api/rtpreceiverinterface.h

/*
 *  Copyright 2015 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.
 */

// This file contains interfaces for RtpReceivers
// http://w3c.github.io/webrtc-pc/#rtcrtpreceiver-interface

#ifndef WEBRTC_API_RTPRECEIVERINTERFACE_H_
#define WEBRTC_API_RTPRECEIVERINTERFACE_H_

#include <string>

#include "webrtc/api/mediatypes.h"
#include "webrtc/api/mediastreaminterface.h"
#include "webrtc/api/proxy.h"
#include "webrtc/api/rtpparameters.h"
#include "webrtc/base/refcount.h"
#include "webrtc/base/scoped_ref_ptr.h"

namespace webrtc {

class RtpReceiverObserverInterface {
 public:
  // Note: Currently if there are multiple RtpReceivers of the same media type,
  // they will all call OnFirstPacketReceived at once.
  //
  // In the future, it's likely that an RtpReceiver will only call
  // OnFirstPacketReceived when a packet is received specifically for its
  // SSRC/mid.
  virtual void OnFirstPacketReceived(cricket::MediaType media_type) = 0;

 protected:
  virtual ~RtpReceiverObserverInterface() {}
};

class RtpReceiverInterface : public rtc::RefCountInterface {
 public:
  virtual rtc::scoped_refptr<MediaStreamTrackInterface> track() const = 0;

  // Audio or video receiver?
  virtual cricket::MediaType media_type() const = 0;

  // Not to be confused with "mid", this is a field we can temporarily use
  // to uniquely identify a receiver until we implement Unified Plan SDP.
  virtual std::string id() const = 0;

  // The WebRTC specification only defines RTCRtpParameters in terms of senders,
  // but this API also applies them to receivers, similar to ORTC:
  // http://ortc.org/wp-content/uploads/2016/03/ortc.html#rtcrtpparameters*.
  virtual RtpParameters GetParameters() const = 0;
  // Currently, doesn't support changing any parameters, but may in the future.
  virtual bool SetParameters(const RtpParameters& parameters) = 0;

  // Does not take ownership of observer.
  // Must call SetObserver(nullptr) before the observer is destroyed.
  virtual void SetObserver(RtpReceiverObserverInterface* observer) = 0;

 protected:
  virtual ~RtpReceiverInterface() {}
};

// Define proxy for RtpReceiverInterface.
// TODO(deadbeef): Move this to .cc file and out of api/. What threads methods
// are called on is an implementation detail.
BEGIN_SIGNALING_PROXY_MAP(RtpReceiver)
  PROXY_SIGNALING_THREAD_DESTRUCTOR()
  PROXY_CONSTMETHOD0(rtc::scoped_refptr<MediaStreamTrackInterface>, track)
  PROXY_CONSTMETHOD0(cricket::MediaType, media_type)
  PROXY_CONSTMETHOD0(std::string, id)
  PROXY_CONSTMETHOD0(RtpParameters, GetParameters);
  PROXY_METHOD1(bool, SetParameters, const RtpParameters&)
  PROXY_METHOD1(void, SetObserver, RtpReceiverObserverInterface*);
END_PROXY_MAP()

}  // namespace webrtc

#endif  // WEBRTC_API_RTPRECEIVERINTERFACE_H_