modules/gsitemap/xmlsitemap.module

<?php
// $Id: xmlsitemap.module,v 1.19 2007/06/15 16:00:33 darrenoh Exp $

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

/**
 * Implementation of hook_help().
 */
function xmlsitemap_help($section) {
  switch ($section) {
    case 'admin/settings/xmlsitemap':
    case 'admin/settings/xmlsitemap/settings':
      return t('The following options allow you to alter the behavior of the XML Sitemap module. Your site map can be found at !url.', array('!url' => l(url('sitemap.xml', array('absolute' => TRUE)), 'sitemap.xml')));
  }
}

/**
 * Implementation of hook_perm().
 */
function xmlsitemap_perm() {
  return array('override node priority');
}

/**
 * Implementation of hook_menu().
 */
function xmlsitemap_menu() {
  $items = array();
  $items['admin/settings/xmlsitemap'] = array(
    'title' => 'XML Sitemap',
    'description' => 'Adjust the settings used to generate your XML site map.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('xmlsitemap_admin_settings'),
    'access arguments' => array('administer site configuration'),
  );
  $items['admin/settings/xmlsitemap/settings'] = array(
    'title' => 'Settings',
    'type' => MENU_DEFAULT_LOCAL_TASK,
  );
  $items['admin/settings/xmlsitemap/additional'] = array(
    'title' => 'Additional links',
    'description' => 'Specify additional pages to add to your site map.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('xmlsitemap_admin_settings_additional'),
    'weight' => 1,
    'type' => MENU_LOCAL_TASK,
  );
  $items['sitemap.xml'] = array(
    'title' => 'Site map index',
    'page callback' => 'xmlsitemap_output',
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
  );
  if ($verify = variable_get('xmlsitemap_verify', '')) {
    $items[$verify] = array(
      'title' => 'Google verification page',
      'page callback' => 'xmlsitemap_verify',
      'access arguments' => array('access content'),
      'type' => MENU_CALLBACK,
    );
  }
  for ($chunk = 0; $chunk < variable_get('xmlsitemap_chunk_count', 0); ++$chunk) {
    $items["sitemap$chunk.xml"] = array(
      'title' => 'Site map !number',
      'title arguments' => array('!number' => $chunk),
      'page callback' => 'xmlsitemap_output',
      'page arguments' => array("$chunk"),
      'access arguments' => array('access content'),
      'type' => MENU_CALLBACK,
    );
  }
  return $items;
}

/**
 * Menu callback; display verification page for Google.
 */
function xmlsitemap_verify() {
  echo 'Hello, Google!';
}

/**
 * Implementation of hook_form_alter().
 */
function xmlsitemap_form_alter(&$form, $form_id) {
  if (user_access('override node priority') && isset($form['type']) && $form_id == $form['type']['#value'] .'_node_form') {
    $node = $form['#node'];
    $form['xmlsitemap_settings'] = array(
      '#type' => 'fieldset',
      '#title' => t('XML Sitemap settings'),
      '#collapsible' => TRUE,
      '#collapsed' => TRUE,
      '#weight' => 30,
    );
    $form['xmlsitemap_settings']['priority_override'] = array(
      '#type' => 'textfield',
      '#title' => t('Priority override'),
      '#default_value' => $node->priority_override,
      '#size' => 10,
      '#maxlength' => 5,
      '#description' => t('Optionally override the site map priority for this post. The lowest priority is 0.0; the highest priority is 1.0. A priority of -1 will prevent this post from appearing in the site map.'),
    );
  }
}

/**
 * Implmentation of hook_nodeapi().
 */
function xmlsitemap_nodeapi(&$node, $op, $teaser = NULL, $page = NULL) {
  switch ($op) {
    case 'insert':
      if (!(strlen($node->priority_override) > 0 && is_numeric($node->priority_override) && user_access('override node priority'))) {
        $node->priority_override = 'NULL';
      }
      $pid = db_result(db_query("SELECT pid FROM {url_alias} WHERE src = '%s'", 'node/'. $node->nid));
      if ($pid === FALSE) {
        db_query("INSERT INTO {xmlsitemap} (nid, last_changed, priority_override) VALUES(%d, %d, %s)", $node->nid, $node->changed, $node->priority_override);
      }
      else {
        db_query("INSERT INTO {xmlsitemap} (nid, pid, last_changed, priority_override) VALUES (%d, %d, %d, %s)", $node->nid, $pid, $node->changed, $node->priority_override);
      }
      if (variable_get('xmlsitemap_submit', 0) && $node->status) {
        _xmlsitemap_submit_on_exit();
      }
      else {
        variable_set('xmlsitemap_changed', TRUE);
        variable_set('xmlsitemap_update', TRUE);
      }
      break;
    case 'prepare':
      if ($node->nid && user_access('override node priority')) {
        $result = db_query("SELECT priority_override FROM {xmlsitemap} WHERE nid = %d", $node->nid);
        if ($nd = db_result($result)) {
          $node->priority_override = $nd;
        }
      }
      break;
    case 'update':
      if (!(strlen($node->priority_override) > 0 && is_numeric($node->priority_override))) {
        $node->priority_override = 'NULL';
      }
      $pid = db_result(db_query("SELECT pid FROM {url_alias} WHERE src = '%s'", 'node/'. $node->nid));
      $result = db_query('SELECT * FROM {xmlsitemap} x LEFT JOIN {node} n USING (nid) WHERE x.nid = %d', $node->nid);
      if (!($oldnode = db_fetch_object($result))) {
        if ($pid === FALSE) {
          db_query('INSERT INTO {xmlsitemap} (nid, last_changed, priority_override) VALUES(%d, %d, %s)', $node->nid, $node->changed, $node->priority_override);
        }
        else {
          db_query('INSERT INTO {xmlsitemap} (nid, pid, last_changed, priority_override) VALUES (%d, %d, %d, %s)', $node->nid, $pid, $node->changed, $node->priority_override);
        }
      }
      else {
        if (user_access('override node priority')) {
          if ($pid === FALSE) {
            db_query('UPDATE {xmlsitemap} SET last_changed = %d, previously_changed = %d, priority_override = %s WHERE nid = %d', $node->changed, $oldnode->last_changed, $node->priority_override, $node->nid);
          }
          else {
            db_query('UPDATE {xmlsitemap} SET pid = %d, last_changed = %d, previously_changed = %s, priority_override = %s WHERE nid = %d', $pid, $node->changed, $oldnode->last_changed, $node->priority_override, $node->nid);
          }
        }
        else {
          if ($pid === FALSE) {
            db_query('UPDATE {xmlsitemap} SET last_changed = %d, previously_changed = %d WHERE nid = %d', $node->changed, $oldnode->last_changed, $node->nid);
          }
          else {
            db_query("UPDATE {xmlsitemap} SET pid = %d, last_changed = %d, previously_changed = %s WHERE nid = %d", $pid, $node->changed, $oldnode->last_changed, $node->nid);
          }
        }
      }
      if (variable_get('xmlsitemap_submit', 0) && ($node->status || $oldnode->status)) {
        _xmlsitemap_submit_on_exit();
      }
      else {
        variable_set('xmlsitemap_changed', TRUE);
        variable_set('xmlsitemap_update', TRUE);
      }
      break;
    case 'delete':
      db_query('DELETE FROM {xmlsitemap} WHERE nid = %d', $node->nid);
      if (variable_get('xmlsitemap_submit', 0) && $node->status) {
        _xmlsitemap_submit_on_exit();
      }
      else {
        variable_set('xmlsitemap_changed', TRUE);
        variable_set('xmlsitemap_update', TRUE);
      }
      break;
    case 'validate':
      if (strlen($node->priority_override) > 0) {
        if (!is_numeric($node->priority_override) || (($node->priority_override > 1) || ($node->priority_override < 0 && $node->priority_override != -1))) {
          form_set_error('priority_override', t('Priority must be a number between 0.0 and 1.0, inclusive, or -1 to prevent this node from appearing in the site map.'));
        }
      }
      break;
  }
}

/**
 * Implementation of hook_comment().
 */
function xmlsitemap_comment($op, $comment) {
  $comment = (object) $comment;
  if ($op == 'insert' || $op == 'update' || $op == 'moderate' || $op == 'delete') {
    $result = db_query('SELECT * FROM {xmlsitemap} WHERE nid = %d', $comment->nid);
    if (!($node = db_fetch_object($result))) {
      $node = db_fetch_object(db_query('SELECT nid, changed FROM {node} WHERE nid = %d', $comment->nid));
      db_query('INSERT INTO {xmlsitemap} (nid, last_changed, last_comment) VALUES (%d, %d, %d)', $node->nid, $node->changed, $comment->timestamp);
    }
    else {
      if (isset($node->last_comment)) {
        db_query('UPDATE {xmlsitemap} SET last_comment = %d, previous_comment = %d WHERE nid = %d', $comment->timestamp, $node->last_comment, $node->nid);
      }
      else {
        db_query('UPDATE {xmlsitemap} SET last_comment = %d WHERE nid = %d', $comment->timestamp, $node->nid);
      }
    }
    if (variable_get('xmlsitemap_submit', 0)) {
      _xmlsitemap_submit_on_exit();
    }
    else {
      variable_set('xmlsitemap_changed', TRUE);
      variable_set('xmlsitemap_update', TRUE);
    }
  }
}

/**
 * Menu callback; return module settings form.
 */
function xmlsitemap_admin_settings() {
  $form['priority_settings'] = array(
    '#type' => 'fieldset',
    '#title' => t('Priority settings'),
    '#collapsible' => TRUE,
  );
  $form['priority_settings']['xmlsitemap_frontpage'] = array(
    '#type' => 'textfield',
    '#title' => t('Front page priority'),
    '#default_value' => variable_get('xmlsitemap_frontpage', '1.0'),
    '#size' => 10,
    '#maxlength' => 5,
    '#description' => t('This is the absolute priority for the front page. Values can range between 0.0 and 1.0.'),
  );
  $form['priority_settings']['xmlsitemap_promotewt'] = array(
    '#type' => 'textfield',
    '#title' => t('Promotion adjustment'),
    '#default_value' => variable_get('xmlsitemap_promotewt', '0.3'),
    '#size' => 10,
    '#maxlength' => 5,
    '#description' => t('This number will be added to the priority of each node that is promoted to the front page.'),
  );
  $form['priority_settings']['xmlsitemap_commentwt'] = array(
    '#type' => 'textfield',
    '#title' => t('Comment ratio weight'),
    '#default_value' => variable_get('xmlsitemap_commentwt', '0.5'),
    '#size' => 10,
    '#maxlength' => 5,
    '#description' => t('This number will be multiplied with the ratio of the number of comments on the node over the number of comments on the node with the most comments, i.e., this number will be added to the priority of the node with the most comments.'),
  );
  $form['priority_settings'][] = array(
    '#value' => '<p>'. t('You can enter -1 in any of the following fields to prevent nodes of that type from appearing in the site map.') .'</p>',
  );
  foreach (node_get_types('names') as $type => $name) {
    $form['priority_settings']['xmlsitemap_'. $type .'wt'] =  array(
      '#type' => 'textfield',
      '#title' => t('%name adjustment', array('%name' => ucfirst($name))),
      '#default_value' => variable_get('xmlsitemap_'. $type .'wt', '0.1'),
      '#size' => 10,
      '#maxlength' => 5,
      '#description' => t('This number will be added to the priority of nodes of type %name.', array('%name' => $name)),
    );
  }

  $form['search_engines'] = array(
    '#type' => 'fieldset',
    '#title' => t('Search engines'),
    '#collapsible' => TRUE,
    '#collapsed' => TRUE,
  );
  $form['search_engines']['google'] = array(
    '#type' => 'fieldset',
    '#title' => t('Google'),
  );
  $form['search_engines']['google']['xmlsitemap_google_submit'] = array(
    '#type' => 'checkbox',
    '#title' => t('Submit site map to Google.'),
    '#default_value' => variable_get('xmlsitemap_google_submit', TRUE),
  );
  $form['search_engines']['google']['xmlsitemap_google_url'] = array(
    '#type' => 'textfield',
    '#title' => t('Submission URL'),
    '#default_value' => variable_get('xmlsitemap_google_url', 'http://www.google.com/webmasters/tools/ping?sitemap='. url('sitemap.xml', array('absolute' => TRUE))),
    '#description' => t('The URL to submit the site map to.'),
  );
  $form['search_engines']['google']['xmlsitemap_verify'] = array(
    '#type' => 'textfield',
    '#title' => t('Verification link'),
    '#default_value' => variable_get('xmlsitemap_verify', ''),
    '#description' => t('In order to show statistics, Google will ask you to verify that you control this site by creating a page with a certain name. Enter that name here and the XML Sitemap module will hook that filename. Note that this will only work if you have clean URLs enabled.'),
  );
  $form['search_engines']['yahoo'] = array(
    '#type' => 'fieldset',
    '#title' => t('Yahoo'),
  );
  $form['search_engines']['yahoo']['xmlsitemap_yahoo_submit'] = array(
    '#type' => 'checkbox',
    '#title' => t('Submit site map to Yahoo.'),
    '#default_value' => variable_get('xmlsitemap_yahoo_submit', FALSE),
  );
  $form['search_engines']['yahoo']['xmlsitemap_yahoo_url'] = array(
    '#type' => 'textfield',
    '#title' => t('Submission URL'),
    '#default_value' => variable_get('xmlsitemap_yahoo_url', 'http://search.yahooapis.com/SiteExplorerService/V1/ping?sitemap='. url('sitemap.xml', array('absolute' => TRUE))),
    '#description' => t('The URL to submit the site map to.'),
  );
  $form['search_engines']['ask.com'] = array(
    '#type' => 'fieldset',
    '#title' => t('Ask.com'),
  );
  $form['search_engines']['ask.com']['xmlsitemap_ask_com_submit'] = array(
    '#type' => 'checkbox',
    '#title' => t('Submit site map to Ask.com.'),
    '#default_value' => variable_get('xmlsitemap_ask_com_submit', FALSE),
  );
  $form['search_engines']['ask.com']['xmlsitemap_ask_com_url'] = array(
    '#type' => 'textfield',
    '#title' => t('Submission URL'),
    '#default_value' => variable_get('xmlsitemap_ask_com_url', 'http://submissions.ask.com/ping?sitemap='. url('sitemap.xml', array('absolute' => TRUE))),
    '#description' => t('The URL to submit the site map to.'),
  );
  $form['search_engines']['xmlsitemap_submit'] = array(
    '#type' => 'checkbox',
    '#title' => t('Submit site map when updated.'),
    '#default_value' => variable_get('xmlsitemap_submit', 0),
    '#description' => t('If enabled, search engines will be notified of changes to the site map each time it is updated.'),
  );
  $form['search_engines']['xmlsitemap_cron_submit'] = array(
    '#type' => 'checkbox',
    '#title' => t('Submit site map on cron run.'),
    '#default_value' => variable_get('xmlsitemap_cron_submit', 0),
    '#description' => t('If enabled, search engines will be notified of changes to the site map each time cron is run.'),
  );
  $form['search_engines']['xmlsitemap_logacc'] = array(
    '#type' => 'checkbox',
    '#title' => t('Log accesses.'),
    '#default_value' => variable_get('xmlsitemap_logacc', 0),
    '#description' => t('If enabled, a watchdog entry will be made each time the site map is accessed, containing information about the requestor.'),
  );

  $form['other_settings'] = array(
    '#type' => 'fieldset',
    '#title' => t('Other settings'),
    '#collapsible' => TRUE,
    '#collapsed' => TRUE,
  );
  $form['other_settings']['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 send at one time. Values can range between 1 and 50,000.'),
  );
  $form['other_settings']['xmlsitemap_countcom'] = array(
    '#type' => 'checkbox',
    '#title' => t('Count comments in change date and frequency'),
    '#default_value' => variable_get('xmlsitemap_countcom', 1),
    '#description' => t('If enabled, the frequency of comments on a node will affect its change frequency and last modification date.'),
  );
  $form['other_settings']['xmlsitemap_showterms'] = array(
    '#type' => 'checkbox',
    '#title' => t('Include links to taxonomy term pages'),
    '#default_value' => variable_get('xmlsitemap_showterms', 0),
    '#description' => t('If enabled, links to taxonomy term pages will be included in the site map.'),
  );
  $form['other_settings']['xmlsitemap_showusers'] = array(
    '#type' => 'checkbox',
    '#title' => t('Include links to user profile pages'),
    '#default_value' => variable_get('xmlsitemap_showusers', 0),
    '#description' => t('If enabled, links to user profile pages will be included in the site map (requires anonymous users to have "access user profiles" permission).'),
  );

  menu_rebuild(); // Needed for Google verification link

  return system_settings_form($form);
}

function xmlsitemap_admin_settings_validate($form_id, $form_values) {
  if ($form_values['xmlsitemap_chunk_size'] > 50000) {
    form_set_error('xmlsitemap_chunk_size', t('Cannot send more than 50,000 links at one time.'));
  }
  else {
    variable_set('xmlsitemap_changed', TRUE);
    variable_set('xmlsitemap_update', TRUE);
  }
}

/**
 * Menu callback; return additional links form.
 */
function xmlsitemap_admin_settings_additional() {
  $pages = array();
  $result = db_query('SELECT path FROM {xmlsitemap_additional}');
  while ($page = db_fetch_object($result)) {
    $pages[] = $page->path;
  }
  $pages = implode("\n", $pages);
  $form['old_pages'] = array(
    '#type' => 'hidden',
    '#value' => $pages,
  );
  $form['pages'] = array(
    '#type' => 'textarea',
    '#title' => t('Pages'),
    '#default_value' => $pages,
    '#description' => t('Enter one page per line as Drupal paths. For example, if the URL is <em>http://example.com/node/1</em>, enter <em>node/1</em>.'),
    '#cols' => 30,
    '#rows' => 15,
  );
  $form['priority'] = array(
    '#type' => 'textfield',
    '#title' => t('Additional links priority'),
    '#default_value' => variable_get('xmlsitemap_priority', '0.5'),
    '#size' => 10,
    '#maxlength' => 5,
    '#description' => t('This is the absolute priority for additional links. Values can range between 0.0 and 1.0. The default priority is 0.5.'),
  );
  return system_settings_form($form);
}

function xmlsitemap_admin_settings_additional_validate($form_id, $form_values) {
  if ($form_values['priority'] > 1 || $form_values['priority'] < 0) {
    form_set_error('priority', t('Priority must be between 0.0 and 1.0.'));
  }
}

function xmlsitemap_admin_settings_additional_submit($form_id, $form_values) {
  if ($form_values['priority'] == '') {
    $form_values['priority'] = '0.5';
  }
  else {
    $form_values['priority'] = number_format($form_values['priority'], 1);
  }
  $old_pages = explode("\n", $form_values['old_pages']);
  $pages = explode("\n", $form_values['pages']);
  foreach ($pages as $key => $page) {
    $pages[$key] = trim($page);
  }
  $delete_pages = array_diff($old_pages, $pages);
  foreach ($delete_pages as $page) {
    if (!empty($page)) {
      db_query("DELETE FROM {xmlsitemap_additional} WHERE path = '%s'", $page);
      variable_set('xmlsitemap_changed', TRUE);
      variable_set('xmlsitemap_update', TRUE);
    }
  }
  $add_pages = array_diff($pages, $old_pages);
  foreach ($add_pages as $page) {
    $page = trim($page);
    $pid = db_result(db_query("SELECT pid FROM {url_alias} WHERE src = '%s'", $page));
    if (!empty($page)) {
      if ($pid === FALSE) {
        db_query("
          INSERT INTO {xmlsitemap_additional} (path, last_changed, previously_changed)
          VALUES ('%s', %d, %d)
        ", $page, time(), NULL);
      }
      else {
        db_query("
          INSERT INTO {xmlsitemap_additional} (path, pid, last_changed, previously_changed)
          VALUES ('%s', %d, %d, %d)
        ", $page, $pid, time(), NULL);
      }
      variable_set('xmlsitemap_changed', TRUE);
      variable_set('xmlsitemap_update', TRUE);
    }
  }
  db_query('UPDATE {xmlsitemap_additional} SET priority = %s', $form_values['priority']);
  variable_set('xmlsitemap_priority', $form_values['priority']);
}

/**
 * Implementation of hook_xmlsitemap().
 */
function xmlsitemap_xmlsitemap($type = NULL, $excludes = array()) {
  $additional = array();
  switch ($type) {
    case 'node':
    case 'term':
    case 'user':
      break;
    default:
      $result = db_query('SELECT x.*, u.dst AS alias FROM {xmlsitemap_additional} x LEFT JOIN {url_alias} u ON x.pid = u.pid');
      while ($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;
        }
        $entry = array(
          '#loc' => xmlsitemap_url($link->path, $link->alias, array('absolute' => TRUE)),
          '#lastmod' => $link->last_changed,
          '#changefreq' => max($age, $interval),
          '#priority' => $link->priority,
        );
        $additional[] = $entry;
      }
  }
  return $additional;
}

/**
 * Implementation of hook_cron().
 */
function xmlsitemap_cron() {
  if (variable_get('xmlsitemap_cron_submit', 0) && variable_get('xmlsitemap_changed', FALSE)) {
    _xmlsitemap_submit();
  }
}

/**
 * Menu callback; display the site map.
 * @param $chunk: An integer specifying which chunk of the site map is being
 *        requested. If not set, display the site map index.
 * @return Nothing
 */
function xmlsitemap_output($chunk = NULL) {
  drupal_set_header('Content-type: text/xml; charset=utf-8');
  global $base_path;
  $path = file_directory_temp();
  $directories = 'drupal_xmlsitemap/'. getenv('HTTP_HOST') . $base_path;
  $directories = explode('/', trim($directories, '/'));
  foreach ($directories as $directory) {
    $path = "$path/". str_replace('~', '_', $directory);
  }
  if (isset($chunk)) {
    $dest = "$path/$chunk.xml.gz";
    $type = t('Site map @chunk', array('@chunk' => $chunk));
  }
  else {
    $dest = "$path/index.xml.gz";
    $type = t('Site map index');
  }
  $status = TRUE;
  if (!file_exists($dest) || variable_get('xmlsitemap_update', FALSE)) {
    $status = _xmlsitemap_update_cache();
  }
  if ($status) {
    if (strpos(getenv('HTTP_ACCEPT_ENCODING'), 'gzip') === FALSE) {
      readgzfile($dest);
    }
    else {
      drupal_set_header('Content-Encoding: gzip');
      readfile($dest);
    }
    if (variable_get('xmlsitemap_logacc', 0)) {
      if (strpos(getenv('HTTP_USER_AGENT'), 'Googlebot') === FALSE) {
        watchdog('xmlsitemap', t('!sitemap downloaded by @user-agent at @address.', array('!sitemap' => $type, '@user-agent' => getenv('HTTP_USER_AGENT'), '@address' => getenv('REMOTE_ADDR'))));
      }
      else {
        watchdog('xmlsitemap', t('!sitemap downloaded by Google.', array('!sitemap' => $type)));
      }
    }
  }
  else {
    drupal_set_message(t('Unable to load site map. Make sure your temporary directory exists and is writable by Drupal.'), 'error');
  }
}

/**
 * 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_url;
  $countcom = variable_get('xmlsitemap_countcom', 1);

  $output .= '<?xml version="1.0" encoding="UTF-8"?>'."\n";
  $output .= '<?xml-stylesheet type="text/xsl" href="'. $base_url .'/'. drupal_get_path('module', 'xmlsitemap') .'/gss.xsl" ?>'."\n";
  $output .= '<sitemapindex xmlns="http://www.sitemaps.org/schemas/sitemap/0.9" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.sitemaps.org/schemas/sitemap/0.9 http://www.sitemaps.org/schemas/sitemap/0.9/siteindex.xsd">'."\n";

  $excludes = array();
  foreach (node_get_types() as $type => $name) {
    if (variable_get('xmlsitemap_'. $type .'wt', 0) < 0) {
      $excludes[] = db_escape_string($type);
    }
  }

  $chunk_size = variable_get('xmlsitemap_chunk_size', 50000);
  for ($chunk = 0; $chunk < $link_count / $chunk_size; ++$chunk) {
    $output .= '<sitemap><loc>'. url("sitemap$chunk.xml", array('absolute' => TRUE)) .'</loc>';

    $range->low = $chunk * $chunk_size;
    $range->high = ($chunk + 1) * $chunk_size;
    $last_changed_node = db_result(db_query("SELECT MAX(changed) as changed from {node} WHERE nid >= %d AND nid < %d", $range->low, $range->high));

    if ($countcom) {
      $last_changed_comment = db_result(db_query("SELECT MAX(timestamp) as timestamp from {comments} WHERE nid >= %d AND nid < %d", $range->low, $range->high));
    }
    else {
      $last_changed_comment = 0;
    }

    $output .= '<lastmod>'. gmdate('Y-m-d\TH:i:s+00:00', max($last_changed_node, $last_changed_comment)) .'</lastmod>';
    $output .= "</sitemap>\n";
  }
  $output .= '</sitemapindex>';
  return $output;
}

/**
 * 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_url;
  if (!ini_get('safe_mode')) {
    set_time_limit(240);
  }
  $range->low = $chunk * variable_get('xmlsitemap_chunk_size', 50000);
  $range->high = $range->low + variable_get('xmlsitemap_chunk_size', 50000);

  $output .= '<?xml version="1.0" encoding="UTF-8"?>'."\n";
  $output .= '<?xml-stylesheet type="text/xsl" href="'. $base_url .'/'. drupal_get_path('module', 'xmlsitemap') .'/gss.xsl" ?>'."\n";
  $output .= '<urlset xmlns="http://www.sitemaps.org/schemas/sitemap/0.9" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.sitemaps.org/schemas/sitemap/0.9 http://www.sitemaps.org/schemas/sitemap/0.9/sitemap.xsd">'."\n";

  if ($range->low < $range->high) {
    $previous_links = 1;
    if ($previous_links >= $range->low) {
      $output .= "<url><loc>$base_url/</loc><changefreq>always</changefreq><priority>". number_format(variable_get('xmlsitemap_frontpage', '1.0'), 1) ."</priority></url>\n";
      $range->low = $previous_links;
    }
  }
  if ($range->low < $range->high) {
    $excludes = array();
    foreach (node_get_types() as $type => $name) {
      if (variable_get('xmlsitemap_'. $type .'wt', 0) < 0) {
        $excludes[$type] = db_escape_string($type);
      }
    }
    $additional = module_invoke_all('xmlsitemap', 'node', $excludes);
    if (!empty($additional)) {
      $output .= _xmlsitemap_sublinks($additional, 'node', 'nid', $range, $previous_links, $excludes);
    }
    else {
      $count = db_result(db_query(db_rewrite_sql("
        SELECT COUNT(*)
        FROM {node} n
        LEFT JOIN {xmlsitemap} x
        ON n.nid = x.nid
        WHERE n.status > 0
        AND (x.priority_override >= 0 OR x.priority_override IS NULL)
        AND n.type NOT IN ('". implode("', '", $excludes) ."')
      ")));
      $count = $count + $previous_links > $range->high ? $range->high - $previous_links : $count;
      $previous_links = $previous_links + $count;
      if ($previous_links >= $range->low && !empty($count)) {
        $nid = db_result(db_query_range(db_rewrite_sql("
          SELECT n.nid
          FROM {node} n
          LEFT JOIN {xmlsitemap} x
          ON n.nid = x.nid
          WHERE n.status > 0
          AND (x.priority_override >= 0 OR x.priority_override IS NULL)
          AND n.type NOT IN ('". implode("', '", $excludes) ."')
          ORDER BY n.nid
        "), $count - 1, 1));
        $limit = $previous_links - $range->low;
        $output .= _xmlsitemap_links('nid', $nid, $limit, $excludes);
        $range->low = $previous_links;
      }
    }
  }
  if ($range->low < $range->high && variable_get('xmlsitemap_showterms', FALSE)) {
    $additional = module_invoke_all('xmlsitemap', 'term');
    if (!empty($additional)) {
      $output .= _xmlsitemap_sublinks($additional, 'term_data', 'tid', $range, $previous_links);
    }
    else {
      $count = db_result(db_query(db_rewrite_sql('SELECT COUNT(*) FROM {term_data}', 'term_data', 'tid')));
      $count = $count > $range->high - $previous_links ? $range->high - $previous_links : $count;
      $previous_links = $previous_links + $count;
      if ($previous_links >= $range->low && !empty($count)) {
        $tid = db_result(db_query_range(db_rewrite_sql('SELECT tid FROM {term_data} ORDER BY tid', 'term_data', 'tid'), $count - 1, 1));
        $limit = $previous_links - $range->low;
        $output .= _xmlsitemap_links('tid', $tid, $limit);
        $range->low = $previous_links;
      }
    }
  }
  if ($range->low < $range->high && variable_get('xmlsitemap_showusers', FALSE) && user_access('access user profiles')) {
    $additional = module_invoke_all('xmlsitemap', 'user');
    if (!empty($additional)) {
      $output .= _xmlsitemap_sublinks($additional, 'users', 'uid', $range, $previous_links);
    }
    else {
      $count = db_result(db_query('SELECT COUNT(*) FROM {users}'));
      $count = $count > $range->high - $previous_links ? $range->high - $previous_links : $count;
      $previous_links = $previous_links + $count;
      if ($previous_links >= $range->low && !empty($count)) {
        $uid = db_result(db_query_range('SELECT uid FROM {users} ORDER BY uid', $count - 1, 1));
        $limit = $previous_links - $range->low;
        $output .= _xmlsitemap_links('uid', $uid, $limit);
        $range->low = $previous_links;
      }
    }
  }
  if ($range->low < $range->high) {
    $additional = _xmlsitemap_xml();
    if (!empty($additional)) {
      $link = $range->low - $previous_links;
      $count = count($additional);
      $count = $count > $range->high - $previous_links ? $range->high - $previous_links : $count;
      $previous_links = $previous_links + $count;
      if ($previous_links >= $range->low) {
        $limit = $previous_links - $range->low;
        foreach (array_slice($additional, $link, $limit) as $entry) {
          $output .= $entry;
        }
        $range->low = $previous_links;
      }
    }
  }
  if ($range->low < $range->high) {
    $additional = module_invoke_all('xmlsitemap');
    if (!empty($additional)) {
      $link = $range->low - $previous_links;
      $count = count($additional);
      $count = $count > $range->high - $previous_links ? $range->high - $previous_links : $count;
      $previous_links = $previous_links + $count;
      if ($previous_links >= $range->low) {
        $limit = $previous_links - $range->low;
        $output .= _xmlsitemap_additional(array_slice($additional, $link, $limit));
        $range->low = $previous_links;
      }
    }
  }
  $output .= '</urlset>';
  return $output;
}

/**
 * Return formatted links and sub-links.
 * @param $additional: An array of links
 * @param $table: A string specifying the table to retrieve links from
 * @param $type: A string specifying the type of links to retrieve
 * @param $range: An object containing low (first link in range) and high
 *        (first link in next range) counts.
 * @param $previous_links: An integer containing the number of links already
 *        printed
 * @return A string of formatted links
 */
function _xmlsitemap_sublinks($additional, $table, $type, &$range, &$previous_links, $excludes = array()) {
  $output = '';
  foreach ($additional as $key => $entry) {
    $link_count[$key] = $entry[$type];
  }
  $link_count = array_count_values($link_count);
  $previous_id = 0;
  $link = 0;
  foreach ($link_count as $id => $links) {
    if ($range->low < $range->high) {
      if ($type == 'nid') {
        $count = db_result(db_query(db_rewrite_sql("
          SELECT COUNT(*)
          FROM {node} n
          LEFT JOIN {xmlsitemap} x
          ON n.nid = x.nid
          WHERE n.status > 0
          AND (x.priority_override >= 0 OR x.priority_override IS NULL)
          AND n.type NOT IN ('". implode("', '", $excludes) ."')
          AND n.nid >= %d
          AND n.nid <= %d
        "), $previous_id, $id));
      }
      elseif ($type == 'uid') {
        $count = db_result(db_query('SELECT COUNT(*) FROM {users} WHERE uid >= %d AND uid <= %d'), $previous_id, $id);
      }
      else {
        $count = db_result(db_query(db_rewrite_sql('SELECT COUNT(*) FROM {%s} WHERE %s >= %d AND %s <= %d', $table, $type), $table, $type, $previous_id, $type, $id));
      }
      $previous_id = $id + 1;
      $count = $count + $previous_links > $range->high ? $range->high - $previous_links : $count;
      $previous_links = $previous_links + $count;
      if ($previous_links >= $range->low) {
        $limit = $previous_links - $range->low;
        $output .= _xmlsitemap_links($type, $id, $limit, $excludes);
        $range->low = $previous_links;
      }
    }
    else {
      break;
    }
    if ($range->low < $range->high) {
      $links = $links + $previous_links > $range->high ? $range->high - $previous_links : $links;
      $previous_links = $previous_links + $links;
      if ($previous_links >= $range->low) {
        $limit = $previous_links - $range->low;
        $output .= _xmlsitemap_additional(array_slice($additional, $link, $limit));
        $range->low = $previous_links;
      }
      $link = $link + $links;
    }
    else {
      break;
    }
  }
  if ($range->low < $range->high) {
    if ($type == 'nid') {
      $count = db_result(db_query(db_rewrite_sql("
        SELECT COUNT(*)
        FROM {node} n
        LEFT JOIN {xmlsitemap} x
        ON n.nid = x.nid
        WHERE n.status > 0
        AND (x.priority_override >= 0 OR x.priority_override IS NULL)
        AND n.type NOT IN ('". implode("', '", $excludes) ."')
        AND n.nid >= %d
      "), $previous_id));
      $count = $count + $previous_links > $range->high ? $range->high - $previous_links : $count;
      $id = db_result(db_query_range(db_rewrite_sql("
        SELECT n.nid
        FROM {node} n
        LEFT JOIN {xmlsitemap} x
        ON n.nid = x.nid
        WHERE n.status > 0
        AND (x.priority_override >= 0 OR x.priority_override IS NULL)
        AND n.type NOT IN ('". implode("', '", $excludes) ."')
        AND n.nid >= %d
        ORDER BY n.nid
      "), $previous_id, $count - 1, 1));
    }
    elseif ($type == 'uid') {
      $count = db_result(db_query('SELECT COUNT(*) FROM {users} WHERE uid >= %d'), $previous_id);
      $count = $count + $previous_links > $range->high ? $range->high - $previous_links : $count;
      $id = db_result(db_query_range('SELECT uid FROM {users} WHERE uid >= %d ORDER BY uid', $count - 1, 1), $previous_id);
    }
    else {
      $count = db_result(db_query(db_rewrite_sql('SELECT COUNT(*) FROM {%s} WHERE %s >= %d', $table, $type), $table, $type, $previous_id));
      $count = $count + $previous_links > $range->high ? $range->high - $previous_links : $count;
      $id = db_result(db_query_range(db_rewrite_sql('SELECT %s FROM {%s} WHERE %s >= %d ORDER BY %s', $table, $type), $type, $table, $type, $previous_id, $type, $count - 1, 1));
    }
    $previous_links = $previous_links + $count;
    if ($previous_links >= $range->low) {
      $limit = $previous_links < $range->high ? $previous_links - $range->low : $range->high - $range->low;
      $output .= _xmlsitemap_links($type, $id, $limit, $excludes);
      $range->low = $previous_links;
    }
  }
  return $output;
}

/**
 * Return formatted links.
 * @param $type A string specifying the type of links to return
 * @param $id The id of the last link to return
 * @param $limit An integer containing the number of links to return
 * @return A string of formatted links
 */
function _xmlsitemap_links($type, $id, $limit, $excludes = array()) {
  $output = '';
  switch ($type) {
    case 'tid':
      $offset = db_result(db_query(db_rewrite_sql('SELECT COUNT(*) - %d FROM {term_data} WHERE tid <= %d', 'term_data', 'tid'), $limit, $id));
      $result = db_query_range(db_rewrite_sql('SELECT * FROM {term_data} WHERE tid <= %d ORDER BY tid', 'term_data', 'tid'), $id, $offset, $limit);
      while ($term = db_fetch_object($result)) {
        $output .= '<url><loc>'. url(taxonomy_term_path($term), array('absolute' => TRUE)) ."</loc><changefreq>always</changefreq></url>\n";
      }
      break;
    case 'uid':
      $offset = db_result(db_query('SELECT COUNT(*) - %d FROM {users} WHERE uid <= %d', $limit, $id));
      $result = db_query_range('SELECT uid FROM {users} WHERE uid <= %d ORDER BY uid', $id, $offset, $limit);
      while ($user = db_fetch_object($result)) {
        $output .= '<url><loc>'. url('user/'. $user->uid, array('absolute' => TRUE)) ."</loc><changefreq>always</changefreq></url>\n";
      }
      break;
    case 'nid':
      $countcom = variable_get('xmlsitemap_countcom', 1);
      $offset = db_result(db_query(db_rewrite_sql("
        SELECT COUNT(*) - %d
        FROM {node} n
        LEFT JOIN {xmlsitemap} x
        ON n.nid = x.nid
        WHERE n.status > 0
        AND (x.priority_override >= 0 OR x.priority_override IS NULL)
        AND n.type NOT IN ('". implode("', '", $excludes) ."')
        AND n.nid <= %d
      "), $limit, $id));
      if (module_exists('comment')) {
        $result = db_query_range(db_rewrite_sql("
          SELECT n.nid, n.type, n.promote, s.comment_count, n.changed, x.previously_changed, s.last_comment_timestamp, x.previous_comment, x.priority_override, u.dst AS alias
          FROM {node} n
          LEFT JOIN {node_comment_statistics} s
          ON n.nid = s.nid
          LEFT JOIN {xmlsitemap} x
          ON n.nid = x.nid
          LEFT JOIN {url_alias} u
          ON x.pid = u.pid
          WHERE n.status > 0
          AND (x.priority_override >= 0 OR x.priority_override IS NULL)
          AND n.type NOT IN ('". implode("', '", $excludes) ."')
          AND n.nid <= %d
          ORDER BY n.nid
        "), $id, $offset, $limit);
        $maxcomments = db_result(db_query('SELECT MAX(comment_count) FROM {node_comment_statistics}'));
      }
      else {
        $result = db_query_range(db_rewrite_sql("
          SELECT n.nid, n.type, n.promote, n.changed, x.previously_changed, x.priority_override, u.dst AS alias
          FROM {node} n
          LEFT JOIN {xmlsitemap} x
          ON n.nid = x.nid
          LEFT JOIN {url_alias} u
          ON x.pid = u.pid
          WHERE n.status > 0
          AND (x.priority_override >= 0 OR x.priority_override IS NULL)
          AND n.type NOT IN ('". implode("', '", $excludes) ."')
          AND n.nid <= %d
          ORDER BY n.nid
        "), $id, $offset, $limit);
        $maxcomments = 0;
      }
      while ($node = db_fetch_object($result)) {
        $pri = xmlsitemap_node_priority($node, $maxcomments);
        if ($pri < 0) {
          continue;
        }
        $output .= '<url><loc>'. xmlsitemap_url('node/'. $node->nid, $node->alias, array('absolute' => TRUE)) .'</loc>';
        $output .= '<lastmod>'. gmdate('Y-m-d\TH:i:s+00:00', max($node->changed, $node->last_comment_timestamp * $countcom)) .'</lastmod>';
        $output .= '<priority>'. number_format($pri, 1) .'</priority>';
        $age = time() - max($node->changed, $node->last_comment_timestamp * $countcom);
        if ($countcom) {
          if (!empty($node->previously_changed) && isset($node->previous_comment)) {
            $interval = min($node->changed, $node->last_comment_timestamp) - max($node->previously_changed, $node->previous_comment);
          }
          elseif (!empty($node->previously_changed)) {
            $interval = min($node->changed, $node->last_comment_timestamp) - $node->previously_changed;
          }
          elseif (isset($node->previous_comment)) {
            $interval = min($node->changed, $node->last_comment_timestamp) - $node->previous_comment;
          }
          else {
            $interval = 0;
          }
        }
        else {
          if (!empty($node->previously_changed)) {
            $interval = $node->changed - $node->previously_changed;
          }
          else {
            $interval = 0;
          }
        }
        $output .= '<changefreq>'. _xmlsitemap_frequency(max($age, $interval)) ."</changefreq></url>\n";
      }
      break;
  }
  return $output;
}

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

/**
 * Calculate the priority of a node.
 * @param $node: A node object
 * @param $maxcomments: The maximum number of comments for any node, used to
 *        rank node by number of comments
 * @return A number between 0.0 and 1.0, or -1
 */
function xmlsitemap_node_priority($node, $maxcomments) {
  if (!<