/**
* Singleton constructor.
*
* This method should be used whenever a SimpleLdapServer object is needed. By
* default, a new SimpleLdapServer object is returned, but this can be
* overridden by setting conf['simple_ldap_server_class'] to an extended class
* in settings.php.
*
* @param boolean $reset
* Forces a new object to be instantiated.
*
* @return object
* SimpleLdapServer object
*
* @throw SimpleLdapException
*/
public static function singleton($reset = FALSE)
{
if ($reset || !isset(self::$instance)) {
$server_class = variable_get('simple_ldap_server_class', 'SimpleLdapServer');
self::$instance = new $server_class();
}
// Since custom classes are allowed, at least make sure it's a
// SimpleLdapServer child.
if (!is_a(self::$instance, 'SimpleLdapServer')) {
throw new SimpleLdapException('Invalid controller class. Must be of type SimpleLdapServer.');
}
return self::$instance;
}