modules/xmlsitemap/xmlsitemap.module

<?php
// $Id: xmlsitemap.module,v 1.21 2008/11/17 01:27:10 kiam Exp $

/**
 * @file Creates a site map compatible with the sitemaps.org schema.
 */

/**
 * Implementation of hook_help().
 */
function xmlsitemap_help($path, $arg) {
  switch ($path) {
    case 'admin/settings/xmlsitemap':
    case 'admin/settings/xmlsitemap/settings':
      return t('Configure the site map. Your site map is at !url.', array('!url' => '<a href="'. xmlsitemap_url('sitemap.xml', drupal_lookup_path('alias', 'sitemap.xml') ? drupal_lookup_path('alias', 'sitemap.xml') : NULL, NULL, NULL, TRUE) .'">'. xmlsitemap_url('sitemap.xml', drupal_lookup_path('alias', 'sitemap.xml') ? drupal_lookup_path('alias', 'sitemap.xml') : NULL, NULL, NULL, TRUE) .'</a>'));
    case 'admin/settings/xmlsitemap/engines':
      return t('Configure behavior for search engines.');
    case 'admin/settings/xmlsitemap/additional':
      return t('Set up additional links for your site map.');
  }
}

/**
 * Implementation of hook_menu().
 */
function xmlsitemap_menu() {
  $items = array();
  $access_config = array('administer site configuration');
  $access_content = array('access content');
  $items['admin/settings/xmlsitemap'] = array(
    'title' => 'XML Sitemap',
    'description' => 'Configure site map.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('xmlsitemap_settings_sitemap'),
    'access arguments' => $access_config,
  );
  $items['admin/settings/xmlsitemap/settings'] = array(
    'title' => 'Site map',
    'description' => 'Configure site map.',
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => -1,
  );
  $items['admin/settings/xmlsitemap/engines'] = array(
    'title' => 'Search engines',
    'description' => 'Configure search engines.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('xmlsitemap_settings_engines'),
    'type' => MENU_LOCAL_TASK,
    'access arguments' => $access_config,
  );
  $items['admin/settings/xmlsitemap/additional'] = array(
    'title' => 'Additional',
    'description' => 'Configure additional links.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('xmlsitemap_settings_additional'),
    'type' => MENU_LOCAL_TASK,
    'weight' => 1,
    'access arguments' => $access_config,

  );
  $items['sitemap.xml'] = array(
    'title' => 'Site map index',
    'page callback' => '_xmlsitemap_output',
    'type' => MENU_CALLBACK,
    'access arguments' => $access_content
  );
  $chunk_count = variable_get('xmlsitemap_chunk_count', 0);
  for ($chunk = 0; $chunk < $chunk_count; ++$chunk) {
    $items["sitemap$chunk.xml"] = array(
      'title' => 'Site map !number',
      'title arguments' => array('!number' => $chunk),
      'page callback' => '_xmlsitemap_output',
      'page arguments' => array((string)$chunk),
      'type' => MENU_CALLBACK,
      'access arguments' => $access_content
    );
  }

  return $items;
}

/**
 * Menu callback; return site map settings form.
 */
function xmlsitemap_settings_sitemap() {
  $form['xmlsitemap_chunk_size'] = array(
    '#type' => 'textfield',
    '#title' => t('Chunk size'),
    '#default_value' => variable_get('xmlsitemap_chunk_size', 50000),
    '#size' => 10,
    '#maxlength' => 5,
    '#description' => t('This is the number of links to include in one site map. Values can range between 1 and 50,000. If the total number of links exceeds the chunk size, multiple site maps will be generated.'),
    '#weight' => -1,
  );
  $form['xmlsitemap_front_page_priority'] = array(
    '#type' => 'select',
    '#title' => t('Front page priority'),
    '#default_value' => variable_get('xmlsitemap_front_page_priority', 1),
    '#options' => xmlsitemap_priority_options(),
    '#description' => t('This is the absolute priority for the front page.'),
    '#weight' => -1,
  );
  return system_settings_form($form);
}

/**
 * Validate site map settings form.
 */
function xmlsitemap_settings_sitemap_validate($form, &$form_state) {
  if ($form_state['values']['xmlsitemap_chunk_size'] > 50000) {
    form_set_error('xmlsitemap_chunk_size', t('Cannot send more than 50,000 links at one time.'));
  }
}

/**
 * Submit site map settings form.
 */
function xmlsitemap_settings_sitemap_submit($form, &$form_state) {
  system_settings_form_submit($form, $form_state);
  xmlsitemap_update_sitemap();
}

/**
 * Menu callback; return search engine settings form.
 */
function xmlsitemap_settings_engines() {
  $form['submission'] = array(
    '#type' => 'fieldset',
    '#title' => t('Submission settings'),
  );
  $form['submission']['xmlsitemap_submit'] = array(
    '#type' => 'checkbox',
    '#title' => t('Submit site map when updated.'),
    '#default_value' => variable_get('xmlsitemap_submit', FALSE),
    '#description' => t('If enabled, search engines will be notified of changes to the site map each time it is updated.'),
  );
  $form['submission']['xmlsitemap_cron_submit'] = array(
    '#type' => 'checkbox',
    '#title' => t('Submit site map on cron run.'),
    '#default_value' => variable_get('xmlsitemap_cron_submit', FALSE),
    '#description' => t('If enabled, search engines will be notified of changes to the site map each time cron is run.'),
  );
  $form['submission']['xmlsitemap_log_access'] = array(
    '#type' => 'checkbox',
    '#title' => t('Log access.'),
    '#default_value' => variable_get('xmlsitemap_log_access', FALSE),
    '#description' => t('If enabled, a watchdog entry will be made each time the site map is accessed, containing information about the requestor.'),
  );
  $form = array_merge($form, module_invoke_all('xmlsitemap_engines', 'form'));
  menu_rebuild();
  return system_settings_form($form);
}

/**
 * Submit search engine settings form.
 */
function xmlsitemap_settings_engines_submit($form, &$form_state) {
  if ($form_state['values']['xmlsitemap_root']) {
    $form_state['values']['xmlsitemap_submit'] = FALSE;
    $form_state['values']['xmlsitemap_log_access'] = FALSE;
  }
  system_settings_form_submit($form, $form_state);
}

/**
 * Menu callback; return additional links form.
 */
function xmlsitemap_settings_additional() {
  $form['xmlsitemap_additional_links_priority'] = array(
    '#type' => 'select',
    '#title' => t('Link priority'),
    '#default_value' => variable_get('xmlsitemap_additional_links_priority', 0.5),
    '#options' => xmlsitemap_priority_options(),
    '#description' => t('This is the default priority for additional links.'),
  );
  $form['delete']['#tree'] = TRUE;
  $form['path']['#tree'] = TRUE;
  $form['link']['#tree'] = TRUE;
  $form['link']['new'] = array(
    '#type' => 'textfield',
    '#size' => 40,
    '#description' => t('Enter a Drupal path to add to the site map.'),
    '#attributes' => array('tabindex' => 1),
  );
  $form['old_priority']['#tree'] = TRUE;
  $form['priority']['#tree'] = TRUE;
  $form['priority']['new'] = array(
    '#type' => 'select',
    '#default_value' => 'NULL',
    '#options' => xmlsitemap_priority_options('default'),
    '#attributes' => array('tabindex' => 2),
  );
  $result = pager_query("SELECT path, priority FROM {xmlsitemap_additional} ORDER BY last_changed DESC", 50);
  while ($link = db_fetch_object($result)) {
    $id = $link->path == 'new' ? '_new' : str_replace(array('_', '%'), array('__', '_'), urlencode($link->path));
    $form['delete'][$id] = array('#type' => 'checkbox', '#default_value' => FALSE);
    $form['path'][$id] = array('#type' => 'value', '#value' => $link->path);
    $form['link'][$id] = array('#value' => '<a href="'. xmlsitemap_url($link->path, drupal_lookup_path('alias', $link->path) ? drupal_lookup_path('alias', $link->path) : NULL) .'">'. $link->path .'</a>');
    $priority = isset($link->priority) ? $link->priority : 'NULL';
    $form['old_priority'][$id] = array('#type' => 'value', '#value' => $priority);
    $form['priority'][$id] = array('#type' => 'select', '#default_value' => $priority, '#options' => xmlsitemap_priority_options('default'));
  }
  $form['pager'] = array('#value' => theme('pager', NULL, 50));
  return system_settings_form($form);
}

/**
 * Implementation of hook_theme().
 */
function xmlsitemap_theme() {
  return array(
    'xmlsitemap_settings_additional' => array('form'),
  );
}

/**
 * Theme additional links form.
 * @ingroup themeable
 */
function theme_xmlsitemap_settings_additional($form) {
  $output = '';
  $output .= drupal_render($form['xmlsitemap_additional_links_priority']);
  $header = array(t('Delete'), t('Path'), t('Priority'));
  foreach (element_children($form['link']) as $id) {
    $row = array();
    $row[] = isset($form['delete'][$id]) ? drupal_render($form['delete'][$id]) : array_merge(array('header' => TRUE, 'valign' => 'bottom'), theme('table_select_header_cell'));
    $row[] = drupal_render($form['link'][$id]);
    $row[] = drupal_render($form['priority'][$id]);
    $rows[$id] = array('data' => $row, 'valign' => 'top');
  }
  if (!empty($rows)) {
    $output .= theme('table', $header, $rows);
  }
  $output .= drupal_render($form);
  drupal_add_js('document.getElementById("edit-link-new").focus()', 'inline', 'footer');
  return $output;
}


/**
 * Submit additional links form.
 */
function xmlsitemap_settings_additional_submit($form, &$form_state) {
  $update = FALSE;
  if ($form_state['values']['op'] == t('Save configuration')) {
    if ($form_state['values']['xmlsitemap_additional_links_priority'] != variable_get('xmlsitemap_additional_links_priority', 0.1)) {
      $update = TRUE;
    }
    if (!empty($form_state['values']['delete'])) {
      foreach ($form_state['values']['delete'] as $id => $delete) {
        if ($delete || $form_state['values']['path'][$id] == trim($form_state['values']['link']['new'])) {
          db_query("DELETE FROM {xmlsitemap_additional} WHERE path = '%s'", $form_state['values']['path'][$id]);
          unset($form_state['values']['priority'][$id]);
          $update = TRUE;
        }
      }
      unset($form_state['values']['delete']);
    }
    $path = trim($form_state['values']['link']['new']);
    $pid = db_result(db_query("SELECT pid FROM {url_alias} WHERE src = '%s'", $path));
    if (!empty($path)) {
      db_query("
        INSERT INTO {xmlsitemap_additional} (path, pid, last_changed, priority) VALUES ('%s', %s, %d, %s)
      ", $path, empty($pid) ? 'NULL' : $pid, time(), $form_state['values']['priority']['new']);
      unset($form_state['values']['link'], $form_state['values']['priority']['new']);
      $update = TRUE;
    }
    if (!empty($form_state['values']['priority'])) {
      foreach ($form_state['values']['priority'] as $id => $priority) {
        if ($priority != $form_state['values']['old_priority'][$id]) {
          $pid = db_result(db_query("SELECT pid FROM {url_alias} WHERE src = '%s'", $form_state['values']['path'][$id]));
          db_query("
            UPDATE {xmlsitemap_additional}
            SET pid = %s, previously_changed = last_changed, last_changed = %d, priority = %s
            WHERE path = '%s'
          ", empty($pid) ? 'NULL' : $pid, time(), $priority, $form_state['values']['path'][$id]);
          $update = TRUE;
        }
      }
      unset($form_state['values']['path'], $form_state['values']['priority'], $form_state['values']['old_priority']);
    }
  }
  elseif (variable_get('xmlsitemap_additional_links_priority', 0.1) != 0.1) {
    if (in_array('NULL', $form_state['values']['old_priority'])) {
      $update = TRUE;
    }
    unset($form_state['values']['delete'], $form_state['values']['path'], $form_state['values']['link'], $form_state['values']['old_priority'], $form_state['values']['priority']);
  }
  system_settings_form_submit($form, $form_state);
  if ($update) {
    xmlsitemap_update_sitemap();
  }
}

/**
 * Get an array of site map priority options.
 * @param $option:
 * If not given, the array will include priority values from 0.0 to 1.0.
 * - exclude: Add option to exclude item from site map.
 * - default: Add option to use default priority. Only for cases where a
 *   default priority exists.
 * - both: Add both the default and exclude options.
 * @return An array of priority options.
 */
function xmlsitemap_priority_options($option = NULL) {
  if ($option == 'default' || $option == 'both') {
    $options['NULL'] = t('Default');
  }
  $options['1'] = '1.0';
  $values = array('0.9', '0.8', '0.7', '0.6', '0.5', '0.4', '0.3', '0.2', '0.1');
  foreach ($values as $value) {
    $options[$value] = $value;
  }
  $options['0'] = '0.0';
  if ($option == 'exclude' || $option == 'both') {
    $options['-1'] = t('Not in site map');
  }
  return $options;
}

/**
 * Implementation of hook_robotstxt().
 */
function xmlsitemap_robotstxt() {
  return array("Sitemap: ". xmlsitemap_url('sitemap.xml', drupal_lookup_path('alias', 'sitemap.xml') ? drupal_lookup_path('alias', 'sitemap.xml') : NULL, NULL, NULL, TRUE));
}

/**
 * Menu callback; display the site map.
 * @param $chunk:
 * An integer specifying which chunk of the site map is being requested. If
 * not set and there is more than one chunk, display the site map index.
 * @return None
 */
function _xmlsitemap_output($chunk = NULL) {
  drupal_set_header('Content-type: text/xml; charset=utf-8');
  global $user;
  $dest = file_directory_path() .'/xmlsitemap';
  file_check_directory($dest, FILE_CREATE_DIRECTORY);
  if (isset($chunk)) {
    $dest .= "/sitemap$chunk.xml.gz";
    $type = t('Site map @chunk', array('@chunk' => $chunk));
  }
  else {
    $dest .= '/sitemap.xml.gz';
    $link_count = _xmlsitemap_link_count();
    $chunk_size = variable_get('xmlsitemap_chunk_size', 50000);
    $type = $link_count > $chunk_size ? t('Site map index') : t('Site map');
  }
  $status = TRUE;
  if (!file_exists($dest) || variable_get('xmlsitemap_update', FALSE)) {
    $page = isset($chunk) ? $chunk : 'index';
    $status = _xmlsitemap_update_cache($page);
  }
  if ($status) {
    if (strpos($_SERVER['HTTP_ACCEPT_ENCODING'], 'gzip') === FALSE || zlib_get_coding_type() !== FALSE || extension_loaded('eAccelerator') || (variable_get('cache', CACHE_DISABLED) != CACHE_DISABLED && empty($user->uid))) {
      readgzfile($dest);
    }
    else {
      drupal_set_header('Content-Encoding: gzip');
      print file_get_contents($dest);
    }
    if (variable_get('xmlsitemap_log_access', FALSE)) {
      $message = array_shift(module_invoke_all('xmlsitemap_engines', 'access', $type));
      if (isset($message)) {
        watchdog('xmlsitemap', $message);
      }
      else {
        watchdog('xmlsitemap', '!sitemap downloaded by @user-agent at @address.', array(
          '!sitemap' => $type,
          '@user-agent' => $_SERVER['HTTP_USER_AGENT'],
          '@address' => ip_address(),
        ));
      }
    }
  }
  else {
    drupal_not_found();
  }
}

/**
 * Count the total number of links in the site.
 * @return An integer containing the total number of links
 */
function _xmlsitemap_link_count() {
  static $count;
  $count = isset($count) ? $count : count(_xmlsitemap_links());
  return $count;
}

/**
 * Update the cached site map files.
 * @return TRUE if the update was successful, FALSE otherwise.
 */
function _xmlsitemap_update_cache($page = NULL) {
  global $user;
  $current_user = $user;
  $user = user_load(array('uid' => 0));
  $path = file_directory_path() .'/xmlsitemap';
  file_check_directory($path, FILE_CREATE_DIRECTORY);
  $node_count = db_result(db_query("SELECT COUNT(*) FROM {node}"));
  $dest = $path .'/sitemap.xml.gz';
  $link_count = _xmlsitemap_link_count();
  $chunk_size = variable_get('xmlsitemap_chunk_size', 50000);
  $status = TRUE;
  if ($link_count > $chunk_size) {
    $data = gzencode(_xmlsitemap_output_index($link_count));
    if (file_save_data($data, $dest, FILE_EXISTS_REPLACE) === 0 && ($page == 'index' || !isset($page))) {
      $status = FALSE;
    }
    for ($chunk = 0; $chunk < $link_count / $chunk_size; ++$chunk) {
      $dest = $path ."/sitemap$chunk.xml.gz";
      $data = gzencode(_xmlsitemap_output_chunk($chunk));
      if (file_save_data($data, $dest, FILE_EXISTS_REPLACE) === 0 && ($page == $chunk || !isset($page))) {
        $status = FALSE;
      }
    }
  }
  else {
    $chunk = 0;
    $data = gzencode(_xmlsitemap_output_chunk($chunk));
    if (file_save_data($data, $dest, FILE_EXISTS_REPLACE) === 0 && ($page == 'index' || !isset($page))) {
      $status = FALSE;
    }
  }
  variable_set('xmlsitemap_chunk_count', $chunk);
  variable_set('xmlsitemap_update', FALSE);
  if (!$status) {
    drupal_set_message(t('Unable to load site map. Make sure that there is an xmlsitemap directory in your files directory and that it is writable by Drupal.'), 'error');
  }
  $user = $current_user;
  return $status;
}

/**
 * Generate the site map index.
 * @param $link_count:
 * An integer containing the total number of links in the site
 * @return A string containing the site map index
 */
function _xmlsitemap_output_index($link_count) {
  $output = '';
  global $base_path;
  $xsl_path = file_directory_path() .'/xmlsitemap/gss.xsl';
  $xsl_path = file_exists($xsl_path) ? _xmlsitemap_file_create_url($xsl_path) : $base_path . drupal_get_path('module', 'xmlsitemap') .'/gss/gss.xsl';
  $output .= '<?xml version="1.0" encoding="UTF-8"?>'."\n";
  $output .= '<?xml-stylesheet type="text/xsl" href="'. $xsl_path .'" ?>'."\n";
  $output .= '<sitemapindex xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"'."\n";
  $output .= '              xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"'."\n";
  $output .= '              xsi:schemaLocation="http://www.sitemaps.org/schemas/sitemap/0.9'."\n";
  $output .= '                                  http://www.sitemaps.org/schemas/sitemap/0.9/siteindex.xsd">'."\n";
  $chunk_size = variable_get('xmlsitemap_chunk_size', 50000);
  for ($chunk = 0; $chunk < $link_count / $chunk_size; ++$chunk) {
    $output .= '<sitemap><loc>'. xmlsitemap_url("sitemap$chunk.xml", NULL, NULL, NULL, TRUE) .'</loc>';
    $previous = $chunk * $chunk_size;
    $links = array_slice(_xmlsitemap_links(), $previous, $chunk_size);
    $output .= '<lastmod>'. gmdate('Y-m-d\TH:i:s+00:00', array_reduce($links, '_xmlsitemap_chunk_last_change')) .'</lastmod>';
    $output .= "</sitemap>\n";
  }
  $output .= '</sitemapindex>';
  return $output;
}

/**
 * Compare link modification time to modification time of previous link.
 * @param $time:
 * Modification time of previous link
 * @param $value:
 * Link array
 * @return Most recent time
 */
function _xmlsitemap_chunk_last_change($time, $value) {
  if ($time < $value['#lastmod']) {
    $time = $value['#lastmod'];
  }
  return $time;
}

/**
 * Generate a chunk of the site map.
 * @param $chunk:
 * An integer specifying which chunk of the site map to display
 * @return A string containing a chunk of the site map
 */
function _xmlsitemap_output_chunk($chunk) {
  $output = '';
  global $base_path;
  if (!ini_get('safe_mode')) {
    set_time_limit(240);
  }
  $xsl_path = file_directory_path() .'/xmlsitemap/gss.xsl';
  $xsl_path = file_exists($xsl_path) ? _xmlsitemap_file_create_url($xsl_path) : $base_path . drupal_get_path('module', 'xmlsitemap') .'/gss/gss.xsl';
  $output .= '<?xml version="1.0" encoding="UTF-8"?>'."\n";
  $output .= '<?xml-stylesheet type="text/xsl" href="'. $xsl_path .'" ?>'."\n";
  $output .= '<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9"'."\n";
  $output .= '        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"'."\n";
  $output .= '        xsi:schemaLocation="http://www.sitemaps.org/schemas/sitemap/0.9'."\n";
  $output .= '                            http://www.sitemaps.org/schemas/sitemap/0.9/sitemap.xsd">'."\n";
  $chunk_size = variable_get('xmlsitemap_chunk_size', 50000);
  $previous = $chunk * $chunk_size;
  $output .= implode("\n", _xmlsitemap_format(array_slice(_xmlsitemap_links(), $previous, $chunk_size)));
  $output .= "\n</urlset>";
  return $output;
}

/**
 * Modified version of file_create_url(). Allows us to remove language
 * prefixes.
 * @param $path: the path to the file
 * @return A URL to the file
 */
function _xmlsitemap_file_create_url($path) {
  $path = trim(substr($path, strlen(file_directory_path())), '\\/');
  switch (variable_get('file_downloads', FILE_DOWNLOADS_PUBLIC)) {
    case FILE_DOWNLOADS_PUBLIC:
      return $GLOBALS['base_url'] .'/'. file_directory_path() .'/'. str_replace('\\', '/', $path);
    case FILE_DOWNLOADS_PRIVATE:
      return xmlsitemap_url('system/files/'. $path, NULL, NULL, NULL, TRUE);
  }
}

/**
 * Implementation of hook_file_download().
 */
function xmlsitemap_file_download($file) {
  if ($file == 'xmlsitemap/gss.xsl') {
    return array('Content-Type:');
  }
}

/**
 * Get all site map links.
 * @return An array of links from hook_xmlsitemap_links().
 */
function _xmlsitemap_links() {
  static $links;
  if (!isset($links)) {
    $entries = module_invoke_all('xmlsitemap_links');
    if (!empty($entries)) {
      foreach ($entries as $key => $link) {
        $lastmod[$key] = $link['#lastmod'];
      }
      array_multisort($lastmod, $entries);
    }
    $links = $entries;
  }
  return $links;
}

/**
 * Process an array of links.
 * @param $entries: An array of links to process
 * @return A string of formatted links
 */
function _xmlsitemap_format($entries) {
  $links = array();
  foreach ($entries as $entry) {
    if (isset($entry['#loc'])) {
      $link = '  <url>'."\n";
      $link .= '    <loc>'. check_url($entry['#loc']) .'</loc>'."\n";
      if (isset($entry['#lastmod'])) {
        $link .= '    <lastmod>'. gmdate('Y-m-d\TH:i:s+00:00', $entry['#lastmod']) .'</lastmod>'."\n";
      }
      if (isset($entry['#changefreq'])) {
        $link .= '    <changefreq>'. _xmlsitemap_frequency($entry['#changefreq']) .'</changefreq>'."\n";
      }
      if (isset($entry['#priority']) && $entry['#priority'] <= 1 && $entry['#priority'] >= 0) {
        $link .= '    <priority>'. number_format($entry['#priority'], 1) .'</priority>'."\n";
      }
      $link .= '  </url>';
      $links[] = $link;
    }
  }
  return $links;
}

/**
 * Determine the frequency of updates to a link.
 * @param $interval: The number of seconds since last change
 * @return A string representing the update frequency according to the
 * sitemaps.org protocol
 */
function _xmlsitemap_frequency($interval) {
  $frequencies = array(
    'always' => 3600,
    'hourly' => 86400,
    'daily' => 604800,
    'weekly' => 2419200,
    'monthly' => 29030400,
    'yearly' => 100000000,
    'never' => 0,
  );
  $frequency = 'never';
  if (array_key_exists($interval, $frequencies)) {
    $frequency = $interval;
  }
  elseif (is_numeric($interval)) {
    foreach ($frequencies as $frequency => $value) {
      if ($interval < $value) {
        break;
      }
    }
  }
  return $frequency;
}

/**
 * Implementation of hook_xmlsitemap_links().
 */
function xmlsitemap_xmlsitemap_links($type = NULL, $excludes = array()) {
  $links = array();
  if (!isset($type)) {
    global $base_url;
    $links[] = array('#loc' => "$base_url/", '#changefreq' => 'always', '#priority' => variable_get('xmlsitemap_front_page_priority', 1));
    $links = array_merge($links, _xmlsitemap_additional_links());
    $links = array_merge($links, module_invoke_all('gsitemap'));
    $links = array_merge($links, _xmlsitemap_xml_links());
    if (!empty($links)) {
      foreach ($links as $key => $link) {
        $loc[$key] = $link['#loc'];
      }
      array_multisort($loc, $links);
    }
  }
  return $links;
}

/**
 * Get additional links.
 * @return An array of links. Each link is an array containing the XML
 * values for a site map URL.
 */
function _xmlsitemap_additional_links() {
  $links = array();
  $result = db_query("
    SELECT xa.*, ua.dst AS alias FROM {xmlsitemap_additional} xa
    LEFT JOIN {url_alias} ua ON xa.pid = ua.pid
  ");
  while ($link = db_fetch_object($result)) {
    $age = time() - $link->last_changed;
    if (!empty($link->previously_changed)) {
      $interval = $link->last_changed - $link->previously_changed;
    }
    else {
      $interval = 0;
    }
    $links[] = array(
      '#loc' => xmlsitemap_url($link->path, $link->alias, NULL, NULL, TRUE),
      '#lastmod' => $link->last_changed,
      '#changefreq' => max($age, $interval),
      '#priority' => isset($link->priority) ? $link->priority : variable_get('xmlsitemap_additional_links_priority', 0.1),
    );
  }
  return $links;
}

/**
 * Extract links from site maps returned by hook_xmlsitemap_links().
 * @return An array of links.
 */
function _xmlsitemap_xml_links() {
  $links = array();
  $xml = module_invoke_all('xmlsitemap_links', 'xml');
  $xml = array_merge($xml, module_invoke_all('gsitemap', 'xml'));
  foreach ($xml as $entries) {
    $start = strpos($entries, '<url>');
    if ($start !== FALSE) {
      $length = strpos($entries, '</urlset>') - $start;
      $entries = substr($entries, $start, $length);
      $entries = explode('<url>', $entries);
      foreach ($entries as $value) {
        if (($start = strpos($value, '<loc>')) !== FALSE) {
          $length = $start + strlen('<loc>');
          $link['#loc'] = substr($value, $length, strpos($value, '</loc>') - $length);
          if (($start = strpos($value, '<lastmod>')) !== FALSE) {
            $length = $start + strlen('<lastmod>');
            $t = array_shift(explode('+', substr($value, $length, strpos($value, '</lastmod>') - $length)));
            $t = explode('T', $t);
            $t = array_merge(explode('-', $t[0]), explode(':', $t[1]));
            $link['#lastmod'] = gmmktime($t[3], $t[4], $t[5], $t[1], $t[2], $t[0]);
          }
          if (($start = strpos($value, '<changefreq>')) !== FALSE) {
            $length = $start + strlen('<changefreq>');
            $link['#changefreq'] = substr($value, $length, strpos($value, '</changefreq>') - $length);
          }
          if (($start = strpos($value, '<priority>')) !== FALSE) {
            $length = $start + strlen('<priority>');
            $link['#priority'] = substr($value, $length, strpos($value, '</priority>') - $length);
          }
          $links[] = $link;
        }
      }
    }
  }
  return $links;
}

/**
 * Modified version of url(). We don't want to do a separate database query
 * for each url, so we pass the alias as an extra parameter.
 * @param $alias: The URL alias. Default is NULL.
 * @return The fully formatted URL
 */
function xmlsitemap_url($path = NULL, $alias = NULL, $query = NULL, $fragment = NULL, $absolute = FALSE) {
  if (isset($fragment)) {
    $fragment = "#$fragment";
  }
  $colonpos = strpos($path, ':');
  if ($colonpos !== FALSE && !preg_match('![/?#]!', substr($path, 0, $colonpos)) && filter_xss_bad_protocol($path, FALSE) == check_plain($path)) {
    if (strpos($path, '#') !== FALSE) {
      list($path, $old_fragment) = explode('#', $path, 2);
      if (isset($old_fragment) && !isset($fragment)) {
        $fragment = "#$old_fragment";
      }
    }
    if (isset($query)) {
      $path .= (strpos($path, '?') !== FALSE ? '&' : '?') . $query;
    }
    return $path . $fragment;
  }
  global $base_url;
  static $script;
  static $clean_url;
  $script = isset($script) ? $script : strpos($_SERVER['SERVER_SOFTWARE'], 'Apache') === FALSE ? 'index.php' : '';
  $clean_url = isset($clean_url) ? $clean_url : variable_get('clean_url', FALSE);
  $base = ($absolute ? $base_url .'/' : base_path());

  if (!empty($path) && $path != '<front>') {
    $path = _xmlsitemap_get_path_alias($path, $alias);
    $path = drupal_urlencode($path);

    if (!$clean_url) {
      if (isset($query)) {
        return $base . $script .'?q='. $path .'&'. $query . $fragment;
      }
      else {
        return $base . $script .'?q='. $path . $fragment;
      }
    }
    else {
      if (isset($query)) {
        return $base . $path .'?'. $query . $fragment;
      }
      else {
        return $base . $path . $fragment;
      }
    }
  }
  else {
    if (isset($query)) {
      return $base . $script .'?'. $query . $fragment;
    }
    else {
      return $base . $fragment;
    }
  }
}

/**
 * Modified version of drupal_get_path_alias() for xmlsitemap_url().
 * @param $path: An internal Drupal path
 * @param $alias: The URL alias. Default is NULL.
 * @return A processed path
 */
function _xmlsitemap_get_path_alias($path, $alias = NULL) {
  $result = $path;
  if (!empty($alias)) {
    $result = $alias;
  }
  if (function_exists('custom_url_rewrite_outbound')) {
    custom_url_rewrite_outbound($result, $customarray = array('alias' => $alias), $path);
  }
  return $result;
}

/**
 * Implementation of hook_cron().
 */
function xmlsitemap_cron() {
  if (variable_get('xmlsitemap_cron_submit', FALSE) && variable_get('xmlsitemap_changed', FALSE)) {
    _xmlsitemap_ping();
  }
}

/**
 * Mark the site map as changed and the cache as needing update.
 * @return None
 */
function xmlsitemap_update_sitemap() {
  variable_set('xmlsitemap_changed', TRUE);
  variable_set('xmlsitemap_update', TRUE);
  if (variable_get('xmlsitemap_submit', FALSE)) {
    _xmlsitemap_submit_on_exit();
  }
}

/**
 * Schedule a call to _xmlsitemap_ping() to be run on exit. Use this
 * function instead of _xmlsitemap_ping() to avoid a delay in outputting
 * the page to the user.
 * @return TRUE if the function has been called previously, FALSE otherwise.
 */
function _xmlsitemap_submit_on_exit() {
  static $called = FALSE;
  $return = $called;
  $called = TRUE;
  return $return;
}

/**
 * Implementation of hook_exit().
 */
function xmlsitemap_exit() {
  if (_xmlsitemap_submit_on_exit()) {
    _xmlsitemap_ping();
  }
}

/**
 * Submit the site map to search engines.
 * @return None
 */
function _xmlsitemap_ping() {
  $status = _xmlsitemap_update_cache();
  if ($status) {
    module_invoke_all('xmlsitemap_engines', 'ping');
    variable_set('xmlsitemap_changed', FALSE);
  }
}
