third_party/WebKit/Source/modules/mediastream/MediaStreamTrack.cpp

/*
 * Copyright (C) 2011 Google Inc. All rights reserved.
 * Copyright (C) 2011 Ericsson AB. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 * 2.  Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "modules/mediastream/MediaStreamTrack.h"

#include "bindings/core/v8/ExceptionMessages.h"
#include "core/dom/Document.h"
#include "core/dom/ExceptionCode.h"
#include "core/dom/ExecutionContext.h"
#include "core/events/Event.h"
#include "core/frame/Deprecation.h"
#include "modules/mediastream/MediaConstraintsImpl.h"
#include "modules/mediastream/MediaStream.h"
#include "modules/mediastream/MediaStreamTrackSourcesCallback.h"
#include "modules/mediastream/MediaStreamTrackSourcesRequestImpl.h"
#include "modules/mediastream/MediaTrackSettings.h"
#include "modules/mediastream/UserMediaController.h"
#include "platform/mediastream/MediaStreamCenter.h"
#include "platform/mediastream/MediaStreamComponent.h"
#include "public/platform/WebMediaStreamTrack.h"
#include "public/platform/WebSourceInfo.h"
#include "wtf/Assertions.h"
#include <memory>

namespace blink {

MediaStreamTrack* MediaStreamTrack::create(ExecutionContext* context,
                                           MediaStreamComponent* component) {
  MediaStreamTrack* track = new MediaStreamTrack(context, component);
  track->suspendIfNeeded();
  return track;
}

MediaStreamTrack::MediaStreamTrack(ExecutionContext* context,
                                   MediaStreamComponent* component)
    : ActiveScriptWrappable(this),
      ActiveDOMObject(context),
      m_readyState(MediaStreamSource::ReadyStateLive),
      m_isIteratingRegisteredMediaStreams(false),
      m_stopped(false),
      m_component(component),
      // The source's constraints aren't yet initialized at creation time.
      m_constraints() {
  m_component->source()->addObserver(this);
}

MediaStreamTrack::~MediaStreamTrack() {}

String MediaStreamTrack::kind() const {
  DEFINE_STATIC_LOCAL(String, audioKind, ("audio"));
  DEFINE_STATIC_LOCAL(String, videoKind, ("video"));

  switch (m_component->source()->type()) {
    case MediaStreamSource::TypeAudio:
      return audioKind;
    case MediaStreamSource::TypeVideo:
      return videoKind;
  }

  NOTREACHED();
  return audioKind;
}

String MediaStreamTrack::id() const {
  return m_component->id();
}

String MediaStreamTrack::label() const {
  return m_component->source()->name();
}

bool MediaStreamTrack::enabled() const {
  return m_component->enabled();
}

void MediaStreamTrack::setEnabled(bool enabled) {
  if (enabled == m_component->enabled())
    return;

  m_component->setEnabled(enabled);

  if (!ended())
    MediaStreamCenter::instance().didSetMediaStreamTrackEnabled(
        m_component.get());
}

bool MediaStreamTrack::muted() const {
  return m_component->muted();
}

bool MediaStreamTrack::remote() const {
  return m_component->source()->remote();
}

String MediaStreamTrack::readyState() const {
  if (ended())
    return "ended";

  switch (m_readyState) {
    case MediaStreamSource::ReadyStateLive:
      return "live";
    case MediaStreamSource::ReadyStateMuted:
      return "muted";
    case MediaStreamSource::ReadyStateEnded:
      return "ended";
  }

  NOTREACHED();
  return String();
}

void MediaStreamTrack::getSources(ExecutionContext* context,
                                  MediaStreamTrackSourcesCallback* callback,
                                  ExceptionState& exceptionState) {
  LocalFrame* frame = toDocument(context)->frame();
  UserMediaController* userMedia = UserMediaController::from(frame);
  if (!userMedia) {
    exceptionState.throwDOMException(
        NotSupportedError,
        "No sources controller available; is this a detached window?");
    return;
  }
  Deprecation::countDeprecation(context,
                                UseCounter::MediaStreamTrackGetSources);
  MediaStreamTrackSourcesRequest* request =
      MediaStreamTrackSourcesRequestImpl::create(*context, callback);
  userMedia->requestSources(request);
}

void MediaStreamTrack::stopTrack(ExceptionState& exceptionState) {
  if (ended())
    return;

  m_readyState = MediaStreamSource::ReadyStateEnded;
  MediaStreamCenter::instance().didStopMediaStreamTrack(component());
  dispatchEvent(Event::create(EventTypeNames::ended));
  propagateTrackEnded();
}

MediaStreamTrack* MediaStreamTrack::clone(ExecutionContext* context) {
  MediaStreamComponent* clonedComponent =
      MediaStreamComponent::create(component()->source());
  MediaStreamTrack* clonedTrack =
      MediaStreamTrack::create(context, clonedComponent);
  MediaStreamCenter::instance().didCreateMediaStreamTrack(clonedComponent);
  return clonedTrack;
}

void MediaStreamTrack::getConstraints(MediaTrackConstraints& constraints) {
  MediaConstraintsImpl::convertConstraints(m_constraints, constraints);
}

void MediaStreamTrack::setConstraints(const WebMediaConstraints& constraints) {
  m_constraints = constraints;
}

void MediaStreamTrack::getSettings(MediaTrackSettings& settings) {
  WebMediaStreamTrack::Settings platformSettings;
  m_component->getSettings(platformSettings);
  if (platformSettings.hasFrameRate()) {
    settings.setFrameRate(platformSettings.frameRate);
  }
  if (platformSettings.hasWidth()) {
    settings.setWidth(platformSettings.width);
  }
  if (platformSettings.hasHeight()) {
    settings.setHeight(platformSettings.height);
  }
  settings.setDeviceId(platformSettings.deviceId);
}

bool MediaStreamTrack::ended() const {
  return m_stopped || (m_readyState == MediaStreamSource::ReadyStateEnded);
}

void MediaStreamTrack::sourceChangedState() {
  if (ended())
    return;

  m_readyState = m_component->source()->getReadyState();
  switch (m_readyState) {
    case MediaStreamSource::ReadyStateLive:
      m_component->setMuted(false);
      dispatchEvent(Event::create(EventTypeNames::unmute));
      break;
    case MediaStreamSource::ReadyStateMuted:
      m_component->setMuted(true);
      dispatchEvent(Event::create(EventTypeNames::mute));
      break;
    case MediaStreamSource::ReadyStateEnded:
      dispatchEvent(Event::create(EventTypeNames::ended));
      propagateTrackEnded();
      break;
  }
}

void MediaStreamTrack::propagateTrackEnded() {
  CHECK(!m_isIteratingRegisteredMediaStreams);
  m_isIteratingRegisteredMediaStreams = true;
  for (HeapHashSet<Member<MediaStream>>::iterator iter =
           m_registeredMediaStreams.begin();
       iter != m_registeredMediaStreams.end(); ++iter)
    (*iter)->trackEnded();
  m_isIteratingRegisteredMediaStreams = false;
}

void MediaStreamTrack::contextDestroyed() {
  m_stopped = true;
}

bool MediaStreamTrack::hasPendingActivity() const {
  // If 'ended' listeners exist and the object hasn't yet reached
  // that state, keep the object alive.
  //
  // An otherwise unreachable MediaStreamTrack object in an non-ended
  // state will otherwise indirectly be transitioned to the 'ended' state
  // while finalizing m_component. Which dispatches an 'ended' event,
  // referring to this object as the target. If this object is then GCed
  // at the same time, v8 objects will retain (wrapper) references to
  // this dead MediaStreamTrack object. Bad.
  //
  // Hence insisting on keeping this object alive until the 'ended'
  // state has been reached & handled.
  return !ended() && hasEventListeners(EventTypeNames::ended);
}

std::unique_ptr<AudioSourceProvider> MediaStreamTrack::createWebAudioSource() {
  return MediaStreamCenter::instance().createWebAudioSourceFromMediaStreamTrack(
      component());
}

void MediaStreamTrack::registerMediaStream(MediaStream* mediaStream) {
  CHECK(!m_isIteratingRegisteredMediaStreams);
  CHECK(!m_registeredMediaStreams.contains(mediaStream));
  m_registeredMediaStreams.add(mediaStream);
}

void MediaStreamTrack::unregisterMediaStream(MediaStream* mediaStream) {
  CHECK(!m_isIteratingRegisteredMediaStreams);
  HeapHashSet<Member<MediaStream>>::iterator iter =
      m_registeredMediaStreams.find(mediaStream);
  CHECK(iter != m_registeredMediaStreams.end());
  m_registeredMediaStreams.remove(iter);
}

const AtomicString& MediaStreamTrack::interfaceName() const {
  return EventTargetNames::MediaStreamTrack;
}

ExecutionContext* MediaStreamTrack::getExecutionContext() const {
  return ActiveDOMObject::getExecutionContext();
}

DEFINE_TRACE(MediaStreamTrack) {
  visitor->trace(m_registeredMediaStreams);
  visitor->trace(m_component);
  EventTargetWithInlineData::trace(visitor);
  ActiveDOMObject::trace(visitor);
}

}  // namespace blink