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root / drupal7 / includes / bootstrap.inc @ c7768a53

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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
 */
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define('VERSION', '7.78');
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/**
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 * Core API compatibility.
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 */
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define('DRUPAL_CORE_COMPATIBILITY', '7.x');
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/**
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 * Minimum supported version of PHP.
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 */
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define('DRUPAL_MINIMUM_PHP', '5.2.4');
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/**
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 * Minimum recommended value of PHP memory_limit.
25
 */
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define('DRUPAL_MINIMUM_PHP_MEMORY_LIMIT', '32M');
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28
/**
29
 * Error reporting level: display no errors.
30
 */
31
define('ERROR_REPORTING_HIDE', 0);
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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);
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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
 */
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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
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 * correspond to RFC 3164. The associated PHP bug report was closed with the
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 * comment, "And it's also not a bug, as Windows just have less log levels,"
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 * 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
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 * @see http://php.net/manual/function.syslog.php
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 * @see http://php.net/manual/network.constants.php
71
 * @see watchdog()
72
 * @see watchdog_severity_levels()
73
 */
74

    
75
/**
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 * 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);
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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);
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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);
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/**
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 * Log message severity -- Informational messages.
107
 */
108
define('WATCHDOG_INFO', 6);
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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);
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124
/**
125
 * Second bootstrap phase: try to serve a cached page.
126
 */
127
define('DRUPAL_BOOTSTRAP_PAGE_CACHE', 1);
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129
/**
130
 * Third bootstrap phase: initialize database layer.
131
 */
132
define('DRUPAL_BOOTSTRAP_DATABASE', 2);
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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);
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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');
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198
/**
199
 * Language written left to right. Possible value of $language->direction.
200
 */
201
define('LANGUAGE_LTR', 0);
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203
/**
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 * 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
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 * @see http://php.net/manual/function.time.php
217
 */
218
define('REQUEST_TIME', (int) $_SERVER['REQUEST_TIME']);
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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);
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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]*');
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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
}
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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
  // PHP's built-in phar:// stream wrapper is not sufficiently secure. Override
709
  // it with a more secure one, which requires PHP 5.3.3. For lower versions,
710
  // unregister the built-in one without replacing it. Sites needing phar
711
  // support for lower PHP versions must implement hook_stream_wrappers() to
712
  // register their desired implementation.
713
  if (in_array('phar', stream_get_wrappers(), TRUE)) {
714
    stream_wrapper_unregister('phar');
715
    if (version_compare(PHP_VERSION, '5.3.3', '>=')) {
716
      include_once DRUPAL_ROOT . '/includes/file.phar.inc';
717
      file_register_phar_wrapper();
718
    }
719
  }
720
}
721

    
722
/**
723
 * Validates that a hostname (for example $_SERVER['HTTP_HOST']) is safe.
724
 *
725
 * @return
726
 *  TRUE if only containing valid characters, or FALSE otherwise.
727
 */
728
function drupal_valid_http_host($host) {
729
  // Limit the length of the host name to 1000 bytes to prevent DoS attacks with
730
  // long host names.
731
  return strlen($host) <= 1000
732
    // Limit the number of subdomains and port separators to prevent DoS attacks
733
    // in conf_path().
734
    && substr_count($host, '.') <= 100
735
    && substr_count($host, ':') <= 100
736
    && preg_match('/^\[?(?:[a-zA-Z0-9-:\]_]+\.?)+$/', $host);
737
}
738

    
739
/**
740
 * Checks whether an HTTPS request is being served.
741
 *
742
 * @return bool
743
 *   TRUE if the request is HTTPS, FALSE otherwise.
744
 */
745
function drupal_is_https() {
746
  return isset($_SERVER['HTTPS']) && strtolower($_SERVER['HTTPS']) == 'on';
747
}
748

    
749
/**
750
 * Sets the base URL, cookie domain, and session name from configuration.
751
 */
752
function drupal_settings_initialize() {
753
  global $base_url, $base_path, $base_root;
754

    
755
  // Export these settings.php variables to the global namespace.
756
  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;
757
  $conf = array();
758

    
759
  if (file_exists(DRUPAL_ROOT . '/' . conf_path() . '/settings.php')) {
760
    include_once DRUPAL_ROOT . '/' . conf_path() . '/settings.php';
761
  }
762
  $is_https = drupal_is_https();
763

    
764
  if (isset($base_url)) {
765
    // Parse fixed base URL from settings.php.
766
    $parts = parse_url($base_url);
767
    if (!isset($parts['path'])) {
768
      $parts['path'] = '';
769
    }
770
    $base_path = $parts['path'] . '/';
771
    // Build $base_root (everything until first slash after "scheme://").
772
    $base_root = substr($base_url, 0, strlen($base_url) - strlen($parts['path']));
773
  }
774
  else {
775
    // Create base URL.
776
    $http_protocol = $is_https ? 'https' : 'http';
777
    $base_root = $http_protocol . '://' . $_SERVER['HTTP_HOST'];
778

    
779
    $base_url = $base_root;
780

    
781
    // $_SERVER['SCRIPT_NAME'] can, in contrast to $_SERVER['PHP_SELF'], not
782
    // be modified by a visitor.
783
    if ($dir = rtrim(dirname($_SERVER['SCRIPT_NAME']), '\/')) {
784
      $base_path = $dir;
785
      $base_url .= $base_path;
786
      $base_path .= '/';
787
    }
788
    else {
789
      $base_path = '/';
790
    }
791
  }
792
  $base_secure_url = str_replace('http://', 'https://', $base_url);
793
  $base_insecure_url = str_replace('https://', 'http://', $base_url);
794

    
795
  if ($cookie_domain) {
796
    // If the user specifies the cookie domain, also use it for session name.
797
    $session_name = $cookie_domain;
798
  }
799
  else {
800
    // Otherwise use $base_url as session name, without the protocol
801
    // to use the same session identifiers across HTTP and HTTPS.
802
    list( , $session_name) = explode('://', $base_url, 2);
803
    // HTTP_HOST can be modified by a visitor, but we already sanitized it
804
    // in drupal_settings_initialize().
805
    if (!empty($_SERVER['HTTP_HOST'])) {
806
      $cookie_domain = $_SERVER['HTTP_HOST'];
807
      // Strip leading periods, www., and port numbers from cookie domain.
808
      $cookie_domain = ltrim($cookie_domain, '.');
809
      if (strpos($cookie_domain, 'www.') === 0) {
810
        $cookie_domain = substr($cookie_domain, 4);
811
      }
812
      $cookie_domain = explode(':', $cookie_domain);
813
      $cookie_domain = '.' . $cookie_domain[0];
814
    }
815
  }
816
  // Per RFC 2109, cookie domains must contain at least one dot other than the
817
  // first. For hosts such as 'localhost' or IP Addresses we don't set a cookie domain.
818
  if (count(explode('.', $cookie_domain)) > 2 && !is_numeric(str_replace('.', '', $cookie_domain))) {
819
    ini_set('session.cookie_domain', $cookie_domain);
820
  }
821
  // To prevent session cookies from being hijacked, a user can configure the
822
  // SSL version of their website to only transfer session cookies via SSL by
823
  // using PHP's session.cookie_secure setting. The browser will then use two
824
  // separate session cookies for the HTTPS and HTTP versions of the site. So we
825
  // must use different session identifiers for HTTPS and HTTP to prevent a
826
  // cookie collision.
827
  if ($is_https) {
828
    ini_set('session.cookie_secure', TRUE);
829
  }
830
  $prefix = ini_get('session.cookie_secure') ? 'SSESS' : 'SESS';
831
  session_name($prefix . substr(hash('sha256', $session_name), 0, 32));
832
}
833

    
834
/**
835
 * Returns and optionally sets the filename for a system resource.
836
 *
837
 * The filename, whether provided, cached, or retrieved from the database, is
838
 * only returned if the file exists.
839
 *
840
 * This function plays a key role in allowing Drupal's resources (modules
841
 * and themes) to be located in different places depending on a site's
842
 * configuration. For example, a module 'foo' may legally be located
843
 * in any of these three places:
844
 *
845
 * modules/foo/foo.module
846
 * sites/all/modules/foo/foo.module
847
 * sites/example.com/modules/foo/foo.module
848
 *
849
 * Calling drupal_get_filename('module', 'foo') will give you one of
850
 * the above, depending on where the module is located.
851
 *
852
 * @param $type
853
 *   The type of the item (theme, theme_engine, module, profile).
854
 * @param $name
855
 *   The name of the item for which the filename is requested.
856
 * @param $filename
857
 *   The filename of the item if it is to be set explicitly rather
858
 *   than by consulting the database.
859
 * @param bool $trigger_error
860
 *   Whether to trigger an error when a file is missing or has unexpectedly
861
 *   moved. This defaults to TRUE, but can be set to FALSE by calling code that
862
 *   merely wants to check whether an item exists in the filesystem.
863
 *
864
 * @return
865
 *   The filename of the requested item or NULL if the item is not found.
866
 */
867
function drupal_get_filename($type, $name, $filename = NULL, $trigger_error = TRUE) {
868
  // The $files static variable will hold the locations of all requested files.
869
  // We can be sure that any file listed in this static variable actually
870
  // exists as all additions have gone through a file_exists() check.
871
  // The location of files will not change during the request, so do not use
872
  // drupal_static().
873
  static $files = array();
874

    
875
  // Profiles are a special case: they have a fixed location and naming.
876
  if ($type == 'profile') {
877
    $profile_filename = "profiles/$name/$name.profile";
878
    $files[$type][$name] = file_exists($profile_filename) ? $profile_filename : FALSE;
879
  }
880
  if (!isset($files[$type])) {
881
    $files[$type] = array();
882
  }
883

    
884
  if (!empty($filename) && file_exists($filename)) {
885
    // Prime the static cache with the provided filename.
886
    $files[$type][$name] = $filename;
887
  }
888
  elseif (isset($files[$type][$name])) {
889
    // This item had already been found earlier in the request, either through
890
    // priming of the static cache (for example, in system_list()), through a
891
    // lookup in the {system} table, or through a file scan (cached or not). Do
892
    // nothing.
893
  }
894
  else {
895
    // Look for the filename listed in the {system} table. Verify that we have
896
    // an active database connection before doing so, since this function is
897
    // called both before we have a database connection (i.e. during
898
    // installation) and when a database connection fails.
899
    $database_unavailable = TRUE;
900
    try {
901
      if (function_exists('db_query')) {
902
        $file = db_query("SELECT filename FROM {system} WHERE name = :name AND type = :type", array(':name' => $name, ':type' => $type))->fetchField();
903
        if ($file !== FALSE && file_exists(DRUPAL_ROOT . '/' . $file)) {
904
          $files[$type][$name] = $file;
905
        }
906
        $database_unavailable = FALSE;
907
      }
908
    }
909
    catch (Exception $e) {
910
      // The database table may not exist because Drupal is not yet installed,
911
      // the database might be down, or we may have done a non-database cache
912
      // flush while $conf['page_cache_without_database'] = TRUE and
913
      // $conf['page_cache_invoke_hooks'] = TRUE. We have a fallback for these
914
      // cases so we hide the error completely.
915
    }
916
    // Fall back to searching the filesystem if the database could not find the
917
    // file or the file does not exist at the path returned by the database.
918
    if (!isset($files[$type][$name])) {
919
      $files[$type][$name] = _drupal_get_filename_fallback($type, $name, $trigger_error, $database_unavailable);
920
    }
921
  }
922

    
923
  if (isset($files[$type][$name])) {
924
    return $files[$type][$name];
925
  }
926
}
927

    
928
/**
929
 * Performs a cached file system scan as a fallback when searching for a file.
930
 *
931
 * This function looks for the requested file by triggering a file scan,
932
 * caching the new location if the file has moved and caching the miss
933
 * if the file is missing. If a file had been marked as missing in a previous
934
 * file scan, or if it has been marked as moved and is still in the last known
935
 * location, no new file scan will be performed.
936
 *
937
 * @param string $type
938
 *   The type of the item (theme, theme_engine, module, profile).
939
 * @param string $name
940
 *   The name of the item for which the filename is requested.
941
 * @param bool $trigger_error
942
 *   Whether to trigger an error when a file is missing or has unexpectedly
943
 *   moved.
944
 * @param bool $database_unavailable
945
 *   Whether this function is being called because the Drupal database could
946
 *   not be queried for the file's location.
947
 *
948
 * @return
949
 *   The filename of the requested item or NULL if the item is not found.
950
 *
951
 * @see drupal_get_filename()
952
 */
953
function _drupal_get_filename_fallback($type, $name, $trigger_error, $database_unavailable) {
954
  $file_scans = &_drupal_file_scan_cache();
955
  $filename = NULL;
956

    
957
  // If the cache indicates that the item is missing, or we can verify that the
958
  // item exists in the location the cache says it exists in, use that.
959
  if (isset($file_scans[$type][$name]) && ($file_scans[$type][$name] === FALSE || file_exists($file_scans[$type][$name]))) {
960
    $filename = $file_scans[$type][$name];
961
  }
962
  // Otherwise, perform a new file scan to find the item.
963
  else {
964
    $filename = _drupal_get_filename_perform_file_scan($type, $name);
965
    // Update the static cache, and mark the persistent cache for updating at
966
    // the end of the page request. See drupal_file_scan_write_cache().
967
    $file_scans[$type][$name] = $filename;
968
    $file_scans['#write_cache'] = TRUE;
969
  }
970

    
971
  // If requested, trigger a user-level warning about the missing or
972
  // unexpectedly moved file. If the database was unavailable, do not trigger a
973
  // warning in the latter case, though, since if the {system} table could not
974
  // be queried there is no way to know if the location found here was
975
  // "unexpected" or not.
976
  if ($trigger_error) {
977
    $error_type = $filename === FALSE ? 'missing' : 'moved';
978
    if ($error_type == 'missing' || !$database_unavailable) {
979
      _drupal_get_filename_fallback_trigger_error($type, $name, $error_type);
980
    }
981
  }
982

    
983
  // The cache stores FALSE for files that aren't found (to be able to
984
  // distinguish them from files that have not yet been searched for), but
985
  // drupal_get_filename() expects NULL for these instead, so convert to NULL
986
  // before returning.
987
  if ($filename === FALSE) {
988
    $filename = NULL;
989
  }
990
  return $filename;
991
}
992

    
993
/**
994
 * Returns the current list of cached file system scan results.
995
 *
996
 * @return
997
 *   An associative array tracking the most recent file scan results for all
998
 *   files that have had scans performed. The keys are the type and name of the
999
 *   item that was searched for, and the values can be either:
1000
 *   - Boolean FALSE if the item was not found in the file system.
1001
 *   - A string pointing to the location where the item was found.
1002
 */
1003
function &_drupal_file_scan_cache() {
1004
  $file_scans = &drupal_static(__FUNCTION__, array());
1005

    
1006
  // The file scan results are stored in a persistent cache (in addition to the
1007
  // static cache) but because this function can be called before the
1008
  // persistent cache is available, we must merge any items that were found
1009
  // earlier in the page request into the results from the persistent cache.
1010
  if (!isset($file_scans['#cache_merge_done'])) {
1011
    try {
1012
      if (function_exists('cache_get')) {
1013
        $cache = cache_get('_drupal_file_scan_cache', 'cache_bootstrap');
1014
        if (!empty($cache->data)) {
1015
          // File scan results from the current request should take precedence
1016
          // over the results from the persistent cache, since they are newer.
1017
          $file_scans = drupal_array_merge_deep($cache->data, $file_scans);
1018
        }
1019
        // Set a flag to indicate that the persistent cache does not need to be
1020
        // merged again.
1021
        $file_scans['#cache_merge_done'] = TRUE;
1022
      }
1023
    }
1024
    catch (Exception $e) {
1025
      // Hide the error.
1026
    }
1027
  }
1028

    
1029
  return $file_scans;
1030
}
1031

    
1032
/**
1033
 * Performs a file system scan to search for a system resource.
1034
 *
1035
 * @param $type
1036
 *   The type of the item (theme, theme_engine, module, profile).
1037
 * @param $name
1038
 *   The name of the item for which the filename is requested.
1039
 *
1040
 * @return
1041
 *   The filename of the requested item or FALSE if the item is not found.
1042
 *
1043
 * @see drupal_get_filename()
1044
 * @see _drupal_get_filename_fallback()
1045
 */
1046
function _drupal_get_filename_perform_file_scan($type, $name) {
1047
  // The location of files will not change during the request, so do not use
1048
  // drupal_static().
1049
  static $dirs = array(), $files = array();
1050

    
1051
  // We have a consistent directory naming: modules, themes...
1052
  $dir = $type . 's';
1053
  if ($type == 'theme_engine') {
1054
    $dir = 'themes/engines';
1055
    $extension = 'engine';
1056
  }
1057
  elseif ($type == 'theme') {
1058
    $extension = 'info';
1059
  }
1060
  else {
1061
    $extension = $type;
1062
  }
1063

    
1064
  // Check if we had already scanned this directory/extension combination.
1065
  if (!isset($dirs[$dir][$extension])) {
1066
    // Log that we have now scanned this directory/extension combination
1067
    // into a static variable so as to prevent unnecessary file scans.
1068
    $dirs[$dir][$extension] = TRUE;
1069
    if (!function_exists('drupal_system_listing')) {
1070
      require_once DRUPAL_ROOT . '/includes/common.inc';
1071
    }
1072
    // Scan the appropriate directories for all files with the requested
1073
    // extension, not just the file we are currently looking for. This
1074
    // prevents unnecessary scans from being repeated when this function is
1075
    // called more than once in the same page request.
1076
    $matches = drupal_system_listing("/^" . DRUPAL_PHP_FUNCTION_PATTERN . "\.$extension$/", $dir, 'name', 0);
1077
    foreach ($matches as $matched_name => $file) {
1078
      // Log the locations found in the file scan into a static variable.
1079
      $files[$type][$matched_name] = $file->uri;
1080
    }
1081
  }
1082

    
1083
  // Return the results of the file system scan, or FALSE to indicate the file
1084
  // was not found.
1085
  return isset($files[$type][$name]) ? $files[$type][$name] : FALSE;
1086
}
1087

    
1088
/**
1089
 * Triggers a user-level warning for missing or unexpectedly moved files.
1090
 *
1091
 * @param $type
1092
 *   The type of the item (theme, theme_engine, module, profile).
1093
 * @param $name
1094
 *   The name of the item for which the filename is requested.
1095
 * @param $error_type
1096
 *   The type of the error ('missing' or 'moved').
1097
 *
1098
 * @see drupal_get_filename()
1099
 * @see _drupal_get_filename_fallback()
1100
 */
1101
function _drupal_get_filename_fallback_trigger_error($type, $name, $error_type) {
1102
  // Hide messages due to known bugs that will appear on a lot of sites.
1103
  // @todo Remove this in https://www.drupal.org/node/2383823
1104
  if (empty($name)) {
1105
    return;
1106
  }
1107

    
1108
  // Make sure we only show any missing or moved file errors only once per
1109
  // request.
1110
  static $errors_triggered = array();
1111
  if (empty($errors_triggered[$type][$name][$error_type])) {
1112
    // Use _drupal_trigger_error_with_delayed_logging() here since these are
1113
    // triggered during low-level operations that cannot necessarily be
1114
    // interrupted by a watchdog() call.
1115
    if ($error_type == 'missing') {
1116
      _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' => $name, '@documentation' => 'https://www.drupal.org/node/2487215')), E_USER_WARNING);
1117
    }
1118
    elseif ($error_type == 'moved') {
1119
      _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);
1120
    }
1121
    $errors_triggered[$type][$name][$error_type] = TRUE;
1122
  }
1123
}
1124

    
1125
/**
1126
 * Invokes trigger_error() with logging delayed until the end of the request.
1127
 *
1128
 * This is an alternative to PHP's trigger_error() function which can be used
1129
 * during low-level Drupal core operations that need to avoid being interrupted
1130
 * by a watchdog() call.
1131
 *
1132
 * Normally, Drupal's error handler calls watchdog() in response to a
1133
 * trigger_error() call. However, this invokes hook_watchdog() which can run
1134
 * arbitrary code. If the trigger_error() happens in the middle of an
1135
 * operation such as a rebuild operation which should not be interrupted by
1136
 * arbitrary code, that could potentially break or trigger the rebuild again.
1137
 * This function protects against that by delaying the watchdog() call until
1138
 * the end of the current page request.
1139
 *
1140
 * This is an internal function which should only be called by low-level Drupal
1141
 * core functions. It may be removed in a future Drupal 7 release.
1142
 *
1143
 * @param string $error_msg
1144
 *   The error message to trigger. As with trigger_error() itself, this is
1145
 *   limited to 1024 bytes; additional characters beyond that will be removed.
1146
 * @param int $error_type
1147
 *   (optional) The type of error. This should be one of the E_USER family of
1148
 *   constants. As with trigger_error() itself, this defaults to E_USER_NOTICE
1149
 *   if not provided.
1150
 *
1151
 * @see _drupal_log_error()
1152
 */
1153
function _drupal_trigger_error_with_delayed_logging($error_msg, $error_type = E_USER_NOTICE) {
1154
  $delay_logging = &drupal_static(__FUNCTION__, FALSE);
1155
  $delay_logging = TRUE;
1156
  trigger_error($error_msg, $error_type);
1157
  $delay_logging = FALSE;
1158
}
1159

    
1160
/**
1161
 * Writes the file scan cache to the persistent cache.
1162
 *
1163
 * This cache stores all files marked as missing or moved after a file scan
1164
 * to prevent unnecessary file scans in subsequent requests. This cache is
1165
 * cleared in system_list_reset() (i.e. after a module/theme rebuild).
1166
 */
1167
function drupal_file_scan_write_cache() {
1168
  // Only write to the persistent cache if requested, and if we know that any
1169
  // data previously in the cache was successfully loaded and merged in by
1170
  // _drupal_file_scan_cache().
1171
  $file_scans = &_drupal_file_scan_cache();
1172
  if (isset($file_scans['#write_cache']) && isset($file_scans['#cache_merge_done'])) {
1173
    unset($file_scans['#write_cache']);
1174
    cache_set('_drupal_file_scan_cache', $file_scans, 'cache_bootstrap');
1175
  }
1176
}
1177

    
1178
/**
1179
 * Loads the persistent variable table.
1180
 *
1181
 * The variable table is composed of values that have been saved in the table
1182
 * with variable_set() as well as those explicitly specified in the
1183
 * configuration file.
1184
 */
1185
function variable_initialize($conf = array()) {
1186
  // NOTE: caching the variables improves performance by 20% when serving
1187
  // cached pages.
1188
  if ($cached = cache_get('variables', 'cache_bootstrap')) {
1189
    $variables = $cached->data;
1190
  }
1191
  else {
1192
    // Cache miss. Avoid a stampede by acquiring a lock. If the lock fails to
1193
    // acquire, optionally just continue with uncached processing.
1194
    $name = 'variable_init';
1195
    $lock_acquired = lock_acquire($name, 1);
1196
    if (!$lock_acquired && variable_get('variable_initialize_wait_for_lock', FALSE)) {
1197
      lock_wait($name);
1198
      return variable_initialize($conf);
1199
    }
1200
    else {
1201
      // Load the variables from the table.
1202
      $variables = array_map('unserialize', db_query('SELECT name, value FROM {variable}')->fetchAllKeyed());
1203
      if ($lock_acquired) {
1204
        cache_set('variables', $variables, 'cache_bootstrap');
1205
        lock_release($name);
1206
      }
1207
    }
1208
  }
1209

    
1210
  foreach ($conf as $name => $value) {
1211
    $variables[$name] = $value;
1212
  }
1213

    
1214
  return $variables;
1215
}
1216

    
1217
/**
1218
 * Returns a persistent variable.
1219
 *
1220
 * Case-sensitivity of the variable_* functions depends on the database
1221
 * collation used. To avoid problems, always use lower case for persistent
1222
 * variable names.
1223
 *
1224
 * @param $name
1225
 *   The name of the variable to return.
1226
 * @param $default
1227
 *   The default value to use if this variable has never been set.
1228
 *
1229
 * @return
1230
 *   The value of the variable. Unserialization is taken care of as necessary.
1231
 *
1232
 * @see variable_del()
1233
 * @see variable_set()
1234
 */
1235
function variable_get($name, $default = NULL) {
1236
  global $conf;
1237

    
1238
  return isset($conf[$name]) ? $conf[$name] : $default;
1239
}
1240

    
1241
/**
1242
 * Sets a persistent variable.
1243
 *
1244
 * Case-sensitivity of the variable_* functions depends on the database
1245
 * collation used. To avoid problems, always use lower case for persistent
1246
 * variable names.
1247
 *
1248
 * @param $name
1249
 *   The name of the variable to set.
1250
 * @param $value
1251
 *   The value to set. This can be any PHP data type; these functions take care
1252
 *   of serialization as necessary.
1253
 *
1254
 * @see variable_del()
1255
 * @see variable_get()
1256
 */
1257
function variable_set($name, $value) {
1258
  global $conf;
1259

    
1260
  db_merge('variable')->key(array('name' => $name))->fields(array('value' => serialize($value)))->execute();
1261

    
1262
  cache_clear_all('variables', 'cache_bootstrap');
1263

    
1264
  $conf[$name] = $value;
1265
}
1266

    
1267
/**
1268
 * Unsets a persistent variable.
1269
 *
1270
 * Case-sensitivity of the variable_* functions depends on the database
1271
 * collation used. To avoid problems, always use lower case for persistent
1272
 * variable names.
1273
 *
1274
 * @param $name
1275
 *   The name of the variable to undefine.
1276
 *
1277
 * @see variable_get()
1278
 * @see variable_set()
1279
 */
1280
function variable_del($name) {
1281
  global $conf;
1282

    
1283
  db_delete('variable')
1284
    ->condition('name', $name)
1285
    ->execute();
1286
  cache_clear_all('variables', 'cache_bootstrap');
1287

    
1288
  unset($conf[$name]);
1289
}
1290

    
1291
/**
1292
 * Retrieves the current page from the cache.
1293
 *
1294
 * Note: we do not serve cached pages to authenticated users, or to anonymous
1295
 * users when $_SESSION is non-empty. $_SESSION may contain status messages
1296
 * from a form submission, the contents of a shopping cart, or other user-
1297
 * specific content that should not be cached and displayed to other users.
1298
 *
1299
 * @param $check_only
1300
 *   (optional) Set to TRUE to only return whether a previous call found a
1301
 *   cache entry.
1302
 *
1303
 * @return
1304
 *   The cache object, if the page was found in the cache, NULL otherwise.
1305
 */
1306
function drupal_page_get_cache($check_only = FALSE) {
1307
  global $base_root;
1308
  static $cache_hit = FALSE;
1309

    
1310
  if ($check_only) {
1311
    return $cache_hit;
1312
  }
1313

    
1314
  if (drupal_page_is_cacheable()) {
1315
    $cache = cache_get($base_root . request_uri(), 'cache_page');
1316
    if ($cache !== FALSE) {
1317
      $cache_hit = TRUE;
1318
    }
1319
    return $cache;
1320
  }
1321
}
1322

    
1323
/**
1324
 * Determines the cacheability of the current page.
1325
 *
1326
 * @param $allow_caching
1327
 *   Set to FALSE if you want to prevent this page from being cached.
1328
 *
1329
 * @return
1330
 *   TRUE if the current page can be cached, FALSE otherwise.
1331
 */
1332
function drupal_page_is_cacheable($allow_caching = NULL) {
1333
  $allow_caching_static = &drupal_static(__FUNCTION__, TRUE);
1334
  if (isset($allow_caching)) {
1335
    $allow_caching_static = $allow_caching;
1336
  }
1337

    
1338
  return $allow_caching_static && ($_SERVER['REQUEST_METHOD'] == 'GET' || $_SERVER['REQUEST_METHOD'] == 'HEAD')
1339
    && !drupal_is_cli();
1340
}
1341

    
1342
/**
1343
 * Invokes a bootstrap hook in all bootstrap modules that implement it.
1344
 *
1345
 * @param $hook
1346
 *   The name of the bootstrap hook to invoke.
1347
 *
1348
 * @see bootstrap_hooks()
1349
 */
1350
function bootstrap_invoke_all($hook) {
1351
  // Bootstrap modules should have been loaded when this function is called, so
1352
  // we don't need to tell module_list() to reset its internal list (and we
1353
  // therefore leave the first parameter at its default value of FALSE). We
1354
  // still pass in TRUE for the second parameter, though; in case this is the
1355
  // first time during the bootstrap that module_list() is called, we want to
1356
  // make sure that its internal cache is primed with the bootstrap modules
1357
  // only.
1358
  foreach (module_list(FALSE, TRUE) as $module) {
1359
    drupal_load('module', $module);
1360
    module_invoke($module, $hook);
1361
  }
1362
}
1363

    
1364
/**
1365
 * Includes a file with the provided type and name.
1366
 *
1367
 * This prevents including a theme, engine, module, etc., more than once.
1368
 *
1369
 * @param $type
1370
 *   The type of item to load (i.e. theme, theme_engine, module).
1371
 * @param $name
1372
 *   The name of the item to load.
1373
 *
1374
 * @return
1375
 *   TRUE if the item is loaded or has already been loaded.
1376
 */
1377
function drupal_load($type, $name) {
1378
  // Once a file is included this can't be reversed during a request so do not
1379
  // use drupal_static() here.
1380
  static $files = array();
1381

    
1382
  if (isset($files[$type][$name])) {
1383
    return TRUE;
1384
  }
1385

    
1386
  $filename = drupal_get_filename($type, $name);
1387

    
1388
  if ($filename) {
1389
    include_once DRUPAL_ROOT . '/' . $filename;
1390
    $files[$type][$name] = TRUE;
1391

    
1392
    return TRUE;
1393
  }
1394

    
1395
  return FALSE;
1396
}
1397

    
1398
/**
1399
 * Sets an HTTP response header for the current page.
1400
 *
1401
 * Note: When sending a Content-Type header, always include a 'charset' type,
1402
 * too. This is necessary to avoid security bugs (e.g. UTF-7 XSS).
1403
 *
1404
 * @param $name
1405
 *   The HTTP header name, or the special 'Status' header name.
1406
 * @param $value
1407
 *   The HTTP header value; if equal to FALSE, the specified header is unset.
1408
 *   If $name is 'Status', this is expected to be a status code followed by a
1409
 *   reason phrase, e.g. "404 Not Found".
1410
 * @param $append
1411
 *   Whether to append the value to an existing header or to replace it.
1412
 */
1413
function drupal_add_http_header($name, $value, $append = FALSE) {
1414
  // The headers as name/value pairs.
1415
  $headers = &drupal_static('drupal_http_headers', array());
1416

    
1417
  $name_lower = strtolower($name);
1418
  _drupal_set_preferred_header_name($name);
1419

    
1420
  if ($value === FALSE) {
1421
    $headers[$name_lower] = FALSE;
1422
  }
1423
  elseif (isset($headers[$name_lower]) && $append) {
1424
    // Multiple headers with identical names may be combined using comma (RFC
1425
    // 2616, section 4.2).
1426
    $headers[$name_lower] .= ',' . $value;
1427
  }
1428
  else {
1429
    $headers[$name_lower] = $value;
1430
  }
1431
  drupal_send_headers(array($name => $headers[$name_lower]), TRUE);
1432
}
1433

    
1434
/**
1435
 * Gets the HTTP response headers for the current page.
1436
 *
1437
 * @param $name
1438
 *   An HTTP header name. If omitted, all headers are returned as name/value
1439
 *   pairs. If an array value is FALSE, the header has been unset.
1440
 *
1441
 * @return
1442
 *   A string containing the header value, or FALSE if the header has been set,
1443
 *   or NULL if the header has not been set.
1444
 */
1445
function drupal_get_http_header($name = NULL) {
1446
  $headers = &drupal_static('drupal_http_headers', array());
1447
  if (isset($name)) {
1448
    $name = strtolower($name);
1449
    return isset($headers[$name]) ? $headers[$name] : NULL;
1450
  }
1451
  else {
1452
    return $headers;
1453
  }
1454
}
1455

    
1456
/**
1457
 * Sets the preferred name for the HTTP header.
1458
 *
1459
 * Header names are case-insensitive, but for maximum compatibility they should
1460
 * follow "common form" (see RFC 2617, section 4.2).
1461
 */
1462
function _drupal_set_preferred_header_name($name = NULL) {
1463
  static $header_names = array();
1464

    
1465
  if (!isset($name)) {
1466
    return $header_names;
1467
  }
1468
  $header_names[strtolower($name)] = $name;
1469
}
1470

    
1471
/**
1472
 * Sends the HTTP response headers that were previously set, adding defaults.
1473
 *
1474
 * Headers are set in drupal_add_http_header(). Default headers are not set
1475
 * if they have been replaced or unset using drupal_add_http_header().
1476
 *
1477
 * @param array $default_headers
1478
 *   (optional) An array of headers as name/value pairs.
1479
 * @param bool $only_default
1480
 *   (optional) If TRUE and headers have already been sent, send only the
1481
 *   specified headers.
1482
 */
1483
function drupal_send_headers($default_headers = array(), $only_default = FALSE) {
1484
  $headers_sent = &drupal_static(__FUNCTION__, FALSE);
1485
  $headers = drupal_get_http_header();
1486
  if ($only_default && $headers_sent) {
1487
    $headers = array();
1488
  }
1489
  $headers_sent = TRUE;
1490

    
1491
  $header_names = _drupal_set_preferred_header_name();
1492
  foreach ($default_headers as $name => $value) {
1493
    $name_lower = strtolower($name);
1494
    if (!isset($headers[$name_lower])) {
1495
      $headers[$name_lower] = $value;
1496
      $header_names[$name_lower] = $name;
1497
    }
1498
  }
1499
  foreach ($headers as $name_lower => $value) {
1500
    if ($name_lower == 'status') {
1501
      header($_SERVER['SERVER_PROTOCOL'] . ' ' . $value);
1502
    }
1503
    // Skip headers that have been unset.
1504
    elseif ($value !== FALSE) {
1505
      header($header_names[$name_lower] . ': ' . $value);
1506
    }
1507
  }
1508
}
1509

    
1510
/**
1511
 * Sets HTTP headers in preparation for a page response.
1512
 *
1513
 * Authenticated users are always given a 'no-cache' header, and will fetch a
1514
 * fresh page on every request. This prevents authenticated users from seeing
1515
 * locally cached pages.
1516
 *
1517
 * ETag and Last-Modified headers are not set per default for authenticated
1518
 * users so that browsers do not send If-Modified-Since headers from
1519
 * authenticated user pages. drupal_serve_page_from_cache() will set appropriate
1520
 * ETag and Last-Modified headers for cached pages.
1521
 *
1522
 * @see drupal_page_set_cache()
1523
 */
1524
function drupal_page_header() {
1525
  $headers_sent = &drupal_static(__FUNCTION__, FALSE);
1526
  if ($headers_sent) {
1527
    return TRUE;
1528
  }
1529
  $headers_sent = TRUE;
1530

    
1531
  $default_headers = array(
1532
    'Expires' => 'Sun, 19 Nov 1978 05:00:00 GMT',
1533
    'Cache-Control' => 'no-cache, must-revalidate',
1534
    // Prevent browsers from sniffing a response and picking a MIME type
1535
    // different from the declared content-type, since that can lead to
1536
    // XSS and other vulnerabilities.
1537
    'X-Content-Type-Options' => 'nosniff',
1538
  );
1539
  drupal_send_headers($default_headers);
1540
}
1541

    
1542
/**
1543
 * Sets HTTP headers in preparation for a cached page response.
1544
 *
1545
 * The headers allow as much as possible in proxies and browsers without any
1546
 * particular knowledge about the pages. Modules can override these headers
1547
 * using drupal_add_http_header().
1548
 *
1549
 * If the request is conditional (using If-Modified-Since and If-None-Match),
1550
 * and the conditions match those currently in the cache, a 304 Not Modified
1551
 * response is sent.
1552
 */
1553
function drupal_serve_page_from_cache(stdClass $cache) {
1554
  // Negotiate whether to use compression.
1555
  $page_compression = !empty($cache->data['page_compressed']);
1556
  $return_compressed = $page_compression && isset($_SERVER['HTTP_ACCEPT_ENCODING']) && strpos($_SERVER['HTTP_ACCEPT_ENCODING'], 'gzip') !== FALSE;
1557

    
1558
  // Get headers set in hook_boot(). Keys are lower-case.
1559
  $hook_boot_headers = drupal_get_http_header();
1560

    
1561
  // Headers generated in this function, that may be replaced or unset using
1562
  // drupal_add_http_headers(). Keys are mixed-case.
1563
  $default_headers = array();
1564

    
1565
  foreach ($cache->data['headers'] as $name => $value) {
1566
    // In the case of a 304 response, certain headers must be sent, and the
1567
    // remaining may not (see RFC 2616, section 10.3.5). Do not override
1568
    // headers set in hook_boot().
1569
    $name_lower = strtolower($name);
1570
    if (in_array($name_lower, array('content-location', 'expires', 'cache-control', 'vary')) && !isset($hook_boot_headers[$name_lower])) {
1571
      drupal_add_http_header($name, $value);
1572
      unset($cache->data['headers'][$name]);
1573
    }
1574
  }
1575

    
1576
  // If the client sent a session cookie, a cached copy will only be served
1577
  // to that one particular client due to Vary: Cookie. Thus, do not set
1578
  // max-age > 0, allowing the page to be cached by external proxies, when a
1579
  // session cookie is present unless the Vary header has been replaced or
1580
  // unset in hook_boot().
1581
  $max_age = !isset($_COOKIE[session_name()]) || isset($hook_boot_headers['vary']) ? variable_get('page_cache_maximum_age', 0) : 0;
1582
  $default_headers['Cache-Control'] = 'public, max-age=' . $max_age;
1583

    
1584
  // Entity tag should change if the output changes.
1585
  $etag = '"' . $cache->created . '-' . intval($return_compressed) . '"';
1586
  header('Etag: ' . $etag);
1587

    
1588
  // See if the client has provided the required HTTP headers.
1589
  $if_modified_since = isset($_SERVER['HTTP_IF_MODIFIED_SINCE']) ? strtotime($_SERVER['HTTP_IF_MODIFIED_SINCE']) : FALSE;
1590
  $if_none_match = isset($_SERVER['HTTP_IF_NONE_MATCH']) ? stripslashes($_SERVER['HTTP_IF_NONE_MATCH']) : FALSE;
1591

    
1592
  if ($if_modified_since && $if_none_match
1593
      && $if_none_match == $etag // etag must match
1594
      && $if_modified_since == $cache->created) {  // if-modified-since must match
1595
    header($_SERVER['SERVER_PROTOCOL'] . ' 304 Not Modified');
1596
    drupal_send_headers($default_headers);
1597
    return;
1598
  }
1599

    
1600
  // Send the remaining headers.
1601
  foreach ($cache->data['headers'] as $name => $value) {
1602
    drupal_add_http_header($name, $value);
1603
  }
1604

    
1605
  $default_headers['Last-Modified'] = gmdate(DATE_RFC7231, $cache->created);
1606

    
1607
  // HTTP/1.0 proxies does not support the Vary header, so prevent any caching
1608
  // by sending an Expires date in the past. HTTP/1.1 clients ignores the
1609
  // Expires header if a Cache-Control: max-age= directive is specified (see RFC
1610
  // 2616, section 14.9.3).
1611
  $default_headers['Expires'] = 'Sun, 19 Nov 1978 05:00:00 GMT';
1612

    
1613
  drupal_send_headers($default_headers);
1614

    
1615
  // Allow HTTP proxies to cache pages for anonymous users without a session
1616
  // cookie. The Vary header is used to indicates the set of request-header
1617
  // fields that fully determines whether a cache is permitted to use the
1618
  // response to reply to a subsequent request for a given URL without
1619
  // revalidation. If a Vary header has been set in hook_boot(), it is assumed
1620
  // that the module knows how to cache the page.
1621
  if (!isset($hook_boot_headers['vary']) && !variable_get('omit_vary_cookie')) {
1622
    header('Vary: Cookie');
1623
  }
1624

    
1625
  if ($page_compression) {
1626
    header('Vary: Accept-Encoding', FALSE);
1627
    // If page_compression is enabled, the cache contains gzipped data.
1628
    if ($return_compressed) {
1629
      // $cache->data['body'] is already gzip'ed, so make sure
1630
      // zlib.output_compression does not compress it once more.
1631
      ini_set('zlib.output_compression', '0');
1632
      header('Content-Encoding: gzip');
1633
    }
1634
    else {
1635
      // The client does not support compression, so unzip the data in the
1636
      // cache. Strip the gzip header and run uncompress.
1637
      $cache->data['body'] = gzinflate(substr(substr($cache->data['body'], 10), 0, -8));
1638
    }
1639
  }
1640

    
1641
  // Print the page.
1642
  print $cache->data['body'];
1643
}
1644

    
1645
/**
1646
 * Defines the critical hooks that force modules to always be loaded.
1647
 */
1648
function bootstrap_hooks() {
1649
  return array('boot', 'exit', 'watchdog', 'language_init');
1650
}
1651

    
1652
/**
1653
 * Unserializes and appends elements from a serialized string.
1654
 *
1655
 * @param $obj
1656
 *   The object to which the elements are appended.
1657
 * @param $field
1658
 *   The attribute of $obj whose value should be unserialized.
1659
 */
1660
function drupal_unpack($obj, $field = 'data') {
1661
  if ($obj->$field && $data = unserialize($obj->$field)) {
1662
    foreach ($data as $key => $value) {
1663
      if (!empty($key) && !isset($obj->$key)) {
1664
        $obj->$key = $value;
1665
      }
1666
    }
1667
  }
1668
  return $obj;
1669
}
1670

    
1671
/**
1672
 * Translates a string to the current language or to a given language.
1673
 *
1674
 * The t() function serves two purposes. First, at run-time it translates
1675
 * user-visible text into the appropriate language. Second, various mechanisms
1676
 * that figure out what text needs to be translated work off t() -- the text
1677
 * inside t() calls is added to the database of strings to be translated.
1678
 * These strings are expected to be in English, so the first argument should
1679
 * always be in English. To enable a fully-translatable site, it is important
1680
 * that all human-readable text that will be displayed on the site or sent to
1681
 * a user is passed through the t() function, or a related function. See the
1682
 * @link http://drupal.org/node/322729 Localization API @endlink pages for
1683
 * more information, including recommendations on how to break up or not
1684
 * break up strings for translation.
1685
 *
1686
 * @section sec_translating_vars Translating Variables
1687
 * You should never use t() to translate variables, such as calling
1688
 * @code t($text); @endcode, unless the text that the variable holds has been
1689
 * passed through t() elsewhere (e.g., $text is one of several translated
1690
 * literal strings in an array). It is especially important never to call
1691
 * @code t($user_text); @endcode, where $user_text is some text that a user
1692
 * entered - doing that can lead to cross-site scripting and other security
1693
 * problems. However, you can use variable substitution in your string, to put
1694
 * variable text such as user names or link URLs into translated text. Variable
1695
 * substitution looks like this:
1696
 * @code
1697
 * $text = t("@name's blog", array('@name' => format_username($account)));
1698
 * @endcode
1699
 * Basically, you can put variables like @name into your string, and t() will
1700
 * substitute their sanitized values at translation time. (See the
1701
 * Localization API pages referenced above and the documentation of
1702
 * format_string() for details about how to define variables in your string.)
1703
 * Translators can then rearrange the string as necessary for the language
1704
 * (e.g., in Spanish, it might be "blog de @name").
1705
 *
1706
 * @section sec_alt_funcs_install Use During Installation Phase
1707
 * During the Drupal installation phase, some resources used by t() wil not be
1708
 * available to code that needs localization. See st() and get_t() for
1709
 * alternatives.
1710
 *
1711
 * @section sec_context String context
1712
 * Matching source strings are normally only translated once, and the same
1713
 * translation is used everywhere that has a matching string. However, in some
1714
 * cases, a certain English source string needs to have multiple translations.
1715
 * One example of this is the string "May", which could be used as either a
1716
 * full month name or a 3-letter abbreviated month. In other languages where
1717
 * the month name for May has more than 3 letters, you would need to provide
1718
 * two different translations (one for the full name and one abbreviated), and
1719
 * the correct form would need to be chosen, depending on how "May" is being
1720
 * used. To facilitate this, the "May" string should be provided with two
1721
 * different contexts in the $options parameter when calling t(). For example:
1722
 * @code
1723
 * t('May', array(), array('context' => 'Long month name')
1724
 * t('May', array(), array('context' => 'Abbreviated month name')
1725
 * @endcode
1726
 * See https://localize.drupal.org/node/2109 for more information.
1727
 *
1728
 * @param $string
1729
 *   A string containing the English string to translate.
1730
 * @param $args
1731
 *   An associative array of replacements to make after translation. Based
1732
 *   on the first character of the key, the value is escaped and/or themed.
1733
 *   See format_string() for details.
1734
 * @param $options
1735
 *   An associative array of additional options, with the following elements:
1736
 *   - 'langcode' (defaults to the current language): The language code to
1737
 *     translate to a language other than what is used to display the page.
1738
 *   - 'context' (defaults to the empty context): A string giving the context
1739
 *     that the source string belongs to. See @ref sec_context above for more
1740
 *     information.
1741
 *
1742
 * @return
1743
 *   The translated string.
1744
 *
1745
 * @see st()
1746
 * @see get_t()
1747
 * @see format_string()
1748
 * @ingroup sanitization
1749
 */
1750
function t($string, array $args = array(), array $options = array()) {
1751
  global $language;
1752
  static $custom_strings;
1753

    
1754
  // Merge in default.
1755
  if (empty($options['langcode'])) {
1756
    $options['langcode'] = isset($language->language) ? $language->language : 'en';
1757
  }
1758
  if (empty($options['context'])) {
1759
    $options['context'] = '';
1760
  }
1761

    
1762
  // First, check for an array of customized strings. If present, use the array
1763
  // *instead of* database lookups. This is a high performance way to provide a
1764
  // handful of string replacements. See settings.php for examples.
1765
  // Cache the $custom_strings variable to improve performance.
1766
  if (!isset($custom_strings[$options['langcode']])) {
1767
    $custom_strings[$options['langcode']] = variable_get('locale_custom_strings_' . $options['langcode'], array());
1768
  }
1769
  // Custom strings work for English too, even if locale module is disabled.
1770
  if (isset($custom_strings[$options['langcode']][$options['context']][$string])) {
1771
    $string = $custom_strings[$options['langcode']][$options['context']][$string];
1772
  }
1773
  // Translate with locale module if enabled.
1774
  elseif ($options['langcode'] != 'en' && function_exists('locale')) {
1775
    $string = locale($string, $options['context'], $options['langcode']);
1776
  }
1777
  if (empty($args)) {
1778
    return $string;
1779
  }
1780
  else {
1781
    return format_string($string, $args);
1782
  }
1783
}
1784

    
1785
/**
1786
 * Formats a string for HTML display by replacing variable placeholders.
1787
 *
1788
 * This function replaces variable placeholders in a string with the requested
1789
 * values and escapes the values so they can be safely displayed as HTML. It
1790
 * should be used on any unknown text that is intended to be printed to an HTML
1791
 * page (especially text that may have come from untrusted users, since in that
1792
 * case it prevents cross-site scripting and other security problems).
1793
 *
1794
 * In most cases, you should use t() rather than calling this function
1795
 * directly, since it will translate the text (on non-English-only sites) in
1796
 * addition to formatting it.
1797
 *
1798
 * @param $string
1799
 *   A string containing placeholders.
1800
 * @param $args
1801
 *   An associative array of replacements to make. Occurrences in $string of
1802
 *   any key in $args are replaced with the corresponding value, after optional
1803
 *   sanitization and formatting. The type of sanitization and formatting
1804
 *   depends on the first character of the key:
1805
 *   - @variable: Escaped to HTML using check_plain(). Use this as the default
1806
 *     choice for anything displayed on a page on the site.
1807
 *   - %variable: Escaped to HTML and formatted using drupal_placeholder(),
1808
 *     which makes it display as <em>emphasized</em> text.
1809
 *   - !variable: Inserted as is, with no sanitization or formatting. Only use
1810
 *     this for text that has already been prepared for HTML display (for
1811
 *     example, user-supplied text that has already been run through
1812
 *     check_plain() previously, or is expected to contain some limited HTML
1813
 *     tags and has already been run through filter_xss() previously).
1814
 *
1815
 * @see t()
1816
 * @ingroup sanitization
1817
 */
1818
function format_string($string, array $args = array()) {
1819
  // Transform arguments before inserting them.
1820
  foreach ($args as $key => $value) {
1821
    switch ($key[0]) {
1822
      case '@':
1823
        // Escaped only.
1824
        $args[$key] = check_plain($value);
1825
        break;
1826

    
1827
      case '%':
1828
      default:
1829
        // Escaped and placeholder.
1830
        $args[$key] = drupal_placeholder($value);
1831
        break;
1832

    
1833
      case '!':
1834
        // Pass-through.
1835
    }
1836
  }
1837
  return strtr($string, $args);
1838
}
1839

    
1840
/**
1841
 * Encodes special characters in a plain-text string for display as HTML.
1842
 *
1843
 * Also validates strings as UTF-8 to prevent cross site scripting attacks on
1844
 * Internet Explorer 6.
1845
 *
1846
 * @param string $text
1847
 *   The text to be checked or processed.
1848
 *
1849
 * @return string
1850
 *   An HTML safe version of $text. If $text is not valid UTF-8, an empty string
1851
 *   is returned and, on PHP < 5.4, a warning may be issued depending on server
1852
 *   configuration (see @link https://bugs.php.net/bug.php?id=47494 @endlink).
1853
 *
1854
 * @see drupal_validate_utf8()
1855
 * @ingroup sanitization
1856
 */
1857
function check_plain($text) {
1858
  return htmlspecialchars($text, ENT_QUOTES, 'UTF-8');
1859
}
1860

    
1861
/**
1862
 * Checks whether a string is valid UTF-8.
1863
 *
1864
 * All functions designed to filter input should use drupal_validate_utf8
1865
 * to ensure they operate on valid UTF-8 strings to prevent bypass of the
1866
 * filter.
1867
 *
1868
 * When text containing an invalid UTF-8 lead byte (0xC0 - 0xFF) is presented
1869
 * as UTF-8 to Internet Explorer 6, the program may misinterpret subsequent
1870
 * bytes. When these subsequent bytes are HTML control characters such as
1871
 * quotes or angle brackets, parts of the text that were deemed safe by filters
1872
 * end up in locations that are potentially unsafe; An onerror attribute that
1873
 * is outside of a tag, and thus deemed safe by a filter, can be interpreted
1874
 * by the browser as if it were inside the tag.
1875
 *
1876
 * The function does not return FALSE for strings containing character codes
1877
 * above U+10FFFF, even though these are prohibited by RFC 3629.
1878
 *
1879
 * @param $text
1880
 *   The text to check.
1881
 *
1882
 * @return
1883
 *   TRUE if the text is valid UTF-8, FALSE if not.
1884
 */
1885
function drupal_validate_utf8($text) {
1886
  if (strlen($text) == 0) {
1887
    return TRUE;
1888
  }
1889
  // With the PCRE_UTF8 modifier 'u', preg_match() fails silently on strings
1890
  // containing invalid UTF-8 byte sequences. It does not reject character
1891
  // codes above U+10FFFF (represented by 4 or more octets), though.
1892
  return (preg_match('/^./us', $text) == 1);
1893
}
1894

    
1895
/**
1896
 * Returns the equivalent of Apache's $_SERVER['REQUEST_URI'] variable.
1897
 *
1898
 * Because $_SERVER['REQUEST_URI'] is only available on Apache, we generate an
1899
 * equivalent using other environment variables.
1900
 */
1901
function request_uri() {
1902
  if (isset($_SERVER['REQUEST_URI'])) {
1903
    $uri = $_SERVER['REQUEST_URI'];
1904
  }
1905
  else {
1906
    if (isset($_SERVER['argv'])) {
1907
      $uri = $_SERVER['SCRIPT_NAME'] . '?' . $_SERVER['argv'][0];
1908
    }
1909
    elseif (isset($_SERVER['QUERY_STRING'])) {
1910
      $uri = $_SERVER['SCRIPT_NAME'] . '?' . $_SERVER['QUERY_STRING'];
1911
    }
1912
    else {
1913
      $uri = $_SERVER['SCRIPT_NAME'];
1914
    }
1915
  }
1916
  // Prevent multiple slashes to avoid cross site requests via the Form API.
1917
  $uri = '/' . ltrim($uri, '/');
1918

    
1919
  return $uri;
1920
}
1921

    
1922
/**
1923
 * Logs an exception.
1924
 *
1925
 * This is a wrapper function for watchdog() which automatically decodes an
1926
 * exception.
1927
 *
1928
 * @param $type
1929
 *   The category to which this message belongs.
1930
 * @param $exception
1931
 *   The exception that is going to be logged.
1932
 * @param $message
1933
 *   The message to store in the log. If empty, a text that contains all useful
1934
 *   information about the passed-in exception is used.
1935
 * @param $variables
1936
 *   Array of variables to replace in the message on display. Defaults to the
1937
 *   return value of _drupal_decode_exception().
1938
 * @param $severity
1939
 *   The severity of the message, as per RFC 3164.
1940
 * @param $link
1941
 *   A link to associate with the message.
1942
 *
1943
 * @see watchdog()
1944
 * @see _drupal_decode_exception()
1945
 */
1946
function watchdog_exception($type, Exception $exception, $message = NULL, $variables = array(), $severity = WATCHDOG_ERROR, $link = NULL) {
1947

    
1948
   // Use a default value if $message is not set.
1949
   if (empty($message)) {
1950
     // The exception message is run through check_plain() by _drupal_decode_exception().
1951
     $message = '%type: !message in %function (line %line of %file).';
1952
   }
1953
   // $variables must be an array so that we can add the exception information.
1954
   if (!is_array($variables)) {
1955
     $variables = array();
1956
   }
1957

    
1958
   require_once DRUPAL_ROOT . '/includes/errors.inc';
1959
   $variables += _drupal_decode_exception($exception);
1960
   watchdog($type, $message, $variables, $severity, $link);
1961
}
1962

    
1963
/**
1964
 * Logs a system message.
1965
 *
1966
 * @param $type
1967
 *   The category to which this message belongs. Can be any string, but the
1968
 *   general practice is to use the name of the module calling watchdog().
1969
 * @param $message
1970
 *   The message to store in the log. Keep $message translatable
1971
 *   by not concatenating dynamic values into it! Variables in the
1972
 *   message should be added by using placeholder strings alongside
1973
 *   the variables argument to declare the value of the placeholders.
1974
 *   See t() for documentation on how $message and $variables interact.
1975
 * @param $variables
1976
 *   Array of variables to replace in the message on display or
1977
 *   NULL if message is already translated or not possible to
1978
 *   translate.
1979
 * @param $severity
1980
 *   The severity of the message; one of the following values as defined in
1981
 *   @link http://www.faqs.org/rfcs/rfc3164.html RFC 3164: @endlink
1982
 *   - WATCHDOG_EMERGENCY: Emergency, system is unusable.
1983
 *   - WATCHDOG_ALERT: Alert, action must be taken immediately.
1984
 *   - WATCHDOG_CRITICAL: Critical conditions.
1985
 *   - WATCHDOG_ERROR: Error conditions.
1986
 *   - WATCHDOG_WARNING: Warning conditions.
1987
 *   - WATCHDOG_NOTICE: (default) Normal but significant conditions.
1988
 *   - WATCHDOG_INFO: Informational messages.
1989
 *   - WATCHDOG_DEBUG: Debug-level messages.
1990
 * @param $link
1991
 *   A link to associate with the message.
1992
 *
1993
 * @see watchdog_severity_levels()
1994
 * @see hook_watchdog()
1995
 */
1996
function watchdog($type, $message, $variables = array(), $severity = WATCHDOG_NOTICE, $link = NULL) {
1997
  global $user, $base_root;
1998

    
1999
  static $in_error_state = FALSE;
2000

    
2001
  // It is possible that the error handling will itself trigger an error. In that case, we could
2002
  // end up in an infinite loop. To avoid that, we implement a simple static semaphore.
2003
  if (!$in_error_state && function_exists('module_invoke_all')) {
2004
    $in_error_state = TRUE;
2005

    
2006
    // The user object may not exist in all conditions, so 0 is substituted if needed.
2007
    $user_uid = isset($user->uid) ? $user->uid : 0;
2008

    
2009
    // Prepare the fields to be logged
2010
    $log_entry = array(
2011
      'type'        => $type,
2012
      'message'     => $message,
2013
      'variables'   => $variables,
2014
      'severity'    => $severity,
2015
      'link'        => $link,
2016
      'user'        => $user,
2017
      'uid'         => $user_uid,
2018
      'request_uri' => $base_root . request_uri(),
2019
      'referer'     => isset($_SERVER['HTTP_REFERER']) ? $_SERVER['HTTP_REFERER'] : '',
2020
      'ip'          => ip_address(),
2021
      // Request time isn't accurate for long processes, use time() instead.
2022
      'timestamp'   => time(),
2023
    );
2024

    
2025
    // Call the logging hooks to log/process the message
2026
    module_invoke_all('watchdog', $log_entry);
2027

    
2028
    // It is critical that the semaphore is only cleared here, in the parent
2029
    // watchdog() call (not outside the loop), to prevent recursive execution.
2030
    $in_error_state = FALSE;
2031
  }
2032
}
2033

    
2034
/**
2035
 * Sets a message to display to the user.
2036
 *
2037
 * Messages are stored in a session variable and displayed in page.tpl.php via
2038
 * the $messages theme variable.
2039
 *
2040
 * Example usage:
2041
 * @code
2042
 * drupal_set_message(t('An error occurred and processing did not complete.'), 'error');
2043
 * @endcode
2044
 *
2045
 * @param string $message
2046
 *   (optional) The translated message to be displayed to the user. For
2047
 *   consistency with other messages, it should begin with a capital letter and
2048
 *   end with a period.
2049
 * @param string $type
2050
 *   (optional) The message's type. Defaults to 'status'. These values are
2051
 *   supported:
2052
 *   - 'status'
2053
 *   - 'warning'
2054
 *   - 'error'
2055
 * @param bool $repeat
2056
 *   (optional) If this is FALSE and the message is already set, then the
2057
 *   message won't be repeated. Defaults to TRUE.
2058
 *
2059
 * @return array|null
2060
 *   A multidimensional array with keys corresponding to the set message types.
2061
 *   The indexed array values of each contain the set messages for that type.
2062
 *   Or, if there are no messages set, the function returns NULL.
2063
 *
2064
 * @see drupal_get_messages()
2065
 * @see theme_status_messages()
2066
 */
2067
function drupal_set_message($message = NULL, $type = 'status', $repeat = TRUE) {
2068
  if ($message || $message === '0' || $message === 0) {
2069
    if (!isset($_SESSION['messages'][$type])) {
2070
      $_SESSION['messages'][$type] = array();
2071
    }
2072

    
2073
    if ($repeat || !in_array($message, $_SESSION['messages'][$type])) {
2074
      $_SESSION['messages'][$type][] = $message;
2075
    }
2076

    
2077
    // Mark this page as being uncacheable.
2078
    drupal_page_is_cacheable(FALSE);
2079
  }
2080

    
2081
  // Messages not set when DB connection fails.
2082
  return isset($_SESSION['messages']) ? $_SESSION['messages'] : NULL;
2083
}
2084

    
2085
/**
2086
 * Returns all messages that have been set with drupal_set_message().
2087
 *
2088
 * @param string $type
2089
 *   (optional) Limit the messages returned by type. Defaults to NULL, meaning
2090
 *   all types. These values are supported:
2091
 *   - NULL
2092
 *   - 'status'
2093
 *   - 'warning'
2094
 *   - 'error'
2095
 * @param bool $clear_queue
2096
 *   (optional) If this is TRUE, the queue will be cleared of messages of the
2097
 *   type specified in the $type parameter. Otherwise the queue will be left
2098
 *   intact. Defaults to TRUE.
2099
 *
2100
 * @return array
2101
 *   A multidimensional array with keys corresponding to the set message types.
2102
 *   The indexed array values of each contain the set messages for that type.
2103
 *   The messages returned are limited to the type specified in the $type
2104
 *   parameter. If there are no messages of the specified type, an empty array
2105
 *   is returned.
2106
 *
2107
 * @see drupal_set_message()
2108
 * @see theme_status_messages()
2109
 */
2110
function drupal_get_messages($type = NULL, $clear_queue = TRUE) {
2111
  if ($messages = drupal_set_message()) {
2112
    if ($type) {
2113
      if ($clear_queue) {
2114
        unset($_SESSION['messages'][$type]);
2115
      }
2116
      if (isset($messages[$type])) {
2117
        return array($type => $messages[$type]);
2118
      }
2119
    }
2120
    else {
2121
      if ($clear_queue) {
2122
        unset($_SESSION['messages']);
2123
      }
2124
      return $messages;
2125
    }
2126
  }
2127
  return array();
2128
}
2129

    
2130
/**
2131
 * Gets the title of the current page.
2132
 *
2133
 * The title is displayed on the page and in the title bar.
2134
 *
2135
 * @return
2136
 *   The current page's title.
2137
 */
2138
function drupal_get_title() {
2139
  $title = drupal_set_title();
2140

    
2141
  // During a bootstrap, menu.inc is not included and thus we cannot provide a title.
2142
  if (!isset($title) && function_exists('menu_get_active_title')) {
2143
    $title = check_plain(menu_get_active_title());
2144
  }
2145

    
2146
  return $title;
2147
}
2148

    
2149
/**
2150
 * Sets the title of the current page.
2151
 *
2152
 * The title is displayed on the page and in the title bar.
2153
 *
2154
 * @param $title
2155
 *   Optional string value to assign to the page title; or if set to NULL
2156
 *   (default), leaves the current title unchanged.
2157
 * @param $output
2158
 *   Optional flag - normally should be left as CHECK_PLAIN. Only set to
2159
 *   PASS_THROUGH if you have already removed any possibly dangerous code
2160
 *   from $title using a function like check_plain() or filter_xss(). With this
2161
 *   flag the string will be passed through unchanged.
2162
 *
2163
 * @return
2164
 *   The updated title of the current page.
2165
 */
2166
function drupal_set_title($title = NULL, $output = CHECK_PLAIN) {
2167
  $stored_title = &drupal_static(__FUNCTION__);
2168

    
2169
  if (isset($title)) {
2170
    $stored_title = ($output == PASS_THROUGH) ? $title : check_plain($title);
2171
  }
2172

    
2173
  return $stored_title;
2174
}
2175

    
2176
/**
2177
 * Checks to see if an IP address has been blocked.
2178
 *
2179
 * Blocked IP addresses are stored in the database by default. However for
2180
 * performance reasons we allow an override in settings.php. This allows us
2181
 * to avoid querying the database at this critical stage of the bootstrap if
2182
 * an administrative interface for IP address blocking is not required.
2183
 *
2184
 * @param $ip
2185
 *   IP address to check.
2186
 *
2187
 * @return bool
2188
 *   TRUE if access is denied, FALSE if access is allowed.
2189
 */
2190
function drupal_is_denied($ip) {
2191
  // Because this function is called on every page request, we first check
2192
  // for an array of IP addresses in settings.php before querying the
2193
  // database.
2194
  $blocked_ips = variable_get('blocked_ips');
2195
  $denied = FALSE;
2196
  if (isset($blocked_ips) && is_array($blocked_ips)) {
2197
    $denied = in_array($ip, $blocked_ips);
2198
  }
2199
  // Only check if database.inc is loaded already. If
2200
  // $conf['page_cache_without_database'] = TRUE; is set in settings.php,
2201
  // then the database won't be loaded here so the IPs in the database
2202
  // won't be denied. However the user asked explicitly not to use the
2203
  // database and also in this case it's quite likely that the user relies
2204
  // on higher performance solutions like a firewall.
2205
  elseif (class_exists('Database', FALSE)) {
2206
    $denied = (bool)db_query("SELECT 1 FROM {blocked_ips} WHERE ip = :ip", array(':ip' => $ip))->fetchField();
2207
  }
2208
  return $denied;
2209
}
2210

    
2211
/**
2212
 * Handles denied users.
2213
 *
2214
 * @param $ip
2215
 *   IP address to check. Prints a message and exits if access is denied.
2216
 */
2217
function drupal_block_denied($ip) {
2218
  // Deny access to blocked IP addresses - t() is not yet available.
2219
  if (drupal_is_denied($ip)) {
2220
    header($_SERVER['SERVER_PROTOCOL'] . ' 403 Forbidden');
2221
    print 'Sorry, ' . check_plain(ip_address()) . ' has been banned.';
2222
    exit();
2223
  }
2224
}
2225

    
2226
/**
2227
 * Returns a URL-safe, base64 encoded string of highly randomized bytes (over the full 8-bit range).
2228
 *
2229
 * @param $byte_count
2230
 *   The number of random bytes to fetch and base64 encode.
2231
 *
2232
 * @return string
2233
 *   The base64 encoded result will have a length of up to 4 * $byte_count.
2234
 */
2235
function drupal_random_key($byte_count = 32) {
2236
  return drupal_base64_encode(drupal_random_bytes($byte_count));
2237
}
2238

    
2239
/**
2240
 * Returns a URL-safe, base64 encoded version of the supplied string.
2241
 *
2242
 * @param $string
2243
 *   The string to convert to base64.
2244
 *
2245
 * @return string
2246
 */
2247
function drupal_base64_encode($string) {
2248
  $data = base64_encode($string);
2249
  // Modify the output so it's safe to use in URLs.
2250
  return strtr($data, array('+' => '-', '/' => '_', '=' => ''));
2251
}
2252

    
2253
/**
2254
 * Returns a string of highly randomized bytes (over the full 8-bit range).
2255
 *
2256
 * This function is better than simply calling mt_rand() or any other built-in
2257
 * PHP function because it can return a long string of bytes (compared to < 4
2258
 * bytes normally from mt_rand()) and uses the best available pseudo-random
2259
 * source.
2260
 *
2261
 * @param $count
2262
 *   The number of characters (bytes) to return in the string.
2263
 */
2264
function drupal_random_bytes($count)  {
2265
  // $random_state does not use drupal_static as it stores random bytes.
2266
  static $random_state, $bytes, $has_openssl;
2267

    
2268
  $missing_bytes = $count - strlen($bytes);
2269

    
2270
  if ($missing_bytes > 0) {
2271
    // PHP versions prior 5.3.4 experienced openssl_random_pseudo_bytes()
2272
    // locking on Windows and rendered it unusable.
2273
    if (!isset($has_openssl)) {
2274
      $has_openssl = version_compare(PHP_VERSION, '5.3.4', '>=') && function_exists('openssl_random_pseudo_bytes');
2275
    }
2276

    
2277
    // openssl_random_pseudo_bytes() will find entropy in a system-dependent
2278
    // way.
2279
    if ($has_openssl) {
2280
      $bytes .= openssl_random_pseudo_bytes($missing_bytes);
2281
    }
2282

    
2283
    // Else, read directly from /dev/urandom, which is available on many *nix
2284
    // systems and is considered cryptographically secure.
2285
    elseif ($fh = @fopen('/dev/urandom', 'rb')) {
2286
      // PHP only performs buffered reads, so in reality it will always read
2287
      // at least 4096 bytes. Thus, it costs nothing extra to read and store
2288
      // that much so as to speed any additional invocations.
2289
      $bytes .= fread($fh, max(4096, $missing_bytes));
2290
      fclose($fh);
2291
    }
2292

    
2293
    // If we couldn't get enough entropy, this simple hash-based PRNG will
2294
    // generate a good set of pseudo-random bytes on any system.
2295
    // Note that it may be important that our $random_state is passed
2296
    // through hash() prior to being rolled into $output, that the two hash()
2297
    // invocations are different, and that the extra input into the first one -
2298
    // the microtime() - is prepended rather than appended. This is to avoid
2299
    // directly leaking $random_state via the $output stream, which could
2300
    // allow for trivial prediction of further "random" numbers.
2301
    if (strlen($bytes) < $count) {
2302
      // Initialize on the first call. The contents of $_SERVER includes a mix of
2303
      // user-specific and system information that varies a little with each page.
2304
      if (!isset($random_state)) {
2305
        $random_state = print_r($_SERVER, TRUE);
2306
        if (function_exists('getmypid')) {
2307
          // Further initialize with the somewhat random PHP process ID.
2308
          $random_state .= getmypid();
2309
        }
2310
        $bytes = '';
2311
      }
2312

    
2313
      do {
2314
        $random_state = hash('sha256', microtime() . mt_rand() . $random_state);
2315
        $bytes .= hash('sha256', mt_rand() . $random_state, TRUE);
2316
      }
2317
      while (strlen($bytes) < $count);
2318
    }
2319
  }
2320
  $output = substr($bytes, 0, $count);
2321
  $bytes = substr($bytes, $count);
2322
  return $output;
2323
}
2324

    
2325
/**
2326
 * Calculates a base-64 encoded, URL-safe sha-256 hmac.
2327
 *
2328
 * @param string $data
2329
 *   String to be validated with the hmac.
2330
 * @param string $key
2331
 *   A secret string key.
2332
 *
2333
 * @return string
2334
 *   A base-64 encoded sha-256 hmac, with + replaced with -, / with _ and
2335
 *   any = padding characters removed.
2336
 */
2337
function drupal_hmac_base64($data, $key) {
2338
  // Casting $data and $key to strings here is necessary to avoid empty string
2339
  // results of the hash function if they are not scalar values. As this
2340
  // function is used in security-critical contexts like token validation it is
2341
  // important that it never returns an empty string.
2342
  $hmac = base64_encode(hash_hmac('sha256', (string) $data, (string) $key, TRUE));
2343
  // Modify the hmac so it's safe to use in URLs.
2344
  return strtr($hmac, array('+' => '-', '/' => '_', '=' => ''));
2345
}
2346

    
2347
/**
2348
 * Calculates a base-64 encoded, URL-safe sha-256 hash.
2349
 *
2350
 * @param $data
2351
 *   String to be hashed.
2352
 *
2353
 * @return
2354
 *   A base-64 encoded sha-256 hash, with + replaced with -, / with _ and
2355
 *   any = padding characters removed.
2356
 */
2357
function drupal_hash_base64($data) {
2358
  $hash = base64_encode(hash('sha256', $data, TRUE));
2359
  // Modify the hash so it's safe to use in URLs.
2360
  return strtr($hash, array('+' => '-', '/' => '_', '=' => ''));
2361
}
2362

    
2363
/**
2364
 * Merges multiple arrays, recursively, and returns the merged array.
2365
 *
2366
 * This function is similar to PHP's array_merge_recursive() function, but it
2367
 * handles non-array values differently. When merging values that are not both
2368
 * arrays, the latter value replaces the former rather than merging with it.
2369
 *
2370
 * Example:
2371
 * @code
2372
 * $link_options_1 = array('fragment' => 'x', 'attributes' => array('title' => t('X'), 'class' => array('a', 'b')));
2373
 * $link_options_2 = array('fragment' => 'y', 'attributes' => array('title' => t('Y'), 'class' => array('c', 'd')));
2374
 *
2375
 * // This results in array('fragment' => array('x', 'y'), 'attributes' => array('title' => array(t('X'), t('Y')), 'class' => array('a', 'b', 'c', 'd'))).
2376
 * $incorrect = array_merge_recursive($link_options_1, $link_options_2);
2377
 *
2378
 * // This results in array('fragment' => 'y', 'attributes' => array('title' => t('Y'), 'class' => array('a', 'b', 'c', 'd'))).
2379
 * $correct = drupal_array_merge_deep($link_options_1, $link_options_2);
2380
 * @endcode
2381
 *
2382
 * @param ...
2383
 *   Arrays to merge.
2384
 *
2385
 * @return
2386
 *   The merged array.
2387
 *
2388
 * @see drupal_array_merge_deep_array()
2389
 */
2390
function drupal_array_merge_deep() {
2391
  $args = func_get_args();
2392
  return drupal_array_merge_deep_array($args);
2393
}
2394

    
2395
/**
2396
 * Merges multiple arrays, recursively, and returns the merged array.
2397
 *
2398
 * This function is equivalent to drupal_array_merge_deep(), except the
2399
 * input arrays are passed as a single array parameter rather than a variable
2400
 * parameter list.
2401
 *
2402
 * The following are equivalent:
2403
 * - drupal_array_merge_deep($a, $b);
2404
 * - drupal_array_merge_deep_array(array($a, $b));
2405
 *
2406
 * The following are also equivalent:
2407
 * - call_user_func_array('drupal_array_merge_deep', $arrays_to_merge);
2408
 * - drupal_array_merge_deep_array($arrays_to_merge);
2409
 *
2410
 * @see drupal_array_merge_deep()
2411
 */
2412
function drupal_array_merge_deep_array($arrays) {
2413
  $result = array();
2414

    
2415
  foreach ($arrays as $array) {
2416
    foreach ($array as $key => $value) {
2417
      // Renumber integer keys as array_merge_recursive() does. Note that PHP
2418
      // automatically converts array keys that are integer strings (e.g., '1')
2419
      // to integers.
2420
      if (is_integer($key)) {
2421
        $result[] = $value;
2422
      }
2423
      // Recurse when both values are arrays.
2424
      elseif (isset($result[$key]) && is_array($result[$key]) && is_array($value)) {
2425
        $result[$key] = drupal_array_merge_deep_array(array($result[$key], $value));
2426
      }
2427
      // Otherwise, use the latter value, overriding any previous value.
2428
      else {
2429
        $result[$key] = $value;
2430
      }
2431
    }
2432
  }
2433

    
2434
  return $result;
2435
}
2436

    
2437
/**
2438
 * Generates a default anonymous $user object.
2439
 *
2440
 * @return Object - the user object.
2441
 */
2442
function drupal_anonymous_user() {
2443
  $user = variable_get('drupal_anonymous_user_object', new stdClass);
2444
  $user->uid = 0;
2445
  $user->hostname = ip_address();
2446
  $user->roles = array();
2447
  $user->roles[DRUPAL_ANONYMOUS_RID] = 'anonymous user';
2448
  $user->cache = 0;
2449
  return $user;
2450
}
2451

    
2452
/**
2453
 * Ensures Drupal is bootstrapped to the specified phase.
2454
 *
2455
 * In order to bootstrap Drupal from another PHP script, you can use this code:
2456
 * @code
2457
 *   define('DRUPAL_ROOT', '/path/to/drupal');
2458
 *   require_once DRUPAL_ROOT . '/includes/bootstrap.inc';
2459
 *   drupal_bootstrap(DRUPAL_BOOTSTRAP_FULL);
2460
 * @endcode
2461
 *
2462
 * @param int $phase
2463
 *   A constant telling which phase to bootstrap to. When you bootstrap to a
2464
 *   particular phase, all earlier phases are run automatically. Possible
2465
 *   values:
2466
 *   - DRUPAL_BOOTSTRAP_CONFIGURATION: Initializes configuration.
2467
 *   - DRUPAL_BOOTSTRAP_PAGE_CACHE: Tries to serve a cached page.
2468
 *   - DRUPAL_BOOTSTRAP_DATABASE: Initializes the database layer.
2469
 *   - DRUPAL_BOOTSTRAP_VARIABLES: Initializes the variable system.
2470
 *   - DRUPAL_BOOTSTRAP_SESSION: Initializes session handling.
2471
 *   - DRUPAL_BOOTSTRAP_PAGE_HEADER: Sets up the page header.
2472
 *   - DRUPAL_BOOTSTRAP_LANGUAGE: Finds out the language of the page.
2473
 *   - DRUPAL_BOOTSTRAP_FULL: Fully loads Drupal. Validates and fixes input
2474
 *     data.
2475
 * @param boolean $new_phase
2476
 *   A boolean, set to FALSE if calling drupal_bootstrap from inside a
2477
 *   function called from drupal_bootstrap (recursion).
2478
 *
2479
 * @return int
2480
 *   The most recently completed phase.
2481
 */
2482
function drupal_bootstrap($phase = NULL, $new_phase = TRUE) {
2483
  // Not drupal_static(), because does not depend on any run-time information.
2484
  static $phases = array(
2485
    DRUPAL_BOOTSTRAP_CONFIGURATION,
2486
    DRUPAL_BOOTSTRAP_PAGE_CACHE,
2487
    DRUPAL_BOOTSTRAP_DATABASE,
2488
    DRUPAL_BOOTSTRAP_VARIABLES,
2489
    DRUPAL_BOOTSTRAP_SESSION,
2490
    DRUPAL_BOOTSTRAP_PAGE_HEADER,
2491
    DRUPAL_BOOTSTRAP_LANGUAGE,
2492
    DRUPAL_BOOTSTRAP_FULL,
2493
  );
2494
  // Not drupal_static(), because the only legitimate API to control this is to
2495
  // call drupal_bootstrap() with a new phase parameter.
2496
  static $final_phase;
2497
  // Not drupal_static(), because it's impossible to roll back to an earlier
2498
  // bootstrap state.
2499
  static $stored_phase = -1;
2500

    
2501
  if (isset($phase)) {
2502
    // When not recursing, store the phase name so it's not forgotten while
2503
    // recursing but take care of not going backwards.
2504
    if ($new_phase && $phase >= $stored_phase) {
2505
      $final_phase = $phase;
2506
    }
2507

    
2508
    // Call a phase if it has not been called before and is below the requested
2509
    // phase.
2510
    while ($phases && $phase > $stored_phase && $final_phase > $stored_phase) {
2511
      $current_phase = array_shift($phases);
2512

    
2513
      // This function is re-entrant. Only update the completed phase when the
2514
      // current call actually resulted in a progress in the bootstrap process.
2515
      if ($current_phase > $stored_phase) {
2516
        $stored_phase = $current_phase;
2517
      }
2518

    
2519
      switch ($current_phase) {
2520
        case DRUPAL_BOOTSTRAP_CONFIGURATION:
2521
          require_once DRUPAL_ROOT . '/includes/request-sanitizer.inc';
2522
          _drupal_bootstrap_configuration();
2523
          break;
2524

    
2525
        case DRUPAL_BOOTSTRAP_PAGE_CACHE:
2526
          _drupal_bootstrap_page_cache();
2527
          break;
2528

    
2529
        case DRUPAL_BOOTSTRAP_DATABASE:
2530
          _drupal_bootstrap_database();
2531
          break;
2532

    
2533
        case DRUPAL_BOOTSTRAP_VARIABLES:
2534
          _drupal_bootstrap_variables();
2535
          break;
2536

    
2537
        case DRUPAL_BOOTSTRAP_SESSION:
2538
          require_once DRUPAL_ROOT . '/' . variable_get('session_inc', 'includes/session.inc');
2539
          drupal_session_initialize();
2540
          break;
2541

    
2542
        case DRUPAL_BOOTSTRAP_PAGE_HEADER:
2543
          _drupal_bootstrap_page_header();
2544
          break;
2545

    
2546
        case DRUPAL_BOOTSTRAP_LANGUAGE:
2547
          drupal_language_initialize();
2548
          break;
2549

    
2550
        case DRUPAL_BOOTSTRAP_FULL:
2551
          require_once DRUPAL_ROOT . '/includes/common.inc';
2552
          _drupal_bootstrap_full();
2553
          break;
2554
      }
2555
    }
2556
  }
2557
  return $stored_phase;
2558
}
2559

    
2560
/**
2561
 * Returns the time zone of the current user.
2562
 */
2563
function drupal_get_user_timezone() {
2564
  global $user;
2565
  if (variable_get('configurable_timezones', 1) && $user->uid && $user->timezone) {
2566
    return $user->timezone;
2567
  }
2568
  else {
2569
    // Ignore PHP strict notice if time zone has not yet been set in the php.ini
2570
    // configuration.
2571
    return variable_get('date_default_timezone', @date_default_timezone_get());
2572
  }
2573
}
2574

    
2575
/**
2576
 * Gets a salt useful for hardening against SQL injection.
2577
 *
2578
 * @return
2579
 *   A salt based on information in settings.php, not in the database.
2580
 */
2581
function drupal_get_hash_salt() {
2582
  global $drupal_hash_salt, $databases;
2583
  // If the $drupal_hash_salt variable is empty, a hash of the serialized
2584
  // database credentials is used as a fallback salt.
2585
  return empty($drupal_hash_salt) ? hash('sha256', serialize($databases)) : $drupal_hash_salt;
2586
}
2587

    
2588
/**
2589
 * Provides custom PHP error handling.
2590
 *
2591
 * @param $error_level
2592
 *   The level of the error raised.
2593
 * @param $message
2594
 *   The error message.
2595
 * @param $filename
2596
 *   The filename that the error was raised in.
2597
 * @param $line
2598
 *   The line number the error was raised at.
2599
 * @param $context
2600
 *   An array that points to the active symbol table at the point the error
2601
 *   occurred.
2602
 */
2603
function _drupal_error_handler($error_level, $message, $filename, $line, $context) {
2604
  require_once DRUPAL_ROOT . '/includes/errors.inc';
2605
  _drupal_error_handler_real($error_level, $message, $filename, $line, $context);
2606
}
2607

    
2608
/**
2609
 * Provides custom PHP exception handling.
2610
 *
2611
 * Uncaught exceptions are those not enclosed in a try/catch block. They are
2612
 * always fatal: the execution of the script will stop as soon as the exception
2613
 * handler exits.
2614
 *
2615
 * @param $exception
2616
 *   The exception object that was thrown.
2617
 */
2618
function _drupal_exception_handler($exception) {
2619
  require_once DRUPAL_ROOT . '/includes/errors.inc';
2620

    
2621
  try {
2622
    // Log the message to the watchdog and return an error page to the user.
2623
    _drupal_log_error(_drupal_decode_exception($exception), TRUE);
2624
  }
2625
  catch (Exception $exception2) {
2626
    // Add a 500 status code in case an exception was thrown before the 500
2627
    // status could be set (e.g. while loading a maintenance theme from cache).
2628
    drupal_add_http_header('Status', '500 Internal Server Error');
2629

    
2630
    // Another uncaught exception was thrown while handling the first one.
2631
    // If we are displaying errors, then do so with no possibility of a further uncaught exception being thrown.
2632
    if (error_displayable()) {
2633
      print '<h1>Additional uncaught exception thrown while handling exception.</h1>';
2634
      print '<h2>Original</h2><p>' . _drupal_render_exception_safe($exception) . '</p>';
2635
      print '<h2>Additional</h2><p>' . _drupal_render_exception_safe($exception2) . '</p><hr />';
2636
    }
2637
  }
2638
}
2639

    
2640
/**
2641
 * Sets up the script environment and loads settings.php.
2642
 */
2643
function _drupal_bootstrap_configuration() {
2644
  // Set the Drupal custom error handler.
2645
  set_error_handler('_drupal_error_handler');
2646
  set_exception_handler('_drupal_exception_handler');
2647

    
2648
  drupal_environment_initialize();
2649
  // Start a page timer:
2650
  timer_start('page');
2651
  // Initialize the configuration, including variables from settings.php.
2652
  drupal_settings_initialize();
2653

    
2654
  // Sanitize unsafe keys from the request.
2655
  DrupalRequestSanitizer::sanitize();
2656
}
2657

    
2658
/**
2659
 * Attempts to serve a page from the cache.
2660
 */
2661
function _drupal_bootstrap_page_cache() {
2662
  global $user;
2663

    
2664
  // Allow specifying special cache handlers in settings.php, like
2665
  // using memcached or files for storing cache information.
2666
  require_once DRUPAL_ROOT . '/includes/cache.inc';
2667
  foreach (variable_get('cache_backends', array()) as $include) {
2668
    require_once DRUPAL_ROOT . '/' . $include;
2669
  }
2670
  // Check for a cache mode force from settings.php.
2671
  if (variable_get('page_cache_without_database')) {
2672
    $cache_enabled = TRUE;
2673
  }
2674
  else {
2675
    drupal_bootstrap(DRUPAL_BOOTSTRAP_VARIABLES, FALSE);
2676
    $cache_enabled = variable_get('cache');
2677
  }
2678
  drupal_block_denied(ip_address());
2679
  // If there is no session cookie and cache is enabled (or forced), try
2680
  // to serve a cached page.
2681
  if (!isset($_COOKIE[session_name()]) && $cache_enabled) {
2682
    // Make sure there is a user object because its timestamp will be
2683
    // checked, hook_boot might check for anonymous user etc.
2684
    $user = drupal_anonymous_user();
2685
    // Get the page from the cache.
2686
    $cache = drupal_page_get_cache();
2687
    // If there is a cached page, display it.
2688
    if (is_object($cache)) {
2689
      header('X-Drupal-Cache: HIT');
2690
      // Restore the metadata cached with the page.
2691
      $_GET['q'] = $cache->data['path'];
2692
      drupal_set_title($cache->data['title'], PASS_THROUGH);
2693
      date_default_timezone_set(drupal_get_user_timezone());
2694
      // If the skipping of the bootstrap hooks is not enforced, call
2695
      // hook_boot.
2696
      if (variable_get('page_cache_invoke_hooks', TRUE)) {
2697
        bootstrap_invoke_all('boot');
2698
      }
2699
      drupal_serve_page_from_cache($cache);
2700
      // If the skipping of the bootstrap hooks is not enforced, call
2701
      // hook_exit.
2702
      if (variable_get('page_cache_invoke_hooks', TRUE)) {
2703
        bootstrap_invoke_all('exit');
2704
      }
2705
      // We are done.
2706
      exit;
2707
    }
2708
    else {
2709
      header('X-Drupal-Cache: MISS');
2710
    }
2711
  }
2712
}
2713

    
2714
/**
2715
 * Initializes the database system and registers autoload functions.
2716
 */
2717
function _drupal_bootstrap_database() {
2718
  // Redirect the user to the installation script if Drupal has not been
2719
  // installed yet (i.e., if no $databases array has been defined in the
2720
  // settings.php file) and we are not already installing.
2721
  if (empty($GLOBALS['databases']) && !drupal_installation_attempted()) {
2722
    include_once DRUPAL_ROOT . '/includes/install.inc';
2723
    install_goto('install.php');
2724
  }
2725

    
2726
  // The user agent header is used to pass a database prefix in the request when
2727
  // running tests. However, for security reasons, it is imperative that we
2728
  // validate we ourselves made the request.
2729
  if ($test_prefix = drupal_valid_test_ua()) {
2730
    // Set the test run id for use in other parts of Drupal.
2731
    $test_info = &$GLOBALS['drupal_test_info'];
2732
    $test_info['test_run_id'] = $test_prefix;
2733
    $test_info['in_child_site'] = TRUE;
2734

    
2735
    foreach ($GLOBALS['databases']['default'] as &$value) {
2736
      // Extract the current default database prefix.
2737
      if (!isset($value['prefix'])) {
2738
        $current_prefix = '';
2739
      }
2740
      elseif (is_array($value['prefix'])) {
2741
        $current_prefix = $value['prefix']['default'];
2742
      }
2743
      else {
2744
        $current_prefix = $value['prefix'];
2745
      }
2746

    
2747
      // Remove the current database prefix and replace it by our own.
2748
      $value['prefix'] = array(
2749
        'default' => $current_prefix . $test_prefix,
2750
      );
2751
    }
2752
  }
2753

    
2754
  // Initialize the database system. Note that the connection
2755
  // won't be initialized until it is actually requested.
2756
  require_once DRUPAL_ROOT . '/includes/database/database.inc';
2757

    
2758
  // Register autoload functions so that we can access classes and interfaces.
2759
  // The database autoload routine comes first so that we can load the database
2760
  // system without hitting the database. That is especially important during
2761
  // the install or upgrade process.
2762
  spl_autoload_register('drupal_autoload_class');
2763
  spl_autoload_register('drupal_autoload_interface');
2764
  if (version_compare(PHP_VERSION, '5.4') >= 0) {
2765
    spl_autoload_register('drupal_autoload_trait');
2766
  }
2767
}
2768

    
2769
/**
2770
 * Loads system variables and all enabled bootstrap modules.
2771
 */
2772
function _drupal_bootstrap_variables() {
2773
  global $conf;
2774

    
2775
  // Initialize the lock system.
2776
  require_once DRUPAL_ROOT . '/' . variable_get('lock_inc', 'includes/lock.inc');
2777
  lock_initialize();
2778

    
2779
  // Load variables from the database, but do not overwrite variables set in settings.php.
2780
  $conf = variable_initialize(isset($conf) ? $conf : array());
2781
  // Load bootstrap modules.
2782
  require_once DRUPAL_ROOT . '/includes/module.inc';
2783
  module_load_all(TRUE);
2784

    
2785
  // Sanitize the destination parameter (which is often used for redirects) to
2786
  // prevent open redirect attacks leading to other domains. Sanitize both
2787
  // $_GET['destination'] and $_REQUEST['destination'] to protect code that
2788
  // relies on either, but do not sanitize $_POST to avoid interfering with
2789
  // unrelated form submissions. The sanitization happens here because
2790
  // url_is_external() requires the variable system to be available.
2791
  if (isset($_GET['destination']) || isset($_REQUEST['destination'])) {
2792
    require_once DRUPAL_ROOT . '/includes/common.inc';
2793
    // If the destination is an external URL, remove it.
2794
    if (isset($_GET['destination']) && url_is_external($_GET['destination'])) {
2795
      unset($_GET['destination']);
2796
      unset($_REQUEST['destination']);
2797
    }
2798
    // Use the DrupalRequestSanitizer to ensure that the destination's query
2799
    // parameters are not dangerous.
2800
    if (isset($_GET['destination'])) {
2801
      DrupalRequestSanitizer::cleanDestination();
2802
    }
2803
    // If there's still something in $_REQUEST['destination'] that didn't come
2804
    // from $_GET, check it too.
2805
    if (isset($_REQUEST['destination']) && (!isset($_GET['destination']) || $_REQUEST['destination'] != $_GET['destination']) && url_is_external($_REQUEST['destination'])) {
2806
      unset($_REQUEST['destination']);
2807
    }
2808
  }
2809
}
2810

    
2811
/**
2812
 * Invokes hook_boot(), initializes locking system, and sends HTTP headers.
2813
 */
2814
function _drupal_bootstrap_page_header() {
2815
  bootstrap_invoke_all('boot');
2816

    
2817
  if (!drupal_is_cli()) {
2818
    ob_start();
2819
    drupal_page_header();
2820
  }
2821
}
2822

    
2823
/**
2824
 * Returns the current bootstrap phase for this Drupal process.
2825
 *
2826
 * The current phase is the one most recently completed by drupal_bootstrap().
2827
 *
2828
 * @see drupal_bootstrap()
2829
 */
2830
function drupal_get_bootstrap_phase() {
2831
  return drupal_bootstrap(NULL, FALSE);
2832
}
2833

    
2834
/**
2835
 * Returns the test prefix if this is an internal request from SimpleTest.
2836
 *
2837
 * @return
2838
 *   Either the simpletest prefix (the string "simpletest" followed by any
2839
 *   number of digits) or FALSE if the user agent does not contain a valid
2840
 *   HMAC and timestamp.
2841
 */
2842
function drupal_valid_test_ua() {
2843
  // No reason to reset this.
2844
  static $test_prefix;
2845

    
2846
  if (isset($test_prefix)) {
2847
    return $test_prefix;
2848
  }
2849

    
2850
  if (isset($_SERVER['HTTP_USER_AGENT']) && preg_match("/^(simpletest\d+);(.+);(.+);(.+)$/", $_SERVER['HTTP_USER_AGENT'], $matches)) {
2851
    list(, $prefix, $time, $salt, $hmac) = $matches;
2852
    $check_string =  $prefix . ';' . $time . ';' . $salt;
2853
    // We use the salt from settings.php to make the HMAC key, since
2854
    // the database is not yet initialized and we can't access any Drupal variables.
2855
    // The file properties add more entropy not easily accessible to others.
2856
    $key = drupal_get_hash_salt() . filectime(__FILE__) . fileinode(__FILE__);
2857
    $time_diff = REQUEST_TIME - $time;
2858
    // Since we are making a local request a 5 second time window is allowed,
2859
    // and the HMAC must match.
2860
    if ($time_diff >= 0 && $time_diff <= 5 && $hmac == drupal_hmac_base64($check_string, $key)) {
2861
      $test_prefix = $prefix;
2862
      return $test_prefix;
2863
    }
2864
  }
2865

    
2866
  $test_prefix = FALSE;
2867
  return $test_prefix;
2868
}
2869

    
2870
/**
2871
 * Generates a user agent string with a HMAC and timestamp for simpletest.
2872
 */
2873
function drupal_generate_test_ua($prefix) {
2874
  static $key;
2875

    
2876
  if (!isset($key)) {
2877
    // We use the salt from settings.php to make the HMAC key, since
2878
    // the database is not yet initialized and we can't access any Drupal variables.
2879
    // The file properties add more entropy not easily accessible to others.
2880
    $key = drupal_get_hash_salt() . filectime(__FILE__) . fileinode(__FILE__);
2881
  }
2882
  // Generate a moderately secure HMAC based on the database credentials.
2883
  $salt = uniqid('', TRUE);
2884
  $check_string = $prefix . ';' . time() . ';' . $salt;
2885
  return $check_string . ';' . drupal_hmac_base64($check_string, $key);
2886
}
2887

    
2888
/**
2889
 * Enables use of the theme system without requiring database access.
2890
 *
2891
 * Loads and initializes the theme system for site installs, updates and when
2892
 * the site is in maintenance mode. This also applies when the database fails.
2893
 *
2894
 * @see _drupal_maintenance_theme()
2895
 */
2896
function drupal_maintenance_theme() {
2897
  require_once DRUPAL_ROOT . '/includes/theme.maintenance.inc';
2898
  _drupal_maintenance_theme();
2899
}
2900

    
2901
/**
2902
 * Returns a simple 404 Not Found page.
2903
 *
2904
 * If fast 404 pages are enabled, and this is a matching page then print a
2905
 * simple 404 page and exit.
2906
 *
2907
 * This function is called from drupal_deliver_html_page() at the time when a
2908
 * a normal 404 page is generated, but it can also optionally be called directly
2909
 * from settings.php to prevent a Drupal bootstrap on these pages. See
2910
 * documentation in settings.php for the benefits and drawbacks of using this.
2911
 *
2912
 * Paths to dynamically-generated content, such as image styles, should also be
2913
 * accounted for in this function.
2914
 */
2915
function drupal_fast_404() {
2916
  $exclude_paths = variable_get('404_fast_paths_exclude', FALSE);
2917
  if ($exclude_paths && !preg_match($exclude_paths, $_GET['q'])) {
2918
    $fast_paths = variable_get('404_fast_paths', FALSE);
2919
    if ($fast_paths && preg_match($fast_paths, $_GET['q'])) {
2920
      drupal_add_http_header('Status', '404 Not Found');
2921
      $fast_404_html = variable_get('404_fast_html', '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>');
2922
      // Replace @path in the variable with the page path.
2923
      print strtr($fast_404_html, array('@path' => check_plain(request_uri())));
2924
      exit;
2925
    }
2926
  }
2927
}
2928

    
2929
/**
2930
 * Returns TRUE if a Drupal installation is currently being attempted.
2931
 */
2932
function drupal_installation_attempted() {
2933
  return defined('MAINTENANCE_MODE') && MAINTENANCE_MODE == 'install';
2934
}
2935

    
2936
/**
2937
 * Returns the name of the proper localization function.
2938
 *
2939
 * get_t() exists to support localization for code that might run during
2940
 * the installation phase, when some elements of the system might not have
2941
 * loaded.
2942
 *
2943
 * This would include implementations of hook_install(), which could run
2944
 * during the Drupal installation phase, and might also be run during
2945
 * non-installation time, such as while installing the module from the
2946
 * module administration page.
2947
 *
2948
 * Example usage:
2949
 * @code
2950
 *   $t = get_t();
2951
 *   $translated = $t('translate this');
2952
 * @endcode
2953
 *
2954
 * Use t() if your code will never run during the Drupal installation phase.
2955
 * Use st() if your code will only run during installation and never any other
2956
 * time. Use get_t() if your code could run in either circumstance.
2957
 *
2958
 * @see t()
2959
 * @see st()
2960
 * @ingroup sanitization
2961
 */
2962
function get_t() {
2963
  static $t;
2964
  // This is not converted to drupal_static because there is no point in
2965
  // resetting this as it can not change in the course of a request.
2966
  if (!isset($t)) {
2967
    $t = drupal_installation_attempted() ? 'st' : 't';
2968
  }
2969
  return $t;
2970
}
2971

    
2972
/**
2973
 * Initializes all the defined language types.
2974
 */
2975
function drupal_language_initialize() {
2976
  $types = language_types();
2977

    
2978
  // Ensure the language is correctly returned, even without multilanguage
2979
  // support. Also make sure we have a $language fallback, in case a language
2980
  // negotiation callback needs to do a full bootstrap.
2981
  // Useful for eg. XML/HTML 'lang' attributes.
2982
  $default = language_default();
2983
  foreach ($types as $type) {
2984
    $GLOBALS[$type] = $default;
2985
  }
2986
  if (drupal_multilingual()) {
2987
    include_once DRUPAL_ROOT . '/includes/language.inc';
2988
    foreach ($types as $type) {
2989
      $GLOBALS[$type] = language_initialize($type);
2990
    }
2991
    // Allow modules to react on language system initialization in multilingual
2992
    // environments.
2993
    bootstrap_invoke_all('language_init');
2994
  }
2995
}
2996

    
2997
/**
2998
 * Returns a list of the built-in language types.
2999
 *
3000
 * @return
3001
 *   An array of key-values pairs where the key is the language type and the
3002
 *   value is its configurability.
3003
 */
3004
function drupal_language_types() {
3005
  return array(
3006
    LANGUAGE_TYPE_INTERFACE => TRUE,
3007
    LANGUAGE_TYPE_CONTENT => FALSE,
3008
    LANGUAGE_TYPE_URL => FALSE,
3009
  );
3010
}
3011

    
3012
/**
3013
 * Returns TRUE if there is more than one language enabled.
3014
 *
3015
 * @return
3016
 *   TRUE if more than one language is enabled.
3017
 */
3018
function drupal_multilingual() {
3019
  // The "language_count" variable stores the number of enabled languages to
3020
  // avoid unnecessarily querying the database when building the list of
3021
  // enabled languages on monolingual sites.
3022
  return variable_get('language_count', 1) > 1;
3023
}
3024

    
3025
/**
3026
 * Returns an array of the available language types.
3027
 *
3028
 * @return
3029
 *   An array of all language types where the keys of each are the language type
3030
 *   name and its value is its configurability (TRUE/FALSE).
3031
 */
3032
function language_types() {
3033
  return array_keys(variable_get('language_types', drupal_language_types()));
3034
}
3035

    
3036
/**
3037
 * Returns a list of installed languages, indexed by the specified key.
3038
 *
3039
 * @param $field
3040
 *   (optional) The field to index the list with.
3041
 *
3042
 * @return
3043
 *   An associative array, keyed on the values of $field.
3044
 *   - If $field is 'weight' or 'enabled', the array is nested, with the outer
3045
 *     array's values each being associative arrays with language codes as
3046
 *     keys and language objects as values.
3047
 *   - For all other values of $field, the array is only one level deep, and
3048
 *     the array's values are language objects.
3049
 */
3050
function language_list($field = 'language') {
3051
  $languages = &drupal_static(__FUNCTION__);
3052
  // Init language list
3053
  if (!isset($languages)) {
3054
    if (drupal_multilingual() || module_exists('locale')) {
3055
      $languages['language'] = db_query('SELECT * FROM {languages} ORDER BY weight ASC, name ASC')->fetchAllAssoc('language');
3056
      // Users cannot uninstall the native English language. However, we allow
3057
      // it to be hidden from the installed languages. Therefore, at least one
3058
      // other language must be enabled then.
3059
      if (!$languages['language']['en']->enabled && !variable_get('language_native_enabled', TRUE)) {
3060
        unset($languages['language']['en']);
3061
      }
3062
    }
3063
    else {
3064
      // No locale module, so use the default language only.
3065
      $default = language_default();
3066
      $languages['language'][$default->language] = $default;
3067
    }
3068
  }
3069

    
3070
  // Return the array indexed by the right field
3071
  if (!isset($languages[$field])) {
3072
    $languages[$field] = array();
3073
    foreach ($languages['language'] as $lang) {
3074
      // Some values should be collected into an array
3075
      if (in_array($field, array('enabled', 'weight'))) {
3076
        $languages[$field][$lang->$field][$lang->language] = $lang;
3077
      }
3078
      else {
3079
        $languages[$field][$lang->$field] = $lang;
3080
      }
3081
    }
3082
  }
3083
  return $languages[$field];
3084
}
3085

    
3086
/**
3087
 * Returns the default language, as an object, or one of its properties.
3088
 *
3089
 * @param $property
3090
 *   (optional) The property of the language object to return.
3091
 *
3092
 * @return
3093
 *   Either the language object for the default language used on the site,
3094
 *   or the property of that object named in the $property parameter.
3095
 */
3096
function language_default($property = NULL) {
3097
  $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' => ''));
3098
  return $property ? $language->$property : $language;
3099
}
3100

    
3101
/**
3102
 * Returns the requested URL path of the page being viewed.
3103
 *
3104
 * Examples:
3105
 * - http://example.com/node/306 returns "node/306".
3106
 * - http://example.com/drupalfolder/node/306 returns "node/306" while
3107
 *   base_path() returns "/drupalfolder/".
3108
 * - http://example.com/path/alias (which is a path alias for node/306) returns
3109
 *   "path/alias" as opposed to the internal path.
3110
 * - http://example.com/index.php returns an empty string (meaning: front page).
3111
 * - http://example.com/index.php?page=1 returns an empty string.
3112
 *
3113
 * @return
3114
 *   The requested Drupal URL path.
3115
 *
3116
 * @see current_path()
3117
 */
3118
function request_path() {
3119
  static $path;
3120

    
3121
  if (isset($path)) {
3122
    return $path;
3123
  }
3124

    
3125
  if (isset($_GET['q']) && is_string($_GET['q'])) {
3126
    // This is a request with a ?q=foo/bar query string. $_GET['q'] is
3127
    // overwritten in drupal_path_initialize(), but request_path() is called
3128
    // very early in the bootstrap process, so the original value is saved in
3129
    // $path and returned in later calls.
3130
    $path = $_GET['q'];
3131
  }
3132
  elseif (isset($_SERVER['REQUEST_URI'])) {
3133
    // This request is either a clean URL, or 'index.php', or nonsense.
3134
    // Extract the path from REQUEST_URI.
3135
    $request_path = strtok($_SERVER['REQUEST_URI'], '?');
3136
    $base_path_len = strlen(rtrim(dirname($_SERVER['SCRIPT_NAME']), '\/'));
3137
    // Unescape and strip $base_path prefix, leaving q without a leading slash.
3138
    $path = substr(urldecode($request_path), $base_path_len + 1);
3139
    // If the path equals the script filename, either because 'index.php' was
3140
    // explicitly provided in the URL, or because the server added it to
3141
    // $_SERVER['REQUEST_URI'] even when it wasn't provided in the URL (some
3142
    // versions of Microsoft IIS do this), the front page should be served.
3143
    if ($path == basename($_SERVER['PHP_SELF'])) {
3144
      $path = '';
3145
    }
3146
  }
3147
  else {
3148
    // This is the front page.
3149
    $path = '';
3150
  }
3151

    
3152
  // Under certain conditions Apache's RewriteRule directive prepends the value
3153
  // assigned to $_GET['q'] with a slash. Moreover we can always have a trailing
3154
  // slash in place, hence we need to normalize $_GET['q'].
3155
  $path = trim($path, '/');
3156

    
3157
  return $path;
3158
}
3159

    
3160
/**
3161
 * Returns a component of the current Drupal path.
3162
 *
3163
 * When viewing a page at the path "admin/structure/types", for example, arg(0)
3164
 * returns "admin", arg(1) returns "structure", and arg(2) returns "types".
3165
 *
3166
 * Avoid use of this function where possible, as resulting code is hard to
3167
 * read. In menu callback functions, attempt to use named arguments. See the
3168
 * explanation in menu.inc for how to construct callbacks that take arguments.
3169
 * When attempting to use this function to load an element from the current
3170
 * path, e.g. loading the node on a node page, use menu_get_object() instead.
3171
 *
3172
 * @param $index
3173
 *   The index of the component, where each component is separated by a '/'
3174
 *   (forward-slash), and where the first component has an index of 0 (zero).
3175
 * @param $path
3176
 *   A path to break into components. Defaults to the path of the current page.
3177
 *
3178
 * @return
3179
 *   The component specified by $index, or NULL if the specified component was
3180
 *   not found. If called without arguments, it returns an array containing all
3181
 *   the components of the current path.
3182
 */
3183
function arg($index = NULL, $path = NULL) {
3184
  // Even though $arguments doesn't need to be resettable for any functional
3185
  // reasons (the result of explode() does not depend on any run-time
3186
  // information), it should be resettable anyway in case a module needs to
3187
  // free up the memory used by it.
3188
  // Use the advanced drupal_static() pattern, since this is called very often.
3189
  static $drupal_static_fast;
3190
  if (!isset($drupal_static_fast)) {
3191
    $drupal_static_fast['arguments'] = &drupal_static(__FUNCTION__);
3192
  }
3193
  $arguments = &$drupal_static_fast['arguments'];
3194

    
3195
  if (!isset($path)) {
3196
    $path = $_GET['q'];
3197
  }
3198
  if (!isset($arguments[$path])) {
3199
    $arguments[$path] = explode('/', $path);
3200
  }
3201
  if (!isset($index)) {
3202
    return $arguments[$path];
3203
  }
3204
  if (isset($arguments[$path][$index])) {
3205
    return $arguments[$path][$index];
3206
  }
3207
}
3208

    
3209
/**
3210
 * Returns the IP address of the client machine.
3211
 *
3212
 * If Drupal is behind a reverse proxy, we use the X-Forwarded-For header
3213
 * instead of $_SERVER['REMOTE_ADDR'], which would be the IP address of
3214
 * the proxy server, and not the client's. The actual header name can be
3215
 * configured by the reverse_proxy_header variable.
3216
 *
3217
 * @return
3218
 *   IP address of client machine, adjusted for reverse proxy and/or cluster
3219
 *   environments.
3220
 */
3221
function ip_address() {
3222
  $ip_address = &drupal_static(__FUNCTION__);
3223

    
3224
  if (!isset($ip_address)) {
3225
    $ip_address = $_SERVER['REMOTE_ADDR'];
3226

    
3227
    if (variable_get('reverse_proxy', 0)) {
3228
      $reverse_proxy_header = variable_get('reverse_proxy_header', 'HTTP_X_FORWARDED_FOR');
3229
      if (!empty($_SERVER[$reverse_proxy_header])) {
3230
        // If an array of known reverse proxy IPs is provided, then trust
3231
        // the XFF header if request really comes from one of them.
3232
        $reverse_proxy_addresses = variable_get('reverse_proxy_addresses', array());
3233

    
3234
        // Turn XFF header into an array.
3235
        $forwarded = explode(',', $_SERVER[$reverse_proxy_header]);
3236

    
3237
        // Trim the forwarded IPs; they may have been delimited by commas and spaces.
3238
        $forwarded = array_map('trim', $forwarded);
3239

    
3240
        // Tack direct client IP onto end of forwarded array.
3241
        $forwarded[] = $ip_address;
3242

    
3243
        // Eliminate all trusted IPs.
3244
        $untrusted = array_diff($forwarded, $reverse_proxy_addresses);
3245

    
3246
        if (!empty($untrusted)) {
3247
          // The right-most IP is the most specific we can trust.
3248
          $ip_address = array_pop($untrusted);
3249
        }
3250
        else {
3251
          // All IP addresses in the forwarded array are configured proxy IPs
3252
          // (and thus trusted). We take the leftmost IP.
3253
          $ip_address = array_shift($forwarded);
3254
        }
3255
      }
3256
    }
3257
  }
3258

    
3259
  return $ip_address;
3260
}
3261

    
3262
/**
3263
 * @addtogroup schemaapi
3264
 * @{
3265
 */
3266

    
3267
/**
3268
 * Gets the schema definition of a table, or the whole database schema.
3269
 *
3270
 * The returned schema will include any modifications made by any
3271
 * module that implements hook_schema_alter(). To get the schema without
3272
 * modifications, use drupal_get_schema_unprocessed().
3273
 *
3274
 *
3275
 * @param $table
3276
 *   The name of the table. If not given, the schema of all tables is returned.
3277
 * @param $rebuild
3278
 *   If true, the schema will be rebuilt instead of retrieved from the cache.
3279
 */
3280
function drupal_get_schema($table = NULL, $rebuild = FALSE) {
3281
  static $schema;
3282

    
3283
  if ($rebuild || !isset($table)) {
3284
    $schema = drupal_get_complete_schema($rebuild);
3285
  }
3286
  elseif (!isset($schema)) {
3287
    $schema = new SchemaCache();
3288
  }
3289

    
3290
  if (!isset($table)) {
3291
    return $schema;
3292
  }
3293
  if (isset($schema[$table])) {
3294
    return $schema[$table];
3295
  }
3296
  else {
3297
    return FALSE;
3298
  }
3299
}
3300

    
3301
/**
3302
 * Extends DrupalCacheArray to allow for dynamic building of the schema cache.
3303
 */
3304
class SchemaCache extends DrupalCacheArray {
3305

    
3306
  /**
3307
   * Constructs a SchemaCache object.
3308
   */
3309
  public function __construct() {
3310
    // Cache by request method.
3311
    parent::__construct('schema:runtime:' . ($_SERVER['REQUEST_METHOD'] == 'GET'), 'cache');
3312
  }
3313

    
3314
  /**
3315
   * Overrides DrupalCacheArray::resolveCacheMiss().
3316
   */
3317
  protected function resolveCacheMiss($offset) {
3318
    $complete_schema = drupal_get_complete_schema();
3319
    $value = isset($complete_schema[$offset]) ? $complete_schema[$offset] :  NULL;
3320
    $this->storage[$offset] = $value;
3321
    $this->persist($offset);
3322
    return $value;
3323
  }
3324
}
3325

    
3326
/**
3327
 * Gets the whole database schema.
3328
 *
3329
 * The returned schema will include any modifications made by any
3330
 * module that implements hook_schema_alter().
3331
 *
3332
 * @param $rebuild
3333
 *   If true, the schema will be rebuilt instead of retrieved from the cache.
3334
 */
3335
function drupal_get_complete_schema($rebuild = FALSE) {
3336
  static $schema = array();
3337

    
3338
  if (empty($schema) || $rebuild) {
3339
    // Try to load the schema from cache.
3340
    if (!$rebuild && $cached = cache_get('schema')) {
3341
      $schema = $cached->data;
3342
    }
3343
    // Otherwise, rebuild the schema cache.
3344
    else {
3345
      $schema = array();
3346
      // Load the .install files to get hook_schema.
3347
      // On some databases this function may be called before bootstrap has
3348
      // been completed, so we force the functions we need to load just in case.
3349
      if (function_exists('module_load_all_includes')) {
3350
        // This function can be called very early in the bootstrap process, so
3351
        // we force the module_list() cache to be refreshed to ensure that it
3352
        // contains the complete list of modules before we go on to call
3353
        // module_load_all_includes().
3354
        module_list(TRUE);
3355
        module_load_all_includes('install');
3356
      }
3357

    
3358
      require_once DRUPAL_ROOT . '/includes/common.inc';
3359
      // Invoke hook_schema for all modules.
3360
      foreach (module_implements('schema') as $module) {
3361
        // Cast the result of hook_schema() to an array, as a NULL return value
3362
        // would cause array_merge() to set the $schema variable to NULL as well.
3363
        // That would break modules which use $schema further down the line.
3364
        $current = (array) module_invoke($module, 'schema');
3365
        // Set 'module' and 'name' keys for each table, and remove descriptions,
3366
        // as they needlessly slow down cache_get() for every single request.
3367
        _drupal_schema_initialize($current, $module);
3368
        $schema = array_merge($schema, $current);
3369
      }
3370

    
3371
      drupal_alter('schema', $schema);
3372
      // If the schema is empty, avoid saving it: some database engines require
3373
      // the schema to perform queries, and this could lead to infinite loops.
3374
      if (!empty($schema) && (drupal_get_bootstrap_phase() == DRUPAL_BOOTSTRAP_FULL)) {
3375
        cache_set('schema', $schema);
3376
      }
3377
      if ($rebuild) {
3378
        cache_clear_all('schema:', 'cache', TRUE);
3379
      }
3380
    }
3381
  }
3382

    
3383
  return $schema;
3384
}
3385

    
3386
/**
3387
 * @} End of "addtogroup schemaapi".
3388
 */
3389

    
3390

    
3391
/**
3392
 * @addtogroup registry
3393
 * @{
3394
 */
3395

    
3396
/**
3397
 * Confirms that an interface is available.
3398
 *
3399
 * This function is rarely called directly. Instead, it is registered as an
3400
 * spl_autoload()  handler, and PHP calls it for us when necessary.
3401
 *
3402
 * @param $interface
3403
 *   The name of the interface to check or load.
3404
 *
3405
 * @return
3406
 *   TRUE if the interface is currently available, FALSE otherwise.
3407
 */
3408
function drupal_autoload_interface($interface) {
3409
  return _registry_check_code('interface', $interface);
3410
}
3411

    
3412
/**
3413
 * Confirms that a class is available.
3414
 *
3415
 * This function is rarely called directly. Instead, it is registered as an
3416
 * spl_autoload()  handler, and PHP calls it for us when necessary.
3417
 *
3418
 * @param $class
3419
 *   The name of the class to check or load.
3420
 *
3421
 * @return
3422
 *   TRUE if the class is currently available, FALSE otherwise.
3423
 */
3424
function drupal_autoload_class($class) {
3425
  return _registry_check_code('class', $class);
3426
}
3427

    
3428
/**
3429
 * Confirms that a trait is available.
3430
 *
3431
 * This function is rarely called directly. Instead, it is registered as an
3432
 * spl_autoload() handler, and PHP calls it for us when necessary.
3433
 *
3434
 * @param string $trait
3435
 *   The name of the trait to check or load.
3436
 *
3437
 * @return bool
3438
 *   TRUE if the trait is currently available, FALSE otherwise.
3439
 */
3440
function drupal_autoload_trait($trait) {
3441
  return _registry_check_code('trait', $trait);
3442
}
3443

    
3444
/**
3445
 * Checks for a resource in the registry.
3446
 *
3447
 * @param $type
3448
 *   The type of resource we are looking up, or one of the constants
3449
 *   REGISTRY_RESET_LOOKUP_CACHE or REGISTRY_WRITE_LOOKUP_CACHE, which
3450
 *   signal that we should reset or write the cache, respectively.
3451
 * @param $name
3452
 *   The name of the resource, or NULL if either of the REGISTRY_* constants
3453
 *   is passed in.
3454
 *
3455
 * @return
3456
 *   TRUE if the resource was found, FALSE if not.
3457
 *   NULL if either of the REGISTRY_* constants is passed in as $type.
3458
 */
3459
function _registry_check_code($type, $name = NULL) {
3460
  static $lookup_cache, $cache_update_needed;
3461

    
3462
  if ($type == 'class' && class_exists($name) || $type == 'interface' && interface_exists($name) || $type == 'trait' && trait_exists($name)) {
3463
    return TRUE;
3464
  }
3465

    
3466
  if (!isset($lookup_cache)) {
3467
    $lookup_cache = array();
3468
    if ($cache = cache_get('lookup_cache', 'cache_bootstrap')) {
3469
      $lookup_cache = $cache->data;
3470
    }
3471
  }
3472

    
3473
  // When we rebuild the registry, we need to reset this cache so
3474
  // we don't keep lookups for resources that changed during the rebuild.
3475
  if ($type == REGISTRY_RESET_LOOKUP_CACHE) {
3476
    $cache_update_needed = TRUE;
3477
    $lookup_cache = NULL;
3478
    return;
3479
  }
3480

    
3481
  // Called from drupal_page_footer, we write to permanent storage if there
3482
  // changes to the lookup cache for this request.
3483
  if ($type == REGISTRY_WRITE_LOOKUP_CACHE) {
3484
    if ($cache_update_needed) {
3485
      cache_set('lookup_cache', $lookup_cache, 'cache_bootstrap');
3486
    }
3487
    return;
3488
  }
3489

    
3490
  // $type is either 'interface' or 'class', so we only need the first letter to
3491
  // keep the cache key unique.
3492
  $cache_key = $type[0] . $name;
3493
  if (isset($lookup_cache[$cache_key])) {
3494
    if ($lookup_cache[$cache_key]) {
3495
      include_once DRUPAL_ROOT . '/' . $lookup_cache[$cache_key];
3496
    }
3497
    return (bool) $lookup_cache[$cache_key];
3498
  }
3499

    
3500
  // This function may get called when the default database is not active, but
3501
  // there is no reason we'd ever want to not use the default database for
3502
  // this query.
3503
  $file = Database::getConnection('default', 'default')
3504
    ->select('registry', 'r', array('target' => 'default'))
3505
    ->fields('r', array('filename'))
3506
    // Use LIKE here to make the query case-insensitive.
3507
    ->condition('r.name', db_like($name), 'LIKE')
3508
    ->condition('r.type', $type)
3509
    ->execute()
3510
    ->fetchField();
3511

    
3512
  // Flag that we've run a lookup query and need to update the cache.
3513
  $cache_update_needed = TRUE;
3514

    
3515
  // Misses are valuable information worth caching, so cache even if
3516
  // $file is FALSE.
3517
  $lookup_cache[$cache_key] = $file;
3518

    
3519
  if ($file) {
3520
    include_once DRUPAL_ROOT . '/' . $file;
3521
    return TRUE;
3522
  }
3523
  else {
3524
    return FALSE;
3525
  }
3526
}
3527

    
3528
/**
3529
 * Rescans all enabled modules and rebuilds the registry.
3530
 *
3531
 * Rescans all code in modules or includes directories, storing the location of
3532
 * each interface or class in the database.
3533
 */
3534
function registry_rebuild() {
3535
  system_rebuild_module_data();
3536
  registry_update();
3537
}
3538

    
3539
/**
3540
 * Updates the registry based on the latest files listed in the database.
3541
 *
3542
 * This function should be used when system_rebuild_module_data() does not need
3543
 * to be called, because it is already known that the list of files in the
3544
 * {system} table matches those in the file system.
3545
 *
3546
 * @return
3547
 *   TRUE if the registry was rebuilt, FALSE if another thread was rebuilding
3548
 *   in parallel and the current thread just waited for completion.
3549
 *
3550
 * @see registry_rebuild()
3551
 */
3552
function registry_update() {
3553
  // install_system_module() calls module_enable() which calls into this
3554
  // function during initial system installation, so the lock system is neither
3555
  // loaded nor does its storage exist yet.
3556
  $in_installer = drupal_installation_attempted();
3557
  if (!$in_installer && !lock_acquire(__FUNCTION__)) {
3558
    // Another request got the lock, wait for it to finish.
3559
    lock_wait(__FUNCTION__);
3560
    return FALSE;
3561
  }
3562

    
3563
  require_once DRUPAL_ROOT . '/includes/registry.inc';
3564
  _registry_update();
3565

    
3566
  if (!$in_installer) {
3567
    lock_release(__FUNCTION__);
3568
  }
3569
  return TRUE;
3570
}
3571

    
3572
/**
3573
 * @} End of "addtogroup registry".
3574
 */
3575

    
3576
/**
3577
 * Provides central static variable storage.
3578
 *
3579
 * All functions requiring a static variable to persist or cache data within
3580
 * a single page request are encouraged to use this function unless it is
3581
 * absolutely certain that the static variable will not need to be reset during
3582
 * the page request. By centralizing static variable storage through this
3583
 * function, other functions can rely on a consistent API for resetting any
3584
 * other function's static variables.
3585
 *
3586
 * Example:
3587
 * @code
3588
 * function language_list($field = 'language') {
3589
 *   $languages = &drupal_static(__FUNCTION__);
3590
 *   if (!isset($languages)) {
3591
 *     // If this function is being called for the first time after a reset,
3592
 *     // query the database and execute any other code needed to retrieve
3593
 *     // information about the supported languages.
3594
 *     ...
3595
 *   }
3596
 *   if (!isset($languages[$field])) {
3597
 *     // If this function is being called for the first time for a particular
3598
 *     // index field, then execute code needed to index the information already
3599
 *     // available in $languages by the desired field.
3600
 *     ...
3601
 *   }
3602
 *   // Subsequent invocations of this function for a particular index field
3603
 *   // skip the above two code blocks and quickly return the already indexed
3604
 *   // information.
3605
 *   return $languages[$field];
3606
 * }
3607
 * function locale_translate_overview_screen() {
3608
 *   // When building the content for the translations overview page, make
3609
 *   // sure to get completely fresh information about the supported languages.
3610
 *   drupal_static_reset('language_list');
3611
 *   ...
3612
 * }
3613
 * @endcode
3614
 *
3615
 * In a few cases, a function can have certainty that there is no legitimate
3616
 * use-case for resetting that function's static variable. This is rare,
3617
 * because when writing a function, it's hard to forecast all the situations in
3618
 * which it will be used. A guideline is that if a function's static variable
3619
 * does not depend on any information outside of the function that might change
3620
 * during a single page request, then it's ok to use the "static" keyword
3621
 * instead of the drupal_static() function.
3622
 *
3623
 * Example:
3624
 * @code
3625
 * function actions_do(...) {
3626
 *   // $stack tracks the number of recursive calls.
3627
 *   static $stack;
3628
 *   $stack++;
3629
 *   if ($stack > variable_get('actions_max_stack', 35)) {
3630
 *     ...
3631
 *     return;
3632
 *   }
3633
 *   ...
3634
 *   $stack--;
3635
 * }
3636
 * @endcode
3637
 *
3638
 * In a few cases, a function needs a resettable static variable, but the
3639
 * function is called many times (100+) during a single page request, so
3640
 * every microsecond of execution time that can be removed from the function
3641
 * counts. These functions can use a more cumbersome, but faster variant of
3642
 * calling drupal_static(). It works by storing the reference returned by
3643
 * drupal_static() in the calling function's own static variable, thereby
3644
 * removing the need to call drupal_static() for each iteration of the function.
3645
 * Conceptually, it replaces:
3646
 * @code
3647
 * $foo = &drupal_static(__FUNCTION__);
3648
 * @endcode
3649
 * with:
3650
 * @code
3651
 * // Unfortunately, this does not work.
3652
 * static $foo = &drupal_static(__FUNCTION__);
3653
 * @endcode
3654
 * However, the above line of code does not work, because PHP only allows static
3655
 * variables to be initializied by literal values, and does not allow static
3656
 * variables to be assigned to references.
3657
 * - http://php.net/manual/language.variables.scope.php#language.variables.scope.static
3658
 * - http://php.net/manual/language.variables.scope.php#language.variables.scope.references
3659
 * The example below shows the syntax needed to work around both limitations.
3660
 * For benchmarks and more information, see http://drupal.org/node/619666.
3661
 *
3662
 * Example:
3663
 * @code
3664
 * function user_access($string, $account = NULL) {
3665
 *   // Use the advanced drupal_static() pattern, since this is called very often.
3666
 *   static $drupal_static_fast;
3667
 *   if (!isset($drupal_static_fast)) {
3668
 *     $drupal_static_fast['perm'] = &drupal_static(__FUNCTION__);
3669
 *   }
3670
 *   $perm = &$drupal_static_fast['perm'];
3671
 *   ...
3672
 * }
3673
 * @endcode
3674
 *
3675
 * @param $name
3676
 *   Globally unique name for the variable. For a function with only one static,
3677
 *   variable, the function name (e.g. via the PHP magic __FUNCTION__ constant)
3678
 *   is recommended. For a function with multiple static variables add a
3679
 *   distinguishing suffix to the function name for each one.
3680
 * @param $default_value
3681
 *   Optional default value.
3682
 * @param $reset
3683
 *   TRUE to reset one or all variables(s). This parameter is only used
3684
 *   internally and should not be passed in; use drupal_static_reset() instead.
3685
 *   (This function's return value should not be used when TRUE is passed in.)
3686
 *
3687
 * @return
3688
 *   Returns a variable by reference.
3689
 *
3690
 * @see drupal_static_reset()
3691
 */
3692
function &drupal_static($name, $default_value = NULL, $reset = FALSE) {
3693
  static $data = array(), $default = array();
3694
  // First check if dealing with a previously defined static variable.
3695
  if (isset($data[$name]) || array_key_exists($name, $data)) {
3696
    // Non-NULL $name and both $data[$name] and $default[$name] statics exist.
3697
    if ($reset) {
3698
      // Reset pre-existing static variable to its default value.
3699
      $data[$name] = $default[$name];
3700
    }
3701
    return $data[$name];
3702
  }
3703
  // Neither $data[$name] nor $default[$name] static variables exist.
3704
  if (isset($name)) {
3705
    if ($reset) {
3706
      // Reset was called before a default is set and yet a variable must be
3707
      // returned.
3708
      return $data;
3709
    }
3710
    // First call with new non-NULL $name. Initialize a new static variable.
3711
    $default[$name] = $data[$name] = $default_value;
3712
    return $data[$name];
3713
  }
3714
  // Reset all: ($name == NULL). This needs to be done one at a time so that
3715
  // references returned by earlier invocations of drupal_static() also get
3716
  // reset.
3717
  foreach ($default as $name => $value) {
3718
    $data[$name] = $value;
3719
  }
3720
  // As the function returns a reference, the return should always be a
3721
  // variable.
3722
  return $data;
3723
}
3724

    
3725
/**
3726
 * Resets one or all centrally stored static variable(s).
3727
 *
3728
 * @param $name
3729
 *   Name of the static variable to reset. Omit to reset all variables.
3730
 *   Resetting all variables should only be used, for example, for running unit
3731
 *   tests with a clean environment.
3732
 */
3733
function drupal_static_reset($name = NULL) {
3734
  drupal_static($name, NULL, TRUE);
3735
}
3736

    
3737
/**
3738
 * Detects whether the current script is running in a command-line environment.
3739
 */
3740
function drupal_is_cli() {
3741
  return (!isset($_SERVER['SERVER_SOFTWARE']) && (php_sapi_name() == 'cli' || (is_numeric($_SERVER['argc']) && $_SERVER['argc'] > 0)));
3742
}
3743

    
3744
/**
3745
 * Formats text for emphasized display in a placeholder inside a sentence.
3746
 *
3747
 * Used automatically by format_string().
3748
 *
3749
 * @param $text
3750
 *   The text to format (plain-text).
3751
 *
3752
 * @return
3753
 *   The formatted text (html).
3754
 */
3755
function drupal_placeholder($text) {
3756
  return '<em class="placeholder">' . check_plain($text) . '</em>';
3757
}
3758

    
3759
/**
3760
 * Registers a function for execution on shutdown.
3761
 *
3762
 * Wrapper for register_shutdown_function() that catches thrown exceptions to
3763
 * avoid "Exception thrown without a stack frame in Unknown".
3764
 *
3765
 * @param $callback
3766
 *   The shutdown function to register.
3767
 * @param ...
3768
 *   Additional arguments to pass to the shutdown function.
3769
 *
3770
 * @return
3771
 *   Array of shutdown functions to be executed.
3772
 *
3773
 * @see register_shutdown_function()
3774
 * @ingroup php_wrappers
3775
 */
3776
function &drupal_register_shutdown_function($callback = NULL) {
3777
  // We cannot use drupal_static() here because the static cache is reset during
3778
  // batch processing, which breaks batch handling.
3779
  static $callbacks = array();
3780

    
3781
  if (isset($callback)) {
3782
    // Only register the internal shutdown function once.
3783
    if (empty($callbacks)) {
3784
      register_shutdown_function('_drupal_shutdown_function');
3785
    }
3786
    $args = func_get_args();
3787
    array_shift($args);
3788
    // Save callback and arguments
3789
    $callbacks[] = array('callback' => $callback, 'arguments' => $args);
3790
  }
3791
  return $callbacks;
3792
}
3793

    
3794
/**
3795
 * Executes registered shutdown functions.
3796
 */
3797
function _drupal_shutdown_function() {
3798
  $callbacks = &drupal_register_shutdown_function();
3799

    
3800
  // Set the CWD to DRUPAL_ROOT as it is not guaranteed to be the same as it
3801
  // was in the normal context of execution.
3802
  chdir(DRUPAL_ROOT);
3803

    
3804
  try {
3805
    // Manually iterate over the array instead of using a foreach loop.
3806
    // A foreach operates on a copy of the array, so any shutdown functions that
3807
    // were added from other shutdown functions would never be called.
3808
    while ($callback = current($callbacks)) {
3809
      call_user_func_array($callback['callback'], $callback['arguments']);
3810
      next($callbacks);
3811
    }
3812
  }
3813
  catch (Exception $exception) {
3814
    // If we are displaying errors, then do so with no possibility of a further uncaught exception being thrown.
3815
   require_once DRUPAL_ROOT . '/includes/errors.inc';
3816
   if (error_displayable()) {
3817
      print '<h1>Uncaught exception thrown in shutdown function.</h1>';
3818
      print '<p>' . _drupal_render_exception_safe($exception) . '</p><hr />';
3819
    }
3820
  }
3821
}
3822

    
3823
/**
3824
 * Compares the memory required for an operation to the available memory.
3825
 *
3826
 * @param $required
3827
 *   The memory required for the operation, expressed as a number of bytes with
3828
 *   optional SI or IEC binary unit prefix (e.g. 2, 3K, 5MB, 10G, 6GiB, 8bytes,
3829
 *   9mbytes).
3830
 * @param $memory_limit
3831
 *   (optional) The memory limit for the operation, expressed as a number of
3832
 *   bytes with optional SI or IEC binary unit prefix (e.g. 2, 3K, 5MB, 10G,
3833
 *   6GiB, 8bytes, 9mbytes). If no value is passed, the current PHP
3834
 *   memory_limit will be used. Defaults to NULL.
3835
 *
3836
 * @return
3837
 *   TRUE if there is sufficient memory to allow the operation, or FALSE
3838
 *   otherwise.
3839
 */
3840
function drupal_check_memory_limit($required, $memory_limit = NULL) {
3841
  if (!isset($memory_limit)) {
3842
    $memory_limit = ini_get('memory_limit');
3843
  }
3844

    
3845
  // There is sufficient memory if:
3846
  // - No memory limit is set.
3847
  // - The memory limit is set to unlimited (-1).
3848
  // - The memory limit is greater than the memory required for the operation.
3849
  return ((!$memory_limit) || ($memory_limit == -1) || (parse_size($memory_limit) >= parse_size($required)));
3850
}
3851

    
3852
/**
3853
 * Invalidates a PHP file from any active opcode caches.
3854
 *
3855
 * If the opcode cache does not support the invalidation of individual files,
3856
 * the entire cache will be flushed.
3857
 *
3858
 * @param string $filepath
3859
 *   The absolute path of the PHP file to invalidate.
3860
 */
3861
function drupal_clear_opcode_cache($filepath) {
3862
  if (!defined('PHP_VERSION_ID') || PHP_VERSION_ID < 50300) {
3863
    // Below PHP 5.3, clearstatcache does not accept any function parameters.
3864
    clearstatcache();
3865
  }
3866
  else {
3867
    clearstatcache(TRUE, $filepath);
3868
  }
3869

    
3870
  // Zend OPcache.
3871
  if (function_exists('opcache_invalidate')) {
3872
    opcache_invalidate($filepath, TRUE);
3873
  }
3874
  // APC.
3875
  if (function_exists('apc_delete_file')) {
3876
    // apc_delete_file() throws a PHP warning in case the specified file was
3877
    // not compiled yet.
3878
    // @see http://php.net/apc-delete-file
3879
    @apc_delete_file($filepath);
3880
  }
3881
}