Helper function used to cache the language negotiation providers results.

Parameters

$provider_id: The language negotiation provider's identifier.

$provider: (optional) An associative array of information about the provider to be invoked (see hook_language_negotiation_info() for details). If not passed in, it will be loaded through language_negotiation_info().

Return value

A language object representing the language chosen by the provider.

Related topics

File

drupal-7.x/includes/language.inc, line 427

Language Negotiation API.

Code

function language_provider_invoke($provider_id, $provider = NULL) {
  $results = &drupal_static(__FUNCTION__);

  if (!isset($results[$provider_id])) {
    global $user;

    // Get languages grouped by status and select only the enabled ones.
    $languages = language_list('enabled');
    $languages = $languages[1];

    if (!isset($provider)) {
      $providers = language_negotiation_info();
      $provider = $providers[$provider_id];
    }

    if (isset($provider['file'])) {
      require_once DRUPAL_ROOT . '/' . $provider['file'];
    }

    // If the language negotiation provider has no cache preference or this is
    // satisfied we can execute the callback.
    $cache = !isset($provider['cache']) || $user->uid || $provider['cache'] == variable_get('cache', 0);
    $callback = isset($provider['callbacks']['language']) ? $provider['callbacks']['language'] : FALSE;
    $langcode = $cache && function_exists($callback) ? $callback($languages) : FALSE;
    $results[$provider_id] = isset($languages[$langcode]) ? $languages[$langcode] : FALSE;
  }

  // Since objects are resources, we need to return a clone to prevent the
  // language negotiation provider cache from being unintentionally altered. The
  // same providers might be used with different language types based on
  // configuration.
  return !empty($results[$provider_id]) ? clone($results[$provider_id]) : $results[$provider_id];
}