common.inc 274 KB
Newer Older
Dries's avatar
   
Dries committed
1
2
<?php

Dries's avatar
   
Dries committed
3
4
5
6
7
8
9
10
/**
 * @file
 * Common functions that many Drupal modules will need to reference.
 *
 * The functions that are critical and need to be available even when serving
 * a cached page are instead located in bootstrap.inc.
 */

11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
/**
 * @defgroup php_wrappers PHP wrapper functions
 * @{
 * Functions that are wrappers or custom implementations of PHP functions.
 *
 * Certain PHP functions should not be used in Drupal. Instead, Drupal's
 * replacement functions should be used.
 *
 * For example, for improved or more secure UTF8-handling, or RFC-compliant
 * handling of URLs in Drupal.
 *
 * For ease of use and memorizing, all these wrapper functions use the same name
 * as the original PHP function, but prefixed with "drupal_". Beware, however,
 * that not all wrapper functions support the same arguments as the original
 * functions.
 *
 * You should always use these wrapper functions in your code.
 *
 * Wrong:
 * @code
 *   $my_substring = substr($original_string, 0, 5);
 * @endcode
 *
 * Correct:
 * @code
 *   $my_substring = drupal_substr($original_string, 0, 5);
 * @endcode
 *
39
 * @}
40
41
 */

42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
/**
 * Return status for saving which involved creating a new item.
 */
define('SAVED_NEW', 1);

/**
 * Return status for saving which involved an update to an existing item.
 */
define('SAVED_UPDATED', 2);

/**
 * Return status for saving which deleted an existing item.
 */
define('SAVED_DELETED', 3);

57
/**
58
 * The default group for system CSS files added to the page.
59
60
61
62
 */
define('CSS_SYSTEM', -100);

/**
63
 * The default group for module CSS files added to the page.
64
65
66
67
 */
define('CSS_DEFAULT', 0);

/**
68
 * The default group for theme CSS files added to the page.
69
70
71
 */
define('CSS_THEME', 100);

72
/**
73
 * The default group for JavaScript libraries or jQuery plugins added
74
 * to the page.
75
76
77
78
 */
define('JS_LIBRARY', -100);

/**
79
 * The default group for module JavaScript code added to the page.
80
81
82
83
 */
define('JS_DEFAULT', 0);

/**
84
 * The default group for theme JavaScript code added to the page.
85
86
87
 */
define('JS_THEME', 100);

88
89
90
91
92
/**
 * The default group for JavaScript settings added to the page.
 */
define('JS_SETTING', 200);

93
94
95
96
/**
 * Error code indicating that the request made by drupal_http_request() exceeded
 * the specified timeout.
 */
97
define('HTTP_REQUEST_TIMEOUT', -1);
98

99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
/**
 * Constants defining cache granularity for blocks and renderable arrays.
 *
 * Modules specify the caching patterns for their blocks using binary
 * combinations of these constants in their hook_block_info():
 *   $block[delta]['cache'] = DRUPAL_CACHE_PER_ROLE | DRUPAL_CACHE_PER_PAGE;
 * DRUPAL_CACHE_PER_ROLE is used as a default when no caching pattern is
 * specified. Use DRUPAL_CACHE_CUSTOM to disable standard block cache and
 * implement
 *
 * The block cache is cleared in cache_clear_all(), and uses the same clearing
 * policy than page cache (node, comment, user, taxonomy added or updated...).
 * Blocks requiring more fine-grained clearing might consider disabling the
 * built-in block cache (DRUPAL_NO_CACHE) and roll their own.
 *
 * Note that user 1 is excluded from block caching.
 */

/**
 * The block should not get cached. This setting should be used:
 * - for simple blocks (notably those that do not perform any db query),
 * where querying the db cache would be more expensive than directly generating
 * the content.
 * - for blocks that change too frequently.
 */
define('DRUPAL_NO_CACHE', -1);

/**
 * The block is handling its own caching in its hook_block_view(). From the
 * perspective of the block cache system, this is equivalent to DRUPAL_NO_CACHE.
 * Useful when time based expiration is needed or a site uses a node access
 * which invalidates standard block cache.
 */
define('DRUPAL_CACHE_CUSTOM', -2);

/**
 * The block or element can change depending on the roles the user viewing the
 * page belongs to. This is the default setting for blocks, used when the block
 * does not specify anything.
 */
define('DRUPAL_CACHE_PER_ROLE', 0x0001);

/**
 * The block or element can change depending on the user viewing the page.
 * This setting can be resource-consuming for sites with large number of users,
 * and thus should only be used when DRUPAL_CACHE_PER_ROLE is not sufficient.
 */
define('DRUPAL_CACHE_PER_USER', 0x0002);

/**
 * The block or element can change depending on the page being viewed.
 */
define('DRUPAL_CACHE_PER_PAGE', 0x0004);

/**
 * The block or element is the same for every user on every page where it is visible.
 */
define('DRUPAL_CACHE_GLOBAL', 0x0008);

158
/**
159
 * Add content to a specified region.
160
161
 *
 * @param $region
162
 *   Page region the content is added to.
163
 * @param $data
164
 *   Content to be added.
165
 */
166
function drupal_add_region_content($region = NULL, $data = NULL) {
167
168
  static $content = array();

169
  if (isset($region) && isset($data)) {
170
171
172
173
174
175
    $content[$region][] = $data;
  }
  return $content;
}

/**
176
 * Get assigned content for a given region.
177
178
 *
 * @param $region
179
180
 *   A specified region to fetch content for. If NULL, all regions will be
 *   returned.
181
 * @param $delimiter
182
 *   Content to be inserted between imploded array elements.
183
 */
184
185
function drupal_get_region_content($region = NULL, $delimiter = ' ') {
  $content = drupal_add_region_content();
186
187
  if (isset($region)) {
    if (isset($content[$region]) && is_array($content[$region])) {
Steven Wittens's avatar
Steven Wittens committed
188
      return implode($delimiter, $content[$region]);
189
    }
190
191
192
193
  }
  else {
    foreach (array_keys($content) as $region) {
      if (is_array($content[$region])) {
Steven Wittens's avatar
Steven Wittens committed
194
        $content[$region] = implode($delimiter, $content[$region]);
195
196
197
198
199
200
      }
    }
    return $content;
  }
}

201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
/**
 * Get the name of the currently active install profile.
 *
 * When this function is called during Drupal's initial installation process,
 * the name of the profile that's about to be installed is stored in the global
 * installation state. At all other times, the standard Drupal systems variable
 * table contains the name of the current profile, and we can call variable_get()
 * to determine what one is active.
 *
 * @return $profile
 *   The name of the install profile.
 */
function drupal_get_profile() {
  global $install_state;

  if (isset($install_state['parameters']['profile'])) {
    $profile = $install_state['parameters']['profile'];
  }
  else {
220
    $profile = variable_get('install_profile', 'standard');
221
222
223
224
225
226
  }

  return $profile;
}


Dries's avatar
   
Dries committed
227
/**
Dries's avatar
   
Dries committed
228
 * Set the breadcrumb trail for the current page.
Dries's avatar
   
Dries committed
229
 *
Dries's avatar
   
Dries committed
230
231
232
 * @param $breadcrumb
 *   Array of links, starting with "home" and proceeding up to but not including
 *   the current page.
Kjartan's avatar
Kjartan committed
233
 */
Dries's avatar
   
Dries committed
234
function drupal_set_breadcrumb($breadcrumb = NULL) {
235
  $stored_breadcrumb = &drupal_static(__FUNCTION__);
Dries's avatar
   
Dries committed
236

237
  if (isset($breadcrumb)) {
Dries's avatar
   
Dries committed
238
239
240
241
242
    $stored_breadcrumb = $breadcrumb;
  }
  return $stored_breadcrumb;
}

Dries's avatar
   
Dries committed
243
244
245
/**
 * Get the breadcrumb trail for the current page.
 */
Dries's avatar
   
Dries committed
246
247
248
function drupal_get_breadcrumb() {
  $breadcrumb = drupal_set_breadcrumb();

249
  if (!isset($breadcrumb)) {
Dries's avatar
   
Dries committed
250
251
252
253
254
255
    $breadcrumb = menu_get_active_breadcrumb();
  }

  return $breadcrumb;
}

Dries's avatar
Dries committed
256
/**
Dries's avatar
   
Dries committed
257
 * Add output to the head tag of the HTML page.
258
 *
259
 * This function can be called as long as the headers aren't sent. Pass no
260
261
262
263
264
265
266
267
268
269
270
271
272
 * arguments (or NULL for both) to retrieve the currently stored elements.
 *
 * @param $data
 *   A renderable array. If the '#type' key is not set then 'html_tag' will be
 *   added as the default '#type'.
 * @param $key
 *   A unique string key to allow implementations of hook_html_head_alter() to
 *   identify the element in $data. Required if $data is not NULL.
 *
 * @return
 *   An array of all stored HEAD elements.
 *
 * @see theme_html_tag()
Dries's avatar
Dries committed
273
 */
274
275
function drupal_add_html_head($data = NULL, $key = NULL) {
  $stored_head = &drupal_static(__FUNCTION__);
Dries's avatar
Dries committed
276

277
278
279
280
281
282
283
284
285
286
  if (!isset($stored_head)) {
    // Make sure the defaults, including Content-Type, come first.
    $stored_head = _drupal_default_html_head();
  }

  if (isset($data) && isset($key)) {
    if (!isset($data['#type'])) {
      $data['#type'] = 'html_tag';
    }
    $stored_head[$key] = $data;
Dries's avatar
Dries committed
287
288
289
290
  }
  return $stored_head;
}

Dries's avatar
   
Dries committed
291
/**
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
 * Returns elements that are always displayed in the HEAD tag of the HTML page.
 */
function _drupal_default_html_head() {
  // Add default elements. Make sure the Content-Type comes first because the
  // IE browser may be vulnerable to XSS via encoding attacks from any content
  // that comes before this META tag, such as a TITLE tag.
  $elements['system_meta_content_type'] = array(
    '#type' => 'html_tag',
    '#tag' => 'meta',
    '#attributes' => array(
      'http-equiv' => 'Content-Type',
      'content' => 'text/html; charset=utf-8',
    ),
    // Security: This always has to be output first.
    '#weight' => -1000,
  );
  // Show Drupal and the major version number in the META GENERATOR tag.
  // Get the major version.
  list($version, ) = explode('.', VERSION);
  $elements['system_meta_generator'] = array(
    '#type' => 'html_tag',
    '#tag' => 'meta',
    '#attributes' => array(
      'name' => 'Generator',
      'content' => 'Drupal ' . $version . ' (http://drupal.org)',
    ),
  );
  // Also send the generator in the HTTP header.
  $elements['system_meta_generator']['#attached']['drupal_add_http_header'][] = array('X-Generator', $elements['system_meta_generator']['#attributes']['content']);
  return $elements;
}

/**
 * Retrieve output to be displayed in the HEAD tag of the HTML page.
Dries's avatar
   
Dries committed
326
 */
Dries's avatar
Dries committed
327
function drupal_get_html_head() {
328
329
330
  $elements = drupal_add_html_head();
  drupal_alter('html_head', $elements);
  return drupal_render($elements);
Dries's avatar
Dries committed
331
332
}

333
/**
334
335
 * Add a feed URL for the current page.
 *
336
337
 * This function can be called as long the HTML header hasn't been sent.
 *
338
 * @param $url
339
 *   An internal system path or a fully qualified external URL of the feed.
340
 * @param $title
341
 *   The title of the feed.
342
 */
343
function drupal_add_feed($url = NULL, $title = '') {
344
  $stored_feed_links = &drupal_static(__FUNCTION__, array());
345

346
  if (isset($url)) {
347
    $stored_feed_links[$url] = theme('feed_icon', array('url' => $url, 'title' => $title));
348

349
350
351
352
353
354
355
356
    drupal_add_html_head_link(array(
      'rel' => 'alternate',
      'type' => 'application/rss+xml',
      'title' => $title,
      // Force the URL to be absolute, for consistency with other <link> tags
      // output by Drupal.
      'href' => url($url, array('absolute' => TRUE)),
    ));
357
358
359
360
361
362
363
364
  }
  return $stored_feed_links;
}

/**
 * Get the feed URLs for the current page.
 *
 * @param $delimiter
365
 *   A delimiter to split feeds by.
366
367
368
369
370
371
 */
function drupal_get_feeds($delimiter = "\n") {
  $feeds = drupal_add_feed();
  return implode($feeds, $delimiter);
}

Dries's avatar
   
Dries committed
372
/**
373
 * @defgroup http_handling HTTP handling
Dries's avatar
   
Dries committed
374
 * @{
Dries's avatar
   
Dries committed
375
 * Functions to properly handle HTTP responses.
Dries's avatar
   
Dries committed
376
377
 */

378
/**
379
 * Process a URL query parameter array to remove unwanted elements.
380
381
 *
 * @param $query
382
 *   (optional) An array to be processed. Defaults to $_GET.
383
 * @param $exclude
384
385
 *   (optional) A list of $query array keys to remove. Use "parent[child]" to
 *   exclude nested items. Defaults to array('q').
386
 * @param $parent
387
388
 *   Internal use only. Used to build the $query array key for nested items.
 *
389
 * @return
390
 *   An array containing query parameters, which can be used for url().
391
 */
392
393
394
395
396
397
398
399
400
401
402
403
function drupal_get_query_parameters(array $query = NULL, array $exclude = array('q'), $parent = '') {
  // Set defaults, if none given.
  if (!isset($query)) {
    $query = $_GET;
  }
  // If $exclude is empty, there is nothing to filter.
  if (empty($exclude)) {
    return $query;
  }
  elseif (!$parent) {
    $exclude = array_flip($exclude);
  }
404

405
  $params = array();
406
  foreach ($query as $key => $value) {
407
408
409
    $string_key = ($parent ? $parent . '[' . $key . ']' : $key);
    if (isset($exclude[$string_key])) {
      continue;
410
411
    }

412
413
414
415
416
    if (is_array($value)) {
      $params[$key] = drupal_get_query_parameters($value, $exclude, $string_key);
    }
    else {
      $params[$key] = $value;
417
    }
418
419
420
421
422
  }

  return $params;
}

423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
/**
 * Split an URL-encoded query string into an array.
 *
 * @param $query
 *   The query string to split.
 *
 * @return
 *   An array of url decoded couples $param_name => $value.
 */
function drupal_get_query_array($query) {
  $result = array();
  if (!empty($query)) {
    foreach (explode('&', $query) as $param) {
      $param = explode('=', $param);
      $result[$param[0]] = isset($param[1]) ? rawurldecode($param[1]) : '';
    }
  }
  return $result;
}

443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
/**
 * Parse an array into a valid, rawurlencoded query string.
 *
 * This differs from http_build_query() as we need to rawurlencode() (instead of
 * urlencode()) all query parameters.
 *
 * @param $query
 *   The query parameter array to be processed, e.g. $_GET.
 * @param $parent
 *   Internal use only. Used to build the $query array key for nested items.
 *
 * @return
 *   A rawurlencoded string which can be used as or appended to the URL query
 *   string.
 *
 * @see drupal_get_query_parameters()
 * @ingroup php_wrappers
 */
function drupal_http_build_query(array $query, $parent = '') {
  $params = array();

  foreach ($query as $key => $value) {
    $key = ($parent ? $parent . '[' . rawurlencode($key) . ']' : rawurlencode($key));
466

467
    // Recurse into children.
468
    if (is_array($value)) {
469
470
471
472
473
      $params[] = drupal_http_build_query($value, $key);
    }
    // If a query parameter value is NULL, only append its key.
    elseif (!isset($value)) {
      $params[] = $key;
474
475
    }
    else {
476
477
      // For better readability of paths in query strings, we decode slashes.
      $params[] = $key . '=' . str_replace('%2F', '/', rawurlencode($value));
478
479
480
481
482
483
    }
  }

  return implode('&', $params);
}

484
/**
485
 * Prepare a 'destination' URL query parameter for use in combination with drupal_goto().
486
 *
487
488
489
490
 * Used to direct the user back to the referring page after completing a form.
 * By default the current URL is returned. If a destination exists in the
 * previous request, that destination is returned. As such, a destination can
 * persist across multiple pages.
491
492
493
494
 *
 * @see drupal_goto()
 */
function drupal_get_destination() {
495
496
497
498
499
500
  $destination = &drupal_static(__FUNCTION__);

  if (isset($destination)) {
    return $destination;
  }

501
  if (isset($_GET['destination'])) {
502
    $destination = array('destination' => $_GET['destination']);
503
504
  }
  else {
505
506
    $path = $_GET['q'];
    $query = drupal_http_build_query(drupal_get_query_parameters());
507
    if ($query != '') {
508
      $path .= '?' . $query;
509
    }
510
511
512
513
514
515
    $destination = array('destination' => $path);
  }
  return $destination;
}

/**
516
517
518
519
520
 * Wrapper around parse_url() to parse a system URL string into an associative array, suitable for url().
 *
 * This function should only be used for URLs that have been generated by the
 * system, resp. url(). It should not be used for URLs that come from external
 * sources, or URLs that link to external resources.
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
 *
 * The returned array contains a 'path' that may be passed separately to url().
 * For example:
 * @code
 *   $options = drupal_parse_url($_GET['destination']);
 *   $my_url = url($options['path'], $options);
 *   $my_link = l('Example link', $options['path'], $options);
 * @endcode
 *
 * This is required, because url() does not support relative URLs containing a
 * query string or fragment in its $path argument. Instead, any query string
 * needs to be parsed into an associative query parameter array in
 * $options['query'] and the fragment into $options['fragment'].
 *
 * @param $url
 *   The URL string to parse, f.e. $_GET['destination'].
 *
 * @return
 *   An associative array containing the keys:
 *   - 'path': The path of the URL. If the given $url is external, this includes
 *     the scheme and host.
 *   - 'query': An array of query parameters of $url, if existent.
 *   - 'fragment': The fragment of $url, if existent.
 *
 * @see url()
 * @see drupal_goto()
 * @ingroup php_wrappers
 */
function drupal_parse_url($url) {
  $options = array(
    'path' => NULL,
    'query' => array(),
    'fragment' => '',
  );

  // External URLs: not using parse_url() here, so we do not have to rebuild
  // the scheme, host, and path without having any use for it.
  if (strpos($url, '://') !== FALSE) {
    // Split off everything before the query string into 'path'.
    $parts = explode('?', $url);
    $options['path'] = $parts[0];
    // If there is a query string, transform it into keyed query parameters.
    if (isset($parts[1])) {
      $query_parts = explode('#', $parts[1]);
      parse_str($query_parts[0], $options['query']);
      // Take over the fragment, if there is any.
      if (isset($query_parts[1])) {
        $options['fragment'] = $query_parts[1];
      }
    }
  }
  // Internal URLs.
  else {
574
575
576
577
578
    // parse_url() does not support relative URLs, so make it absolute. E.g. the
    // relative URL "foo/bar:1" isn't properly parsed.
    $parts = parse_url('http://example.com/' . $url);
    // Strip the leading slash that was just added.
    $options['path'] = substr($parts['path'], 1);
579
580
581
582
583
584
585
    if (isset($parts['query'])) {
      parse_str($parts['query'], $options['query']);
    }
    if (isset($parts['fragment'])) {
      $options['fragment'] = $parts['fragment'];
    }
  }
586
587
588
589
590
591
592
  // The 'q' parameter contains the path of the current page if clean URLs are
  // disabled. It overrides the 'path' of the URL when present, even if clean
  // URLs are enabled, due to how Apache rewriting rules work.
  if (isset($options['query']['q'])) {
    $options['path'] = $options['query']['q'];
    unset($options['query']['q']);
  }
593
594
595
596
597

  return $options;
}

/**
598
 * Encodes a Drupal path for use in a URL.
599
 *
600
 * For aesthetic reasons slashes are not escaped.
601
 *
602
603
 * Note that url() takes care of calling this function, so a path passed to that
 * function should not be encoded in advance.
604
605
 *
 * @param $path
606
 *   The Drupal path to encode.
607
608
 */
function drupal_encode_path($path) {
609
  return str_replace('%2F', '/', rawurlencode($path));
610
611
}

Kjartan's avatar
Kjartan committed
612
/**
Dries's avatar
   
Dries committed
613
 * Send the user to a different Drupal page.
Kjartan's avatar
Kjartan committed
614
 *
Dries's avatar
   
Dries committed
615
616
 * This issues an on-site HTTP redirect. The function makes sure the redirected
 * URL is formatted correctly.
Kjartan's avatar
Kjartan committed
617
 *
618
619
620
621
622
623
 * If a destination was specified in the current request's URI (i.e.,
 * $_GET['destination']) then it will override the $path and $options values
 * passed to this function. This provides the flexibility to build a link to
 * user/login and override the default redirection so that the user is
 * redirected to a specific path after logging in:
 * @code
624
625
 *   $query = array('destination' => "node/$node->nid");
 *   $link = l(t('Log in'), 'user/login', array('query' => $query));
626
 * @endcode
627
 *
628
629
 * Drupal will ensure that messages set by drupal_set_message() and other
 * session data are written to the database before the user is redirected.
Dries's avatar
   
Dries committed
630
 *
631
632
 * This function ends the request; use it instead of a return in your menu
 * callback.
Dries's avatar
   
Dries committed
633
634
 *
 * @param $path
635
 *   A Drupal path or a full URL.
636
637
 * @param $options
 *   An associative array of additional URL options to pass to url().
638
639
640
641
642
643
644
645
 * @param $http_response_code
 *   Valid values for an actual "goto" as per RFC 2616 section 10.3 are:
 *   - 301 Moved Permanently (the recommended value for most redirects)
 *   - 302 Found (default in Drupal and PHP, sometimes used for spamming search
 *         engines)
 *   - 303 See Other
 *   - 304 Not Modified
 *   - 305 Use Proxy
646
 *   - 307 Temporary Redirect (alternative to "503 Site Down for Maintenance")
647
 *   Note: Other values are defined by RFC 2616, but are rarely used and poorly
648
 *   supported.
649
 *
650
 * @see drupal_get_destination()
651
 * @see url()
Kjartan's avatar
Kjartan committed
652
 */
653
654
function drupal_goto($path = '', array $options = array(), $http_response_code = 302) {
  // A destination in $_GET always overrides the function arguments.
655
656
  // We do not allow absolute URLs to be passed via $_GET, as this can be an attack vector.
  if (isset($_GET['destination']) && !url_is_external($_GET['destination'])) {
657
    $destination = drupal_parse_url($_GET['destination']);
658
659
660
    $path = $destination['path'];
    $options['query'] = $destination['query'];
    $options['fragment'] = $destination['fragment'];
661
662
  }

663
664
665
666
  drupal_alter('drupal_goto', $path, $options, $http_response_code);

  // The 'Location' HTTP header must be absolute.
  $options['absolute'] = TRUE;
667

668
  $url = url($path, $options);
Kjartan's avatar
Kjartan committed
669

670
  header('Location: ' . $url, TRUE, $http_response_code);
671
672

  // The "Location" header sends a redirect status code to the HTTP daemon. In
673
674
  // some cases this can be wrong, so we make sure none of the code below the
  // drupal_goto() call gets executed upon redirection.
675
  drupal_exit($url);
Kjartan's avatar
Kjartan committed
676
677
}

678
/**
679
680
681
682
683
684
 * Deliver a "site is under maintenance" message to the browser.
 *
 * Page callback functions wanting to report a "site offline" message should
 * return MENU_SITE_OFFLINE instead of calling drupal_site_offline(). However,
 * functions that are invoked in contexts where that return value might not
 * bubble up to menu_execute_active_handler() should call drupal_site_offline().
685
686
 */
function drupal_site_offline() {
687
  drupal_deliver_page(MENU_SITE_OFFLINE);
688
689
}

Kjartan's avatar
Kjartan committed
690
/**
691
692
693
694
695
696
 * Deliver a "page not found" error to the browser.
 *
 * Page callback functions wanting to report a "page not found" message should
 * return MENU_NOT_FOUND instead of calling drupal_not_found(). However,
 * functions that are invoked in contexts where that return value might not
 * bubble up to menu_execute_active_handler() should call drupal_not_found().
Kjartan's avatar
Kjartan committed
697
 */
Dries's avatar
   
Dries committed
698
function drupal_not_found() {
699
  drupal_deliver_page(MENU_NOT_FOUND);
Dries's avatar
   
Dries committed
700
}
Dries's avatar
   
Dries committed
701

Dries's avatar
   
Dries committed
702
/**
703
704
705
706
707
708
 * Deliver a "access denied" error to the browser.
 *
 * Page callback functions wanting to report an "access denied" message should
 * return MENU_ACCESS_DENIED instead of calling drupal_access_denied(). However,
 * functions that are invoked in contexts where that return value might not
 * bubble up to menu_execute_active_handler() should call drupal_access_denied().
Dries's avatar
   
Dries committed
709
710
 */
function drupal_access_denied() {
711
  drupal_deliver_page(MENU_ACCESS_DENIED);
Dries's avatar
   
Dries committed
712
713
}

Dries's avatar
   
Dries committed
714
/**
Dries's avatar
   
Dries committed
715
 * Perform an HTTP request.
Dries's avatar
   
Dries committed
716
 *
717
718
 * This is a flexible and powerful HTTP client implementation. Correctly
 * handles GET, POST, PUT or any other HTTP requests. Handles redirects.
Dries's avatar
   
Dries committed
719
720
721
 *
 * @param $url
 *   A string containing a fully qualified URI.
722
723
724
725
726
727
728
729
730
731
732
733
 * @param array $options
 *   (optional) An array that can have one or more of the following elements:
 *   - headers: An array containing request headers to send as name/value pairs.
 *   - method: A string containing the request method. Defaults to 'GET'.
 *   - data: A string containing the request body, formatted as
 *     'param=value&param=value&...'. Defaults to NULL.
 *   - max_redirects: An integer representing how many times a redirect
 *     may be followed. Defaults to 3.
 *   - timeout: A float representing the maximum number of seconds the function
 *     call may take. The default is 30 seconds. If a timeout occurs, the error
 *     code is set to the HTTP_REQUEST_TIMEOUT constant.
 *   - context: A context resource created with stream_context_create().
734
 *
735
736
737
738
739
740
741
742
743
744
 * @return object
 *   An object that can have one or more of the following components:
 *   - request: A string containing the request body that was sent.
 *   - code: An integer containing the response status code, or the error code
 *     if an error occurred.
 *   - protocol: The response protocol (e.g. HTTP/1.1 or HTTP/1.0).
 *   - status_message: The status message from the response, if a response was
 *     received.
 *   - redirect_code: If redirected, an integer containing the initial response
 *     status code.
745
746
 *   - redirect_url: If redirected, a string containing the URL of the redirect
 *     target.
747
748
749
750
751
 *   - error: If an error occurred, the error message. Otherwise not set.
 *   - headers: An array containing the response headers as name/value pairs.
 *     HTTP header names are case-insensitive (RFC 2616, section 4.2), so for
 *     easy access the array keys are returned in lower case.
 *   - data: A string containing the response body that was received.
Dries's avatar
   
Dries committed
752
 */
753
function drupal_http_request($url, array $options = array()) {
754
  $result = new stdClass();
Dries's avatar
   
Dries committed
755

756
757
758
759
  // Parse the URL and make sure we can handle the schema.
  $uri = @parse_url($url);

  if ($uri == FALSE) {
760
    $result->error = 'unable to parse URL';
761
    $result->code = -1001;
762
763
764
    return $result;
  }

765
766
767
768
769
  if (!isset($uri['scheme'])) {
    $result->error = 'missing schema';
    $result->code = -1002;
    return $result;
  }
770

771
772
773
774
775
776
777
778
  timer_start(__FUNCTION__);

  // Merge the default options.
  $options += array(
    'headers' => array(),
    'method' => 'GET',
    'data' => NULL,
    'max_redirects' => 3,
779
780
    'timeout' => 30.0,
    'context' => NULL,
781
  );
782
783
  // stream_socket_client() requires timeout to be a float.
  $options['timeout'] = (float) $options['timeout'];
784

Dries's avatar
   
Dries committed
785
786
  switch ($uri['scheme']) {
    case 'http':
787
    case 'feed':
Dries's avatar
Dries committed
788
      $port = isset($uri['port']) ? $uri['port'] : 80;
789
790
791
792
793
      $socket = 'tcp://' . $uri['host'] . ':' . $port;
      // RFC 2616: "non-standard ports MUST, default ports MAY be included".
      // We don't add the standard port to prevent from breaking rewrite rules
      // checking the host that do not take into account the port number.
      $options['headers']['Host'] = $uri['host'] . ($port != 80 ? ':' . $port : '');
Dries's avatar
   
Dries committed
794
795
      break;
    case 'https':
796
      // Note: Only works when PHP is compiled with OpenSSL support.
Dries's avatar
Dries committed
797
      $port = isset($uri['port']) ? $uri['port'] : 443;
798
799
      $socket = 'ssl://' . $uri['host'] . ':' . $port;
      $options['headers']['Host'] = $uri['host'] . ($port != 443 ? ':' . $port : '');
Dries's avatar
   
Dries committed
800
801
      break;
    default:
802
      $result->error = 'invalid schema ' . $uri['scheme'];
803
      $result->code = -1003;
Dries's avatar
   
Dries committed
804
805
806
      return $result;
  }

807
808
809
810
811
812
813
814
  if (empty($options['context'])) {
    $fp = @stream_socket_client($socket, $errno, $errstr, $options['timeout']);
  }
  else {
    // Create a stream with context. Allows verification of a SSL certificate.
    $fp = @stream_socket_client($socket, $errno, $errstr, $options['timeout'], STREAM_CLIENT_CONNECT, $options['context']);
  }

Dries's avatar
   
Dries committed
815
  // Make sure the socket opened properly.
Dries's avatar
   
Dries committed
816
  if (!$fp) {
817
818
    // When a network error occurs, we use a negative number so it does not
    // clash with the HTTP status codes.
819
    $result->code = -$errno;
820
    $result->error = trim($errstr) ? trim($errstr) : t('Error opening socket @socket', array('@socket' => $socket));
821
822
823
824

    // Mark that this request failed. This will trigger a check of the web
    // server's ability to make outgoing HTTP requests the next time that
    // requirements checking is performed.
825
    // See system_requirements().
826
827
    variable_set('drupal_http_request_fails', TRUE);

Dries's avatar
   
Dries committed
828
829
830
    return $result;
  }

Dries's avatar
   
Dries committed
831
  // Construct the path to act on.
Dries's avatar
Dries committed
832
833
  $path = isset($uri['path']) ? $uri['path'] : '/';
  if (isset($uri['query'])) {
834
    $path .= '?' . $uri['query'];
Dries's avatar
   
Dries committed
835
836
  }

837
838
839
  // Merge the default headers.
  $options['headers'] += array(
    'User-Agent' => 'Drupal (+http://drupal.org/)',
Dries's avatar
   
Dries committed
840
841
  );

842
843
844
845
  // Only add Content-Length if we actually have any content or if it is a POST
  // or PUT request. Some non-standard servers get confused by Content-Length in
  // at least HEAD/GET requests, and Squid always requires Content-Length in
  // POST/PUT requests.
846
847
848
  $content_length = strlen($options['data']);
  if ($content_length > 0 || $options['method'] == 'POST' || $options['method'] == 'PUT') {
    $options['headers']['Content-Length'] = $content_length;
849
850
851
  }

  // If the server URL has a user then attempt to use basic authentication.
852
  if (isset($uri['user'])) {
853
    $options['headers']['Authorization'] = 'Basic ' . base64_encode($uri['user'] . (isset($uri['pass']) ? ':' . $uri['pass'] : ''));
854
855
  }

856
857
858
859
860
861
  // If the database prefix is being used by SimpleTest to run the tests in a copied
  // database then set the user-agent header to the database prefix so that any
  // calls to other Drupal pages will run the SimpleTest prefixed database. The
  // user-agent is used to ensure that multiple testing sessions running at the
  // same time won't interfere with each other as they would if the database
  // prefix were stored statically in a file or database variable.
862
863
864
  $test_info = &$GLOBALS['drupal_test_info'];
  if (!empty($test_info['test_run_id'])) {
    $options['headers']['User-Agent'] = drupal_generate_test_ua($test_info['test_run_id']);
865
866
  }

867
  $request = $options['method'] . ' ' . $path . " HTTP/1.0\r\n";
868
  foreach ($options['headers'] as $name => $value) {
869
    $request .= $name . ': ' . trim($value) . "\r\n";
Dries's avatar
   
Dries committed
870
  }
871
  $request .= "\r\n" . $options['data'];
Dries's avatar
   
Dries committed
872
  $result->request = $request;
873
874
875
876
877
878
  // Calculate how much time is left of the original timeout value.
  $timeout = $options['timeout'] - timer_read(__FUNCTION__) / 1000;
  if ($timeout > 0) {
    stream_set_timeout($fp, floor($timeout), floor(1000000 * fmod($timeout, 1)));
    fwrite($fp, $request);
  }
Dries's avatar
   
Dries committed
879

880
881
882
883
884
  // Fetch response. Due to PHP bugs like http://bugs.php.net/bug.php?id=43782
  // and http://bugs.php.net/bug.php?id=46049 we can't rely on feof(), but
  // instead must invoke stream_get_meta_data() each iteration.
  $info = stream_get_meta_data($fp);
  $alive = !$info['eof'] && !$info['timed_out'];
885
  $response = '';
886
887

  while ($alive) {
888
889
890
    // Calculate how much time is left of the original timeout value.
    $timeout = $options['timeout'] - timer_read(__FUNCTION__) / 1000;
    if ($timeout <= 0) {
891
892
      $info['timed_out'] = TRUE;
      break;
893
894
    }
    stream_set_timeout($fp, floor($timeout), floor(1000000 * fmod($timeout, 1)));
895
896
897
898
    $chunk = fread($fp, 1024);
    $response .= $chunk;
    $info = stream_get_meta_data($fp);
    $alive = !$info['eof'] && !$info['timed_out'] && $chunk;
Dries's avatar
   
Dries committed
899
900
901
  }
  fclose($fp);

902
903
904
905
906
  if ($info['timed_out']) {
    $result->code = HTTP_REQUEST_TIMEOUT;
    $result->error = 'request timed out';
    return $result;
  }
907
  // Parse response headers from the response body.
908
909
910
  // Be tolerant of malformed HTTP responses that separate header and body with
  // \n\n or \r\r instead of \r\n\r\n.
  list($response, $result->data) = preg_split("/\r\n\r\n|\n\n|\r\r/", $response, 2);
911
  $response = preg_split("/\r\n|\n|\r/", $response);
912

913
  // Parse the response status line.
914
915
916
917
  list($protocol, $code, $status_message) = explode(' ', trim(array_shift($response)), 3);
  $result->protocol = $protocol;
  $result->status_message = $status_message;

Dries's avatar
   
Dries committed
918
919
  $result->headers = array();

920
921
  // Parse the response headers.
  while ($line = trim(array_shift($response))) {
922
923
924
    list($name, $value) = explode(':', $line, 2);
    $name = strtolower($name);
    if (isset($result->headers[$name]) && $name == 'set-cookie') {
925
926
      // RFC 2109: the Set-Cookie response header comprises the token Set-
      // Cookie:, followed by a comma-separated list of one or more cookies.
927
      $result->headers[$name] .= ',' . trim($value);
928
929
    }
    else {
930
      $result->headers[$name] = trim($value);
931
    }
Dries's avatar
   
Dries committed
932
933
934
  }

  $responses = array(
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
    100 => 'Continue',
    101 => 'Switching Protocols',
    200 => 'OK',
    201 => 'Created',
    202 => 'Accepted',
    203 => 'Non-Authoritative Information',
    204 => 'No Content',
    205 => 'Reset Content',
    206 => 'Partial Content',
    300 => 'Multiple Choices',
    301 => 'Moved Permanently',
    302 => 'Found',
    303 => 'See Other',
    304 => 'Not Modified',
    305 => 'Use Proxy',
    307 => 'Temporary Redirect',
    400 => 'Bad Request',
    401 => 'Unauthorized',
    402 => 'Payment Required',
    403 => 'Forbidden',
    404 => 'Not Found',
    405 => 'Method Not Allowed',
    406 => 'Not Acceptable',
    407 => 'Proxy Authentication Required',
    408 => 'Request Time-out',
    409 => 'Conflict',
    410 => 'Gone',
    411 => 'Length Required',
    412 => 'Precondition Failed',
    413 => 'Request Entity Too Large',
    414 => 'Request-URI Too Large',
    415 => 'Unsupported Media Type',
    416 => 'Requested range not satisfiable',
    417 => 'Expectation Failed',
    500 => 'Internal Server Error',
    501 => 'Not Implemented',
    502 => 'Bad Gateway',
    503 => 'Service Unavailable',
    504 => 'Gateway Time-out',
    505 => 'HTTP Version not supported',
Dries's avatar
   
Dries committed
975
  );
976
977
  // RFC 2616 states that all unknown HTTP codes must be treated the same as the
  // base code in their class.
Dries's avatar
   
Dries committed
978
979
980
  if (!isset($responses[$code])) {
    $code = floor($code / 100) * 100;
  }
981
  $result->code = $code;
Dries's avatar
   
Dries committed
982
983
984
985
986
987
988
989

  switch ($code) {
    case 200: // OK
    case 304: // Not modified
      break;
    case 301: // Moved permanently
    case 302: // Moved temporarily
    case 307: // Moved temporarily
990
      $location = $result->headers['location'];
991
992
993
994
995
996
      $options['timeout'] -= timer_read(__FUNCTION__) / 1000;
      if ($options['timeout'] <= 0) {
        $result->code = HTTP_REQUEST_TIMEOUT;
        $result->error = 'request timed out';
      }
      elseif ($options['max_redirects']) {
997
998
999
        // Redirect to the new location.
        $options['max_redirects']--;
        $result = drupal_http_request($location, $options);
1000
        $result->redirect_code = $code;
Dries's avatar
   
Dries committed
1001
      }
1002
1003
1004
      if (!isset($result->redirect_url)) {
        $result->redirect_url = $location;
      }
Dries's avatar
   
Dries committed
1005
1006
      break;
    default:
1007
      $result->error = $status_message;
Dries's avatar
   
Dries committed
1008
1009
1010
1011
  }

  return $result;
}
Dries's avatar
   
Dries committed
1012
1013
1014
/**
 * @} End of "HTTP handling".
 */
Dries's avatar
   
Dries committed
1015

Dries's avatar
   
Dries committed
1016
function _fix_gpc_magic(&$item) {
Dries's avatar
Dries committed
1017
  if (is_array($item)) {
Kjartan's avatar
Kjartan committed
1018
1019
1020
    array_walk($item, '_fix_gpc_magic');
  }
  else {
Kjartan's avatar
Kjartan committed
1021
    $item = stripslashes($item);
Dries's avatar
   
Dries committed
1022
1023
1024
  }
}

1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
/**
 * Helper function to strip slashes from $_FILES skipping over the tmp_name keys
 * since PHP generates single backslashes for file paths on Windows systems.
 *
 * tmp_name does not have backslashes added see
 * http://php.net/manual/en/features.file-upload.php#42280
 */
function _fix_gpc_magic_files(&$item, $key) {
  if ($key != 'tmp_name') {
    if (is_array($item)) {
      array_walk($item, '_fix_gpc_magic_files');
    }
    else {
      $item = stripslashes($item);
    }
  }
}

Dries's avatar
   
Dries committed
1043
/**
1044
 * Fix double-escaping problems caused by "magic quotes" in some PHP installations.
Dries's avatar
   
Dries committed
1045
 */
Dries's avatar
   
Dries committed
1046
function fix_gpc_magic() {
1047
  static $fixed = FALSE;
Dries's avatar
   
Dries committed
1048
  if (!$fixed && ini_get('magic_quotes_gpc')) {
Dries's avatar
Dries committed
1049
1050
1051
1052
    array_walk($_GET, '_fix_gpc_magic');
    array_walk($_POST, '_fix_gpc_magic');
    array_walk($_COOKIE, '_fix_gpc_magic');
    array_walk($_REQUEST, '_fix_gpc_magic');
1053
    array_walk($_FILES, '_fix_gpc_magic_files');
Dries's avatar
Dries committed
1054
  }
1055
  $fixed = TRUE;
Dries's avatar
   
Dries committed
1056
1057
}

Kjartan's avatar
Kjartan committed
1058
/**
Dries's avatar
   
Dries committed
1059
 * @defgroup validation Input validation
Dries's avatar
   
Dries committed
1060
 * @{
Dries's avatar
   
Dries committed
1061
 * Functions to validate user input.
Kjartan's avatar
Kjartan committed
1062
1063
 */

1064
/**
Dries's avatar
   
Dries committed
1065
1066
1067
 * Verify the syntax of the given e-mail address.
 *
 * Empty e-mail addresses are allowed. See RFC 2822 for details.
1068
 *
Dries's avatar
   
Dries committed
1069
 * @param $mail
1070
 *   A string containing an e-mail address.
Dries's avatar
   
Dries committed
1071
 * @return
Dries's avatar
   
Dries committed
1072
 *   TRUE if the address is in a valid format.
1073
 */
Dries's avatar
   
Dries committed
1074
function valid_email_address($mail) {
1075
  return (bool)filter_var($mail, FILTER_VALIDATE_EMAIL);
1076
1077
}

Dries's avatar
   
Dries committed
1078
1079
1080
/**
 * Verify the syntax of the given URL.
 *
1081
1082
 * This function should only be used on actual URLs. It should not be used for
 * Drupal menu paths, which can contain arbitrary characters.
1083
 * Valid values per RFC 3986.
Dries's avatar
   
Dries committed
1084
 * @param $url
Dries's avatar
   
Dries committed
1085
 *   The URL to verify.
Dries's avatar
   
Dries committed
1086
 * @param $absolute
Dries's avatar
   
Dries committed
1087
 *   Whether the URL is absolute (beginning with a scheme such as "http:").
Dries's avatar
   
Dries committed
1088
 * @return
Dries's avatar
   
Dries committed
1089
 *   TRUE if the URL is in a valid format.
Dries's avatar
   
Dries committed
1090
 */
Dries's avatar
   
Dries committed
1091
function valid_url($url, $absolute = FALSE) {
1092
  if ($absolute) {
1093
    return (bool)preg_match("
1094
      /^                                                      # Start at the beginning of the text
1095
      (?:ftp|https?|feed):\/\/                                # Look for ftp, http, https or feed schemes
1096
1097
1098
      (?:                                                     # Userinfo (optional) which is typically
        (?:(?:[\w\.\-\+!$&'\(\)*\+,;=]|%[0-9a-f]{2})+:)*      # a username or a username and password
        (?:[\w\.\-\+%!$&'\(\)*\+,;=]|%[0-9a-f]{2})+@          # combination
1099
      )?
1100
1101
1102
1103
1104
1105
      (?:
        (?:[a-z0-9\-\.]|%[0-9a-f]{2})+                        # A domain name or a IPv4 address
        |(?:\[(?:[0-9a-f]{0,4}:)*(?:[0-9a-f]{0,4})\])         # or a well formed IPv6 address
      )
      (?::[0-9]+)?                                            # Server port number (optional)
      (?:[\/|\?]
1106
        (?:[\w#!:\.\?\+=&@$'~*,;\/\(\)\[\]\-]|%[0-9a-f]{2})   # The path and query (optional)
1107
      *)?
1108
    $/xi", $url);
1109
1110
  }
  else {
1111
    return (bool)preg_match("/^(?:[\w#!:\.\?\+=&@$'~*,;\/\(\)\[\]\-]|%[0-9a-f]{2})+$/i", $url);
1112
  }
Dries's avatar
   
Dries committed
1113
1114
}

1115
1116
1117
1118
/**
 * @} End of "defgroup validation".
 */

Dries's avatar
   
Dries committed
1119
/**
1120
 * Register an event for the current visitor to the flood control mechanism.
Dries's avatar
   
Dries committed
1121
1122
 *
 * @param $name
1123
 *   The name of an event.
1124
1125
1126
1127
1128
 * @param $window
 *   Optional number of seconds before this event expires. Defaults to 3600 (1
 *   hour). Typically uses the same value as the flood_is_allowed() $window
 *   parameter. Expired events are purged on cron run to prevent the flood table
 *   from growing indefinitely.
1129
1130
 * @param $identifier
 *   Optional identifier (defaults to the current user's IP address).
Dries's avatar
   
Dries committed
1131
 */
1132
function flood_register_event($name, $window = 3600, $identifier = NULL) {
1133
1134
1135
  if (!isset($identifier)) {
    $identifier = ip_address();
  }
1136
1137
1138
  db_insert('flood')
    ->fields(array(
      'event' => $name,
1139
      'identifier' => $identifier,
1140
      'timestamp' => REQUEST_TIME,
1141
      'expiration' => REQUEST_TIME + $window,
1142
1143
    ))
    ->execute();
Dries's avatar
   
Dries committed
1144
1145
1146
}

/**
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
 * Make the flood control mechanism forget about an event for the current visitor.
 *
 * @param $name
 *   The name of an event.
 * @param $identifier
 *   Optional identifier (defaults to the current user's IP address).
 */
function flood_clear_event($name, $identifier = NULL) {
  if (!isset($identifier)) {
    $identifier = ip_address();
  }
  db_delete('flood')
    ->condition('event', $name)
    ->condition('identifier', $identifier)
    ->execute();
}

/**
1165
 * Checks whether user is allowed to proceed with the specified event.
1166
 *
1167
1168
1169
 * Events can have thresholds saying that each user can only do that event
 * a certain number of times in a time window. This function verifies that the
 * current user has not exceeded this threshold.
Dries's avatar
   
Dries committed
1170
1171
 *
 * @param $name
1172
 *   The unique name of the event.
1173
 * @param $threshold
1174
 *   The maximum number of times each user can do this event per time window.
1175
 * @param $window
1176
1177
 *   Number of seconds in the time window for this event (default is 3600
 *   seconds, or 1 hour).
1178
 * @param $identifier
1179
1180
 *   Unique identifier of the current user. Defaults to their IP address.
 *
Dries's avatar
   
Dries committed
1181
 * @return
1182
1183
 *   TRUE if the user is allowed to proceed. FALSE if they have exceeded the
 *   threshold and should not be allowed to proceed.
Dries's avatar
   
Dries committed
1184
 */
1185
1186
1187
1188
1189
function flood_is_allowed($name, $threshold, $window = 3600, $identifier = NULL) {
  if (!isset($identifier)) {
    $identifier = ip_address();
  }
  $number = db_query("SELECT COUNT(*) FROM {flood} WHERE event = :event AND identifier = :identifier AND timestamp > :timestamp", array(
1190
    ':event' => $name,
1191
1192
    ':identifier' => $identifier,
    ':timestamp' => REQUEST_TIME - $window))
1193
1194
    ->fetchField();
  return ($number < $threshold);
Dries's avatar
   
Dries committed
1195
1196
}

1197
1198
1199
1200
/**
 * @defgroup sanitization Sanitization functions
 * @{
 * Functions to sanitize values.
1201
1202
1203
 *
 * See http://drupal.org/writing-secure-code for information
 * on writing secure code.
1204
1205
 */

Dries's avatar
Dries committed
1206
/**
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230