use Ottosmops\Hash\Hash;

$hash = New Hash(); // you can pass an algorithm into the constructor
$hash->createManifest($dir);
if (!$hash->verifyManifest($dir . 'manifest')) {
    print_r($this->messages);
} else {
    echo  sprintf('All files in %s have correct checksums ', $hash->manifest); 
}

$md5 = New Hash();
$md5->createManifest($dir, "myfilename", false);