public Task BindAsync()
{
TaskCompletionSource <object> tcs;
lock (_gate)
{
if (_state == TransportThreadState.Started)
{
return(Task.CompletedTask);
}
else if (_state == TransportThreadState.Starting)
{
return(_stateChangeCompletion.Task);
}
else if (_state != TransportThreadState.Initial)
{
ThrowInvalidState();
}
try
{
tcs = _stateChangeCompletion = new TaskCompletionSource <object>();
_state = TransportThreadState.Starting;
_thread = new Thread(PollThread);
_thread.IsBackground = true;
_thread.Start();
}
catch
{
_state = TransportThreadState.Stopped;
throw;
}
}
return(tcs.Task);
}
public async Task StopAsync()
{
lock (_gate)
{
if (_state == TransportThreadState.Initial)
{
_state = TransportThreadState.Stopped;
return;
}
}
await UnbindAsync();
TaskCompletionSource <object> tcs = null;
bool triggerStateChange = false;
lock (_gate)
{
if (_state == TransportThreadState.Stopped)
{
return;
}
else if (_state == TransportThreadState.Stopping)
{
tcs = _stateChangeCompletion;
}
else if (_state == TransportThreadState.AcceptClosed)
{
tcs = _stateChangeCompletion = new TaskCompletionSource <object>();
_state = TransportThreadState.Stopping;
triggerStateChange = true;
}
else
{
// Cannot happen
ThrowInvalidState();
}
}
if (triggerStateChange)
{
_threadContext.RequestStopSockets();
}
await tcs.Task;
}
private void CompleteStateChange(TransportThreadState state, Exception error)
{
TaskCompletionSource <object> tcs;
lock (_gate)
{
tcs = _stateChangeCompletion;
_stateChangeCompletion = null;
_state = state;
}
ThreadPool.QueueUserWorkItem(o =>
{
if (error != null)
{
tcs?.SetException(error);
}
else
{
tcs?.SetResult(null);
}
});
}
private void CompleteStateChange(TransportThreadState state, Exception error = null)
{
_transportThread.CompleteStateChange(state, error);
}
public async Task UnbindAsync()
{
TaskCompletionSource <object> tcs = null;
lock (_gate)
{
if (_state == TransportThreadState.Initial)
{
_state = TransportThreadState.Stopped;
return;
}
else if (_state == TransportThreadState.AcceptClosed || _state == TransportThreadState.Stopping || _state == TransportThreadState.Stopped)
{
return;
}
else if (_state == TransportThreadState.ClosingAccept)
{
tcs = _stateChangeCompletion;
}
}
if (tcs != null)
{
await tcs.Task;
return;
}
try
{
await BindAsync();
}
catch
{}
bool triggerStateChange = false;
lock (_gate)
{
if (_state == TransportThreadState.AcceptClosed || _state == TransportThreadState.Stopping || _state == TransportThreadState.Stopped)
{
return;
}
else if (_state == TransportThreadState.ClosingAccept)
{
tcs = _stateChangeCompletion;
}
else if (_state == TransportThreadState.Started)
{
triggerStateChange = true;
tcs = _stateChangeCompletion = new TaskCompletionSource <object>();
_state = TransportThreadState.ClosingAccept;
}
else
{
// Cannot happen
ThrowInvalidState();
}
}
if (triggerStateChange)
{
_threadContext.RequestCloseAccept();
}
await tcs.Task;
}