text: <?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 - 2011 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;
  				}				
  			}			
  		}
  		
  		$this->_memcached = new Memcached();
  
  		foreach ($this->_memcache_conf as $name => $cache_server)
  		{
  			if ( ! array_key_exists('hostname', $cache_server))
  			{
  				$cache_server['hostname'] = $this->_default_options['default_host'];
  			}
  	
  			if ( ! array_key_exists('port', $cache_server))
  			{
  				$cache_server['port'] = $this->_default_options['default_port'];
  			}
  	
  			if ( ! array_key_exists('weight', $cache_server))
  			{
  				$cache_server['weight'] = $this->_default_options['default_weight'];
  			}
  	
  			$this->_memcached->addServer(
  					$cache_server['hostname'], $cache_server['port'], $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'))
  		{
  			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 */