Php prosty skrypt logowania biała strona

Cześć im próbuje wszczepić PDO do mojego skryptu logowania, by uczynić go safrer od wtrysku sql. Ale im uzyskać białą stronę myślę, że to dlatego, że próbuję policzyć wiersze, aby sprawdzić, czy użytkownik jest prawdziwy .....

// Here we inculde the function page
include 'functions/functions.php';
// Here we connect to the db
$db = mysqlconnect();

$password = md5($_POST['mypassword']);
$statement = $db->prepare("SELECT * FROM users WHERE username = ? AND password = ?");
$statement->execute(array($_POST['myusername'], $password));


// Replace counting function based on database you are using.
 $count = $statement->rowCount();
// If result matched $myusername and $mypassword, table row must be 1 row

if($count == 1){
  // Register $myusername, $mypassword and redirect to file "login_success.php"

$_SESSION['username'] = $myusername ;


//Test if it is a shared client
if (!empty($_SERVER['HTTP_CLIENT_IP'])){
  $ip=$_SERVER['HTTP_CLIENT_IP'];
//Is it a proxy address
}elseif (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])){
  $ip=$_SERVER['HTTP_X_FORWARDED_FOR'];
}else{
  $ip=$_SERVER['REMOTE_ADDR'];
}


$updateinfo=mysql_query("UPDATE `users` SET lastip ='$ip' WHERE `username` = '".$_SESSION['username']."'");
mysql_query("INSERT INTO user_log 
(username, ip) VALUES('".$_SESSION['username']."', '$ip' ) ") 
or die(mysql_error());  





header("Location: home.php");
} else {
  echo "Wrong Username or Password";
}


echo"<p> </p>";

Nie dostaję żadnego błędu, tylko biała strona.

Również tutaj znajduje się moja strona funkcyjna, którą uwzględniam

    function mysqlconnect(){
     global $db;
    $host = 'localhost';
    $port = 3306; // This is the default port for MySQL
    $database = '';
    $username = '';
    $password = '';

    // Construct the DSN, or "Data Source Name".  Really, it's just a fancy name
    // for a string that says what type of server we're connecting to, and how
    // to connect to it.  As long as the above is filled out, this line is all
    // you need :)
    $dsn = "mysql:host=$host;port=$port;dbname=$database";

    // Connect!
    $db = new PDO($dsn, $username, $password);

}

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