public Registration () {
Scope = CancellationScope.Current;
Scheduler = TaskScheduler.Current;
if (Scheduler == null)
throw new InvalidOperationException("No implicitly active TaskScheduler on this thread.");
}
public Registration()
{
Scope = CancellationScope.Current;
Scheduler = TaskScheduler.Current;
if (Scheduler == null)
{
throw new InvalidOperationException("No implicitly active TaskScheduler on this thread.");
}
}
private void AddChild(CancellationScope child)
{
if (this == Null)
{
return;
}
if (Children == null)
{
Children = new UnorderedList <CancellationScope>();
}
Children.Add(child);
}
public static bool TryCancelScope(this tTask task)
{
if (task.IsCanceled)
{
return(true);
}
else if (task.IsCompleted)
{
return(false);
}
CancellationScope scope;
if (CancellationScope.TryGet(task, out scope))
{
return(scope.TryCancel());
}
return(false);
}
public void OnCompleted(Action continuation)
{
CancellationUtil.UnpackContinuation(continuation, out Scope.Task);
CancellationScope existingScope;
if (CancellationScope.TryGet(Scope.Task, out existingScope))
{
// HACK: In some cases a cancelled task will get resumed, which starts it over from the beginning.
// This hits us and we will get asked to schedule a resume, but we should ignore it so that the task
// stays dead as it should.
#if TRACING
Console.WriteLine("Rejecting attempted resurrection of task {0}", existingScope);
#endif
return;
}
CancellationScope.Set(Scope.Task, Scope);
IsCompleted = true;
continuation();
}
public CancellationScopeAwaiter (CancellationScope scope)
: this()
{
Scope = scope;
IsCompleted = false;
}
private void AddChild (CancellationScope child) {
if (this == Null)
return;
if (Children == null)
Children = new UnorderedList<CancellationScope>();
Children.Add(child);
}
public static bool TryGet (tTask task, out CancellationScope result) {
return ScopeRegistry.TryGetValue(task, out result);
}
public static void Set (tTask task, CancellationScope scope) {
ScopeRegistry.Add(task, scope);
}
public CancellationScopeAwaiter(CancellationScope scope)
: this()
{
Scope = scope;
IsCompleted = false;
}
public static bool TryGet(tTask task, out CancellationScope result)
{
return(ScopeRegistry.TryGetValue(task, out result));
}
public static void Set(tTask task, CancellationScope scope)
{
ScopeRegistry.Add(task, scope);
}