public override async Task AddByte(byte b)
{
switch (_escapeState)
{
case EscapeState.Normal:
if (b == 0x1b)
{
_escapeState = EscapeState.Escape;
break;
}
else
{
await base.AddByte(b);
}
break;
case EscapeState.Escape:
switch ((char)b)
{
case 'P':
// Start Device Control String
_escapeState = EscapeState.DcsSequence;
break;
case ']':
// Start Operating System Command
_escapeState = EscapeState.OscSequence;
break;
case '^':
// Start Privacy Message
_escapeState = EscapeState.PmSequence;
break;
case '_':
// Start Application Program Command
_escapeState = EscapeState.ApcSequence;
break;
default:
// Send the escape byte and this byte to the client
await base.AddByte(0x1b);
await base.AddByte(b);
_escapeState = EscapeState.Normal;
break;
}
break;
default:
if (_escapeState.HasFlag(EscapeState.Escape))
{
// Previous byte was escape
_escapeState &= ~EscapeState.Escape;
b = (byte)((b >= 0x40 && b <= 0x5f) ? (b + 0x40) : 0);
}
if ((b >= 0x08 && b <= 0x0d) || (b >= 0x20 && b <= 0x7e))
{
_commandStringBuilder.Append((char)b);
}
else if (b == 0x1b)
{
_escapeState |= EscapeState.Escape;
}
else if (b == 0x9C || b == 0x07)
{
// Finalise command with String Terminator or Bell.
var commandString = _commandStringBuilder.ToString();
switch (_escapeState)
{
case EscapeState.DcsSequence:
await _terminal.Dcs(commandString);
break;
case EscapeState.OscSequence:
await _terminal.Osc(commandString);
break;
case EscapeState.PmSequence:
await _terminal.Pm(commandString);
break;
case EscapeState.ApcSequence:
await _terminal.Apc(commandString);
break;
}
_commandStringBuilder.Clear();
_escapeState = EscapeState.Normal;
}
else
{
await _terminal.Error("Unexpected character in " + _escapeState.ToString());
_commandStringBuilder.Clear();
_escapeState = EscapeState.Normal;
}
break;
}
}