(Re)populate the database tables used by various menu functions.

This function will clear and populate the {menu_router} table, add entries to {menu_links} for new router items, then remove stale items from {menu_links}. If called from update.php or install.php, it will also schedule a call to itself on the first real page load from menu_execute_active_handler(), because the maintenance page environment is different and leaves stale data in the menu tables.

Related topics

File

drupal-6.x/includes/menu.inc, line 1695

API for the Drupal menu system.

Code

function menu_rebuild() {
  if (!lock_acquire('menu_rebuild')) {
    // Wait for another request that is already doing this work.
    // We choose to block here since otherwise the router item may not 
    // be avaiable in menu_execute_active_handler() resulting in a 404.
    lock_wait('menu_rebuild');
    return FALSE;
  }

  $menu = menu_router_build(TRUE);
  _menu_navigation_links_rebuild($menu);
  // Clear the menu, page and block caches.
  menu_cache_clear_all();
  _menu_clear_page_cache();

  if (defined('MAINTENANCE_MODE')) {
    variable_set('menu_rebuild_needed', TRUE);
  }
  else {
    variable_del('menu_rebuild_needed');
  }
  lock_release('menu_rebuild');
  return TRUE;
}