Async flow control

projects/Directory.Packages.props

@@ -34,6 +34,7 @@
     <PackageVersion Include="System.Threading.Channels" Version="6.0.0" />
     <PackageVersion Include="System.Text.Json" Version="6.0.0" />
     <PackageVersion Include="System.Net.Http.Json" Version="6.0.0" />
+    <PackageVersion Include="Microsoft.Bcl.AsyncInterfaces" Version="6.0.0" />
   </ItemGroup>
   <ItemGroup Condition="$(TargetFramework)=='net472'">
     <PackageVersion Include="System.Text.Json" Version="6.0.0" />
@@ -46,4 +47,4 @@
     <GlobalPackageReference Include="Microsoft.SourceLink.GitHub" Version="8.0.0" />
     <GlobalPackageReference Include="MinVer" Version="5.0.0" />
   </ItemGroup>
-</Project>
+</Project>

projects/RabbitMQ.Client/RabbitMQ.Client.csproj

@@ -77,5 +77,6 @@
     <PackageReference Include="System.Diagnostics.DiagnosticSource" />
     <PackageReference Include="System.Memory" />
     <PackageReference Include="System.Threading.Channels" />
+    <PackageReference Include="Microsoft.Bcl.AsyncInterfaces" />
   </ItemGroup>
 </Project>

projects/RabbitMQ.Client/client/framing/Channel.cs

@@ -47,21 +47,21 @@ public override ValueTask BasicAckAsync(ulong deliveryTag, bool multiple,
             CancellationToken cancellationToken)
         {
             var method = new BasicAck(deliveryTag, multiple);
-            return ModelSendAsync(method, cancellationToken);
+            return ModelSendAsync(in method, cancellationToken);
         }
 
         public override ValueTask BasicNackAsync(ulong deliveryTag, bool multiple, bool requeue,
             CancellationToken cancellationToken)
         {
             var method = new BasicNack(deliveryTag, multiple, requeue);
-            return ModelSendAsync(method, cancellationToken);
+            return ModelSendAsync(in method, cancellationToken);
         }
 
         public override ValueTask BasicRejectAsync(ulong deliveryTag, bool requeue,
             CancellationToken cancellationToken)
         {
             var method = new BasicReject(deliveryTag, requeue);
-            return ModelSendAsync(method, cancellationToken);
+            return ModelSendAsync(in method, cancellationToken);
         }
 
         /// <summary>

projects/RabbitMQ.Client/client/impl/AsyncManualResetEvent.cs

@@ -0,0 +1,155 @@
+// This source code is dual-licensed under the Apache License, version
+// 2.0, and the Mozilla Public License, version 2.0.
+//
+// The APL v2.0:
+//
+//---------------------------------------------------------------------------
+//   Copyright (c) 2007-2024 Broadcom. All Rights Reserved.
+//
+//   Licensed 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
+//
+//       https://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.
+//---------------------------------------------------------------------------
+//
+// The MPL v2.0:
+//
+//---------------------------------------------------------------------------
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at https://mozilla.org/MPL/2.0/.
+//
+//  Copyright (c) 2007-2024 Broadcom. All Rights Reserved.
+//---------------------------------------------------------------------------
+
+using System;
+using System.Diagnostics.CodeAnalysis;
+using System.Threading;
+using System.Threading.Tasks;
+using System.Threading.Tasks.Sources;
+
+namespace RabbitMQ.Client.client.impl
+{
+    sealed class AsyncManualResetEvent : IValueTaskSource
+    {
+        private ManualResetValueTaskSourceCore<bool> _valueTaskSource;
+        private bool _isSet;
+
+        public AsyncManualResetEvent(bool initialState = false)
+        {
+            _isSet = initialState;
+            _valueTaskSource.Reset();
+            if (initialState)
+            {
+                _valueTaskSource.SetResult(true);
+            }
+        }
+
+        public bool IsSet => Volatile.Read(ref _isSet);
+
+        public async ValueTask WaitAsync(CancellationToken cancellationToken)
+        {
+            if (IsSet)
+            {
+                return;
+            }
+
+            cancellationToken.ThrowIfCancellationRequested();
+
+            CancellationTokenRegistration tokenRegistration =
+#if NET6_0_OR_GREATER
+                cancellationToken.UnsafeRegister(
+                    static state =>
+                    {
+                        var (source, token) = ((ManualResetValueTaskSourceCore<bool>, CancellationToken))state!;
+                        source.SetException(new OperationCanceledException(token));
+                    }, (_valueTaskSource, cancellationToken));
+#else
+                cancellationToken.Register(
+                    static state =>
+                    {
+                        var (source, token) = ((ManualResetValueTaskSourceCore<bool>, CancellationToken))state!;
+                        source.SetException(new OperationCanceledException(token));
+                    },
+                    state: (_valueTaskSource, cancellationToken), useSynchronizationContext: false);
+#endif
+            try
+            {
+                await new ValueTask(this, _valueTaskSource.Version)
+                    .ConfigureAwait(false);
+            }
+            finally
+            {
+#if NET6_0_OR_GREATER
+                await tokenRegistration.DisposeAsync()
+                    .ConfigureAwait(false);
+#else
+                tokenRegistration.Dispose();
+#endif
+            }
+        }
+
+        public void Set()
+        {
+            if (IsSet)
+            {
+                return;
+            }
+
+            Volatile.Write(ref _isSet, true);
+            _valueTaskSource.SetResult(true);
+        }
+
+        public void Reset()
+        {
+            if (!IsSet)
+            {
+                return;
+            }
+
+            Volatile.Write(ref _isSet, false);
+            _valueTaskSource.Reset();
+        }
+
+        void IValueTaskSource.GetResult(short token)
+        {
+            if (token != _valueTaskSource.Version)
+            {
+                ThrowIncorrectTokenException();
+            }
+
+            _valueTaskSource.GetResult(token);
+        }
+
+        ValueTaskSourceStatus IValueTaskSource.GetStatus(short token)
+        {
+            if (token != _valueTaskSource.Version)
+            {
+                ThrowIncorrectTokenException();
+            }
+
+            return _valueTaskSource.GetStatus(token);
+        }
+
+        void IValueTaskSource.OnCompleted(Action<object?> continuation, object? state, short token, ValueTaskSourceOnCompletedFlags flags)
+        {
+            if (token != _valueTaskSource.Version)
+            {
+                ThrowIncorrectTokenException();
+            }
+
+            _valueTaskSource.OnCompleted(continuation, state, token, flags);
+        }
+
+        [DoesNotReturn]
+        static void ThrowIncorrectTokenException() =>
+            throw new InvalidOperationException("ValueTask cannot be awaited multiple times.");
+    }
+}