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root / drupal7 / includes / bootstrap.inc @ 01f36513

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<?php
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3
/**
4
 * @file
5
 * Functions that need to be loaded on every Drupal request.
6
 */
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8
/**
9
 * The current system version.
10
 */
11
define('VERSION', '7.59');
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/**
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 * Core API compatibility.
15
 */
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define('DRUPAL_CORE_COMPATIBILITY', '7.x');
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/**
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 * Minimum supported version of PHP.
20
 */
21
define('DRUPAL_MINIMUM_PHP', '5.2.4');
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23
/**
24
 * Minimum recommended value of PHP memory_limit.
25
 */
26
define('DRUPAL_MINIMUM_PHP_MEMORY_LIMIT', '32M');
27

    
28
/**
29
 * Error reporting level: display no errors.
30
 */
31
define('ERROR_REPORTING_HIDE', 0);
32

    
33
/**
34
 * Error reporting level: display errors and warnings.
35
 */
36
define('ERROR_REPORTING_DISPLAY_SOME', 1);
37

    
38
/**
39
 * Error reporting level: display all messages.
40
 */
41
define('ERROR_REPORTING_DISPLAY_ALL', 2);
42

    
43
/**
44
 * Indicates that the item should never be removed unless explicitly selected.
45
 *
46
 * The item may be removed using cache_clear_all() with a cache ID.
47
 */
48
define('CACHE_PERMANENT', 0);
49

    
50
/**
51
 * Indicates that the item should be removed at the next general cache wipe.
52
 */
53
define('CACHE_TEMPORARY', -1);
54

    
55
/**
56
 * @defgroup logging_severity_levels Logging severity levels
57
 * @{
58
 * Logging severity levels as defined in RFC 3164.
59
 *
60
 * The WATCHDOG_* constant definitions correspond to the logging severity levels
61
 * defined in RFC 3164, section 4.1.1. PHP supplies predefined LOG_* constants
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 * for use in the syslog() function, but their values on Windows builds do not
63
 * correspond to RFC 3164. The associated PHP bug report was closed with the
64
 * comment, "And it's also not a bug, as Windows just have less log levels,"
65
 * and "So the behavior you're seeing is perfectly normal."
66
 *
67
 * @see http://www.faqs.org/rfcs/rfc3164.html
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 * @see http://bugs.php.net/bug.php?id=18090
69
 * @see http://php.net/manual/function.syslog.php
70
 * @see http://php.net/manual/network.constants.php
71
 * @see watchdog()
72
 * @see watchdog_severity_levels()
73
 */
74

    
75
/**
76
 * Log message severity -- Emergency: system is unusable.
77
 */
78
define('WATCHDOG_EMERGENCY', 0);
79

    
80
/**
81
 * Log message severity -- Alert: action must be taken immediately.
82
 */
83
define('WATCHDOG_ALERT', 1);
84

    
85
/**
86
 * Log message severity -- Critical conditions.
87
 */
88
define('WATCHDOG_CRITICAL', 2);
89

    
90
/**
91
 * Log message severity -- Error conditions.
92
 */
93
define('WATCHDOG_ERROR', 3);
94

    
95
/**
96
 * Log message severity -- Warning conditions.
97
 */
98
define('WATCHDOG_WARNING', 4);
99

    
100
/**
101
 * Log message severity -- Normal but significant conditions.
102
 */
103
define('WATCHDOG_NOTICE', 5);
104

    
105
/**
106
 * Log message severity -- Informational messages.
107
 */
108
define('WATCHDOG_INFO', 6);
109

    
110
/**
111
 * Log message severity -- Debug-level messages.
112
 */
113
define('WATCHDOG_DEBUG', 7);
114

    
115
/**
116
 * @} End of "defgroup logging_severity_levels".
117
 */
118

    
119
/**
120
 * First bootstrap phase: initialize configuration.
121
 */
122
define('DRUPAL_BOOTSTRAP_CONFIGURATION', 0);
123

    
124
/**
125
 * Second bootstrap phase: try to serve a cached page.
126
 */
127
define('DRUPAL_BOOTSTRAP_PAGE_CACHE', 1);
128

    
129
/**
130
 * Third bootstrap phase: initialize database layer.
131
 */
132
define('DRUPAL_BOOTSTRAP_DATABASE', 2);
133

    
134
/**
135
 * Fourth bootstrap phase: initialize the variable system.
136
 */
137
define('DRUPAL_BOOTSTRAP_VARIABLES', 3);
138

    
139
/**
140
 * Fifth bootstrap phase: initialize session handling.
141
 */
142
define('DRUPAL_BOOTSTRAP_SESSION', 4);
143

    
144
/**
145
 * Sixth bootstrap phase: set up the page header.
146
 */
147
define('DRUPAL_BOOTSTRAP_PAGE_HEADER', 5);
148

    
149
/**
150
 * Seventh bootstrap phase: find out language of the page.
151
 */
152
define('DRUPAL_BOOTSTRAP_LANGUAGE', 6);
153

    
154
/**
155
 * Final bootstrap phase: Drupal is fully loaded; validate and fix input data.
156
 */
157
define('DRUPAL_BOOTSTRAP_FULL', 7);
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159
/**
160
 * Role ID for anonymous users; should match what's in the "role" table.
161
 */
162
define('DRUPAL_ANONYMOUS_RID', 1);
163

    
164
/**
165
 * Role ID for authenticated users; should match what's in the "role" table.
166
 */
167
define('DRUPAL_AUTHENTICATED_RID', 2);
168

    
169
/**
170
 * The number of bytes in a kilobyte.
171
 *
172
 * For more information, visit http://en.wikipedia.org/wiki/Kilobyte.
173
 */
174
define('DRUPAL_KILOBYTE', 1024);
175

    
176
/**
177
 * The language code used when no language is explicitly assigned.
178
 *
179
 * Defined by ISO639-2 for "Undetermined".
180
 */
181
define('LANGUAGE_NONE', 'und');
182

    
183
/**
184
 * The type of language used to define the content language.
185
 */
186
define('LANGUAGE_TYPE_CONTENT', 'language_content');
187

    
188
/**
189
 * The type of language used to select the user interface.
190
 */
191
define('LANGUAGE_TYPE_INTERFACE', 'language');
192

    
193
/**
194
 * The type of language used for URLs.
195
 */
196
define('LANGUAGE_TYPE_URL', 'language_url');
197

    
198
/**
199
 * Language written left to right. Possible value of $language->direction.
200
 */
201
define('LANGUAGE_LTR', 0);
202

    
203
/**
204
 * Language written right to left. Possible value of $language->direction.
205
 */
206
define('LANGUAGE_RTL', 1);
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208
/**
209
 * Time of the current request in seconds elapsed since the Unix Epoch.
210
 *
211
 * This differs from $_SERVER['REQUEST_TIME'], which is stored as a float
212
 * since PHP 5.4.0. Float timestamps confuse most PHP functions
213
 * (including date_create()).
214
 *
215
 * @see http://php.net/manual/reserved.variables.server.php
216
 * @see http://php.net/manual/function.time.php
217
 */
218
define('REQUEST_TIME', (int) $_SERVER['REQUEST_TIME']);
219

    
220
/**
221
 * Flag used to indicate that text is not sanitized, so run check_plain().
222
 *
223
 * @see drupal_set_title()
224
 */
225
define('CHECK_PLAIN', 0);
226

    
227
/**
228
 * Flag used to indicate that text has already been sanitized.
229
 *
230
 * @see drupal_set_title()
231
 */
232
define('PASS_THROUGH', -1);
233

    
234
/**
235
 * Signals that the registry lookup cache should be reset.
236
 */
237
define('REGISTRY_RESET_LOOKUP_CACHE', 1);
238

    
239
/**
240
 * Signals that the registry lookup cache should be written to storage.
241
 */
242
define('REGISTRY_WRITE_LOOKUP_CACHE', 2);
243

    
244
/**
245
 * Regular expression to match PHP function names.
246
 *
247
 * @see http://php.net/manual/language.functions.php
248
 */
249
define('DRUPAL_PHP_FUNCTION_PATTERN', '[a-zA-Z_\x7f-\xff][a-zA-Z0-9_\x7f-\xff]*');
250

    
251
/**
252
 * A RFC7231 Compliant date.
253
 *
254
 * http://tools.ietf.org/html/rfc7231#section-7.1.1.1
255
 *
256
 * Example: Sun, 06 Nov 1994 08:49:37 GMT
257
 *
258
 * This constant was introduced in PHP 7.0.19 and PHP 7.1.5 but needs to be
259
 * defined by Drupal for earlier PHP versions.
260
 */
261
if (!defined('DATE_RFC7231')) {
262
  define('DATE_RFC7231', 'D, d M Y H:i:s \G\M\T');
263
}
264

    
265
/**
266
 * Provides a caching wrapper to be used in place of large array structures.
267
 *
268
 * This class should be extended by systems that need to cache large amounts
269
 * of data and have it represented as an array to calling functions. These
270
 * arrays can become very large, so ArrayAccess is used to allow different
271
 * strategies to be used for caching internally (lazy loading, building caches
272
 * over time etc.). This can dramatically reduce the amount of data that needs
273
 * to be loaded from cache backends on each request, and memory usage from
274
 * static caches of that same data.
275
 *
276
 * Note that array_* functions do not work with ArrayAccess. Systems using
277
 * DrupalCacheArray should use this only internally. If providing API functions
278
 * that return the full array, this can be cached separately or returned
279
 * directly. However since DrupalCacheArray holds partial content by design, it
280
 * should be a normal PHP array or otherwise contain the full structure.
281
 *
282
 * Note also that due to limitations in PHP prior to 5.3.4, it is impossible to
283
 * write directly to the contents of nested arrays contained in this object.
284
 * Only writes to the top-level array elements are possible. So if you
285
 * previously had set $object['foo'] = array(1, 2, 'bar' => 'baz'), but later
286
 * want to change the value of 'bar' from 'baz' to 'foobar', you cannot do so
287
 * a targeted write like $object['foo']['bar'] = 'foobar'. Instead, you must
288
 * overwrite the entire top-level 'foo' array with the entire set of new
289
 * values: $object['foo'] = array(1, 2, 'bar' => 'foobar'). Due to this same
290
 * limitation, attempts to create references to any contained data, nested or
291
 * otherwise, will fail silently. So $var = &$object['foo'] will not throw an
292
 * error, and $var will be populated with the contents of $object['foo'], but
293
 * that data will be passed by value, not reference. For more information on
294
 * the PHP limitation, see the note in the official PHP documentation at·
295
 * http://php.net/manual/arrayaccess.offsetget.php on
296
 * ArrayAccess::offsetGet().
297
 *
298
 * By default, the class accounts for caches where calling functions might
299
 * request keys in the array that won't exist even after a cache rebuild. This
300
 * prevents situations where a cache rebuild would be triggered over and over
301
 * due to a 'missing' item. These cases are stored internally as a value of
302
 * NULL. This means that the offsetGet() and offsetExists() methods
303
 * must be overridden if caching an array where the top level values can
304
 * legitimately be NULL, and where $object->offsetExists() needs to correctly
305
 * return (equivalent to array_key_exists() vs. isset()). This should not
306
 * be necessary in the majority of cases.
307
 *
308
 * Classes extending this class must override at least the
309
 * resolveCacheMiss() method to have a working implementation.
310
 *
311
 * offsetSet() is not overridden by this class by default. In practice this
312
 * means that assigning an offset via arrayAccess will only apply while the
313
 * object is in scope and will not be written back to the persistent cache.
314
 * This follows a similar pattern to static vs. persistent caching in
315
 * procedural code. Extending classes may wish to alter this behavior, for
316
 * example by overriding offsetSet() and adding an automatic call to persist().
317
 *
318
 * @see SchemaCache
319
 */
320
abstract class DrupalCacheArray implements ArrayAccess {
321

    
322
  /**
323
   * A cid to pass to cache_set() and cache_get().
324
   */
325
  protected $cid;
326

    
327
  /**
328
   * A bin to pass to cache_set() and cache_get().
329
   */
330
  protected $bin;
331

    
332
  /**
333
   * An array of keys to add to the cache at the end of the request.
334
   */
335
  protected $keysToPersist = array();
336

    
337
  /**
338
   * Storage for the data itself.
339
   */
340
  protected $storage = array();
341

    
342
  /**
343
   * Constructs a DrupalCacheArray object.
344
   *
345
   * @param $cid
346
   *   The cid for the array being cached.
347
   * @param $bin
348
   *   The bin to cache the array.
349
   */
350
  public function __construct($cid, $bin) {
351
    $this->cid = $cid;
352
    $this->bin = $bin;
353

    
354
    if ($cached = cache_get($this->cid, $this->bin)) {
355
     $this->storage = $cached->data;
356
    }
357
  }
358

    
359
  /**
360
   * Implements ArrayAccess::offsetExists().
361
   */
362
  public function offsetExists($offset) {
363
    return $this->offsetGet($offset) !== NULL;
364
  }
365

    
366
  /**
367
   * Implements ArrayAccess::offsetGet().
368
   */
369
  public function offsetGet($offset) {
370
    if (isset($this->storage[$offset]) || array_key_exists($offset, $this->storage)) {
371
      return $this->storage[$offset];
372
    }
373
    else {
374
      return $this->resolveCacheMiss($offset);
375
    }
376
  }
377

    
378
  /**
379
   * Implements ArrayAccess::offsetSet().
380
   */
381
  public function offsetSet($offset, $value) {
382
    $this->storage[$offset] = $value;
383
  }
384

    
385
  /**
386
   * Implements ArrayAccess::offsetUnset().
387
   */
388
  public function offsetUnset($offset) {
389
    unset($this->storage[$offset]);
390
  }
391

    
392
  /**
393
   * Flags an offset value to be written to the persistent cache.
394
   *
395
   * If a value is assigned to a cache object with offsetSet(), by default it
396
   * will not be written to the persistent cache unless it is flagged with this
397
   * method. This allows items to be cached for the duration of a request,
398
   * without necessarily writing back to the persistent cache at the end.
399
   *
400
   * @param $offset
401
   *   The array offset that was requested.
402
   * @param $persist
403
   *   Optional boolean to specify whether the offset should be persisted or
404
   *   not, defaults to TRUE. When called with $persist = FALSE the offset will
405
   *   be unflagged so that it will not be written at the end of the request.
406
   */
407
  protected function persist($offset, $persist = TRUE) {
408
    $this->keysToPersist[$offset] = $persist;
409
  }
410

    
411
  /**
412
   * Resolves a cache miss.
413
   *
414
   * When an offset is not found in the object, this is treated as a cache
415
   * miss. This method allows classes implementing the interface to look up
416
   * the actual value and allow it to be cached.
417
   *
418
   * @param $offset
419
   *   The offset that was requested.
420
   *
421
   * @return
422
   *   The value of the offset, or NULL if no value was found.
423
   */
424
  abstract protected function resolveCacheMiss($offset);
425

    
426
  /**
427
   * Writes a value to the persistent cache immediately.
428
   *
429
   * @param $data
430
   *   The data to write to the persistent cache.
431
   * @param $lock
432
   *   Whether to acquire a lock before writing to cache.
433
   */
434
  protected function set($data, $lock = TRUE) {
435
    // Lock cache writes to help avoid stampedes.
436
    // To implement locking for cache misses, override __construct().
437
    $lock_name = $this->cid . ':' . $this->bin;
438
    if (!$lock || lock_acquire($lock_name)) {
439
      if ($cached = cache_get($this->cid, $this->bin)) {
440
        $data = $cached->data + $data;
441
      }
442
      cache_set($this->cid, $data, $this->bin);
443
      if ($lock) {
444
        lock_release($lock_name);
445
      }
446
    }
447
  }
448

    
449
  /**
450
   * Destructs the DrupalCacheArray object.
451
   */
452
  public function __destruct() {
453
    $data = array();
454
    foreach ($this->keysToPersist as $offset => $persist) {
455
      if ($persist) {
456
        $data[$offset] = $this->storage[$offset];
457
      }
458
    }
459
    if (!empty($data)) {
460
      $this->set($data);
461
    }
462
  }
463
}
464

    
465
/**
466
 * Starts the timer with the specified name.
467
 *
468
 * If you start and stop the same timer multiple times, the measured intervals
469
 * will be accumulated.
470
 *
471
 * @param $name
472
 *   The name of the timer.
473
 */
474
function timer_start($name) {
475
  global $timers;
476

    
477
  $timers[$name]['start'] = microtime(TRUE);
478
  $timers[$name]['count'] = isset($timers[$name]['count']) ? ++$timers[$name]['count'] : 1;
479
}
480

    
481
/**
482
 * Reads the current timer value without stopping the timer.
483
 *
484
 * @param $name
485
 *   The name of the timer.
486
 *
487
 * @return
488
 *   The current timer value in ms.
489
 */
490
function timer_read($name) {
491
  global $timers;
492

    
493
  if (isset($timers[$name]['start'])) {
494
    $stop = microtime(TRUE);
495
    $diff = round(($stop - $timers[$name]['start']) * 1000, 2);
496

    
497
    if (isset($timers[$name]['time'])) {
498
      $diff += $timers[$name]['time'];
499
    }
500
    return $diff;
501
  }
502
  return $timers[$name]['time'];
503
}
504

    
505
/**
506
 * Stops the timer with the specified name.
507
 *
508
 * @param $name
509
 *   The name of the timer.
510
 *
511
 * @return
512
 *   A timer array. The array contains the number of times the timer has been
513
 *   started and stopped (count) and the accumulated timer value in ms (time).
514
 */
515
function timer_stop($name) {
516
  global $timers;
517

    
518
  if (isset($timers[$name]['start'])) {
519
    $stop = microtime(TRUE);
520
    $diff = round(($stop - $timers[$name]['start']) * 1000, 2);
521
    if (isset($timers[$name]['time'])) {
522
      $timers[$name]['time'] += $diff;
523
    }
524
    else {
525
      $timers[$name]['time'] = $diff;
526
    }
527
    unset($timers[$name]['start']);
528
  }
529

    
530
  return $timers[$name];
531
}
532

    
533
/**
534
 * Returns the appropriate configuration directory.
535
 *
536
 * Returns the configuration path based on the site's hostname, port, and
537
 * pathname. See default.settings.php for examples on how the URL is converted
538
 * to a directory.
539
 *
540
 * @param bool $require_settings
541
 *   Only configuration directories with an existing settings.php file
542
 *   will be recognized. Defaults to TRUE. During initial installation,
543
 *   this is set to FALSE so that Drupal can detect a matching directory,
544
 *   then create a new settings.php file in it.
545
 * @param bool $reset
546
 *   Force a full search for matching directories even if one had been
547
 *   found previously. Defaults to FALSE.
548
 *
549
 * @return
550
 *   The path of the matching directory.
551
 *
552
 * @see default.settings.php
553
 */
554
function conf_path($require_settings = TRUE, $reset = FALSE) {
555
  $conf = &drupal_static(__FUNCTION__, '');
556

    
557
  if ($conf && !$reset) {
558
    return $conf;
559
  }
560

    
561
  $confdir = 'sites';
562

    
563
  $sites = array();
564
  if (file_exists(DRUPAL_ROOT . '/' . $confdir . '/sites.php')) {
565
    // This will overwrite $sites with the desired mappings.
566
    include(DRUPAL_ROOT . '/' . $confdir . '/sites.php');
567
  }
568

    
569
  $uri = explode('/', $_SERVER['SCRIPT_NAME'] ? $_SERVER['SCRIPT_NAME'] : $_SERVER['SCRIPT_FILENAME']);
570
  $server = explode('.', implode('.', array_reverse(explode(':', rtrim($_SERVER['HTTP_HOST'], '.')))));
571
  for ($i = count($uri) - 1; $i > 0; $i--) {
572
    for ($j = count($server); $j > 0; $j--) {
573
      $dir = implode('.', array_slice($server, -$j)) . implode('.', array_slice($uri, 0, $i));
574
      if (isset($sites[$dir]) && file_exists(DRUPAL_ROOT . '/' . $confdir . '/' . $sites[$dir])) {
575
        $dir = $sites[$dir];
576
      }
577
      if (file_exists(DRUPAL_ROOT . '/' . $confdir . '/' . $dir . '/settings.php') || (!$require_settings && file_exists(DRUPAL_ROOT . '/' . $confdir . '/' . $dir))) {
578
        $conf = "$confdir/$dir";
579
        return $conf;
580
      }
581
    }
582
  }
583
  $conf = "$confdir/default";
584
  return $conf;
585
}
586

    
587
/**
588
 * Sets appropriate server variables needed for command line scripts to work.
589
 *
590
 * This function can be called by command line scripts before bootstrapping
591
 * Drupal, to ensure that the page loads with the desired server parameters.
592
 * This is because many parts of Drupal assume that they are running in a web
593
 * browser and therefore use information from the global PHP $_SERVER variable
594
 * that does not get set when Drupal is run from the command line.
595
 *
596
 * In many cases, the default way in which this function populates the $_SERVER
597
 * variable is sufficient, and it can therefore be called without passing in
598
 * any input. However, command line scripts running on a multisite installation
599
 * (or on any installation that has settings.php stored somewhere other than
600
 * the sites/default folder) need to pass in the URL of the site to allow
601
 * Drupal to detect the correct location of the settings.php file. Passing in
602
 * the 'url' parameter is also required for functions like request_uri() to
603
 * return the expected values.
604
 *
605
 * Most other parameters do not need to be passed in, but may be necessary in
606
 * some cases; for example, if Drupal's ip_address() function needs to return
607
 * anything but the standard localhost value ('127.0.0.1'), the command line
608
 * script should pass in the desired value via the 'REMOTE_ADDR' key.
609
 *
610
 * @param $variables
611
 *   (optional) An associative array of variables within $_SERVER that should
612
 *   be replaced. If the special element 'url' is provided in this array, it
613
 *   will be used to populate some of the server defaults; it should be set to
614
 *   the URL of the current page request, excluding any $_GET request but
615
 *   including the script name (e.g., http://www.example.com/mysite/index.php).
616
 *
617
 * @see conf_path()
618
 * @see request_uri()
619
 * @see ip_address()
620
 */
621
function drupal_override_server_variables($variables = array()) {
622
  // Allow the provided URL to override any existing values in $_SERVER.
623
  if (isset($variables['url'])) {
624
    $url = parse_url($variables['url']);
625
    if (isset($url['host'])) {
626
      $_SERVER['HTTP_HOST'] = $url['host'];
627
    }
628
    if (isset($url['path'])) {
629
      $_SERVER['SCRIPT_NAME'] = $url['path'];
630
    }
631
    unset($variables['url']);
632
  }
633
  // Define default values for $_SERVER keys. These will be used if $_SERVER
634
  // does not already define them and no other values are passed in to this
635
  // function.
636
  $defaults = array(
637
    'HTTP_HOST' => 'localhost',
638
    'SCRIPT_NAME' => NULL,
639
    'REMOTE_ADDR' => '127.0.0.1',
640
    'REQUEST_METHOD' => 'GET',
641
    'SERVER_NAME' => NULL,
642
    'SERVER_SOFTWARE' => NULL,
643
    'HTTP_USER_AGENT' => NULL,
644
  );
645
  // Replace elements of the $_SERVER array, as appropriate.
646
  $_SERVER = $variables + $_SERVER + $defaults;
647
}
648

    
649
/**
650
 * Initializes the PHP environment.
651
 */
652
function drupal_environment_initialize() {
653
  if (!isset($_SERVER['HTTP_REFERER'])) {
654
    $_SERVER['HTTP_REFERER'] = '';
655
  }
656
  if (!isset($_SERVER['SERVER_PROTOCOL']) || ($_SERVER['SERVER_PROTOCOL'] != 'HTTP/1.0' && $_SERVER['SERVER_PROTOCOL'] != 'HTTP/1.1')) {
657
    $_SERVER['SERVER_PROTOCOL'] = 'HTTP/1.0';
658
  }
659

    
660
  if (isset($_SERVER['HTTP_HOST'])) {
661
    // As HTTP_HOST is user input, ensure it only contains characters allowed
662
    // in hostnames. See RFC 952 (and RFC 2181).
663
    // $_SERVER['HTTP_HOST'] is lowercased here per specifications.
664
    $_SERVER['HTTP_HOST'] = strtolower($_SERVER['HTTP_HOST']);
665
    if (!drupal_valid_http_host($_SERVER['HTTP_HOST'])) {
666
      // HTTP_HOST is invalid, e.g. if containing slashes it may be an attack.
667
      header($_SERVER['SERVER_PROTOCOL'] . ' 400 Bad Request');
668
      exit;
669
    }
670
  }
671
  else {
672
    // Some pre-HTTP/1.1 clients will not send a Host header. Ensure the key is
673
    // defined for E_ALL compliance.
674
    $_SERVER['HTTP_HOST'] = '';
675
  }
676

    
677
  // When clean URLs are enabled, emulate ?q=foo/bar using REQUEST_URI. It is
678
  // not possible to append the query string using mod_rewrite without the B
679
  // flag (this was added in Apache 2.2.8), because mod_rewrite unescapes the
680
  // path before passing it on to PHP. This is a problem when the path contains
681
  // e.g. "&" or "%" that have special meanings in URLs and must be encoded.
682
  $_GET['q'] = request_path();
683

    
684
  // Enforce E_ALL, but allow users to set levels not part of E_ALL.
685
  error_reporting(E_ALL | error_reporting());
686

    
687
  // Override PHP settings required for Drupal to work properly.
688
  // sites/default/default.settings.php contains more runtime settings.
689
  // The .htaccess file contains settings that cannot be changed at runtime.
690

    
691
  // Don't escape quotes when reading files from the database, disk, etc.
692
  ini_set('magic_quotes_runtime', '0');
693
  // Use session cookies, not transparent sessions that puts the session id in
694
  // the query string.
695
  ini_set('session.use_cookies', '1');
696
  ini_set('session.use_only_cookies', '1');
697
  ini_set('session.use_trans_sid', '0');
698
  // Don't send HTTP headers using PHP's session handler.
699
  // An empty string is used here to disable the cache limiter.
700
  ini_set('session.cache_limiter', '');
701
  // Use httponly session cookies.
702
  ini_set('session.cookie_httponly', '1');
703

    
704
  // Set sane locale settings, to ensure consistent string, dates, times and
705
  // numbers handling.
706
  setlocale(LC_ALL, 'C');
707
}
708

    
709
/**
710
 * Validates that a hostname (for example $_SERVER['HTTP_HOST']) is safe.
711
 *
712
 * @return
713
 *  TRUE if only containing valid characters, or FALSE otherwise.
714
 */
715
function drupal_valid_http_host($host) {
716
  // Limit the length of the host name to 1000 bytes to prevent DoS attacks with
717
  // long host names.
718
  return strlen($host) <= 1000
719
    // Limit the number of subdomains and port separators to prevent DoS attacks
720
    // in conf_path().
721
    && substr_count($host, '.') <= 100
722
    && substr_count($host, ':') <= 100
723
    && preg_match('/^\[?(?:[a-zA-Z0-9-:\]_]+\.?)+$/', $host);
724
}
725

    
726
/**
727
 * Checks whether an HTTPS request is being served.
728
 *
729
 * @return bool
730
 *   TRUE if the request is HTTPS, FALSE otherwise.
731
 */
732
function drupal_is_https() {
733
  return isset($_SERVER['HTTPS']) && strtolower($_SERVER['HTTPS']) == 'on';
734
}
735

    
736
/**
737
 * Sets the base URL, cookie domain, and session name from configuration.
738
 */
739
function drupal_settings_initialize() {
740
  global $base_url, $base_path, $base_root;
741

    
742
  // Export these settings.php variables to the global namespace.
743
  global $databases, $cookie_domain, $conf, $installed_profile, $update_free_access, $db_url, $db_prefix, $drupal_hash_salt, $is_https, $base_secure_url, $base_insecure_url;
744
  $conf = array();
745

    
746
  if (file_exists(DRUPAL_ROOT . '/' . conf_path() . '/settings.php')) {
747
    include_once DRUPAL_ROOT . '/' . conf_path() . '/settings.php';
748
  }
749
  $is_https = drupal_is_https();
750

    
751
  if (isset($base_url)) {
752
    // Parse fixed base URL from settings.php.
753
    $parts = parse_url($base_url);
754
    if (!isset($parts['path'])) {
755
      $parts['path'] = '';
756
    }
757
    $base_path = $parts['path'] . '/';
758
    // Build $base_root (everything until first slash after "scheme://").
759
    $base_root = substr($base_url, 0, strlen($base_url) - strlen($parts['path']));
760
  }
761
  else {
762
    // Create base URL.
763
    $http_protocol = $is_https ? 'https' : 'http';
764
    $base_root = $http_protocol . '://' . $_SERVER['HTTP_HOST'];
765

    
766
    $base_url = $base_root;
767

    
768
    // $_SERVER['SCRIPT_NAME'] can, in contrast to $_SERVER['PHP_SELF'], not
769
    // be modified by a visitor.
770
    if ($dir = rtrim(dirname($_SERVER['SCRIPT_NAME']), '\/')) {
771
      $base_path = $dir;
772
      $base_url .= $base_path;
773
      $base_path .= '/';
774
    }
775
    else {
776
      $base_path = '/';
777
    }
778
  }
779
  $base_secure_url = str_replace('http://', 'https://', $base_url);
780
  $base_insecure_url = str_replace('https://', 'http://', $base_url);
781

    
782
  if ($cookie_domain) {
783
    // If the user specifies the cookie domain, also use it for session name.
784
    $session_name = $cookie_domain;
785
  }
786
  else {
787
    // Otherwise use $base_url as session name, without the protocol
788
    // to use the same session identifiers across HTTP and HTTPS.
789
    list( , $session_name) = explode('://', $base_url, 2);
790
    // HTTP_HOST can be modified by a visitor, but we already sanitized it
791
    // in drupal_settings_initialize().
792
    if (!empty($_SERVER['HTTP_HOST'])) {
793
      $cookie_domain = $_SERVER['HTTP_HOST'];
794
      // Strip leading periods, www., and port numbers from cookie domain.
795
      $cookie_domain = ltrim($cookie_domain, '.');
796
      if (strpos($cookie_domain, 'www.') === 0) {
797
        $cookie_domain = substr($cookie_domain, 4);
798
      }
799
      $cookie_domain = explode(':', $cookie_domain);
800
      $cookie_domain = '.' . $cookie_domain[0];
801
    }
802
  }
803
  // Per RFC 2109, cookie domains must contain at least one dot other than the
804
  // first. For hosts such as 'localhost' or IP Addresses we don't set a cookie domain.
805
  if (count(explode('.', $cookie_domain)) > 2 && !is_numeric(str_replace('.', '', $cookie_domain))) {
806
    ini_set('session.cookie_domain', $cookie_domain);
807
  }
808
  // To prevent session cookies from being hijacked, a user can configure the
809
  // SSL version of their website to only transfer session cookies via SSL by
810
  // using PHP's session.cookie_secure setting. The browser will then use two
811
  // separate session cookies for the HTTPS and HTTP versions of the site. So we
812
  // must use different session identifiers for HTTPS and HTTP to prevent a
813
  // cookie collision.
814
  if ($is_https) {
815
    ini_set('session.cookie_secure', TRUE);
816
  }
817
  $prefix = ini_get('session.cookie_secure') ? 'SSESS' : 'SESS';
818
  session_name($prefix . substr(hash('sha256', $session_name), 0, 32));
819
}
820

    
821
/**
822
 * Returns and optionally sets the filename for a system resource.
823
 *
824
 * The filename, whether provided, cached, or retrieved from the database, is
825
 * only returned if the file exists.
826
 *
827
 * This function plays a key role in allowing Drupal's resources (modules
828
 * and themes) to be located in different places depending on a site's
829
 * configuration. For example, a module 'foo' may legally be located
830
 * in any of these three places:
831
 *
832
 * modules/foo/foo.module
833
 * sites/all/modules/foo/foo.module
834
 * sites/example.com/modules/foo/foo.module
835
 *
836
 * Calling drupal_get_filename('module', 'foo') will give you one of
837
 * the above, depending on where the module is located.
838
 *
839
 * @param $type
840
 *   The type of the item (theme, theme_engine, module, profile).
841
 * @param $name
842
 *   The name of the item for which the filename is requested.
843
 * @param $filename
844
 *   The filename of the item if it is to be set explicitly rather
845
 *   than by consulting the database.
846
 * @param bool $trigger_error
847
 *   Whether to trigger an error when a file is missing or has unexpectedly
848
 *   moved. This defaults to TRUE, but can be set to FALSE by calling code that
849
 *   merely wants to check whether an item exists in the filesystem.
850
 *
851
 * @return
852
 *   The filename of the requested item or NULL if the item is not found.
853
 */
854
function drupal_get_filename($type, $name, $filename = NULL, $trigger_error = TRUE) {
855
  // The $files static variable will hold the locations of all requested files.
856
  // We can be sure that any file listed in this static variable actually
857
  // exists as all additions have gone through a file_exists() check.
858
  // The location of files will not change during the request, so do not use
859
  // drupal_static().
860
  static $files = array();
861

    
862
  // Profiles are a special case: they have a fixed location and naming.
863
  if ($type == 'profile') {
864
    $profile_filename = "profiles/$name/$name.profile";
865
    $files[$type][$name] = file_exists($profile_filename) ? $profile_filename : FALSE;
866
  }
867
  if (!isset($files[$type])) {
868
    $files[$type] = array();
869
  }
870

    
871
  if (!empty($filename) && file_exists($filename)) {
872
    // Prime the static cache with the provided filename.
873
    $files[$type][$name] = $filename;
874
  }
875
  elseif (isset($files[$type][$name])) {
876
    // This item had already been found earlier in the request, either through
877
    // priming of the static cache (for example, in system_list()), through a
878
    // lookup in the {system} table, or through a file scan (cached or not). Do
879
    // nothing.
880
  }
881
  else {
882
    // Look for the filename listed in the {system} table. Verify that we have
883
    // an active database connection before doing so, since this function is
884
    // called both before we have a database connection (i.e. during
885
    // installation) and when a database connection fails.
886
    $database_unavailable = TRUE;
887
    try {
888
      if (function_exists('db_query')) {
889
        $file = db_query("SELECT filename FROM {system} WHERE name = :name AND type = :type", array(':name' => $name, ':type' => $type))->fetchField();
890
        if ($file !== FALSE && file_exists(DRUPAL_ROOT . '/' . $file)) {
891
          $files[$type][$name] = $file;
892
        }
893
        $database_unavailable = FALSE;
894
      }
895
    }
896
    catch (Exception $e) {
897
      // The database table may not exist because Drupal is not yet installed,
898
      // the database might be down, or we may have done a non-database cache
899
      // flush while $conf['page_cache_without_database'] = TRUE and
900
      // $conf['page_cache_invoke_hooks'] = TRUE. We have a fallback for these
901
      // cases so we hide the error completely.
902
    }
903
    // Fall back to searching the filesystem if the database could not find the
904
    // file or the file does not exist at the path returned by the database.
905
    if (!isset($files[$type][$name])) {
906
      $files[$type][$name] = _drupal_get_filename_fallback($type, $name, $trigger_error, $database_unavailable);
907
    }
908
  }
909

    
910
  if (isset($files[$type][$name])) {
911
    return $files[$type][$name];
912
  }
913
}
914

    
915
/**
916
 * Performs a cached file system scan as a fallback when searching for a file.
917
 *
918
 * This function looks for the requested file by triggering a file scan,
919
 * caching the new location if the file has moved and caching the miss
920
 * if the file is missing. If a file had been marked as missing in a previous
921
 * file scan, or if it has been marked as moved and is still in the last known
922
 * location, no new file scan will be performed.
923
 *
924
 * @param string $type
925
 *   The type of the item (theme, theme_engine, module, profile).
926
 * @param string $name
927
 *   The name of the item for which the filename is requested.
928
 * @param bool $trigger_error
929
 *   Whether to trigger an error when a file is missing or has unexpectedly
930
 *   moved.
931
 * @param bool $database_unavailable
932
 *   Whether this function is being called because the Drupal database could
933
 *   not be queried for the file's location.
934
 *
935
 * @return
936
 *   The filename of the requested item or NULL if the item is not found.
937
 *
938
 * @see drupal_get_filename()
939
 */
940
function _drupal_get_filename_fallback($type, $name, $trigger_error, $database_unavailable) {
941
  $file_scans = &_drupal_file_scan_cache();
942
  $filename = NULL;
943

    
944
  // If the cache indicates that the item is missing, or we can verify that the
945
  // item exists in the location the cache says it exists in, use that.
946
  if (isset($file_scans[$type][$name]) && ($file_scans[$type][$name] === FALSE || file_exists($file_scans[$type][$name]))) {
947
    $filename = $file_scans[$type][$name];
948
  }
949
  // Otherwise, perform a new file scan to find the item.
950
  else {
951
    $filename = _drupal_get_filename_perform_file_scan($type, $name);
952
    // Update the static cache, and mark the persistent cache for updating at
953
    // the end of the page request. See drupal_file_scan_write_cache().
954
    $file_scans[$type][$name] = $filename;
955
    $file_scans['#write_cache'] = TRUE;
956
  }
957

    
958
  // If requested, trigger a user-level warning about the missing or
959
  // unexpectedly moved file. If the database was unavailable, do not trigger a
960
  // warning in the latter case, though, since if the {system} table could not
961
  // be queried there is no way to know if the location found here was
962
  // "unexpected" or not.
963
  if ($trigger_error) {
964
    $error_type = $filename === FALSE ? 'missing' : 'moved';
965
    if ($error_type == 'missing' || !$database_unavailable) {
966
      _drupal_get_filename_fallback_trigger_error($type, $name, $error_type);
967
    }
968
  }
969

    
970
  // The cache stores FALSE for files that aren't found (to be able to
971
  // distinguish them from files that have not yet been searched for), but
972
  // drupal_get_filename() expects NULL for these instead, so convert to NULL
973
  // before returning.
974
  if ($filename === FALSE) {
975
    $filename = NULL;
976
  }
977
  return $filename;
978
}
979

    
980
/**
981
 * Returns the current list of cached file system scan results.
982
 *
983
 * @return
984
 *   An associative array tracking the most recent file scan results for all
985
 *   files that have had scans performed. The keys are the type and name of the
986
 *   item that was searched for, and the values can be either:
987
 *   - Boolean FALSE if the item was not found in the file system.
988
 *   - A string pointing to the location where the item was found.
989
 */
990
function &_drupal_file_scan_cache() {
991
  $file_scans = &drupal_static(__FUNCTION__, array());
992

    
993
  // The file scan results are stored in a persistent cache (in addition to the
994
  // static cache) but because this function can be called before the
995
  // persistent cache is available, we must merge any items that were found
996
  // earlier in the page request into the results from the persistent cache.
997
  if (!isset($file_scans['#cache_merge_done'])) {
998
    try {
999
      if (function_exists('cache_get')) {
1000
        $cache = cache_get('_drupal_file_scan_cache', 'cache_bootstrap');
1001
        if (!empty($cache->data)) {
1002
          // File scan results from the current request should take precedence
1003
          // over the results from the persistent cache, since they are newer.
1004
          $file_scans = drupal_array_merge_deep($cache->data, $file_scans);
1005
        }
1006
        // Set a flag to indicate that the persistent cache does not need to be
1007
        // merged again.
1008
        $file_scans['#cache_merge_done'] = TRUE;
1009
      }
1010
    }
1011
    catch (Exception $e) {
1012
      // Hide the error.
1013
    }
1014
  }
1015

    
1016
  return $file_scans;
1017
}
1018

    
1019
/**
1020
 * Performs a file system scan to search for a system resource.
1021
 *
1022
 * @param $type
1023
 *   The type of the item (theme, theme_engine, module, profile).
1024
 * @param $name
1025
 *   The name of the item for which the filename is requested.
1026
 *
1027
 * @return
1028
 *   The filename of the requested item or FALSE if the item is not found.
1029
 *
1030
 * @see drupal_get_filename()
1031
 * @see _drupal_get_filename_fallback()
1032
 */
1033
function _drupal_get_filename_perform_file_scan($type, $name) {
1034
  // The location of files will not change during the request, so do not use
1035
  // drupal_static().
1036
  static $dirs = array(), $files = array();
1037

    
1038
  // We have a consistent directory naming: modules, themes...
1039
  $dir = $type . 's';
1040
  if ($type == 'theme_engine') {
1041
    $dir = 'themes/engines';
1042
    $extension = 'engine';
1043
  }
1044
  elseif ($type == 'theme') {
1045
    $extension = 'info';
1046
  }
1047
  else {
1048
    $extension = $type;
1049
  }
1050

    
1051
  // Check if we had already scanned this directory/extension combination.
1052
  if (!isset($dirs[$dir][$extension])) {
1053
    // Log that we have now scanned this directory/extension combination
1054
    // into a static variable so as to prevent unnecessary file scans.
1055
    $dirs[$dir][$extension] = TRUE;
1056
    if (!function_exists('drupal_system_listing')) {
1057
      require_once DRUPAL_ROOT . '/includes/common.inc';
1058
    }
1059
    // Scan the appropriate directories for all files with the requested
1060
    // extension, not just the file we are currently looking for. This
1061
    // prevents unnecessary scans from being repeated when this function is
1062
    // called more than once in the same page request.
1063
    $matches = drupal_system_listing("/^" . DRUPAL_PHP_FUNCTION_PATTERN . "\.$extension$/", $dir, 'name', 0);
1064
    foreach ($matches as $matched_name => $file) {
1065
      // Log the locations found in the file scan into a static variable.
1066
      $files[$type][$matched_name] = $file->uri;
1067
    }
1068
  }
1069

    
1070
  // Return the results of the file system scan, or FALSE to indicate the file
1071
  // was not found.
1072
  return isset($files[$type][$name]) ? $files[$type][$name] : FALSE;
1073
}
1074

    
1075
/**
1076
 * Triggers a user-level warning for missing or unexpectedly moved files.
1077
 *
1078
 * @param $type
1079
 *   The type of the item (theme, theme_engine, module, profile).
1080
 * @param $name
1081
 *   The name of the item for which the filename is requested.
1082
 * @param $error_type
1083
 *   The type of the error ('missing' or 'moved').
1084
 *
1085
 * @see drupal_get_filename()
1086
 * @see _drupal_get_filename_fallback()
1087
 */
1088
function _drupal_get_filename_fallback_trigger_error($type, $name, $error_type) {
1089
  // Hide messages due to known bugs that will appear on a lot of sites.
1090
  // @todo Remove this in https://www.drupal.org/node/2383823
1091
  if (empty($name)) {
1092
    return;
1093
  }
1094

    
1095
  // Make sure we only show any missing or moved file errors only once per
1096
  // request.
1097
  static $errors_triggered = array();
1098
  if (empty($errors_triggered[$type][$name][$error_type])) {
1099
    // Use _drupal_trigger_error_with_delayed_logging() here since these are
1100
    // triggered during low-level operations that cannot necessarily be
1101
    // interrupted by a watchdog() call.
1102
    if ($error_type == 'missing') {
1103
      _drupal_trigger_error_with_delayed_logging(format_string('The following @type is missing from the file system: %name. For information about how to fix this, see <a href="@documentation">the documentation page</a>.', array('@type' => $type, '%name' => $name, '@documentation' => 'https://www.drupal.org/node/2487215')), E_USER_WARNING);
1104
    }
1105
    elseif ($error_type == 'moved') {
1106
      _drupal_trigger_error_with_delayed_logging(format_string('The following @type has moved within the file system: %name. In order to fix this, clear caches or put the @type back in its original location. For more information, see <a href="@documentation">the documentation page</a>.', array('@type' => $type, '%name' => $name, '@documentation' => 'https://www.drupal.org/node/2487215')), E_USER_WARNING);
1107
    }
1108
    $errors_triggered[$type][$name][$error_type] = TRUE;
1109
  }
1110
}
1111

    
1112
/**
1113
 * Invokes trigger_error() with logging delayed until the end of the request.
1114
 *
1115
 * This is an alternative to PHP's trigger_error() function which can be used
1116
 * during low-level Drupal core operations that need to avoid being interrupted
1117
 * by a watchdog() call.
1118
 *
1119
 * Normally, Drupal's error handler calls watchdog() in response to a
1120
 * trigger_error() call. However, this invokes hook_watchdog() which can run
1121
 * arbitrary code. If the trigger_error() happens in the middle of an
1122
 * operation such as a rebuild operation which should not be interrupted by
1123
 * arbitrary code, that could potentially break or trigger the rebuild again.
1124
 * This function protects against that by delaying the watchdog() call until
1125
 * the end of the current page request.
1126
 *
1127
 * This is an internal function which should only be called by low-level Drupal
1128
 * core functions. It may be removed in a future Drupal 7 release.
1129
 *
1130
 * @param string $error_msg
1131
 *   The error message to trigger. As with trigger_error() itself, this is
1132
 *   limited to 1024 bytes; additional characters beyond that will be removed.
1133
 * @param int $error_type
1134
 *   (optional) The type of error. This should be one of the E_USER family of
1135
 *   constants. As with trigger_error() itself, this defaults to E_USER_NOTICE
1136
 *   if not provided.
1137
 *
1138
 * @see _drupal_log_error()
1139
 */
1140
function _drupal_trigger_error_with_delayed_logging($error_msg, $error_type = E_USER_NOTICE) {
1141
  $delay_logging = &drupal_static(__FUNCTION__, FALSE);
1142
  $delay_logging = TRUE;
1143
  trigger_error($error_msg, $error_type);
1144
  $delay_logging = FALSE;
1145
}
1146

    
1147
/**
1148
 * Writes the file scan cache to the persistent cache.
1149
 *
1150
 * This cache stores all files marked as missing or moved after a file scan
1151
 * to prevent unnecessary file scans in subsequent requests. This cache is
1152
 * cleared in system_list_reset() (i.e. after a module/theme rebuild).
1153
 */
1154
function drupal_file_scan_write_cache() {
1155
  // Only write to the persistent cache if requested, and if we know that any
1156
  // data previously in the cache was successfully loaded and merged in by
1157
  // _drupal_file_scan_cache().
1158
  $file_scans = &_drupal_file_scan_cache();
1159
  if (isset($file_scans['#write_cache']) && isset($file_scans['#cache_merge_done'])) {
1160
    unset($file_scans['#write_cache']);
1161
    cache_set('_drupal_file_scan_cache', $file_scans, 'cache_bootstrap');
1162
  }
1163
}
1164

    
1165
/**
1166
 * Loads the persistent variable table.
1167
 *
1168
 * The variable table is composed of values that have been saved in the table
1169
 * with variable_set() as well as those explicitly specified in the
1170
 * configuration file.
1171
 */
1172
function variable_initialize($conf = array()) {
1173
  // NOTE: caching the variables improves performance by 20% when serving
1174
  // cached pages.
1175
  if ($cached = cache_get('variables', 'cache_bootstrap')) {
1176
    $variables = $cached->data;
1177
  }
1178
  else {
1179
    // Cache miss. Avoid a stampede.
1180
    $name = 'variable_init';
1181
    if (!lock_acquire($name, 1)) {
1182
      // Another request is building the variable cache.
1183
      // Wait, then re-run this function.
1184
      lock_wait($name);
1185
      return variable_initialize($conf);
1186
    }
1187
    else {
1188
      // Proceed with variable rebuild.
1189
      $variables = array_map('unserialize', db_query('SELECT name, value FROM {variable}')->fetchAllKeyed());
1190
      cache_set('variables', $variables, 'cache_bootstrap');
1191
      lock_release($name);
1192
    }
1193
  }
1194

    
1195
  foreach ($conf as $name => $value) {
1196
    $variables[$name] = $value;
1197
  }
1198

    
1199
  return $variables;
1200
}
1201

    
1202
/**
1203
 * Returns a persistent variable.
1204
 *
1205
 * Case-sensitivity of the variable_* functions depends on the database
1206
 * collation used. To avoid problems, always use lower case for persistent
1207
 * variable names.
1208
 *
1209
 * @param $name
1210
 *   The name of the variable to return.
1211
 * @param $default
1212
 *   The default value to use if this variable has never been set.
1213
 *
1214
 * @return
1215
 *   The value of the variable. Unserialization is taken care of as necessary.
1216
 *
1217
 * @see variable_del()
1218
 * @see variable_set()
1219
 */
1220
function variable_get($name, $default = NULL) {
1221
  global $conf;
1222

    
1223
  return isset($conf[$name]) ? $conf[$name] : $default;
1224
}
1225

    
1226
/**
1227
 * Sets a persistent variable.
1228
 *
1229
 * Case-sensitivity of the variable_* functions depends on the database
1230
 * collation used. To avoid problems, always use lower case for persistent
1231
 * variable names.
1232
 *
1233
 * @param $name
1234
 *   The name of the variable to set.
1235
 * @param $value
1236
 *   The value to set. This can be any PHP data type; these functions take care
1237
 *   of serialization as necessary.
1238
 *
1239
 * @see variable_del()
1240
 * @see variable_get()
1241
 */
1242
function variable_set($name, $value) {
1243
  global $conf;
1244

    
1245
  db_merge('variable')->key(array('name' => $name))->fields(array('value' => serialize($value)))->execute();
1246

    
1247
  cache_clear_all('variables', 'cache_bootstrap');
1248

    
1249
  $conf[$name] = $value;
1250
}
1251

    
1252
/**
1253
 * Unsets a persistent variable.
1254
 *
1255
 * Case-sensitivity of the variable_* functions depends on the database
1256
 * collation used. To avoid problems, always use lower case for persistent
1257
 * variable names.
1258
 *
1259
 * @param $name
1260
 *   The name of the variable to undefine.
1261
 *
1262
 * @see variable_get()
1263
 * @see variable_set()
1264
 */
1265
function variable_del($name) {
1266
  global $conf;
1267

    
1268
  db_delete('variable')
1269
    ->condition('name', $name)
1270
    ->execute();
1271
  cache_clear_all('variables', 'cache_bootstrap');
1272

    
1273
  unset($conf[$name]);
1274
}
1275

    
1276
/**
1277
 * Retrieves the current page from the cache.
1278
 *
1279
 * Note: we do not serve cached pages to authenticated users, or to anonymous
1280
 * users when $_SESSION is non-empty. $_SESSION may contain status messages
1281
 * from a form submission, the contents of a shopping cart, or other user-
1282
 * specific content that should not be cached and displayed to other users.
1283
 *
1284
 * @param $check_only
1285
 *   (optional) Set to TRUE to only return whether a previous call found a
1286
 *   cache entry.
1287
 *
1288
 * @return
1289
 *   The cache object, if the page was found in the cache, NULL otherwise.
1290
 */
1291
function drupal_page_get_cache($check_only = FALSE) {
1292
  global $base_root;
1293
  static $cache_hit = FALSE;
1294

    
1295
  if ($check_only) {
1296
    return $cache_hit;
1297
  }
1298

    
1299
  if (drupal_page_is_cacheable()) {
1300
    $cache = cache_get($base_root . request_uri(), 'cache_page');
1301
    if ($cache !== FALSE) {
1302
      $cache_hit = TRUE;
1303
    }
1304
    return $cache;
1305
  }
1306
}
1307

    
1308
/**
1309
 * Determines the cacheability of the current page.
1310
 *
1311
 * @param $allow_caching
1312
 *   Set to FALSE if you want to prevent this page from being cached.
1313
 *
1314
 * @return
1315
 *   TRUE if the current page can be cached, FALSE otherwise.
1316
 */
1317
function drupal_page_is_cacheable($allow_caching = NULL) {
1318
  $allow_caching_static = &drupal_static(__FUNCTION__, TRUE);
1319
  if (isset($allow_caching)) {
1320
    $allow_caching_static = $allow_caching;
1321
  }
1322

    
1323
  return $allow_caching_static && ($_SERVER['REQUEST_METHOD'] == 'GET' || $_SERVER['REQUEST_METHOD'] == 'HEAD')
1324
    && !drupal_is_cli();
1325
}
1326

    
1327
/**
1328
 * Invokes a bootstrap hook in all bootstrap modules that implement it.
1329
 *
1330
 * @param $hook
1331
 *   The name of the bootstrap hook to invoke.
1332
 *
1333
 * @see bootstrap_hooks()
1334
 */
1335
function bootstrap_invoke_all($hook) {
1336
  // Bootstrap modules should have been loaded when this function is called, so
1337
  // we don't need to tell module_list() to reset its internal list (and we
1338
  // therefore leave the first parameter at its default value of FALSE). We
1339
  // still pass in TRUE for the second parameter, though; in case this is the
1340
  // first time during the bootstrap that module_list() is called, we want to
1341
  // make sure that its internal cache is primed with the bootstrap modules
1342
  // only.
1343
  foreach (module_list(FALSE, TRUE) as $module) {
1344
    drupal_load('module', $module);
1345
    module_invoke($module, $hook);
1346
  }
1347
}
1348

    
1349
/**
1350
 * Includes a file with the provided type and name.
1351
 *
1352
 * This prevents including a theme, engine, module, etc., more than once.
1353
 *
1354
 * @param $type
1355
 *   The type of item to load (i.e. theme, theme_engine, module).
1356
 * @param $name
1357
 *   The name of the item to load.
1358
 *
1359
 * @return
1360
 *   TRUE if the item is loaded or has already been loaded.
1361
 */
1362
function drupal_load($type, $name) {
1363
  // Once a file is included this can't be reversed during a request so do not
1364
  // use drupal_static() here.
1365
  static $files = array();
1366

    
1367
  if (isset($files[$type][$name])) {
1368
    return TRUE;
1369
  }
1370

    
1371
  $filename = drupal_get_filename($type, $name);
1372

    
1373
  if ($filename) {
1374
    include_once DRUPAL_ROOT . '/' . $filename;
1375
    $files[$type][$name] = TRUE;
1376

    
1377
    return TRUE;
1378
  }
1379

    
1380
  return FALSE;
1381
}
1382

    
1383
/**
1384
 * Sets an HTTP response header for the current page.
1385
 *
1386
 * Note: When sending a Content-Type header, always include a 'charset' type,
1387
 * too. This is necessary to avoid security bugs (e.g. UTF-7 XSS).
1388
 *
1389
 * @param $name
1390
 *   The HTTP header name, or the special 'Status' header name.
1391
 * @param $value
1392
 *   The HTTP header value; if equal to FALSE, the specified header is unset.
1393
 *   If $name is 'Status', this is expected to be a status code followed by a
1394
 *   reason phrase, e.g. "404 Not Found".
1395
 * @param $append
1396
 *   Whether to append the value to an existing header or to replace it.
1397
 */
1398
function drupal_add_http_header($name, $value, $append = FALSE) {
1399
  // The headers as name/value pairs.
1400
  $headers = &drupal_static('drupal_http_headers', array());
1401

    
1402
  $name_lower = strtolower($name);
1403
  _drupal_set_preferred_header_name($name);
1404

    
1405
  if ($value === FALSE) {
1406
    $headers[$name_lower] = FALSE;
1407
  }
1408
  elseif (isset($headers[$name_lower]) && $append) {
1409
    // Multiple headers with identical names may be combined using comma (RFC
1410
    // 2616, section 4.2).
1411
    $headers[$name_lower] .= ',' . $value;
1412
  }
1413
  else {
1414
    $headers[$name_lower] = $value;
1415
  }
1416
  drupal_send_headers(array($name => $headers[$name_lower]), TRUE);
1417
}
1418

    
1419
/**
1420
 * Gets the HTTP response headers for the current page.
1421
 *
1422
 * @param $name
1423
 *   An HTTP header name. If omitted, all headers are returned as name/value
1424
 *   pairs. If an array value is FALSE, the header has been unset.
1425
 *
1426
 * @return
1427
 *   A string containing the header value, or FALSE if the header has been set,
1428
 *   or NULL if the header has not been set.
1429
 */
1430
function drupal_get_http_header($name = NULL) {
1431
  $headers = &drupal_static('drupal_http_headers', array());
1432
  if (isset($name)) {
1433
    $name = strtolower($name);
1434
    return isset($headers[$name]) ? $headers[$name] : NULL;
1435
  }
1436
  else {
1437
    return $headers;
1438
  }
1439
}
1440

    
1441
/**
1442
 * Sets the preferred name for the HTTP header.
1443
 *
1444
 * Header names are case-insensitive, but for maximum compatibility they should
1445
 * follow "common form" (see RFC 2617, section 4.2).
1446
 */
1447
function _drupal_set_preferred_header_name($name = NULL) {
1448
  static $header_names = array();
1449

    
1450
  if (!isset($name)) {
1451
    return $header_names;
1452
  }
1453
  $header_names[strtolower($name)] = $name;
1454
}
1455

    
1456
/**
1457
 * Sends the HTTP response headers that were previously set, adding defaults.
1458
 *
1459
 * Headers are set in drupal_add_http_header(). Default headers are not set
1460
 * if they have been replaced or unset using drupal_add_http_header().
1461
 *
1462
 * @param array $default_headers
1463
 *   (optional) An array of headers as name/value pairs.
1464
 * @param bool $only_default
1465
 *   (optional) If TRUE and headers have already been sent, send only the
1466
 *   specified headers.
1467
 */
1468
function drupal_send_headers($default_headers = array(), $only_default = FALSE) {
1469
  $headers_sent = &drupal_static(__FUNCTION__, FALSE);
1470
  $headers = drupal_get_http_header();
1471
  if ($only_default && $headers_sent) {
1472
    $headers = array();
1473
  }
1474
  $headers_sent = TRUE;
1475

    
1476
  $header_names = _drupal_set_preferred_header_name();
1477
  foreach ($default_headers as $name => $value) {
1478
    $name_lower = strtolower($name);
1479
    if (!isset($headers[$name_lower])) {
1480
      $headers[$name_lower] = $value;
1481
      $header_names[$name_lower] = $name;
1482
    }
1483
  }
1484
  foreach ($headers as $name_lower => $value) {
1485
    if ($name_lower == 'status') {
1486
      header($_SERVER['SERVER_PROTOCOL'] . ' ' . $value);
1487
    }
1488
    // Skip headers that have been unset.
1489
    elseif ($value !== FALSE) {
1490
      header($header_names[$name_lower] . ': ' . $value);
1491
    }
1492
  }
1493
}
1494

    
1495
/**
1496
 * Sets HTTP headers in preparation for a page response.
1497
 *
1498
 * Authenticated users are always given a 'no-cache' header, and will fetch a
1499
 * fresh page on every request. This prevents authenticated users from seeing
1500
 * locally cached pages.
1501
 *
1502
 * ETag and Last-Modified headers are not set per default for authenticated
1503
 * users so that browsers do not send If-Modified-Since headers from
1504
 * authenticated user pages. drupal_serve_page_from_cache() will set appropriate
1505
 * ETag and Last-Modified headers for cached pages.
1506
 *
1507
 * @see drupal_page_set_cache()
1508
 */
1509
function drupal_page_header() {
1510
  $headers_sent = &drupal_static(__FUNCTION__, FALSE);
1511
  if ($headers_sent) {
1512
    return TRUE;
1513
  }
1514
  $headers_sent = TRUE;
1515

    
1516
  $default_headers = array(
1517
    'Expires' => 'Sun, 19 Nov 1978 05:00:00 GMT',
1518
    'Cache-Control' => 'no-cache, must-revalidate',
1519
    // Prevent browsers from sniffing a response and picking a MIME type
1520
    // different from the declared content-type, since that can lead to
1521
    // XSS and other vulnerabilities.
1522
    'X-Content-Type-Options' => 'nosniff',
1523
  );
1524
  drupal_send_headers($default_headers);
1525
}
1526

    
1527
/**
1528
 * Sets HTTP headers in preparation for a cached page response.
1529
 *
1530
 * The headers allow as much as possible in proxies and browsers without any
1531
 * particular knowledge about the pages. Modules can override these headers
1532
 * using drupal_add_http_header().
1533
 *
1534
 * If the request is conditional (using If-Modified-Since and If-None-Match),
1535
 * and the conditions match those currently in the cache, a 304 Not Modified
1536
 * response is sent.
1537
 */
1538
function drupal_serve_page_from_cache(stdClass $cache) {
1539
  // Negotiate whether to use compression.
1540
  $page_compression = !empty($cache->data['page_compressed']);
1541
  $return_compressed = $page_compression && isset($_SERVER['HTTP_ACCEPT_ENCODING']) && strpos($_SERVER['HTTP_ACCEPT_ENCODING'], 'gzip') !== FALSE;
1542

    
1543
  // Get headers set in hook_boot(). Keys are lower-case.
1544
  $hook_boot_headers = drupal_get_http_header();
1545

    
1546
  // Headers generated in this function, that may be replaced or unset using
1547
  // drupal_add_http_headers(). Keys are mixed-case.
1548
  $default_headers = array();
1549

    
1550
  foreach ($cache->data['headers'] as $name => $value) {
1551
    // In the case of a 304 response, certain headers must be sent, and the
1552
    // remaining may not (see RFC 2616, section 10.3.5). Do not override
1553
    // headers set in hook_boot().
1554
    $name_lower = strtolower($name);
1555
    if (in_array($name_lower, array('content-location', 'expires', 'cache-control', 'vary')) && !isset($hook_boot_headers[$name_lower])) {
1556
      drupal_add_http_header($name, $value);
1557
      unset($cache->data['headers'][$name]);
1558
    }
1559
  }
1560

    
1561
  // If the client sent a session cookie, a cached copy will only be served
1562
  // to that one particular client due to Vary: Cookie. Thus, do not set
1563
  // max-age > 0, allowing the page to be cached by external proxies, when a
1564
  // session cookie is present unless the Vary header has been replaced or
1565
  // unset in hook_boot().
1566
  $max_age = !isset($_COOKIE[session_name()]) || isset($hook_boot_headers['vary']) ? variable_get('page_cache_maximum_age', 0) : 0;
1567
  $default_headers['Cache-Control'] = 'public, max-age=' . $max_age;
1568

    
1569
  // Entity tag should change if the output changes.
1570
  $etag = '"' . $cache->created . '-' . intval($return_compressed) . '"';
1571
  header('Etag: ' . $etag);
1572

    
1573
  // See if the client has provided the required HTTP headers.
1574
  $if_modified_since = isset($_SERVER['HTTP_IF_MODIFIED_SINCE']) ? strtotime($_SERVER['HTTP_IF_MODIFIED_SINCE']) : FALSE;
1575
  $if_none_match = isset($_SERVER['HTTP_IF_NONE_MATCH']) ? stripslashes($_SERVER['HTTP_IF_NONE_MATCH']) : FALSE;
1576

    
1577
  if ($if_modified_since && $if_none_match
1578
      && $if_none_match == $etag // etag must match
1579
      && $if_modified_since == $cache->created) {  // if-modified-since must match
1580
    header($_SERVER['SERVER_PROTOCOL'] . ' 304 Not Modified');
1581
    drupal_send_headers($default_headers);
1582
    return;
1583
  }
1584

    
1585
  // Send the remaining headers.
1586
  foreach ($cache->data['headers'] as $name => $value) {
1587
    drupal_add_http_header($name, $value);
1588
  }
1589

    
1590
  $default_headers['Last-Modified'] = gmdate(DATE_RFC7231, $cache->created);
1591

    
1592
  // HTTP/1.0 proxies does not support the Vary header, so prevent any caching
1593
  // by sending an Expires date in the past. HTTP/1.1 clients ignores the
1594
  // Expires header if a Cache-Control: max-age= directive is specified (see RFC
1595
  // 2616, section 14.9.3).
1596
  $default_headers['Expires'] = 'Sun, 19 Nov 1978 05:00:00 GMT';
1597

    
1598
  drupal_send_headers($default_headers);
1599

    
1600
  // Allow HTTP proxies to cache pages for anonymous users without a session
1601
  // cookie. The Vary header is used to indicates the set of request-header
1602
  // fields that fully determines whether a cache is permitted to use the
1603
  // response to reply to a subsequent request for a given URL without
1604
  // revalidation. If a Vary header has been set in hook_boot(), it is assumed
1605
  // that the module knows how to cache the page.
1606
  if (!isset($hook_boot_headers['vary']) && !variable_get('omit_vary_cookie')) {
1607
    header('Vary: Cookie');
1608
  }
1609

    
1610
  if ($page_compression) {
1611
    header('Vary: Accept-Encoding', FALSE);
1612
    // If page_compression is enabled, the cache contains gzipped data.
1613
    if ($return_compressed) {
1614
      // $cache->data['body'] is already gzip'ed, so make sure
1615
      // zlib.output_compression does not compress it once more.
1616
      ini_set('zlib.output_compression', '0');
1617
      header('Content-Encoding: gzip');
1618
    }
1619
    else {
1620
      // The client does not support compression, so unzip the data in the
1621
      // cache. Strip the gzip header and run uncompress.
1622
      $cache->data['body'] = gzinflate(substr(substr($cache->data['body'], 10), 0, -8));
1623
    }
1624
  }
1625

    
1626
  // Print the page.
1627
  print $cache->data['body'];
1628
}
1629

    
1630
/**
1631
 * Defines the critical hooks that force modules to always be loaded.
1632
 */
1633
function bootstrap_hooks() {
1634
  return array('boot', 'exit', 'watchdog', 'language_init');
1635
}
1636

    
1637
/**
1638
 * Unserializes and appends elements from a serialized string.
1639
 *
1640
 * @param $obj
1641
 *   The object to which the elements are appended.
1642
 * @param $field
1643
 *   The attribute of $obj whose value should be unserialized.
1644
 */
1645
function drupal_unpack($obj, $field = 'data') {
1646
  if ($obj->$field && $data = unserialize($obj->$field)) {
1647
    foreach ($data as $key => $value) {
1648
      if (!empty($key) && !isset($obj->$key)) {
1649
        $obj->$key = $value;
1650
      }
1651
    }
1652
  }
1653
  return $obj;
1654
}
1655

    
1656
/**
1657
 * Translates a string to the current language or to a given language.
1658
 *
1659
 * The t() function serves two purposes. First, at run-time it translates
1660
 * user-visible text into the appropriate language. Second, various mechanisms
1661
 * that figure out what text needs to be translated work off t() -- the text
1662
 * inside t() calls is added to the database of strings to be translated.
1663
 * These strings are expected to be in English, so the first argument should
1664
 * always be in English. To enable a fully-translatable site, it is important
1665
 * that all human-readable text that will be displayed on the site or sent to
1666
 * a user is passed through the t() function, or a related function. See the
1667
 * @link http://drupal.org/node/322729 Localization API @endlink pages for
1668
 * more information, including recommendations on how to break up or not
1669
 * break up strings for translation.
1670
 *
1671
 * @section sec_translating_vars Translating Variables
1672
 * You should never use t() to translate variables, such as calling
1673
 * @code t($text); @endcode, unless the text that the variable holds has been
1674
 * passed through t() elsewhere (e.g., $text is one of several translated
1675
 * literal strings in an array). It is especially important never to call
1676
 * @code t($user_text); @endcode, where $user_text is some text that a user
1677
 * entered - doing that can lead to cross-site scripting and other security
1678
 * problems. However, you can use variable substitution in your string, to put
1679
 * variable text such as user names or link URLs into translated text. Variable
1680
 * substitution looks like this:
1681
 * @code
1682
 * $text = t("@name's blog", array('@name' => format_username($account)));
1683
 * @endcode
1684
 * Basically, you can put variables like @name into your string, and t() will
1685
 * substitute their sanitized values at translation time. (See the
1686
 * Localization API pages referenced above and the documentation of
1687
 * format_string() for details about how to define variables in your string.)
1688
 * Translators can then rearrange the string as necessary for the language
1689
 * (e.g., in Spanish, it might be "blog de @name").
1690
 *
1691
 * @section sec_alt_funcs_install Use During Installation Phase
1692
 * During the Drupal installation phase, some resources used by t() wil not be
1693
 * available to code that needs localization. See st() and get_t() for
1694
 * alternatives.
1695
 *
1696
 * @section sec_context String context
1697
 * Matching source strings are normally only translated once, and the same
1698
 * translation is used everywhere that has a matching string. However, in some
1699
 * cases, a certain English source string needs to have multiple translations.
1700
 * One example of this is the string "May", which could be used as either a
1701
 * full month name or a 3-letter abbreviated month. In other languages where
1702
 * the month name for May has more than 3 letters, you would need to provide
1703
 * two different translations (one for the full name and one abbreviated), and
1704
 * the correct form would need to be chosen, depending on how "May" is being
1705
 * used. To facilitate this, the "May" string should be provided with two
1706
 * different contexts in the $options parameter when calling t(). For example:
1707
 * @code
1708
 * t('May', array(), array('context' => 'Long month name')
1709
 * t('May', array(), array('context' => 'Abbreviated month name')
1710
 * @endcode
1711
 * See https://localize.drupal.org/node/2109 for more information.
1712
 *
1713
 * @param $string
1714
 *   A string containing the English string to translate.
1715
 * @param $args
1716
 *   An associative array of replacements to make after translation. Based
1717
 *   on the first character of the key, the value is escaped and/or themed.
1718
 *   See format_string() for details.
1719
 * @param $options
1720
 *   An associative array of additional options, with the following elements:
1721
 *   - 'langcode' (defaults to the current language): The language code to
1722
 *     translate to a language other than what is used to display the page.
1723
 *   - 'context' (defaults to the empty context): A string giving the context
1724
 *     that the source string belongs to. See @ref sec_context above for more
1725
 *     information.
1726
 *
1727
 * @return
1728
 *   The translated string.
1729
 *
1730
 * @see st()
1731
 * @see get_t()
1732
 * @see format_string()
1733
 * @ingroup sanitization
1734
 */
1735
function t($string, array $args = array(), array $options = array()) {
1736
  global $language;
1737
  static $custom_strings;
1738

    
1739
  // Merge in default.
1740
  if (empty($options['langcode'])) {
1741
    $options['langcode'] = isset($language->language) ? $language->language : 'en';
1742
  }
1743
  if (empty($options['context'])) {
1744
    $options['context'] = '';
1745
  }
1746

    
1747
  // First, check for an array of customized strings. If present, use the array
1748
  // *instead of* database lookups. This is a high performance way to provide a
1749
  // handful of string replacements. See settings.php for examples.
1750
  // Cache the $custom_strings variable to improve performance.
1751
  if (!isset($custom_strings[$options['langcode']])) {
1752
    $custom_strings[$options['langcode']] = variable_get('locale_custom_strings_' . $options['langcode'], array());
1753
  }
1754
  // Custom strings work for English too, even if locale module is disabled.
1755
  if (isset($custom_strings[$options['langcode']][$options['context']][$string])) {
1756
    $string = $custom_strings[$options['langcode']][$options['context']][$string];
1757
  }
1758
  // Translate with locale module if enabled.
1759
  elseif ($options['langcode'] != 'en' && function_exists('locale')) {
1760
    $string = locale($string, $options['context'], $options['langcode']);
1761
  }
1762
  if (empty($args)) {
1763
    return $string;
1764
  }
1765
  else {
1766
    return format_string($string, $args);
1767
  }
1768
}
1769

    
1770
/**
1771
 * Formats a string for HTML display by replacing variable placeholders.
1772
 *
1773
 * This function replaces variable placeholders in a string with the requested
1774
 * values and escapes the values so they can be safely displayed as HTML. It
1775
 * should be used on any unknown text that is intended to be printed to an HTML
1776
 * page (especially text that may have come from untrusted users, since in that
1777
 * case it prevents cross-site scripting and other security problems).
1778
 *
1779
 * In most cases, you should use t() rather than calling this function
1780
 * directly, since it will translate the text (on non-English-only sites) in
1781
 * addition to formatting it.
1782
 *
1783
 * @param $string
1784
 *   A string containing placeholders.
1785
 * @param $args
1786
 *   An associative array of replacements to make. Occurrences in $string of
1787
 *   any key in $args are replaced with the corresponding value, after optional
1788
 *   sanitization and formatting. The type of sanitization and formatting
1789
 *   depends on the first character of the key:
1790
 *   - @variable: Escaped to HTML using check_plain(). Use this as the default
1791
 *     choice for anything displayed on a page on the site.
1792
 *   - %variable: Escaped to HTML and formatted using drupal_placeholder(),
1793
 *     which makes it display as <em>emphasized</em> text.
1794
 *   - !variable: Inserted as is, with no sanitization or formatting. Only use
1795
 *     this for text that has already been prepared for HTML display (for
1796
 *     example, user-supplied text that has already been run through
1797
 *     check_plain() previously, or is expected to contain some limited HTML
1798
 *     tags and has already been run through filter_xss() previously).
1799
 *
1800
 * @see t()
1801
 * @ingroup sanitization
1802
 */
1803
function format_string($string, array $args = array()) {
1804
  // Transform arguments before inserting them.
1805
  foreach ($args as $key => $value) {
1806
    switch ($key[0]) {
1807
      case '@':
1808
        // Escaped only.
1809
        $args[$key] = check_plain($value);
1810
        break;
1811

    
1812
      case '%':
1813
      default:
1814
        // Escaped and placeholder.
1815
        $args[$key] = drupal_placeholder($value);
1816
        break;
1817

    
1818
      case '!':
1819
        // Pass-through.
1820
    }
1821
  }
1822
  return strtr($string, $args);
1823
}
1824

    
1825
/**
1826
 * Encodes special characters in a plain-text string for display as HTML.
1827
 *
1828
 * Also validates strings as UTF-8 to prevent cross site scripting attacks on
1829
 * Internet Explorer 6.
1830
 *
1831
 * @param string $text
1832
 *   The text to be checked or processed.
1833
 *
1834
 * @return string
1835
 *   An HTML safe version of $text. If $text is not valid UTF-8, an empty string
1836
 *   is returned and, on PHP < 5.4, a warning may be issued depending on server
1837
 *   configuration (see @link https://bugs.php.net/bug.php?id=47494 @endlink).
1838
 *
1839
 * @see drupal_validate_utf8()
1840
 * @ingroup sanitization
1841
 */
1842
function check_plain($text) {
1843
  return htmlspecialchars($text, ENT_QUOTES, 'UTF-8');
1844
}
1845

    
1846
/**
1847
 * Checks whether a string is valid UTF-8.
1848
 *
1849
 * All functions designed to filter input should use drupal_validate_utf8
1850
 * to ensure they operate on valid UTF-8 strings to prevent bypass of the
1851
 * filter.
1852
 *
1853
 * When text containing an invalid UTF-8 lead byte (0xC0 - 0xFF) is presented
1854
 * as UTF-8 to Internet Explorer 6, the program may misinterpret subsequent
1855
 * bytes. When these subsequent bytes are HTML control characters such as
1856
 * quotes or angle brackets, parts of the text that were deemed safe by filters
1857
 * end up in locations that are potentially unsafe; An onerror attribute that
1858
 * is outside of a tag, and thus deemed safe by a filter, can be interpreted
1859
 * by the browser as if it were inside the tag.
1860
 *
1861
 * The function does not return FALSE for strings containing character codes
1862
 * above U+10FFFF, even though these are prohibited by RFC 3629.
1863
 *
1864
 * @param $text
1865
 *   The text to check.
1866
 *
1867
 * @return
1868
 *   TRUE if the text is valid UTF-8, FALSE if not.
1869
 */
1870
function drupal_validate_utf8($text) {
1871
  if (strlen($text) == 0) {
1872
    return TRUE;
1873
  }
1874
  // With the PCRE_UTF8 modifier 'u', preg_match() fails silently on strings
1875
  // containing invalid UTF-8 byte sequences. It does not reject character
1876
  // codes above U+10FFFF (represented by 4 or more octets), though.
1877
  return (preg_match('/^./us', $text) == 1);
1878
}
1879

    
1880
/**
1881
 * Returns the equivalent of Apache's $_SERVER['REQUEST_URI'] variable.
1882
 *
1883
 * Because $_SERVER['REQUEST_URI'] is only available on Apache, we generate an
1884
 * equivalent using other environment variables.
1885
 */
1886
function request_uri() {
1887
  if (isset($_SERVER['REQUEST_URI'])) {
1888
    $uri = $_SERVER['REQUEST_URI'];
1889
  }
1890
  else {
1891
    if (isset($_SERVER['argv'])) {
1892
      $uri = $_SERVER['SCRIPT_NAME'] . '?' . $_SERVER['argv'][0];
1893
    }
1894
    elseif (isset($_SERVER['QUERY_STRING'])) {
1895
      $uri = $_SERVER['SCRIPT_NAME'] . '?' . $_SERVER['QUERY_STRING'];
1896
    }
1897
    else {
1898
      $uri = $_SERVER['SCRIPT_NAME'];
1899
    }
1900
  }
1901
  // Prevent multiple slashes to avoid cross site requests via the Form API.
1902
  $uri = '/' . ltrim($uri, '/');
1903

    
1904
  return $uri;
1905
}
1906

    
1907
/**
1908
 * Logs an exception.
1909
 *
1910
 * This is a wrapper function for watchdog() which automatically decodes an
1911
 * exception.
1912
 *
1913
 * @param $type
1914
 *   The category to which this message belongs.
1915
 * @param $exception
1916
 *   The exception that is going to be logged.
1917
 * @param $message
1918
 *   The message to store in the log. If empty, a text that contains all useful
1919
 *   information about the passed-in exception is used.
1920
 * @param $variables
1921
 *   Array of variables to replace in the message on display. Defaults to the
1922
 *   return value of _drupal_decode_exception().
1923
 * @param $severity
1924
 *   The severity of the message, as per RFC 3164.
1925
 * @param $link
1926
 *   A link to associate with the message.
1927
 *
1928
 * @see watchdog()
1929
 * @see _drupal_decode_exception()
1930
 */
1931
function watchdog_exception($type, Exception $exception, $message = NULL, $variables = array(), $severity = WATCHDOG_ERROR, $link = NULL) {
1932

    
1933
   // Use a default value if $message is not set.
1934
   if (empty($message)) {
1935
     // The exception message is run through check_plain() by _drupal_decode_exception().
1936
     $message = '%type: !message in %function (line %line of %file).';
1937
   }
1938
   // $variables must be an array so that we can add the exception information.
1939
   if (!is_array($variables)) {
1940
     $variables = array();
1941
   }
1942

    
1943
   require_once DRUPAL_ROOT . '/includes/errors.inc';
1944
   $variables += _drupal_decode_exception($exception);
1945
   watchdog($type, $message, $variables, $severity, $link);
1946
}
1947

    
1948
/**
1949
 * Logs a system message.
1950
 *
1951
 * @param $type
1952
 *   The category to which this message belongs. Can be any string, but the
1953
 *   general practice is to use the name of the module calling watchdog().
1954
 * @param $message
1955
 *   The message to store in the log. Keep $message translatable
1956
 *   by not concatenating dynamic values into it! Variables in the
1957
 *   message should be added by using placeholder strings alongside
1958
 *   the variables argument to declare the value of the placeholders.
1959
 *   See t() for documentation on how $message and $variables interact.
1960
 * @param $variables
1961
 *   Array of variables to replace in the message on display or
1962
 *   NULL if message is already translated or not possible to
1963
 *   translate.
1964
 * @param $severity
1965
 *   The severity of the message; one of the following values as defined in
1966
 *   @link http://www.faqs.org/rfcs/rfc3164.html RFC 3164: @endlink
1967
 *   - WATCHDOG_EMERGENCY: Emergency, system is unusable.
1968
 *   - WATCHDOG_ALERT: Alert, action must be taken immediately.
1969
 *   - WATCHDOG_CRITICAL: Critical conditions.
1970
 *   - WATCHDOG_ERROR: Error conditions.
1971
 *   - WATCHDOG_WARNING: Warning conditions.
1972
 *   - WATCHDOG_NOTICE: (default) Normal but significant conditions.
1973
 *   - WATCHDOG_INFO: Informational messages.
1974
 *   - WATCHDOG_DEBUG: Debug-level messages.
1975
 * @param $link
1976
 *   A link to associate with the message.
1977
 *
1978
 * @see watchdog_severity_levels()
1979
 * @see hook_watchdog()
1980
 */
1981
function watchdog($type, $message, $variables = array(), $severity = WATCHDOG_NOTICE, $link = NULL) {
1982
  global $user, $base_root;
1983

    
1984
  static $in_error_state = FALSE;
1985

    
1986
  // It is possible that the error handling will itself trigger an error. In that case, we could
1987
  // end up in an infinite loop. To avoid that, we implement a simple static semaphore.
1988
  if (!$in_error_state && function_exists('module_implements')) {
1989
    $in_error_state = TRUE;
1990

    
1991
    // The user object may not exist in all conditions, so 0 is substituted if needed.
1992
    $user_uid = isset($user->uid) ? $user->uid : 0;
1993

    
1994
    // Prepare the fields to be logged
1995
    $log_entry = array(
1996
      'type'        => $type,
1997
      'message'     => $message,
1998
      'variables'   => $variables,
1999
      'severity'    => $severity,
2000
      'link'        => $link,
2001
      'user'        => $user,
2002
      'uid'         => $user_uid,
2003
      'request_uri' => $base_root . request_uri(),
2004
      'referer'     => isset($_SERVER['HTTP_REFERER']) ? $_SERVER['HTTP_REFERER'] : '',
2005
      'ip'          => ip_address(),
2006
      // Request time isn't accurate for long processes, use time() instead.
2007
      'timestamp'   => time(),
2008
    );
2009

    
2010
    // Call the logging hooks to log/process the message
2011
    foreach (module_implements('watchdog') as $module) {
2012
      module_invoke($module, 'watchdog', $log_entry);
2013
    }
2014

    
2015
    // It is critical that the semaphore is only cleared here, in the parent
2016
    // watchdog() call (not outside the loop), to prevent recursive execution.
2017
    $in_error_state = FALSE;
2018
  }
2019
}
2020

    
2021
/**
2022
 * Sets a message to display to the user.
2023
 *
2024
 * Messages are stored in a session variable and displayed in page.tpl.php via
2025
 * the $messages theme variable.
2026
 *
2027
 * Example usage:
2028
 * @code
2029
 * drupal_set_message(t('An error occurred and processing did not complete.'), 'error');
2030
 * @endcode
2031
 *
2032
 * @param string $message
2033
 *   (optional) The translated message to be displayed to the user. For
2034
 *   consistency with other messages, it should begin with a capital letter and
2035
 *   end with a period.
2036
 * @param string $type
2037
 *   (optional) The message's type. Defaults to 'status'. These values are
2038
 *   supported:
2039
 *   - 'status'
2040
 *   - 'warning'
2041
 *   - 'error'
2042
 * @param bool $repeat
2043
 *   (optional) If this is FALSE and the message is already set, then the
2044
 *   message won't be repeated. Defaults to TRUE.
2045
 *
2046
 * @return array|null
2047
 *   A multidimensional array with keys corresponding to the set message types.
2048
 *   The indexed array values of each contain the set messages for that type.
2049
 *   Or, if there are no messages set, the function returns NULL.
2050
 *
2051
 * @see drupal_get_messages()
2052
 * @see theme_status_messages()
2053
 */
2054
function drupal_set_message($message = NULL, $type = 'status', $repeat = TRUE) {
2055
  if ($message || $message === '0' || $message === 0) {
2056
    if (!isset($_SESSION['messages'][$type])) {
2057
      $_SESSION['messages'][$type] = array();
2058
    }
2059

    
2060
    if ($repeat || !in_array($message, $_SESSION['messages'][$type])) {
2061
      $_SESSION['messages'][$type][] = $message;
2062
    }
2063

    
2064
    // Mark this page as being uncacheable.
2065
    drupal_page_is_cacheable(FALSE);
2066
  }
2067

    
2068
  // Messages not set when DB connection fails.
2069
  return isset($_SESSION['messages']) ? $_SESSION['messages'] : NULL;
2070
}
2071

    
2072
/**
2073
 * Returns all messages that have been set with drupal_set_message().
2074
 *
2075
 * @param string $type
2076
 *   (optional) Limit the messages returned by type. Defaults to NULL, meaning
2077
 *   all types. These values are supported:
2078
 *   - NULL
2079
 *   - 'status'
2080
 *   - 'warning'
2081
 *   - 'error'
2082
 * @param bool $clear_queue
2083
 *   (optional) If this is TRUE, the queue will be cleared of messages of the
2084
 *   type specified in the $type parameter. Otherwise the queue will be left
2085
 *   intact. Defaults to TRUE.
2086
 *
2087
 * @return array
2088
 *   A multidimensional array with keys corresponding to the set message types.
2089
 *   The indexed array values of each contain the set messages for that type.
2090
 *   The messages returned are limited to the type specified in the $type
2091
 *   parameter. If there are no messages of the specified type, an empty array
2092
 *   is returned.
2093
 *
2094
 * @see drupal_set_message()
2095
 * @see theme_status_messages()
2096
 */
2097
function drupal_get_messages($type = NULL, $clear_queue = TRUE) {
2098
  if ($messages = drupal_set_message()) {
2099
    if ($type) {
2100
      if ($clear_queue) {
2101
        unset($_SESSION['messages'][$type]);
2102
      }
2103
      if (isset($messages[$type])) {
2104
        return array($type => $messages[$type]);
2105
      }
2106
    }
2107
    else {
2108
      if ($clear_queue) {
2109
        unset($_SESSION['messages']);
2110
      }
2111
      return $messages;
2112
    }
2113
  }
2114
  return array();
2115
}
2116

    
2117
/**
2118
 * Gets the title of the current page.
2119
 *
2120
 * The title is displayed on the page and in the title bar.
2121
 *
2122
 * @return
2123
 *   The current page's title.
2124
 */
2125
function drupal_get_title() {
2126
  $title = drupal_set_title();
2127

    
2128
  // During a bootstrap, menu.inc is not included and thus we cannot provide a title.
2129
  if (!isset($title) && function_exists('menu_get_active_title')) {
2130
    $title = check_plain(menu_get_active_title());
2131
  }
2132

    
2133
  return $title;
2134
}
2135

    
2136
/**
2137
 * Sets the title of the current page.
2138
 *
2139
 * The title is displayed on the page and in the title bar.
2140
 *
2141
 * @param $title
2142
 *   Optional string value to assign to the page title; or if set to NULL
2143
 *   (default), leaves the current title unchanged.
2144
 * @param $output
2145
 *   Optional flag - normally should be left as CHECK_PLAIN. Only set to
2146
 *   PASS_THROUGH if you have already removed any possibly dangerous code
2147
 *   from $title using a function like check_plain() or filter_xss(). With this
2148
 *   flag the string will be passed through unchanged.
2149
 *
2150
 * @return
2151
 *   The updated title of the current page.
2152
 */
2153
function drupal_set_title($title = NULL, $output = CHECK_PLAIN) {
2154
  $stored_title = &drupal_static(__FUNCTION__);
2155

    
2156
  if (isset($title)) {
2157
    $stored_title = ($output == PASS_THROUGH) ? $title : check_plain($title);
2158
  }
2159

    
2160
  return $stored_title;
2161
}
2162

    
2163
/**
2164
 * Checks to see if an IP address has been blocked.
2165
 *
2166
 * Blocked IP addresses are stored in the database by default. However for
2167
 * performance reasons we allow an override in settings.php. This allows us
2168
 * to avoid querying the database at this critical stage of the bootstrap if
2169
 * an administrative interface for IP address blocking is not required.
2170
 *
2171
 * @param $ip
2172
 *   IP address to check.
2173
 *
2174
 * @return bool
2175
 *   TRUE if access is denied, FALSE if access is allowed.
2176
 */
2177
function drupal_is_denied($ip) {
2178
  // Because this function is called on every page request, we first check
2179
  // for an array of IP addresses in settings.php before querying the
2180
  // database.
2181
  $blocked_ips = variable_get('blocked_ips');
2182
  $denied = FALSE;
2183
  if (isset($blocked_ips) && is_array($blocked_ips)) {
2184
    $denied = in_array($ip, $blocked_ips);
2185
  }
2186
  // Only check if database.inc is loaded already. If
2187
  // $conf['page_cache_without_database'] = TRUE; is set in settings.php,
2188
  // then the database won't be loaded here so the IPs in the database
2189
  // won't be denied. However the user asked explicitly not to use the
2190
  // database and also in this case it's quite likely that the user relies
2191
  // on higher performance solutions like a firewall.
2192
  elseif (class_exists('Database', FALSE)) {
2193
    $denied = (bool)db_query("SELECT 1 FROM {blocked_ips} WHERE ip = :ip", array(':ip' => $ip))->fetchField();
2194
  }
2195
  return $denied;
2196
}
2197

    
2198
/**
2199
 * Handles denied users.
2200
 *
2201
 * @param $ip
2202
 *   IP address to check. Prints a message and exits if access is denied.
2203
 */
2204
function drupal_block_denied($ip) {
2205
  // Deny access to blocked IP addresses - t() is not yet available.
2206
  if (drupal_is_denied($ip)) {
2207
    header($_SERVER['SERVER_PROTOCOL'] . ' 403 Forbidden');
2208
    print 'Sorry, ' . check_plain(ip_address()) . ' has been banned.';
2209
    exit();
2210
  }
2211
}
2212

    
2213
/**
2214
 * Returns a URL-safe, base64 encoded string of highly randomized bytes (over the full 8-bit range).
2215
 *
2216
 * @param $byte_count
2217
 *   The number of random bytes to fetch and base64 encode.
2218
 *
2219
 * @return string
2220
 *   The base64 encoded result will have a length of up to 4 * $byte_count.
2221
 */
2222
function drupal_random_key($byte_count = 32) {
2223
  return drupal_base64_encode(drupal_random_bytes($byte_count));
2224
}
2225

    
2226
/**
2227
 * Returns a URL-safe, base64 encoded version of the supplied string.
2228
 *
2229
 * @param $string
2230
 *   The string to convert to base64.
2231
 *
2232
 * @return string
2233
 */
2234
function drupal_base64_encode($string) {
2235
  $data = base64_encode($string);
2236
  // Modify the output so it's safe to use in URLs.
2237
  return strtr($data, array('+' => '-', '/' => '_', '=' => ''));
2238
}
2239

    
2240
/**
2241
 * Returns a string of highly randomized bytes (over the full 8-bit range).
2242
 *
2243
 * This function is better than simply calling mt_rand() or any other built-in
2244
 * PHP function because it can return a long string of bytes (compared to < 4
2245
 * bytes normally from mt_rand()) and uses the best available pseudo-random
2246
 * source.
2247
 *
2248
 * @param $count
2249
 *   The number of characters (bytes) to return in the string.
2250
 */
2251
function drupal_random_bytes($count)  {
2252
  // $random_state does not use drupal_static as it stores random bytes.
2253
  static $random_state, $bytes, $has_openssl;
2254

    
2255
  $missing_bytes = $count - strlen($bytes);
2256

    
2257
  if ($missing_bytes > 0) {
2258
    // PHP versions prior 5.3.4 experienced openssl_random_pseudo_bytes()
2259
    // locking on Windows and rendered it unusable.
2260
    if (!isset($has_openssl)) {
2261
      $has_openssl = version_compare(PHP_VERSION, '5.3.4', '>=') && function_exists('openssl_random_pseudo_bytes');
2262
    }
2263

    
2264
    // openssl_random_pseudo_bytes() will find entropy in a system-dependent
2265
    // way.
2266
    if ($has_openssl) {
2267
      $bytes .= openssl_random_pseudo_bytes($missing_bytes);
2268
    }
2269

    
2270
    // Else, read directly from /dev/urandom, which is available on many *nix
2271
    // systems and is considered cryptographically secure.
2272
    elseif ($fh = @fopen('/dev/urandom', 'rb')) {
2273
      // PHP only performs buffered reads, so in reality it will always read
2274
      // at least 4096 bytes. Thus, it costs nothing extra to read and store
2275
      // that much so as to speed any additional invocations.
2276
      $bytes .= fread($fh, max(4096, $missing_bytes));
2277
      fclose($fh);
2278
    }
2279

    
2280
    // If we couldn't get enough entropy, this simple hash-based PRNG will
2281
    // generate a good set of pseudo-random bytes on any system.
2282
    // Note that it may be important that our $random_state is passed
2283
    // through hash() prior to being rolled into $output, that the two hash()
2284
    // invocations are different, and that the extra input into the first one -
2285
    // the microtime() - is prepended rather than appended. This is to avoid
2286
    // directly leaking $random_state via the $output stream, which could
2287
    // allow for trivial prediction of further "random" numbers.
2288
    if (strlen($bytes) < $count) {
2289
      // Initialize on the first call. The contents of $_SERVER includes a mix of
2290
      // user-specific and system information that varies a little with each page.
2291
      if (!isset($random_state)) {
2292
        $random_state = print_r($_SERVER, TRUE);
2293
        if (function_exists('getmypid')) {
2294
          // Further initialize with the somewhat random PHP process ID.
2295
          $random_state .= getmypid();
2296
        }
2297
        $bytes = '';
2298
      }
2299

    
2300
      do {
2301
        $random_state = hash('sha256', microtime() . mt_rand() . $random_state);
2302
        $bytes .= hash('sha256', mt_rand() . $random_state, TRUE);
2303
      }
2304
      while (strlen($bytes) < $count);
2305
    }
2306
  }
2307
  $output = substr($bytes, 0, $count);
2308
  $bytes = substr($bytes, $count);
2309
  return $output;
2310
}
2311

    
2312
/**
2313
 * Calculates a base-64 encoded, URL-safe sha-256 hmac.
2314
 *
2315
 * @param string $data
2316
 *   String to be validated with the hmac.
2317
 * @param string $key
2318
 *   A secret string key.
2319
 *
2320
 * @return string
2321
 *   A base-64 encoded sha-256 hmac, with + replaced with -, / with _ and
2322
 *   any = padding characters removed.
2323
 */
2324
function drupal_hmac_base64($data, $key) {
2325
  // Casting $data and $key to strings here is necessary to avoid empty string
2326
  // results of the hash function if they are not scalar values. As this
2327
  // function is used in security-critical contexts like token validation it is
2328
  // important that it never returns an empty string.
2329
  $hmac = base64_encode(hash_hmac('sha256', (string) $data, (string) $key, TRUE));
2330
  // Modify the hmac so it's safe to use in URLs.
2331
  return strtr($hmac, array('+' => '-', '/' => '_', '=' => ''));
2332
}
2333

    
2334
/**
2335
 * Calculates a base-64 encoded, URL-safe sha-256 hash.
2336
 *
2337
 * @param $data
2338
 *   String to be hashed.
2339
 *
2340
 * @return
2341
 *   A base-64 encoded sha-256 hash, with + replaced with -, / with _ and
2342
 *   any = padding characters removed.
2343
 */
2344
function drupal_hash_base64($data) {
2345
  $hash = base64_encode(hash('sha256', $data, TRUE));
2346
  // Modify the hash so it's safe to use in URLs.
2347
  return strtr($hash, array('+' => '-', '/' => '_', '=' => ''));
2348
}
2349

    
2350
/**
2351
 * Merges multiple arrays, recursively, and returns the merged array.
2352
 *
2353
 * This function is similar to PHP's array_merge_recursive() function, but it
2354
 * handles non-array values differently. When merging values that are not both
2355
 * arrays, the latter value replaces the former rather than merging with it.
2356
 *
2357
 * Example:
2358
 * @code
2359
 * $link_options_1 = array('fragment' => 'x', 'attributes' => array('title' => t('X'), 'class' => array('a', 'b')));
2360
 * $link_options_2 = array('fragment' => 'y', 'attributes' => array('title' => t('Y'), 'class' => array('c', 'd')));
2361
 *
2362
 * // This results in array('fragment' => array('x', 'y'), 'attributes' => array('title' => array(t('X'), t('Y')), 'class' => array('a', 'b', 'c', 'd'))).
2363
 * $incorrect = array_merge_recursive($link_options_1, $link_options_2);
2364
 *
2365
 * // This results in array('fragment' => 'y', 'attributes' => array('title' => t('Y'), 'class' => array('a', 'b', 'c', 'd'))).
2366
 * $correct = drupal_array_merge_deep($link_options_1, $link_options_2);
2367
 * @endcode
2368
 *
2369
 * @param ...
2370
 *   Arrays to merge.
2371
 *
2372
 * @return
2373
 *   The merged array.
2374
 *
2375
 * @see drupal_array_merge_deep_array()
2376
 */
2377
function drupal_array_merge_deep() {
2378
  $args = func_get_args();
2379
  return drupal_array_merge_deep_array($args);
2380
}
2381

    
2382
/**
2383
 * Merges multiple arrays, recursively, and returns the merged array.
2384
 *
2385
 * This function is equivalent to drupal_array_merge_deep(), except the
2386
 * input arrays are passed as a single array parameter rather than a variable
2387
 * parameter list.
2388
 *
2389
 * The following are equivalent:
2390
 * - drupal_array_merge_deep($a, $b);
2391
 * - drupal_array_merge_deep_array(array($a, $b));
2392
 *
2393
 * The following are also equivalent:
2394
 * - call_user_func_array('drupal_array_merge_deep', $arrays_to_merge);
2395
 * - drupal_array_merge_deep_array($arrays_to_merge);
2396
 *
2397
 * @see drupal_array_merge_deep()
2398
 */
2399
function drupal_array_merge_deep_array($arrays) {
2400
  $result = array();
2401

    
2402
  foreach ($arrays as $array) {
2403
    foreach ($array as $key => $value) {
2404
      // Renumber integer keys as array_merge_recursive() does. Note that PHP
2405
      // automatically converts array keys that are integer strings (e.g., '1')
2406
      // to integers.
2407
      if (is_integer($key)) {
2408
        $result[] = $value;
2409
      }
2410
      // Recurse when both values are arrays.
2411
      elseif (isset($result[$key]) && is_array($result[$key]) && is_array($value)) {
2412
        $result[$key] = drupal_array_merge_deep_array(array($result[$key], $value));
2413
      }
2414
      // Otherwise, use the latter value, overriding any previous value.
2415
      else {
2416
        $result[$key] = $value;
2417
      }
2418
    }
2419
  }
2420

    
2421
  return $result;
2422
}
2423

    
2424
/**
2425
 * Generates a default anonymous $user object.
2426
 *
2427
 * @return Object - the user object.
2428
 */
2429
function drupal_anonymous_user() {
2430
  $user = variable_get('drupal_anonymous_user_object', new stdClass);
2431
  $user->uid = 0;
2432
  $user->hostname = ip_address();
2433
  $user->roles = array();
2434
  $user->roles[DRUPAL_ANONYMOUS_RID] = 'anonymous user';
2435
  $user->cache = 0;
2436
  return $user;
2437
}
2438

    
2439
/**
2440
 * Ensures Drupal is bootstrapped to the specified phase.
2441
 *
2442
 * In order to bootstrap Drupal from another PHP script, you can use this code:
2443
 * @code
2444
 *   define('DRUPAL_ROOT', '/path/to/drupal');
2445
 *   require_once DRUPAL_ROOT . '/includes/bootstrap.inc';
2446
 *   drupal_bootstrap(DRUPAL_BOOTSTRAP_FULL);
2447
 * @endcode
2448
 *
2449
 * @param int $phase
2450
 *   A constant telling which phase to bootstrap to. When you bootstrap to a
2451
 *   particular phase, all earlier phases are run automatically. Possible
2452
 *   values:
2453
 *   - DRUPAL_BOOTSTRAP_CONFIGURATION: Initializes configuration.
2454
 *   - DRUPAL_BOOTSTRAP_PAGE_CACHE: Tries to serve a cached page.
2455
 *   - DRUPAL_BOOTSTRAP_DATABASE: Initializes the database layer.
2456
 *   - DRUPAL_BOOTSTRAP_VARIABLES: Initializes the variable system.
2457
 *   - DRUPAL_BOOTSTRAP_SESSION: Initializes session handling.
2458
 *   - DRUPAL_BOOTSTRAP_PAGE_HEADER: Sets up the page header.
2459
 *   - DRUPAL_BOOTSTRAP_LANGUAGE: Finds out the language of the page.
2460
 *   - DRUPAL_BOOTSTRAP_FULL: Fully loads Drupal. Validates and fixes input
2461
 *     data.
2462
 * @param boolean $new_phase
2463
 *   A boolean, set to FALSE if calling drupal_bootstrap from inside a
2464
 *   function called from drupal_bootstrap (recursion).
2465
 *
2466
 * @return int
2467
 *   The most recently completed phase.
2468
 */
2469
function drupal_bootstrap($phase = NULL, $new_phase = TRUE) {
2470
  // Not drupal_static(), because does not depend on any run-time information.
2471
  static $phases = array(
2472
    DRUPAL_BOOTSTRAP_CONFIGURATION,
2473
    DRUPAL_BOOTSTRAP_PAGE_CACHE,
2474
    DRUPAL_BOOTSTRAP_DATABASE,
2475
    DRUPAL_BOOTSTRAP_VARIABLES,
2476
    DRUPAL_BOOTSTRAP_SESSION,
2477
    DRUPAL_BOOTSTRAP_PAGE_HEADER,
2478
    DRUPAL_BOOTSTRAP_LANGUAGE,
2479
    DRUPAL_BOOTSTRAP_FULL,
2480
  );
2481
  // Not drupal_static(), because the only legitimate API to control this is to
2482
  // call drupal_bootstrap() with a new phase parameter.
2483
  static $final_phase;
2484
  // Not drupal_static(), because it's impossible to roll back to an earlier
2485
  // bootstrap state.
2486
  static $stored_phase = -1;
2487

    
2488
  if (isset($phase)) {
2489
    // When not recursing, store the phase name so it's not forgotten while
2490
    // recursing but take care of not going backwards.
2491
    if ($new_phase && $phase >= $stored_phase) {
2492
      $final_phase = $phase;
2493
    }
2494

    
2495
    // Call a phase if it has not been called before and is below the requested
2496
    // phase.
2497
    while ($phases && $phase > $stored_phase && $final_phase > $stored_phase) {
2498
      $current_phase = array_shift($phases);
2499

    
2500
      // This function is re-entrant. Only update the completed phase when the
2501
      // current call actually resulted in a progress in the bootstrap process.
2502
      if ($current_phase > $stored_phase) {
2503
        $stored_phase = $current_phase;
2504
      }
2505

    
2506
      switch ($current_phase) {
2507
        case DRUPAL_BOOTSTRAP_CONFIGURATION:
2508
          _drupal_bootstrap_configuration();
2509
          break;
2510

    
2511
        case DRUPAL_BOOTSTRAP_PAGE_CACHE:
2512
          _drupal_bootstrap_page_cache();
2513
          break;
2514

    
2515
        case DRUPAL_BOOTSTRAP_DATABASE:
2516
          _drupal_bootstrap_database();
2517
          break;
2518

    
2519
        case DRUPAL_BOOTSTRAP_VARIABLES:
2520
          _drupal_bootstrap_variables();
2521
          break;
2522

    
2523
        case DRUPAL_BOOTSTRAP_SESSION:
2524
          require_once DRUPAL_ROOT . '/' . variable_get('session_inc', 'includes/session.inc');
2525
          drupal_session_initialize();
2526
          break;
2527

    
2528
        case DRUPAL_BOOTSTRAP_PAGE_HEADER:
2529
          _drupal_bootstrap_page_header();
2530
          break;
2531

    
2532
        case DRUPAL_BOOTSTRAP_LANGUAGE:
2533
          drupal_language_initialize();
2534
          break;
2535

    
2536
        case DRUPAL_BOOTSTRAP_FULL:
2537
          require_once DRUPAL_ROOT . '/includes/common.inc';
2538
          _drupal_bootstrap_full();
2539
          break;
2540
      }
2541
    }
2542
  }
2543
  return $stored_phase;
2544
}
2545

    
2546
/**
2547
 * Returns the time zone of the current user.
2548
 */
2549
function drupal_get_user_timezone() {
2550
  global $user;
2551
  if (variable_get('configurable_timezones', 1) && $user->uid && $user->timezone) {
2552
    return $user->timezone;
2553
  }
2554
  else {
2555
    // Ignore PHP strict notice if time zone has not yet been set in the php.ini
2556
    // configuration.
2557
    return variable_get('date_default_timezone', @date_default_timezone_get());
2558
  }
2559
}
2560

    
2561
/**
2562
 * Gets a salt useful for hardening against SQL injection.
2563
 *
2564
 * @return
2565
 *   A salt based on information in settings.php, not in the database.
2566
 */
2567
function drupal_get_hash_salt() {
2568
  global $drupal_hash_salt, $databases;
2569
  // If the $drupal_hash_salt variable is empty, a hash of the serialized
2570
  // database credentials is used as a fallback salt.
2571
  return empty($drupal_hash_salt) ? hash('sha256', serialize($databases)) : $drupal_hash_salt;
2572
}
2573

    
2574
/**
2575
 * Provides custom PHP error handling.
2576
 *
2577
 * @param $error_level
2578
 *   The level of the error raised.
2579
 * @param $message
2580
 *   The error message.
2581
 * @param $filename
2582
 *   The filename that the error was raised in.
2583
 * @param $line
2584
 *   The line number the error was raised at.
2585
 * @param $context
2586
 *   An array that points to the active symbol table at the point the error
2587
 *   occurred.
2588
 */
2589
function _drupal_error_handler($error_level, $message, $filename, $line, $context) {
2590
  require_once DRUPAL_ROOT . '/includes/errors.inc';
2591
  _drupal_error_handler_real($error_level, $message, $filename, $line, $context);
2592
}
2593

    
2594
/**
2595
 * Provides custom PHP exception handling.
2596
 *
2597
 * Uncaught exceptions are those not enclosed in a try/catch block. They are
2598
 * always fatal: the execution of the script will stop as soon as the exception
2599
 * handler exits.
2600
 *
2601
 * @param $exception
2602
 *   The exception object that was thrown.
2603
 */
2604
function _drupal_exception_handler($exception) {
2605
  require_once DRUPAL_ROOT . '/includes/errors.inc';
2606

    
2607
  try {
2608
    // Log the message to the watchdog and return an error page to the user.
2609
    _drupal_log_error(_drupal_decode_exception($exception), TRUE);
2610
  }
2611
  catch (Exception $exception2) {
2612
    // Another uncaught exception was thrown while handling the first one.
2613
    // If we are displaying errors, then do so with no possibility of a further uncaught exception being thrown.
2614
    if (error_displayable()) {
2615
      print '<h1>Additional uncaught exception thrown while handling exception.</h1>';
2616
      print '<h2>Original</h2><p>' . _drupal_render_exception_safe($exception) . '</p>';
2617
      print '<h2>Additional</h2><p>' . _drupal_render_exception_safe($exception2) . '</p><hr />';
2618
    }
2619
  }
2620
}
2621

    
2622
/**
2623
 * Sets up the script environment and loads settings.php.
2624
 */
2625
function _drupal_bootstrap_configuration() {
2626
  // Set the Drupal custom error handler.
2627
  set_error_handler('_drupal_error_handler');
2628
  set_exception_handler('_drupal_exception_handler');
2629

    
2630
  drupal_environment_initialize();
2631
  // Start a page timer:
2632
  timer_start('page');
2633
  // Initialize the configuration, including variables from settings.php.
2634
  drupal_settings_initialize();
2635

    
2636
  // Sanitize unsafe keys from the request.
2637
  require_once DRUPAL_ROOT . '/includes/request-sanitizer.inc';
2638
  DrupalRequestSanitizer::sanitize();
2639
}
2640

    
2641
/**
2642
 * Attempts to serve a page from the cache.
2643
 */
2644
function _drupal_bootstrap_page_cache() {
2645
  global $user;
2646

    
2647
  // Allow specifying special cache handlers in settings.php, like
2648
  // using memcached or files for storing cache information.
2649
  require_once DRUPAL_ROOT . '/includes/cache.inc';
2650
  foreach (variable_get('cache_backends', array()) as $include) {
2651
    require_once DRUPAL_ROOT . '/' . $include;
2652
  }
2653
  // Check for a cache mode force from settings.php.
2654
  if (variable_get('page_cache_without_database')) {
2655
    $cache_enabled = TRUE;
2656
  }
2657
  else {
2658
    drupal_bootstrap(DRUPAL_BOOTSTRAP_VARIABLES, FALSE);
2659
    $cache_enabled = variable_get('cache');
2660
  }
2661
  drupal_block_denied(ip_address());
2662
  // If there is no session cookie and cache is enabled (or forced), try
2663
  // to serve a cached page.
2664
  if (!isset($_COOKIE[session_name()]) && $cache_enabled) {
2665
    // Make sure there is a user object because its timestamp will be
2666
    // checked, hook_boot might check for anonymous user etc.
2667
    $user = drupal_anonymous_user();
2668
    // Get the page from the cache.
2669
    $cache = drupal_page_get_cache();
2670
    // If there is a cached page, display it.
2671
    if (is_object($cache)) {
2672
      header('X-Drupal-Cache: HIT');
2673
      // Restore the metadata cached with the page.
2674
      $_GET['q'] = $cache->data['path'];
2675
      drupal_set_title($cache->data['title'], PASS_THROUGH);
2676
      date_default_timezone_set(drupal_get_user_timezone());
2677
      // If the skipping of the bootstrap hooks is not enforced, call
2678
      // hook_boot.
2679
      if (variable_get('page_cache_invoke_hooks', TRUE)) {
2680
        bootstrap_invoke_all('boot');
2681
      }
2682
      drupal_serve_page_from_cache($cache);
2683
      // If the skipping of the bootstrap hooks is not enforced, call
2684
      // hook_exit.
2685
      if (variable_get('page_cache_invoke_hooks', TRUE)) {
2686
        bootstrap_invoke_all('exit');
2687
      }
2688
      // We are done.
2689
      exit;
2690
    }
2691
    else {
2692
      header('X-Drupal-Cache: MISS');
2693
    }
2694
  }
2695
}
2696

    
2697
/**
2698
 * Initializes the database system and registers autoload functions.
2699
 */
2700
function _drupal_bootstrap_database() {
2701
  // Redirect the user to the installation script if Drupal has not been
2702
  // installed yet (i.e., if no $databases array has been defined in the
2703
  // settings.php file) and we are not already installing.
2704
  if (empty($GLOBALS['databases']) && !drupal_installation_attempted()) {
2705
    include_once DRUPAL_ROOT . '/includes/install.inc';
2706
    install_goto('install.php');
2707
  }
2708

    
2709
  // The user agent header is used to pass a database prefix in the request when
2710
  // running tests. However, for security reasons, it is imperative that we
2711
  // validate we ourselves made the request.
2712
  if ($test_prefix = drupal_valid_test_ua()) {
2713
    // Set the test run id for use in other parts of Drupal.
2714
    $test_info = &$GLOBALS['drupal_test_info'];
2715
    $test_info['test_run_id'] = $test_prefix;
2716
    $test_info['in_child_site'] = TRUE;
2717

    
2718
    foreach ($GLOBALS['databases']['default'] as &$value) {
2719
      // Extract the current default database prefix.
2720
      if (!isset($value['prefix'])) {
2721
        $current_prefix = '';
2722
      }
2723
      elseif (is_array($value['prefix'])) {
2724
        $current_prefix = $value['prefix']['default'];
2725
      }
2726
      else {
2727
        $current_prefix = $value['prefix'];
2728
      }
2729

    
2730
      // Remove the current database prefix and replace it by our own.
2731
      $value['prefix'] = array(
2732
        'default' => $current_prefix . $test_prefix,
2733
      );
2734
    }
2735
  }
2736

    
2737
  // Initialize the database system. Note that the connection
2738
  // won't be initialized until it is actually requested.
2739
  require_once DRUPAL_ROOT . '/includes/database/database.inc';
2740

    
2741
  // Register autoload functions so that we can access classes and interfaces.
2742
  // The database autoload routine comes first so that we can load the database
2743
  // system without hitting the database. That is especially important during
2744
  // the install or upgrade process.
2745
  spl_autoload_register('drupal_autoload_class');
2746
  spl_autoload_register('drupal_autoload_interface');
2747
  if (version_compare(PHP_VERSION, '5.4') >= 0) {
2748
    spl_autoload_register('drupal_autoload_trait');
2749
  }
2750
}
2751

    
2752
/**
2753
 * Loads system variables and all enabled bootstrap modules.
2754
 */
2755
function _drupal_bootstrap_variables() {
2756
  global $conf;
2757

    
2758
  // Initialize the lock system.
2759
  require_once DRUPAL_ROOT . '/' . variable_get('lock_inc', 'includes/lock.inc');
2760
  lock_initialize();
2761

    
2762
  // Load variables from the database, but do not overwrite variables set in settings.php.
2763
  $conf = variable_initialize(isset($conf) ? $conf : array());
2764
  // Load bootstrap modules.
2765
  require_once DRUPAL_ROOT . '/includes/module.inc';
2766
  module_load_all(TRUE);
2767

    
2768
  // Sanitize the destination parameter (which is often used for redirects) to
2769
  // prevent open redirect attacks leading to other domains. Sanitize both
2770
  // $_GET['destination'] and $_REQUEST['destination'] to protect code that
2771
  // relies on either, but do not sanitize $_POST to avoid interfering with
2772
  // unrelated form submissions. The sanitization happens here because
2773
  // url_is_external() requires the variable system to be available.
2774
  if (isset($_GET['destination']) || isset($_REQUEST['destination'])) {
2775
    require_once DRUPAL_ROOT . '/includes/common.inc';
2776
    // If the destination is an external URL, remove it.
2777
    if (isset($_GET['destination']) && url_is_external($_GET['destination'])) {
2778
      unset($_GET['destination']);
2779
      unset($_REQUEST['destination']);
2780
    }
2781
    // Use the DrupalRequestSanitizer to ensure that the destination's query
2782
    // parameters are not dangerous.
2783
    if (isset($_GET['destination'])) {
2784
      DrupalRequestSanitizer::cleanDestination();
2785
    }
2786
    // If there's still something in $_REQUEST['destination'] that didn't come
2787
    // from $_GET, check it too.
2788
    if (isset($_REQUEST['destination']) && (!isset($_GET['destination']) || $_REQUEST['destination'] != $_GET['destination']) && url_is_external($_REQUEST['destination'])) {
2789
      unset($_REQUEST['destination']);
2790
    }
2791
  }
2792
}
2793

    
2794
/**
2795
 * Invokes hook_boot(), initializes locking system, and sends HTTP headers.
2796
 */
2797
function _drupal_bootstrap_page_header() {
2798
  bootstrap_invoke_all('boot');
2799

    
2800
  if (!drupal_is_cli()) {
2801
    ob_start();
2802
    drupal_page_header();
2803
  }
2804
}
2805

    
2806
/**
2807
 * Returns the current bootstrap phase for this Drupal process.
2808
 *
2809
 * The current phase is the one most recently completed by drupal_bootstrap().
2810
 *
2811
 * @see drupal_bootstrap()
2812
 */
2813
function drupal_get_bootstrap_phase() {
2814
  return drupal_bootstrap(NULL, FALSE);
2815
}
2816

    
2817
/**
2818
 * Returns the test prefix if this is an internal request from SimpleTest.
2819
 *
2820
 * @return
2821
 *   Either the simpletest prefix (the string "simpletest" followed by any
2822
 *   number of digits) or FALSE if the user agent does not contain a valid
2823
 *   HMAC and timestamp.
2824
 */
2825
function drupal_valid_test_ua() {
2826
  // No reason to reset this.
2827
  static $test_prefix;
2828

    
2829
  if (isset($test_prefix)) {
2830
    return $test_prefix;
2831
  }
2832

    
2833
  if (isset($_SERVER['HTTP_USER_AGENT']) && preg_match("/^(simpletest\d+);(.+);(.+);(.+)$/", $_SERVER['HTTP_USER_AGENT'], $matches)) {
2834
    list(, $prefix, $time, $salt, $hmac) = $matches;
2835
    $check_string =  $prefix . ';' . $time . ';' . $salt;
2836
    // We use the salt from settings.php to make the HMAC key, since
2837
    // the database is not yet initialized and we can't access any Drupal variables.
2838
    // The file properties add more entropy not easily accessible to others.
2839
    $key = drupal_get_hash_salt() . filectime(__FILE__) . fileinode(__FILE__);
2840
    $time_diff = REQUEST_TIME - $time;
2841
    // Since we are making a local request a 5 second time window is allowed,
2842
    // and the HMAC must match.
2843
    if ($time_diff >= 0 && $time_diff <= 5 && $hmac == drupal_hmac_base64($check_string, $key)) {
2844
      $test_prefix = $prefix;
2845
      return $test_prefix;
2846
    }
2847
  }
2848

    
2849
  $test_prefix = FALSE;
2850
  return $test_prefix;
2851
}
2852

    
2853
/**
2854
 * Generates a user agent string with a HMAC and timestamp for simpletest.
2855
 */
2856
function drupal_generate_test_ua($prefix) {
2857
  static $key;
2858

    
2859
  if (!isset($key)) {
2860
    // We use the salt from settings.php to make the HMAC key, since
2861
    // the database is not yet initialized and we can't access any Drupal variables.
2862
    // The file properties add more entropy not easily accessible to others.
2863
    $key = drupal_get_hash_salt() . filectime(__FILE__) . fileinode(__FILE__);
2864
  }
2865
  // Generate a moderately secure HMAC based on the database credentials.
2866
  $salt = uniqid('', TRUE);
2867
  $check_string = $prefix . ';' . time() . ';' . $salt;
2868
  return $check_string . ';' . drupal_hmac_base64($check_string, $key);
2869
}
2870

    
2871
/**
2872
 * Enables use of the theme system without requiring database access.
2873
 *
2874
 * Loads and initializes the theme system for site installs, updates and when
2875
 * the site is in maintenance mode. This also applies when the database fails.
2876
 *
2877
 * @see _drupal_maintenance_theme()
2878
 */
2879
function drupal_maintenance_theme() {
2880
  require_once DRUPAL_ROOT . '/includes/theme.maintenance.inc';
2881
  _drupal_maintenance_theme();
2882
}
2883

    
2884
/**
2885
 * Returns a simple 404 Not Found page.
2886
 *
2887
 * If fast 404 pages are enabled, and this is a matching page then print a
2888
 * simple 404 page and exit.
2889
 *
2890
 * This function is called from drupal_deliver_html_page() at the time when a
2891
 * a normal 404 page is generated, but it can also optionally be called directly
2892
 * from settings.php to prevent a Drupal bootstrap on these pages. See
2893
 * documentation in settings.php for the benefits and drawbacks of using this.
2894
 *
2895
 * Paths to dynamically-generated content, such as image styles, should also be
2896
 * accounted for in this function.
2897
 */
2898
function drupal_fast_404() {
2899
  $exclude_paths = variable_get('404_fast_paths_exclude', FALSE);
2900
  if ($exclude_paths && !preg_match($exclude_paths, $_GET['q'])) {
2901
    $fast_paths = variable_get('404_fast_paths', FALSE);
2902
    if ($fast_paths && preg_match($fast_paths, $_GET['q'])) {
2903
      drupal_add_http_header('Status', '404 Not Found');
2904
      $fast_404_html = variable_get('404_fast_html', '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>');
2905
      // Replace @path in the variable with the page path.
2906
      print strtr($fast_404_html, array('@path' => check_plain(request_uri())));
2907
      exit;
2908
    }
2909
  }
2910
}
2911

    
2912
/**
2913
 * Returns TRUE if a Drupal installation is currently being attempted.
2914
 */
2915
function drupal_installation_attempted() {
2916
  return defined('MAINTENANCE_MODE') && MAINTENANCE_MODE == 'install';
2917
}
2918

    
2919
/**
2920
 * Returns the name of the proper localization function.
2921
 *
2922
 * get_t() exists to support localization for code that might run during
2923
 * the installation phase, when some elements of the system might not have
2924
 * loaded.
2925
 *
2926
 * This would include implementations of hook_install(), which could run
2927
 * during the Drupal installation phase, and might also be run during
2928
 * non-installation time, such as while installing the module from the
2929
 * module administration page.
2930
 *
2931
 * Example usage:
2932
 * @code
2933
 *   $t = get_t();
2934
 *   $translated = $t('translate this');
2935
 * @endcode
2936
 *
2937
 * Use t() if your code will never run during the Drupal installation phase.
2938
 * Use st() if your code will only run during installation and never any other
2939
 * time. Use get_t() if your code could run in either circumstance.
2940
 *
2941
 * @see t()
2942
 * @see st()
2943
 * @ingroup sanitization
2944
 */
2945
function get_t() {
2946
  static $t;
2947
  // This is not converted to drupal_static because there is no point in
2948
  // resetting this as it can not change in the course of a request.
2949
  if (!isset($t)) {
2950
    $t = drupal_installation_attempted() ? 'st' : 't';
2951
  }
2952
  return $t;
2953
}
2954

    
2955
/**
2956
 * Initializes all the defined language types.
2957
 */
2958
function drupal_language_initialize() {
2959
  $types = language_types();
2960

    
2961
  // Ensure the language is correctly returned, even without multilanguage
2962
  // support. Also make sure we have a $language fallback, in case a language
2963
  // negotiation callback needs to do a full bootstrap.
2964
  // Useful for eg. XML/HTML 'lang' attributes.
2965
  $default = language_default();
2966
  foreach ($types as $type) {
2967
    $GLOBALS[$type] = $default;
2968
  }
2969
  if (drupal_multilingual()) {
2970
    include_once DRUPAL_ROOT . '/includes/language.inc';
2971
    foreach ($types as $type) {
2972
      $GLOBALS[$type] = language_initialize($type);
2973
    }
2974
    // Allow modules to react on language system initialization in multilingual
2975
    // environments.
2976
    bootstrap_invoke_all('language_init');
2977
  }
2978
}
2979

    
2980
/**
2981
 * Returns a list of the built-in language types.
2982
 *
2983
 * @return
2984
 *   An array of key-values pairs where the key is the language type and the
2985
 *   value is its configurability.
2986
 */
2987
function drupal_language_types() {
2988
  return array(
2989
    LANGUAGE_TYPE_INTERFACE => TRUE,
2990
    LANGUAGE_TYPE_CONTENT => FALSE,
2991
    LANGUAGE_TYPE_URL => FALSE,
2992
  );
2993
}
2994

    
2995
/**
2996
 * Returns TRUE if there is more than one language enabled.
2997
 *
2998
 * @return
2999
 *   TRUE if more than one language is enabled.
3000
 */
3001
function drupal_multilingual() {
3002
  // The "language_count" variable stores the number of enabled languages to
3003
  // avoid unnecessarily querying the database when building the list of
3004
  // enabled languages on monolingual sites.
3005
  return variable_get('language_count', 1) > 1;
3006
}
3007

    
3008
/**
3009
 * Returns an array of the available language types.
3010
 *
3011
 * @return
3012
 *   An array of all language types where the keys of each are the language type
3013
 *   name and its value is its configurability (TRUE/FALSE).
3014
 */
3015
function language_types() {
3016
  return array_keys(variable_get('language_types', drupal_language_types()));
3017
}
3018

    
3019
/**
3020
 * Returns a list of installed languages, indexed by the specified key.
3021
 *
3022
 * @param $field
3023
 *   (optional) The field to index the list with.
3024
 *
3025
 * @return
3026
 *   An associative array, keyed on the values of $field.
3027
 *   - If $field is 'weight' or 'enabled', the array is nested, with the outer
3028
 *     array's values each being associative arrays with language codes as
3029
 *     keys and language objects as values.
3030
 *   - For all other values of $field, the array is only one level deep, and
3031
 *     the array's values are language objects.
3032
 */
3033
function language_list($field = 'language') {
3034
  $languages = &drupal_static(__FUNCTION__);
3035
  // Init language list
3036
  if (!isset($languages)) {
3037
    if (drupal_multilingual() || module_exists('locale')) {
3038
      $languages['language'] = db_query('SELECT * FROM {languages} ORDER BY weight ASC, name ASC')->fetchAllAssoc('language');
3039
      // Users cannot uninstall the native English language. However, we allow
3040
      // it to be hidden from the installed languages. Therefore, at least one
3041
      // other language must be enabled then.
3042
      if (!$languages['language']['en']->enabled && !variable_get('language_native_enabled', TRUE)) {
3043
        unset($languages['language']['en']);
3044
      }
3045
    }
3046
    else {
3047
      // No locale module, so use the default language only.
3048
      $default = language_default();
3049
      $languages['language'][$default->language] = $default;
3050
    }
3051
  }
3052

    
3053
  // Return the array indexed by the right field
3054
  if (!isset($languages[$field])) {
3055
    $languages[$field] = array();
3056
    foreach ($languages['language'] as $lang) {
3057
      // Some values should be collected into an array
3058
      if (in_array($field, array('enabled', 'weight'))) {
3059
        $languages[$field][$lang->$field][$lang->language] = $lang;
3060
      }
3061
      else {
3062
        $languages[$field][$lang->$field] = $lang;
3063
      }
3064
    }
3065
  }
3066
  return $languages[$field];
3067
}
3068

    
3069
/**
3070
 * Returns the default language, as an object, or one of its properties.
3071
 *
3072
 * @param $property
3073
 *   (optional) The property of the language object to return.
3074
 *
3075
 * @return
3076
 *   Either the language object for the default language used on the site,
3077
 *   or the property of that object named in the $property parameter.
3078
 */
3079
function language_default($property = NULL) {
3080
  $language = variable_get('language_default', (object) array('language' => 'en', 'name' => 'English', 'native' => 'English', 'direction' => 0, 'enabled' => 1, 'plurals' => 0, 'formula' => '', 'domain' => '', 'prefix' => '', 'weight' => 0, 'javascript' => ''));
3081
  return $property ? $language->$property : $language;
3082
}
3083

    
3084
/**
3085
 * Returns the requested URL path of the page being viewed.
3086
 *
3087
 * Examples:
3088
 * - http://example.com/node/306 returns "node/306".
3089
 * - http://example.com/drupalfolder/node/306 returns "node/306" while
3090
 *   base_path() returns "/drupalfolder/".
3091
 * - http://example.com/path/alias (which is a path alias for node/306) returns
3092
 *   "path/alias" as opposed to the internal path.
3093
 * - http://example.com/index.php returns an empty string (meaning: front page).
3094
 * - http://example.com/index.php?page=1 returns an empty string.
3095
 *
3096
 * @return
3097
 *   The requested Drupal URL path.
3098
 *
3099
 * @see current_path()
3100
 */
3101
function request_path() {
3102
  static $path;
3103

    
3104
  if (isset($path)) {
3105
    return $path;
3106
  }
3107

    
3108
  if (isset($_GET['q']) && is_string($_GET['q'])) {
3109
    // This is a request with a ?q=foo/bar query string. $_GET['q'] is
3110
    // overwritten in drupal_path_initialize(), but request_path() is called
3111
    // very early in the bootstrap process, so the original value is saved in
3112
    // $path and returned in later calls.
3113
    $path = $_GET['q'];
3114
  }
3115
  elseif (isset($_SERVER['REQUEST_URI'])) {
3116
    // This request is either a clean URL, or 'index.php', or nonsense.
3117
    // Extract the path from REQUEST_URI.
3118
    $request_path = strtok($_SERVER['REQUEST_URI'], '?');
3119
    $base_path_len = strlen(rtrim(dirname($_SERVER['SCRIPT_NAME']), '\/'));
3120
    // Unescape and strip $base_path prefix, leaving q without a leading slash.
3121
    $path = substr(urldecode($request_path), $base_path_len + 1);
3122
    // If the path equals the script filename, either because 'index.php' was
3123
    // explicitly provided in the URL, or because the server added it to
3124
    // $_SERVER['REQUEST_URI'] even when it wasn't provided in the URL (some
3125
    // versions of Microsoft IIS do this), the front page should be served.
3126
    if ($path == basename($_SERVER['PHP_SELF'])) {
3127
      $path = '';
3128
    }
3129
  }
3130
  else {
3131
    // This is the front page.
3132
    $path = '';
3133
  }
3134

    
3135
  // Under certain conditions Apache's RewriteRule directive prepends the value
3136
  // assigned to $_GET['q'] with a slash. Moreover we can always have a trailing
3137
  // slash in place, hence we need to normalize $_GET['q'].
3138
  $path = trim($path, '/');
3139

    
3140
  return $path;
3141
}
3142

    
3143
/**
3144
 * Returns a component of the current Drupal path.
3145
 *
3146
 * When viewing a page at the path "admin/structure/types", for example, arg(0)
3147
 * returns "admin", arg(1) returns "structure", and arg(2) returns "types".
3148
 *
3149
 * Avoid use of this function where possible, as resulting code is hard to
3150
 * read. In menu callback functions, attempt to use named arguments. See the
3151
 * explanation in menu.inc for how to construct callbacks that take arguments.
3152
 * When attempting to use this function to load an element from the current
3153
 * path, e.g. loading the node on a node page, use menu_get_object() instead.
3154
 *
3155
 * @param $index
3156
 *   The index of the component, where each component is separated by a '/'
3157
 *   (forward-slash), and where the first component has an index of 0 (zero).
3158
 * @param $path
3159
 *   A path to break into components. Defaults to the path of the current page.
3160
 *
3161
 * @return
3162
 *   The component specified by $index, or NULL if the specified component was
3163
 *   not found. If called without arguments, it returns an array containing all
3164
 *   the components of the current path.
3165
 */
3166
function arg($index = NULL, $path = NULL) {
3167
  // Even though $arguments doesn't need to be resettable for any functional
3168
  // reasons (the result of explode() does not depend on any run-time
3169
  // information), it should be resettable anyway in case a module needs to
3170
  // free up the memory used by it.
3171
  // Use the advanced drupal_static() pattern, since this is called very often.
3172
  static $drupal_static_fast;
3173
  if (!isset($drupal_static_fast)) {
3174
    $drupal_static_fast['arguments'] = &drupal_static(__FUNCTION__);
3175
  }
3176
  $arguments = &$drupal_static_fast['arguments'];
3177

    
3178
  if (!isset($path)) {
3179
    $path = $_GET['q'];
3180
  }
3181
  if (!isset($arguments[$path])) {
3182
    $arguments[$path] = explode('/', $path);
3183
  }
3184
  if (!isset($index)) {
3185
    return $arguments[$path];
3186
  }
3187
  if (isset($arguments[$path][$index])) {
3188
    return $arguments[$path][$index];
3189
  }
3190
}
3191

    
3192
/**
3193
 * Returns the IP address of the client machine.
3194
 *
3195
 * If Drupal is behind a reverse proxy, we use the X-Forwarded-For header
3196
 * instead of $_SERVER['REMOTE_ADDR'], which would be the IP address of
3197
 * the proxy server, and not the client's. The actual header name can be
3198
 * configured by the reverse_proxy_header variable.
3199
 *
3200
 * @return
3201
 *   IP address of client machine, adjusted for reverse proxy and/or cluster
3202
 *   environments.
3203
 */
3204
function ip_address() {
3205
  $ip_address = &drupal_static(__FUNCTION__);
3206

    
3207
  if (!isset($ip_address)) {
3208
    $ip_address = $_SERVER['REMOTE_ADDR'];
3209

    
3210
    if (variable_get('reverse_proxy', 0)) {
3211
      $reverse_proxy_header = variable_get('reverse_proxy_header', 'HTTP_X_FORWARDED_FOR');
3212
      if (!empty($_SERVER[$reverse_proxy_header])) {
3213
        // If an array of known reverse proxy IPs is provided, then trust
3214
        // the XFF header if request really comes from one of them.
3215
        $reverse_proxy_addresses = variable_get('reverse_proxy_addresses', array());
3216

    
3217
        // Turn XFF header into an array.
3218
        $forwarded = explode(',', $_SERVER[$reverse_proxy_header]);
3219

    
3220
        // Trim the forwarded IPs; they may have been delimited by commas and spaces.
3221
        $forwarded = array_map('trim', $forwarded);
3222

    
3223
        // Tack direct client IP onto end of forwarded array.
3224
        $forwarded[] = $ip_address;
3225

    
3226
        // Eliminate all trusted IPs.
3227
        $untrusted = array_diff($forwarded, $reverse_proxy_addresses);
3228

    
3229
        if (!empty($untrusted)) {
3230
          // The right-most IP is the most specific we can trust.
3231
          $ip_address = array_pop($untrusted);
3232
        }
3233
        else {
3234
          // All IP addresses in the forwarded array are configured proxy IPs
3235
          // (and thus trusted). We take the leftmost IP.
3236
          $ip_address = array_shift($forwarded);
3237
        }
3238
      }
3239
    }
3240
  }
3241

    
3242
  return $ip_address;
3243
}
3244

    
3245
/**
3246
 * @addtogroup schemaapi
3247
 * @{
3248
 */
3249

    
3250
/**
3251
 * Gets the schema definition of a table, or the whole database schema.
3252
 *
3253
 * The returned schema will include any modifications made by any
3254
 * module that implements hook_schema_alter(). To get the schema without
3255
 * modifications, use drupal_get_schema_unprocessed().
3256
 *
3257
 *
3258
 * @param $table
3259
 *   The name of the table. If not given, the schema of all tables is returned.
3260
 * @param $rebuild
3261
 *   If true, the schema will be rebuilt instead of retrieved from the cache.
3262
 */
3263
function drupal_get_schema($table = NULL, $rebuild = FALSE) {
3264
  static $schema;
3265

    
3266
  if ($rebuild || !isset($table)) {
3267
    $schema = drupal_get_complete_schema($rebuild);
3268
  }
3269
  elseif (!isset($schema)) {
3270
    $schema = new SchemaCache();
3271
  }
3272

    
3273
  if (!isset($table)) {
3274
    return $schema;
3275
  }
3276
  if (isset($schema[$table])) {
3277
    return $schema[$table];
3278
  }
3279
  else {
3280
    return FALSE;
3281
  }
3282
}
3283

    
3284
/**
3285
 * Extends DrupalCacheArray to allow for dynamic building of the schema cache.
3286
 */
3287
class SchemaCache extends DrupalCacheArray {
3288

    
3289
  /**
3290
   * Constructs a SchemaCache object.
3291
   */
3292
  public function __construct() {
3293
    // Cache by request method.
3294
    parent::__construct('schema:runtime:' . ($_SERVER['REQUEST_METHOD'] == 'GET'), 'cache');
3295
  }
3296

    
3297
  /**
3298
   * Overrides DrupalCacheArray::resolveCacheMiss().
3299
   */
3300
  protected function resolveCacheMiss($offset) {
3301
    $complete_schema = drupal_get_complete_schema();
3302
    $value = isset($complete_schema[$offset]) ? $complete_schema[$offset] :  NULL;
3303
    $this->storage[$offset] = $value;
3304
    $this->persist($offset);
3305
    return $value;
3306
  }
3307
}
3308

    
3309
/**
3310
 * Gets the whole database schema.
3311
 *
3312
 * The returned schema will include any modifications made by any
3313
 * module that implements hook_schema_alter().
3314
 *
3315
 * @param $rebuild
3316
 *   If true, the schema will be rebuilt instead of retrieved from the cache.
3317
 */
3318
function drupal_get_complete_schema($rebuild = FALSE) {
3319
  static $schema = array();
3320

    
3321
  if (empty($schema) || $rebuild) {
3322
    // Try to load the schema from cache.
3323
    if (!$rebuild && $cached = cache_get('schema')) {
3324
      $schema = $cached->data;
3325
    }
3326
    // Otherwise, rebuild the schema cache.
3327
    else {
3328
      $schema = array();
3329
      // Load the .install files to get hook_schema.
3330
      // On some databases this function may be called before bootstrap has
3331
      // been completed, so we force the functions we need to load just in case.
3332
      if (function_exists('module_load_all_includes')) {
3333
        // This function can be called very early in the bootstrap process, so
3334
        // we force the module_list() cache to be refreshed to ensure that it
3335
        // contains the complete list of modules before we go on to call
3336
        // module_load_all_includes().
3337
        module_list(TRUE);
3338
        module_load_all_includes('install');
3339
      }
3340

    
3341
      require_once DRUPAL_ROOT . '/includes/common.inc';
3342
      // Invoke hook_schema for all modules.
3343
      foreach (module_implements('schema') as $module) {
3344
        // Cast the result of hook_schema() to an array, as a NULL return value
3345
        // would cause array_merge() to set the $schema variable to NULL as well.
3346
        // That would break modules which use $schema further down the line.
3347
        $current = (array) module_invoke($module, 'schema');
3348
        // Set 'module' and 'name' keys for each table, and remove descriptions,
3349
        // as they needlessly slow down cache_get() for every single request.
3350
        _drupal_schema_initialize($current, $module);
3351
        $schema = array_merge($schema, $current);
3352
      }
3353

    
3354
      drupal_alter('schema', $schema);
3355
      // If the schema is empty, avoid saving it: some database engines require
3356
      // the schema to perform queries, and this could lead to infinite loops.
3357
      if (!empty($schema) && (drupal_get_bootstrap_phase() == DRUPAL_BOOTSTRAP_FULL)) {
3358
        cache_set('schema', $schema);
3359
      }
3360
      if ($rebuild) {
3361
        cache_clear_all('schema:', 'cache', TRUE);
3362
      }
3363
    }
3364
  }
3365

    
3366
  return $schema;
3367
}
3368

    
3369
/**
3370
 * @} End of "addtogroup schemaapi".
3371
 */
3372

    
3373

    
3374
/**
3375
 * @addtogroup registry
3376
 * @{
3377
 */
3378

    
3379
/**
3380
 * Confirms that an interface is available.
3381
 *
3382
 * This function is rarely called directly. Instead, it is registered as an
3383
 * spl_autoload()  handler, and PHP calls it for us when necessary.
3384
 *
3385
 * @param $interface
3386
 *   The name of the interface to check or load.
3387
 *
3388
 * @return
3389
 *   TRUE if the interface is currently available, FALSE otherwise.
3390
 */
3391
function drupal_autoload_interface($interface) {
3392
  return _registry_check_code('interface', $interface);
3393
}
3394

    
3395
/**
3396
 * Confirms that a class is available.
3397
 *
3398
 * This function is rarely called directly. Instead, it is registered as an
3399
 * spl_autoload()  handler, and PHP calls it for us when necessary.
3400
 *
3401
 * @param $class
3402
 *   The name of the class to check or load.
3403
 *
3404
 * @return
3405
 *   TRUE if the class is currently available, FALSE otherwise.
3406
 */
3407
function drupal_autoload_class($class) {
3408
  return _registry_check_code('class', $class);
3409
}
3410

    
3411
/**
3412
 * Confirms that a trait is available.
3413
 *
3414
 * This function is rarely called directly. Instead, it is registered as an
3415
 * spl_autoload() handler, and PHP calls it for us when necessary.
3416
 *
3417
 * @param string $trait
3418
 *   The name of the trait to check or load.
3419
 *
3420
 * @return bool
3421
 *   TRUE if the trait is currently available, FALSE otherwise.
3422
 */
3423
function drupal_autoload_trait($trait) {
3424
  return _registry_check_code('trait', $trait);
3425
}
3426

    
3427
/**
3428
 * Checks for a resource in the registry.
3429
 *
3430
 * @param $type
3431
 *   The type of resource we are looking up, or one of the constants
3432
 *   REGISTRY_RESET_LOOKUP_CACHE or REGISTRY_WRITE_LOOKUP_CACHE, which
3433
 *   signal that we should reset or write the cache, respectively.
3434
 * @param $name
3435
 *   The name of the resource, or NULL if either of the REGISTRY_* constants
3436
 *   is passed in.
3437
 *
3438
 * @return
3439
 *   TRUE if the resource was found, FALSE if not.
3440
 *   NULL if either of the REGISTRY_* constants is passed in as $type.
3441
 */
3442
function _registry_check_code($type, $name = NULL) {
3443
  static $lookup_cache, $cache_update_needed;
3444

    
3445
  if ($type == 'class' && class_exists($name) || $type == 'interface' && interface_exists($name) || $type == 'trait' && trait_exists($name)) {
3446
    return TRUE;
3447
  }
3448

    
3449
  if (!isset($lookup_cache)) {
3450
    $lookup_cache = array();
3451
    if ($cache = cache_get('lookup_cache', 'cache_bootstrap')) {
3452
      $lookup_cache = $cache->data;
3453
    }
3454
  }
3455

    
3456
  // When we rebuild the registry, we need to reset this cache so
3457
  // we don't keep lookups for resources that changed during the rebuild.
3458
  if ($type == REGISTRY_RESET_LOOKUP_CACHE) {
3459
    $cache_update_needed = TRUE;
3460
    $lookup_cache = NULL;
3461
    return;
3462
  }
3463

    
3464
  // Called from drupal_page_footer, we write to permanent storage if there
3465
  // changes to the lookup cache for this request.
3466
  if ($type == REGISTRY_WRITE_LOOKUP_CACHE) {
3467
    if ($cache_update_needed) {
3468
      cache_set('lookup_cache', $lookup_cache, 'cache_bootstrap');
3469
    }
3470
    return;
3471
  }
3472

    
3473
  // $type is either 'interface' or 'class', so we only need the first letter to
3474
  // keep the cache key unique.
3475
  $cache_key = $type[0] . $name;
3476
  if (isset($lookup_cache[$cache_key])) {
3477
    if ($lookup_cache[$cache_key]) {
3478
      include_once DRUPAL_ROOT . '/' . $lookup_cache[$cache_key];
3479
    }
3480
    return (bool) $lookup_cache[$cache_key];
3481
  }
3482

    
3483
  // This function may get called when the default database is not active, but
3484
  // there is no reason we'd ever want to not use the default database for
3485
  // this query.
3486
  $file = Database::getConnection('default', 'default')
3487
    ->select('registry', 'r', array('target' => 'default'))
3488
    ->fields('r', array('filename'))
3489
    // Use LIKE here to make the query case-insensitive.
3490
    ->condition('r.name', db_like($name), 'LIKE')
3491
    ->condition('r.type', $type)
3492
    ->execute()
3493
    ->fetchField();
3494

    
3495
  // Flag that we've run a lookup query and need to update the cache.
3496
  $cache_update_needed = TRUE;
3497

    
3498
  // Misses are valuable information worth caching, so cache even if
3499
  // $file is FALSE.
3500
  $lookup_cache[$cache_key] = $file;
3501

    
3502
  if ($file) {
3503
    include_once DRUPAL_ROOT . '/' . $file;
3504
    return TRUE;
3505
  }
3506
  else {
3507
    return FALSE;
3508
  }
3509
}
3510

    
3511
/**
3512
 * Rescans all enabled modules and rebuilds the registry.
3513
 *
3514
 * Rescans all code in modules or includes directories, storing the location of
3515
 * each interface or class in the database.
3516
 */
3517
function registry_rebuild() {
3518
  system_rebuild_module_data();
3519
  registry_update();
3520
}
3521

    
3522
/**
3523
 * Updates the registry based on the latest files listed in the database.
3524
 *
3525
 * This function should be used when system_rebuild_module_data() does not need
3526
 * to be called, because it is already known that the list of files in the
3527
 * {system} table matches those in the file system.
3528
 *
3529
 * @return
3530
 *   TRUE if the registry was rebuilt, FALSE if another thread was rebuilding
3531
 *   in parallel and the current thread just waited for completion.
3532
 *
3533
 * @see registry_rebuild()
3534
 */
3535
function registry_update() {
3536
  // install_system_module() calls module_enable() which calls into this
3537
  // function during initial system installation, so the lock system is neither
3538
  // loaded nor does its storage exist yet.
3539
  $in_installer = drupal_installation_attempted();
3540
  if (!$in_installer && !lock_acquire(__FUNCTION__)) {
3541
    // Another request got the lock, wait for it to finish.
3542
    lock_wait(__FUNCTION__);
3543
    return FALSE;
3544
  }
3545

    
3546
  require_once DRUPAL_ROOT . '/includes/registry.inc';
3547
  _registry_update();
3548

    
3549
  if (!$in_installer) {
3550
    lock_release(__FUNCTION__);
3551
  }
3552
  return TRUE;
3553
}
3554

    
3555
/**
3556
 * @} End of "addtogroup registry".
3557
 */
3558

    
3559
/**
3560
 * Provides central static variable storage.
3561
 *
3562
 * All functions requiring a static variable to persist or cache data within
3563
 * a single page request are encouraged to use this function unless it is
3564
 * absolutely certain that the static variable will not need to be reset during
3565
 * the page request. By centralizing static variable storage through this
3566
 * function, other functions can rely on a consistent API for resetting any
3567
 * other function's static variables.
3568
 *
3569
 * Example:
3570
 * @code
3571
 * function language_list($field = 'language') {
3572
 *   $languages = &drupal_static(__FUNCTION__);
3573
 *   if (!isset($languages)) {
3574
 *     // If this function is being called for the first time after a reset,
3575
 *     // query the database and execute any other code needed to retrieve
3576
 *     // information about the supported languages.
3577
 *     ...
3578
 *   }
3579
 *   if (!isset($languages[$field])) {
3580
 *     // If this function is being called for the first time for a particular
3581
 *     // index field, then execute code needed to index the information already
3582
 *     // available in $languages by the desired field.
3583
 *     ...
3584
 *   }
3585
 *   // Subsequent invocations of this function for a particular index field
3586
 *   // skip the above two code blocks and quickly return the already indexed
3587
 *   // information.
3588
 *   return $languages[$field];
3589
 * }
3590
 * function locale_translate_overview_screen() {
3591
 *   // When building the content for the translations overview page, make
3592
 *   // sure to get completely fresh information about the supported languages.
3593
 *   drupal_static_reset('language_list');
3594
 *   ...
3595
 * }
3596
 * @endcode
3597
 *
3598
 * In a few cases, a function can have certainty that there is no legitimate
3599
 * use-case for resetting that function's static variable. This is rare,
3600
 * because when writing a function, it's hard to forecast all the situations in
3601
 * which it will be used. A guideline is that if a function's static variable
3602
 * does not depend on any information outside of the function that might change
3603
 * during a single page request, then it's ok to use the "static" keyword
3604
 * instead of the drupal_static() function.
3605
 *
3606
 * Example:
3607
 * @code
3608
 * function actions_do(...) {
3609
 *   // $stack tracks the number of recursive calls.
3610
 *   static $stack;
3611
 *   $stack++;
3612
 *   if ($stack > variable_get('actions_max_stack', 35)) {
3613
 *     ...
3614
 *     return;
3615
 *   }
3616
 *   ...
3617
 *   $stack--;
3618
 * }
3619
 * @endcode
3620
 *
3621
 * In a few cases, a function needs a resettable static variable, but the
3622
 * function is called many times (100+) during a single page request, so
3623
 * every microsecond of execution time that can be removed from the function
3624
 * counts. These functions can use a more cumbersome, but faster variant of
3625
 * calling drupal_static(). It works by storing the reference returned by
3626
 * drupal_static() in the calling function's own static variable, thereby
3627
 * removing the need to call drupal_static() for each iteration of the function.
3628
 * Conceptually, it replaces:
3629
 * @code
3630
 * $foo = &drupal_static(__FUNCTION__);
3631
 * @endcode
3632
 * with:
3633
 * @code
3634
 * // Unfortunately, this does not work.
3635
 * static $foo = &drupal_static(__FUNCTION__);
3636
 * @endcode
3637
 * However, the above line of code does not work, because PHP only allows static
3638
 * variables to be initializied by literal values, and does not allow static
3639
 * variables to be assigned to references.
3640
 * - http://php.net/manual/language.variables.scope.php#language.variables.scope.static
3641
 * - http://php.net/manual/language.variables.scope.php#language.variables.scope.references
3642
 * The example below shows the syntax needed to work around both limitations.
3643
 * For benchmarks and more information, see http://drupal.org/node/619666.
3644
 *
3645
 * Example:
3646
 * @code
3647
 * function user_access($string, $account = NULL) {
3648
 *   // Use the advanced drupal_static() pattern, since this is called very often.
3649
 *   static $drupal_static_fast;
3650
 *   if (!isset($drupal_static_fast)) {
3651
 *     $drupal_static_fast['perm'] = &drupal_static(__FUNCTION__);
3652
 *   }
3653
 *   $perm = &$drupal_static_fast['perm'];
3654
 *   ...
3655
 * }
3656
 * @endcode
3657
 *
3658
 * @param $name
3659
 *   Globally unique name for the variable. For a function with only one static,
3660
 *   variable, the function name (e.g. via the PHP magic __FUNCTION__ constant)
3661
 *   is recommended. For a function with multiple static variables add a
3662
 *   distinguishing suffix to the function name for each one.
3663
 * @param $default_value
3664
 *   Optional default value.
3665
 * @param $reset
3666
 *   TRUE to reset one or all variables(s). This parameter is only used
3667
 *   internally and should not be passed in; use drupal_static_reset() instead.
3668
 *   (This function's return value should not be used when TRUE is passed in.)
3669
 *
3670
 * @return
3671
 *   Returns a variable by reference.
3672
 *
3673
 * @see drupal_static_reset()
3674
 */
3675
function &drupal_static($name, $default_value = NULL, $reset = FALSE) {
3676
  static $data = array(), $default = array();
3677
  // First check if dealing with a previously defined static variable.
3678
  if (isset($data[$name]) || array_key_exists($name, $data)) {
3679
    // Non-NULL $name and both $data[$name] and $default[$name] statics exist.
3680
    if ($reset) {
3681
      // Reset pre-existing static variable to its default value.
3682
      $data[$name] = $default[$name];
3683
    }
3684
    return $data[$name];
3685
  }
3686
  // Neither $data[$name] nor $default[$name] static variables exist.
3687
  if (isset($name)) {
3688
    if ($reset) {
3689
      // Reset was called before a default is set and yet a variable must be
3690
      // returned.
3691
      return $data;
3692
    }
3693
    // First call with new non-NULL $name. Initialize a new static variable.
3694
    $default[$name] = $data[$name] = $default_value;
3695
    return $data[$name];
3696
  }
3697
  // Reset all: ($name == NULL). This needs to be done one at a time so that
3698
  // references returned by earlier invocations of drupal_static() also get
3699
  // reset.
3700
  foreach ($default as $name => $value) {
3701
    $data[$name] = $value;
3702
  }
3703
  // As the function returns a reference, the return should always be a
3704
  // variable.
3705
  return $data;
3706
}
3707

    
3708
/**
3709
 * Resets one or all centrally stored static variable(s).
3710
 *
3711
 * @param $name
3712
 *   Name of the static variable to reset. Omit to reset all variables.
3713
 *   Resetting all variables should only be used, for example, for running unit
3714
 *   tests with a clean environment.
3715
 */
3716
function drupal_static_reset($name = NULL) {
3717
  drupal_static($name, NULL, TRUE);
3718
}
3719

    
3720
/**
3721
 * Detects whether the current script is running in a command-line environment.
3722
 */
3723
function drupal_is_cli() {
3724
  return (!isset($_SERVER['SERVER_SOFTWARE']) && (php_sapi_name() == 'cli' || (is_numeric($_SERVER['argc']) && $_SERVER['argc'] > 0)));
3725
}
3726

    
3727
/**
3728
 * Formats text for emphasized display in a placeholder inside a sentence.
3729
 *
3730
 * Used automatically by format_string().
3731
 *
3732
 * @param $text
3733
 *   The text to format (plain-text).
3734
 *
3735
 * @return
3736
 *   The formatted text (html).
3737
 */
3738
function drupal_placeholder($text) {
3739
  return '<em class="placeholder">' . check_plain($text) . '</em>';
3740
}
3741

    
3742
/**
3743
 * Registers a function for execution on shutdown.
3744
 *
3745
 * Wrapper for register_shutdown_function() that catches thrown exceptions to
3746
 * avoid "Exception thrown without a stack frame in Unknown".
3747
 *
3748
 * @param $callback
3749
 *   The shutdown function to register.
3750
 * @param ...
3751
 *   Additional arguments to pass to the shutdown function.
3752
 *
3753
 * @return
3754
 *   Array of shutdown functions to be executed.
3755
 *
3756
 * @see register_shutdown_function()
3757
 * @ingroup php_wrappers
3758
 */
3759
function &drupal_register_shutdown_function($callback = NULL) {
3760
  // We cannot use drupal_static() here because the static cache is reset during
3761
  // batch processing, which breaks batch handling.
3762
  static $callbacks = array();
3763

    
3764
  if (isset($callback)) {
3765
    // Only register the internal shutdown function once.
3766
    if (empty($callbacks)) {
3767
      register_shutdown_function('_drupal_shutdown_function');
3768
    }
3769
    $args = func_get_args();
3770
    array_shift($args);
3771
    // Save callback and arguments
3772
    $callbacks[] = array('callback' => $callback, 'arguments' => $args);
3773
  }
3774
  return $callbacks;
3775
}
3776

    
3777
/**
3778
 * Executes registered shutdown functions.
3779
 */
3780
function _drupal_shutdown_function() {
3781
  $callbacks = &drupal_register_shutdown_function();
3782

    
3783
  // Set the CWD to DRUPAL_ROOT as it is not guaranteed to be the same as it
3784
  // was in the normal context of execution.
3785
  chdir(DRUPAL_ROOT);
3786

    
3787
  try {
3788
    while (list($key, $callback) = each($callbacks)) {
3789
      call_user_func_array($callback['callback'], $callback['arguments']);
3790
    }
3791
  }
3792
  catch (Exception $exception) {
3793
    // If we are displaying errors, then do so with no possibility of a further uncaught exception being thrown.
3794
   require_once DRUPAL_ROOT . '/includes/errors.inc';
3795
   if (error_displayable()) {
3796
      print '<h1>Uncaught exception thrown in shutdown function.</h1>';
3797
      print '<p>' . _drupal_render_exception_safe($exception) . '</p><hr />';
3798
    }
3799
  }
3800
}
3801

    
3802
/**
3803
 * Compares the memory required for an operation to the available memory.
3804
 *
3805
 * @param $required
3806
 *   The memory required for the operation, expressed as a number of bytes with
3807
 *   optional SI or IEC binary unit prefix (e.g. 2, 3K, 5MB, 10G, 6GiB, 8bytes,
3808
 *   9mbytes).
3809
 * @param $memory_limit
3810
 *   (optional) The memory limit for the operation, expressed as a number of
3811
 *   bytes with optional SI or IEC binary unit prefix (e.g. 2, 3K, 5MB, 10G,
3812
 *   6GiB, 8bytes, 9mbytes). If no value is passed, the current PHP
3813
 *   memory_limit will be used. Defaults to NULL.
3814
 *
3815
 * @return
3816
 *   TRUE if there is sufficient memory to allow the operation, or FALSE
3817
 *   otherwise.
3818
 */
3819
function drupal_check_memory_limit($required, $memory_limit = NULL) {
3820
  if (!isset($memory_limit)) {
3821
    $memory_limit = ini_get('memory_limit');
3822
  }
3823

    
3824
  // There is sufficient memory if:
3825
  // - No memory limit is set.
3826
  // - The memory limit is set to unlimited (-1).
3827
  // - The memory limit is greater than the memory required for the operation.
3828
  return ((!$memory_limit) || ($memory_limit == -1) || (parse_size($memory_limit) >= parse_size($required)));
3829
}
3830

    
3831
/**
3832
 * Invalidates a PHP file from any active opcode caches.
3833
 *
3834
 * If the opcode cache does not support the invalidation of individual files,
3835
 * the entire cache will be flushed.
3836
 *
3837
 * @param string $filepath
3838
 *   The absolute path of the PHP file to invalidate.
3839
 */
3840
function drupal_clear_opcode_cache($filepath) {
3841
  if (!defined('PHP_VERSION_ID') || PHP_VERSION_ID < 50300) {
3842
    // Below PHP 5.3, clearstatcache does not accept any function parameters.
3843
    clearstatcache();
3844
  }
3845
  else {
3846
    clearstatcache(TRUE, $filepath);
3847
  }
3848

    
3849
  // Zend OPcache.
3850
  if (function_exists('opcache_invalidate')) {
3851
    opcache_invalidate($filepath, TRUE);
3852
  }
3853
  // APC.
3854
  if (function_exists('apc_delete_file')) {
3855
    // apc_delete_file() throws a PHP warning in case the specified file was
3856
    // not compiled yet.
3857
    // @see http://php.net/apc-delete-file
3858
    @apc_delete_file($filepath);
3859
  }
3860
}