Add DesktopCapturerId and attach it to DesktopFrame

webrtc/modules/desktop_capture/desktop_frame.h

 /*
  *  Copyright (c) 2013 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_MODULES_DESKTOP_CAPTURE_DESKTOP_FRAME_H_
 #define WEBRTC_MODULES_DESKTOP_CAPTURE_DESKTOP_FRAME_H_
 
 #include <memory>
 
 #include "webrtc/base/constructormagic.h"
+#include "webrtc/modules/desktop_capture/desktop_capture_types.h"
 #include "webrtc/modules/desktop_capture/desktop_geometry.h"
 #include "webrtc/modules/desktop_capture/desktop_region.h"
 #include "webrtc/modules/desktop_capture/shared_memory.h"
 #include "webrtc/typedefs.h"
 
 namespace webrtc {
 
 // DesktopFrame represents a video frame captured from the screen.
 class DesktopFrame {
  public:
@@ skipping 34 matching lines @@
   void CopyPixelsFrom(const uint8_t* src_buffer,
                       int src_stride,
                       const DesktopRect& dest_rect);
   void CopyPixelsFrom(const DesktopFrame& src_frame,
                       const DesktopVector& src_pos,
                       const DesktopRect& dest_rect);
 
   // A helper to return the data pointer of a frame at the specified position.
   uint8_t* GetFrameDataAtPos(const DesktopVector& pos) const;
 
+  // The generator of current DesktopFrame. Not all DesktopCapturer
+  // implementations set this field.
+  DesktopCapturerId capturer_id() const { return capturer_id_; }

[Sergey Ulanov, 2017/03/21 00:39:36]

I think this should be uint32_t if we want it to be extensible for capturers
outside of WebRTC

[Hzj_jie, 2017/03/21 18:40:40]

Done.

+  void set_capturer_id(DesktopCapturerId capturer_id) {
+    capturer_id_ = capturer_id;
+  }
+
  protected:
   DesktopFrame(DesktopSize size,
                int stride,
                uint8_t* data,
                SharedMemory* shared_memory);
 
   // Ownership of the buffers is defined by the classes that inherit from this
   // class. They must guarantee that the buffer is not deleted before the frame
   // is deleted.
   uint8_t* const data_;
   SharedMemory* const shared_memory_;
 
  private:
   const DesktopSize size_;
   const int stride_;
 
   DesktopRegion updated_region_;
   DesktopVector dpi_;
   int64_t capture_time_ms_;
+  DesktopCapturerId capturer_id_;
 
   RTC_DISALLOW_COPY_AND_ASSIGN(DesktopFrame);
 };
 
 // A DesktopFrame that stores data in the heap.
 class BasicDesktopFrame : public DesktopFrame {
  public:
   explicit BasicDesktopFrame(DesktopSize size);
   ~BasicDesktopFrame() override;
 
@@ skipping 24 matching lines @@
   ~SharedMemoryDesktopFrame() override;
 
  private:
   RTC_DISALLOW_COPY_AND_ASSIGN(SharedMemoryDesktopFrame);
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_DESKTOP_CAPTURE_DESKTOP_FRAME_H_