comparison cake/libs/cache/file.php @ 0:261e66bd5a0c

hg init
author Shoshi TAMAKI <shoshi@cr.ie.u-ryukyu.ac.jp>
date Sun, 24 Jul 2011 21:08:31 +0900
parents
children
comparison
equal deleted inserted replaced
-1:000000000000 0:261e66bd5a0c
1 <?php
2 /**
3 * File 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 if (!class_exists('File')) {
23 require LIBS . 'file.php';
24 }
25 /**
26 * File Storage engine for cache
27 *
28 * @todo use the File and Folder classes (if it's not a too big performance hit)
29 * @package cake
30 * @subpackage cake.cake.libs.cache
31 */
32 class FileEngine extends CacheEngine {
33
34 /**
35 * Instance of File class
36 *
37 * @var File
38 * @access protected
39 */
40 var $_File = null;
41
42 /**
43 * Settings
44 *
45 * - path = absolute path to cache directory, default => CACHE
46 * - prefix = string prefix for filename, default => cake_
47 * - lock = enable file locking on write, default => false
48 * - serialize = serialize the data, default => true
49 *
50 * @var array
51 * @see CacheEngine::__defaults
52 * @access public
53 */
54 var $settings = array();
55
56 /**
57 * True unless FileEngine::__active(); fails
58 *
59 * @var boolean
60 * @access protected
61 */
62 var $_init = true;
63
64 /**
65 * Initialize the Cache Engine
66 *
67 * Called automatically by the cache frontend
68 * To reinitialize the settings call Cache::engine('EngineName', [optional] settings = array());
69 *
70 * @param array $setting array of setting for the engine
71 * @return boolean True if the engine has been successfully initialized, false if not
72 * @access public
73 */
74 function init($settings = array()) {
75 parent::init(array_merge(
76 array(
77 'engine' => 'File', 'path' => CACHE, 'prefix'=> 'cake_', 'lock'=> false,
78 'serialize'=> true, 'isWindows' => false
79 ),
80 $settings
81 ));
82 if (!isset($this->_File)) {
83 $this->_File =& new File($this->settings['path'] . DS . 'cake');
84 }
85
86 if (DIRECTORY_SEPARATOR === '\\') {
87 $this->settings['isWindows'] = true;
88 }
89
90 $path = $this->_File->Folder->cd($this->settings['path']);
91 if ($path) {
92 $this->settings['path'] = $path;
93 }
94 return $this->__active();
95 }
96
97 /**
98 * Garbage collection. Permanently remove all expired and deleted data
99 *
100 * @return boolean True if garbage collection was succesful, false on failure
101 * @access public
102 */
103 function gc() {
104 return $this->clear(true);
105 }
106
107 /**
108 * Write data for key into cache
109 *
110 * @param string $key Identifier for the data
111 * @param mixed $data Data to be cached
112 * @param mixed $duration How long to cache the data, in seconds
113 * @return boolean True if the data was succesfully cached, false on failure
114 * @access public
115 */
116 function write($key, &$data, $duration) {
117 if ($data === '' || !$this->_init) {
118 return false;
119 }
120
121 if ($this->_setKey($key) === false) {
122 return false;
123 }
124
125 $lineBreak = "\n";
126
127 if ($this->settings['isWindows']) {
128 $lineBreak = "\r\n";
129 }
130
131 if (!empty($this->settings['serialize'])) {
132 if ($this->settings['isWindows']) {
133 $data = str_replace('\\', '\\\\\\\\', serialize($data));
134 } else {
135 $data = serialize($data);
136 }
137 }
138
139 if ($this->settings['lock']) {
140 $this->_File->lock = true;
141 }
142 $expires = time() + $duration;
143 $contents = $expires . $lineBreak . $data . $lineBreak;
144 $success = $this->_File->write($contents);
145 $this->_File->close();
146 return $success;
147 }
148
149 /**
150 * Read a key from the cache
151 *
152 * @param string $key Identifier for the data
153 * @return mixed The cached data, or false if the data doesn't exist, has expired, or if there was an error fetching it
154 * @access public
155 */
156 function read($key) {
157 if ($this->_setKey($key) === false || !$this->_init || !$this->_File->exists()) {
158 return false;
159 }
160 if ($this->settings['lock']) {
161 $this->_File->lock = true;
162 }
163 $time = time();
164 $cachetime = intval($this->_File->read(11));
165
166 if ($cachetime !== false && ($cachetime < $time || ($time + $this->settings['duration']) < $cachetime)) {
167 $this->_File->close();
168 return false;
169 }
170 $data = $this->_File->read(true);
171
172 if ($data !== '' && !empty($this->settings['serialize'])) {
173 if ($this->settings['isWindows']) {
174 $data = str_replace('\\\\\\\\', '\\', $data);
175 }
176 $data = unserialize((string)$data);
177 }
178 $this->_File->close();
179 return $data;
180 }
181
182 /**
183 * Delete a key from the cache
184 *
185 * @param string $key Identifier for the data
186 * @return boolean True if the value was successfully deleted, false if it didn't exist or couldn't be removed
187 * @access public
188 */
189 function delete($key) {
190 if ($this->_setKey($key) === false || !$this->_init) {
191 return false;
192 }
193 return $this->_File->delete();
194 }
195
196 /**
197 * Delete all values from the cache
198 *
199 * @param boolean $check Optional - only delete expired cache items
200 * @return boolean True if the cache was succesfully cleared, false otherwise
201 * @access public
202 */
203 function clear($check) {
204 if (!$this->_init) {
205 return false;
206 }
207 $dir = dir($this->settings['path']);
208 if ($check) {
209 $now = time();
210 $threshold = $now - $this->settings['duration'];
211 }
212 $prefixLength = strlen($this->settings['prefix']);
213 while (($entry = $dir->read()) !== false) {
214 if (substr($entry, 0, $prefixLength) !== $this->settings['prefix']) {
215 continue;
216 }
217 if ($this->_setKey($entry) === false) {
218 continue;
219 }
220 if ($check) {
221 $mtime = $this->_File->lastChange();
222
223 if ($mtime === false || $mtime > $threshold) {
224 continue;
225 }
226
227 $expires = $this->_File->read(11);
228 $this->_File->close();
229
230 if ($expires > $now) {
231 continue;
232 }
233 }
234 $this->_File->delete();
235 }
236 $dir->close();
237 return true;
238 }
239
240 /**
241 * Get absolute file for a given key
242 *
243 * @param string $key The key
244 * @return mixed Absolute cache file for the given key or false if erroneous
245 * @access private
246 */
247 function _setKey($key) {
248 $this->_File->Folder->cd($this->settings['path']);
249 if ($key !== $this->_File->name) {
250 $this->_File->name = $key;
251 $this->_File->path = null;
252 }
253 if (!$this->_File->Folder->inPath($this->_File->pwd(), true)) {
254 return false;
255 }
256 }
257
258 /**
259 * Determine is cache directory is writable
260 *
261 * @return boolean
262 * @access private
263 */
264 function __active() {
265 if ($this->_init && !is_writable($this->settings['path'])) {
266 $this->_init = false;
267 trigger_error(sprintf(__('%s is not writable', true), $this->settings['path']), E_USER_WARNING);
268 return false;
269 }
270 return true;
271 }
272 }