initial ack controlflow implementation

1 files changed, 54 insertions, 2 deletions

diff --git a/saprotocol.cc b/saprotocol.cc
index 22b3111..94594a1 100644
--- a/saprotocol.cc
+++ b/saprotocol.cc
@@ -219,11 +219,11 @@ QByteArray SAProtocol::packFrame(const Frame &frame)
 	return data.prepend(reinterpret_cast<char*>(&header), 2);
 }
 
-QByteArray SAProtocol::packFrame(quint16 sessionId, const QByteArray &data)
+QByteArray SAProtocol::packFrame(quint16 sessionId, const QByteArray &data, FrameType type)
 {
 	Frame frame;
 	frame.protocolVersion = currentProtocolVersion;
-	frame.type = FrameData;
+	frame.type = type;
 	frame.sessionId = sessionId;
 	frame.data = data;
 	return packFrame(frame);
@@ -253,6 +253,58 @@ QByteArray SAProtocol::packDataFrame(const DataFrame &frame)
 	return data;
 }
 
+SAProtocol::ControlFrame SAProtocol::unpackControlFrame(const QByteArray &data)
+{
+	ControlFrame frame;
+	int offset = 0;
+	int num_ranges;
+
+	frame.type = static_cast<ControlFrameType>(read<quint8>(data, offset));
+
+	switch (frame.type) {
+	case ControlFrameImmediateAck:
+	case ControlFrameBlockAck:
+		frame.seqNum = read<quint16>(data, offset);
+		break;
+	case ControlFrameNak:
+		num_ranges = read<quint8>(data, offset);
+		frame.seqNums.reserve(num_ranges);
+		for (int i = 0; i < num_ranges; i++) {
+			SeqNumRange r;
+			r.first = read<quint8>(data, offset);
+			r.second = read<quint8>(data, offset);
+			frame.seqNums.append(r);
+		}
+		break;
+	default:
+		qWarning() << "Unknown frame type";
+		break;
+	}
+
+	return frame;
+}
+
+QByteArray SAProtocol::packControlFrame(const ControlFrame &frame)
+{
+	QByteArray data;
+	append<quint8>(data, frame.type);
+	switch (frame.type) {
+	case ControlFrameImmediateAck:
+	case ControlFrameBlockAck:
+		Q_ASSERT(frame.seqNums.empty());
+		append<quint16>(data, frame.seqNum);
+		break;
+	case ControlFrameNak:
+		append<quint8>(data, frame.seqNums.size());
+		foreach (const SeqNumRange &r, frame.seqNums) {
+			append<quint16>(data, r.first);
+			append<quint16>(data, r.second);
+		}
+		break;
+	}
+	return data;
+}
+
 SAProtocol::ServiceConnectionRequestFrame SAProtocol::unpackServiceConnectionRequestFrame(const QByteArray &data)
 {
 	ServiceConnectionRequestFrame frame;