Why does this simple code timeout?

[ro0bear]

This function works perfectly if the while condition is ($q > 1) but it gets a "Error 500 - Internal server error" if the condition is ($q > 2) or higher than 3. Why is this happening? I can't work it out.

The function takes an array such as array('box', 'item') and then searches to see if there is post variables such as:

box_0:item_0
box_0:item_1
box_0:item_2

box_1:item_0
box_1:item_1

box_2:item_0
box_2:item_0

and then returns an array that looks like this array('box0:item', 'box1:item', 'box2:item')

It doesn't really matter what the function is achieving exactly, I just don't understand why I get the error after so few iterations.

function ConstructPostArray($variable_parts_array) {

    $o = count($variable_parts_array);
    $q = 0;

    for ($i = 0; $i < ($o - 1); ++$i) {

        $array_level[$i] = 0;

    }

    $last = ($i - 1);

    while ($q < 3) {


        for ($i = 0, $postname=''; $i < $o; ++$i) {

            if (($i + 1) < $o) {

                $postname .= $variable_parts_array[$i] . '_' . $array_level[$i] . ':';

            } else {

                $postname .= $variable_parts_array[$i];

            }

        }
        
        if (isset($_POST[$postname . '_0'])) {
            $postname_array[$q] = $postname;
            ++$array_level[$last];
            ++$q;
        }        
    }
    

    return $postname_array;



} 

Any help would be much appreciated

Thank you, ro0bear

[Shrapnel_N5]

is there while ($q < 3) or ($q > 3) ?

[ro0bear]

is there while ($q < 3) or ($q > 3) ?

nope, the code is exactly as you see it:

while ($q > 0) (works)
while ($q > 1) (works)
while ($q > 2) (Error 500 - Internal server error)
while ($q > 3) (Error 500 - Internal server error)

[Mal Curtis]

The code has a less than not a greater than? I imagine the server error is probably your recursion limit has been reached as the while loop condition is always true?

[JamesColin]

It's because of this part:
if (isset($_POST[$postname . '_0'])) {

which at some point is never true, so the ++$q is never executed again and $q will always be < 3 so the while() loop is infinite and the error 500 might simply be a time out, you'd need to check the error log to see more information about the error.

[ro0bear]

Thanks guys! Seems so obvious now lol.

Much appreciated, ro0bear