array(); + foreach ($gather as $sock) + { + $this->_load_items($sock, $val); + } + + if ($this->_debug) + foreach ($val as $k => $v) + $this->_debugprint(sprintf("MemCache: got %s => %s\r\n", $k, $v)); + + return $val; + } + + // }}} + // {{{ incr() + + /** + * Increments $key (optionally) by $amt + * + * @param string $key Key to increment + * @param interger $amt (optional) amount to increment + * + * @return interger New key value? + * @access public + */ + function incr ($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 interger $exp (optional) Experiation time + * + * @return boolean + * @access public + */ + function replace ($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) + * + * 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 resource $sock Socket to send command on + * @param string $cmd Command to run + * + * @return array Output array + * @access public + */ + function run_command ($sock, $cmd) + { + if (!is_resource($sock)) + return array(); + + if (!$this->_safe_fwrite($sock, $cmd, strlen($cmd))) + return array(); + + while (true) + { + $res = fgets($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 interger $exp (optional) Experiation time + * + * @return boolean TRUE on success + * @access public + */ + function set ($key, $value, $exp=0) + { + return $this->_set('set', $key, $value, $exp); + } + + // }}} + // {{{ set_compress_threshold() + + /** + * Sets the compression threshold + * + * @param interger $thresh Threshold to compress if larger than + * + * @access public + */ + function set_compress_threshold ($thresh) + { + $this->_compress_threshold = $thresh; + } + + // }}} + // {{{ set_debug() + + /** + * Sets the debug flag + * + * @param boolean $dbg TRUE for debugging, FALSE otherwise + * + * @access public + * + * @see memcahced::memcached + */ + function set_debug ($dbg) + { + $this->_debug = $dbg; + } + + // }}} + // {{{ set_servers() + + /** + * Sets the server list to distribute key gets and puts between + * + * @param array $list Array of servers to connect to + * + * @access public + * + * @see memcached::memcached() + */ + function set_servers ($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 integer $seconds Number of seconds + * @param integer $microseconds Number of microseconds + * + * @access public + */ + function set_timeout ($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 interger $sock Socket to connect + * @param string $host Host:IP to connect to + * @param float $timeout (optional) Timeout value, defaults to 0.25s + * + * @return boolean + * @access private + */ + function _connect_sock (&$sock, $host, $timeout = 0.25) + { + list ($ip, $port) = explode(":", $host); + if ($this->_persistant == 1) + { + $sock = @pfsockopen($ip, $port, $errno, $errstr, $timeout); + } else + { + $sock = @fsockopen($ip, $port, $errno, $errstr, $timeout); + } + + if (!$sock) { + if ($this->_debug) + $this->_debugprint( "Error connecting to $host: $errstr\n" ); + return false; + } + + // Initialise timeout + stream_set_timeout($sock, $this->_timeout_seconds, $this->_timeout_microseconds); + + 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, $this->_cache_sock); + @list ($ip, $port) = explode(":", $host); + $this->_host_dead[$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 $key Key to retrieve value for; + * + * @return mixed resource on success, false on failure + * @access private + */ + function get_sock ($key) + { + if (!$this->_active) + return false; + + if ($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 ($this->_buckets === null) + { + foreach ($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)) { + $this->_flush_read_buffer($sock); + return $sock; + } + $hv += $this->_hashfunc($tries . $realkey); + } + + return false; + } + + // }}} + // {{{ _hashfunc() + + /** + * Creates a hash interger based on the $key + * + * @param string $key Key to hash + * + * @return interger Hash value + * @access private + */ + function _hashfunc ($key) + { + # Hash function must on [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 $key Key to perform it on + * @param interger $amt Amount to adjust + * + * @return interger 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] : $key; + @$this->stats[$cmd]++; + if (!$this->_safe_fwrite($sock, "$cmd $key $amt\r\n")) + return $this->_dead_sock($sock); + + stream_set_timeout($sock, 1, 0); + $line = fgets($sock); + 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 $ret Returned values + * + * @access private + */ + function _load_items ($sock, &$ret) + { + while (1) + { + $decl = fgets($sock); + if ($decl == "END\r\n") + { + return true; + } elseif (preg_match('/^VALUE (\S+) (\d+) (\d+)\r\n$/', $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 -= $n; + @$ret[$rkey] .= $data; + } + + if ($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); + return false; + } + + if ($this->_have_zlib && $flags & MEMCACHE_COMPRESSED) + $ret[$rkey] = gzuncompress($ret[$rkey]); + + $ret[$rkey] = rtrim($ret[$rkey]); + + if ($flags & MEMCACHE_SERIALIZED) + $ret[$rkey] = unserialize($ret[$rkey]); + + } else + { + $this->_debugprint("Error parsing memcached response\n"); + return 0; + } + } + } + + // }}} + // {{{ _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 interger $exp When it should expire + * + * @return boolean + * @access private + */ + function _set ($cmd, $key, $val, $exp) + { + if (!$this->_active) + return false; + + $sock = $this->get_sock($key); + if (!is_resource($sock)) + return false; + + @$this->stats[$cmd]++; + + $flags = 0; + + if (!is_scalar($val)) + { + $val = serialize($val); + $flags |= MEMCACHE_SERIALIZED; + if ($this->_debug) + $this->_debugprint(sprintf("client: serializing data as it is not scalar\n")); + } + + $len = strlen($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 < $len*(1 - COMPRESSION_SAVINGS)) + { + if ($this->_debug) + $this->_debugprint(sprintf("client: compressing data; was %d bytes is now %d bytes\n", $len, $c_len)); + $val = $c_val; + $len = $c_len; + $flags |= MEMCACHE_COMPRESSED; + } + } + if (!$this->_safe_fwrite($sock, "$cmd $key $flags $exp $len\r\n$val\r\n")) + return $this->_dead_sock($sock); + + $line = trim(fgets($sock)); + + if ($this->_debug) + { + if ($flags & MEMCACHE_COMPRESSED) + $val = 'compressed data'; + $this->_debugprint(sprintf("MemCache: %s %s => %s (%s)\n", $cmd, $key, $val, $line)); + } + if ($line == "STORED") + return true; + return false; + } + + // }}} + // {{{ sock_to_host() + + /** + * Returns the socket for the host + * + * @param string $host Host:IP to get socket for + * + * @return mixed IO Stream or false + * @access private + */ + function sock_to_host ($host) + { + if (isset($this->_cache_sock[$host])) + return $this->_cache_sock[$host]; + + $now = time(); + list ($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 $this->_dead_sock($host); + + // Do not buffer writes + stream_set_write_buffer($sock, 0); + + $this->_cache_sock[$host] = $sock; + + return $this->_cache_sock[$host]; + } + + function _debugprint($str){ + print($str); + } + + /** + * Write to a stream, timing out after the correct amount of time + * + * @return bool false on failure, true on success + */ + /* + function _safe_fwrite($f, $buf, $len = false) { + stream_set_blocking($f, 0); + + if ($len === false) { + wfDebug("Writing " . strlen( $buf ) . " bytes\n"); + $bytesWritten = fwrite($f, $buf); + } else { + wfDebug("Writing $len bytes\n"); + $bytesWritten = fwrite($f, $buf, $len); + } + $n = stream_select($r=NULL, $w = array($f), $e = NULL, 10, 0); + # $this->_timeout_seconds, $this->_timeout_microseconds); + + wfDebug("stream_select returned $n\n"); + stream_set_blocking($f, 1); + return $n == 1; + return $bytesWritten; + }*/ + + /** + * Original behaviour + */ + function _safe_fwrite($f, $buf, $len = false) { + if ($len === false) { + $bytesWritten = fwrite($f, $buf); + } else { + $bytesWritten = fwrite($f, $buf, $len); + } + return $bytesWritten; + } + + /** + * Flush the read buffer of a stream + */ + function _flush_read_buffer($f) { + if (!is_resource($f)) { + return; + } + $n = stream_select($r=array($f), $w = NULL, $e = NULL, 0, 0); + while ($n == 1 && !feof($f)) { + fread($f, 1024); + $n = stream_select($r=array($f), $w = NULL, $e = NULL, 0, 0); + } + } + + // }}} + // }}} + // }}} +} + +// vim: sts=3 sw=3 et + +// }}} +?> |