Source/WebCore/Modules/mediastream/MediaDevicesRequest.cpp

/*
 * Copyright (C) 2015-2016 Apple Inc. 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. ``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
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
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#include "config.h"
#include "MediaDevicesRequest.h"

#if ENABLE(MEDIA_STREAM)

#include "CaptureDevice.h"
#include "Document.h"
#include "Frame.h"
#include "JSMediaDeviceInfo.h"
#include "MediaDevicesEnumerationRequest.h"
#include "RealtimeMediaSourceCenter.h"
#include "SecurityOrigin.h"
#include "UserMediaController.h"
#include <wtf/MainThread.h>
#include <wtf/SHA1.h>

namespace WebCore {

inline MediaDevicesRequest::MediaDevicesRequest(Document& document, MediaDevices::EnumerateDevicesPromise&& promise)
    : ContextDestructionObserver(&document)
    , m_promise(WTFMove(promise))
{
}

Ref<MediaDevicesRequest> MediaDevicesRequest::create(Document& document, MediaDevices::EnumerateDevicesPromise&& promise)
{
    return adoptRef(*new MediaDevicesRequest(document, WTFMove(promise)));
}

MediaDevicesRequest::~MediaDevicesRequest()
{
    // This should only get destroyed after the enumeration request has completed or has been canceled.
    ASSERT(!m_enumerationRequest || m_enumerationRequest->wasCanceled());
}

SecurityOrigin* MediaDevicesRequest::securityOrigin() const
{
    if (scriptExecutionContext())
        return scriptExecutionContext()->securityOrigin();

    return nullptr;
}

void MediaDevicesRequest::contextDestroyed()
{
    // The call to m_enumerationRequest->cancel() might delete this.
    auto protectedThis = makeRef(*this);

    if (m_enumerationRequest) {
        m_enumerationRequest->cancel();
        m_enumerationRequest = nullptr;
    }
    ContextDestructionObserver::contextDestroyed();
}

void MediaDevicesRequest::filterDeviceList(Vector<Ref<MediaDeviceInfo>>& devices)
{
#if !PLATFORM(COCOA)
    UNUSED_PARAM(devices);
#else

#if PLATFORM(IOS)
    static const int defaultCameraCount = 2;
#endif
#if PLATFORM(MAC)
    static const int defaultCameraCount = 1;
#endif
    static const int defaultMicrophoneCount = 1;

    int cameraCount = 0;
    int microphoneCount = 0;
    devices.removeAllMatching([&](const Ref<MediaDeviceInfo>& device) -> bool {
        if (device->kind() == MediaDeviceInfo::Kind::Videoinput && ++cameraCount > defaultCameraCount)
            return true;
        if (device->kind() == MediaDeviceInfo::Kind::Audioinput && ++microphoneCount > defaultMicrophoneCount)
            return true;

        return false;
    });

#endif
}

void MediaDevicesRequest::start()
{
    // This lambda keeps |this| alive until the request completes or is canceled.
    auto completion = [this, protectedThis = makeRef(*this)] (const Vector<CaptureDevice>& captureDevices, const String& deviceIdentifierHashSalt, bool originHasPersistentAccess) mutable {

        m_enumerationRequest = nullptr;

        if (!scriptExecutionContext())
            return;

        Document& document = downcast<Document>(*scriptExecutionContext());
        document.setDeviceIDHashSalt(deviceIdentifierHashSalt);

        Vector<Ref<MediaDeviceInfo>> devices;
        for (auto& deviceInfo : captureDevices) {
            auto label = emptyString();
            if (originHasPersistentAccess || document.hasHadActiveMediaStreamTrack())
                label = deviceInfo.label();

            auto id = RealtimeMediaSourceCenter::singleton().hashStringWithSalt(deviceInfo.persistentId(), deviceIdentifierHashSalt);
            if (id.isEmpty())
                continue;

            auto groupId = RealtimeMediaSourceCenter::singleton().hashStringWithSalt(deviceInfo.groupId(), deviceIdentifierHashSalt);
            auto deviceType = deviceInfo.type() == CaptureDevice::DeviceType::Microphone ? MediaDeviceInfo::Kind::Audioinput : MediaDeviceInfo::Kind::Videoinput;
            devices.append(MediaDeviceInfo::create(scriptExecutionContext(), label, id, groupId, deviceType));
        }

        if (!originHasPersistentAccess && !document.hasHadActiveMediaStreamTrack())
            filterDeviceList(devices);

        callOnMainThread([protectedThis = makeRef(*this), devices = WTFMove(devices)]() mutable {
            protectedThis->m_promise.resolve(devices);
        });
    };

    m_enumerationRequest = MediaDevicesEnumerationRequest::create(*downcast<Document>(scriptExecutionContext()), WTFMove(completion));
    m_enumerationRequest->start();
}

} // namespace WebCore

#endif // ENABLE(MEDIA_STREAM)