internal Task <bool> Start(LinkedListNode <Request> node, CancellationToken token, int timeout)
{
this.token = token;
// register a cancellation callback if the token is cancellable, i.e., is not CancellationToken.None
if (token.CanBeCanceled)
{
// Note that if the token is already cancelled, the callback is called synchronously!
cancelRegist = token.Register(() => sem.CancellationCallback(node));
}
// Create a timer if timeout is not infinite
// and the task can be already completed due to a premature cancellation
if (timeout != Timeout.Infinite && !Task.IsCompleted)
{
timer = new Timer((o) => sem.TimeoutCallback(node), null, timeout, Timeout.Infinite);
}
// return the promise associated task
return(Task);
}
