common.inc 212 KB
Newer Older
Dries's avatar
 
Dries committed
1 2
<?php

3
use Drupal\Component\Utility\Crypt;
4
use Drupal\Component\Utility\Json;
5
use Drupal\Component\Utility\String;
6
use Drupal\Component\Utility\Tags;
7 8
use Drupal\Component\Utility\UrlValidator;
use Drupal\Component\Utility\Xss;
9
use Drupal\Core\Cache\Cache;
10
use Drupal\Core\Language\Language;
11
use Symfony\Component\DependencyInjection\Container;
12
use Symfony\Component\HttpFoundation\RedirectResponse;
13
use Symfony\Component\Yaml\Parser;
14 15
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\HttpFoundation\Request;
16
use Drupal\Component\PhpStorage\PhpStorageFactory;
17
use Drupal\Component\Utility\MapArray;
18
use Drupal\Component\Utility\NestedArray;
19
use Drupal\Component\Utility\Unicode;
20
use Drupal\Core\Cache\CacheBackendInterface;
21
use Drupal\Core\Datetime\DrupalDateTime;
22
use Drupal\Core\Database\Database;
23
use Drupal\Core\Routing\GeneratorNotInitializedException;
24
use Drupal\Core\SystemListingInfo;
25
use Drupal\Core\Template\Attribute;
26 27
use Zend\Feed\Writer\Writer;
use Zend\Feed\Reader\Reader;
28

Dries's avatar
 
Dries committed
29 30 31 32 33 34 35 36
/**
 * @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.
 */

37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64
/**
 * @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
 *
65
 * @}
66 67
 */

68 69 70
/**
 * Return status for saving which involved creating a new item.
 */
71
const SAVED_NEW = 1;
72 73 74 75

/**
 * Return status for saving which involved an update to an existing item.
 */
76
const SAVED_UPDATED = 2;
77 78 79 80

/**
 * Return status for saving which deleted an existing item.
 */
81
const SAVED_DELETED = 3;
82

83
/**
84
 * The default aggregation group for CSS files added to the page.
85
 */
86
const CSS_AGGREGATE_DEFAULT = 0;
87 88

/**
89
 * The default aggregation group for theme CSS files added to the page.
90
 */
91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116
const CSS_AGGREGATE_THEME = 100;

/**
 * The default weight for CSS rules that style HTML elements ("base" styles).
 */
const CSS_BASE = -200;

/**
 * The default weight for CSS rules that layout a page.
 */
const CSS_LAYOUT = -100;

/**
 * The default weight for CSS rules that style design components (and their associated states and skins.)
 */
const CSS_COMPONENT = 0;

/**
 * The default weight for CSS rules that style states and are not included with components.
 */
const CSS_STATE = 100;

/**
 * The default weight for CSS rules that style skins and are not included with components.
 */
const CSS_SKIN = 200;
117

118 119 120 121 122
/**
 * The default group for JavaScript settings added to the page.
 */
const JS_SETTING = -200;

123
/**
124
 * The default group for JavaScript and jQuery libraries added to the page.
125
 */
126
const JS_LIBRARY = -100;
127 128

/**
129
 * The default group for module JavaScript code added to the page.
130
 */
131
const JS_DEFAULT = 0;
132 133

/**
134
 * The default group for theme JavaScript code added to the page.
135
 */
136
const JS_THEME = 100;
137

138
/**
139 140 141
 * @defgroup block_caching Block Caching
 * @{
 * Constants that define each block's caching state.
142
 *
143 144 145 146 147 148 149 150 151 152
 * Modules specify how their blocks can be cached in their hook_block_info()
 * implementations. Caching can be turned off (DRUPAL_NO_CACHE), managed by the
 * module declaring the block (DRUPAL_CACHE_CUSTOM), or managed by the core
 * Block module. If the Block module is managing the cache, you can specify that
 * the block is the same for every page and user (DRUPAL_CACHE_GLOBAL), or that
 * it can change depending on the page (DRUPAL_CACHE_PER_PAGE) or by user
 * (DRUPAL_CACHE_PER_ROLE or DRUPAL_CACHE_PER_USER). Page and user settings can
 * be combined with a bitwise-binary or operator; for example,
 * DRUPAL_CACHE_PER_ROLE | DRUPAL_CACHE_PER_PAGE means that the block can change
 * depending on the user role or page it is on.
153
 *
154 155
 * The block cache is cleared when the 'content' cache tag is invalidated,
 * following the same pattern as the page cache (node, comment, user, taxonomy
156
 * added or updated...).
157 158 159 160 161
 *
 * Note that user 1 is excluded from block caching.
 */

/**
162 163 164 165 166 167 168
 * 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.
169
 */
170
const DRUPAL_NO_CACHE = -1;
171 172

/**
173 174
 * The block is handling its own caching in its hook_block_view().
 *
175 176
 * This setting is useful when time based expiration is needed or a site uses a
 * node access which invalidates standard block cache.
177
 */
178
const DRUPAL_CACHE_CUSTOM = -2;
179 180

/**
181 182 183 184
 * The block or element can change depending on the user's roles.
 *
 * This is the default setting for blocks, used when the block does not specify
 * anything.
185
 */
186
const DRUPAL_CACHE_PER_ROLE = 0x0001;
187 188

/**
189 190
 * The block or element can change depending on the user.
 *
191 192 193
 * 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.
 */
194
const DRUPAL_CACHE_PER_USER = 0x0002;
195 196 197 198

/**
 * The block or element can change depending on the page being viewed.
 */
199
const DRUPAL_CACHE_PER_PAGE = 0x0004;
200 201

/**
202
 * The block or element is the same for every user and page that it is visible.
203
 */
204
const DRUPAL_CACHE_GLOBAL = 0x0008;
205

206 207 208 209
/**
 * @} End of "defgroup block_caching".
 */

210 211 212 213 214 215 216 217 218
/**
 * The delimiter used to split plural strings.
 *
 * This is the ETX (End of text) character and is used as a minimal means to
 * separate singular and plural variants in source and translation text. It
 * was found to be the most compatible delimiter for the supported databases.
 */
const LOCALE_PLURAL_DELIMITER = "\03";

219
/**
220
 * Adds content to a specified region.
221 222
 *
 * @param $region
223
 *   Page region the content is added to.
224
 * @param $data
225
 *   Content to be added.
226
 */
227
function drupal_add_region_content($region = NULL, $data = NULL) {
228 229
  static $content = array();

230
  if (isset($region) && isset($data)) {
231 232 233 234 235 236
    $content[$region][] = $data;
  }
  return $content;
}

/**
237
 * Gets assigned content for a given region.
238 239
 *
 * @param $region
240 241
 *   A specified region to fetch content for. If NULL, all regions will be
 *   returned.
242
 * @param $delimiter
243
 *   Content to be inserted between imploded array elements.
244
 */
245 246
function drupal_get_region_content($region = NULL, $delimiter = ' ') {
  $content = drupal_add_region_content();
247 248
  if (isset($region)) {
    if (isset($content[$region]) && is_array($content[$region])) {
Steven Wittens's avatar
Steven Wittens committed
249
      return implode($delimiter, $content[$region]);
250
    }
251 252 253 254
  }
  else {
    foreach (array_keys($content) as $region) {
      if (is_array($content[$region])) {
Steven Wittens's avatar
Steven Wittens committed
255
        $content[$region] = implode($delimiter, $content[$region]);
256 257 258 259 260 261
      }
    }
    return $content;
  }
}

262
/**
263
 * Gets the name of the currently active installation profile.
264 265 266 267
 *
 * 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
268 269
 * table contains the name of the current profile, and we can call
 * variable_get() to determine what one is active.
270 271
 *
 * @return $profile
272
 *   The name of the installation profile.
273 274 275 276 277 278 279 280
 */
function drupal_get_profile() {
  global $install_state;

  if (isset($install_state['parameters']['profile'])) {
    $profile = $install_state['parameters']['profile'];
  }
  else {
281
    $profile = variable_get('install_profile', 'standard');
282 283 284 285 286 287
  }

  return $profile;
}


Dries's avatar
 
Dries committed
288
/**
289
 * Sets the breadcrumb trail for the current page.
Dries's avatar
 
Dries committed
290
 *
Dries's avatar
 
Dries committed
291 292 293
 * @param $breadcrumb
 *   Array of links, starting with "home" and proceeding up to but not including
 *   the current page.
294 295 296 297 298
 *
 * @deprecated This will be removed in 8.0. Instead, register a new breadcrumb
 *   builder service.
 *
 * @see Drupal\Core\Breadcrumb\BreadcrumbBuilderInterface
Kjartan's avatar
Kjartan committed
299
 */
Dries's avatar
 
Dries committed
300
function drupal_set_breadcrumb($breadcrumb = NULL) {
301
  $stored_breadcrumb = &drupal_static(__FUNCTION__);
Dries's avatar
 
Dries committed
302

303
  if (isset($breadcrumb)) {
Dries's avatar
 
Dries committed
304 305 306 307 308
    $stored_breadcrumb = $breadcrumb;
  }
  return $stored_breadcrumb;
}

Dries's avatar
Dries committed
309
/**
310
 * Adds output to the HEAD tag of the HTML page.
311
 *
312
 * This function can be called as long as the headers aren't sent. Pass no
313 314 315 316 317 318 319 320 321 322 323 324
 * 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 $data is not NULL.
 *
 * @return
 *   An array of all stored HEAD elements.
 *
325
 * @see drupal_pre_render_html_tag()
Dries's avatar
Dries committed
326
 */
327 328
function drupal_add_html_head($data = NULL, $key = NULL) {
  $stored_head = &drupal_static(__FUNCTION__);
Dries's avatar
Dries committed
329

330 331 332 333 334 335 336 337 338 339
  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
340 341 342 343
  }
  return $stored_head;
}

Dries's avatar
 
Dries committed
344
/**
345 346 347 348 349 350 351 352 353 354
 * 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.
  $elements['system_meta_content_type'] = array(
    '#type' => 'html_tag',
    '#tag' => 'meta',
    '#attributes' => array(
355
      'charset' => 'utf-8',
356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376
    ),
    // Security: This always has to be output first.
    '#weight' => -1000,
  );
  // Show Drupal and the major version number in the META GENERATOR tag.
  // Get the major version.
  list($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;
}

/**
377
 * Retrieves output to be displayed in the HEAD tag of the HTML page.
Dries's avatar
 
Dries committed
378
 */
Dries's avatar
Dries committed
379
function drupal_get_html_head() {
380 381 382
  $elements = drupal_add_html_head();
  drupal_alter('html_head', $elements);
  return drupal_render($elements);
Dries's avatar
Dries committed
383 384
}

385
/**
386
 * Adds a feed URL for the current page.
387
 *
388 389
 * This function can be called as long the HTML header hasn't been sent.
 *
390
 * @param $url
391
 *   An internal system path or a fully qualified external URL of the feed.
392
 * @param $title
393
 *   The title of the feed.
394
 */
395
function drupal_add_feed($url = NULL, $title = '') {
396
  $stored_feed_links = &drupal_static(__FUNCTION__, array());
397

398
  if (isset($url)) {
399
    $stored_feed_links[$url] = theme('feed_icon', array('url' => $url, 'title' => $title));
400

401 402 403 404 405 406 407 408
    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)),
    ));
409 410 411 412 413
  }
  return $stored_feed_links;
}

/**
414
 * Gets the feed URLs for the current page.
415 416
 *
 * @param $delimiter
417
 *   A delimiter to split feeds by.
418 419 420 421 422 423
 */
function drupal_get_feeds($delimiter = "\n") {
  $feeds = drupal_add_feed();
  return implode($feeds, $delimiter);
}

Dries's avatar
 
Dries committed
424
/**
425
 * @defgroup http_handling HTTP handling
Dries's avatar
 
Dries committed
426
 * @{
Dries's avatar
 
Dries committed
427
 * Functions to properly handle HTTP responses.
Dries's avatar
 
Dries committed
428 429
 */

430
/**
431
 * Processes a URL query parameter array to remove unwanted elements.
432 433
 *
 * @param $query
434
 *   (optional) An array to be processed. Defaults to $_GET.
435
 * @param $exclude
436
 *   (optional) A list of $query array keys to remove. Use "parent[child]" to
437
 *   exclude nested items.
438
 * @param $parent
439 440
 *   Internal use only. Used to build the $query array key for nested items.
 *
441
 * @return
442
 *   An array containing query parameters, which can be used for url().
443
 */
444
function drupal_get_query_parameters(array $query = NULL, array $exclude = array(), $parent = '') {
445 446 447 448 449 450 451 452 453 454 455
  // Set defaults, if none given.
  if (!isset($query)) {
    $query = $_GET;
  }
  // If $exclude is empty, there is nothing to filter.
  if (empty($exclude)) {
    return $query;
  }
  elseif (!$parent) {
    $exclude = array_flip($exclude);
  }
456

457
  $params = array();
458
  foreach ($query as $key => $value) {
459 460 461
    $string_key = ($parent ? $parent . '[' . $key . ']' : $key);
    if (isset($exclude[$string_key])) {
      continue;
462 463
    }

464 465 466 467 468
    if (is_array($value)) {
      $params[$key] = drupal_get_query_parameters($value, $exclude, $string_key);
    }
    else {
      $params[$key] = $value;
469
    }
470 471 472 473 474
  }

  return $params;
}

475
/**
476
 * Splits a URL-encoded query string into an array.
477 478 479 480 481
 *
 * @param $query
 *   The query string to split.
 *
 * @return
482
 *   An array of URL decoded couples $param_name => $value.
483 484 485 486 487 488
 */
function drupal_get_query_array($query) {
  $result = array();
  if (!empty($query)) {
    foreach (explode('&', $query) as $param) {
      $param = explode('=', $param);
489
      $result[$param[0]] = isset($param[1]) ? rawurldecode($param[1]) : '';
490 491 492 493 494
    }
  }
  return $result;
}

495
/**
496
 * Parses an array into a valid, rawurlencoded query string.
497
 *
498
 * @see \Drupal\Core\Routing\PathBasedGeneratorInterface::httpBuildQuery()
499
 * @see drupal_get_query_parameters()
500 501
 * @deprecated as of Drupal 8.0. Use
 *   Drupal::urlGenerator()->httpBuildQuery() instead.
502 503 504
 * @ingroup php_wrappers
 */
function drupal_http_build_query(array $query, $parent = '') {
505
  return Drupal::urlGenerator()->httpBuildQuery($query, $parent);
506 507
}

508
/**
509
 * Prepares a 'destination' URL query parameter for use with url().
510
 *
511 512 513 514
 * 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.
515
 *
516 517 518 519 520 521
 * @return
 *   An associative array containing the key:
 *   - destination: The path provided via the destination query string or, if
 *     not available, the current path.
 *
 * @see current_path()
522 523
 */
function drupal_get_destination() {
524 525 526 527 528 529
  $destination = &drupal_static(__FUNCTION__);

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

530
  if (isset($_GET['destination'])) {
531
    $destination = array('destination' => $_GET['destination']);
532 533
  }
  else {
534
    $path = current_path();
535
    $query = Drupal::urlGenerator()->httpBuildQuery(drupal_get_query_parameters());
536
    if ($query != '') {
537
      $path .= '?' . $query;
538
    }
539 540 541 542 543 544
    $destination = array('destination' => $path);
  }
  return $destination;
}

/**
545
 * Parses a system URL string into an associative array suitable for url().
546 547
 *
 * This function should only be used for URLs that have been generated by the
548 549
 * system, such as via url(). It should not be used for URLs that come from
 * external sources, or URLs that link to external resources.
550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601
 *
 * 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 $url, if existent.
 *
 * @see url()
 * @ingroup php_wrappers
 */
function drupal_parse_url($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 {
602 603 604 605 606
    // 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);
607 608 609 610 611 612 613 614 615 616 617 618
    if (isset($parts['query'])) {
      parse_str($parts['query'], $options['query']);
    }
    if (isset($parts['fragment'])) {
      $options['fragment'] = $parts['fragment'];
    }
  }

  return $options;
}

/**
619
 * Encodes a Drupal path for use in a URL.
620
 *
621
 * For aesthetic reasons slashes are not escaped.
622
 *
623 624
 * Note that url() takes care of calling this function, so a path passed to that
 * function should not be encoded in advance.
625 626
 *
 * @param $path
627
 *   The Drupal path to encode.
628 629
 */
function drupal_encode_path($path) {
630
  return str_replace('%2F', '/', rawurlencode($path));
631 632
}

633 634 635 636 637 638 639 640 641 642
/**
 * Determines if an external URL points to this Drupal installation.
 *
 * @param $url
 *   A string containing an external URL, such as "http://example.com/foo".
 *
 * @return
 *   TRUE if the URL has the same domain and base path.
 */
function _external_url_is_local($url) {
643 644
  $url_parts = parse_url($url);
  $base_host = parse_url($GLOBALS['base_url'], PHP_URL_HOST);
645

646 647 648 649
  if (!isset($url_parts['path'])) {
    return ($url_parts['host'] == $base_host);
  }
  else {
650 651 652 653
    // When comparing base paths, we need a trailing slash to make sure a
    // partial URL match isn't occuring. Since base_path() always returns with
    // a trailing slash, we don't need to add the trailing slash here.
    return ($url_parts['host'] == $base_host && stripos($url_parts['path'], base_path()) === 0);
654
  }
655 656
}

657 658 659 660 661 662 663
/**
 * Helper function for determining hosts excluded from needing a proxy.
 *
 * @return
 *   TRUE if a proxy should be used for this host.
 */
function _drupal_http_use_proxy($host) {
664
  $proxy_exceptions = settings()->get('proxy_exceptions', array('localhost', '127.0.0.1'));
665 666 667
  return !in_array(strtolower($host), $proxy_exceptions, TRUE);
}

Dries's avatar
 
Dries committed
668
/**
669
 * @} End of "defgroup http_handling".
Dries's avatar
 
Dries committed
670
 */
Dries's avatar
 
Dries committed
671

Kjartan's avatar
Kjartan committed
672
/**
Dries's avatar
 
Dries committed
673
 * @defgroup validation Input validation
Dries's avatar
 
Dries committed
674
 * @{
Dries's avatar
 
Dries committed
675
 * Functions to validate user input.
Kjartan's avatar
Kjartan committed
676 677
 */

678
/**
679
 * Verifies the syntax of the given e-mail address.
Dries's avatar
 
Dries committed
680
 *
681 682
 * This uses the
 * @link http://php.net/manual/filter.filters.validate.php PHP e-mail validation filter. @endlink
683
 *
Dries's avatar
 
Dries committed
684
 * @param $mail
685
 *   A string containing an e-mail address.
686
 *
Dries's avatar
 
Dries committed
687
 * @return
Dries's avatar
 
Dries committed
688
 *   TRUE if the address is in a valid format.
689
 */
Dries's avatar
 
Dries committed
690
function valid_email_address($mail) {
691
  return (bool)filter_var($mail, FILTER_VALIDATE_EMAIL);
692 693
}

Dries's avatar
 
Dries committed
694
/**
695
 * Verifies the syntax of the given URL.
Dries's avatar
 
Dries committed
696
 *
697 698
 * This function should only be used on actual URLs. It should not be used for
 * Drupal menu paths, which can contain arbitrary characters.
699
 * Valid values per RFC 3986.
Dries's avatar
 
Dries committed
700
 * @param $url
Dries's avatar
 
Dries committed
701
 *   The URL to verify.
Dries's avatar
 
Dries committed
702
 * @param $absolute
Dries's avatar
 
Dries committed
703
 *   Whether the URL is absolute (beginning with a scheme such as "http:").
704
 *
Dries's avatar
 
Dries committed
705
 * @return
Dries's avatar
 
Dries committed
706
 *   TRUE if the URL is in a valid format.
707 708
 *
 * @see \Drupal\Component\Utility\UrlValidator::isValid()
709 710
 *
 * @deprecated as of Drupal 8.0. Use UrlValidator::isValid() instead.
Dries's avatar
 
Dries committed
711
 */
Dries's avatar
 
Dries committed
712
function valid_url($url, $absolute = FALSE) {
713
  return UrlValidator::isValid($url, $absolute);
Dries's avatar
 
Dries committed
714 715
}

716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761
/**
 * Verifies that a number is a multiple of a given step.
 *
 * The implementation assumes it is dealing with IEEE 754 double precision
 * floating point numbers that are used by PHP on most systems.
 *
 * This is based on the number/range verification methods of webkit.
 *
 * @param $value
 *   The value that needs to be checked.
 * @param $step
 *   The step scale factor. Must be positive.
 * @param $offset
 *   (optional) An offset, to which the difference must be a multiple of the
 *   given step.
 *
 * @return bool
 *   TRUE if no step mismatch has occured, or FALSE otherwise.
 *
 * @see http://opensource.apple.com/source/WebCore/WebCore-1298/html/NumberInputType.cpp
 */
function valid_number_step($value, $step, $offset = 0.0) {
  $double_value = (double) abs($value - $offset);

  // The fractional part of a double has 53 bits. The greatest number that could
  // be represented with that is 2^53. If the given value is even bigger than
  // $step * 2^53, then dividing by $step will result in a very small remainder.
  // Since that remainder can't even be represented with a single precision
  // float the following computation of the remainder makes no sense and we can
  // safely ignore it instead.
  if ($double_value / pow(2.0, 53) > $step) {
    return TRUE;
  }

  // Now compute that remainder of a division by $step.
  $remainder = (double) abs($double_value - $step * round($double_value / $step));

  // $remainder is a double precision floating point number. Remainders that
  // can't be represented with single precision floats are acceptable. The
  // fractional part of a float has 24 bits. That means remainders smaller than
  // $step * 2^-24 are acceptable.
  $computed_acceptable_error = (double)($step / pow(2.0, 24));

  return $computed_acceptable_error >= $remainder || $remainder >= ($step - $computed_acceptable_error);
}

762 763 764 765
/**
 * @} End of "defgroup validation".
 */

766 767 768 769
/**
 * @defgroup sanitization Sanitization functions
 * @{
 * Functions to sanitize values.
770 771 772
 *
 * See http://drupal.org/writing-secure-code for information
 * on writing secure code.
773 774
 */

Dries's avatar
Dries committed
775
/**
776 777 778 779 780 781
 * Strips dangerous protocols (e.g. 'javascript:') from a URI.
 *
 * This function must be called for all URIs within user-entered input prior
 * to being output to an HTML attribute value. It is often called as part of
 * check_url() or filter_xss(), but those functions return an HTML-encoded
 * string, so this function can be called independently when the output needs to
782 783 784
 * be a plain-text string for passing to t(), l(),
 * Drupal\Core\Template\Attribute, or another function that will call
 * check_plain() separately.
785 786 787 788 789 790 791 792 793 794
 *
 * @param $uri
 *   A plain-text URI that might contain dangerous protocols.
 *
 * @return
 *   A plain-text URI stripped of dangerous protocols. As with all plain-text
 *   strings, this return value must not be output to an HTML page without
 *   check_plain() being called on it. However, it can be passed to functions
 *   expecting plain-text strings.
 *
795
 * @see \Drupal\Component\Utility\Url::stripDangerousProtocols()
796 797
 */
function drupal_strip_dangerous_protocols($uri) {
798
  return UrlValidator::stripDangerousProtocols($uri);
799 800 801
}

/**
802
 * Strips dangerous protocols from a URI and encodes it for output to HTML.
803 804 805 806 807 808 809
 *
 * @param $uri
 *   A plain-text URI that might contain dangerous protocols.
 *
 * @return
 *   A URI stripped of dangerous protocols and encoded for output to an HTML
 *   attribute value. Because it is already encoded, it should not be set as a
810 811 812 813 814
 *   value within a $attributes array passed to Drupal\Core\Template\Attribute,
 *   because Drupal\Core\Template\Attribute expects those values to be
 *   plain-text strings. To pass a filtered URI to
 *   Drupal\Core\Template\Attribute, call drupal_strip_dangerous_protocols()
 *   instead.
815
 *
816 817
 * @see \Drupal\Component\Utility\Url::stripDangerousProtocols()
 * @see \Drupal\Component\Utility\String::checkPlain()
Dries's avatar
Dries committed
818 819
 */
function check_url($uri) {
820
  return String::checkPlain(UrlValidator::stripDangerousProtocols($uri));
Dries's avatar
Dries committed
821 822
}

823
/**
824
 * Applies a very permissive XSS/HTML filter for admin-only use.
825 826 827 828 829 830 831
 *
 * Use only for fields where it is impractical to use the
 * whole filter system, but where some (mainly inline) mark-up
 * is desired (so check_plain() is not acceptable).
 *
 * Allows all tags that can be used inside an HTML body, save
 * for scripts and styles.
832 833 834 835 836 837 838 839
 *
 * @param string $string
 *   The string to apply the filter to.
 *
 * @return string
 *   The filtered string.
 *
 * @see \Drupal\Component\Utility\Xss::filterAdmin()
840 841
 */
function filter_xss_admin($string) {
842
  return Xss::filterAdmin($string);
843 844 845
}

/**
846
 * Filters HTML to prevent cross-site-scripting (XSS) vulnerabilities.
847
 *
848 849
 * Based on kses by Ulf Harnhammar, see http://sourceforge.net/projects/kses.
 * For examples of various XSS attacks, see: http://ha.ckers.org/xss.html.
850 851
 *
 * This code does four things:
852 853 854 855 856
 * - Removes characters and constructs that can trick browsers.
 * - Makes sure all HTML entities are well-formed.
 * - Makes sure all HTML tags and attributes are well-formed.
 * - Makes sure no HTML tags contain URLs with a disallowed protocol (e.g.
 *   javascript:).
857 858
 *
 * @param $string
859 860
 *   The string with raw HTML in it. It will be stripped of everything that can
 *   cause an XSS attack.
861 862
 * @param $allowed_tags
 *   An array of allowed tags.
863 864 865 866 867
 *
 * @return
 *   An XSS safe version of $string, or an empty string if $string is not
 *   valid UTF-8.
 *
868 869
 * @see \Drupal\Component\Utility\Xss::filter()
 *
870
 * @ingroup sanitization
871 872
 */
function filter_xss($string, $allowed_tags = array('a', 'em', 'strong', 'cite', 'blockquote', 'code', 'ul', 'ol', 'li', 'dl', 'dt', 'dd')) {
873
  return Xss::filter($string, $allowed_tags);
874 875 876
}

/**
877
 * Processes an HTML attribute value and strips dangerous protocols from URLs.
878
 *
879
 * @param string $string
880
 *   The string with the attribute value.
881
 *
882
 * @return string
883
 *   Cleaned up and HTML-escaped version of $string.
884 885
 *
 * @see \Drupal\Component\Utility\Url::filterBadProtocol()
886
 */
887 888
function filter_xss_bad_protocol($string) {
  return UrlValidator::filterBadProtocol($string);
889 890 891 892 893 894
}

/**
 * @} End of "defgroup sanitization".
 */

Dries's avatar
 
Dries committed
895
/**
Dries's avatar
 
Dries committed
896
 * @defgroup format Formatting
Dries's avatar
 
Dries committed
897
 * @{
Dries's avatar
 
Dries committed
898
 * Functions to format numbers, strings, dates, etc.
Dries's avatar
 
Dries committed
899 900
 */

Dries's avatar
 
Dries committed
901 902 903 904 905
/**
 * Formats an RSS channel.
 *
 * Arbitrary elements may be added using the $args associative array.
 */
906
function format_rss_channel($title, $link, $description, $items, $langcode = NULL, $args = array()) {
907
  $langcode = $langcode ? $langcode : language(Language::TYPE_CONTENT)->langcode;
Dries's avatar
 
Dries committed
908

Dries's avatar
Dries committed
909
  $output = "<channel>\n";
910 911
  $output .= ' <title>' . check_plain($title) . "</title>\n";
  $output .= ' <link>' . check_url($link) . "</link>\n";
912 913 914 915

  // The RSS 2.0 "spec" doesn't indicate HTML can be used in the description.
  // We strip all HTML tags, but need to prevent double encoding from properly
  // escaped source data (such as &amp becoming &amp;amp;).
916 917
  $output .= ' <description>' . check_plain(decode_entities(strip_tags($description))) . "</description>\n";
  $output .= ' <language>' . check_plain($langcode) . "</language>\n";
918
  $output .= format_xml_elements($args);
Dries's avatar
 
Dries committed
919 920 921 922 923 924
  $output .= $items;
  $output .= "</channel>\n";

  return $output;
}

Dries's avatar
 
Dries committed
925
/**
926
 * Formats a single RSS item.
Dries's avatar
 
Dries committed
927 928 929
 *
 * Arbitrary elements may be added using the $args associative array.
 */
Dries's avatar
 
Dries committed
930
function format_rss_item($title, $link, $description, $args = array()) {
Dries's avatar
Dries committed
931
  $output = "<item>\n";
932 933 934
  $output .= ' <title>' . check_plain($title) . "</title>\n";
  $output .= ' <link>' . check_url($link) . "</link>\n";
  $output .= ' <description>' . check_plain($description) . "</description>\n";
935 936 937 938 939 940 941
  $output .= format_xml_elements($args);
  $output .= "</item>\n";

  return $output;
}

/**
942
 * Formats XML elements.
943 944
 *
 * @param $array
945
 *   An array where each item represents an element and is either a:
946 947 948 949 950 951 952 953 954 955
 *   - (key => value) pair (<key>value</key>)
 *   - Associative array with fields:
 *     - 'key': element name
 *     - 'value': element contents
 *     - 'attributes': associative array of element attributes
 *
 * In both cases, 'value' can be a simple string, or it can be another array
 * with the same format as $array itself for nesting.
 */
function format_xml_elements($array) {
956
  $output = '';
957 958
  foreach ($array as $key => $value) {
    if (is_numeric($key)) {
Dries's avatar
 
Dries committed
959
      if ($value['key']) {
960
        $output .= ' <' . $value['key'];
961
        if (isset($value['attributes']) && is_array($value['attributes'])) {
962
          $output .= new Attribute($value['attributes']);
Dries's avatar
 
Dries committed
963 964
        }

965
        if (isset($value['value']) && $value['value'] != '') {
966
          $output .= '>' . (is_array($value['value']) ? format_xml_elements($value['value']) : check_plain($value['value'])) . '</' . $value['key'] . ">\n";
Dries's avatar
 
Dries committed
967 968 969 970 971 972 973
        }
        else {
          $output .= " />\n";
        }
      }
    }
    else {
974
      $output .= ' <' . $key . '>' . (is_array($value) ? format_xml_elements($value) : check_plain($value)) . "</$key>\n";
Dries's avatar
 
Dries committed
975
    }
Dries's avatar
 
Dries committed
976
  }
Dries's avatar
 
Dries committed
977 978 979
  return $output;
}

Dries's avatar
 
Dries committed
980
/**
981
 * Formats a string containing a count of items.
Dries's avatar
 
Dries committed
982
 *
Dries's avatar
 
Dries committed
983
 * This function ensures that the string is pluralized correctly. Since t() is
984 985
 * called by this function, make sure not to pass already-localized strings to
 * it.
Dries's avatar
 
Dries committed
986
 *
987 988 989 990 991 992 993 994 995 996
 * For example:
 * @code
 *   $output = format_plural($node->comment_count, '1 comment', '@count comments');
 * @endcode
 *
 * Example with additional replacements:
 * @code
 *   $output = format_plural($update_count,
 *     'Changed the content type of 1 post from %old-type to %new-type.',
 *     'Changed the content type of @count posts from %old-type to %new-type.',
997
 *     array('%old-type' => $info->old_type, '%new-type' => $info->new_type));
998 999
 * @endcode
 *
Dries's avatar
 
Dries committed
1000 1001 1002
 * @param $count
 *   The item count to display.
 * @param $singular
1003 1004 1005
 *   The string for the singular case. Make sure it is clear this is singular,
 *   to ease translation (e.g. use "1 new comment" instead of "1 new"). Do not
 *   use @count in the singular string.
Dries's avatar
 
Dries committed
1006
 * @param $plural
1007 1008 1009
 *   The string for the plural case. Make sure it is clear this is plural, to
 *   ease translation. Use @count in place of the item count, as in
 *   "@count new comments".
1010
 * @param $args
1011
 *   An associative array of replacements to make after translation. Instances
1012
 *   of any key in this array are replaced with the corresponding value.
1013 1014 1015
 *   Based on the first character of the key, the value is escaped and/or
 *   themed. See format_string(). Note that you do not need to include @count
 *   in this array; this replacement is done automatically for the plural case.
1016
 * @param $options
1017 1018
 *   An associative array of additional options. See t() for allowed keys.
 *
Dries's avatar
 
Dries committed
1019 1020
 * @return
 *   A translated string.
1021 1022 1023
 *
 * @see t()
 * @see format_string()
Dries's avatar
 
Dries committed
1024
 */
1025
function format_plural($count, $singular, $plural, array $args = array(), array $options = array()) {
1026
  $args['@count'] = $count;
1027 1028 1029 1030 1031 1032 1033
  // Join both forms to search a translation.
  $tranlatable_string = implode(LOCALE_PLURAL_DELIMITER, array($singular, $plural));
  // Translate as usual.
  $translated_strings = t($tranlatable_string, $args, $options);
  // Split joined translation strings into array.
  $translated_array = explode(LOCALE_PLURAL_DELIMITER, $translated_strings);

1034
  if ($count == 1) {
1035
    return $translated_array[0];
1036
  }
Dries's avatar
 
Dries committed
1037

1038
  // Get the plural index through the gettext formula.
1039
  // @todo implement static variable to minimize function_exists() usage.
1040
  $index = (function_exists('locale_get_plural')) ? locale_get_plural($count, isset($options['langcode']) ? $options['langcode'] : NULL) : -1;
1041 1042 1043
  if ($index == 0) {
    // Singular form.
    return $translated_array[0];
Dries's avatar
 
Dries committed
1044 1045
  }
  else {
1046 1047 1048 1049 1050 1051 1052 1053 1054
    if (isset($translated_array[$index])) {
      // N-th plural form.
      return $translated_array[$index];
    }
    else {
      // If the index cannot be computed or there's no translation, use
      // the second plural form as a fallback (which allows for most flexiblity
      // with the replaceable @count value).
      return $translated_array[1];
Dries's avatar
 
Dries committed
1055 1056
    }
  }
Dries's avatar
 
Dries committed
1057 1058
}

1059
/**
1060
 * Parses a given byte count.
1061 1062
 *
 * @param $size
1063 1064
 *   A size expressed as a number of bytes with optional SI or IEC binary unit
 *   prefix (e.g. 2, 3K, 5MB, 10G, 6GiB, 8 bytes, 9mbytes).
1065
 *
1066
 * @return
1067
 *   An integer representation of the size in bytes.
1068 1069
 */
function parse_size($size) {
1070 1071 1072 1073 1074 1075 1076 1077
  $unit = preg_replace('/[^bkmgtpezy]/i', '', $size); // Remove the non-unit characters from the size.
  $size = preg_replace('/[^0-9\.]/', '', $size); // Remove the non-numeric characters from the size.
  if ($unit) {
    // Find the position of the unit in the ordered string which is the power of magnitude to multiply a kilobyte by.
    return round($size * pow(DRUPAL_KILOBYTE, stripos('bkmgtpezy', $unit[0])));
  }
  else {
    return round($size);
1078 1079 1080
  }
}

Dries's avatar
 
Dries committed
1081
/**
1082
 * Generates a string representation for the given byte count.
Dries's avatar
 
Dries committed
1083
 *
Dries's avatar
 
Dries committed
1084
 * @param $size
1085
 *   A size in bytes.
1086
 * @param $langcode
1087 1088
 *   Optional language code to translate to a language other than what is used
 *   to display the page.
1089
 *
Dries's avatar
 
Dries committed
1090 1091
 * @return
 *   A translated string representation of the size.
Dries's avatar
 
Dries committed
1092
 */
1093
function format_size($size, $langcode = NULL) {
1094
  if ($size < DRUPAL_KILOBYTE) {
1095
    return format_plural($size, '1 byte', '@count bytes', array(), array('langcode' => $langcode));
Dries's avatar
 
Dries committed
1096
  }
1097
  else {
1098
    $size = $size / DRUPAL_KILOBYTE; // Convert bytes to kilobytes.
1099
    $units = array(
1100 1101 1102 1103 1104 1105 1106 1107
      t('@size KB', array(), array('langcode' => $langcode)),
      t('@size MB', array(), array('langcode' => $langcode)),
      t('@size GB', array(), array('langcode' => $langcode)),
      t('@size TB', array(), array('langcode' => $langcode)),
      t('@size PB', array(), array('langcode' => $langcode)),
      t('@size EB', array(), array('langcode' => $langcode)),
      t('@size ZB', array(), array('langcode' => $langcode)),
      t('@size YB', array(), array('langcode' => $langcode)),
1108 1109
    );
    foreach ($units as $unit) {
1110 1111
      if (round($size, 2) >= DRUPAL_KILOBYTE) {
        $size = $size / DRUPAL_KILOBYTE;
1112 1113 1114 1115
      }
      else {
        break;
      }
1116
    }
1117
    return str_replace('@size', round($size, 2), $unit);
Dries's avatar
 
Dries committed
1118 1119 1120
  }
}

Dries's avatar
 
Dries committed
1121
/**
1122
 * Formats a time interval with the requested granularity.
Dries's avatar
 
Dries committed
1123
 *
1124
 * @param $interval
Dries's avatar
 
Dries committed
1125 1126 1127
 *   The length of the interval in seconds.
 * @param $granularity
 *   How many different units to display in the string.
1128 1129 1130
 * @param $langcode
 *   Optional language code to translate to a language other than
 *   what is used to display the page.
1131
 *
Dries's avatar
 
Dries committed