Cache_Lite::_setRefreshTime()   A
last analyzed

Complexity

Conditions 2
Paths 2

Size

Total Lines 8
Code Lines 5

Duplication

Lines 0
Ratio 0 %

Importance

Changes 0
Metric Value
dl 0
loc 8
rs 9.4285
c 0
b 0
f 0
cc 2
eloc 5
nc 2
nop 0
1
<?php
2
3
/**
4
* Fast, light and safe Cache Class
5
*
6
* Cache_Lite is a fast, light and safe cache system. It's optimized
7
* for file containers. It is fast and safe (because it uses file
8
* locking and/or anti-corruption tests).
9
*
10
* There are some examples in the 'docs/examples' file
11
* Technical choices are described in the 'docs/technical' file
12
*
13
* Memory Caching is from an original idea of
14
* Mike BENOIT <[email protected]>
15
*
16
* Nota : A chinese documentation (thanks to RainX <[email protected]>) is
17
* available at :
18
* http://rainx.phpmore.com/manual/cache_lite.html
19
*
20
* @package Cache_Lite
21
* @category Caching
22
* @version $Id: Lite.php,v 1.45 2006/06/03 08:10:33 fab Exp $
23
* @author Fabien MARTY <[email protected]>
24
*/
25
26
define('CACHE_LITE_ERROR_RETURN', 1);
27
define('CACHE_LITE_ERROR_DIE', 8);
28
29
class Cache_Lite
30
{
31
32
    // --- Private properties ---
33
34
    /**
35
    * Directory where to put the cache files
36
    * (make sure to add a trailing slash)
37
    *
38
    * @var string $_cacheDir
39
    */
40
    var $_cacheDir = '/tmp/';
41
42
    /**
43
    * Enable / disable caching
44
    *
45
    * (can be very usefull for the debug of cached scripts)
46
    *
47
    * @var boolean $_caching
48
    */
49
    var $_caching = true;
50
51
    /**
52
    * Cache lifetime (in seconds)
53
    *
54
    * If null, the cache is valid forever.
55
    *
56
    * @var int $_lifeTime
57
    */
58
    var $_lifeTime = 3600;
59
60
    /**
61
    * Enable / disable fileLocking
62
    *
63
    * (can avoid cache corruption under bad circumstances)
64
    *
65
    * @var boolean $_fileLocking
66
    */
67
    var $_fileLocking = true;
68
69
    /**
70
    * Timestamp of the last valid cache
71
    *
72
    * @var int $_refreshTime
73
    */
74
    var $_refreshTime;
75
76
    /**
77
    * File name (with path)
78
    *
79
    * @var string $_file
80
    */
81
    var $_file;
82
83
    /**
84
    * File name (without path)
85
    *
86
    * @var string $_fileName
87
    */
88
    var $_fileName;
89
90
    /**
91
    * Enable / disable write control (the cache is read just after writing to detect corrupt entries)
92
    *
93
    * Enable write control will lightly slow the cache writing but not the cache reading
94
    * Write control can detect some corrupt cache files but maybe it's not a perfect control
95
    *
96
    * @var boolean $_writeControl
97
    */
98
    var $_writeControl = true;
99
100
    /**
101
    * Enable / disable read control
102
    *
103
    * If enabled, a control key is embeded in cache file and this key is compared with the one
104
    * calculated after the reading.
105
    *
106
    * @var boolean $_writeControl
107
    */
108
    var $_readControl = false;
109
110
    /**
111
    * Type of read control (only if read control is enabled)
112
    *
113
    * Available values are :
114
    * 'md5' for a md5 hash control (best but slowest)
115
    * 'crc32' for a crc32 hash control (lightly less safe but faster, better choice)
116
    * 'strlen' for a length only test (fastest)
117
    *
118
    * @var boolean $_readControlType
119
    */
120
    var $_readControlType = 'crc32';
121
122
    /**
123
    * Pear error mode (when raiseError is called)
124
    *
125
    * (see PEAR doc)
126
    *
127
    * @see setToDebug()
128
    * @var int $_pearErrorMode
129
    */
130
    var $_pearErrorMode = CACHE_LITE_ERROR_RETURN;
131
132
    /**
133
    * Current cache id
134
    *
135
    * @var string $_id
136
    */
137
    var $_id;
138
139
    /**
140
    * Current cache group
141
    *
142
    * @var string $_group
143
    */
144
    var $_group;
145
146
    /**
147
    * Enable / Disable "Memory Caching"
148
    *
149
    * NB : There is no lifetime for memory caching !
150
    *
151
    * @var boolean $_memoryCaching
152
    */
153
    var $_memoryCaching = false;
154
155
    /**
156
    * Enable / Disable "Only Memory Caching"
157
    * (be carefull, memory caching is "beta quality")
158
    *
159
    * @var boolean $_onlyMemoryCaching
160
    */
161
    var $_onlyMemoryCaching = false;
162
163
    /**
164
    * Memory caching array
165
    *
166
    * @var array $_memoryCachingArray
167
    */
168
    var $_memoryCachingArray = array();
169
170
    /**
171
    * Memory caching counter
172
    *
173
    * @var int $memoryCachingCounter
174
    */
175
    var $_memoryCachingCounter = 0;
176
177
    /**
178
    * Memory caching limit
179
    *
180
    * @var int $memoryCachingLimit
181
    */
182
    var $_memoryCachingLimit = 1000;
183
184
    /**
185
    * File Name protection
186
    *
187
    * if set to true, you can use any cache id or group name
188
    * if set to false, it can be faster but cache ids and group names
189
    * will be used directly in cache file names so be carefull with
190
    * special characters...
191
    *
192
    * @var boolean $fileNameProtection
193
    */
194
    var $_fileNameProtection = true;
195
196
    /**
197
    * Enable / disable automatic serialization
198
    *
199
    * it can be used to save directly datas which aren't strings
200
    * (but it's slower)
201
    *
202
    * @var boolean $_serialize
203
    */
204
    var $_automaticSerialization = false;
205
206
    /**
207
    * Disable / Tune the automatic cleaning process
208
    *
209
    * The automatic cleaning process destroy too old (for the given life time)
210
    * cache files when a new cache file is written.
211
    * 0               => no automatic cache cleaning
212
    * 1               => systematic cache cleaning
213
    * x (integer) > 1 => automatic cleaning randomly 1 times on x cache write
214
    *
215
    * @var int $_automaticCleaning
216
    */
217
    var $_automaticCleaningFactor = 0;
218
219
    /**
220
    * Nested directory level
221
    *
222
    * Set the hashed directory structure level. 0 means "no hashed directory
223
    * structure", 1 means "one level of directory", 2 means "two levels"...
224
    * This option can speed up Cache_Lite only when you have many thousands of
225
    * cache file. Only specific benchs can help you to choose the perfect value
226
    * for you. Maybe, 1 or 2 is a good start.
227
    *
228
    * @var int $_hashedDirectoryLevel
229
    */
230
    var $_hashedDirectoryLevel = 0;
231
232
    /**
233
    * Umask for hashed directory structure
234
    *
235
    * @var int $_hashedDirectoryUmask
236
    */
237
    var $_hashedDirectoryUmask = 0770;
238
239
    /**
240
     * API break for error handling in CACHE_LITE_ERROR_RETURN mode
241
     *
242
     * In CACHE_LITE_ERROR_RETURN mode, error handling was not good because
243
     * for example save() method always returned a boolean (a PEAR_Error object
244
     * would be better in CACHE_LITE_ERROR_RETURN mode). To correct this without
245
     * breaking the API, this option (false by default) can change this handling.
246
     *
247
     * @var boolean
248
     */
249
    var $_errorHandlingAPIBreak = false;
250
251
    // --- Public methods ---
252
253
    /**
254
    * Constructor
255
    *
256
    * $options is an assoc. Available options are :
257
    * $options = array(
258
    *     'cacheDir' => directory where to put the cache files (string),
259
    *     'caching' => enable / disable caching (boolean),
260
    *     'lifeTime' => cache lifetime in seconds (int),
261
    *     'fileLocking' => enable / disable fileLocking (boolean),
262
    *     'writeControl' => enable / disable write control (boolean),
263
    *     'readControl' => enable / disable read control (boolean),
264
    *     'readControlType' => type of read control 'crc32', 'md5', 'strlen' (string),
265
    *     'pearErrorMode' => pear error mode (when raiseError is called) (cf PEAR doc) (int),
266
    *     'memoryCaching' => enable / disable memory caching (boolean),
267
    *     'onlyMemoryCaching' => enable / disable only memory caching (boolean),
268
    *     'memoryCachingLimit' => max nbr of records to store into memory caching (int),
269
    *     'fileNameProtection' => enable / disable automatic file name protection (boolean),
270
    *     'automaticSerialization' => enable / disable automatic serialization (boolean),
271
    *     'automaticCleaningFactor' => distable / tune automatic cleaning process (int),
272
    *     'hashedDirectoryLevel' => level of the hashed directory system (int),
273
    *     'hashedDirectoryUmask' => umask for hashed directory structure (int),
274
    *     'errorHandlingAPIBreak' => API break for better error handling ? (boolean)
275
    * );
276
    *
277
    * @param array $options options
278
    * @access public
279
    */
280
    function __construct($options = array(NULL))
281
    {
282
        foreach($options as $key => $value) {
283
            $this->setOption($key, $value);
284
        }
285
    }
286
287
    /**
288
    * Generic way to set a Cache_Lite option
289
    *
290
    * see Cache_Lite constructor for available options
291
    *
292
    * @var string $name name of the option
293
    * @var mixed $value value of the option
294
    * @access public
295
    */
296
    function setOption($name, $value)
297
    {
298
        $availableOptions = array('errorHandlingAPIBreak', 'hashedDirectoryUmask', 'hashedDirectoryLevel', 'automaticCleaningFactor', 'automaticSerialization', 'fileNameProtection', 'memoryCaching', 'onlyMemoryCaching', 'memoryCachingLimit', 'cacheDir', 'caching', 'lifeTime', 'fileLocking', 'writeControl', 'readControl', 'readControlType', 'pearErrorMode');
299
        if (in_array($name, $availableOptions)) {
300
            $property = '_'.$name;
301
            $this->$property = $value;
302
        }
303
    }
304
305
    /**
306
    * Test if a cache is available and (if yes) return it
307
    *
308
    * @param string $id cache id
309
    * @param string $group name of the cache group
310
    * @param boolean $doNotTestCacheValidity if set to true, the cache validity won't be tested
311
    * @return string data of the cache (else : false)
312
    * @access public
313
    */
314
    function get($id, $group = 'default', $doNotTestCacheValidity = false)
315
    {
316
        $this->_id = $id;
317
        $this->_group = $group;
318
        $data = false;
319
        if ($this->_caching) {
320
            $this->_setRefreshTime();
321
            $this->_setFileName($id, $group);
322
            clearstatcache();
323
            if ($this->_memoryCaching) {
324
                if (isset($this->_memoryCachingArray[$this->_file])) {
325
                    if ($this->_automaticSerialization) {
326
                        return unserialize($this->_memoryCachingArray[$this->_file]);
327
                    }
328
                    return $this->_memoryCachingArray[$this->_file];
329
                }
330
                if ($this->_onlyMemoryCaching) {
331
                    return false;
332
                }
333
            }
334
            if (($doNotTestCacheValidity) || (is_null($this->_refreshTime))) {
335
            	if (file_exists($this->_file)) {
336
                    $data = $this->_read();
337
                }
338
            } else {
339
            	if ((file_exists($this->_file)) && (@filemtime($this->_file) > $this->_refreshTime)) {
340
                    $data = $this->_read();
341
                }
342
            }
343
            if (($data) and ($this->_memoryCaching)) {
344
                $this->_memoryCacheAdd($data);
345
            }
346
            if (($this->_automaticSerialization) and (is_string($data))) {
347
                $data = unserialize($data);
348
            }
349
            return $data;
350
        }
351
        return false;
352
    }
353
354
    /**
355
    * Save some data in a cache file
356
    *
357
    * @param string $data data to put in cache (can be another type than strings if automaticSerialization is on)
358
    * @param string $id cache id
359
    * @param string $group name of the cache group
360
    * @return boolean true if no problem (else : false or a PEAR_Error object)
361
    * @access public
362
    */
363
    function save($data, $id = NULL, $group = 'default')
364
    {
365
        if ($this->_caching) {
366
            if ($this->_automaticSerialization) {
367
                $data = serialize($data);
368
            }
369
            if (isset($id)) {
370
                $this->_setFileName($id, $group);
371
            }
372
            if ($this->_memoryCaching) {
373
                $this->_memoryCacheAdd($data);
374
                if ($this->_onlyMemoryCaching) {
375
                    return true;
376
                }
377
            }
378
            if ($this->_automaticCleaningFactor>0) {
379
                $rand = rand(1, $this->_automaticCleaningFactor);
380
                if ($rand==1) {
381
                    $this->clean(false, 'old');
382
                }
383
            }
384
            if ($this->_writeControl) {
385
                $res = $this->_writeAndControl($data);
386
                if (is_bool($res)) {
387
                    if ($res) {
388
                        return true;
389
                    }
390
                    // if $res if false, we need to invalidate the cache
391
                    @touch($this->_file, time() - 2*abs($this->_lifeTime));
392
                    return false;
393
                }
394
            } else {
395
                $res = $this->_write($data);
396
            }
397
            if (is_object($res)) {
398
	        	// $res is a PEAR_Error object
399
                if (!($this->_errorHandlingAPIBreak)) {
400
	                return false; // we return false (old API)
401
	            }
402
	        }
403
            return $res;
404
        }
405
        return false;
406
    }
407
408
    /**
409
    * Remove a cache file
410
    *
411
    * @param string $id cache id
412
    * @param string $group name of the cache group
413
    * @return boolean true if no problem
414
    * @access public
415
    */
416
    function remove($id, $group = 'default')
417
    {
418
        $this->_setFileName($id, $group);
419
        if ($this->_memoryCaching) {
420
            if (isset($this->_memoryCachingArray[$this->_file])) {
421
                unset($this->_memoryCachingArray[$this->_file]);
422
                $this->_memoryCachingCounter = $this->_memoryCachingCounter - 1;
423
            }
424
            if ($this->_onlyMemoryCaching) {
425
                return true;
426
            }
427
        }
428
        return $this->_unlink($this->_file);
429
    }
430
431
    /**
432
    * Clean the cache
433
    *
434
    * if no group is specified all cache files will be destroyed
435
    * else only cache files of the specified group will be destroyed
436
    *
437
    * @param string $group name of the cache group
438
    * @param string $mode flush cache mode : 'old', 'ingroup', 'notingroup',
439
    *                                        'callback_myFunction'
440
    * @return boolean true if no problem
441
    * @access public
442
    */
443
    function clean($group = false, $mode = 'ingroup')
444
    {
445
        return $this->_cleanDir($this->_cacheDir, $group, $mode);
446
    }
447
448
    /**
449
    * Set to debug mode
450
    *
451
    * When an error is found, the script will stop and the message will be displayed
452
    * (in debug mode only).
453
    *
454
    * @access public
455
    */
456
    function setToDebug()
457
    {
458
        $this->setOption('pearErrorMode', CACHE_LITE_ERROR_DIE);
459
    }
460
461
    /**
462
    * Set a new life time
463
    *
464
    * @param int $newLifeTime new life time (in seconds)
465
    * @access public
466
    */
467
    function setLifeTime($newLifeTime)
468
    {
469
        $this->_lifeTime = $newLifeTime;
470
        $this->_setRefreshTime();
471
    }
472
473
    /**
474
    * Save the state of the caching memory array into a cache file cache
475
    *
476
    * @param string $id cache id
477
    * @param string $group name of the cache group
478
    * @access public
479
    */
480
    function saveMemoryCachingState($id, $group = 'default')
481
    {
482
        if ($this->_caching) {
483
            $array = array(
484
                'counter' => $this->_memoryCachingCounter,
485
                'array' => $this->_memoryCachingState
486
            );
487
            $data = serialize($array);
488
            $this->save($data, $id, $group);
489
        }
490
    }
491
492
    /**
493
    * Load the state of the caching memory array from a given cache file cache
494
    *
495
    * @param string $id cache id
496
    * @param string $group name of the cache group
497
    * @param boolean $doNotTestCacheValidity if set to true, the cache validity won't be tested
498
    * @access public
499
    */
500
    function getMemoryCachingState($id, $group = 'default', $doNotTestCacheValidity = false)
501
    {
502
        if ($this->_caching) {
503
            if ($data = $this->get($id, $group, $doNotTestCacheValidity)) {
504
                $array = unserialize($data);
505
                $this->_memoryCachingCounter = $array['counter'];
506
                $this->_memoryCachingArray = $array['array'];
507
            }
508
        }
509
    }
510
511
    /**
512
    * Return the cache last modification time
513
    *
514
    * BE CAREFUL : THIS METHOD IS FOR HACKING ONLY !
515
    *
516
    * @return int last modification time
517
    */
518
    function lastModified()
519
    {
520
        return @filemtime($this->_file);
521
    }
522
523
    /**
524
    * Trigger error
525
    *
526
    * @param string $msg error message
527
    * @param int $code error code
528
    * @access public
529
    */
530
    function raiseError($msg, $code)
531
    {
532
        return new Exception($msg);
533
    }
534
535
    /**
536
     * Extend the life of a valid cache file
537
     *
538
     * see http://pear.php.net/bugs/bug.php?id=6681
539
     *
540
     * @access public
541
     */
542
    function extendLife()
543
    {
544
        @touch($this->_file);
545
    }
546
547
    // --- Private methods ---
548
549
    /**
550
    * Compute & set the refresh time
551
    *
552
    * @access private
553
    */
554
    function _setRefreshTime()
555
    {
556
        if (is_null($this->_lifeTime)) {
557
            $this->_refreshTime = null;
558
        } else {
559
            $this->_refreshTime = time() - $this->_lifeTime;
560
        }
561
    }
562
563
    /**
564
    * Remove a file
565
    *
566
    * @param string $file complete file path and name
567
    * @return boolean true if no problem
568
    * @access private
569
    */
570
    function _unlink($file)
571
    {
572
        if (!@unlink($file)) {
573
            return $this->raiseError('Cache_Lite : Unable to remove cache !', -3);
574
        }
575
        return true;
576
    }
577
578
    /**
579
    * Recursive function for cleaning cache file in the given directory
580
    *
581
    * @param string $dir directory complete path (with a trailing slash)
582
    * @param string $group name of the cache group
583
    * @param string $mode flush cache mode : 'old', 'ingroup', 'notingroup',
584
                                             'callback_myFunction'
585
    * @return boolean true if no problem
586
    * @access private
587
    */
588
    function _cleanDir($dir, $group = false, $mode = 'ingroup')
589
    {
590
        if ($this->_fileNameProtection) {
591
            $motif = ($group) ? 'cache_'.md5($group).'_' : 'cache_';
592
        } else {
593
            $motif = ($group) ? 'cache_'.$group.'_' : 'cache_';
594
        }
595
        if ($this->_memoryCaching) {
596
            while (list($key, ) = each($this->_memoryCachingArray)) {
597
                if (strpos($key, $motif, 0)) {
598
                    unset($this->_memoryCachingArray[$key]);
599
                    $this->_memoryCachingCounter = $this->_memoryCachingCounter - 1;
600
                }
601
            }
602
            if ($this->_onlyMemoryCaching) {
603
                return true;
604
            }
605
        }
606
        if (!($dh = opendir($dir))) {
607
            return $this->raiseError('Cache_Lite : Unable to open cache directory !', -4);
608
        }
609
        $result = true;
610
        while ($file = readdir($dh)) {
611
            if (($file != '.') && ($file != '..')) {
612
                if (substr($file, 0, 6)=='cache_') {
613
                    $file2 = $dir . $file;
614
                    if (is_file($file2)) {
615
                        switch (substr($mode, 0, 9)) {
616
                            case 'old':
617
                                // files older than lifeTime get deleted from cache
618
                                if (!is_null($this->_lifeTime)) {
619
                                    if ((time() - @filemtime($file2)) > $this->_lifeTime) {
620
                                        $result = ($result and ($this->_unlink($file2)));
621
                                    }
622
                                }
623
                                break;
624
                            case 'notingroup':
625
                                if (!strpos($file2, $motif, 0)) {
626
                                    $result = ($result and ($this->_unlink($file2)));
627
                                }
628
                                break;
629
                            case 'callback_':
630
                                $func = substr($mode, 9, strlen($mode) - 9);
631
                                if ($func($file2, $group)) {
632
                                    $result = ($result and ($this->_unlink($file2)));
633
                                }
634
                                break;
635
                            case 'ingroup':
636
                            default:
637
                                if (strpos($file2, $motif, 0)) {
638
                                    $result = ($result and ($this->_unlink($file2)));
639
                                }
640
                                break;
641
                        }
642
                    }
643
                    if ((is_dir($file2)) and ($this->_hashedDirectoryLevel>0)) {
644
                        $result = ($result and ($this->_cleanDir($file2 . '/', $group, $mode)));
645
                    }
646
                }
647
            }
648
        }
649
        return $result;
650
    }
651
652
    /**
653
    * Add some date in the memory caching array
654
    *
655
    * @param string $data data to cache
656
    * @access private
657
    */
658
    function _memoryCacheAdd($data)
659
    {
660
        $this->_memoryCachingArray[$this->_file] = $data;
661
        if ($this->_memoryCachingCounter >= $this->_memoryCachingLimit) {
662
            list($key, ) = each($this->_memoryCachingArray);
663
            unset($this->_memoryCachingArray[$key]);
664
        } else {
665
            $this->_memoryCachingCounter = $this->_memoryCachingCounter + 1;
666
        }
667
    }
668
669
    /**
670
    * Make a file name (with path)
671
    *
672
    * @param string $id cache id
673
    * @param string $group name of the group
674
    * @access private
675
    */
676
    function _setFileName($id, $group)
677
    {
678
        if ($this->_fileNameProtection) {
679
            $suffix = 'cache_'.md5($group).'_'.md5($id);
680
        } else {
681
            $suffix = 'cache_'.$group.'_'.$id;
682
        }
683
        $root = $this->_cacheDir;
684
        if ($this->_hashedDirectoryLevel>0) {
685
            $hash = md5($suffix);
686
            for ($i=0 ; $i<$this->_hashedDirectoryLevel ; $i++) {
687
                $root = $root . 'cache_' . substr($hash, 0, $i + 1) . '/';
688
            }
689
        }
690
        $this->_fileName = $suffix;
691
        $this->_file = $root.$suffix;
692
    }
693
694
    /**
695
    * Read the cache file and return the content
696
    *
697
    * @return string content of the cache file (else : false or a PEAR_Error object)
698
    * @access private
699
    */
700
    function _read()
701
    {
702
        $fp = @fopen($this->_file, "rb");
703
        if ($this->_fileLocking) @flock($fp, LOCK_SH);
704
        if ($fp) {
705
            clearstatcache();
706
            $length = @filesize($this->_file);
707
            // $mqr = get_magic_quotes_runtime();
708
            // set_magic_quotes_runtime(0);
709
            if ($this->_readControl) {
710
                $hashControl = @fread($fp, 32);
711
                $length = $length - 32;
712
            }
713
            if ($length) {
714
                $data = @fread($fp, $length);
715
            } else {
716
                $data = '';
717
            }
718
            // set_magic_quotes_runtime($mqr);
719
            if ($this->_fileLocking) @flock($fp, LOCK_UN);
720
            @fclose($fp);
721
            if ($this->_readControl) {
722
                $hashData = $this->_hash($data, $this->_readControlType);
723
                if ($hashData != $hashControl) {
724
                    if (!(is_null($this->_lifeTime))) {
725
                        @touch($this->_file, time() - 2*abs($this->_lifeTime));
726
                    } else {
727
                        @unlink($this->_file);
728
                    }
729
                    return false;
730
                }
731
            }
732
            return $data;
733
        }
734
        return $this->raiseError('Cache_Lite : Unable to read cache !', -2);
735
    }
736
737
    /**
738
    * Write the given data in the cache file
739
    *
740
    * @param string $data data to put in cache
741
    * @return boolean true if ok (a PEAR_Error object else)
742
    * @access private
743
    */
744
    function _write($data)
745
    {
746
        $oldmask = umask(0);
747
    	if ($this->_hashedDirectoryLevel > 0) {
748
            $hash = md5($this->_fileName);
749
            $root = $this->_cacheDir;
750
            for ($i=0 ; $i<$this->_hashedDirectoryLevel ; $i++) {
751
                $root = $root . 'cache_' . substr($hash, 0, $i + 1) . '/';
752
                if (!(@is_dir($root))) {
753
                    @mkdir($root, $this->_hashedDirectoryUmask);
754
                }
755
            }
756
        }
757
        $fp = @fopen($this->_file, "wb");
758
        if ($fp) {
759
            if ($this->_fileLocking) @flock($fp, LOCK_EX);
760
            if ($this->_readControl) {
761
                @fwrite($fp, $this->_hash($data, $this->_readControlType), 32);
762
            }
763
            $len = strlen($data);
764
            @fwrite($fp, $data, $len);
765
            if ($this->_fileLocking) @flock($fp, LOCK_UN);
766
            @fclose($fp);
767
            umask($oldmask);
768
            return true;
769
        }
770
        umask($oldmask);
771
        return $this->raiseError('Cache_Lite : Unable to write cache file : '.$this->_file, -1);
772
    }
773
774
    /**
775
    * Write the given data in the cache file and control it just after to avoir corrupted cache entries
776
    *
777
    * @param string $data data to put in cache
778
    * @return boolean true if the test is ok (else : false or a PEAR_Error object)
779
    * @access private
780
    */
781
    function _writeAndControl($data)
782
    {
783
        $result = $this->_write($data);
784
        if (is_object($result)) {
785
            return $result; # We return the PEAR_Error object
786
        }
787
        $dataRead = $this->_read();
788
        if (is_object($dataRead)) {
789
            return $result; # We return the PEAR_Error object
790
        }
791
        if ((is_bool($dataRead)) && (!$dataRead)) {
792
            return false;
793
        }
794
        return ($dataRead==$data);
795
    }
796
797
    /**
798
    * Make a control key with the string containing datas
799
    *
800
    * @param string $data data
801
    * @param string $controlType type of control 'md5', 'crc32' or 'strlen'
802
    * @return string control key
803
    * @access private
804
    */
805
    function _hash($data, $controlType)
806
    {
807
        switch ($controlType) {
808
        case 'md5':
809
            return md5($data);
810
        case 'crc32':
811
            return sprintf('% 32d', crc32($data));
812
        case 'strlen':
813
            return sprintf('% 32d', strlen($data));
814
        default:
815
            return $this->raiseError('Unknown controlType ! (available values are only \'md5\', \'crc32\', \'strlen\')', -5);
816
        }
817
    }
818
819
}
820
821
?>
822