public override ValueTask <ConnectionContext> ConnectAsync(IFeatureCollection?features = null, CancellationToken cancellationToken = default)
{
QuicStream quicStream;
var streamDirectionFeature = features?.Get <IStreamDirectionFeature>();
if (streamDirectionFeature != null)
{
if (streamDirectionFeature.CanRead)
{
quicStream = _connection.OpenBidirectionalStream();
}
else
{
quicStream = _connection.OpenUnidirectionalStream();
}
}
else
{
quicStream = _connection.OpenBidirectionalStream();
}
// Only a handful of control streams are created by the server and they last for the
// lifetime of the connection. No value in pooling them.
QuicStreamContext?context = new QuicStreamContext(this, _context);
context.Initialize(quicStream);
context.Start();
QuicLog.ConnectedStream(_log, context);
return(new ValueTask <ConnectionContext>(context));
}
public override async ValueTask <ConnectionContext?> AcceptAsync(CancellationToken cancellationToken = default)
{
try
{
var stream = await _connection.AcceptInboundStreamAsync(cancellationToken);
QuicStreamContext?context = null;
// Only use pool for bidirectional streams. Just a handful of unidirecitonal
// streams are created for a connection and they live for the lifetime of the connection.
if (stream.CanRead && stream.CanWrite)
{
lock (_poolLock)
{
StreamPool.TryPop(out context);
}
}
if (context == null)
{
context = new QuicStreamContext(this, _context);
context.Initialize(stream);
}
else
{
context.ResetFeatureCollection();
context.ResetItems();
context.Initialize(stream);
QuicLog.StreamReused(_log, context);
}
context.Start();
QuicLog.AcceptedStream(_log, context);
return(context);
}
catch (QuicException ex) when(ex.QuicError == QuicError.ConnectionAborted)
{
// Shutdown initiated by peer, abortive.
_error = ex.ApplicationErrorCode;
QuicLog.ConnectionAborted(_log, this, ex.ApplicationErrorCode.GetValueOrDefault(), ex);
ThreadPool.UnsafeQueueUserWorkItem(state =>
{
state.CancelConnectionClosedToken();
},
this,
preferLocal: false);
// Throw error so consumer sees the connection is aborted by peer.
throw new ConnectionResetException(ex.Message, ex);
}
catch (QuicException ex) when(ex.QuicError == QuicError.OperationAborted)
{
lock (_shutdownLock)
{
// This error should only happen when shutdown has been initiated by the server.
// If there is no abort reason and we have this error then the connection is in an
// unexpected state. Abort connection and throw reason error.
if (_abortReason == null)
{
Abort(new ConnectionAbortedException("Unexpected error when accepting stream.", ex));
}
_abortReason !.Throw();
}
}
catch (OperationCanceledException)
{
Debug.Assert(cancellationToken.IsCancellationRequested, "Error requires cancellation is requested.");
lock (_shutdownLock)
{
// Connection has been aborted. Throw reason exception.
_abortReason?.Throw();
}
}
catch (Exception ex)
{
Debug.Fail($"Unexpected exception in {nameof(QuicConnectionContext)}.{nameof(AcceptAsync)}: {ex}");
throw;
}
// Return null for graceful closure or cancellation.
return(null);
}