// Using a template, with a constraint of IMessage allows us to pass the message without boxing reducing garbage generation
private unsafe void ReadMessage <T>(DateTime now, Command command) where T : unmanaged, IMessage
{
int length = 0;
try
{
while (length < sizeof(T))
{
length += m_SerialPort.Read(m_ReadBuffer, length, sizeof(T) - length);
}
if (length != sizeof(T))
{
throw new ArgumentException($"Message Length: {length}. Expected Length: {sizeof(T)}.");
}
}
catch (Exception e)
{
AppLogging.DebugLogException(nameof(ReadMessage), e);
Interlocked.Increment(ref m_ErrorCount);
return;
}
T message = new T();
message.SetBytes(m_ReadBuffer);
AppLogging.DebugLog(nameof(ReadMessage), command.ToString(), message.ToString());
Interlocked.Add(ref m_ReadBytes, length);
m_LastMessageRead = now;
m_MessageContext.Post(x => OnMessageRecieved?.Invoke(command, message), null);
}
private void Connect(DateTime now)
{
string[] portNames = null;
try { portNames = SerialPort.GetPortNames(); }
catch { }
if (portNames == null || portNames.Length == 0)
{
return;
}
foreach (string portName in portNames)
{
string firmware = "";
try
{
AppLogging.DebugLog(nameof(Connect), portName);
m_SerialPort = new SerialPort(portName, 115200);
m_SerialPort.ReadTimeout = k_ReadTimeout;
m_SerialPort.WriteTimeout = k_WriteTimeout;
m_SerialPort.Open();
m_SerialPort.DiscardInBuffer();
m_SerialPort.DiscardOutBuffer();
WriteMessage(now, Command.TEST);
Thread.Sleep(20);
Command command = (Command)m_SerialPort.ReadByte();
if (command != Command.TEST)
{
throw new InvalidOperationException($"Firmware Test reply failed. Reply: '{command}' Bytes: '{m_SerialPort.BytesToRead}'");
}
firmware = m_SerialPort.ReadLine().Replace("\r", "");
if (!FirmwareVersions.IsCompatible(firmware))
{
throw new ArgumentException($"Incompatible Firmware: '{firmware}'.");
}
m_SerialPort.DataReceived += Read;
m_DeviceConnected = true;
m_DeviceReady = true;
m_MessageContext.Post(x => OnDeviceConnected?.Invoke(), null);
m_LastMessageRead = now;
return;
}
catch (Exception e)
{
AppLogging.DebugLogException(nameof(Connect), e);
m_SerialPort.Close();
m_SerialPort.Dispose();
m_SerialPort = null;
if (e is ArgumentException) // Incompatible Firmware
{
m_MessageContext.Post(x => OnFirmwareIncompatible?.Invoke(firmware), null);
}
}
}
}
private void WriteMessage(DateTime now, Command command, IMessage message = null)
{
m_WriteBuffer.SetLength(0);
m_WriteBuffer.WriteByte((byte)command);
message?.GetBytes(m_WriteBuffer);
Interlocked.Add(ref m_WriteBytes, m_WriteBuffer.Length);
// GetBuffer returns a reference to the underlying array, we can still use that after we reset the position if we store the length
byte[] buffer = m_WriteBuffer.GetBuffer();
int length = (int)m_WriteBuffer.Length;
AppLogging.DebugLog(nameof(WriteMessage), command.ToString(), message != null ? message.ToString() : "");
try { m_SerialPort.Write(buffer, 0, length); }
catch (Exception e)
{
AppLogging.DebugLogException(nameof(WriteMessage), e);
return;
}
m_LastMessageWrite = now;
}
private void Read(DateTime now)
{
#if POLLING_SERIAL
try
{
if (m_SerialPort == null || !m_SerialPort.IsOpen || m_SerialPort.BytesToRead <= 0)
{
return;
}
}
catch { return; }
#endif
Command command;
try { command = (Command)m_SerialPort.ReadByte(); }
catch (Exception ex)
{
AppLogging.DebugLogException(nameof(Read), ex);
Interlocked.Increment(ref m_ErrorCount);
return;
}
Interlocked.Increment(ref m_ReadCount);
Interlocked.Increment(ref m_ReadBytes);
switch (command)
{
case Command.TEST:
{
try
{
var firmware = m_SerialPort.ReadLine().Replace("\r", "");
AppLogging.DebugLog(nameof(Read), command.ToString(), firmware);
m_LastMessageRead = now;
m_LastMessageWrite = now;
}
catch (Exception e)
{
AppLogging.DebugLogException(nameof(ReadMessage), e);
Interlocked.Increment(ref m_ErrorCount);
return;
}
}
break;
case Command.OK:
{
AppLogging.DebugLog(nameof(Read), command.ToString());
m_DeviceReady = true;
m_LastMessageRead = now;
m_LastMessageWrite = now;
Write(m_LastMessageRead);
}
break;
case Command.SETTINGS:
ReadMessage <DeviceSettings>(now, command);
break;
case Command.SESSION_INFO:
ReadMessage <SessionInfo>(now, command);
break;
case Command.CURRENT_SESSION:
case Command.ALTERNATE_SESSION:
case Command.PREVIOUS_SESSION:
case Command.NEXT_SESSION:
ReadMessage <SessionData>(now, command);
break;
case Command.VOLUME_CURR_CHANGE:
case Command.VOLUME_ALT_CHANGE:
case Command.VOLUME_PREV_CHANGE:
case Command.VOLUME_NEXT_CHANGE:
ReadMessage <VolumeData>(now, command);
break;
case Command.MODE_STATES:
ReadMessage <ModeStates>(now, command);
break;
case Command.ERROR:
case Command.NONE:
case Command.DEBUG:
Interlocked.Increment(ref m_ErrorCount);
break;
}
}
