5 // Marek Safar <marek.safar@gmail.com>
7 // Copyright (C) 2011 Novell, Inc (http://www.novell.com)
8 // Copyright (C) 2011 Xamarin, Inc (http://www.xamarin.com)
10 // Permission is hereby granted, free of charge, to any person obtaining
11 // a copy of this software and associated documentation files (the
12 // "Software"), to deal in the Software without restriction, including
13 // without limitation the rights to use, copy, modify, merge, publish,
14 // distribute, sublicense, and/or sell copies of the Software, and to
15 // permit persons to whom the Software is furnished to do so, subject to
16 // the following conditions:
18 // The above copyright notice and this permission notice shall be
19 // included in all copies or substantial portions of the Software.
21 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
22 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
23 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
24 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
25 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
26 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
27 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
32 using System.Threading;
33 using System.Threading.Tasks;
34 using System.Runtime.ExceptionServices;
36 namespace System.Runtime.CompilerServices
38 public struct TaskAwaiter<TResult> : ICriticalNotifyCompletion
40 readonly Task<TResult> task;
42 internal TaskAwaiter (Task<TResult> task)
47 public bool IsCompleted {
49 return task.IsCompleted;
53 public TResult GetResult ()
55 if (!task.IsCompleted)
56 task.WaitCore (Timeout.Infinite, CancellationToken.None, true);
58 if (task.Status != TaskStatus.RanToCompletion)
59 ExceptionDispatchInfo.Capture (TaskAwaiter.HandleUnexpectedTaskResult (task)).Throw ();
64 public void OnCompleted (Action continuation)
66 if (continuation == null)
67 throw new ArgumentNullException ("continuation");
69 TaskAwaiter.HandleOnCompleted (task, continuation, true, true);
72 public void UnsafeOnCompleted (Action continuation)
74 if (continuation == null)
75 throw new ArgumentNullException ("continuation");
77 TaskAwaiter.HandleOnCompleted (task, continuation, true, false);