| // Copyright 2020 Google LLC |
| // |
| // 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. |
| |
| #ifndef _CORE_INTERNAL_MEDIUMS_WEBRTC_WEBRTC_SOCKET_H_ |
| #define _CORE_INTERNAL_MEDIUMS_WEBRTC_WEBRTC_SOCKET_H_ |
| |
| #include <memory> |
| |
| #include "core/listeners.h" |
| #include "platform/base/input_stream.h" |
| #include "platform/base/output_stream.h" |
| #include "platform/base/socket.h" |
| #include "platform/public/atomic_boolean.h" |
| #include "platform/public/condition_variable.h" |
| #include "platform/public/mutex.h" |
| #include "platform/public/pipe.h" |
| #include "third_party/webrtc/files/stable/webrtc/api/data_channel_interface.h" |
| namespace location { |
| namespace nearby { |
| namespace connections { |
| namespace mediums { |
| |
| // Maximum data size: 1 MB |
| constexpr int kMaxDataSize = 1 * 1024 * 1024; |
| |
| // Defines the Socket implementation specific to WebRTC, which uses the WebRTC |
| // data channel to send and receive messages. |
| // |
| // Messages are buffered here to prevent the data channel from overflowing, |
| // which could lead to data loss. |
| class WebRtcSocket : public Socket { |
| public: |
| WebRtcSocket(const std::string& name, |
| rtc::scoped_refptr<webrtc::DataChannelInterface> data_channel); |
| ~WebRtcSocket() override = default; |
| |
| WebRtcSocket(const WebRtcSocket& other) = delete; |
| WebRtcSocket& operator=(const WebRtcSocket& other) = delete; |
| |
| // Overrides for location::nearby::Socket: |
| InputStream& GetInputStream() override; |
| OutputStream& GetOutputStream() override; |
| void Close() override; |
| |
| // Callback from WebRTC data channel when new message has been received from |
| // the remote. |
| void NotifyDataChannelMsgReceived(const ByteArray& message); |
| |
| // Callback from WebRTC data channel that the buffered data amount has |
| // changed. |
| void NotifyDataChannelBufferedAmountChanged(); |
| |
| // Listener class the gets called when the socket is closed. |
| struct SocketClosedListener { |
| std::function<void()> socket_closed_cb = DefaultCallback<>(); |
| }; |
| |
| void SetOnSocketClosedListener(SocketClosedListener&& listener); |
| |
| private: |
| class OutputStreamImpl : public OutputStream { |
| public: |
| explicit OutputStreamImpl(WebRtcSocket* const socket) : socket_(socket) {} |
| ~OutputStreamImpl() override = default; |
| |
| OutputStreamImpl(const OutputStreamImpl& other) = delete; |
| OutputStreamImpl& operator=(const OutputStreamImpl& other) = delete; |
| |
| // OutputStream: |
| Exception Write(const ByteArray& data) override; |
| Exception Flush() override; |
| Exception Close() override; |
| |
| private: |
| // |this| OutputStreamImpl is owned by |socket_|. |
| WebRtcSocket* const socket_; |
| }; |
| |
| void WakeUpWriter(); |
| bool IsClosed(); |
| bool SendMessage(const ByteArray& data); |
| void BlockUntilSufficientSpaceInBuffer(int length); |
| |
| std::string name_; |
| rtc::scoped_refptr<webrtc::DataChannelInterface> data_channel_; |
| |
| Pipe pipe_; |
| |
| OutputStreamImpl output_stream_{this}; |
| |
| AtomicBoolean closed_{false}; |
| |
| SocketClosedListener socket_closed_listener_; |
| |
| mutable Mutex backpressure_mutex_; |
| ConditionVariable buffer_variable_{&backpressure_mutex_}; |
| }; |
| |
| } // namespace mediums |
| } // namespace connections |
| } // namespace nearby |
| } // namespace location |
| |
| #endif // _CORE_INTERNAL_MEDIUMS_WEBRTC_WEBRTC_SOCKET_H_ |