public function ssologin()
 {
     $auth = mod_login::instance();
     if ($auth->is_login()) {
         $this->frame();
     }
     $sign = $_GET['sign'];
     if (!$sign) {
         header("Location: http://fladminsso.feiliu.com/?source=" . rawurlencode(BASE_URL . '?c=login&a=ssologin'));
     }
     $ret = ffile_get_contents("http://fladminsso.feiliu.com/client/check/{$sign}");
     $retinfo = json_decode($ret, 1);
     if ($retinfo['code'] == 0) {
         $retuinfo = $retinfo['userinfo'];
         $userdata['username'] = $retuinfo['login_name'];
         $userdata['password'] = $retuinfo['password'];
         if ($auth->authenticate($userdata, 'sso')) {
             mod_member::loginhistory(USERNAME);
             header("Location: " . BASE_URL);
             exit;
         }
     } else {
         header("Location: http://fladminsso.feiliu.com/?source=" . rawurlencode(BASE_URL . '?c=login&a=ssologin'));
         exit;
     }
 }
 public static function instance()
 {
     if (self::$instance === null) {
         self::$instance = new mod_login();
     }
     return self::$instance;
 }
 function __construct()
 {
     $auth = mod_login::instance();
     if (!$auth->is_login()) {
         header("location: ./");
     }
     if (!$_GET['c']) {
         header("location: ./");
     }
 }