| // Licensed to the Apache Software Foundation (ASF) under one |
| // or more contributor license agreements. See the NOTICE file |
| // distributed with this work for additional information |
| // regarding copyright ownership. The ASF licenses this file |
| // to you under the Apache License, Version 2.0 (the |
| // "License"); you may not use this file except in compliance |
| // with the License. You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, |
| // software distributed under the License is distributed on an |
| // "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| // KIND, either express or implied. See the License for the |
| // specific language governing permissions and limitations |
| // under the License. |
| |
| using System; |
| using System.Runtime.CompilerServices; |
| using System.Threading; |
| |
| namespace Org.Apache.REEF.Utilities.AsyncUtils |
| { |
| /// <summary> |
| /// This is to avoid deadlocks in clients that use synchronization context (WinForms/ASP.NET) |
| /// Use at asynchronous entry points of all async REEF client APIs. |
| /// |
| /// There is no need to use this in evaluator/driver. |
| /// </summary> |
| public struct RemoveSynchronizationContextAwaiter : INotifyCompletion |
| { |
| public bool IsCompleted |
| { |
| get { return SynchronizationContext.Current == null; } |
| } |
| |
| public void OnCompleted(Action continuation) |
| { |
| SynchronizationContext previousSynchronizationContext = SynchronizationContext.Current; |
| try |
| { |
| SynchronizationContext.SetSynchronizationContext(null); |
| continuation(); |
| } |
| finally |
| { |
| SynchronizationContext.SetSynchronizationContext(previousSynchronizationContext); |
| } |
| } |
| |
| public RemoveSynchronizationContextAwaiter GetAwaiter() |
| { |
| return this; |
| } |
| |
| public void GetResult() |
| { |
| } |
| } |
| } |