模拟PHP Memcache 类。
当服务器没有开启Memcache扩展的时候。可以采用本类
使用方法
class_exists('Memcache') or include './Memcache.class.php';
$mem = new Memcache;
$mem->add('key','value');
$mem->get('key')
目前已实现方法
Memcache::connect ( string $host [, int $port ] )
Memcache::get( string $key )
Memcache::add( string $key , mixed $var [, int $expire] )
Memcache::set( string $key , mixed $var [, int $expire] )
Memcache::replace( string $key , mixed $var [, int $expire] )
Memcache::getVersion( void )
Memcache::flush ( void )
Memcache::delete( string $key )
Memcache::close( void )
属性
Memcache::info 服务器相关信息 返回数组
注意 2014年3月28日
本类需要sockets支持
本类的 指定Memcache下标长度超出32字节。自动对key进行MD5
@Version Memcache.class.php 1.1 2014-3-29 04:10:18 $
bug 修复
1. 修复必须需要sockets扩展才能使用的缺陷
2. 代码优化
3. 添加手动关闭 连接方法
/**
* Created by Iyoule .
* 模拟PHP Memcache 类。
* 当服务器没有开启Memcache扩展的时候。可以采用本类
* 使用方法
* class_exists('Memcache') or include './Memcache.class.php';
* $mem = new Memcache;
* $mem->add('key','value');
* $mem->get('key')
* 目前已实现方法
* Memcache::connect ( string $host [, int $port ] )
* Memcache::get( string $key )
* Memcache::add( string $key , mixed $var [, int $expire] )
* Memcache::set( string $key , mixed $var [, int $expire] )
* Memcache::replace( string $key , mixed $var [, int $expire] )
* Memcache::getVersion( void )
* Memcache::flush ( void )
* Memcache::delete( string $key )
* Memcache::close( void ) 2014-3-29 02:13:19
*
* 属性
* Memcache::info 服务器相关信息 返回数组
*
* 注意
* 本类需要sockets支持
* 本类的 指定Memcache下标长度超出32字节。自动对key进行MD5
*
* @Version Memcache.class.php 1.1 2014-3-29 04:10:18 $
* bug 修复
* 1. 修复必须需要sockets扩展才能使用的缺陷
* 2. 代码优化
* 3. 添加手动关闭 连接方法
*
* Version: Memcache.class.php 1.1 $
* Time: 2014-3-28 上午12:04
*/
class Memcache
{
/**
* @var 服务器地址
*/
public $host; /**
* @var 服务器端口
*/
public $port; /**
* @var array memcache 服务信息
*/
private $info = array(); /**
* @var null socket资源
*/
private $socket = null; /**
* @var memcache 命令
*/
private $command; /**
* @var int 连接超时时间
*/
private $connect_timeout = 30;
private $errno;
private $errstr; /**
* @var mamcache保存数据时长
*/
private $expire; /**
* @var memcache 保存数据的key 长于32位置将被MD5
*/
private $key; /**
* @var memcache 保存的值
*/
private $var; /**
* @var bool 主机是否关闭连接
*/
private $is_close = false; /**
* @var string 连接函数
*/
private $connect_method; /**
* 构造方法 判断 根据系统自动判断连接类型
* 优先级
* 优先 -> 低
* stream_socket_client -> fsockopen -> pfsockopen -> socket_create
*/
public function __construct()
{
if (function_exists('stream_socket_client')) {
$this->connect_method = 'stream_socket_client';
} elseif (function_exists('fsockopen')) {
$this->connect_method = 'fsockopen';
} elseif (function_exists('pfsockopen')) {
$this->connect_method = 'pfsockopen';
} elseif (function_exists('socket_create')) {
$this->connect_method = 'socket_create';
}
} /**
* 从服务端检回一个元素
* 如果服务端之前有以key作为key存储的元素， Memcache::get()方法此时返回之前存储的值。
* 你可以给 Memcache::get()方法传递一个数组（多个key）来获取一个数组的元素值，返回的数组仅仅包含从 服务端查找到的key-value对。
* @param $key 要获取值的key或key数组。
* @return bool|string 返回key对应的存储元素的字符串值或者在失败或key未找到的时候返回FALSE。
* @lastTime 2014-3-28 02:44:00
*/
public function get($key)
{
$this->key = isset($key{32}) ? md5($key) : $key;
$command = "get $key\r\n";
$this->socket_write($command);
do {
$out = $this->socket_read(128);
} while (strlen($out) == 1);
$list = preg_split("/\s/", $out);
if ($list[0] == 'END') return false;
$string = array();
$runing = 0;
do {
$string[$runing] = $this->socket_read(128);
substr($string[$runing], 0, 3) == 'END' && strlen($string[$runing]) <= 5 ? $runing = false : $runing++;
} while ($runing !== false);
array_pop($string);
$string = join('', $string);
$indexOf = 0;
if ($this->connect_method == 'socket_create') {
$indexOf = 1;
}
$string = substr($string, $indexOf, -2);
return $string;
} /**
* 建立连接
* @param $host memcache 服务器地址
* @param int $post 端口
* @lastTime 2014-3-28 02:40:09
*/
public function connect($host, $post = 11211)
{
$this->host = $host;
$this->port = $post;
$this->create_socket();
$this->info();
} /**
* 魔法方法 构造 add set replace方法
* @param $method
* @param $args
* @return mixed
* @lastTime 2014-3-28 02:40:28
*/
public function __call($method, $args)
{
if (in_array($method, array('add', 'set', 'replace', 'delete'))) {
array_unshift($args, $method);
return call_user_func_array(array($this, 'set__'), $args);
}
} /**
* 魔法方法
* @param $name
* @return array
* @lastTime 2014-3-29 04:17:17
*/
public function __get($name)
{
if($name=='info')
return $this->info;
} /**
* 针对 魔法方法 add set replace方法进行的处理
* @param $func 方法名字
* @param $key memcache的key下标
* @param $var 设置的值
* @param int $expire memcache对数据的保存时间 默认24小时
* @return bool
* @lastTime 时间
*/
private function set__($func, $key, $var = null, $expire = 86400)
{
if ($this->is_close)
return false;
$this->command = trim($func);
$this->key = isset($key{32}) ? md5($key) : $key;
if ($func != 'delete') {
$this->var = trim($var);
$this->expire = trim($expire);
}
return $this->send_do();
} /**
* 清空memcache的值
* @return bool
* @lastTime 2014-3-28 02:43:23
*/
public function flush()
{
$command = "flush_all\r\n";
$this->socket_write($command);
if ($this->socket_read(3) == 'OK') {
return true;
}
return false;
} /**
* Memcache::getVersion — 返回服务器版本信息
* Memcache::getVersion()返回一个字符串表示的服务端版本号
* 同样你也可以使用 Memcache::info['version']。
* @return mixed
* @lastTime 2014-3-28 02:44:56
*/
public function getVersion()
{
return $this->info['version'];
} /**
* 对 add set replace delete 方法进行的处理
* @return bool
* @lastTime 2014-3-28 02:45:55
*/
private function send_do()
{
if ($this->command != 'delete') {
$command = sprintf("%s %s 0 %d %d\r\n", $this->command, $this->key, $this->expire, strlen($this->var));
$var = sprintf("%s\r\n", $this->var);
$this->socket_write($command);
$this->socket_write($var);
} else {
$command = sprintf("%s %s\r\n", $this->command, $this->key);
$this->socket_write($command);
}
do {
$result = $this->socket_read(64);
} while (strlen($result) == 1);
$result = str_replace(array("\r", "\n"), '', $result);
if (substr($result, 0, 5) == 'STORE' || substr($result, 0, 6) == 'DELETE') {
return true;
}
return false;
} /**
* 创建连接类型
* @return bool
* @lastTime 2014-3-29 04:06:15
*/
private function create_socket()
{
$method = $this->connect_method;
if ($method) {
switch ($method) {
case 'socket_create':
$this->socket = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
socket_connect($this->socket, $this->host, $this->port);
break;
case 'fsockopen':
case 'pfsockopen':
$this->socket = $method($this->host, $this->port, $this->errno, $this->errstr, $this->connect_timeout);
break;
case 'stream_socket_client':
$address = sprintf("tcp://%s:%d", $this->host, $this->port);
$this->socket = $method($address, $this->errno, $this->errstr, $this->connect_timeout);
break;
}
}
if (is_resource($this->socket))
return true;
} /**
* 写入套字节
* @param $string
* @return int
* @lastTime 2014-3-28 02:46:40
*/
private function socket_write($string)
{
$return = false;
if ($this->connect_method == 'socket_create')
$return = socket_write($this->socket, $string, strlen($string));
else if ($this->connect_method)
$return = fwrite($this->socket, $string);
return $return;
} /**
* 读取套字节
* @param $len 取出的长度
* @return string
* @lastTime 2014-3-28 02:47:08
*/
private function socket_read($len)
{
$return = null;
if ($this->connect_method == 'socket_create')
$return = socket_read($this->socket, $len, PHP_NORMAL_READ);
else if ($this->connect_method)
$return = fgets($this->socket, $len);
return $return;
} /**
* 服务器的信息处理
* @return array
* @lastTime 2014-3-28 02:47:46
*/
private function info()
{
if (!empty($this->info))
return $this->info;
$this->socket_write("stats\r\n");
$string = array();
if ($this->connect_method) {
$runing = 0;
do {
$string[$runing] = $this->socket_read(68);
substr($string[$runing], 0, 3) == 'END' ? $runing = false : $runing++;
} while ($runing !== false);
$string = join("\r\n", $string);
$string = explode("\r\n", $string);
$string = array_filter($string, function ($value) {
return isset($value{4});
});
$string = array_map(function ($value) {
return explode(" ", $value);
}, $string);
foreach ($string as $val) {
$this->info[$val[1]] = $val[2];
}
return $this->info;
}
} /**
* memcache 关闭连接
* @return bool
* @lastTime 2014-3-29 01:11:23
*/
public function close()
{
$this->is_close = true;
return !!$this->socket_write("quit\r\n");
} /**
* 析构函数 关闭套字节
*/
public function __destruct()
{
if (is_resource($this->socket) && $this->connect_method == 'socket_create')
socket_close($this->socket);
else if ($this->connect_method)
fclose($this->socket);
} }
类二:
memcached-client.php
<?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; // }}}
// }}}
// {{{ 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'];
$this->_persistant = isset($args['persistant']) ? $args['persistant'] : false;
$this->_compress_enable = true;
$this->_have_zlib = function_exists("gzcompress"); $this->_cache_sock = array();
$this->_host_dead = array();
} // }}}
// {{{ 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 $time\r\n";
if(!fwrite($sock, $cmd, strlen($cmd)))
{
$this->_dead_sock($sock);
return false;
}
$res = trim(fgets($sock)); if ($this->_debug)
printf("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)
{
if (!$this->_active)
return false; $sock = $this->get_sock($key); if (!is_resource($sock))
return false; $this->stats['get']++; $cmd = "get $key\r\n";
if (!fwrite($sock, $cmd, strlen($cmd)))
{
$this->_dead_sock($sock);
return false;
} $val = array();
$this->_load_items($sock, $val); if ($this->_debug)
foreach ($val as $k => $v)
printf("MemCache: sock %s got %s => %s\r\n", $sock, $k, $v); return $val[$key];
} // }}}
// {{{ get_multi() /**
* Get multiple keys from the server(s)
*
* @param array $keys Keys to retrieve
*
* @return array
* @access public
* get('key1') keys=array('key1','key2');
*/
function get_multi ($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;
}
$cmd .= "\r\n"; if (fwrite($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)
printf("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 (!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];
} // }}}
// }}}
// {{{ 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)
return false;
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)
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))
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)
{
$hash = 0;
for ($i=0; $i<strlen($key); $i++)
{
$hash = $hash*33 + ord($key[$i]);
} return $hash;
} // }}}
// {{{ _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 (!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)
printf("Something is borked! key %s expecting %d got %d length\n", $rkey, $len+2, $offset); unset($ret[$rkey]);
$this->_close_sock($sock);
return false;
} $ret[$rkey] = rtrim($ret[$rkey]); if ($this->_have_zlib && $flags & MEMCACHE_COMPRESSED)
$ret[$rkey] = gzuncompress($ret[$rkey]); if ($flags & MEMCACHE_SERIALIZED)
$ret[$rkey] = unserialize($ret[$rkey]); } else
{
if ($this->_debug)
print("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;
//get_sock就是去获取到memcached服务器连接
$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)
printf("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 < $len*(1 - COMPRESS_SAVINGS))
{
if ($this->_debug)
printf("client: compressing data; was %d bytes is now %d bytes\n", $len, $c_len);
$val = $c_val;
$len = $c_len;
$flags |= MEMCACHE_COMPRESSED;
}
}
if (!fwrite($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';
printf("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];
} // }}}
// }}}
// }}}
} // }}}
?>