logout.php :
----------

                        <?php
                                session_start();
                                if (isset($_SESSION['logged']) && $_SESSION['logged'] == 1)
                                {
                                    if(isset($_COOKIE['hamusername']) && isset($_COOKIE['hampassword']))
                                    {
                                        setcookie("hamusername", "", time()-60*60*24*100, "/");
                                        setcookie("hampassword", "", time()-60*60*24*100, "/");
                                    }

                                    session_destroy();
                                    header("Location: index.php");
                                }
                                else
                                    header("Location: index.php");
                            ?>


header.php :
----------




        if(isset($_COOKIE['hamusername']) && isset($_COOKIE['hampassword']))
        {
            $username = $_COOKIE["hamusername"];
            $password = $_COOKIE["hampassword"];

            $q = $db->prepare("SELECT * FROM `users` WHERE username = ? AND password = ?");
            $q->execute(array($username, $password));
            $is_logged_count = $q->rowCount();
            $row = $q->fetch(PDO::FETCH_OBJ);

            if ($is_logged_count == 1)
            {
                $_SESSION['user_id'] = $row->id;
                $_SESSION['logged'] = 1;
            }
        }
        else
        {
            unset($_COOKIE['hamusername']);
            unset($_COOKIE["hampassword"]);
        }