PHP session destroy Trying to destroy uninitialized session

Question

I\'ve read several topics like:

Error — session_destroy() — Trying to destroy uninitialized session, Warning: session_destroy(): Trying to destroy uninitialized session

Answer 1

The problem is that you call session destroy twice. If $_COOKIE['data'] is not set, then $_COOKIE['data'] != sha1($_SESSION['email']) will return false as well and it will try to destroy the session again.

    if(!isset($_COOKIE['data'])){
        session_destroy();
        $this->error_404();
    }

    if($_COOKIE['data'] != sha1($_SESSION['email'])){
        session_destroy();
        unset($_COOKIE["data"]);
        setcookie("data", false, time() - 3600, '/');
        $this->error_404();
    }

Make the checks on in another

     if($_COOKIE['data'] != sha1($_SESSION['email'])){
        if(!isset($_COOKIE['data'])){
        session_destroy();
        $this->error_404();
        }
        else
        {
        unset($_COOKIE["data"]);
        setcookie("data", false, time() - 3600, '/');
        session_destroy();
        $this->error_404();
        }
    }

If the cookie data is not valid, it may be because there is no cookie. This way, if it's not valid, it checks if it exists. If it does exist and it's not valid, it does something. If it doesn't, it does something else.