Make cricket::VideoCapturer implement VideoSourceInterface

webrtc/media/base/videobroadcaster.h

+/*
+ *  Copyright (c) 2016 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_MEDIA_BASE_VIDEOBROADCASTER_H_
+#define WEBRTC_MEDIA_BASE_VIDEOBROADCASTER_H_
+
+#include <utility>
+#include <vector>
+
+#include "webrtc/base/thread_checker.h"
+#include "webrtc/media/base/videoframe.h"
+#include "webrtc/media/base/videosinkinterface.h"
+#include "webrtc/media/base/videosourceinterface.h"
+
+namespace rtc {
+
+class VideoBroadcaster : public VideoSourceInterface<cricket::VideoFrame>,
+                         public VideoSinkInterface<cricket::VideoFrame> {
+ public:
+  VideoBroadcaster();
+  void AddOrUpdateSink(VideoSinkInterface<cricket::VideoFrame>* sink,
+                       const VideoSinkWants& wants) override;
+  void RemoveSink(VideoSinkInterface<cricket::VideoFrame>* sink) override;
+
+  // Returns true if the next frame will be delivered to at least one sink.
+  bool frame_wanted() const;
+
+  // Returns VideoSinkWants a source is requested to fulfill. They are
+  // aggregated by all VideoSinkWants from all sinks.
+  VideoSinkWants wants() const;
+
+  void OnFrame(const cricket::VideoFrame& frame) override;
+
+ protected:
+  struct SinkPair {
+    SinkPair(VideoSinkInterface<cricket::VideoFrame>* sink,
+             VideoSinkWants wants)
+        : sink(sink), wants(wants) {}
+    VideoSinkInterface<cricket::VideoFrame>* sink;
+    VideoSinkWants wants;
+  };
+  SinkPair* FindSinkPair(const VideoSinkInterface<cricket::VideoFrame>* sink);
+
+  ThreadChecker thread_checker_;
+
+  VideoSinkWants current_wants_;
+
+  std::vector<SinkPair> sinks_;
+};
+
+}  // namespace rtc
+
+#endif  // WEBRTC_MEDIA_BASE_VIDEOBROADCASTER_H_