function _hash($data, $controlType)
{
switch ($controlType) {
case 'md5':
return md5($data);
case 'crc32':
return sprintf('% 32d', crc32($data));
case 'strlen':
return sprintf('% 32d', strlen($data));
default:
$this->raiseError('Unknown controlType ! ' . '(available values are only \'md5\', \'crc32\', \'strlen\')', -5);
}
}