cake/libs/cache/apc.php

1 <?php
2 /**
3 * APC storage engine for cache.
4 *
5 *
6 * PHP versions 4 and 5
7 *
8 * CakePHP(tm) : Rapid Development Framework (http://cakephp.org)
9 * Copyright 2005-2010, Cake Software Foundation, Inc. (http://cakefoundation.org)
10 *
11 * Licensed under The MIT License
12 * Redistributions of files must retain the above copyright notice.
13 *
14 * @copyright Copyright 2005-2010, Cake Software Foundation, Inc. (http://cakefoundation.org)
15 * @link http://cakephp.org CakePHP(tm) Project
16 * @package cake
17 * @subpackage cake.cake.libs.cache
18 * @since CakePHP(tm) v 1.2.0.4933
19 * @license MIT License (http://www.opensource.org/licenses/mit-license.php)
20 */
21  
22 /**
23 * APC storage engine for cache
24 *
25 * @package cake
26 * @subpackage cake.cake.libs.cache
27 */
28 class ApcEngine extends CacheEngine {
29  
30 /**
31 * Initialize the Cache Engine
32 *
33 * Called automatically by the cache frontend
34 * To reinitialize the settings call Cache::engine('EngineName', [optional] settings = array());
35 *
36 * @param array $setting array of setting for the engine
37 * @return boolean True if the engine has been successfully initialized, false if not
38 * @see CacheEngine::__defaults
39 * @access public
40 */
41 function init($settings = array()) {
42 parent::init(array_merge(array('engine' => 'Apc', 'prefix' => Inflector::slug(APP_DIR) . '_'), $settings));
43 return function_exists('apc_cache_info');
44 }
45  
46 /**
47 * Write data for key into cache
48 *
49 * @param string $key Identifier for the data
50 * @param mixed $value Data to be cached
51 * @param integer $duration How long to cache the data, in seconds
52 * @return boolean True if the data was succesfully cached, false on failure
53 * @access public
54 */
55 function write($key, &$value, $duration) {
56 $expires = time() + $duration;
57 apc_store($key.'_expires', $expires, $duration);
58 return apc_store($key, $value, $duration);
59 }
60  
61 /**
62 * Read a key from the cache
63 *
64 * @param string $key Identifier for the data
65 * @return mixed The cached data, or false if the data doesn't exist, has expired, or if there was an error fetching it
66 * @access public
67 */
68 function read($key) {
69 $time = time();
70 $cachetime = intval(apc_fetch($key.'_expires'));
71 if ($cachetime < $time || ($time + $this->settings['duration']) < $cachetime) {
72 return false;
73 }
74 return apc_fetch($key);
75 }
76  
77 /**
78 * Increments the value of an integer cached key
79 *
80 * @param string $key Identifier for the data
81 * @param integer $offset How much to increment
82 * @param integer $duration How long to cache the data, in seconds
83 * @return New incremented value, false otherwise
84 * @access public
85 */
86 function increment($key, $offset = 1) {
87 return apc_inc($key, $offset);
88 }
89  
90 /**
91 * Decrements the value of an integer cached key
92 *
93 * @param string $key Identifier for the data
94 * @param integer $offset How much to substract
95 * @param integer $duration How long to cache the data, in seconds
96 * @return New decremented value, false otherwise
97 * @access public
98 */
99 function decrement($key, $offset = 1) {
100 return apc_dec($key, $offset);
101 }
102  
103 /**
104 * Delete a key from the cache
105 *
106 * @param string $key Identifier for the data
107 * @return boolean True if the value was succesfully deleted, false if it didn't exist or couldn't be removed
108 * @access public
109 */
110 function delete($key) {
111 return apc_delete($key);
112 }
113  
114 /**
115 * Delete all keys from the cache
116 *
117 * @return boolean True if the cache was succesfully cleared, false otherwise
118 * @access public
119 */
120 function clear() {
121 return apc_clear_cache('user');
122 }
123 }
124  
125