common.inc 41 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 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53
/**
 * Set content for a specified region.
 *
 * @param $region
 *   Page region the content is assigned to.
 *
 * @param $data
 *   Content to be set.
 */
function drupal_set_content($region = null, $data = null) {
  static $content = array();

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

/**
 * Get assigned content.
 *
 * @param $region
 *   A specified region to fetch content for.  If null, all regions will be returned.
 *
 * @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";
118
  $output .= theme('stylesheet_import', base_path() .'misc/drupal.css');
Dries's avatar
Dries committed
119 120 121
  return $output . drupal_set_html_head();
}

122
/**
123
 * Reset the static variable which holds the aliases mapped for this request.
124
 */
125 126
function drupal_clear_path_cache() {
  drupal_lookup_path('wipe');
127
}
128

Dries's avatar
Dries committed
129
/**
130
 * Set an HTTP response header for the current page.
Dries's avatar
Dries committed
131 132
 */
function drupal_set_header($header = NULL) {
133
  // We use an array to guarantee there are no leading or trailing delimiters.
134
  // Otherwise, header('') could get called when serving the page later, which
135 136
  // ends HTTP headers prematurely on some PHP versions.
  static $stored_headers = array();
Dries's avatar
Dries committed
137

138
  if (strlen($header)) {
Dries's avatar
Dries committed
139
    header($header);
140
    $stored_headers[] = $header;
Dries's avatar
Dries committed
141
  }
142
  return implode("\n", $stored_headers);
Dries's avatar
Dries committed
143 144
}

145 146 147
/**
 * Get the HTTP response headers for the current page.
 */
Dries's avatar
Dries committed
148 149 150 151
function drupal_get_headers() {
  return drupal_set_header();
}

152 153 154
/**
 * @name HTTP handling
 * @{
155
 * Functions to properly handle HTTP responses.
156 157
 */

158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197
/**
 * 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 $urlencode
 *   If TRUE, the keys and values are both urlencoded.
 * @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 => $value) {
    if ($parent) {
      $key = $parent .'['. urlencode($key) .']';
    }
    else {
      $key = urlencode($key);
    }

    if (in_array(urldecode($key), $exclude)) {
      continue;
    }

    if (is_array($value)) {
      $params[] = drupal_query_string_encode($value, $exclude, $key);
    }
    else {
      $params[] = $key .'='. urlencode($value);
    }
  }

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

198 199
/**
 * Prepare a destination query string for use in combination with
200 201 202 203 204
 * 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
 * is returned.  As such, a destination can persist across multiple
 * pages.
205 206 207 208
 *
 * @see drupal_goto()
 */
function drupal_get_destination() {
209 210 211 212
  if ($_REQUEST['destination']) {
    return 'destination='. urlencode($_REQUEST['destination']);
  }
  else {
213
    $path = $_GET['q'];
214 215 216
    $query = drupal_query_string_encode($_GET, array('q'));
    if ($query != '') {
      $path .= '?'. $query;
217
    }
218
    return 'destination='. urlencode($path);
219 220 221
  }
}

222
/**
223
 * Send the user to a different Drupal page.
224
 *
225 226
 * This issues an on-site HTTP redirect. The function makes sure the redirected
 * URL is formatted correctly.
227
 *
228 229 230 231 232 233 234 235 236 237
 * Usually the redirected URL is constructed from this function's input
 * parameters.  However you may override that behavior by setting a
 * <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
 * 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
 * a post on the 'admin/node'-page or after having logged on using the
 * 'user login'-block in a sidebar.  The function drupal_get_destination()
 * can be used to help set the destination URL.
 *
238 239 240 241 242 243 244 245 246 247 248 249 250
 * 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
 *   A Drupal path.
 * @param $query
 *   The query string component, if any.
 * @param $fragment
 *   The destination fragment identifier (named anchor).
251 252
 *
 * @see drupal_get_destination()
253
 */
254
function drupal_goto($path = '', $query = NULL, $fragment = NULL) {
255
  if (isset($_REQUEST['destination'])) {
256 257
    extract(parse_url($_REQUEST['destination']));
  }
258
  else if (isset($_REQUEST['edit']['destination'])) {
259 260 261
    extract(parse_url($_REQUEST['edit']['destination']));
  }

262
  $url = url($path, $query, $fragment, TRUE);
263

264 265 266 267
  // Before the redirect, allow modules to react to the end of the page request.
  module_invoke_all('exit', $url);

  header('Location: '. $url);
268

269 270 271
  // The "Location" header sends a REDIRECT status code to the http
  // daemon. In some cases this can go wrong, so we make sure none
  // of the code below the drupal_goto() call gets executed when we redirect.
272 273 274
  exit();
}

275
/**
276
 * Generates a site off-line message
277 278
 */
function drupal_site_offline() {
279
  drupal_set_header('HTTP/1.0 503 Service unavailable');
280
  drupal_set_title(t('Site off-line'));
281 282
  print theme('maintenance_page', filter_xss_admin(variable_get('site_offline_message',
    t('%site is currently under maintenance. We should be back shortly. Thank you for your patience.', array('%site' => variable_get('site_name', t('This Drupal site')))))));
283 284
}

285 286 287
/**
 * Generates a 404 error if the request can not be handled.
 */
288
function drupal_not_found() {
289
  drupal_set_header('HTTP/1.0 404 Not Found');
290
  watchdog('page not found', t('%page not found.', array('%page' => theme('placeholder', $_GET['q']))), WATCHDOG_WARNING);
291

292 293 294 295 296
  // Keep old path for reference
  if (!isset($_REQUEST['destination'])) {
    $_REQUEST['destination'] = $_GET['q'];
  }

297
  $path = drupal_get_normal_path(variable_get('site_404', ''));
298
  if ($path && $path != $_GET['q']) {
299
    menu_set_active_item($path);
300
    $return = menu_execute_active_handler();
301
  }
302
  else {
303
    // Redirect to a non-existent menu item to make possible tabs disappear.
304
    menu_set_active_item('');
305
  }
306

307
  if (empty($return)) {
308
    drupal_set_title(t('Page not found'));
309
  }
310
  print theme('page', $return);
311
}
312

313 314 315 316
/**
 * Generates a 403 error if the request is not allowed.
 */
function drupal_access_denied() {
317
  drupal_set_header('HTTP/1.0 403 Forbidden');
318
  watchdog('access denied', t('%page denied access.', array('%page' => theme('placeholder', $_GET['q']))), WATCHDOG_WARNING, l(t('view'), $_GET['q']));
319

320 321 322 323 324
  // Keep old path for reference
  if (!isset($_REQUEST['destination'])) {
    $_REQUEST['destination'] = $_GET['q'];
  }

325
  $path = drupal_get_normal_path(variable_get('site_403', ''));
326
  if ($path && $path != $_GET['q']) {
327
    menu_set_active_item($path);
328
    $return = menu_execute_active_handler();
329
  }
330
  else {
331
    // Redirect to a non-existent menu item to make possible tabs disappear.
332
    menu_set_active_item('');
333
  }
334

335
  if (empty($return)) {
336
    drupal_set_title(t('Access denied'));
337
    $return = t('You are not authorized to access this page.');
338
  }
339
  print theme('page', $return);
340 341
}

342
/**
343
 * Perform an HTTP request.
344
 *
345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361
 * 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 $retry
 *   An integer representing how many times to retry the request in case of a
 *   redirect.
 * @return
 *   An object containing the HTTP request headers, response code, headers,
 *   data, and redirect status.
362 363
 */
function drupal_http_request($url, $headers = array(), $method = 'GET', $data = NULL, $retry = 3) {
364 365
  $result = new StdClass();

366
  // Parse the URL, and make sure we can handle the schema.
367 368 369
  $uri = parse_url($url);
  switch ($uri['scheme']) {
    case 'http':
370
      $port = isset($uri['port']) ? $uri['port'] : 80;
371
      $host = $uri['host'] . ($port != 80 ? ':'. $port : '');
372
      $fp = @fsockopen($uri['host'], $port, $errno, $errstr, 15);
373 374
      break;
    case 'https':
375
      // Note: Only works for PHP 4.3 compiled with OpenSSL.
376
      $port = isset($uri['port']) ? $uri['port'] : 443;
377
      $host = $uri['host'] . ($port != 443 ? ':'. $port : '');
378
      $fp = @fsockopen('ssl://'. $uri['host'], $port, $errno, $errstr, 20);
379 380
      break;
    default:
381
      $result->error = 'invalid schema '. $uri['scheme'];
382 383 384
      return $result;
  }

385
  // Make sure the socket opened properly.
386
  if (!$fp) {
387
    $result->error = trim($errno .' '. $errstr);
388 389 390
    return $result;
  }

391
  // Construct the path to act on.
392 393
  $path = isset($uri['path']) ? $uri['path'] : '/';
  if (isset($uri['query'])) {
394
    $path .= '?'. $uri['query'];
395 396
  }

397
  // Create HTTP request.
398
  $defaults = array(
399 400 401 402
    // 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: $host",
403
    'User-Agent' => 'User-Agent: Drupal (+http://drupal.org/)',
404
    'Content-Length' => 'Content-Length: '. strlen($data)
405 406 407
  );

  foreach ($headers as $header => $value) {
408
    $defaults[$header] = $header .': '. $value;
409 410
  }

411
  $request = $method .' '. $path ." HTTP/1.0\r\n";
412 413 414
  $request .= implode("\r\n", $defaults);
  $request .= "\r\n\r\n";
  if ($data) {
415
    $request .= $data ."\r\n";
416 417 418 419 420 421
  }
  $result->request = $request;

  fwrite($fp, $request);

  // Fetch response.
422
  $response = '';
423 424
  while (!feof($fp) && $chunk = fread($fp, 1024)) {
    $response .= $chunk;
425 426 427 428
  }
  fclose($fp);

  // Parse response.
429 430
  list($split, $result->data) = explode("\r\n\r\n", $response, 2);
  $split = preg_split("/\r\n|\n|\r/", $split);
431

432
  list($protocol, $code, $text) = explode(' ', trim(array_shift($split)), 3);
433 434 435
  $result->headers = array();

  // Parse headers.
436
  while ($line = trim(array_shift($split))) {
437
    list($header, $value) = explode(':', $line, 2);
438 439 440 441 442 443 444 445
    if (isset($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);
    }
446 447 448 449 450 451 452 453 454 455
  }

  $responses = array(
    100 => 'Continue', 101 => 'Switching Protocols',
    200 => 'OK', 201 => 'Created', 202 => 'Accepted', 203 => 'Non-Authoritative Information', 204 => 'No Content', 205 => 'Reset Content', 206 => 'Partial Content',
    300 => 'Multiple Choices', 301 => 'Moved Permanently', 302 => 'Found', 303 => 'See Other', 304 => 'Not Modified', 305 => 'Use Proxy', 307 => 'Temporary Redirect',
    400 => 'Bad Request', 401 => 'Unauthorized', 402 => 'Payment Required', 403 => 'Forbidden', 404 => 'Not Found', 405 => 'Method Not Allowed', 406 => 'Not Acceptable', 407 => 'Proxy Authentication Required', 408 => 'Request Time-out', 409 => 'Conflict', 410 => 'Gone', 411 => 'Length Required', 412 => 'Precondition Failed', 413 => 'Request Entity Too Large', 414 => 'Request-URI Too Large', 415 => 'Unsupported Media Type', 416 => 'Requested range not satisfiable', 417 => 'Expectation Failed',
    500 => 'Internal Server Error', 501 => 'Not Implemented', 502 => 'Bad Gateway', 503 => 'Service Unavailable', 504 => 'Gateway Time-out', 505 => 'HTTP Version not supported'
  );
  // RFC 2616 states that all unknown HTTP codes must be treated the same as
456
  // the base code in their class.
457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483
  if (!isset($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;
}
484 485 486
/**
 * @} End of "HTTP handling".
 */
487

488
/**
489 490
 * Log errors as defined by administrator
 * Error levels:
491 492
 *  0 = Log errors to database.
 *  1 = Log errors to database and to screen.
493
 */
494
function error_handler($errno, $message, $filename, $line) {
495
  if ($errno & (E_ALL ^ E_NOTICE)) {
496 497
    $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');
    $entry = $types[$errno] .': '. $message .' in '. $filename .' on line '. $line .'.';
498

499 500
    // Note: force display of error messages in update.php
    if (variable_get('error_level', 1) == 1 || strstr($_SERVER['PHP_SELF'], 'update.php')) {
501
      drupal_set_message($entry, 'error');
Dries's avatar
Dries committed
502
    }
503 504

    watchdog('php', t('%message in %file on line %line.', array('%error' => $types[$errno], '%message' => $message, '%file' => $filename, '%line' => $line)), WATCHDOG_ERROR);
Dries's avatar
Dries committed
505 506 507
  }
}

508
function _fix_gpc_magic(&$item) {
Dries's avatar
Dries committed
509
  if (is_array($item)) {
Kjartan's avatar
Kjartan committed
510 511 512
    array_walk($item, '_fix_gpc_magic');
  }
  else {
Kjartan's avatar
Kjartan committed
513
    $item = stripslashes($item);
514 515 516
  }
}

517 518 519 520
/**
 * Correct double-escaping problems caused by "magic quotes" in some PHP
 * installations.
 */
521 522
function fix_gpc_magic() {
  static $fixed = false;
523
  if (!$fixed && ini_get('magic_quotes_gpc')) {
Dries's avatar
Dries committed
524 525 526 527 528 529
    array_walk($_GET, '_fix_gpc_magic');
    array_walk($_POST, '_fix_gpc_magic');
    array_walk($_COOKIE, '_fix_gpc_magic');
    array_walk($_REQUEST, '_fix_gpc_magic');
    $fixed = true;
  }
530 531
}

532 533 534
/**
 * @name Messages
 * @{
535
 * Frequently used messages.
536
 */
537 538 539 540

/**
 * Return a string with a "not applicable" message.
 */
Dries's avatar
Dries committed
541
function message_na() {
542
  return t('n/a');
Dries's avatar
Dries committed
543 544
}

545 546 547
/**
 * @} End of "Messages".
 */
Dries's avatar
Dries committed
548

549 550 551
/**
 * Initialize the localization system.
 */
552 553
function locale_initialize() {
  global $user;
554 555 556 557 558

  if (function_exists('i18n_get_lang')) {
    return i18n_get_lang();
  }

559 560 561 562 563
  if (function_exists('locale')) {
    $languages = locale_supported_languages();
    $languages = $languages['name'];
  }
  else {
564 565 566
    // Ensure the locale/language is correctly returned, even without locale.module.
    // Useful for e.g. XML/HTML 'lang' attributes.
    $languages = array('en' => 'English');
567
  }
568
  if ($user->uid && isset($languages[$user->language])) {
569 570 571 572 573
    return $user->language;
  }
  else {
    return key($languages);
  }
574 575
}

576
/**
577
 * Translate strings to the current locale.
578
 *
579
 * When using t(), try to put entire sentences and strings in one t() call.
580 581 582 583
 * This makes it easier for translators. HTML markup within translation strings
 * is acceptable, if necessary. The suggested syntax for a link embedded
 * within a translation string is:
 * @code
584 585 586
 *   $msg = t('You must log in below or <a href="%url">create a new
 *             account</a> before viewing the next page.', array('%url'
 *             => url('user/register')));
587
 * @endcode
588 589 590
 * We suggest the same syntax for links to other sites. This makes it easy to
 * change link URLs if needed (which happens often) without requiring updates
 * to translations.
591
 *
592
 * @param $string
593
 *   A string containing the English string to translate.
594 595
 * @param $args
 *   An associative array of replacements to make after translation. Incidences
596
 *   of any key in this array are replaced with the corresponding value.
597 598
 * @return
 *   The translated string.
599
 */
600
function t($string, $args = 0) {
601 602 603 604
  global $locale;
  if (function_exists('locale') && $locale != 'en') {
    $string = locale($string);
  }
605

606 607
  if (!$args) {
    return $string;
Kjartan's avatar
Kjartan committed
608 609
  }
  else {
610 611
    return strtr($string, $args);
  }
612 613
}

614
/**
615
 * @defgroup validation Input validation
616
 * @{
617
 * Functions to validate user input.
618 619
 */

620
/**
621 622 623
 * Verify the syntax of the given e-mail address.
 *
 * Empty e-mail addresses are allowed. See RFC 2822 for details.
624
 *
625
 * @param $mail
626
 *   A string containing an e-mail address.
627
 * @return
628
 *   TRUE if the address is in a valid format.
629
 */
630
function valid_email_address($mail) {
631
  $user = '[a-zA-Z0-9_\-\.\+\^!#\$%&*+\/\=\?\`\|\{\}~\']+';
632
  $domain = '(?:(?:[a-zA-Z0-9]|[a-zA-Z0-9][a-zA-Z0-9\-]*[a-zA-Z0-9])\.?)+';
633 634 635
  $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
636
  return preg_match("/^$user@($domain|(\[($ipv4|$ipv6)\]))$/", $mail);
637 638
}

639 640 641
/**
 * Verify the syntax of the given URL.
 *
642
 * @param $url
643
 *   The URL to verify.
644
 * @param $absolute
645
 *   Whether the URL is absolute (beginning with a scheme such as "http:").
646
 * @return
647
 *   TRUE if the URL is in a valid format.
648
 */
649
function valid_url($url, $absolute = FALSE) {
650
  $allowed_characters = '[a-z0-9\/:_\-_\.\?\$,~=#&%\+]';
651
  if ($absolute) {
652
    return preg_match("/^(http|https|ftp):\/\/". $allowed_characters ."+$/i", $url);
653 654
  }
  else {
655
    return preg_match("/^". $allowed_characters ."+$/i", $url);
656
  }
657 658
}

659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685
/**
 * 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) {
  db_query("INSERT INTO {flood} (event, hostname, timestamp) VALUES ('%s', '%s', %d)", $name, $_SERVER['REMOTE_ADDR'], time());
}

/**
 * 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 $number
 *   The maximum number of the specified event per hour (per visitor).
 * @return
 *   True if the user did not exceed the hourly threshold.  False otherwise.
 */
function flood_is_allowed($name, $threshold) {
  $number = db_num_rows(db_query("SELECT event FROM {flood} WHERE event = '%s' AND hostname = '%s' AND timestamp > %d", $name, $_SERVER['REMOTE_ADDR'], time() - 3600));
  return ($number < $threshold ? TRUE : FALSE);
}

686 687
function check_file($filename) {
  return is_uploaded_file($filename);
Dries's avatar
Dries committed
688 689
}

Dries's avatar
Dries committed
690 691 692 693 694
/**
 * Prepare a URL for use in an HTML attribute. Strips harmful protocols.
 *
 */
function check_url($uri) {
695
  return filter_xss_bad_protocol($uri, FALSE);
Dries's avatar
Dries committed
696 697
}

698
/**
699
 * @defgroup format Formatting
700
 * @{
701
 * Functions to format numbers, strings, dates, etc.
702 703
 */

704 705 706 707 708 709
/**
 * Formats an RSS channel.
 *
 * Arbitrary elements may be added using the $args associative array.
 */
function format_rss_channel($title, $link, $description, $items, $language = 'en', $args = array()) {
Dries's avatar
Dries committed
710 711
  // arbitrary elements may be added using the $args associative array

Dries's avatar
Dries committed
712
  $output = "<channel>\n";
713 714
  $output .= ' <title>'. check_plain($title) ."</title>\n";
  $output .= ' <link>'. check_url($link) ."</link>\n";
715 716 717 718 719

  // 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";
720
  $output .= ' <language>'. check_plain($language) ."</language>\n";
Dries's avatar
Dries committed
721
  foreach ($args as $key => $value) {
722
    $output .= ' <'. $key .'>'. check_plain($value) ."</$key>\n";
Dries's avatar
Dries committed
723
  }
Dries's avatar
Dries committed
724 725 726 727 728 729
  $output .= $items;
  $output .= "</channel>\n";

  return $output;
}

730 731 732 733 734
/**
 * Format a single RSS item.
 *
 * Arbitrary elements may be added using the $args associative array.
 */
Dries's avatar
Dries committed
735
function format_rss_item($title, $link, $description, $args = array()) {
Dries's avatar
Dries committed
736
  $output = "<item>\n";
737 738 739
  $output .= ' <title>'. check_plain($title) ."</title>\n";
  $output .= ' <link>'. check_url($link) ."</link>\n";
  $output .= ' <description>'. check_plain($description) ."</description>\n";
Dries's avatar
Dries committed
740
  foreach ($args as $key => $value) {
741 742 743
    if (is_array($value)) {
      if ($value['key']) {
        $output .= ' <'. $value['key'];
744
        if (isset($value['attributes']) && is_array($value['attributes'])) {
745 746 747 748 749 750 751 752 753 754 755 756
          $output .= drupal_attributes($value['attributes']);
        }

        if ($value['value']) {
          $output .= '>'. $value['value'] .'</'. $value['key'] .">\n";
        }
        else {
          $output .= " />\n";
        }
      }
    }
    else {
757
      $output .= ' <'. $key .'>'. check_plain($value) ."</$key>\n";
758
    }
Dries's avatar
Dries committed
759
  }
Dries's avatar
Dries committed
760 761 762 763 764
  $output .= "</item>\n";

  return $output;
}

765
/**
766
 * Format a string containing a count of items.
767
 *
768 769 770 771 772 773 774 775 776 777 778 779 780 781
 * 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.
 *
 * @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").
 * @param $plural
 *   The string for the plural case. Please make sure it is clear this is plural,
 *   to ease translation. Use %count in place of the item count, as in "%count
 *   new comments".
 * @return
 *   A translated string.
782
 */
Dries's avatar
Dries committed
783
function format_plural($count, $singular, $plural) {
784
  if ($count == 1) return t($singular, array("%count" => $count));
785 786

  // get the plural index through the gettext formula
787
  $index = (function_exists('locale_get_plural')) ? locale_get_plural($count) : -1;
788 789 790 791 792 793
  if ($index < 0) { // backward compatibility
    return t($plural, array("%count" => $count));
  }
  else {
    switch ($index) {
      case "0":
794
        return t($singular, array("%count" => $count));
795 796 797 798 799 800
      case "1":
        return t($plural, array("%count" => $count));
      default:
        return t(strtr($plural, array("%count" => '%count['. $index .']')), array('%count['. $index .']' => $count));
    }
  }
Dries's avatar
Dries committed
801 802
}

803
/**
804
 * Generate a string representation for the given byte count.
805
 *
806 807 808 809
 * @param $size
 *   The size in bytes.
 * @return
 *   A translated string representation of the size.
810
 */
Dries's avatar
Dries committed
811
function format_size($size) {
812
  $suffix = t('bytes');
813
  if ($size >= 1024) {
Dries's avatar
Dries committed
814
    $size = round($size / 1024, 2);
815
    $suffix = t('KB');
Dries's avatar
Dries committed
816
  }
817
  if ($size >= 1024) {
Dries's avatar
Dries committed
818
    $size = round($size / 1024, 2);
819
    $suffix = t('MB');
Dries's avatar
Dries committed
820
  }
821
  return t('%size %suffix', array('%size' => $size, '%suffix' => $suffix));
Dries's avatar
Dries committed
822 823
}

824
/**
825
 * Format a time interval with the requested granularity.
826
 *
827 828 829 830 831 832
 * @param $timestamp
 *   The length of the interval in seconds.
 * @param $granularity
 *   How many different units to display in the string.
 * @return
 *   A translated string representation of the interval.
833
 */
834
function format_interval($timestamp, $granularity = 2) {
835
  $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);
836
  $output = '';
837
  foreach ($units as $key => $value) {
838
    $key = explode('|', $key);
Dries's avatar
Dries committed
839
    if ($timestamp >= $value) {
840
      $output .= ($output ? ' ' : '') . format_plural(floor($timestamp / $value), $key[0], $key[1]);
Dries's avatar
Dries committed
841
      $timestamp %= $value;
842 843 844 845 846
      $granularity--;
    }

    if ($granularity == 0) {
      break;
Dries's avatar
Dries committed
847 848
    }
  }
849
  return $output ? $output : t('0 sec');
Dries's avatar
Dries committed
850 851
}

852
/**
853 854
 * Format a date with the given configured format or a custom format string.
 *
855 856 857 858
 * 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.
 *
859 860 861 862 863 864
 * @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
865 866 867
 *   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.
868 869 870 871
 * @param $timezone
 *   Time zone offset in seconds; if omitted, the user's time zone is used.
 * @return
 *   A translated date string in the requested format.
872
 */
873
function format_date($timestamp, $type = 'medium', $format = '', $timezone = NULL) {
874
  if (!isset($timezone)) {
875
    global $user;
Steven Wittens's avatar
Steven Wittens committed
876 877 878 879 880 881
    if (variable_get('configurable_timezones', 1) && $user->uid && strlen($user->timezone)) {
      $timezone = $user->timezone;
    }
    else {
      $timezone = variable_get('date_default_timezone', 0);
    }
882
  }
Dries's avatar
Dries committed
883

884
  $timestamp += $timezone;
Dries's avatar
Dries committed
885 886

  switch ($type) {
887 888
    case 'small':
      $format = variable_get('date_format_short', 'm/d/Y - H:i');
Dries's avatar
Dries committed
889
      break;
890 891
    case 'large':
      $format = variable_get('date_format_long', 'l, F j, Y - H:i');
Dries's avatar
Dries committed
892
      break;
893
    case 'custom':
894
      // No change to format
Dries's avatar
Dries committed
895
      break;
896
    case 'medium':
Dries's avatar
Dries committed
897
    default:
898
      $format = variable_get('date_format_medium', 'D, m/d/Y - H:i');
899 900
  }

901
  $max = strlen($format);
902
  $date = '';
903
  for ($i = 0; $i < $max; $i++) {
904
    $c = $format[$i];
905
    if (strpos('AaDFlM', $c) !== false) {
906
      $date .= t(gmdate($c, $timestamp));
907
    }
908
    else if (strpos('BdgGhHiIjLmnsStTUwWYyz', $c) !== false) {
909 910 911 912
      $date .= gmdate($c, $timestamp);
    }
    else if ($c == 'r') {
      $date .= format_date($timestamp - $timezone, 'custom', 'D, d M Y H:i:s O', $timezone);
913
    }
914 915 916 917 918
    else if ($c == 'O') {
      $date .= sprintf('%s%02d%02d', ($timezone < 0 ? '-' : '+'), abs($timezone / 3600), abs($timezone % 3600) / 60);
    }
    else if ($c == 'Z') {
      $date .= $timezone;
919
    }
920 921 922
    else if ($c == '\\') {
      $date .= $format[++$i];
    }
923
    else {
924
      $date .= $c;
925
    }
Dries's avatar
Dries committed
926
  }
927

Dries's avatar
Dries committed
928 929 930
  return $date;
}

931 932 933
/**
 * @} End of "defgroup format".
 */
Dries's avatar
Dries committed
934

935
/**
936
 * Generate a URL from a Drupal menu path. Will also pass-through existing URLs.
937 938
 *
 * @param $path
939 940
 *   The Drupal path being linked to, such as "admin/node", or an existing URL
 *   like "http://drupal.org/".
941
 * @param $query
942
 *   A query string to append to the link or URL.
943
 * @param $fragment
944 945 946
 *   A fragment identifier (named anchor) to append to the link. If an existing
 *   URL with a fragment identifier is used, it will be replaced. Note, do not
 *   include the '#'.
947 948
 * @param $absolute
 *   Whether to force the output to be an absolute link (beginning with http:).
949 950
 *   Useful for links that will be displayed outside the site, such as in an
 *   RSS feed.
951 952 953 954 955 956 957
 * @return
 *   an HTML string containing a link to the given path.
 *
 * When creating links in modules, consider whether l() could be a better
 * alternative than url().
 */
function url($path = NULL, $query = NULL, $fragment = NULL, $absolute = FALSE) {
958 959 960 961 962 963
  if (isset($fragment)) {
    $fragment = '#'. $fragment;
  }

  // Return an external link if $path contains an allowed absolute URL.
  // Only call the slow filter_xss_bad_protocol if $path contains a ':'.
964
  if (strpos($path, ':') !== FALSE && filter_xss_bad_protocol($path, FALSE) == check_plain($path)) {
965 966 967 968 969 970 971 972 973 974 975 976 977 978
    // Split off the fragment
    if (strpos($path, '#')) {
      list($path, $old_fragment) = explode('#', $path, 2);
      if (isset($old_fragment) && !isset($fragment)) {
        $fragment = '#'. $old_fragment;
      }
    }
    // Append the query
    if (isset($query)) {
      $path .= (strpos($path, '?') ? '&' : '?') . $query;
    }
    // Reassemble
    return $path . $fragment;
  }
Dries's avatar
Dries committed
979

980
  global $base_url;
981
  static $script;
982
  static $clean_url;
983 984

  if (empty($script)) {
985 986 987
    // On some web servers, such as IIS, we can't omit "index.php".  So, we
    // generate "index.php?q=foo" instead of "?q=foo" on anything that is not
    // Apache.
988
    $script = (strpos($_SERVER['SERVER_SOFTWARE'], 'Apache') === false) ? 'index.php' : '';
989
  }
990

991
  // Cache the clean_url variable to improve performance.
992 993
  if (!isset($clean_url)) {
    $clean_url = (bool)variable_get('clean_url', '0');
994
  }
995

996
  $base = ($absolute ? $base_url . '/' : base_path());
Dries's avatar
Dries committed
997

998 999 1000 1001 1002
  // The special path '<front>' links to the default front page.
  if (isset($path) && $path != '<front>') {
    $path = drupal_get_path_alias($path);
    $path = drupal_urlencode($path);
    if (!$clean_url) {
Dries's avatar
Dries committed
1003
      if (isset($query)) {
1004
        return $base . $script .'?q='. $path .'&'. $query . $fragment;
Dries's avatar
Dries committed
1005 1006
      }
      else {
1007
        return $base . $script .'?q='. $path . $fragment;
Dries's avatar
Dries committed
1008
      }
1009 1010
    }
    else {
Dries's avatar
Dries committed
1011
      if (isset($query)) {
1012
        return $base . $path .'?'. $query . $fragment;
Dries's avatar
Dries committed
1013 1014
      }
      else {
1015
        return $base . $path . $fragment;
Dries's avatar
Dries committed
1016
      }
1017 1018 1019
    }
  }
  else {
1020 1021
    if (isset($query)) {
      return $base . $script .'?'. $query . $fragment;
1022
    }
1023
    else {
1024
      return $base . $fragment;
1025
    }
1026
  }
1027 1028
}

1029 1030 1031 1032 1033 1034 1035 1036
/**
 * Format an attribute string to insert in a tag.
 *
 * @param $attributes
 *   An associative array of HTML attributes.
 * @return
 *   An HTML string ready for insertion in a tag.
 */
1037
function drupal_attributes($attributes = array()) {
1038
  if (is_array($attributes)) {
1039
    $t = '';
1040
    foreach ($attributes as $key => $value) {
1041
      $t .= " $key=".'"'. check_plain($value) .'"';
1042
    }
Dries's avatar