/// <summary>
/// Send a message to the client. Cancelling <paramref name="ct"/> during WriteAsync
/// will result in a lost connection. Thread-safe.
/// </summary>
/// <param name="msg"></param>
/// <param name="ct"></param>
/// <param name="log"></param>
/// <returns>True if message sent. False if connection lost.</returns>
public async Task <bool> WriteAsync(string msg, CancellationToken ct, bool log = false)
{
const string funcName = nameof(WriteAsync);
if (ConnectionStatus == ConnectionStatusEnum.Disconnected)
{
return(false);
}
if (log)
{
Log.DebugEx(funcName, $"[{_logName}] Sending message {msg}", false);
}
// Add end chars here
var msgBytes = Encoding.UTF8.GetBytes(msg + (_implicitEndOfMessageString ? _endOfMessageString : string.Empty));
await _sendMessageLock.WaitAsync(ct); // Lock
try
{
using (ct.Register(() => _tcpStream.Dispose()))
{
// NetworkStream does not override WriteAsync.
// This means that it will get the default behavior
// of Stream.WriteAsync which just throws the token away after checking it initially.
// Disposing _tcpStream cancels the write operation.
//
// Throw IOException when write fails.
// Throw ObjectDisposedException when stream disposed.
await _tcpStream.WriteAsync(msgBytes, 0, msgBytes.Length, ct);
return(true);
}
}
catch (Exception e) when(e is ObjectDisposedException || e is IOException)
{
_sendMessageFailedSignal.TryRelease();
ct.ThrowIfCancellationRequested();
return(false);
}
finally
{
_sendMessageLock.Release(); // Release
}
}
