common.inc 125 KB
Newer Older
Dries's avatar
 
Dries committed
1
<?php
2
// $Id$
Dries's avatar
 
Dries committed
3

Dries's avatar
 
Dries committed
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
/**
 * Set content for a specified region.
 *
 * @param $region
 *   Page region the content is assigned to.
 * @param $data
 *   Content to be set.
 */
35
function drupal_set_content($region = NULL, $data = NULL) {
36 37 38 39 40 41 42 43 44 45 46 47
  static $content = array();

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

/**
 * Get assigned content.
 *
 * @param $region
48 49
 *   A specified region to fetch content for. If NULL, all regions will be
 *   returned.
50 51 52
 * @param $delimiter
 *   Content to be inserted between exploded array elements.
 */
53
function drupal_get_content($region = NULL, $delimiter = ' ') {
54
  $content = drupal_set_content();
55 56
  if (isset($region)) {
    if (isset($content[$region]) && is_array($content[$region])) {
Steven Wittens's avatar
Steven Wittens committed
57
      return implode($delimiter, $content[$region]);
58
    }
59 60 61 62
  }
  else {
    foreach (array_keys($content) as $region) {
      if (is_array($content[$region])) {
Steven Wittens's avatar
Steven Wittens committed
63
        $content[$region] = implode($delimiter, $content[$region]);
64 65 66 67 68 69
      }
    }
    return $content;
  }
}

Dries's avatar
 
Dries committed
70
/**
Dries's avatar
 
Dries committed
71
 * Set the breadcrumb trail for the current page.
Dries's avatar
 
Dries committed
72
 *
Dries's avatar
 
Dries committed
73 74 75
 * @param $breadcrumb
 *   Array of links, starting with "home" and proceeding up to but not including
 *   the current page.
Kjartan's avatar
Kjartan committed
76
 */
Dries's avatar
 
Dries committed
77 78 79
function drupal_set_breadcrumb($breadcrumb = NULL) {
  static $stored_breadcrumb;

80
  if (!is_null($breadcrumb)) {
Dries's avatar
 
Dries committed
81 82 83 84 85
    $stored_breadcrumb = $breadcrumb;
  }
  return $stored_breadcrumb;
}

Dries's avatar
 
Dries committed
86 87 88
/**
 * Get the breadcrumb trail for the current page.
 */
Dries's avatar
 
Dries committed
89 90 91
function drupal_get_breadcrumb() {
  $breadcrumb = drupal_set_breadcrumb();

92
  if (is_null($breadcrumb)) {
Dries's avatar
 
Dries committed
93 94 95 96 97 98
    $breadcrumb = menu_get_active_breadcrumb();
  }

  return $breadcrumb;
}

Dries's avatar
Dries committed
99
/**
Dries's avatar
 
Dries committed
100
 * Add output to the head tag of the HTML page.
101
 *
Dries's avatar
 
Dries committed
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) {
Dries's avatar
 
Dries committed
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;
}

Dries's avatar
 
Dries committed
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() {
Dries's avatar
 
Dries committed
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();
}

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

Dries's avatar
Dries committed
128
/**
Dries's avatar
 
Dries committed
129
 * Set an HTTP response header for the current page.
130
 *
131
 * Note: When sending a Content-Type header, always include a 'charset' type,
132
 * 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.
Dries's avatar
 
Dries committed
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
}

Dries's avatar
 
Dries committed
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
 * Add a feed URL for the current page.
 *
157 158
 * This function can be called as long the HTML header hasn't been sent.
 *
159
 * @param $url
160
 *   A url for the feed.
161
 * @param $title
162
 *   The title of the feed.
163
 */
164
function drupal_add_feed($url = NULL, $title = '') {
165 166
  static $stored_feed_links = array();

167
  if (!is_null($url) && !isset($stored_feed_links[$url])) {
168
    $stored_feed_links[$url] = theme('feed_icon', $url, $title);
169 170 171 172 173

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

/**
 * Get the feed URLs for the current page.
 *
 * @param $delimiter
182
 *   A delimiter to split feeds by.
183 184 185 186 187 188
 */
function drupal_get_feeds($delimiter = "\n") {
  $feeds = drupal_add_feed();
  return implode($feeds, $delimiter);
}

Dries's avatar
 
Dries committed
189 190 191
/**
 * @name HTTP handling
 * @{
Dries's avatar
 
Dries committed
192
 * Functions to properly handle HTTP responses.
Dries's avatar
 
Dries committed
193 194
 */

195 196 197 198
/**
 * Parse an array into a valid urlencoded query string.
 *
 * @param $query
199
 *   The array to be processed e.g. $_GET.
200
 * @param $exclude
201 202
 *   The array filled with keys to be excluded. Use parent[child] to exclude
 *   nested items.
203
 * @param $parent
204
 *   Should not be passed, only used in recursive calls.
205
 * @return
206
 *   An urlencoded string which can be appended to/as the URL query string.
207 208 209 210 211
 */
function drupal_query_string_encode($query, $exclude = array(), $parent = '') {
  $params = array();

  foreach ($query as $key => $value) {
212
    $key = drupal_urlencode($key);
213
    if ($parent) {
214
      $key = $parent . '[' . $key . ']';
215 216
    }

217
    if (in_array($key, $exclude)) {
218 219 220 221 222 223 224
      continue;
    }

    if (is_array($value)) {
      $params[] = drupal_query_string_encode($value, $exclude, $key);
    }
    else {
225
      $params[] = $key . '=' . drupal_urlencode($value);
226 227 228 229 230 231
    }
  }

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

232
/**
233
 * Prepare a destination query string for use in combination with drupal_goto().
234
 *
235 236 237 238
 * 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.
239 240 241 242
 *
 * @see drupal_goto()
 */
function drupal_get_destination() {
243
  if (isset($_REQUEST['destination'])) {
244
    return 'destination=' . urlencode($_REQUEST['destination']);
245 246
  }
  else {
247 248
    // Use $_GET here to retrieve the original path in source form.
    $path = isset($_GET['q']) ? $_GET['q'] : '';
249 250
    $query = drupal_query_string_encode($_GET, array('q'));
    if ($query != '') {
251
      $path .= '?' . $query;
252
    }
253
    return 'destination=' . urlencode($path);
254 255 256
  }
}

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

299
  if (isset($_REQUEST['destination'])) {
300
    extract(parse_url(urldecode($_REQUEST['destination'])));
301 302
  }

303
  $url = url($path, array('query' => $query, 'fragment' => $fragment, 'absolute' => TRUE));
304 305
  // Remove newlines from the URL to avoid header injection attacks.
  $url = str_replace(array("\n", "\r"), '', $url);
Kjartan's avatar
Kjartan committed
306

307
  // Allow modules to react to the end of the page request before redirecting.
308
  // We do not want this while running update.php.
309
  if (!defined('MAINTENANCE_MODE') || MAINTENANCE_MODE != 'update') {
310 311
    module_invoke_all('exit', $url);
  }
Dries's avatar
 
Dries committed
312

313
  // Even though session_write_close() is registered as a shutdown function, we
314
  // need all session data written to the database before redirecting.
315
  session_write_close();
316

317
  header('Location: ' . $url, TRUE, $http_response_code);
318 319

  // The "Location" header sends a redirect status code to the HTTP daemon. In
320 321
  // some cases this can be wrong, so we make sure none of the code below the
  // drupal_goto() call gets executed upon redirection.
Kjartan's avatar
Kjartan committed
322 323 324
  exit();
}

325
/**
326
 * Generates a site offline message.
327 328
 */
function drupal_site_offline() {
329
  drupal_maintenance_theme();
330
  drupal_set_header($_SERVER['SERVER_PROTOCOL'] . ' 503 Service unavailable');
331
  drupal_set_title(t('Site offline'));
332
  print theme('maintenance_page', filter_xss_admin(variable_get('site_offline_message',
333
    t('@site is currently under maintenance. We should be back shortly. Thank you for your patience.', array('@site' => variable_get('site_name', 'Drupal'))))));
334 335
}

Kjartan's avatar
Kjartan committed
336 337 338
/**
 * Generates a 404 error if the request can not be handled.
 */
Dries's avatar
 
Dries committed
339
function drupal_not_found() {
340
  drupal_set_header($_SERVER['SERVER_PROTOCOL'] . ' 404 Not Found');
341

342
  watchdog('page not found', check_plain($_GET['q']), NULL, WATCHDOG_WARNING);
343

344
  // Keep old path for reference.
345 346 347 348
  if (!isset($_REQUEST['destination'])) {
    $_REQUEST['destination'] = $_GET['q'];
  }

Dries's avatar
 
Dries committed
349
  $path = drupal_get_normal_path(variable_get('site_404', ''));
drumm's avatar
drumm committed
350
  if ($path && $path != $_GET['q']) {
351 352 353
    // Set the active item in case there are tabs to display, or other
    // dependencies on the path.
    menu_set_active_item($path);
354
    $return = menu_execute_active_handler($path);
355
  }
Dries's avatar
 
Dries committed
356

357
  if (empty($return) || $return == MENU_NOT_FOUND || $return == MENU_ACCESS_DENIED) {
drumm's avatar
drumm committed
358
    drupal_set_title(t('Page not found'));
359
    $return = t('The requested page could not be found.');
Dries's avatar
 
Dries committed
360
  }
361

362
  // To conserve CPU and bandwidth, omit the blocks.
363
  print theme('page', $return, FALSE);
Dries's avatar
 
Dries committed
364
}
Dries's avatar
 
Dries committed
365

Dries's avatar
 
Dries committed
366 367 368 369
/**
 * Generates a 403 error if the request is not allowed.
 */
function drupal_access_denied() {
370
  drupal_set_header($_SERVER['SERVER_PROTOCOL'] . ' 403 Forbidden');
371
  watchdog('access denied', check_plain($_GET['q']), NULL, WATCHDOG_WARNING);
Dries's avatar
 
Dries committed
372

373
  // Keep old path for reference.
374 375 376 377
  if (!isset($_REQUEST['destination'])) {
    $_REQUEST['destination'] = $_GET['q'];
  }

Dries's avatar
 
Dries committed
378
  $path = drupal_get_normal_path(variable_get('site_403', ''));
drumm's avatar
drumm committed
379
  if ($path && $path != $_GET['q']) {
380
    // Set the active item in case there are tabs to display or other
381 382
    // dependencies on the path.
    menu_set_active_item($path);
383
    $return = menu_execute_active_handler($path);
384
  }
Dries's avatar
 
Dries committed
385

386
  if (empty($return) || $return == MENU_NOT_FOUND || $return == MENU_ACCESS_DENIED) {
drumm's avatar
drumm committed
387 388
    drupal_set_title(t('Access denied'));
    $return = t('You are not authorized to access this page.');
Dries's avatar
 
Dries committed
389
  }
390
  print theme('page', $return);
Dries's avatar
 
Dries committed
391 392
}

Dries's avatar
 
Dries committed
393
/**
Dries's avatar
 
Dries committed
394
 * Perform an HTTP request.
Dries's avatar
 
Dries committed
395
 *
Dries's avatar
 
Dries committed
396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411
 * 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,
412
 *   data and redirect status.
Dries's avatar
 
Dries committed
413 414
 */
function drupal_http_request($url, $headers = array(), $method = 'GET', $data = NULL, $retry = 3) {
415
  global $db_prefix;
416
  static $self_test = FALSE;
417
  $result = new stdClass();
418 419 420 421 422 423 424 425 426 427 428 429 430 431 432
  // Try to clear the drupal_http_request_fails variable if it's set. We
  // can't tie this call to any error because there is no surefire way to
  // tell whether a request has failed, so we add the check to places where
  // some parsing has failed.
  if (!$self_test && variable_get('drupal_http_request_fails', FALSE)) {
    $self_test = TRUE;
    $works = module_invoke('system', 'check_http_request');
    $self_test = FALSE;
    if (!$works) {
      // Do not bother with further operations if we already know that we
      // have no chance.
      $result->error = t("The server can't issue HTTP requests");
      return $result;
    }
  }
Dries's avatar
 
Dries committed
433

434
  // Parse the URL and make sure we can handle the schema.
435
  $uri = @parse_url($url);
436

437 438
  if ($uri == FALSE) {
    $result->error = 'unable to parse URL';
439 440 441
    return $result;
  }

442 443
  if (!isset($uri['scheme'])) {
    $result->error = 'missing schema';
444 445 446
    return $result;
  }

Dries's avatar
 
Dries committed
447 448
  switch ($uri['scheme']) {
    case 'http':
Dries's avatar
Dries committed
449
      $port = isset($uri['port']) ? $uri['port'] : 80;
450
      $host = $uri['host'] . ($port != 80 ? ':' . $port : '');
451
      $fp = @fsockopen($uri['host'], $port, $errno, $errstr, 15);
Dries's avatar
 
Dries committed
452 453
      break;
    case 'https':
Dries's avatar
 
Dries committed
454
      // Note: Only works for PHP 4.3 compiled with OpenSSL.
Dries's avatar
Dries committed
455
      $port = isset($uri['port']) ? $uri['port'] : 443;
456 457
      $host = $uri['host'] . ($port != 443 ? ':' . $port : '');
      $fp = @fsockopen('ssl://' . $uri['host'], $port, $errno, $errstr, 20);
Dries's avatar
 
Dries committed
458 459
      break;
    default:
460
      $result->error = 'invalid schema ' . $uri['scheme'];
Dries's avatar
 
Dries committed
461 462 463
      return $result;
  }

Dries's avatar
 
Dries committed
464
  // Make sure the socket opened properly.
Dries's avatar
 
Dries committed
465
  if (!$fp) {
466 467
    // When a network error occurs, we use a negative number so it does not
    // clash with the HTTP status codes.
468 469
    $result->code = -$errno;
    $result->error = trim($errstr);
Dries's avatar
 
Dries committed
470 471 472
    return $result;
  }

Dries's avatar
 
Dries committed
473
  // Construct the path to act on.
Dries's avatar
Dries committed
474 475
  $path = isset($uri['path']) ? $uri['path'] : '/';
  if (isset($uri['query'])) {
476
    $path .= '?' . $uri['query'];
Dries's avatar
 
Dries committed
477 478
  }

Dries's avatar
 
Dries committed
479
  // Create HTTP request.
Dries's avatar
 
Dries committed
480
  $defaults = array(
481
    // RFC 2616: "non-standard ports MUST, default ports MAY be included".
482 483
    // We don't add the port to prevent from breaking rewrite rules checking the
    // host that do not take into account the port number.
484
    'Host' => "Host: $host",
485
    'User-Agent' => 'User-Agent: Drupal (+http://drupal.org/)',
486
    'Content-Length' => 'Content-Length: ' . strlen($data)
Dries's avatar
 
Dries committed
487 488
  );

489 490
  // If the server url has a user then attempt to use basic authentication
  if (isset($uri['user'])) {
491
    $defaults['Authorization'] = 'Authorization: Basic ' . base64_encode($uri['user'] . (!empty($uri['pass']) ? ":" . $uri['pass'] : ''));
492 493
  }

494 495 496 497 498 499 500 501 502 503
  // 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.
  if (preg_match("/^simpletest\d+/", $db_prefix)) {
    $headers['User-Agent'] = $db_prefix;
  }

Dries's avatar
 
Dries committed
504
  foreach ($headers as $header => $value) {
505
    $defaults[$header] = $header . ': ' . $value;
Dries's avatar
 
Dries committed
506 507
  }

508
  $request = $method . ' ' . $path . " HTTP/1.0\r\n";
Dries's avatar
 
Dries committed
509 510 511
  $request .= implode("\r\n", $defaults);
  $request .= "\r\n\r\n";
  if ($data) {
512
    $request .= $data . "\r\n";
Dries's avatar
 
Dries committed
513 514 515 516 517 518
  }
  $result->request = $request;

  fwrite($fp, $request);

  // Fetch response.
519
  $response = '';
520 521
  while (!feof($fp) && $chunk = fread($fp, 1024)) {
    $response .= $chunk;
Dries's avatar
 
Dries committed
522 523 524 525
  }
  fclose($fp);

  // Parse response.
526 527
  list($split, $result->data) = explode("\r\n\r\n", $response, 2);
  $split = preg_split("/\r\n|\n|\r/", $split);
528

529
  list($protocol, $code, $text) = explode(' ', trim(array_shift($split)), 3);
Dries's avatar
 
Dries committed
530 531 532
  $result->headers = array();

  // Parse headers.
533
  while ($line = trim(array_shift($split))) {
Dries's avatar
 
Dries committed
534
    list($header, $value) = explode(':', $line, 2);
535 536 537
    if (isset($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.
538
      $result->headers[$header] .= ',' . trim($value);
539 540 541 542
    }
    else {
      $result->headers[$header] = trim($value);
    }
Dries's avatar
 
Dries committed
543 544 545 546 547 548 549 550 551
  }

  $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'
  );
552 553
  // 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
554 555 556 557 558 559 560 561 562 563 564 565 566 567
  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) {
568 569
        $result = drupal_http_request($location, $headers, $method, $data, --$retry);
        $result->redirect_code = $code;
Dries's avatar
 
Dries committed
570 571 572 573 574 575 576 577 578 579 580
      }
      $result->redirect_url = $location;

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

  $result->code = $code;
  return $result;
}
Dries's avatar
 
Dries committed
581 582 583
/**
 * @} End of "HTTP handling".
 */
Dries's avatar
 
Dries committed
584

Dries's avatar
 
Dries committed
585
/**
586
 * Custom PHP error handler.
587
 *
588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631
 * @param $error_level
 *   The level of the error raised.
 * @param $message
 *   The error message.
 * @param $filename
 *   The filename that the error was raised in.
 * @param $line
 *   The line number the error was raised at.
 * @param $context
 *   An array that points to the active symbol table at the point the error occurred.
 */
function _drupal_error_handler($error_level, $message, $filename, $line, $context) {
  if ($error_level & error_reporting()) {
    // All these constants are documented at http://php.net/manual/en/errorfunc.constants.php
    $types = array(
      E_ERROR => 'Error',
      E_WARNING => 'Warning',
      E_PARSE => 'Parse error',
      E_NOTICE => 'Notice',
      E_CORE_ERROR => 'Core error',
      E_CORE_WARNING => 'Core warning',
      E_COMPILE_ERROR => 'Compile error',
      E_COMPILE_WARNING => 'Compile warning',
      E_USER_ERROR => 'User error',
      E_USER_WARNING => 'User warning',
      E_USER_NOTICE => 'User notice',
      E_STRICT => 'Strict warning',
      E_RECOVERABLE_ERROR => 'Recoverable fatal error'
    );
    $backtrace = debug_backtrace();
    // We treat recoverable errors as fatal.
    _drupal_log_error(isset($types[$error_level]) ? $types[$error_level] : 'Unknown error', $message, $backtrace, $error_level == E_RECOVERABLE_ERROR);
  }
}

/**
 * Custom PHP exception handler.
 *
 * Uncaught exceptions are those not enclosed in a try/catch block. They are
 * always fatal: the execution of the script will stop as soon as the exception
 * handler exits.
 *
 * @param $exception
 *   The exception object that was thrown.
Dries's avatar
 
Dries committed
632
 */
633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650
function _drupal_exception_handler($exception) {
  $backtrace = $exception->getTrace();
  // Add the line throwing the exception to the backtrace.
  array_unshift($backtrace, array('line' => $exception->getLine(), 'file' => $exception->getFile()));

  // For PDOException errors, we try to return the initial caller,
  // skipping internal functions of the database layer.
  if ($exception instanceof PDOException) {
    // The first element in the stack is the call, the second element gives us the caller.
    // We skip calls that occurred in one of the classes of the database layer
    // or in one of its global functions.
    $db_functions = array('db_query', 'pager_query', 'db_query_range', 'db_query_temporary', 'update_sql');
    while (($caller = $backtrace[1]) &&
         ((isset($caller['class']) && (strpos($caller['class'], 'Query') !== FALSE || strpos($caller['class'], 'Database') !== FALSE)) ||
         in_array($caller['function'], $db_functions))) {
      // We remove that call.
      array_shift($backtrace);
    }
651 652
  }

653 654 655
  // Log the message to the watchdog and return an error page to the user.
  _drupal_log_error(get_class($exception), $exception->getMessage(), $backtrace, TRUE);
}
656

657 658 659 660 661 662 663 664 665 666 667 668 669 670
/**
 * Log a PHP error or exception, display an error page in fatal cases.
 *
 * @param $type
 *   The type of the error (Error, Warning, ...).
 * @param $message
 *   The message associated to the error.
 * @param $backtrace
 *   The backtrace of function calls that led to this error.
 * @param $fatal
 *   TRUE if the error is fatal.
 */
function _drupal_log_error($type, $message, $backtrace, $fatal) {
  $caller = _drupal_get_last_caller($backtrace);
671

672 673 674 675 676 677 678
  // Initialize a maintenance theme early if the boostrap was not complete.
  // Do it early because drupal_set_message() triggers an init_theme().
  if ($fatal && (drupal_get_bootstrap_phase() != DRUPAL_BOOTSTRAP_FULL)) {
    unset($GLOBALS['theme']);
    define('MAINTENANCE_MODE', 'error');
    drupal_maintenance_theme();
  }
679

680 681 682 683
  // Force display of error messages in update.php.
  if (variable_get('error_level', 1) == 1 || (defined('MAINTENANCE_MODE') && MAINTENANCE_MODE == 'update')) {
    drupal_set_message(t('@type: %message in %function (line %line of %file).', array('@type' => $type, '%message' => $message, '%function' => $caller['function'], '%line' => $caller['line'], '%file' => $caller['file'])), 'error');
  }
684

685
  watchdog('php', '%type: %message in %function (line %line of %file).', array('%type' => $type, '%message' => $message, '%function' => $caller['function'], '%file' => $caller['file'], '%line' => $caller['line']), WATCHDOG_ERROR);
Dries's avatar
 
Dries committed
686

687 688 689 690 691
  if ($fatal) {
    drupal_set_header($_SERVER['SERVER_PROTOCOL'] . ' Service unavailable');
    drupal_set_title(t('Error'));
    if (drupal_get_bootstrap_phase() == DRUPAL_BOOTSTRAP_FULL) {
      print theme('page', t('The website encountered an unexpected error. Please try again later.'), FALSE);
Dries's avatar
Dries committed
692
    }
693
    else {
694
      print theme('maintenance_page', t('The website encountered an unexpected error. Please try again later.'), FALSE);
695 696
    }
    exit;
Dries's avatar
 
Dries committed
697 698 699
  }
}

700
/**
701
 * Gets the last caller from a backtrace.
702 703 704 705 706 707 708
 *
 * @param $backtrace
 *   A standard PHP backtrace.
 * @return
 *   An associative array with keys 'file', 'line' and 'function'.
 */
function _drupal_get_last_caller($backtrace) {
709 710 711 712 713 714
  // Errors that occur inside PHP internal functions
  // do not generate information about file and line.
  while ($backtrace && !isset($backtrace[0]['line'])) {
    array_shift($backtrace);
  }

715 716 717
  // The first trace is the call itself.
  // It gives us the line and the file of the last call.
  $call = $backtrace[0];
718

719 720 721 722 723 724 725 726 727 728 729 730 731 732 733
  // The second call give us the function where the call originated.
  if (isset($backtrace[1])) {
    if (isset($backtrace[1]['class'])) {
      $call['function'] = $backtrace[1]['class'] . $backtrace[1]['type'] . $backtrace[1]['function'] . '()';
    }
    else {
      $call['function'] = $backtrace[1]['function'] . '()';
    }
  }
  else {
    $call['function'] = 'main()';
  }
  return $call;
}

Dries's avatar
 
Dries committed
734
function _fix_gpc_magic(&$item) {
Dries's avatar
Dries committed
735
  if (is_array($item)) {
Kjartan's avatar
Kjartan committed
736 737 738
    array_walk($item, '_fix_gpc_magic');
  }
  else {
Kjartan's avatar
Kjartan committed
739
    $item = stripslashes($item);
Dries's avatar
 
Dries committed
740 741 742
  }
}

743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760
/**
 * 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
761
/**
762
 * Fix double-escaping problems caused by "magic quotes" in some PHP installations.
Dries's avatar
 
Dries committed
763
 */
Dries's avatar
 
Dries committed
764
function fix_gpc_magic() {
765
  static $fixed = FALSE;
Dries's avatar
 
Dries committed
766
  if (!$fixed && ini_get('magic_quotes_gpc')) {
Dries's avatar
Dries committed
767 768 769 770
    array_walk($_GET, '_fix_gpc_magic');
    array_walk($_POST, '_fix_gpc_magic');
    array_walk($_COOKIE, '_fix_gpc_magic');
    array_walk($_REQUEST, '_fix_gpc_magic');
771
    array_walk($_FILES, '_fix_gpc_magic_files');
772
    $fixed = TRUE;
Dries's avatar
Dries committed
773
  }
Dries's avatar
 
Dries committed
774 775
}

Kjartan's avatar
Kjartan committed
776
/**
777
 * Translate strings to the page language or a given language.
Kjartan's avatar
Kjartan committed
778
 *
779 780
 * All human-readable text that will be displayed somewhere within a page should
 * be run through the t() function.
781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798
 *
 * 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
799
 * can also be used for text that may change from time to time
800 801 802 803 804 805 806 807 808 809 810 811 812
 * (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
813
 *     $message[] = t("If you don't want to receive such e-mails, you can change your settings at !url.", array('!url' => url("user/$account->uid", array('absolute' => TRUE))));
814 815 816
 *   @endcode
 *
 * - @variable, which indicates that the text should be run through check_plain,
817
 *   to escape HTML characters. Use this for any output that's displayed within
818 819
 *   a Drupal page.
 *   @code
820
 *     drupal_set_title($title = t("@name's blog", array('@name' => $account->name)), PASS_THROUGH);
821 822
 *   @endcode
 *
823 824 825
 * - %variable, which indicates that the string should be HTML escaped and
 *   highlighted with theme_placeholder() which shows up by default as
 *   <em>emphasized</em>.
826
 *   @code
827
 *     $message = t('%name-from sent %name-to an e-mail.', array('%name-from' => $user->name, '%name-to' => $account->name));
828 829
 *   @endcode
 *
830
 * When using t(), try to put entire sentences and strings in one t() call.
831 832 833 834
 * 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 are embedded links; link titles add a
 * context for translators, so should be kept in the main string.
835
 *
836
 * Here is an example of incorrect usage of t():
837 838 839 840 841 842
 * @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
843
 *   $output .= '<p>' . t('Go to the <a href="@contact-page">contact page</a>.', array('@contact-page' => url('contact'))) . '</p>';
844 845 846 847 848 849 850 851 852 853
 * @endcode
 *
 * Also avoid escaping quotation marks wherever possible.
 *
 * Incorrect:
 * @code
 *   $output .= t('Don\'t click me.');
 * @endcode
 *
 * Correct:
Dries's avatar
 
Dries committed
854
 * @code
855
 *   $output .= t("Don't click me.");
Dries's avatar
 
Dries committed
856
 * @endcode
Kjartan's avatar
Kjartan committed
857
 *
Dries's avatar
 
Dries committed
858
 * @param $string
Dries's avatar
 
Dries committed
859
 *   A string containing the English string to translate.
Dries's avatar
 
Dries committed
860 861
 * @param $args
 *   An associative array of replacements to make after translation. Incidences
Dries's avatar
 
Dries committed
862
 *   of any key in this array are replaced with the corresponding value.
863 864 865 866 867
 *   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)
868
 * @param $langcode
869 870
 *   Optional language code to translate to a language other than what is used
 *   to display the page.
Dries's avatar
 
Dries committed
871 872
 * @return
 *   The translated string.
Kjartan's avatar
Kjartan committed
873
 */
874
function t($string, $args = array(), $langcode = NULL) {
875
  global $language;
876 877
  static $custom_strings;

878 879 880
  if (!isset($langcode)) {
    $langcode = $language->language;
  }
881

882 883 884 885
  // 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 $custom_strings variable to improve performance.
886
  if (!isset($custom_strings[$langcode])) {
887
    $custom_strings[$langcode] = variable_get('locale_custom_strings_' . $langcode, array());
888 889
  }
  // Custom strings work for English too, even if locale module is disabled.
890 891
  if (isset($custom_strings[$langcode][$string])) {
    $string = $custom_strings[$langcode][$string];
892 893
  }
  // Translate with locale module if enabled.
894 895
  elseif (function_exists('locale') && $langcode != 'en') {
    $string = locale($string, $langcode);
Dries's avatar
 
Dries committed
896
  }
897
  if (empty($args)) {
Dries's avatar
 
Dries committed
898
    return $string;
Kjartan's avatar
Kjartan committed
899 900
  }
  else {
901
    // Transform arguments before inserting them.
902
    foreach ($args as $key => $value) {
903 904
      switch ($key[0]) {
        case '@':
905
          // Escaped only.
906
          $args[$key] = check_plain($value);
907
          break;
908

909 910
        case '%':
        default:
911
          // Escaped and placeholder.
912 913
          $args[$key] = theme('placeholder', $value);
          break;
914

915
        case '!':
916
          // Pass-through.
917 918
      }
    }
Dries's avatar
 
Dries committed
919 920
    return strtr($string, $args);
  }
Dries's avatar
 
Dries committed
921 922
}

Kjartan's avatar
Kjartan committed
923
/**
Dries's avatar
 
Dries committed
924
 * @defgroup validation Input validation
Dries's avatar
 
Dries committed
925
 * @{
Dries's avatar
 
Dries committed
926
 * Functions to validate user input.
Kjartan's avatar
Kjartan committed
927 928
 */

929
/**
Dries's avatar
 
Dries committed
930 931 932
 * Verify the syntax of the given e-mail address.
 *
 * Empty e-mail addresses are allowed. See RFC 2822 for details.
933
 *
Dries's avatar
 
Dries committed
934
 * @param $mail
935
 *   A string containing an e-mail address.
Dries's avatar
 
Dries committed
936
 * @return
Dries's avatar
 
Dries committed
937
 *   TRUE if the address is in a valid format.
938
 */
Dries's avatar
 
Dries committed
939
function valid_email_address($mail) {
940
  return (bool)filter_var($mail, FILTER_VALIDATE_EMAIL);
941 942
}

Dries's avatar
 
Dries committed
943 944 945
/**
 * Verify the syntax of the given URL.
 *
946 947 948
 * This function should only be used on actual URLs. It should not be used for
 * Drupal menu paths, which can contain arbitrary characters.
 *
Dries's avatar
 
Dries committed
949
 * @param $url
Dries's avatar
 
Dries committed
950
 *   The URL to verify.
Dries's avatar
 
Dries committed
951
 * @param $absolute
Dries's avatar
 
Dries committed
952
 *   Whether the URL is absolute (beginning with a scheme such as "http:").
Dries's avatar
 
Dries committed
953
 * @return
Dries's avatar
 
Dries committed
954
 *   TRUE if the URL is in a valid format.
Dries's avatar
 
Dries committed
955
 */
Dries's avatar
 
Dries committed
956
function valid_url($url, $absolute = FALSE) {
957
  $allowed_characters = '[a-z0-9\/:_\-_\.\?\$,;~=#&%\+]';
958
  if ($absolute) {
959
    return (bool)preg_match("/^(http|https|ftp):\/\/" . $allowed_characters . "+$/i", $url);
960 961
  }
  else {
962
    return (bool)preg_match("/^" . $allowed_characters . "+$/i", $url);
963
  }
Dries's avatar
 
Dries committed
964 965
}

966 967 968 969
/**
 * @} End of "defgroup validation".
 */

Dries's avatar
 
Dries committed
970 971 972 973
/**
 * Register an event for the current visitor (hostname/IP) to the flood control mechanism.
 *
 * @param $name
974
 *   The name of an event.
Dries's avatar
 
Dries committed
975 976
 */
function flood_register_event($name) {
977 978 979 980 981 982 983
  db_insert('flood')
    ->fields(array(
      'event' => $name,
      'hostname' => ip_address(),
      'timestamp' => REQUEST_TIME,
    ))
    ->execute();
Dries's avatar
 
Dries committed
984 985 986 987
}

/**
 * Check if the current visitor (hostname/IP) is allowed to proceed with the specified event.
988 989 990
 *
 * The user is allowed to proceed if he did not trigger the specified event more
 * than $threshold times per hour.
Dries's avatar
 
Dries committed
991 992 993 994 995 996
 *
 * @param $name
 *   The name of the event.
 * @param $number
 *   The maximum number of the specified event per hour (per visitor).
 * @return
997
 *   True if the user did not exceed the hourly threshold. False otherwise.
Dries's avatar
 
Dries committed
998 999
 */
function flood_is_allowed($name, $threshold) {
1000 1001 1002 1003 1004 1005
  $number = db_query("SELECT COUNT(*) FROM {flood} WHERE event = :event AND hostname = :hostname AND timestamp > :timestamp", array(
    ':event' => $name,
    ':hostname' => ip_address(),
    ':timestamp' => REQUEST_TIME - 3600))
    ->fetchField();
  return ($number < $threshold);
Dries's avatar
 
Dries committed
1006 1007
}

1008 1009
function check_file($filename) {
  return is_uploaded_file($filename);
Dries's avatar
 
Dries committed
1010 1011
}

Dries's avatar
Dries committed
1012 1013 1014 1015
/**
 * Prepare a URL for use in an HTML attribute. Strips harmful protocols.
 */
function check_url($uri) {
1016
  return filter_xss_bad_protocol($uri, FALSE);
Dries's avatar
Dries committed
1017 1018
}

Dries's avatar
 
Dries committed
1019
/**
Dries's avatar
 
Dries committed
1020
 * @defgroup format Formatting
Dries's avatar
 
Dries committed
1021
 * @{
Dries's avatar
 
Dries committed
1022
 * Functions to format numbers, strings, dates, etc.
Dries's avatar
 
Dries committed
1023 1024
 */

Dries's avatar
 
Dries committed
1025 1026 1027 1028 1029
/**
 * Formats an RSS channel.
 *
 * Arbitrary elements may be added using the $args associative array.
 */
1030 1031 1032
function format_rss_channel($title, $link, $description, $items, $langcode = NULL, $args = array()) {
  global $language;
  $langcode = $langcode ? $langcode : $language->language;
Dries's avatar
 
Dries committed
1033

Dries's avatar
Dries committed
1034
  $output = "<channel>\n";
1035 1036
  $output .= ' <title>' . check_plain($title) . "</title>\n";
  $output .= ' <link>' . check_url($link) . "</link>\n";
1037 1038 1039 1040

  // 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;).
1041 1042
  $output .= ' <description>' . check_plain(decode_entities(strip_tags($description))) . "</description>\n";
  $output .= ' <language>' . check_plain($langcode) . "</language>\n";
1043
  $output .= format_xml_elements($args);
Dries's avatar
 
Dries committed
1044 1045 1046 1047 1048 1049
  $output .= $items;
  $output .= "</channel>\n";

  return $output;
}

Dries's avatar
 
Dries committed
1050 1051 1052 1053 1054
/**
 * Format a single RSS item.
 *
 * Arbitrary elements may be added using the $args associative array.
 */
Dries's avatar
 
Dries committed
1055
function format_rss_item($title, $link, $description, $args = array()) {
Dries's avatar
Dries committed
1056
  $output = "<item>\n";
1057 1058 1059
  $output .= ' <title>' . check_plain($title) . "</title>\n";
  $output .= ' <link>' . check_url($link) . "</link>\n";
  $output .= ' <description>' . check_plain($description) . "</description>\n";
1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080
  $output .= format_xml_elements($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) {
1081
  $output = '';
1082 1083
  foreach ($array as $key => $value) {
    if (is_numeric($key)) {
Dries's avatar
 
Dries committed
1084
      if ($value['key']) {
1085
        $output .= ' <' . $value['key'];
1086
        if (isset($value['attributes']) && is_array($value['attributes'])) {
Dries's avatar
 
Dries committed
1087 1088 1089
          $output .= drupal_attributes($value['attributes']);
        }