public void Unmarshal(TransportPacket input, ITransportDeliveryCharacteristics tdc, EventHandler<MessageEventArgs> messageAvailable)
{
// <item>Message fits within the transport packet length, so sent unmodified
// <pre>[byte:message-type] [byte:channelId] [uint32:packet-size]
// [bytes:content]</pre>
// </item>
// <item> if the message is the first fragment, then the high-bit is
// set on the message-type; the number of fragments is encoded using
// the adaptive <see cref="ByteUtils.EncodeLength(int)"/> format.
// <pre>[byte:message-type'] [byte:channelId] [uint32:packet-size]
// [byte:seqno] [bytes:encoded-#-fragments] [bytes:frag]</pre>
// </item>
// <item> for all subsequent fragments; seqno' = seqno | 128;
// the number of fragments is encoded using the adaptive
// <see cref="ByteUtils.EncodeLength(int)"/> format.
// <pre>[byte:message-type'] [byte:channelId] [uint32:packet-size]
// [byte:seqno'] [bytes:encoded-fragment-#] [bytes:frag]</pre>
// Fastpath: if the message-type doesn't have the high-bit set,
// then this is a non-fragmented message
if ((input.ByteAt(0) & 128) == 0)
{
// If the submarshaller uses LWMCFv1.1 then we would have just
// sent the packet as-is; if not, then we'll have prefixed a
// LWMCFv1.1 header which must be first removed
if (!subMarshallerIsLwmcf11)
{
input.RemoveBytes(0, (int)LWMCFv11.HeaderSize);
}
subMarshaller.Unmarshal(input, tdc, messageAvailable);
return;
}
MessageType type;
byte channelId;
uint contentLength;
Stream s = input.AsReadStream();
LWMCFv11.DecodeHeader(out type, out channelId, out contentLength, s);
byte seqNo = (byte)s.ReadByte();
TransportPacket subPacket;
if ((seqNo & 128) == 0)
{
// This starts a new message
uint numFrags = (uint)ByteUtils.DecodeLength(s);
subPacket = UnmarshalFirstFragment(seqNo, numFrags,
input.SplitOut((int)(s.Length - s.Position)), tdc);
}
else
{
// This is a message in progress
seqNo = (byte)(seqNo & ~128);
uint fragNo = (uint)ByteUtils.DecodeLength(s);
subPacket = UnmarshalFragInProgress(seqNo, fragNo,
input.SplitOut((int)(s.Length - s.Position)), tdc);
}
if (subPacket != null)
{
subMarshaller.Unmarshal(subPacket, tdc, messageAvailable);
subPacket.Dispose();
}
}