Viewing file:  Memcached.php (6.22 KB) -rw-rw-rw-
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
<?php
/**
* PECL Memcached class
*/
if (!defined('W3TC')) {
die();
}
w3_require_once(W3TC_LIB_W3_DIR . '/Cache/Base.php');
/**
* Class W3_Cache_Memcached
*/
class W3_Cache_Memcached extends W3_Cache_Base {
/**
* Memcache object
*
* @var Memcache
*/
private $_memcache = null;
/*
* Used for faster flushing
*
* @var integer $_key_version
*/
private $_key_version = array();
/**
* constructor
*
* @param array $config
*/
function __construct($config) {
parent::__construct($config);
$this->_memcache = new Memcache();
if (!empty($config['servers'])) {
$persistant = isset($config['persistant']) ? (boolean) $config['persistant'] : false;
foreach ((array) $config['servers'] as $server) {
if (substr($server, 0, 5) == 'unix:')
$this->_memcache->addServer(trim($server), 0, $persistant);
else {
list($ip, $port) = explode(':', $server);
$this->_memcache->addServer(trim($ip), (integer) trim($port), $persistant);
}
}
} else {
return false;
}
if (!empty($config['compress_threshold'])) {
$this->_memcache->setCompressThreshold((integer) $config['compress_threshold']);
}
return true;
}
/**
* Adds data
*
* @param string $key
* @param mixed $var
* @param integer $expire
* @param string $group Used to differentiate between groups of cache values
* @return boolean
*/
function add($key, &$var, $expire = 0, $group = '0') {
return $this->set($key, $var, $expire, $group);
}
/**
* Sets data
*
* @param string $key
* @param mixed $var
* @param integer $expire
* @param string $group Used to differentiate between groups of cache values
* @return boolean
*/
function set($key, $var, $expire = 0, $group = '0') {
$key = $this->get_item_key($key);
$var['key_version'] = $this->_get_key_version($group);
return @$this->_memcache->set($key . '_' . $this->_blog_id, $var,
false, $expire);
}
/**
* Returns data
*
* @param string $key
* @param string $group Used to differentiate between groups of cache values
* @return mixed
*/
function get_with_old($key, $group = '0') {
$has_old_data = false;
$key = $this->get_item_key($key);
$v = @$this->_memcache->get($key . '_' . $this->_blog_id);
if (!is_array($v) || !isset($v['key_version']))
return array(null, $has_old_data);
$key_version = $this->_get_key_version($group);
if ($v['key_version'] == $key_version)
return array($v, $has_old_data);
if ($v['key_version'] > $key_version) {
$this->_set_key_version($v['key_version'], $group);
return array($v, $has_old_data);
}
// key version is old
if (!$this->_use_expired_data)
return array(null, $has_old_data);
// if we have expired data - update it for future use and let
// current process recalculate it
$expires_at = isset($v['expires_at']) ? $v['expires_at'] : null;
if ($expires_at == null || time() > $expires_at) {
$v['expires_at'] = time() + 30;
@$this->_memcache->set($key . '_' . $this->_blog_id, $v, false, 0);
$has_old_data = true;
return array(null, $has_old_data);
}
// return old version
return array($v, $has_old_data);
}
/**
* Replaces data
*
* @param string $key
* @param mixed $var
* @param integer $expire
* @param string $group Used to differentiate between groups of cache values
* @return boolean
*/
function replace($key, &$var, $expire = 0, $group = '0') {
return $this->set($key, $var, $expire, $group);
}
/**
* Deletes data
*
* @param string $key
* @param string $group
* @return boolean
*/
function delete($key, $group = '') {
$key = $this->get_item_key($key);
if ($this->_use_expired_data) {
$v = @$this->_memcache->get($key . '_' . $this->_blog_id);
if (is_array($v)) {
$v['key_version'] = 0;
@$this->_memcache->set($key . '_' . $this->_blog_id, $v, false, 0);
return true;
}
}
return @$this->_memcache->delete($key . '_' . $this->_blog_id, 0);
}
/**
* Key to delete, deletes .old and primary if exists.
* @param $key
* @return bool
*/
function hard_delete($key) {
$key = $this->get_item_key($key);
return @$this->_memcache->delete($key . '_' . $this->_blog_id, 0);
}
/**
* Flushes all data
*
* @param string $group Used to differentiate between groups of cache values
* @return boolean
*/
function flush($group = '0') {
$this->_get_key_version($group); // initialize $this->_key_version
$this->_key_version[$group]++;
$this->_set_key_version($this->_key_version[$group], $group);
return true;
}
/**
* Checks if engine can function properly in this environment
* @return bool
*/
public function available() {
return class_exists('Memcache');
}
/**
* Returns key version
*
* @param string $group Used to differentiate between groups of cache values
* @return integer
*/
private function _get_key_version($group = '0') {
if (!isset($this->_key_version[$group]) || $this->_key_version[$group] <= 0) {
$v = @$this->_memcache->get($this->_get_key_version_key($group));
$v = intval($v);
$this->_key_version[$group] = ($v > 0 ? $v : 1);
}
return $this->_key_version[$group];
}
/**
* Sets new key version
*
* @param $v
* @param string $group Used to differentiate between groups of cache values
* @return boolean
*/
private function _set_key_version($v, $group = '0') {
@$this->_memcache->set($this->_get_key_version_key($group), $v, false, 0);
}
}
|