/// <summary>
/// Essential Rx method. Drives state machine by reading data and processing it. This works in
/// conjunction with NotificationThreadWorker [Tx].
/// </summary>
internal async Task <IncomingMessage> ProcessAsync(CancellationToken cancellationToken)
{
int count;
int bytesRead;
try
{
switch (m_state)
{
case ReceiveState.Initialize:
if (cancellationToken.IsCancellationRequested)
{
// cancellation requested
Debug.WriteLine("cancel token");
return(null);
}
m_rawPos = 0;
m_base = new MessageBase();
m_base.m_header = new Packet();
m_raw = new MessageRaw();
m_raw.m_header = m_parent.CreateConverter().Serialize(m_base.m_header);
m_state = ReceiveState.WaitingForHeader;
DebuggerEventSource.Log.WireProtocolReceiveState(m_state);
goto case ReceiveState.WaitingForHeader;
case ReceiveState.WaitingForHeader:
count = m_raw.m_header.Length - m_rawPos;
Debug.WriteLine("WaitingForHeader");
// need to have a timeout to cancel the read task otherwise it may end up waiting forever for this to return
// because we have an external cancellation token and the above timeout cancellation token, need to combine both
bytesRead = await m_parent.ReadBufferAsync(m_raw.m_header, m_rawPos, count, request.waitRetryTimeout, cancellationToken.AddTimeout(request.waitRetryTimeout)).ConfigureAwait(false);
m_rawPos += bytesRead;
// sanity check
if (bytesRead != 32)
{
// doesn't look like a header, better restart
m_state = ReceiveState.Initialize;
goto case ReceiveState.Initialize;
}
while (m_rawPos > 0)
{
int flag_Debugger = ValidSignature(marker_Debugger);
int flag_Packet = ValidSignature(marker_Packet);
if (flag_Debugger == 1 || flag_Packet == 1)
{
m_state = ReceiveState.ReadingHeader;
DebuggerEventSource.Log.WireProtocolReceiveState(m_state);
goto case ReceiveState.ReadingHeader;
}
if (flag_Debugger == 0 || flag_Packet == 0)
{
break; // Partial match.
}
m_parent.App.SpuriousCharacters(m_raw.m_header, 0, 1);
Array.Copy(m_raw.m_header, 1, m_raw.m_header, 0, --m_rawPos);
}
break;
case ReceiveState.ReadingHeader:
count = m_raw.m_header.Length - m_rawPos;
Debug.WriteLine("ReadingHeader");
// need to have a timeout to cancel the read task otherwise it may end up waiting forever for this to return
// because we have an external cancellation token and the above timeout cancellation token, need to combine both
bytesRead = await m_parent.ReadBufferAsync(m_raw.m_header, m_rawPos, count, request.waitRetryTimeout, cancellationToken.AddTimeout(request.waitRetryTimeout)).ConfigureAwait(false);
m_rawPos += bytesRead;
if (bytesRead != count)
{
break;
}
m_state = ReceiveState.CompleteHeader;
DebuggerEventSource.Log.WireProtocolReceiveState(m_state);
goto case ReceiveState.CompleteHeader;
//break;
case ReceiveState.CompleteHeader:
try
{
Debug.WriteLine("CompleteHeader");
m_parent.CreateConverter().Deserialize(m_base.m_header, m_raw.m_header);
if (VerifyHeader() == true)
{
Debug.WriteLine("CompleteHeader, header OK");
bool fReply = (m_base.m_header.m_flags & Flags.c_Reply) != 0;
DebuggerEventSource.Log.WireProtocolRxHeader(m_base.m_header.m_crcHeader, m_base.m_header.m_crcData, m_base.m_header.m_cmd, m_base.m_header.m_flags, m_base.m_header.m_seq, m_base.m_header.m_seqReply, m_base.m_header.m_size);
if (m_base.m_header.m_size != 0)
{
m_raw.m_payload = new byte[m_base.m_header.m_size];
//reuse m_rawPos for position in header to read.
m_rawPos = 0;
m_state = ReceiveState.ReadingPayload;
DebuggerEventSource.Log.WireProtocolReceiveState(m_state);
goto case ReceiveState.ReadingPayload;
}
else
{
m_state = ReceiveState.CompletePayload;
DebuggerEventSource.Log.WireProtocolReceiveState(m_state);
goto case ReceiveState.CompletePayload;
}
}
Debug.WriteLine("CompleteHeader, header not valid");
}
//catch (ThreadAbortException)
//{
// throw;
//}
catch (Exception e)
{
Debug.WriteLine("Fault at payload deserialization:\n\n{0}", e.ToString());
}
m_state = ReceiveState.Initialize;
DebuggerEventSource.Log.WireProtocolReceiveState(m_state);
if ((m_base.m_header.m_flags & Flags.c_NonCritical) == 0)
{
// FIXME
// evaluate the purpose of this reply back to the NanoFramework device, the nanoCLR doesn't seem to have to handle this. In the end it looks like this does have any real purpose and will only be wasting CPU.
//await IncomingMessage.ReplyBadPacketAsync(m_parent, Flags.c_BadHeader).ConfigureAwait(false);
return(null);
}
break;
case ReceiveState.ReadingPayload:
count = m_raw.m_payload.Length - m_rawPos;
Debug.WriteLine("ReadingPayload");
// need to have a timeout to cancel the read task otherwise it may end up waiting forever for this to return
// because we have an external cancellation token and the above timeout cancellation token, need to combine both
bytesRead = await m_parent.ReadBufferAsync(m_raw.m_payload, m_rawPos, count, request.waitRetryTimeout, cancellationToken.AddTimeout(request.waitRetryTimeout)).ConfigureAwait(false);
m_rawPos += bytesRead;
if (bytesRead != count)
{
break;
}
m_state = ReceiveState.CompletePayload;
DebuggerEventSource.Log.WireProtocolReceiveState(m_state);
goto case ReceiveState.CompletePayload;
case ReceiveState.CompletePayload:
Debug.WriteLine("CompletePayload");
if (VerifyPayload() == true)
{
Debug.WriteLine("CompletePayload payload OK");
try
{
bool fReply = (m_base.m_header.m_flags & Flags.c_Reply) != 0;
if ((m_base.m_header.m_flags & Flags.c_NACK) != 0)
{
m_raw.m_payload = null;
}
if (await ProcessMessage(GetCompleteMessage(), fReply).ConfigureAwait(false))
{
DebuggerEventSource.Log.WireProtocolReceiveState(m_state);
//Debug.WriteLine("*** leaving reassembler");
return(GetCompleteMessage());
}
else
{
// this is not the message we were waiting
// FIXME
}
//m_parent.App.ProcessMessage(this.GetCompleteMessage(), fReply);
//m_state = ReceiveState.Initialize;
//return;
}
//catch (ThreadAbortException)
//{
// throw;
//}
catch (Exception e)
{
Debug.WriteLine("Fault at payload deserialization:\n\n{0}", e.ToString());
}
}
else
{
Debug.WriteLine("CompletePayload payload not valid");
}
m_state = ReceiveState.Initialize;
DebuggerEventSource.Log.WireProtocolReceiveState(m_state);
if ((m_base.m_header.m_flags & Flags.c_NonCritical) == 0)
{
// FIXME
// evaluate the purpose of this reply back to the NanoFramework device, the nanoCLR doesn't seem to have to handle this. In the end it looks like this does have any real purpose and will only be wasting CPU.
await IncomingMessage.ReplyBadPacketAsync(m_parent, Flags.c_BadPayload).ConfigureAwait(false);
return(null);
}
break;
}
}
catch
{
m_state = ReceiveState.Initialize;
DebuggerEventSource.Log.WireProtocolReceiveState(m_state);
Debug.WriteLine("*** EXCEPTION ***");
throw;
}
Debug.WriteLine("??????? leaving reassembler");
return(null);
}
public async Task <bool> ProcessMessage(IncomingMessage msg, bool fReply)
{
msg.Payload = Commands.ResolveCommandToPayload(msg.Header.m_cmd, fReply, m_parent.Capabilities);
if (fReply == true)
{
Request reply = null;
if (request.MatchesReply(msg))
{
reply = request;
// FIXME: check if this return can happen here without the QueueNotify call bellow
return(true);
}
else
if (reply != null)
{
// FIXME
reply.Signal(msg);
return(true);
}
}
else
{
Packet bp = msg.Header;
switch (bp.m_cmd)
{
case Commands.c_Monitor_Ping:
{
Commands.Monitor_Ping.Reply cmdReply = new Commands.Monitor_Ping.Reply();
cmdReply.m_source = Commands.Monitor_Ping.c_Ping_Source_Host;
// FIXME
//cmdReply.m_dbg_flags = (m_stopDebuggerOnConnect ? Commands.Monitor_Ping.c_Ping_DbgFlag_Stop : 0);
await msg.ReplyAsync(m_parent.CreateConverter(), Flags.c_NonCritical, cmdReply).ConfigureAwait(false);
//m_evtPing.Set();
return(true);
}
case Commands.c_Monitor_Message:
{
Commands.Monitor_Message payload = msg.Payload as Commands.Monitor_Message;
Debug.Assert(payload != null);
if (payload != null)
{
// FIXME
//QueueNotify(m_eventMessage, msg, payload.ToString());
}
return(true);
}
case Commands.c_Debugging_Messaging_Query:
case Commands.c_Debugging_Messaging_Reply:
case Commands.c_Debugging_Messaging_Send:
{
Debug.Assert(msg.Payload != null);
if (msg.Payload != null)
{
// FIXME
//QueueRpc(msg);
}
return(true);
}
}
}
// FIXME
//if (m_eventCommand != null)
//{
// QueueNotify(m_eventCommand, msg, fReply);
// return true;
//}
return(false);
}