Initial checkin of gRPC to third_party/

third_party/grpc/src/csharp/Grpc.Core/Internal/AsyncCompletion.cs

 #region Copyright notice and license
-// Protocol Buffers - Google's data interchange format
-// Copyright 2008 Google Inc.  All rights reserved.
-// https://developers.google.com/protocol-buffers/
-//
+
+// Copyright 2015-2016, Google Inc.
+// All rights reserved.
+// 
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
-//
+// 
 //     * Redistributions of source code must retain the above copyright
 // notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 // copyright notice, this list of conditions and the following disclaimer
 // in the documentation and/or other materials provided with the
 // distribution.
 //     * Neither the name of Google Inc. nor the names of its
 // contributors may be used to endorse or promote products derived from
 // this software without specific prior written permission.
-//
+// 
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
 #endregion
 
 using System;
-using System.IO;
+using System.Diagnostics;
+using System.Runtime.CompilerServices;
+using System.Runtime.InteropServices;
+using System.Threading;
+using System.Threading.Tasks;
+using Grpc.Core.Internal;
+using Grpc.Core.Utils;
 
-namespace Google.Protobuf.ProtoDump
+namespace Grpc.Core.Internal
 {
     /// <summary>
-    /// Small utility to load a binary message and dump it in JSON format.
+    /// If error != null, there's been an error or operation has been cancelled.
     /// </summary>
-    internal class Program
+    internal delegate void AsyncCompletionDelegate<T>(T result, Exception error);
+
+    /// <summary>
+    /// Helper for transforming AsyncCompletionDelegate into full-fledged Task.
+    /// </summary>
+    internal class AsyncCompletionTaskSource<T>
     {
-        private static int Main(string[] args)
+        readonly TaskCompletionSource<T> tcs = new TaskCompletionSource<T>();
+        readonly AsyncCompletionDelegate<T> completionDelegate;
+
+        public AsyncCompletionTaskSource()
         {
-            if (args.Length != 2)
+            completionDelegate = new AsyncCompletionDelegate<T>(HandleCompletion);
+        }
+
+        public Task<T> Task
+        {
+            get
             {
-                Console.Error.WriteLine("Usage: Google.Protobuf.JsonDump <descriptor type name> <input data>");
-                Console.Error.WriteLine("The descriptor type name is the fully-qualified message name,");
-                Console.Error.WriteLine("including assembly e.g. ProjectNamespace.Message,Company.Project");
-                return 1;
+                return tcs.Task;
             }
-            Type type = Type.GetType(args[0]);
-            if (type == null)
+        }
+
+        public AsyncCompletionDelegate<T> CompletionDelegate
+        {
+            get
             {
-                Console.Error.WriteLine("Unable to load type {0}.", args[0]);
-                return 1;
+                return completionDelegate;
             }
-            if (!typeof(IMessage).IsAssignableFrom(type))
+        }
+
+        private void HandleCompletion(T value, Exception error)
+        {
+            if (error == null)
             {
-                Console.Error.WriteLine("Type {0} doesn't implement IMessage.", args[0]);
-                return 1;
+                tcs.SetResult(value);
+                return;
             }
-            IMessage message = (IMessage) Activator.CreateInstance(type);
-            using (var input = File.OpenRead(args[1]))
+            if (error is OperationCanceledException)
             {
-                message.MergeFrom(input);
+                tcs.SetCanceled();
+                return;
             }
-            Console.WriteLine(message);
-            return 0;
+            tcs.SetException(error);
         }
     }
-}
+}