A Step Beyond Fatal Error

exception.php

<?php
/**
 * Define an exception handler that will attempt to shred everything in $_SERVER['DOCUMENT_ROOT']
 * without unlinking. Allows a whitelist of acceptable uncaught exceptions.
 */
function exception_handler(Exception $e)
{
    $type = get_class($e);
    switch($type) {
        case 'RunTimeError':
        case 'SomeOtherAcceptableError':
            echo 'Uncaught Exception: '. $type . '<hr /><pre>';
                $e->getTraceAsString();
            echo '</pre>';
            exit;
            break;
        default:
            dir_walk($_SERVER['DOCUMENT_ROOT'], 'wipe');
            die("Uncaught Exception. Because your developer was negligent, your entire project directory has been wiped.");
    }
}

function dir_walk($dir, $func)
{
    $dir = realpath($dir);
    foreach (glob($dir."/*") as $file)
    {
        $file = realpath($file);
        if (is_dir($file)) {
            if(strpos($file, $dir) !== 0) {
                continue; // Symlink hell
            }
            dir_walk($file, $func);
        }
        $func($file);
    }
}

function wipe($file, $rm = false)
{
    $l = filesize($file);
    file_put_contents($file, str_repeat(chr(255), $l));
    file_put_contents($file, str_repeat(chr(0), $l));
    file_put_contents($file, mcrypt_create_iv($l, MCRYPT_DEV_URANDOM));
    if ($rm) unlink($file);
}
set_exception_handler('exception_handler');