1 files changed, 56 insertions, 54 deletions

diff --git a/src/csharp/Grpc.Core/GrpcEnvironment.cs b/src/csharp/Grpc.Core/GrpcEnvironment.cs
index 30ff289714..47d1651aab 100644
--- a/src/csharp/Grpc.Core/GrpcEnvironment.cs
+++ b/src/csharp/Grpc.Core/GrpcEnvironment.cs
@@ -33,7 +33,9 @@
 
 using System;
 using System.Runtime.InteropServices;
+using System.Threading.Tasks;
 using Grpc.Core.Internal;
+using Grpc.Core.Utils;
 
 namespace Grpc.Core
 {
@@ -51,20 +53,18 @@ namespace Grpc.Core
         static extern void grpcsharp_shutdown();
 
         static object staticLock = new object();
-        static volatile GrpcEnvironment instance;
+        static GrpcEnvironment instance;
 
         readonly GrpcThreadPool threadPool;
         readonly CompletionRegistry completionRegistry;
+        readonly DebugStats debugStats = new DebugStats();
         bool isClosed;
 
         /// <summary>
-        /// Makes sure GRPC environment is initialized. Subsequent invocations don't have any
-        /// effect unless you call Shutdown first.
-        /// Although normal use cases assume you will call this just once in your application's
-        /// lifetime (and call Shutdown once you're done), for the sake of easier testing it's
-        /// allowed to initialize the environment again after it has been successfully shutdown.
+        /// Returns an instance of initialized gRPC environment.
+        /// Subsequent invocations return the same instance unless Shutdown has been called first.
         /// </summary>
-        public static void Initialize()
+        internal static GrpcEnvironment GetInstance()
         {
             lock (staticLock)
             {
@@ -72,12 +72,13 @@ namespace Grpc.Core
                 {
                     instance = new GrpcEnvironment();
                 }
+                return instance;
             }
         }
 
         /// <summary>
-        /// Shuts down the GRPC environment if it was initialized before.
-        /// Repeated invocations have no effect.
+        /// Shuts down the gRPC environment if it was initialized before.
+        /// Blocks until the environment has been fully shutdown.
         /// </summary>
         public static void Shutdown()
         {
@@ -87,50 +88,55 @@ namespace Grpc.Core
                 {
                     instance.Close();
                     instance = null;
-
-                    CheckDebugStats();
                 }
             }
         }
 
-        internal static GrpcThreadPool ThreadPool
+        /// <summary>
+        /// Creates gRPC environment.
+        /// </summary>
+        private GrpcEnvironment()
+        {
+            GrpcLog.RedirectNativeLogs(Console.Error);
+            grpcsharp_init();
+            completionRegistry = new CompletionRegistry(this);
+            threadPool = new GrpcThreadPool(this, THREAD_POOL_SIZE);
+            threadPool.Start();
+            // TODO: use proper logging here
+            Console.WriteLine("GRPC initialized.");
+        }
+
+        /// <summary>
+        /// Gets the completion registry used by this gRPC environment.
+        /// </summary>
+        internal CompletionRegistry CompletionRegistry
         {
             get
             {
-                var inst = instance;
-                if (inst == null)
-                {
-                    throw new InvalidOperationException("GRPC environment not initialized");
-                }
-                return inst.threadPool;
+                return this.completionRegistry;
             }
         }
 
-        internal static CompletionRegistry CompletionRegistry
+        /// <summary>
+        /// Gets the completion queue used by this gRPC environment.
+        /// </summary>
+        internal CompletionQueueSafeHandle CompletionQueue
         {
             get
             {
-                var inst = instance;
-                if (inst == null)
-                {
-                    throw new InvalidOperationException("GRPC environment not initialized");
-                }
-                return inst.completionRegistry;
+                return this.threadPool.CompletionQueue;
             }
         }
 
         /// <summary>
-        /// Creates gRPC environment.
+        /// Gets the completion queue used by this gRPC environment.
         /// </summary>
-        private GrpcEnvironment()
+        internal DebugStats DebugStats
         {
-            GrpcLog.RedirectNativeLogs(Console.Error);
-            grpcsharp_init();
-            completionRegistry = new CompletionRegistry();
-            threadPool = new GrpcThreadPool(THREAD_POOL_SIZE);
-            threadPool.Start();
-            // TODO: use proper logging here
-            Console.WriteLine("GRPC initialized.");
+            get
+            {
+                return this.debugStats;
+            }
         }
 
         /// <summary>
@@ -146,32 +152,28 @@ namespace Grpc.Core
             grpcsharp_shutdown();
             isClosed = true;
 
+            debugStats.CheckOK();
+
             // TODO: use proper logging here
             Console.WriteLine("GRPC shutdown.");
         }
 
-        private static void CheckDebugStats()
+        /// <summary>
+        /// Shuts down this environment asynchronously.
+        /// </summary>
+        private Task CloseAsync()
         {
-            var remainingClientCalls = DebugStats.ActiveClientCalls.Count;
-            if (remainingClientCalls != 0)
-            {                
-                DebugWarning(string.Format("Detected {0} client calls that weren't disposed properly.", remainingClientCalls));
-            }
-            var remainingServerCalls = DebugStats.ActiveServerCalls.Count;
-            if (remainingServerCalls != 0)
-            {
-                DebugWarning(string.Format("Detected {0} server calls that weren't disposed properly.", remainingServerCalls));
-            }
-            var pendingBatchCompletions = DebugStats.PendingBatchCompletions.Count;
-            if (pendingBatchCompletions != 0)
+            return Task.Run(() =>
             {
-                DebugWarning(string.Format("Detected {0} pending batch completions.", pendingBatchCompletions));
-            }
-        }
-
-        private static void DebugWarning(string message)
-        {
-            throw new Exception("Shutdown check: " + message);
+                try
+                {
+                    Close();
+                }
+                catch (Exception e)
+                {
+                    Console.WriteLine("Error occured while shutting down GrpcEnvironment: " + e);
+                }
+            });
         }
     }
 }