public bool Remove(TCompletion continuation)
{
if (Interlocked.CompareExchange(ref single, null, continuation) == continuation)
{
return(true);
}
if (completed != null)
{
return(completed.Remove(continuation));
}
return(false);
}
public bool Remove(TCompletion continuation)
{
TCompletion temp = single;
if (temp != null && temp == continuation)
{
single = null;
return(true);
}
if (completed != null)
{
return(completed.Remove(continuation));
}
return(false);
}
public Task <bool> WaitAsync(Int32 duration, CancellationToken token)
{
VerboseLog("{0:000}|{1}|async wait requested", Thread.CurrentThread.Id, _id);
CheckDisposed();
token.ThrowIfCancellationRequested();
if (_sem.TryAcquire())
{
VerboseLog("{0:000}|{1}|async wait immediate success", Thread.CurrentThread.Id, _id);
return(Task.FromResult(true));
}
if (duration == 0)
{
return(Task.FromResult(false));
}
if (_asyncWaiters == null)
{
lock (this)
{
if (_asyncWaiters == null)
{
_asyncWaiters = new ConcurrentLinkedQueue <AsyncWaiter>();
}
}
}
AsyncWaiter waiter = new AsyncWaiter();
TaskCompletionSource <bool> task = new TaskCompletionSource <bool>();
waiter.Task = task;
if (duration != -1)
{
waiter.CancelDelay = new CancellationTokenSource();
waiter.Delay = Task.Delay(duration, waiter.CancelDelay.Token);
waiter.Delay.ContinueWith(new ActionContinuation(() => TimeoutAsync(waiter)));
}
if (token != CancellationToken.None)
{
waiter.CancelRegistration = token.Register(() => CancelAsync(waiter));
}
_asyncWaiters.Add(waiter);
VerboseLog("{0:000}|{1}|async wait enqued: {2:X}; {3}", Thread.CurrentThread.Id, _id, waiter.GetHashCode(), waiter.Task.Task.Id);
if (_wasDisposed || token.IsCancellationRequested || waiter.Delay != null && waiter.Delay.IsCompleted)
{
// Mitigate the above race where a finishing condition occured
// before where able to add our waiter to the waiters list.
if (_asyncWaiters.Remove(waiter))
{
CleanUpWaiter(waiter);
}
}
return(task.Task);
}
