I need to know how many days are involved in a date diff. \For example:

<?

$start = new DateTime('2014-06-29 14:00:00');
$ende = new DateTime('2014-07-02 05:45:00');

$diff = $start->diff($ende);

echo $diff->format('%R');
echo $diff->days;
?>

The above code echos +2

My desired result would be 4, because the 29th, 30th, 1st and 2nd of July are "touched". I have no idea to achieve that with the given functions. Coding a day-subtraction seems to bean open door for errors.