Source/WebCore/Modules/mediastream/libwebrtc/LibWebRTCRtpSenderBackend.cpp

/*
 * Copyright (C) 2018 Apple Inc.
 *
 * 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
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 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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#include "config.h"
#include "LibWebRTCRtpSenderBackend.h"

#if ENABLE(WEB_RTC) && USE(LIBWEBRTC)

#include "JSDOMPromiseDeferred.h"
#include "LibWebRTCDTMFSenderBackend.h"
#include "LibWebRTCPeerConnectionBackend.h"
#include "LibWebRTCUtils.h"
#include "RTCPeerConnection.h"
#include "RTCRtpSender.h"
#include "ScriptExecutionContext.h"

namespace WebCore {

LibWebRTCRtpSenderBackend::LibWebRTCRtpSenderBackend(LibWebRTCPeerConnectionBackend& backend, rtc::scoped_refptr<webrtc::RtpSenderInterface>&& rtcSender, Source&& source)
    : m_peerConnectionBackend(makeWeakPtr(&backend))
    , m_rtcSender(WTFMove(rtcSender))
    , m_source(WTFMove(source))
{
    startSource();
}

LibWebRTCRtpSenderBackend::~LibWebRTCRtpSenderBackend()
{
    stopSource();
}

void LibWebRTCRtpSenderBackend::startSource()
{
    switchOn(m_source, [](Ref<RealtimeOutgoingAudioSource>& source) {
        source->start();
    }, [](Ref<RealtimeOutgoingVideoSource>& source) {
        source->start();
    }, [](std::nullptr_t&) {
    });
}

void LibWebRTCRtpSenderBackend::stopSource()
{
    switchOn(m_source, [](Ref<RealtimeOutgoingAudioSource>& source) {
        source->stop();
    }, [](Ref<RealtimeOutgoingVideoSource>& source) {
        source->stop();
    }, [](std::nullptr_t&) {
    });
    m_source = nullptr;
}

void LibWebRTCRtpSenderBackend::replaceTrack(ScriptExecutionContext& context, RTCRtpSender& sender, RefPtr<MediaStreamTrack>&& track, DOMPromiseDeferred<void>&& promise)
{
    if (!m_peerConnectionBackend) {
        promise.reject(Exception { InvalidStateError, "No WebRTC backend"_s });
        return;
    }

    if (!track)
        stopSource();
    else if (sender.track()) {
        switchOn(m_source, [&](Ref<RealtimeOutgoingAudioSource>& source) {
            ASSERT(track->source().type() == RealtimeMediaSource::Type::Audio);
            source->stop();
            source->setSource(track->privateTrack());
            source->start();
        }, [&](Ref<RealtimeOutgoingVideoSource>& source) {
            ASSERT(track->source().type() == RealtimeMediaSource::Type::Video);
            source->stop();
            source->setSource(track->privateTrack());
            source->start();
        }, [](std::nullptr_t&) {
            ASSERT_NOT_REACHED();
        });
    }

    // FIXME: Remove this postTask once this whole function is executed as part of the RTCPeerConnection operation queue.
    context.postTask([protectedSender = makeRef(sender), promise = WTFMove(promise), track = WTFMove(track), this](ScriptExecutionContext&) mutable {
        if (protectedSender->isStopped())
            return;

        if (!track) {
            protectedSender->setTrackToNull();
            promise.resolve();
            return;
        }

        bool hasTrack = protectedSender->track();
        protectedSender->setTrack(track.releaseNonNull());

        if (hasTrack) {
            promise.resolve();
            return;
        }

        m_peerConnectionBackend->setSenderSourceFromTrack(*this, *protectedSender->track());
        promise.resolve();
    });
}

RTCRtpSendParameters LibWebRTCRtpSenderBackend::getParameters() const
{
    if (!m_rtcSender)
        return { };

    m_currentParameters = m_rtcSender->GetParameters();
    return toRTCRtpSendParameters(*m_currentParameters);
}

void LibWebRTCRtpSenderBackend::setParameters(const RTCRtpSendParameters& parameters, DOMPromiseDeferred<void>&& promise)
{
    if (!m_rtcSender) {
        promise.reject(NotSupportedError);
        return;
    }

    if (!m_currentParameters) {
        promise.reject(Exception { InvalidStateError, "getParameters must be called before setParameters"_s });
        return;
    }

    auto rtcParameters = WTFMove(*m_currentParameters);
    updateRTCRtpSendParameters(parameters, rtcParameters);
    m_currentParameters = WTF::nullopt;

    auto error = m_rtcSender->SetParameters(rtcParameters);
    if (!error.ok()) {
        promise.reject(Exception { InvalidStateError, error.message() });
        return;
    }
    promise.resolve();
}

std::unique_ptr<RTCDTMFSenderBackend> LibWebRTCRtpSenderBackend::createDTMFBackend()
{
    return makeUnique<LibWebRTCDTMFSenderBackend>(m_rtcSender->GetDtmfSender());
}

RealtimeOutgoingVideoSource* LibWebRTCRtpSenderBackend::videoSource()
{
    return switchOn(m_source,
        [](Ref<RealtimeOutgoingVideoSource>& source) { return source.ptr(); },
        [](const auto&) -> RealtimeOutgoingVideoSource* { return nullptr; }
    );
}

bool LibWebRTCRtpSenderBackend::hasSource() const
{
    return switchOn(m_source,
        [](const std::nullptr_t&) { return false; },
        [](const auto&) { return true; }
    );
}

void LibWebRTCRtpSenderBackend::setSource(Source&& source)
{
    stopSource();
    m_source = WTFMove(source);
    startSource();
}

void LibWebRTCRtpSenderBackend::takeSource(LibWebRTCRtpSenderBackend& backend)
{
    ASSERT(backend.hasSource());
    stopSource();
    m_source = WTFMove(backend.m_source);
    backend.m_source = nullptr;
}

} // namespace WebCore

#endif // ENABLE(WEB_RTC) && USE(LIBWEBRTC)