Apc.php

Go to the documentation of this file.

<?php
#require_once 'Zend/Cache/Backend/ExtendedInterface.php';

#require_once 'Zend/Cache/Backend.php';


class Zend_Cache_Backend_Apc extends Zend_Cache_Backend implements Zend_Cache_Backend_ExtendedInterface
{
    const TAGS_UNSUPPORTED_BY_CLEAN_OF_APC_BACKEND = 'Zend_Cache_Backend_Apc::clean() : tags are unsupported by the Apc backend';
    const TAGS_UNSUPPORTED_BY_SAVE_OF_APC_BACKEND =  'Zend_Cache_Backend_Apc::save() : tags are unsupported by the Apc backend';

    public function __construct(array $options = array())
    {
        if (!extension_loaded('apc')) {
            Zend_Cache::throwException('The apc extension must be loaded for using this backend !');
        }
        parent::__construct($options);
    }

    public function load($id, $doNotTestCacheValidity = false)
    {
        $tmp = apc_fetch($id);
        if (is_array($tmp)) {
            return $tmp[0];
        }
        return false;
    }

    public function test($id)
    {
        $tmp = apc_fetch($id);
        if (is_array($tmp)) {
            return $tmp[1];
        }
        return false;
    }

    public function save($data, $id, $tags = array(), $specificLifetime = false)
    {
        $lifetime = $this->getLifetime($specificLifetime);
        $result = apc_store($id, array($data, time(), $lifetime), $lifetime);
        if (count($tags) > 0) {
            $this->_log(self::TAGS_UNSUPPORTED_BY_SAVE_OF_APC_BACKEND);
        }
        return $result;
    }

    public function remove($id)
    {
        return apc_delete($id);
    }

    public function clean($mode = Zend_Cache::CLEANING_MODE_ALL, $tags = array())
    {
        switch ($mode) {
            case Zend_Cache::CLEANING_MODE_ALL:
                return apc_clear_cache('user');
                break;
            case Zend_Cache::CLEANING_MODE_OLD:
                $this->_log("Zend_Cache_Backend_Apc::clean() : CLEANING_MODE_OLD is unsupported by the Apc backend");
                break;
            case Zend_Cache::CLEANING_MODE_MATCHING_TAG:
            case Zend_Cache::CLEANING_MODE_NOT_MATCHING_TAG:
            case Zend_Cache::CLEANING_MODE_MATCHING_ANY_TAG:
                $this->_log(self::TAGS_UNSUPPORTED_BY_CLEAN_OF_APC_BACKEND);
                break;
            default:
                Zend_Cache::throwException('Invalid mode for clean() method');
                break;
        }
    }

    public function isAutomaticCleaningAvailable()
    {
        return false;
    }

    public function getFillingPercentage()
    {
        $mem = apc_sma_info(true);
        $memSize    = $mem['num_seg'] * $mem['seg_size'];
        $memAvailable= $mem['avail_mem'];
        $memUsed = $memSize - $memAvailable;
        if ($memSize == 0) {
            Zend_Cache::throwException('can\'t get apc memory size');
        }
        if ($memUsed > $memSize) {
            return 100;
        }
        return ((int) (100. * ($memUsed / $memSize)));
    }

    public function getTags()
    {
        $this->_log(self::TAGS_UNSUPPORTED_BY_SAVE_OF_APC_BACKEND);
        return array();
    }

    public function getIdsMatchingTags($tags = array())
    {
        $this->_log(self::TAGS_UNSUPPORTED_BY_SAVE_OF_APC_BACKEND);
        return array();
    }

    public function getIdsNotMatchingTags($tags = array())
    {
        $this->_log(self::TAGS_UNSUPPORTED_BY_SAVE_OF_APC_BACKEND);
        return array();
    }

    public function getIdsMatchingAnyTags($tags = array())
    {
        $this->_log(self::TAGS_UNSUPPORTED_BY_SAVE_OF_APC_BACKEND);
        return array();
    }

    public function getIds()
    {
        $ids      = array();
        $iterator = new APCIterator('user', null, APC_ITER_KEY);
        foreach ($iterator as $item) {
            $ids[] = $item['key'];
        }

        return $ids;
    }

    public function getMetadatas($id)
    {
        $tmp = apc_fetch($id);
        if (is_array($tmp)) {
            $data = $tmp[0];
            $mtime = $tmp[1];
            if (!isset($tmp[2])) {
                // because this record is only with 1.7 release
                // if old cache records are still there...
                return false;
            }
            $lifetime = $tmp[2];
            return array(
                'expire' => $mtime + $lifetime,
                'tags' => array(),
                'mtime' => $mtime
            );
        }
        return false;
    }

    public function touch($id, $extraLifetime)
    {
        $tmp = apc_fetch($id);
        if (is_array($tmp)) {
            $data = $tmp[0];
            $mtime = $tmp[1];
            if (!isset($tmp[2])) {
                // because this record is only with 1.7 release
                // if old cache records are still there...
                return false;
            }
            $lifetime = $tmp[2];
            $newLifetime = $lifetime - (time() - $mtime) + $extraLifetime;
            if ($newLifetime <=0) {
                return false;
            }
            apc_store($id, array($data, time(), $newLifetime), $newLifetime);
            return true;
        }
        return false;
    }

    public function getCapabilities()
    {
        return array(
            'automatic_cleaning' => false,
            'tags' => false,
            'expired_read' => false,
            'priority' => false,
            'infinite_lifetime' => false,
            'get_list' => true
        );
    }

}