internal EventLoopScheduler(Func <ThreadStart, Thread> threadFactory)
{
#endif
this.threadFactory = threadFactory ?? throw new ArgumentNullException(nameof(threadFactory));
stopwatch = ConcurrencyAbstraction.Current.StartStopwatch();
gate = new object();
_evt = new SemaphoreSlim(0);
queue = new SchedulerQueue <TimeSpan>();
readyList = new Queue <ScheduledItem <TimeSpan> >();
ExitIfEmpty = false;
}
public static void Run(SchedulerQueue <TimeSpan> queue)
{
while (0 < queue.Count)
{
var item = queue.Dequeue();
if (item.IsCanceled)
{
continue;
}
var wait = item.DueTime - Time;
if (wait.Ticks > 0)
{
ConcurrencyAbstraction.Current.Sleep(wait);
}
if (false == item.IsCanceled)
{
item.Invoke();
}
}
}
/// <summary>
/// Schedules an action to be executed after dueTime.
/// </summary>
/// <typeparam name="TState">The type of the state passed to the scheduled action.</typeparam>
/// <param name="state">State passed to the action to be executed.</param>
/// <param name="action">Action to be executed.</param>
/// <param name="dueTime">Relative time after which to execute the action.</param>
/// <returns>The disposable object used to cancel the scheduled action (best effort).</returns>
/// <exception cref="ArgumentNullException"><paramref name="action"/> is <c>null</c>.</exception>
public override IDisposable Schedule <TState>(TState state, TimeSpan dueTime, Func <IScheduler, TState, IDisposable> action)
{
if (null == action)
{
throw new ArgumentNullException(nameof(action));
}
SchedulerQueue <TimeSpan> queue;
// There is no timed task and no task is currently running
if (false == running)
{
running = true;
if (TimeSpan.Zero < dueTime)
{
ConcurrencyAbstraction.Current.Sleep(dueTime);
}
// execute directly without queueing
IDisposable disposable;
try
{
disposable = action(this, state);
}
catch
{
SetQueue(null);
running = false;
throw;
}
// did recursive tasks arrive?
queue = GetQueue();
// yes, run those in the queue as well
if (null != queue)
{
try
{
Trampoline.Run(queue);
}
finally
{
SetQueue(null);
running = false;
}
}
else
{
running = false;
}
return(disposable);
}
queue = GetQueue();
// if there is a task running or there is a queue
if (null == queue)
{
queue = new SchedulerQueue <TimeSpan>(4);
SetQueue(queue);
}
var dt = Time + Scheduler.Normalize(dueTime);
// queue up more work
var si = new ScheduledItem <TimeSpan, TState>(this, state, action, dt);
queue.Enqueue(si);
return(si);
}
private static void SetQueue(SchedulerQueue <TimeSpan> newQueue) => threadLocalQueue = newQueue;