common.inc 102 KB
Newer Older
Dries's avatar
Dries committed
1
<?php
2
// $Id$
Dries's avatar
Dries committed
3

4 5 6 7 8 9 10 11
/**
 * @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.
 */

12 13 14 15 16 17 18 19 20 21 22 23 24 25 26
/**
 * 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);

27 28 29 30 31 32 33 34 35
/**
 * Set content for a specified region.
 *
 * @param $region
 *   Page region the content is assigned to.
 *
 * @param $data
 *   Content to be set.
 */
36
function drupal_set_content($region = NULL, $data = NULL) {
37 38 39 40 41 42 43 44 45 46 47 48
  static $content = array();

  if (!is_null($region) && !is_null($data)) {
    $content[$region][] = $data;
  }
  return $content;
}

/**
 * Get assigned content.
 *
 * @param $region
49
 *   A specified region to fetch content for. If NULL, all regions will be returned.
50 51 52 53
 *
 * @param $delimiter
 *   Content to be inserted between exploded array elements.
 */
54
function drupal_get_content($region = NULL, $delimiter = ' ') {
55
  $content = drupal_set_content();
56 57
  if (isset($region)) {
    if (isset($content[$region]) && is_array($content[$region])) {
Steven Wittens's avatar
Steven Wittens committed
58
      return implode($delimiter, $content[$region]);
59
    }
60 61 62 63
  }
  else {
    foreach (array_keys($content) as $region) {
      if (is_array($content[$region])) {
Steven Wittens's avatar
Steven Wittens committed
64
        $content[$region] = implode($delimiter, $content[$region]);
65 66 67 68 69 70
      }
    }
    return $content;
  }
}

71
/**
72
 * Set the breadcrumb trail for the current page.
73
 *
74 75 76
 * @param $breadcrumb
 *   Array of links, starting with "home" and proceeding up to but not including
 *   the current page.
77
 */
78 79 80
function drupal_set_breadcrumb($breadcrumb = NULL) {
  static $stored_breadcrumb;

81
  if (!is_null($breadcrumb)) {
82 83 84 85 86
    $stored_breadcrumb = $breadcrumb;
  }
  return $stored_breadcrumb;
}

87 88 89
/**
 * Get the breadcrumb trail for the current page.
 */
90 91 92
function drupal_get_breadcrumb() {
  $breadcrumb = drupal_set_breadcrumb();

93
  if (is_null($breadcrumb)) {
94 95 96 97 98 99
    $breadcrumb = menu_get_active_breadcrumb();
  }

  return $breadcrumb;
}

Dries's avatar
Dries committed
100
/**
101
 * Add output to the head tag of the HTML page.
102
 * This function can be called as long the headers aren't sent.
Dries's avatar
Dries committed
103 104
 */
function drupal_set_html_head($data = NULL) {
105
  static $stored_head = '';
Dries's avatar
Dries committed
106 107

  if (!is_null($data)) {
108
    $stored_head .= $data ."\n";
Dries's avatar
Dries committed
109 110 111 112
  }
  return $stored_head;
}

113 114 115
/**
 * Retrieve output to be displayed in the head tag of the HTML page.
 */
Dries's avatar
Dries committed
116
function drupal_get_html_head() {
117
  $output = "<meta http-equiv=\"Content-Type\" content=\"text/html; charset=utf-8\" />\n";
Dries's avatar
Dries committed
118 119 120
  return $output . drupal_set_html_head();
}

121
/**
122
 * Reset the static variable which holds the aliases mapped for this request.
123
 */
124 125
function drupal_clear_path_cache() {
  drupal_lookup_path('wipe');
126
}
127

Dries's avatar
Dries committed
128
/**
129
 * Set an HTTP response header for the current page.
130 131 132
 *
 * Note: when sending a Content-Type header, always include a 'charset' type
 * too. This is necessary to avoid security bugs (e.g. UTF-7 XSS).
Dries's avatar
Dries committed
133 134
 */
function drupal_set_header($header = NULL) {
135
  // We use an array to guarantee there are no leading or trailing delimiters.
136
  // Otherwise, header('') could get called when serving the page later, which
137 138
  // ends HTTP headers prematurely on some PHP versions.
  static $stored_headers = array();
Dries's avatar
Dries committed
139

140
  if (strlen($header)) {
Dries's avatar
Dries committed
141
    header($header);
142
    $stored_headers[] = $header;
Dries's avatar
Dries committed
143
  }
144
  return implode("\n", $stored_headers);
Dries's avatar
Dries committed
145 146
}

147 148 149
/**
 * Get the HTTP response headers for the current page.
 */
Dries's avatar
Dries committed
150 151 152 153
function drupal_get_headers() {
  return drupal_set_header();
}

154
/**
155 156 157 158
 * Add a feed URL for the current page.
 *
 * @param $url
 *   The url for the feed
159 160
 * @param $title
 *   The title of the feed
161
 */
162
function drupal_add_feed($url = NULL, $title = '') {
163 164
  static $stored_feed_links = array();

165
  if (!is_null($url) && !isset($stored_feed_links[$url])) {
166
    $stored_feed_links[$url] = theme('feed_icon', $url, $title);
167 168 169 170 171

    drupal_add_link(array('rel' => 'alternate',
                          'type' => 'application/rss+xml',
                          'title' => $title,
                          'href' => $url));
172 173 174 175 176 177 178 179 180 181 182 183 184 185 186
  }
  return $stored_feed_links;
}

/**
 * Get the feed URLs for the current page.
 *
 * @param $delimiter
 *   The delimiter to split feeds by
 */
function drupal_get_feeds($delimiter = "\n") {
  $feeds = drupal_add_feed();
  return implode($feeds, $delimiter);
}

187 188 189
/**
 * @name HTTP handling
 * @{
190
 * Functions to properly handle HTTP responses.
191 192
 */

193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208
/**
 * Parse an array into a valid urlencoded query string.
 *
 * @param $query
 *   The array to be processed e.g. $_GET
 * @param $exclude
 *   The array filled with keys to be excluded. Use parent[child] to exclude nested items.
 * @param $parent
 *   Should not be passed, only used in recursive calls
 * @return
 *   urlencoded string which can be appended to/as the URL query string
 */
function drupal_query_string_encode($query, $exclude = array(), $parent = '') {
  $params = array();

  foreach ($query as $key => $value) {
209
    $key = drupal_urlencode($key);
210
    if ($parent) {
211
      $key = $parent .'['. $key .']';
212 213
    }

214
    if (in_array($key, $exclude)) {
215 216 217 218 219 220 221
      continue;
    }

    if (is_array($value)) {
      $params[] = drupal_query_string_encode($value, $exclude, $key);
    }
    else {
222
      $params[] = $key .'='. drupal_urlencode($value);
223 224 225 226 227 228
    }
  }

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

229 230
/**
 * Prepare a destination query string for use in combination with
231 232 233
 * drupal_goto(). 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
234
 * is returned. As such, a destination can persist across multiple
235
 * pages.
236 237 238 239
 *
 * @see drupal_goto()
 */
function drupal_get_destination() {
240
  if (isset($_REQUEST['destination'])) {
241 242 243
    return 'destination='. urlencode($_REQUEST['destination']);
  }
  else {
244 245
    // Use $_GET here to retrieve the original path in source form.
    $path = isset($_GET['q']) ? $_GET['q'] : '';
246 247 248
    $query = drupal_query_string_encode($_GET, array('q'));
    if ($query != '') {
      $path .= '?'. $query;
249
    }
250
    return 'destination='. urlencode($path);
251 252 253
  }
}

254
/**
255
 * Send the user to a different Drupal page.
256
 *
257 258
 * This issues an on-site HTTP redirect. The function makes sure the redirected
 * URL is formatted correctly.
259
 *
260
 * Usually the redirected URL is constructed from this function's input
261
 * parameters. However you may override that behavior by setting a
262 263
 * <em>destination</em> in either the $_REQUEST-array (i.e. by using
 * the query string of an URI) or the $_REQUEST['edit']-array (i.e. by
264 265
 * using a hidden form field). This is used to direct the user back to
 * the proper page after completing a form. For example, after editing
266
 * a post on the 'admin/content/node'-page or after having logged on using the
267
 * 'user login'-block in a sidebar. The function drupal_get_destination()
268 269
 * can be used to help set the destination URL.
 *
270 271 272 273 274 275 276 277
 * It is advised to use drupal_goto() instead of PHP's header(), because
 * drupal_goto() will append the user's session ID to the URI when PHP is
 * compiled with "--enable-trans-sid".
 *
 * This function ends the request; use it rather than a print theme('page')
 * statement in your menu callback.
 *
 * @param $path
278
 *   A Drupal path or a full URL.
279 280 281 282
 * @param $query
 *   The query string component, if any.
 * @param $fragment
 *   The destination fragment identifier (named anchor).
283 284 285 286 287 288 289 290 291 292 293
 * @param $http_response_code
 *   Valid values for an actual "goto" as per RFC 2616 section 10.3 are:
 *   - 301 Moved Permanently (the recommended value for most redirects)
 *   - 302 Found (default in Drupal and PHP, sometimes used for spamming search
 *         engines)
 *   - 303 See Other
 *   - 304 Not Modified
 *   - 305 Use Proxy
 *   - 307 Temporary Redirect (an alternative to "503 Site Down for Maintenance")
 *   Note: Other values are defined by RFC 2616, but are rarely used and poorly
 *         supported.
294
 * @see drupal_get_destination()
295
 */
296
function drupal_goto($path = '', $query = NULL, $fragment = NULL, $http_response_code = 302) {
297
  if (isset($_REQUEST['destination'])) {
298
    extract(parse_url(urldecode($_REQUEST['destination'])));
299
  }
300
  else if (isset($_REQUEST['edit']['destination'])) {
301
    extract(parse_url(urldecode($_REQUEST['edit']['destination'])));
302 303
  }

304
  $url = url($path, array('query' => $query, 'fragment' => $fragment, 'absolute' => TRUE));
305

306 307 308
  // Before the redirect, allow modules to react to the end of the page request.
  module_invoke_all('exit', $url);

309 310 311 312 313 314 315
  // Here we register header() to be called after exit(). Because
  // session_write_close() was registered before header() all session
  // data will be written to the database before the header is sent to the
  // browser.
  register_shutdown_function('header', "Location: $url", TRUE, $http_response_code);
  
  // Make sure none of the code below the drupal_goto() call gets executed. 
316 317 318
  exit();
}

319
/**
320
 * Generates a site off-line message
321 322
 */
function drupal_site_offline() {
323
  drupal_maintenance_theme();
324
  drupal_set_header('HTTP/1.1 503 Service unavailable');
325
  drupal_set_title(t('Site off-line'));
326
  print theme('maintenance_page', filter_xss_admin(variable_get('site_offline_message',
327
    t('@site is currently under maintenance. We should be back shortly. Thank you for your patience.', array('@site' => variable_get('site_name', 'Drupal'))))));
328 329
}

330 331 332
/**
 * Generates a 404 error if the request can not be handled.
 */
333
function drupal_not_found() {
334
  drupal_set_header('HTTP/1.1 404 Not Found');
335

336
  watchdog('page not found', check_plain($_GET['q']), NULL, WATCHDOG_WARNING);
337

338 339 340 341 342
  // Keep old path for reference
  if (!isset($_REQUEST['destination'])) {
    $_REQUEST['destination'] = $_GET['q'];
  }

343
  $path = drupal_get_normal_path(variable_get('site_404', ''));
drumm's avatar
drumm committed
344
  if ($path && $path != $_GET['q']) {
345 346 347
    // Set the active item in case there are tabs to display, or other
    // dependencies on the path.
    menu_set_active_item($path);
348
    $return = menu_execute_active_handler($path);
349
  }
350

drumm's avatar
drumm committed
351 352
  if (empty($return)) {
    drupal_set_title(t('Page not found'));
353
    $return = '';
354
  }
355 356
  // To conserve CPU and bandwidth, omit the blocks
  print theme('page', $return, FALSE);
357
}
358

359 360 361 362
/**
 * Generates a 403 error if the request is not allowed.
 */
function drupal_access_denied() {
363
  drupal_set_header('HTTP/1.1 403 Forbidden');
364
  watchdog('access denied', check_plain($_GET['q']), NULL, WATCHDOG_WARNING);
365

drumm's avatar
drumm committed
366
// Keep old path for reference
367 368 369 370
  if (!isset($_REQUEST['destination'])) {
    $_REQUEST['destination'] = $_GET['q'];
  }

371
  $path = drupal_get_normal_path(variable_get('site_403', ''));
drumm's avatar
drumm committed
372
  if ($path && $path != $_GET['q']) {
373 374 375
    // Set the active item in case there are tabs to display, or other
    // dependencies on the path.
    menu_set_active_item($path);
376
    $return = menu_execute_active_handler($path);
377
  }
378

drumm's avatar
drumm committed
379 380 381
  if (empty($return)) {
    drupal_set_title(t('Access denied'));
    $return = t('You are not authorized to access this page.');
382
  }
383
  print theme('page', $return);
384 385
}

386
/**
387
 * Perform an HTTP request.
388
 *
389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405
 * This is a flexible and powerful HTTP client implementation. Correctly handles
 * GET, POST, PUT or any other HTTP requests. Handles redirects.
 *
 * @param $url
 *   A string containing a fully qualified URI.
 * @param $headers
 *   An array containing an HTTP header => value pair.
 * @param $method
 *   A string defining the HTTP request to use.
 * @param $data
 *   A string containing data to include in the request.
 * @param $retry
 *   An integer representing how many times to retry the request in case of a
 *   redirect.
 * @return
 *   An object containing the HTTP request headers, response code, headers,
 *   data, and redirect status.
406 407
 */
function drupal_http_request($url, $headers = array(), $method = 'GET', $data = NULL, $retry = 3) {
408
  $result = new stdClass();
409

410
  // Parse the URL, and make sure we can handle the schema.
411
  $uri = parse_url($url);
412

413 414
  switch ($uri['scheme']) {
    case 'http':
415
      $port = isset($uri['port']) ? $uri['port'] : 80;
416
      $host = $uri['host'] . ($port != 80 ? ':'. $port : '');
417
      $fp = @fsockopen($uri['host'], $port, $errno, $errstr, 15);
418 419
      break;
    case 'https':
420
      // Note: Only works for PHP 4.3 compiled with OpenSSL.
421
      $port = isset($uri['port']) ? $uri['port'] : 443;
422
      $host = $uri['host'] . ($port != 443 ? ':'. $port : '');
423
      $fp = @fsockopen('ssl://'. $uri['host'], $port, $errno, $errstr, 20);
424 425
      break;
    default:
426
      $result->error = 'invalid schema '. $uri['scheme'];
427 428 429
      return $result;
  }

430
  // Make sure the socket opened properly.
431
  if (!$fp) {
432 433 434 435
    // When a network error occurs, we make sure that it is a negative
    // number so it can clash with the HTTP status codes.
    $result->code = -$errno;
    $result->error = trim($errstr);
436 437 438
    return $result;
  }

439
  // Construct the path to act on.
440 441
  $path = isset($uri['path']) ? $uri['path'] : '/';
  if (isset($uri['query'])) {
442
    $path .= '?'. $uri['query'];
443 444
  }

445
  // Create HTTP request.
446
  $defaults = array(
447 448 449 450
    // RFC 2616: "non-standard ports MUST, default ports MAY be included".
    // We don't add the port to prevent from breaking rewrite rules checking
    // the host that do not take into account the port number.
    'Host' => "Host: $host",
451
    'User-Agent' => 'User-Agent: Drupal (+http://drupal.org/)',
452
    'Content-Length' => 'Content-Length: '. strlen($data)
453 454 455
  );

  foreach ($headers as $header => $value) {
456
    $defaults[$header] = $header .': '. $value;
457 458
  }

459
  $request = $method .' '. $path ." HTTP/1.0\r\n";
460 461 462
  $request .= implode("\r\n", $defaults);
  $request .= "\r\n\r\n";
  if ($data) {
463
    $request .= $data ."\r\n";
464 465 466 467 468 469
  }
  $result->request = $request;

  fwrite($fp, $request);

  // Fetch response.
470
  $response = '';
471 472
  while (!feof($fp) && $chunk = fread($fp, 1024)) {
    $response .= $chunk;
473 474 475 476
  }
  fclose($fp);

  // Parse response.
477 478
  list($split, $result->data) = explode("\r\n\r\n", $response, 2);
  $split = preg_split("/\r\n|\n|\r/", $split);
479

480
  list($protocol, $code, $text) = explode(' ', trim(array_shift($split)), 3);
481 482 483
  $result->headers = array();

  // Parse headers.
484
  while ($line = trim(array_shift($split))) {
485
    list($header, $value) = explode(':', $line, 2);
486 487 488 489 490 491 492 493
    if (isset($result->headers[$header]) && $header == 'Set-Cookie') {
      // RFC 2109: the Set-Cookie response header comprises the token Set-
      // Cookie:, followed by a comma-separated list of one or more cookies.
      $result->headers[$header] .= ','. trim($value);
    }
    else {
      $result->headers[$header] = trim($value);
    }
494 495 496 497 498 499 500 501 502 503
  }

  $responses = array(
    100 => 'Continue', 101 => 'Switching Protocols',
    200 => 'OK', 201 => 'Created', 202 => 'Accepted', 203 => 'Non-Authoritative Information', 204 => 'No Content', 205 => 'Reset Content', 206 => 'Partial Content',
    300 => 'Multiple Choices', 301 => 'Moved Permanently', 302 => 'Found', 303 => 'See Other', 304 => 'Not Modified', 305 => 'Use Proxy', 307 => 'Temporary Redirect',
    400 => 'Bad Request', 401 => 'Unauthorized', 402 => 'Payment Required', 403 => 'Forbidden', 404 => 'Not Found', 405 => 'Method Not Allowed', 406 => 'Not Acceptable', 407 => 'Proxy Authentication Required', 408 => 'Request Time-out', 409 => 'Conflict', 410 => 'Gone', 411 => 'Length Required', 412 => 'Precondition Failed', 413 => 'Request Entity Too Large', 414 => 'Request-URI Too Large', 415 => 'Unsupported Media Type', 416 => 'Requested range not satisfiable', 417 => 'Expectation Failed',
    500 => 'Internal Server Error', 501 => 'Not Implemented', 502 => 'Bad Gateway', 503 => 'Service Unavailable', 504 => 'Gateway Time-out', 505 => 'HTTP Version not supported'
  );
  // RFC 2616 states that all unknown HTTP codes must be treated the same as
504
  // the base code in their class.
505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531
  if (!isset($responses[$code])) {
    $code = floor($code / 100) * 100;
  }

  switch ($code) {
    case 200: // OK
    case 304: // Not modified
      break;
    case 301: // Moved permanently
    case 302: // Moved temporarily
    case 307: // Moved temporarily
      $location = $result->headers['Location'];

      if ($retry) {
        $result = drupal_http_request($result->headers['Location'], $headers, $method, $data, --$retry);
        $result->redirect_code = $result->code;
      }
      $result->redirect_url = $location;

      break;
    default:
      $result->error = $text;
  }

  $result->code = $code;
  return $result;
}
532 533 534
/**
 * @} End of "HTTP handling".
 */
535

536
/**
537 538
 * Log errors as defined by administrator
 * Error levels:
539 540
 *  0 = Log errors to database.
 *  1 = Log errors to database and to screen.
541
 */
542
function drupal_error_handler($errno, $message, $filename, $line, $context) {
543 544 545 546 547
  // If the @ error suppression operator was used, error_reporting is temporarily set to 0
  if (error_reporting() == 0) {
    return;
  }

548
  if ($errno & (E_ALL)) {
549
    $types = array(1 => 'error', 2 => 'warning', 4 => 'parse error', 8 => 'notice', 16 => 'core error', 32 => 'core warning', 64 => 'compile error', 128 => 'compile warning', 256 => 'user error', 512 => 'user warning', 1024 => 'user notice', 2048 => 'strict warning');
550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569

    // For database errors, we want the line number/file name of the place that
    // the query was originally called, not _db_query().
    if (isset($context[DB_ERROR])) {
      $backtrace = array_reverse(debug_backtrace());

      // List of functions where SQL queries can originate.
      $query_functions = array('db_query', 'pager_query', 'db_query_range', 'db_query_temporary', 'update_sql');

      // Determine where query function was called, and adjust line/file
      // accordingly.
      foreach ($backtrace as $index => $function) {
        if (in_array($function['function'], $query_functions)) {
          $line = $backtrace[$index]['line'];
          $filename = $backtrace[$index]['file'];
          break;
        }
      }
    }

570
    $entry = $types[$errno] .': '. $message .' in '. $filename .' on line '. $line .'.';
571

572
    // Force display of error messages in update.php
573
    if (variable_get('error_level', 1) == 1 || strstr($_SERVER['SCRIPT_NAME'], 'update.php')) {
574
      drupal_set_message($entry, 'error');
Dries's avatar
Dries committed
575
    }
576

577
    watchdog('php', '%message in %file on line %line.', array('%error' => $types[$errno], '%message' => $message, '%file' => $filename, '%line' => $line), WATCHDOG_ERROR);
Dries's avatar
Dries committed
578 579 580
  }
}

581
function _fix_gpc_magic(&$item) {
Dries's avatar
Dries committed
582
  if (is_array($item)) {
Kjartan's avatar
Kjartan committed
583 584 585
    array_walk($item, '_fix_gpc_magic');
  }
  else {
Kjartan's avatar
Kjartan committed
586
    $item = stripslashes($item);
587 588 589
  }
}

590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607
/**
 * 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);
    }
  }
}

608 609 610 611
/**
 * Correct double-escaping problems caused by "magic quotes" in some PHP
 * installations.
 */
612
function fix_gpc_magic() {
613
  static $fixed = FALSE;
614
  if (!$fixed && ini_get('magic_quotes_gpc')) {
Dries's avatar
Dries committed
615 616 617 618
    array_walk($_GET, '_fix_gpc_magic');
    array_walk($_POST, '_fix_gpc_magic');
    array_walk($_COOKIE, '_fix_gpc_magic');
    array_walk($_REQUEST, '_fix_gpc_magic');
619
    array_walk($_FILES, '_fix_gpc_magic_files');
620
    $fixed = TRUE;
Dries's avatar
Dries committed
621
  }
622 623
}

624
/**
625
 * Translate strings to the page language or a given language.
626
 *
627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646
 * All human-readable text that will be displayed somewhere within a page should be
 * run through the t() function.
 *
 * Examples:
 * @code
 *   if (!$info || !$info['extension']) {
 *     form_set_error('picture_upload', t('The uploaded file was not an image.'));
 *   }
 *
 *   $form['submit'] = array(
 *     '#type' => 'submit',
 *     '#value' => t('Log in'),
 *   );
 * @endcode
 *
 * Any text within t() can be extracted by translators and changed into
 * the equivalent text in their native language.
 *
 * Special variables called "placeholders" are used to signal dynamic
 * information in a string which should not be translated. Placeholders
drumm's avatar
drumm committed
647
 * can also be used for text that may change from time to time
648 649 650 651 652 653 654 655 656 657 658 659 660
 * (such as link paths) to be changed without requiring updates to translations.
 *
 * For example:
 * @code
 *   $output = t('There are currently %members and %visitors online.', array(
 *     '%members' => format_plural($total_users, '1 user', '@count users'),
 *     '%visitors' => format_plural($guests->count, '1 guest', '@count guests')));
 * @endcode
 *
 * There are three styles of placeholders:
 * - !variable, which indicates that the text should be inserted as-is. This is
 *   useful for inserting variables into things like e-mail.
 *   @code
661
 *     $message[] = t("If you don't want to receive such e-mails, you can change your settings at !url.", array('!url' => url("user/$account->uid", array('absolute' => TRUE))));
662 663 664 665 666 667 668 669 670 671 672 673
 *   @endcode
 *
 * - @variable, which indicates that the text should be run through check_plain,
 *   to strip out HTML characters. Use this for any output that's displayed within
 *   a Drupal page.
 *   @code
 *     drupal_set_title($title = t("@name's blog", array('@name' => $account->name)));
 *   @endcode
 *
 * - %variable, which indicates that the string should be highlighted with
 *   theme_placeholder() which shows up by default as <em>emphasized</em>.
 *   @code
674
 *     $message = t('%name-from sent %name-to an e-mail.', array('%name-from' => $user->name, '%name-to' => $account->name));
675 676
 *   @endcode
 *
677
 * When using t(), try to put entire sentences and strings in one t() call.
678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701
 * This makes it easier for translators, as it provides context as to what
 * each word refers to. HTML markup within translation strings is allowed,
 * but should be avoided if possible. The exception is embedded links; link
 * titles add additional context for translators so should be kept in the main
 * string.
 *
 * Here is an example of an incorrect use if t():
 * @code
 *   $output .= t('<p>Go to the @contact-page.</p>', array('@contact-page' => l(t('contact page'), 'contact')));
 * @endcode
 *
 * Here is an example of t() used correctly:
 * @code
 *   $output .= '<p>'. t('Go to the <a href="@contact-page">contact page</a>.', array('@contact-page' => url('contact'))) .'</p>';
 * @endcode
 *
 * Also avoid escaping quotation marks wherever possible.
 *
 * Incorrect:
 * @code
 *   $output .= t('Don\'t click me.');
 * @endcode
 *
 * Correct:
702
 * @code
703
 *   $output .= t("Don't click me.");
704
 * @endcode
705
 *
706
 * @param $string
707
 *   A string containing the English string to translate.
708 709
 * @param $args
 *   An associative array of replacements to make after translation. Incidences
710
 *   of any key in this array are replaced with the corresponding value.
711 712 713 714 715
 *   Based on the first character of the key, the value is escaped and/or themed:
 *    - !variable: inserted as is
 *    - @variable: escape plain text to HTML (check_plain)
 *    - %variable: escape text and theme as a placeholder for user-submitted
 *      content (check_plain + theme_placeholder)
716 717 718
 * @param $langcode
 *   Optional language code to translate to a language other than
 *   what is used to display the page.
719 720
 * @return
 *   The translated string.
721
 */
722
function t($string, $args = array(), $langcode = NULL) {
723
  global $language;
724 725
  static $custom_strings;

726 727
  $langcode = isset($langcode) ? $langcode : $language->language;

728 729 730 731
  // First, check for an array of customized strings. If present, use the array
  // *instead of* database lookups. This is a high performance way to provide a
  // handful of string replacements. See settings.php for examples.
  // Cache the $custom_strings variable to improve performance.
732 733
  if (!isset($custom_strings[$langcode])) {
    $custom_strings[$langcode] = variable_get('locale_custom_strings_'. $langcode, array());
734 735
  }
  // Custom strings work for English too, even if locale module is disabled.
736 737
  if (isset($custom_strings[$langcode][$string])) {
    $string = $custom_strings[$langcode][$string];
738 739
  }
  // Translate with locale module if enabled.
740 741
  elseif (function_exists('locale') && $langcode != 'en') {
    $string = locale($string, $langcode);
742
  }
743
  if (empty($args)) {
744
    return $string;
Kjartan's avatar
Kjartan committed
745 746
  }
  else {
747
    // Transform arguments before inserting them
748
    foreach ($args as $key => $value) {
749 750 751 752 753 754 755 756 757 758 759 760 761 762
      switch ($key[0]) {
        // Escaped only
        case '@':
          $args[$key] = check_plain($value);
        break;
        // Escaped and placeholder
        case '%':
        default:
          $args[$key] = theme('placeholder', $value);
          break;
        // Pass-through
        case '!':
      }
    }
763 764
    return strtr($string, $args);
  }
765 766
}

767
/**
768
 * @defgroup validation Input validation
769
 * @{
770
 * Functions to validate user input.
771 772
 */

773
/**
774 775 776
 * Verify the syntax of the given e-mail address.
 *
 * Empty e-mail addresses are allowed. See RFC 2822 for details.
777
 *
778
 * @param $mail
779
 *   A string containing an e-mail address.
780
 * @return
781
 *   TRUE if the address is in a valid format.
782
 */
783
function valid_email_address($mail) {
784
  $user = '[a-zA-Z0-9_\-\.\+\^!#\$%&*+\/\=\?\`\|\{\}~\']+';
785
  $domain = '(?:(?:[a-zA-Z0-9]|[a-zA-Z0-9][a-zA-Z0-9\-]*[a-zA-Z0-9])\.?)+';
786 787 788
  $ipv4 = '[0-9]{1,3}(\.[0-9]{1,3}){3}';
  $ipv6 = '[0-9a-fA-F]{1,4}(\:[0-9a-fA-F]{1,4}){7}';

Dries's avatar
Dries committed
789
  return preg_match("/^$user@($domain|(\[($ipv4|$ipv6)\]))$/", $mail);
790 791
}

792 793 794
/**
 * Verify the syntax of the given URL.
 *
795 796 797
 * This function should only be used on actual URLs. It should not be used for
 * Drupal menu paths, which can contain arbitrary characters.
 *
798
 * @param $url
799
 *   The URL to verify.
800
 * @param $absolute
801
 *   Whether the URL is absolute (beginning with a scheme such as "http:").
802
 * @return
803
 *   TRUE if the URL is in a valid format.
804
 */
805
function valid_url($url, $absolute = FALSE) {
806
  $allowed_characters = '[a-z0-9\/:_\-_\.\?\$,;~=#&%\+]';
807
  if ($absolute) {
808
    return preg_match("/^(http|https|ftp):\/\/". $allowed_characters ."+$/i", $url);
809 810
  }
  else {
811
    return preg_match("/^". $allowed_characters ."+$/i", $url);
812
  }
813 814
}

815 816 817 818 819 820 821
/**
 * Register an event for the current visitor (hostname/IP) to the flood control mechanism.
 *
 * @param $name
 *   The name of the event.
 */
function flood_register_event($name) {
822
  db_query("INSERT INTO {flood} (event, hostname, timestamp) VALUES ('%s', '%s', %d)", $name, ip_address(), time());
823 824 825 826 827 828 829 830 831 832 833 834
}

/**
 * Check if the current visitor (hostname/IP) is allowed to proceed with the specified event.
 * The user is allowed to proceed if he did not trigger the specified event more than
 * $threshold times per hour.
 *
 * @param $name
 *   The name of the event.
 * @param $number
 *   The maximum number of the specified event per hour (per visitor).
 * @return
835
 *   True if the user did not exceed the hourly threshold. False otherwise.
836 837
 */
function flood_is_allowed($name, $threshold) {
838
  $number = db_result(db_query("SELECT COUNT(*) FROM {flood} WHERE event = '%s' AND hostname = '%s' AND timestamp > %d", $name, ip_address(), time() - 3600));
839 840 841
  return ($number < $threshold ? TRUE : FALSE);
}

842 843
function check_file($filename) {
  return is_uploaded_file($filename);
Dries's avatar
Dries committed
844 845
}

Dries's avatar
Dries committed
846 847 848 849 850
/**
 * Prepare a URL for use in an HTML attribute. Strips harmful protocols.
 *
 */
function check_url($uri) {
851
  return filter_xss_bad_protocol($uri, FALSE);
Dries's avatar
Dries committed
852 853
}

854
/**
855
 * @defgroup format Formatting
856
 * @{
857
 * Functions to format numbers, strings, dates, etc.
858 859
 */

860 861 862 863 864
/**
 * Formats an RSS channel.
 *
 * Arbitrary elements may be added using the $args associative array.
 */
865 866 867
function format_rss_channel($title, $link, $description, $items, $langcode = NULL, $args = array()) {
  global $language;
  $langcode = $langcode ? $langcode : $language->language;
Dries's avatar
Dries committed
868

Dries's avatar
Dries committed
869
  $output = "<channel>\n";
870 871
  $output .= ' <title>'. check_plain($title) ."</title>\n";
  $output .= ' <link>'. check_url($link) ."</link>\n";
872 873 874 875 876

  // 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;).
  $output .= ' <description>'. check_plain(decode_entities(strip_tags($description))) ."</description>\n";
877
  $output .= ' <language>'. check_plain($langcode) ."</language>\n";
878
  $output .= format_xml_elements($args);
Dries's avatar
Dries committed
879 880 881 882 883 884
  $output .= $items;
  $output .= "</channel>\n";

  return $output;
}

885 886 887 888 889
/**
 * Format a single RSS item.
 *
 * Arbitrary elements may be added using the $args associative array.
 */
Dries's avatar
Dries committed
890
function format_rss_item($title, $link, $description, $args = array()) {
Dries's avatar
Dries committed
891
  $output = "<item>\n";
892 893 894
  $output .= ' <title>'. check_plain($title) ."</title>\n";
  $output .= ' <link>'. check_url($link) ."</link>\n";
  $output .= ' <description>'. check_plain($description) ."</description>\n";
895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915
  $output .= format_xml_elements($args);
  $output .= "</item>\n";

  return $output;
}

/**
 * Format XML elements.
 *
 * @param $array
 *   An array where each item represent an element and is either a:
 *   - (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) {
916
  $output = '';
917 918
  foreach ($array as $key => $value) {
    if (is_numeric($key)) {
919 920
      if ($value['key']) {
        $output .= ' <'. $value['key'];
921
        if (isset($value['attributes']) && is_array($value['attributes'])) {
922 923 924
          $output .= drupal_attributes($value['attributes']);
        }

925
        if ($value['value'] != '') {
926
          $output .= '>'. (is_array($value['value']) ? format_xml_elements($value['value']) : check_plain($value['value'])) .'</'. $value['key'] .">\n";
927 928 929 930 931 932 933
        }
        else {
          $output .= " />\n";
        }
      }
    }
    else {
934
      $output .= ' <'. $key .'>'. (is_array($value) ? format_xml_elements($value) : check_plain($value)) ."</$key>\n";
935
    }
Dries's avatar
Dries committed
936
  }
Dries's avatar
Dries committed
937 938 939
  return $output;
}

940
/**
941
 * Format a string containing a count of items.
942
 *
943 944 945
 * This function ensures that the string is pluralized correctly. Since t() is
 * called by this function, make sure not to pass already-localized strings to it.
 *
946 947 948 949 950 951 952 953 954 955 956 957 958
 * 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.',
 *     array('%old-type' => $info->old_type, '%new-type' => $info->new_type)));
 * @endcode
 *
959 960 961 962 963
 * @param $count
 *   The item count to display.
 * @param $singular
 *   The string for the singular case. Please make sure it is clear this is
 *   singular, to ease translation (e.g. use "1 new comment" instead of "1 new").
Dries's avatar
Dries committed
964
 *   Do not use @count in the singular string.
965 966
 * @param $plural
 *   The string for the plural case. Please make sure it is clear this is plural,
967
 *   to ease translation. Use @count in place of the item count, as in "@count
968
 *   new comments".
969 970 971 972 973 974 975 976 977 978
 * @param $args
 *   An associative array of replacements to make after translation. Incidences
 *   of any key in this array are replaced with the corresponding value.
 *   Based on the first character of the key, the value is escaped and/or themed:
 *    - !variable: inserted as is
 *    - @variable: escape plain text to HTML (check_plain)
 *    - %variable: escape text and theme as a placeholder for user-submitted
 *      content (check_plain + theme_placeholder)
 *   Note that you do not need to include @count in this array.
 *   This replacement is done automatically for the plural case.
979 980 981
 * @param $langcode
 *   Optional language code to translate to a language other than
 *   what is used to display the page.
982 983
 * @return
 *   A translated string.
984
 */
985
function format_plural($count, $singular, $plural, $args = array(), $langcode = NULL) {
986
  $args['@count'] = $count;
987
  if ($count == 1) {
988
    return t($singular, $args, $langcode);
989
  }
990 991

  // get the plural index through the gettext formula
992
  $index = (function_exists('locale_get_plural')) ? locale_get_plural($count, $langcode) : -1;
993
  if ($index < 0) { // backward compatibility
994
    return t($plural, $args, $langcode);
995 996 997 998
  }
  else {
    switch ($index) {
      case "0":
999
        return t($singular, $args, $langcode);
1000
      case "1":
1001
        return t($plural, $args, $langcode);
1002
      default:
1003 1004
        unset($args['@count']);
        $args['@count['. $index .']'] = $count;
1005
        return t(strtr($plural, array('@count' => '@count['. $index .']')), $args, $langcode);
1006 1007
    }
  }
Dries's avatar
Dries committed
1008 1009
}

1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030
/**
 * Parse a given byte count.
 *
 * @param $size
 *   The size expressed as a number of bytes with optional SI size and unit
 *   suffix (e.g. 2, 3K, 5MB, 10G).
 * @return
 *   An integer representation of the size.
 */
function parse_size($size) {
  $suffixes = array(
    '' => 1,
    'k' => 1024,
    'm' => 1048576, // 1024 * 1024
    'g' => 1073741824, // 1024 * 1024 * 1024
  );
  if (preg_match('/([0-9]+)\s*(k|m|g)?(b?(ytes?)?)/i', $size, $match)) {
    return $match[1] * $suffixes[drupal_strtolower($match[2])];
  }
}

1031
/**
1032
 * Generate a string representation for the given byte count.
1033
 *
1034 1035
 * @param $size
 *   The size in bytes.
1036 1037 1038
 * @param $langcode
 *   Optional language code to translate to a language other than
 *   what is used to display the page.
1039 1040
 * @return
 *   A translated string representation of the size.
1041
 */
1042
function format_size($size, $langcode = NULL) {
1043
  if ($size < 1024) {
1044
    return format_plural($size, '1 byte', '@count bytes', array(), $langcode);
Dries's avatar
Dries committed
1045
  }
1046
  else {
Dries's avatar
Dries committed
1047
    $size = round($size / 1024, 2);
1048
    $suffix = t('KB', array(), $langcode);
1049 1050
    if ($size >= 1024) {
      $size = round($size / 1024, 2);
1051
      $suffix = t('MB', array(), $langcode);
1052
    }
1053
    return t('@size @suffix', array('@size' => $size, '@suffix' => $suffix), $langcode);
Dries's avatar
Dries committed
1054 1055 1056
  }
}

1057
/**
1058
 * Format a time interval with the requested granularity.
1059
 *
1060 1061 1062 1063
 * @param $timestamp
 *   The length of the interval in seconds.
 * @param $granularity
 *   How many different units to display in the string.
1064 1065 1066
 * @param $langcode
 *   Optional language code to translate to a language other than
 *   what is used to display the page.
1067 1068
 * @return
 *   A translated string representation of the interval.
1069
 */
1070
function format_interval($timestamp, $granularity = 2, $langcode = NULL) {
1071
  $units = array('1 year|@count years' => 31536000, '1 week|@count weeks' => 604800, '1 day|@count days' => 86400, '1 hour|@count hours' => 3600, '1 min|@count min' => 60, '1 sec|@count sec' => 1);
1072
  $output = '';
1073
  foreach ($units as $key => $value) {
1074
    $key = explode('|', $key);
Dries's avatar
Dries committed
1075
    if ($timestamp >= $value) {
1076
      $output .= ($output ? ' ' : '') . format_plural(floor($timestamp / $value), $key[0], $key[1], array(), $langcode);
Dries's avatar
Dries committed
1077
      $timestamp %= $value;
1078 1079 1080 1081 1082
      $granularity--;
    }

    if ($granularity == 0) {
      break;
Dries's avatar
Dries committed
1083 1084
    }
  }
1085
  return $output ? $output : t('0 sec', array(), $langcode);
Dries's avatar
Dries committed
1086 1087
}

1088
/**
1089 1090
 * Format a date with the given configured format or a custom format string.
 *
1091 1092 1093 1094
 * Drupal allows administrators to select formatting strings for 'small',
 * 'medium' and 'large' date formats. This function can handle these formats,
 * as well as any custom format.
 *
1095 1096 1097 1098 1099 1100
 * @param $timestamp
 *   The exact date to format, as a UNIX timestamp.
 * @param $type
 *   The format to use. Can be "small", "medium" or "large" for the preconfigured
 *   date formats. If "custom" is specified, then $format is required as well.
 * @param $format
1101 1102 1103
 *   A PHP date format string as required by date(). A backslash should be used
 *   before a character to avoid interpreting the character as part of a date
 *   format.
1104 1105
 * @param $timezone
 *   Time zone offset in seconds; if omitted, the user's time zone is used.
1106 1107 1108
 * @param $langcode
 *   Optional language code to translate to a language other than
 *   what is used to display the page.
1109 1110
 * @return
 *   A translated date string in the requested format.
1111
 */
1112
function format_date($timestamp, $type = 'medium', $format = '', $timezone = NULL, $langcode = NULL) {
Dries's avatar