static void DecodeConnAckPacket(DataReader reader, FbnsConnAckPacket packet, ref uint remainingLength)
{
packet.ConnAckFlags = reader.ReadByte();
packet.ReturnCode = (ConnectReturnCode)reader.ReadByte();
remainingLength -= 2;
if (remainingLength > 0)
{
var authSize = reader.ReadUInt16();
packet.Authentication = reader.ReadString(authSize);
remainingLength -= authSize + 2u;
if (remainingLength > 0)
{
DebugLogger.Log(nameof(FbnsPacketDecoder),
$"Unhandled data in the buffer. Length of remaining data = {remainingLength}");
}
}
}
static void DecodeConnAckPacket(IByteBuffer buffer, FbnsConnAckPacket packet, ref int remainingLength)
{
packet.ConnAckFlags = buffer.ReadByte();
packet.ReturnCode = (ConnectReturnCode)buffer.ReadByte();
remainingLength -= 2;
if (remainingLength > 0)
{
var authSize = buffer.ReadUnsignedShort();
packet.Authentication = buffer.ReadString(authSize, Encoding.UTF8);
remainingLength -= authSize + 2;
if (remainingLength > 0)
{
Debug.WriteLine(
$"FbnsPacketDecoder: Unhandled data in the buffer. Length of remaining data = {remainingLength}",
"Warning");
}
}
}
private Packet DecodePacketInternal(IByteBuffer buffer, int packetSignature, ref int remainingLength)
{
if (Signatures.IsPublish(packetSignature))
{
var qualityOfService =
(QualityOfService)((packetSignature >> 1) &
0x3); // take bits #1 and #2 ONLY and convert them into QoS value
if (qualityOfService == QualityOfService.Reserved)
{
throw new DecoderException(
$"Unexpected QoS value of {(int) qualityOfService} for {PacketType.PUBLISH} packet.");
}
bool duplicate = (packetSignature & 0x8) == 0x8; // test bit#3
bool retain = (packetSignature & 0x1) != 0; // test bit#0
var packet = new PublishPacket(qualityOfService, duplicate, retain);
DecodePublishPacket(buffer, packet, ref remainingLength);
return(packet);
}
switch (packetSignature & 240) // We don't care about flags for these packets
{
case Signatures.Subscribe& 240:
var subscribePacket = new SubscribePacket();
DecodePacketIdVariableHeader(buffer, subscribePacket, ref remainingLength);
DecodeSubscribePayload(buffer, subscribePacket, ref remainingLength);
return(subscribePacket);
case Signatures.Connect:
var connectPacket = new FbnsConnectPacket();
DecodeConnectPacket(buffer, connectPacket, ref remainingLength);
return(connectPacket);
case Signatures.PubAck:
var pubAckPacket = new PubAckPacket();
DecodePacketIdVariableHeader(buffer, pubAckPacket, ref remainingLength);
return(pubAckPacket);
case Signatures.ConnAck:
var connAckPacket = new FbnsConnAckPacket();
DecodeConnAckPacket(buffer, connAckPacket, ref remainingLength);
return(connAckPacket);
case Signatures.SubAck:
var subAckPacket = new SubAckPacket();
DecodePacketIdVariableHeader(buffer, subAckPacket, ref remainingLength);
DecodeSubAckPayload(buffer, subAckPacket, ref remainingLength);
return(subAckPacket);
case Signatures.Unsubscribe& 240:
var unsubscribePacket = new UnsubscribePacket();
DecodePacketIdVariableHeader(buffer, unsubscribePacket, ref remainingLength);
DecodeUnsubscribePayload(buffer, unsubscribePacket, ref remainingLength);
return(unsubscribePacket);
case Signatures.PingResp:
return(PingRespPacket.Instance);
default:
throw new DecoderException($"Packet type {packetSignature} not supported");
}
}