function check_markup

Runs all the enabled filters on a piece of text.

Note: Because filters can inject JavaScript or execute PHP code, security is vital here. When a user supplies a text format, you should validate it using filter_access() before accepting/using it. This is normally done in the validation stage of the Form API. You should for example never make a preview of content in a disallowed format.


$text: The text to be filtered.

$format_id: (optional) The machine name of the filter format to be used to filter the text. Defaults to the fallback format. See filter_fallback_format().

$langcode: (optional) The language code of the text to be filtered, e.g. 'en' for English. This allows filters to be language aware so language specific text replacement can be implemented. Defaults to an empty string.

$cache: (optional) A Boolean indicating whether to cache the filtered output in the {cache_filter} table. The caller may set this to FALSE when the output is already cached elsewhere to avoid duplicate cache lookups and storage. Defaults to FALSE.

Return value

The filtered text.

Related topics

15 calls to check_markup()
BlockTestCase::testCustomBlock in drupal/modules/block/block.test
Test creating custom block, moving it to a specific region and then deleting it.
block_block_view in drupal/modules/block/block.module
Implements hook_block_view().
BookTestCase::checkBookNode in drupal/modules/book/book.test
Checks the outline of sub-pages; previous, up, and next.
BookTestCase::testBookExport in drupal/modules/book/book.test
Tests book export ("printer-friendly version") functionality.
comment_submit in drupal/modules/comment/comment.module
Prepare a comment for submission.

... See full list


drupal/modules/filter/filter.module, line 766
Framework for handling the filtering of content.


function check_markup($text, $format_id = NULL, $langcode = '', $cache = FALSE) {
  if (!isset($format_id)) {
    $format_id = filter_fallback_format();

  // If the requested text format does not exist, the text cannot be filtered.
  if (!($format = filter_format_load($format_id))) {
    watchdog('filter', 'Missing text format: %format.', array(
      '%format' => $format_id,
    return '';

  // Check for a cached version of this piece of text.
  $cache = $cache && !empty($format->cache);
  $cache_id = '';
  if ($cache) {
    $cache_id = $format->format . ':' . $langcode . ':' . hash('sha256', $text);
    if ($cached = cache_get($cache_id, 'cache_filter')) {
      return $cached->data;

  // Convert all Windows and Mac newlines to a single newline, so filters only
  // need to deal with one possibility.
  $text = str_replace(array(
  ), "\n", $text);

  // Get a complete list of filters, ordered properly.
  $filters = filter_list_format($format->format);
  $filter_info = filter_get_filters();

  // Give filters the chance to escape HTML-like data such as code or formulas.
  foreach ($filters as $name => $filter) {
    if ($filter->status && isset($filter_info[$name]['prepare callback']) && function_exists($filter_info[$name]['prepare callback'])) {
      $function = $filter_info[$name]['prepare callback'];
      $text = $function($text, $filter, $format, $langcode, $cache, $cache_id);

  // Perform filtering.
  foreach ($filters as $name => $filter) {
    if ($filter->status && isset($filter_info[$name]['process callback']) && function_exists($filter_info[$name]['process callback'])) {
      $function = $filter_info[$name]['process callback'];
      $text = $function($text, $filter, $format, $langcode, $cache, $cache_id);

  // Cache the filtered text. This cache is infinitely valid. It becomes
  // obsolete when $text changes (which leads to a new $cache_id). It is
  // automatically flushed when the text format is updated.
  // @see filter_format_save()
  if ($cache) {
    cache_set($cache_id, $text, 'cache_filter');
  return $text;