<?php
  /**
   * Copyright (c) 2012 Bart Visscher <bartv@thisnet.nl>
   * This file is licensed under the Affero General Public License version 3 or
   * later.
   * See the COPYING-README file.
   */
  
  class OC_Cache_APC {
  	protected $prefix;
  
  	public function __construct($global = false) {
  		$this->prefix = OC_Util::getInstanceId().'/';
  		if (!$global) {
  			$this->prefix .= OC_User::getUser().'/';
  		}
  	}
  
  	/**
  	 * entries in APC gets namespaced to prevent collisions between owncloud instances and users
  	 */
  	protected function getNameSpace() {
  		return $this->prefix;
  	}
  
  	public function get($key) {
  		$result = apc_fetch($this->getNamespace().$key, $success);
  		if (!$success) {
  			return null;
  		}
  		return $result;
  	}
  
  	public function set($key, $value, $ttl=0) {
  		return apc_store($this->getNamespace().$key, $value, $ttl);
  	}
  
  	public function hasKey($key) {
  		return apc_exists($this->getNamespace().$key);
  	}
  
  	public function remove($key) {
  		return apc_delete($this->getNamespace().$key);
  	}
  
  	public function clear($prefix='') {
  		$ns = $this->getNamespace().$prefix;
  		$cache = apc_cache_info('user');
  		foreach($cache['cache_list'] as $entry) {
  			if (strpos($entry['info'], $ns) === 0) {
  				apc_delete($entry['info']);
  			}
  		}
  		return true;
  	}
  }
  if(!function_exists('apc_exists')) {
  	function apc_exists($keys)
  	{
  		$result=false;
  		apc_fetch($keys, $result);
  		return $result;
  	}
  }