check_markup

Run 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.

Parameters

$text: The text to be filtered.

$format_id: The format id of the text to be filtered. If no format is assigned, the fallback format will be used.

$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.

$cache: Boolean 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.

Related topics

Sanitization functions

Functions to sanitize values.

14 calls to check_markup()

File

core/modules/filter/filter.module, line 728

Framework for handling filtering of content.

Code

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), WATCHDOG_ALERT);
    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('filter')->get($cache_id)) {
      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("\r\n", "\r"), "\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 = $filter_info[$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 = $filter_info[$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('filter')->set($cache_id, $text);
  }

  return $text;
}