Reland Use CopyOnWriteBuffer instead of Buffer to avoid unnecessary copies.

webrtc/pc/channel.h

 /*
  *  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.
  */
 
@@ skipping 173 matching lines @@
     return transport_controller_->signaling_thread();
   }
   bool rtcp_transport_enabled() const { return rtcp_transport_enabled_; }
 
   void ConnectToTransportChannel(TransportChannel* tc);
   void DisconnectFromTransportChannel(TransportChannel* tc);
 
   void FlushRtcpMessages();
 
   // NetworkInterface implementation, called by MediaEngine
-  bool SendPacket(rtc::Buffer* packet,
-                          const rtc::PacketOptions& options) override;
-  bool SendRtcp(rtc::Buffer* packet, const rtc::PacketOptions& options)
-      override;
+  bool SendPacket(rtc::CopyOnWriteBuffer* packet,
+                  const rtc::PacketOptions& options) override;
+  bool SendRtcp(rtc::CopyOnWriteBuffer* packet,
+                const rtc::PacketOptions& options) override;
 
   // From TransportChannel
   void OnWritableState(TransportChannel* channel);
   virtual void OnChannelRead(TransportChannel* channel,
                              const char* data,
                              size_t len,
                              const rtc::PacketTime& packet_time,
                              int flags);
   void OnReadyToSend(TransportChannel* channel);
 
   void OnDtlsState(TransportChannel* channel, DtlsTransportState state);
 
   bool PacketIsRtcp(const TransportChannel* channel, const char* data,
                     size_t len);
   bool SendPacket(bool rtcp,
-                  rtc::Buffer* packet,
+                  rtc::CopyOnWriteBuffer* packet,
                   const rtc::PacketOptions& options);
-  virtual bool WantsPacket(bool rtcp, rtc::Buffer* packet);
-  void HandlePacket(bool rtcp, rtc::Buffer* packet,
+  virtual bool WantsPacket(bool rtcp, const rtc::CopyOnWriteBuffer* packet);
+  void HandlePacket(bool rtcp, rtc::CopyOnWriteBuffer* packet,
                     const rtc::PacketTime& packet_time);
 
   void EnableMedia_w();
   void DisableMedia_w();
   void UpdateWritableState_w();
   void ChannelWritable_w();
   void ChannelNotWritable_w();
   bool AddRecvStream_w(const StreamParams& sp);
   bool RemoveRecvStream_w(uint32_t ssrc);
   bool AddSendStream_w(const StreamParams& sp);
@@ skipping 268 matching lines @@
  public:
   DataChannel(rtc::Thread* thread,
               DataMediaChannel* media_channel,
               TransportController* transport_controller,
               const std::string& content_name,
               bool rtcp);
   ~DataChannel();
   bool Init();
 
   virtual bool SendData(const SendDataParams& params,
-                        const rtc::Buffer& payload,
+                        const rtc::CopyOnWriteBuffer& payload,
                         SendDataResult* result);
 
   void StartMediaMonitor(int cms);
   void StopMediaMonitor();
 
   // Should be called on the signaling thread only.
   bool ready_to_send_data() const {
     return ready_to_send_data_;
   }
 
   sigslot::signal2<DataChannel*, const DataMediaInfo&> SignalMediaMonitor;
   sigslot::signal2<DataChannel*, const std::vector<ConnectionInfo>&>
       SignalConnectionMonitor;
-  sigslot::signal3<DataChannel*, const ReceiveDataParams&, const rtc::Buffer&>
-      SignalDataReceived;
+  sigslot::signal3<DataChannel*, const ReceiveDataParams&,
+      const rtc::CopyOnWriteBuffer&> SignalDataReceived;
   // Signal for notifying when the channel becomes ready to send data.
   // That occurs when the channel is enabled, the transport is writable,
   // both local and remote descriptions are set, and the channel is unblocked.
   sigslot::signal1<bool> SignalReadyToSendData;
   // Signal for notifying that the remote side has closed the DataChannel.
   sigslot::signal1<uint32_t> SignalStreamClosedRemotely;
 
  protected:
   // downcasts a MediaChannel.
   virtual DataMediaChannel* media_channel() const {
     return static_cast<DataMediaChannel*>(BaseChannel::media_channel());
   }
 
  private:
   struct SendDataMessageData : public rtc::MessageData {
     SendDataMessageData(const SendDataParams& params,
-                        const rtc::Buffer* payload,
+                        const rtc::CopyOnWriteBuffer* payload,
                         SendDataResult* result)
         : params(params),
           payload(payload),
           result(result),
           succeeded(false) {
     }
 
     const SendDataParams& params;
-    const rtc::Buffer* payload;
+    const rtc::CopyOnWriteBuffer* payload;
     SendDataResult* result;
     bool succeeded;
   };
 
   struct DataReceivedMessageData : public rtc::MessageData {
     // We copy the data because the data will become invalid after we
     // handle DataMediaChannel::SignalDataReceived but before we fire
     // SignalDataReceived.
     DataReceivedMessageData(
         const ReceiveDataParams& params, const char* data, size_t len)
         : params(params),
           payload(data, len) {
     }
     const ReceiveDataParams params;
-    const rtc::Buffer payload;
+    const rtc::CopyOnWriteBuffer payload;
   };
 
   typedef rtc::TypedMessageData<bool> DataChannelReadyToSendMessageData;
 
   // overrides from BaseChannel
   virtual const ContentInfo* GetFirstContent(const SessionDescription* sdesc);
   // If data_channel_type_ is DCT_NONE, set it.  Otherwise, check that
   // it's the same as what was set previously.  Returns false if it's
   // set to one type one type and changed to another type later.
   bool SetDataChannelType(DataChannelType new_data_channel_type,
                           std::string* error_desc);
   // Same as SetDataChannelType, but extracts the type from the
   // DataContentDescription.
   bool SetDataChannelTypeFromContent(const DataContentDescription* content,
                                      std::string* error_desc);
   virtual bool SetLocalContent_w(const MediaContentDescription* content,
                                  ContentAction action,
                                  std::string* error_desc);
   virtual bool SetRemoteContent_w(const MediaContentDescription* content,
                                   ContentAction action,
                                   std::string* error_desc);
   virtual void ChangeState();
-  virtual bool WantsPacket(bool rtcp, rtc::Buffer* packet);
+  virtual bool WantsPacket(bool rtcp, const rtc::CopyOnWriteBuffer* packet);
 
   virtual void OnMessage(rtc::Message* pmsg);
   virtual void GetSrtpCryptoSuites(std::vector<int>* crypto_suites) const;
   virtual void OnConnectionMonitorUpdate(
       ConnectionMonitor* monitor, const std::vector<ConnectionInfo>& infos);
   virtual void OnMediaMonitorUpdate(
       DataMediaChannel* media_channel, const DataMediaInfo& info);
   virtual bool ShouldSetupDtlsSrtp() const;
   void OnDataReceived(
       const ReceiveDataParams& params, const char* data, size_t len);
@@ skipping 11 matching lines @@
   // SetSendParameters.
   DataSendParameters last_send_params_;
   // Last DataRecvParameters sent down to the media_channel() via
   // SetRecvParameters.
   DataRecvParameters last_recv_params_;
 };
 
 }  // namespace cricket
 
 #endif  // WEBRTC_PC_CHANNEL_H_