Initial commit of SqlTools Service API

ServiceHost/Utility/ThreadSynchronizationContext.cs

@@ -0,0 +1,77 @@
+//
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+//
+
+using System;
+using System.Collections.Concurrent;
+using System.Threading;
+
+namespace Microsoft.PowerShell.EditorServices.Utility
+{
+    /// <summary>
+    /// Provides a SynchronizationContext implementation that can be used
+    /// in console applications or any thread which doesn't have its
+    /// own SynchronizationContext.
+    /// </summary>
+    public class ThreadSynchronizationContext : SynchronizationContext
+    {
+        #region Private Fields
+
+        private BlockingCollection<Tuple<SendOrPostCallback, object>> requestQueue =
+            new BlockingCollection<Tuple<SendOrPostCallback, object>>();
+
+        #endregion
+
+        #region Constructors
+
+        /// <summary>
+        /// Posts a request for execution to the SynchronizationContext.
+        /// This will be executed on the SynchronizationContext's thread.
+        /// </summary>
+        /// <param name="callback">
+        /// The callback to be invoked on the SynchronizationContext's thread.
+        /// </param>
+        /// <param name="state">
+        /// A state object to pass along to the callback when executed through
+        /// the SynchronizationContext.
+        /// </param>
+        public override void Post(SendOrPostCallback callback, object state)
+        {
+            // Add the request to the queue
+            this.requestQueue.Add(
+                new Tuple<SendOrPostCallback, object>(
+                    callback, state));
+        }
+
+        #endregion
+
+        #region Public Methods
+
+        /// <summary>
+        /// Starts the SynchronizationContext message loop on the current thread.
+        /// </summary>
+        public void RunLoopOnCurrentThread()
+        {
+            Tuple<SendOrPostCallback, object> request;
+
+            while (this.requestQueue.TryTake(out request, Timeout.Infinite))
+            {
+                // Invoke the request's callback
+                request.Item1(request.Item2);
+            }
+        }
+
+        /// <summary>
+        /// Ends the SynchronizationContext message loop.
+        /// </summary>
+        public void EndLoop()
+        {
+            // Tell the blocking queue that we're done
+            this.requestQueue.CompleteAdding();
+        }
+
+        #endregion
+    }
+}
+