/** * Encode the header section of the message * * @param \LibDNS\Encoder\EncodingContext $encodingContext * @param \LibDNS\Messages\Message $message * @return string * @throws \UnexpectedValueException When the header section is invalid */ private function encodeHeader(EncodingContext $encodingContext, Message $message) { $header = ['id' => $message->getID(), 'meta' => 0, 'qd' => $message->getQuestionRecords()->count(), 'an' => $message->getAnswerRecords()->count(), 'ns' => $message->getAuthorityRecords()->count(), 'ar' => $message->getAdditionalRecords()->count()]; $header['meta'] |= $message->getType() << 16; $header['meta'] |= $message->getOpCode() << 11; $header['meta'] |= (int) $message->isAuthoritative() << 10; $header['meta'] |= (int) $encodingContext->isTruncated() << 9; $header['meta'] |= (int) $message->isRecursionDesired() << 8; $header['meta'] |= (int) $message->isRecursionAvailable() << 7; $header['meta'] |= $message->getResponseCode(); return pack('n*', $header['id'], $header['meta'], $header['qd'], $header['an'], $header['ns'], $header['ar']); }