| /* |
| * Copyright 2004 The WebRTC Project Authors. All rights reserved. |
| * |
| * Use of this source code is governed by a BSD-style license |
| * that can be found in the LICENSE file in the root of the source |
| * tree. An additional intellectual property rights grant can be found |
| * in the file PATENTS. All contributing project authors may |
| * be found in the AUTHORS file in the root of the source tree. |
| */ |
| |
| #ifndef WEBRTC_BASE_MESSAGEHANDLER_H_ |
| #define WEBRTC_BASE_MESSAGEHANDLER_H_ |
| |
| #include <memory> |
| #include <utility> |
| |
| #include "webrtc/base/constructormagic.h" |
| |
| namespace rtc { |
| |
| struct Message; |
| |
| // Messages get dispatched to a MessageHandler |
| |
| class MessageHandler { |
| public: |
| virtual ~MessageHandler(); |
| virtual void OnMessage(Message* msg) = 0; |
| |
| protected: |
| MessageHandler() {} |
| |
| private: |
| RTC_DISALLOW_COPY_AND_ASSIGN(MessageHandler); |
| }; |
| |
| // Helper class to facilitate executing a functor on a thread. |
| template <class ReturnT, class FunctorT> |
| class FunctorMessageHandler : public MessageHandler { |
| public: |
| explicit FunctorMessageHandler(const FunctorT& functor) |
| : functor_(functor) {} |
| virtual void OnMessage(Message* msg) { |
| result_ = functor_(); |
| } |
| const ReturnT& result() const { return result_; } |
| |
| private: |
| FunctorT functor_; |
| ReturnT result_; |
| }; |
| |
| // Specialization for std::unique_ptr<ReturnT>. |
| template <class ReturnT, class FunctorT> |
| class FunctorMessageHandler<class std::unique_ptr<ReturnT>, FunctorT> |
| : public MessageHandler { |
| public: |
| explicit FunctorMessageHandler(const FunctorT& functor) : functor_(functor) {} |
| virtual void OnMessage(Message* msg) { result_ = std::move(functor_()); } |
| std::unique_ptr<ReturnT> result() { return std::move(result_); } |
| |
| private: |
| FunctorT functor_; |
| std::unique_ptr<ReturnT> result_; |
| }; |
| |
| // Specialization for ReturnT of void. |
| template <class FunctorT> |
| class FunctorMessageHandler<void, FunctorT> : public MessageHandler { |
| public: |
| explicit FunctorMessageHandler(const FunctorT& functor) |
| : functor_(functor) {} |
| virtual void OnMessage(Message* msg) { |
| functor_(); |
| } |
| void result() const {} |
| |
| private: |
| FunctorT functor_; |
| }; |
| |
| } // namespace rtc |
| |
| #endif // WEBRTC_BASE_MESSAGEHANDLER_H_ |