pictcode

<?php

/**

 * Memcache storage engine for cache

 *

 * CakePHP(tm) : Rapid Development Framework (http://cakephp.org)

 * Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)

 *

 * Licensed under The MIT License

 * For full copyright and license information, please see the LICENSE.txt

 * Redistributions of files must retain the above copyright notice.

 *

 * @copyright     Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)

 * @link          http://cakephp.org CakePHP(tm) Project

 * @package       Cake.Cache.Engine

 * @since         CakePHP(tm) v 1.2.0.4933

 * @license       http://www.opensource.org/licenses/mit-license.php MIT License

 */

/**

 * Memcache storage engine for cache. Memcache has some limitations in the amount of

 * control you have over expire times far in the future. See MemcacheEngine::write() for

 * more information.

 *

 * @package Cake.Cache.Engine

 * @deprecated 3.0.0 You should use the Memcached adapter instead.

 */

class MemcacheEngine extends CacheEngine {

/**

 * Contains the compiled group names

 * (prefixed with the global configuration prefix)

 *

 * @var array

 */

        protected $_compiledGroupNames = array();

/**

 * Memcache wrapper.

 *

 * @var Memcache

 */

        protected $_Memcache = null;

/**

 * Settings

 *

 *  - servers = string or array of memcache servers, default => 127.0.0.1. If an

 *    array MemcacheEngine will use them as a pool.

 *  - compress = boolean, default => false

 *

 * @var array

 */

        public $settings = array();

/**

 * Initialize the Cache Engine

 *

 * Called automatically by the cache frontend

 * To reinitialize the settings call Cache::engine('EngineName', [optional] settings = array());

 *

 * @param array $settings array of setting for the engine

 * @return bool True if the engine has been successfully initialized, false if not

 */

        public function init($settings = array()) {

                if (!class_exists('Memcache')) {

                        return false;

                }

                if (!isset($settings['prefix'])) {

                        $settings['prefix'] = Inflector::slug(APP_DIR) . '_';

                }

                $settings += array(

                        'engine' => 'Memcache',

                        'servers' => array('127.0.0.1'),

                        'compress' => false,

                        'persistent' => true

                );

                parent::init($settings);

                if ($this->settings['compress']) {

                        $this->settings['compress'] = MEMCACHE_COMPRESSED;

                }

                if (is_string($this->settings['servers'])) {

                        $this->settings['servers'] = array($this->settings['servers']);

                }

                if (!isset($this->_Memcache)) {

                        $return = false;

                        $this->_Memcache = new Memcache();

                        foreach ($this->settings['servers'] as $server) {

                                list($host, $port) = $this->_parseServerString($server);

                                if ($this->_Memcache->addServer($host, $port, $this->settings['persistent'])) {

                                        $return = true;

                                }

                        }

                        return $return;

                }

                return true;

        }

/**

 * Parses the server address into the host/port. Handles both IPv6 and IPv4

 * addresses and Unix sockets

 *

 * @param string $server The server address string.

 * @return array Array containing host, port

 */

        protected function _parseServerString($server) {

                if (strpos($server, 'unix://') === 0) {

                        return array($server, 0);

                }

                if (substr($server, 0, 1) === '[') {

                        $position = strpos($server, ']:');

                        if ($position !== false) {

                                $position++;

                        }

                } else {

                        $position = strpos($server, ':');

                }

                $port = 11211;

                $host = $server;

                if ($position !== false) {

                        $host = substr($server, 0, $position);

                        $port = substr($server, $position + 1);

                }

                return array($host, $port);

        }

/**

 * Write data for key into cache. When using memcache as your cache engine

 * remember that the Memcache pecl extension does not support cache expiry times greater

 * than 30 days in the future. Any duration greater than 30 days will be treated as never expiring.

 *

 * @param string $key Identifier for the data

 * @param mixed $value Data to be cached

 * @param int $duration How long to cache the data, in seconds

 * @return bool True if the data was successfully cached, false on failure

 * @see http://php.net/manual/en/memcache.set.php

 */

        public function write($key, $value, $duration) {

                if ($duration > 30 * DAY) {

                        $duration = 0;

                }

                return $this->_Memcache->set($key, $value, $this->settings['compress'], $duration);

        }

/**

 * Read a key from the cache

 *

 * @param string $key Identifier for the data

 * @return mixed The cached data, or false if the data doesn't exist, has expired, or if there was an error fetching it

 */

        public function read($key) {

                return $this->_Memcache->get($key);

        }

/**

 * Increments the value of an integer cached key

 *

 * @param string $key Identifier for the data

 * @param int $offset How much to increment

 * @return New incremented value, false otherwise

 * @throws CacheException when you try to increment with compress = true

 */

        public function increment($key, $offset = 1) {

                if ($this->settings['compress']) {

                        throw new CacheException(

                                __d('cake_dev', 'Method %s not implemented for compressed cache in %s', 'increment()', __CLASS__)

                        );

                }

                return $this->_Memcache->increment($key, $offset);

        }

/**

 * Decrements the value of an integer cached key

 *

 * @param string $key Identifier for the data

 * @param int $offset How much to subtract

 * @return New decremented value, false otherwise

 * @throws CacheException when you try to decrement with compress = true

 */

        public function decrement($key, $offset = 1) {

                if ($this->settings['compress']) {

                        throw new CacheException(

                                __d('cake_dev', 'Method %s not implemented for compressed cache in %s', 'decrement()', __CLASS__)

                        );

                }

                return $this->_Memcache->decrement($key, $offset);

        }

/**

 * Delete a key from the cache

 *

 * @param string $key Identifier for the data

 * @return bool True if the value was successfully deleted, false if it didn't exist or couldn't be removed

 */

        public function delete($key) {

                return $this->_Memcache->delete($key);

        }

/**

 * Delete all keys from the cache

 *

 * @param bool $check If true no deletes will occur and instead CakePHP will rely

 *   on key TTL values.

 * @return bool True if the cache was successfully cleared, false otherwise

 */

        public function clear($check) {

                if ($check) {

                        return true;

                }

                foreach ($this->_Memcache->getExtendedStats('slabs', 0) as $slabs) {

                        foreach (array_keys($slabs) as $slabId) {

                                if (!is_numeric($slabId)) {

                                        continue;

                                }

                                foreach ($this->_Memcache->getExtendedStats('cachedump', $slabId, 0) as $stats) {

                                        if (!is_array($stats)) {

                                                continue;

                                        }

                                        foreach (array_keys($stats) as $key) {

                                                if (strpos($key, $this->settings['prefix']) === 0) {

                                                        $this->_Memcache->delete($key);

                                                }

                                        }

                                }

                        }

                }

                return true;

        }

/**

 * Connects to a server in connection pool

 *

 * @param string $host host ip address or name

 * @param int $port Server port

 * @return bool True if memcache server was connected

 */

        public function connect($host, $port = 11211) {

                if ($this->_Memcache->getServerStatus($host, $port) === 0) {

                        if ($this->_Memcache->connect($host, $port)) {

                                return true;

                        }

                        return false;

                }

                return true;

        }

/**

 * Returns the `group value` for each of the configured groups

 * If the group initial value was not found, then it initializes

 * the group accordingly.

 *

 * @return array

 */

        public function groups() {

                if (empty($this->_compiledGroupNames)) {

                        foreach ($this->settings['groups'] as $group) {

                                $this->_compiledGroupNames[] = $this->settings['prefix'] . $group;

                        }

                }

                $groups = $this->_Memcache->get($this->_compiledGroupNames);

                if (count($groups) !== count($this->settings['groups'])) {

                        foreach ($this->_compiledGroupNames as $group) {

                                if (!isset($groups[$group])) {

                                        $this->_Memcache->set($group, 1, false, 0);

                                        $groups[$group] = 1;

                                }

                        }

                        ksort($groups);

                }

                $result = array();

                $groups = array_values($groups);

                foreach ($this->settings['groups'] as $i => $group) {

                        $result[] = $group . $groups[$i];

                }

                return $result;

        }

/**

 * Increments the group value to simulate deletion of all keys under a group

 * old values will remain in storage until they expire.

 *

 * @param string $group The group to clear.

 * @return bool success

 */

        public function clearGroup($group) {

                return (bool)$this->_Memcache->increment($this->settings['prefix'] . $group);

        }

}