public void Dispatch()
{
IQueueReader reader = null;
Item item = new Item();
IQueueReader[] outstandingReaders = null;
IQueueWaiter[] waiters = null;
bool itemAvailable = true;
lock (ThisLock)
{
itemAvailable = !((queueState == QueueState.Closed) || (queueState == QueueState.Shutdown));
GetWaiters(out waiters);
if (queueState != QueueState.Closed)
{
itemQueue.MakePendingItemAvailable();
if (readerQueue.Count > 0)
{
item = itemQueue.DequeueAvailableItem();
reader = readerQueue.Dequeue();
if (queueState == QueueState.Shutdown && readerQueue.Count > 0 && itemQueue.ItemCount == 0)
{
outstandingReaders = new IQueueReader[readerQueue.Count];
readerQueue.CopyTo(outstandingReaders, 0);
readerQueue.Clear();
itemAvailable = false;
}
}
}
}
if (outstandingReaders != null)
{
if (completeOutstandingReadersCallback == null)
{
completeOutstandingReadersCallback = CompleteOutstandingReadersCallback;
}
ActionItem.Schedule(completeOutstandingReadersCallback, outstandingReaders);
}
if (waiters != null)
{
CompleteWaitersLater(itemAvailable, waiters);
}
if (reader != null)
{
InvokeDequeuedCallback(item.DequeuedCallback);
reader.Set(item);
}
}
static void InvokeDequeuedCallbackLater(Action dequeuedCallback)
{
if (dequeuedCallback != null)
{
if (onInvokeDequeuedCallback == null)
{
onInvokeDequeuedCallback = OnInvokeDequeuedCallback;
}
ActionItem.Schedule(onInvokeDequeuedCallback, dequeuedCallback);
}
}
void ScheduleElapsedTimers(TimerGroup timerGroup, long now)
{
TimerQueue timerQueue = timerGroup.TimerQueue;
while (timerQueue.Count > 0)
{
IOThreadTimer timer = timerQueue.MinTimer;
long timeDiff = timer.dueTime - now;
if (timeDiff <= timer.maxSkew)
{
timerQueue.DeleteMinTimer();
ActionItem.Schedule(timer.callback, timer.callbackState);
}
else
{
break;
}
}
}
internal void OnTimer()
{
_timerFiredCallback(_timerFiredState);
lock (_cancellationTokenSources)
{
_timerFired = true;
}
// Once _timerFired is set, there's no need to hold the lock as
// no more will be added to the list.
foreach (CancellationTokenSource cts in _cancellationTokenSources)
{
// TODO: ActionItem.Schedule might be overkill here as I don't expect there
// to be many cancellations. There's just no
if (!cts.IsCancellationRequested)
{
ActionItem.Schedule(CancelTokenSource, cts);
}
}
}
static void CompleteWaitersLater(bool itemAvailable, IQueueWaiter[] waiters)
{
if (itemAvailable)
{
if (completeWaitersTrueCallback == null)
{
completeWaitersTrueCallback = CompleteWaitersTrueCallback;
}
ActionItem.Schedule(completeWaitersTrueCallback, waiters);
}
else
{
if (completeWaitersFalseCallback == null)
{
completeWaitersFalseCallback = CompleteWaitersFalseCallback;
}
ActionItem.Schedule(completeWaitersFalseCallback, waiters);
}
}
void ScheduleWait()
{
ActionItem.Schedule(onWaitCallback, null);
waitScheduled = true;
}
private void ScheduleWait()
{
ActionItem.Schedule(_onWaitCallback, null);
_waitScheduled = true;
}
void EnqueueAndDispatch(Item item, bool canDispatchOnThisThread)
{
bool disposeItem = false;
IQueueReader reader = null;
bool dispatchLater = false;
IQueueWaiter[] waiters = null;
bool itemAvailable = true;
lock (ThisLock)
{
itemAvailable = !((queueState == QueueState.Closed) || (queueState == QueueState.Shutdown));
GetWaiters(out waiters);
if (queueState == QueueState.Open)
{
if (canDispatchOnThisThread)
{
if (readerQueue.Count == 0)
{
itemQueue.EnqueueAvailableItem(item);
}
else
{
reader = readerQueue.Dequeue();
}
}
else
{
if (readerQueue.Count == 0)
{
itemQueue.EnqueueAvailableItem(item);
}
else
{
itemQueue.EnqueuePendingItem(item);
dispatchLater = true;
}
}
}
else // queueState == QueueState.Closed || queueState == QueueState.Shutdown
{
disposeItem = true;
}
}
if (waiters != null)
{
if (canDispatchOnThisThread)
{
CompleteWaiters(itemAvailable, waiters);
}
else
{
CompleteWaitersLater(itemAvailable, waiters);
}
}
if (reader != null)
{
InvokeDequeuedCallback(item.DequeuedCallback);
reader.Set(item);
}
if (dispatchLater)
{
if (onDispatchCallback == null)
{
onDispatchCallback = OnDispatchCallback;
}
ActionItem.Schedule(onDispatchCallback, this);
}
else if (disposeItem)
{
InvokeDequeuedCallback(item.DequeuedCallback);
DisposeItem(item);
}
}