Moved FlutterDesktopMessenger to its own file.

Author: gaaclarke

shell/platform/windows/flutter_desktop_messenger.h

@@ -0,0 +1,78 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef FLUTTER_SHELL_PLATFORM_WINDOWS_FLUTTER_DESKTOP_MESSENGER_H_
+#define FLUTTER_SHELL_PLATFORM_WINDOWS_FLUTTER_DESKTOP_MESSENGER_H_
+
+#include <atomic>
+#include <mutex>
+
+#include "flutter/shell/platform/common/public/flutter_messenger.h"
+
+namespace flutter {
+
+class FlutterWindowsEngine;
+
+class FlutterDesktopMessenger {
+ public:
+  FlutterDesktopMessenger() = default;
+
+  /// Convert to FlutterDesktopMessengerRef.
+  FlutterDesktopMessengerRef ToRef() {
+    return reinterpret_cast<FlutterDesktopMessengerRef>(this);
+  }
+
+  /// Convert from FlutterDesktopMessengerRef.
+  static FlutterDesktopMessenger* FromRef(FlutterDesktopMessengerRef ref) {
+    return reinterpret_cast<FlutterDesktopMessenger*>(ref);
+  }
+
+  /// Getter for the engine field.
+  flutter::FlutterWindowsEngine* GetEngine() const { return engine; }
+
+  /// Setter for the engine field.
+  /// Thread-safe.
+  void SetEngine(flutter::FlutterWindowsEngine* arg_engine) {
+    std::scoped_lock lock(mutex_);
+    engine = arg_engine;
+  }
+
+  /// Increments the reference count.
+  ///
+  /// Thread-safe.
+  FlutterDesktopMessenger* AddRef() {
+    ref_count_.fetch_add(1);
+    return this;
+  }
+
+  /// Decrements the reference count and deletes the object if the count has
+  /// gone to zero.
+  ///
+  /// Thread-safe.
+  void Release() {
+    int32_t old_count = ref_count_.fetch_sub(1);
+    if (old_count <= 1) {
+      delete this;
+    }
+  }
+
+  /// Returns the mutex associated with the |FlutterDesktopMessenger|.
+  ///
+  /// This mutex is used to synchronize reading or writing state inside the
+  /// |FlutterDesktopMessenger| (ie |engine|).
+  std::mutex& GetMutex() { return mutex_; }
+
+  FlutterDesktopMessenger(const FlutterDesktopMessenger& value) = delete;
+  FlutterDesktopMessenger& operator=(const FlutterDesktopMessenger& value) =
+      delete;
+
+ private:
+  // The engine that owns this state object.
+  flutter::FlutterWindowsEngine* engine = nullptr;
+  std::mutex mutex_;
+  std::atomic<int32_t> ref_count_ = 0;
+};
+}  // namespace flutter
+
+#endif  // FLUTTER_SHELL_PLATFORM_WINDOWS_FLUTTER_WINDOW_STATE_H_

shell/platform/windows/flutter_windows.cc

@@ -262,8 +262,9 @@ bool FlutterDesktopMessengerSendWithReply(FlutterDesktopMessengerRef messenger,
                                           const size_t message_size,
                                           const FlutterDesktopBinaryReply reply,
                                           void* user_data) {
-  return messenger->GetEngine()->SendPlatformMessage(
-      channel, message, message_size, reply, user_data);
+  return flutter::FlutterDesktopMessenger::FromRef(messenger)
+      ->GetEngine()
+      ->SendPlatformMessage(channel, message, message_size, reply, user_data);
 }
 
 bool FlutterDesktopMessengerSend(FlutterDesktopMessengerRef messenger,
@@ -279,39 +280,45 @@ void FlutterDesktopMessengerSendResponse(
     const FlutterDesktopMessageResponseHandle* handle,
     const uint8_t* data,
     size_t data_length) {
-  messenger->GetEngine()->SendPlatformMessageResponse(handle, data,
-                                                      data_length);
+  flutter::FlutterDesktopMessenger::FromRef(messenger)
+      ->GetEngine()
+      ->SendPlatformMessageResponse(handle, data, data_length);
 }
 
 void FlutterDesktopMessengerSetCallback(FlutterDesktopMessengerRef messenger,
                                         const char* channel,
                                         FlutterDesktopMessageCallback callback,
                                         void* user_data) {
-  messenger->GetEngine()->message_dispatcher()->SetMessageCallback(
-      channel, callback, user_data);
+  flutter::FlutterDesktopMessenger::FromRef(messenger)
+      ->GetEngine()
+      ->message_dispatcher()
+      ->SetMessageCallback(channel, callback, user_data);
 }
 
 FlutterDesktopMessengerRef FlutterDesktopMessengerAddRef(
     FlutterDesktopMessengerRef messenger) {
-  return messenger->AddRef();
+  return flutter::FlutterDesktopMessenger::FromRef(messenger)
+      ->AddRef()
+      ->ToRef();
 }
 
 void FlutterDesktopMessengerRelease(FlutterDesktopMessengerRef messenger) {
-  messenger->Release();
+  flutter::FlutterDesktopMessenger::FromRef(messenger)->Release();
 }
 
 bool FlutterDesktopMessengerIsAvailable(FlutterDesktopMessengerRef messenger) {
-  return messenger->GetEngine() != nullptr;
+  return flutter::FlutterDesktopMessenger::FromRef(messenger)->GetEngine() !=
+         nullptr;
 }
 
 FlutterDesktopMessengerRef FlutterDesktopMessengerLock(
     FlutterDesktopMessengerRef messenger) {
-  messenger->GetMutex().lock();
+  flutter::FlutterDesktopMessenger::FromRef(messenger)->GetMutex().lock();
   return messenger;
 }
 
 void FlutterDesktopMessengerUnlock(FlutterDesktopMessengerRef messenger) {
-  messenger->GetMutex().unlock();
+  flutter::FlutterDesktopMessenger::FromRef(messenger)->GetMutex().unlock();
 }
 
 FlutterDesktopTextureRegistrarRef FlutterDesktopRegistrarGetTextureRegistrar(

shell/platform/windows/flutter_windows_engine.cc

@@ -185,9 +185,10 @@ FlutterWindowsEngine::FlutterWindowsEngine(
   plugin_registrar_ = std::make_unique<FlutterDesktopPluginRegistrar>();
   plugin_registrar_->engine = this;
 
-  messenger_wrapper_ = std::make_unique<BinaryMessengerImpl>(messenger_.get());
+  messenger_wrapper_ =
+      std::make_unique<BinaryMessengerImpl>(messenger_->ToRef());
   message_dispatcher_ =
-      std::make_unique<IncomingMessageDispatcher>(messenger_.get());
+      std::make_unique<IncomingMessageDispatcher>(messenger_->ToRef());
   message_dispatcher_->SetMessageCallback(
       kAccessibilityChannelName,
       [](FlutterDesktopMessengerRef messenger,

shell/platform/windows/flutter_windows_engine.h

@@ -20,6 +20,7 @@
 #include "flutter/shell/platform/common/incoming_message_dispatcher.h"
 #include "flutter/shell/platform/embedder/embedder.h"
 #include "flutter/shell/platform/windows/angle_surface_manager.h"
+#include "flutter/shell/platform/windows/flutter_desktop_messenger.h"
 #include "flutter/shell/platform/windows/flutter_project_bundle.h"
 #include "flutter/shell/platform/windows/flutter_windows_texture_registrar.h"
 #include "flutter/shell/platform/windows/public/flutter_windows.h"
@@ -124,7 +125,7 @@ class FlutterWindowsEngine {
   // Sets switches member to the given switches.
   void SetSwitches(const std::vector<std::string>& switches);
 
-  FlutterDesktopMessengerRef messenger() { return messenger_.get(); }
+  FlutterDesktopMessengerRef messenger() { return messenger_->ToRef(); }
 
   IncomingMessageDispatcher* message_dispatcher() {
     return message_dispatcher_.get();
@@ -283,7 +284,7 @@ class FlutterWindowsEngine {
   std::unique_ptr<TaskRunner> task_runner_;
 
   // The plugin messenger handle given to API clients.
-  fml::RefPtr<FlutterDesktopMessenger> messenger_;
+  fml::RefPtr<flutter::FlutterDesktopMessenger> messenger_;
 
   // A wrapper around messenger_ for interacting with client_wrapper-level APIs.
   std::unique_ptr<BinaryMessengerImpl> messenger_wrapper_;

shell/platform/windows/window_state.h

@@ -5,8 +5,6 @@
 #ifndef FLUTTER_SHELL_PLATFORM_WINDOWS_FLUTTER_WINDOW_STATE_H_
 #define FLUTTER_SHELL_PLATFORM_WINDOWS_FLUTTER_WINDOW_STATE_H_
 
-#include <mutex>
-
 #include "flutter/shell/platform/common/client_wrapper/include/flutter/plugin_registrar.h"
 #include "flutter/shell/platform/common/incoming_message_dispatcher.h"
 #include "flutter/shell/platform/embedder/embedder.h"
@@ -37,54 +35,6 @@ struct FlutterDesktopPluginRegistrar {
 
 // Wrapper to distinguish the messenger ref from the engine ref given out
 // in the C API.
-struct FlutterDesktopMessenger {
- public:
-  FlutterDesktopMessenger() = default;
-
-  /// Getter for the engine field.
-  flutter::FlutterWindowsEngine* GetEngine() const { return engine; }
-
-  /// Setter for the engine field.
-  /// Thread-safe.
-  void SetEngine(flutter::FlutterWindowsEngine* arg_engine) {
-    std::scoped_lock lock(mutex_);
-    engine = arg_engine;
-  }
-
-  /// Increments the reference count.
-  ///
-  /// Thread-safe.
-  FlutterDesktopMessenger* AddRef() {
-    ref_count_.fetch_add(1);
-    return this;
-  }
-
-  /// Decrements the reference count and deletes the object if the count has
-  /// gone to zero.
-  ///
-  /// Thread-safe.
-  void Release() {
-    int32_t old_count = ref_count_.fetch_sub(1);
-    if (old_count <= 1) {
-      delete this;
-    }
-  }
-
-  /// Returns the mutex associated with the |FlutterDesktopMessenger|.
-  ///
-  /// This mutex is used to synchronize reading or writing state inside the
-  /// |FlutterDesktopMessenger| (ie |engine|).
-  std::mutex& GetMutex() { return mutex_; }
-
-  FlutterDesktopMessenger(const FlutterDesktopMessenger& value) = delete;
-  FlutterDesktopMessenger& operator=(const FlutterDesktopMessenger& value) =
-      delete;
-
- private:
-  // The engine that owns this state object.
-  flutter::FlutterWindowsEngine* engine = nullptr;
-  std::mutex mutex_;
-  std::atomic<int32_t> ref_count_ = 0;
-};
+struct FlutterDesktopMessenger {};
 
 #endif  // FLUTTER_SHELL_PLATFORM_WINDOWS_FLUTTER_WINDOW_STATE_H_