public sealed override Task ConnectAsync(EndPoint remoteAddress, EndPoint localAddress)
{
// todo: handle cancellation
AbstractSocketChannel ch = this.Channel;
if (!ch.Open)
{
return(this.CreateClosedChannelExceptionTask());
}
try
{
if (ch.connectPromise != null)
{
throw new InvalidOperationException("connection attempt already made");
}
bool wasActive = this.channel.Active;
if (ch.DoConnect(remoteAddress, localAddress))
{
this.FulfillConnectPromise(wasActive);
return(TaskEx.Completed);
}
else
{
ch.connectPromise = new TaskCompletionSource(remoteAddress);
// Schedule connect timeout.
TimeSpan connectTimeout = ch.Configuration.ConnectTimeout;
if (connectTimeout > TimeSpan.Zero)
{
ch.connectCancellationTask = ch.EventLoop.Schedule(
(c, a) =>
{
// todo: make static / cache delegate?..
var self = (AbstractSocketChannel)c;
// todo: call Socket.CancelConnectAsync(...)
TaskCompletionSource promise = self.connectPromise;
var cause = new ConnectTimeoutException("connection timed out: " + a.ToString());
if (promise != null && promise.TrySetException(cause))
{
self.CloseAsync();
}
},
this.channel,
remoteAddress,
connectTimeout);
}
ch.connectPromise.Task.ContinueWith(
(t, s) =>
{
var c = (AbstractSocketChannel)s;
c.connectCancellationTask?.Cancel();
c.connectPromise = null;
c.CloseAsync();
},
ch,
TaskContinuationOptions.OnlyOnCanceled | TaskContinuationOptions.ExecuteSynchronously);
return(ch.connectPromise.Task);
}
}
catch (Exception ex)
{
this.CloseIfClosed();
return(TaskEx.FromException(this.AnnotateConnectException(ex, remoteAddress)));
}
}
