#pragma warning disable CA1000 // Do not declare static members on generic types
/// <summary>
/// Gets the task created by this task completion source.
/// </summary>
#pragma warning disable CA1707 // Remove the underscores from member name
#pragma warning disable SA1300 // Element should begin with an uppercase letter
#pragma warning disable IDE1006 // Naming Styles
public static SystemTask get_Task(SystemTaskCompletionSource tcs)
{
var task = tcs.Task;
CoyoteRuntime.Current?.RegisterKnownControlledTask(task);
return(task);
}
/// <summary>
/// Wait for the next response
/// </summary>
/// <returns>The response from the server.</returns>
private async System.Threading.Tasks.Task <Response> Receive(int timeout)
{
System.Threading.Tasks.Task task = await System.Threading.Tasks.Task.WhenAny(
taskCompletion.Task,
System.Threading.Tasks.Task.Delay(timeout));
if (task != taskCompletion.Task)
{
taskCompletion = new System.Threading.Tasks.TaskCompletionSource <Response>();
// Timeout reached
throw new TimeoutException("Timeout when receiving message.");
}
if (task.Exception != null)
{
taskCompletion = new System.Threading.Tasks.TaskCompletionSource <Response>();
if (task.Exception.InnerException.InnerException != null)
{
throw task.Exception.InnerException.InnerException;
}
throw task.Exception;
}
var result = taskCompletion.Task.Result;
// Since we can't re-use the task completion, create a new one for the next message
taskCompletion = new System.Threading.Tasks.TaskCompletionSource <Response>();
return(result);
}
private async ValueTask<int> AwaitTcsAsValueTask(TaskCompletionSource<int> tcs)
=> await new ValueTask<int>(tcs.Task).ConfigureAwait(false);
private static Task CopyResultToCompletionSourceImplContinuation <TTask, TResult>(TTask task, TaskCompletionSource <TResult> tcs, Func <TTask, TResult> resultThunk)
where TTask : Task
{
return(task.ContinueWith(innerTask =>
{
switch (innerTask.Status)
{
case TaskStatus.Canceled:
case TaskStatus.Faulted:
TaskHelpers.TrySetFromTask(tcs, innerTask);
break;
case TaskStatus.RanToCompletion:
tcs.TrySetResult(resultThunk(task));
break;
}
}, TaskContinuationOptions.ExecuteSynchronously));
}
private static Task CopyResultToCompletionSourceImpl <TTask, TResult>(this TTask task, TaskCompletionSource <TResult> tcs, Func <TTask, TResult> resultThunk)
where TTask : Task
{
// Stay on the same thread if we can
if (task.IsCompleted)
{
switch (task.Status)
{
case TaskStatus.Canceled:
case TaskStatus.Faulted:
TaskHelpers.TrySetFromTask(tcs, task);
break;
case TaskStatus.RanToCompletion:
tcs.TrySetResult(resultThunk(task));
break;
}
return(TaskHelpers.Completed());
}
// Split into a continuation method so that we don't create a closure unnecessarily
return(CopyResultToCompletionSourceImplContinuation(task, tcs, resultThunk));
}
internal static Task CopyResultToCompletionSource <TResult>(this Task <TResult> task, TaskCompletionSource <TResult> tcs)
{
return(task.CopyResultToCompletionSourceImpl(tcs, innerTask => innerTask.Result));
}
/// <summary> /// Attempts to transition the underlying task into the <see cref="SystemTasks.TaskStatus.Canceled"/> state /// and enables a cancellation token to be stored in the canceled task. /// </summary> public static bool TrySetCanceled(SystemTaskCompletionSource tcs, SystemCancellationToken cancellationToken) => tcs.TrySetCanceled(cancellationToken);
/// <summary> /// Attempts to transition the underlying task into the <see cref="SystemTasks.TaskStatus.Faulted"/> state /// and binds a collection of exception objects to it. /// </summary> public static bool TrySetException(SystemTaskCompletionSource tcs, IEnumerable <Exception> exceptions) => tcs.TrySetException(exceptions);
/// <summary> /// Attempts to transition the underlying task into the <see cref="SystemTasks.TaskStatus.RanToCompletion"/> state. /// </summary> public static bool TrySetResult(SystemTaskCompletionSource tcs) => tcs.TrySetResult();
/// <summary> /// Attempts to transition the underlying task into the <see cref="SystemTasks.TaskStatus.Faulted"/> state /// and binds it to a specified exception. /// </summary> public static bool TrySetException(SystemTaskCompletionSource tcs, Exception exception) => tcs.TrySetException(exception);
/// <summary> /// Transitions the underlying task into the <see cref="SystemTasks.TaskStatus.Canceled"/> state. /// </summary> public static void SetCanceled(SystemTaskCompletionSource tcs) => tcs.SetCanceled();
/// <summary> /// Transitions the underlying task into the <see cref="SystemTasks.TaskStatus.Faulted"/> state /// and binds it to a specified exception. /// </summary> public static void SetException(SystemTaskCompletionSource tcs, Exception exception) => tcs.SetException(exception);
#pragma warning restore CA1707 // Remove the underscores from member name
#pragma warning restore SA1300 // Element should begin with an uppercase letter
#pragma warning restore IDE1006 // Naming Styles
/// <summary>
/// Transitions the underlying task into the <see cref="SystemTasks.TaskStatus.RanToCompletion"/> state.
/// </summary>
public static void SetResult(SystemTaskCompletionSource tcs) => tcs.SetResult();
public SimpleWorkQueue(Func <IChannelHandlerContext, TWork, Task> workerAsync)
{
_workerAsync = workerAsync;
_completionSource = new TaskCompletionSource();
_backlogQueue = new ConcurrentQueue <TWork>();
}
/// <summary> /// Attempts to transition the underlying task into the <see cref="SystemTasks.TaskStatus.Canceled"/> state. /// </summary> public static bool TrySetCanceled(SystemTaskCompletionSource tcs) => tcs.TrySetCanceled();
public static Task<TResult> FromResult<TResult> (TResult result)
{
var tcs = new TaskCompletionSource<TResult> ();
tcs.SetResult (result);
return tcs.Task;
}
/// <summary>
/// Asynchronously iterates through an enumerable of tasks.
/// </summary>
/// <param name="factory">The target factory.</param>
/// <param name="source">The enumerable containing the tasks to be iterated through.</param>
/// <param name="state">The asynchronous state for the returned Task.</param>
/// <param name="cancellationToken">The cancellation token used to cancel the iteration.</param>
/// <param name="creationOptions">Options that control the task's behavior.</param>
/// <param name="scheduler">The scheduler to which tasks will be scheduled.</param>
/// <returns>A Task that represents the complete asynchronous operation.</returns>
public static Task Iterate(this TaskFactory factory, IEnumerable <object> source, object state, CancellationToken cancellationToken, TaskCreationOptions creationOptions, TaskScheduler scheduler)
{
// Validate/update parameters
Contract.Requires(factory != null);
Contract.Requires(source != null);
Contract.Requires(scheduler != null);
// Get an enumerator from the enumerable
var enumerator = source.GetEnumerator();
if (enumerator == null)
{
throw new InvalidOperationException("Invalid enumerable - GetEnumerator returned null");
}
// Create the task to be returned to the caller. And ensure
// that when everything is done, the enumerator is cleaned up.
var trs = new TaskCompletionSource <object>(state, creationOptions);
trs.Task.ContinueWith(_ => enumerator.Dispose(), CancellationToken.None, TaskContinuationOptions.ExecuteSynchronously, TaskScheduler.Default);
// This will be called every time more work can be done.
Action <Task> recursiveBody = null;
recursiveBody = antecedent =>
{
try
{
// If we should continue iterating and there's more to iterate
// over, create a continuation to continue processing. We only
// want to continue processing once the current Task (as yielded
// from the enumerator) is complete.
if (enumerator.MoveNext())
{
var nextItem = enumerator.Current;
// If we got a Task, continue from it to continue iterating
if (nextItem is Task)
{
var nextTask = (Task)nextItem;
nextTask.IgnoreExceptions(); // TODO: Is this a good idea?
nextTask.ContinueWith(recursiveBody).IgnoreExceptions();
}
//// If we got a scheduler, continue iterating under the new scheduler,
//// enabling hopping between contexts.
else if (nextItem is TaskScheduler)
{
Task.Factory.StartNew(() => recursiveBody(null), CancellationToken.None, TaskCreationOptions.None, (TaskScheduler)nextItem).IgnoreExceptions();
}
//// Anything else is invalid
else
{
trs.TrySetException(new InvalidOperationException("Task or TaskScheduler object expected in Iterate"));
}
}
//// Otherwise, we're done!
else
{
trs.TrySetResult(null);
}
}
//// If MoveNext throws an exception, propagate that to the user,
//// either as cancellation or as a fault
catch (Exception exc)
{
var oce = exc as OperationCanceledException;
if (oce != null && oce.CancellationToken == cancellationToken)
{
trs.TrySetCanceled();
}
else
{
trs.TrySetException(exc);
}
}
};
// Get things started by launching the first task
factory.StartNew(() => recursiveBody(null), CancellationToken.None, TaskCreationOptions.None, scheduler).IgnoreExceptions();
// Return the representative task to the user
return(trs.Task);
}
