<?php


  static $file_directory, $languages = array();

  if (!isset($file_directory)) {
    $file_directory = variable_get('file_directory_path', 'files') .'/';
  }

  // Never rewrite URLs pointing into the files directory.
  if ($result != '' && strncmp($result, $file_directory, strlen($file_directory))) {
    static $no_src, $custom_url_alter_map = array();

    // Check $no_src for this $result in case we have already determined earlier
    // that there is no path with this alias.
    if (isset($no_src[$result])) {
      return;
    }

    // Check $custom_url_alter_map for this $result in case we have already determined earlier
    // the alias
    if (isset($custom_url_alter_map[$path])) {
      return;
    }

    // Special case where the full path was already matched by
    // drupal_lookup_path(). Add to $custom_url_alter_map to avoid unnecessary future lookups.
    if ($result != $path) {
      $custom_url_alter_map[$path] = $result;
      return;
    }

    $slash = strpos($path, '/');

    if ($slash !== FALSE) {
      $sub_path = substr($path, $slash+1);
      $sub_prefix = substr($path, 0, $slash);
      $sub_lang = FALSE;

      if (!count($languages)) {
        $languages = language_list(); // All enabled languages
      }
      foreach ($languages as $language) {
        $language_prefix = $language->prefix ? $language->prefix : $language->language;
        if ($sub_prefix == $language_prefix && $language->enabled) {
          $sub_lang = $language_prefix;
          break;
        }
      }

      if ($sub_lang) {
        if ($test_path = drupal_lookup_path('source', $sub_path, $sub_lang)) {
          $result = $test_path;
          $custom_url_alter_map[$path] = $result;
        }
      }
    }
  }