CI system/libraries/Cache/drivers/memcached.php 兼容 memcache,memcached扩展

xywuyiba7

　　本来CI不支持memcache扩展，只支持memcahed 扩展，修改成
　　如果php module 加载 memcached 扩展，直接创建 memcahed 对象
　　如果php module 没加载 memcached 扩展，加载了 memcahe 扩展 ，直接创建 memcache 对象
　　虽然改成不是很大，但是解决了CI, memcache,memcached兼容问题~

代码如下：


<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');
/**
* CodeIgniter
*
* An open source application development framework for PHP 4.3.2 or newer
*
* @package  CodeIgniter
* @author  ExpressionEngine Dev Team
* @copyright Copyright (c) 2006 - 2012 EllisLab, Inc.
* @license  http://codeigniter.com/user_guide/license.html
* @link  http://codeigniter.com
* @since  Version 2.0
* @filesource
*/
// ------------------------------------------------------------------------
/**
* CodeIgniter Memcached Caching Class
*
* @package  CodeIgniter
* @subpackage Libraries
* @category Core
* @author  ExpressionEngine Dev Team
* @link  
*/
class CI_Cache_memcached extends CI_Driver {
private $_memcached; // Holds the memcached object
protected $_memcache_conf  = array(
'default' => array(
'default_host'  => '127.0.0.1',
'default_port'  => 11211,
'default_weight' => 1
)
);
// ------------------------------------------------------------------------
/**
* Fetch from cache
*
* @param  mixed  unique key id
* @return  mixed  data on success/false on failure
*/
public function get($id)
{
$data = $this->_memcached->get($id);
return (is_array($data)) ? $data[0] : FALSE;
}
// ------------------------------------------------------------------------
/**
* Save
*
* @param  string  unique identifier
* @param  mixed  data being cached
* @param  int   time to live
* @return  boolean  true on success, false on failure
*/
public function save($id, $data, $ttl = 60)
{
if (get_class($this->_memcached) == 'Memcached')
{
return $this->_memcached->set($id, array($data, time(), $ttl), $ttl);
}
else if (get_class($this->_memcached) == 'Memcache')
{
return $this->_memcached->set($id, array($data, time(), $ttl), 0, $ttl);
}
return FALSE;
}
// ------------------------------------------------------------------------
/**
* Delete from Cache
*
* @param  mixed  key to be deleted.
* @return  boolean  true on success, false on failure
*/
public function delete($id)
{
return $this->_memcached->delete($id);
}
// ------------------------------------------------------------------------
/**
* Clean the Cache
*
* @return  boolean  false on failure/true on success
*/
public function clean()
{
return $this->_memcached->flush();
}
// ------------------------------------------------------------------------
/**
* Cache Info
*
* @param  null  type not supported in memcached
* @return  mixed   array on success, false on failure
*/
public function cache_info($type = NULL)
{
return $this->_memcached->getStats();
}
// ------------------------------------------------------------------------
/**
* Get Cache Metadata
*
* @param  mixed  key to get cache metadata on
* @return  mixed  FALSE on failure, array on success.
*/
public function get_metadata($id)
{
$stored = $this->_memcached->get($id);
if (count($stored) !== 3)
{
return FALSE;
}
list($data, $time, $ttl) = $stored;
return array(
'expire' => $time + $ttl,
'mtime'  => $time,
'data'  => $data
);
}
// ------------------------------------------------------------------------
/**
* Setup memcached.
*/
private function _setup_memcached()
{
// Try to load memcached server info from the config file.
$CI =& get_instance();
if ($CI->config->load('memcached', TRUE, TRUE))
{
if (is_array($CI->config->config['memcached']))
{
$this->_memcache_conf = NULL;
foreach ($CI->config->config['memcached'] as $name => $conf)
{
$this->_memcache_conf[$name] = $conf;
}   
}   
}
if (extension_loaded('memcached')){
$this->_memcached = new Memcached();
}else{
$this->_memcached = new Memcache();
}

foreach ($this->_memcache_conf as $name => $cache_server)
{
if ( ! array_key_exists('hostname', $cache_server))
{
// $cache_server['hostname'] = $this->_default_options['default_host']; //坑爹的原代码,没有_default_options属性
$cache_server['hostname'] = $this->_memcache_conf['default']['default_host'];
}
if ( ! array_key_exists('port', $cache_server))
{
// $cache_server['port'] = $this->_default_options['default_port'];//坑爹的原代码,没有_default_options属性
$cache_server['port'] = $this->_memcache_conf['default']['default_port'];
}
if ( ! array_key_exists('weight', $cache_server))
{
//  $cache_server['weight'] = $this->_default_options['default_weight'];//坑爹的原代码,没有_default_options属性
$cache_server['weight'] = $this->_memcache_conf['default']['default_weight'];
}
//导 致如果不配置 config/memcache.php文件，执行 到$this->_memcached->addServer($cache_server['hostname'],$cache_server['port']); 出错（因为此时语句，相当于
$this->_memcached->addServer(‘’,'');然后机器木反应了~
if (extension_loaded('memcached')){
$this->_memcached->addServer(
$cache_server['hostname'], $cache_server['port'], $cache_server['weight']
);
}else{
$this->_memcached->addServer($cache_server['hostname'],$cache_server['port'],TRUE, $cache_server['weight']);
}
}
}
// ------------------------------------------------------------------------

/**
* Is supported
*
* Returns FALSE if memcached is not supported on the system.
* If it is, we setup the memcached object & return TRUE
*/
public function is_supported()
{
if ( !extension_loaded('memcached') && !extension_loaded('memcache'))
{
log_message('error', 'The Memcached Extension must be loaded to use Memcached Cache.');
return FALSE;
}
$this->_setup_memcached();
return TRUE;
}
// ------------------------------------------------------------------------

}
// End Class
/* End of file Cache_memcached.php */
/* Location: ./system/libraries/Cache/drivers/Cache_memcached.php */