qaudiodevice.cpp

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// Copyright (C) 2016 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
 
#include "qaudiosystem_p.h"
#include "qaudiodevice_p.h"
#include <private/qplatformaudiodevices_p.h>
#include <private/qplatformmediaintegration_p.h>
 
#include <QtCore/qmap.h>
 
QT_BEGIN_NAMESPACE
 
/*!
    \class QAudioDevice
    \brief The QAudioDevice class provides an information about audio devices and their
           functionality.
    \inmodule QtMultimedia
    \ingroup multimedia
    \ingroup multimedia_audio
 
    QAudioDevice describes an audio device available in the system, either for input or for
    playback.
 
    A QAudioDevice is used by Qt to construct
    classes that communicate with the device -- such as
    QAudioSource, and QAudioSink. It is also used to determine the
    input or output device to use in a capture session or during media playback.
 
    The QAudioDevice instance retains its properties throughout its lifetime,
    even if the corresponding physical device is disconnected or its settings are
    modified. To keep track of updated properties, the user should load new instances
    of QAudioDevice from \l{QMediaDevices} when the relevant signals are fired.
 
    You can also query each device for the formats it supports. A
    format in this context is a set consisting of a channel count, sample rate, and sample type. A
    format is represented by the QAudioFormat class.
 
    The values supported by the device for each of these parameters can be
    fetched with minimumChannelCount(), maximumChannelCount(),
    minimumSampleRate(), maximumSampleRate() and supportedSampleFormats(). The
    combinations supported are dependent on the audio device capabilities. If
    you need a specific format, you can check if the device supports it with
    isFormatSupported(). For instance:
 
    \snippet multimedia-snippets/audio.cpp Audio output setup
 
    The set of available devices can be retrieved from the QMediaDevices class.
 
    For instance:
 
    \snippet multimedia-snippets/audio.cpp Dumping audio formats
 
    In this code sample, we loop through all devices that are able to output
    sound, i.e., play an audio stream in a supported format. For each device we
    find, we simply print the deviceName().
 
    \sa QAudioSink, QAudioSource, QAudioFormat
*/
 
/*!
    \qmlvaluetype audioDevice
    \inqmlmodule QtMultimedia
    \since 6.2
    //! \nativetype QAudioDevice
    \brief Describes an audio device.
    \ingroup multimedia_qml
    \ingroup multimedia_audio_qml
    \ingroup qmlvaluetypes
 
    The audioDevice value type describes the properties of an audio device that
    is connected to the system.
 
    The audioDevice instance retains its properties throughout its lifetime,
    even if the corresponding physical device is disconnected or its settings are
    modified. To keep track of updated properties, the user should load new instances
    of audioDevice from \l{MediaDevices} when the relevant signals are fired.
 
    The list of audio input or output devices can be queried from the \l{MediaDevices}
    type. To select a certain audio device for input or output set it as the device
    on \l{AudioInput} or \l{AudioOutput}.
 
    \qml
    MediaPlayer {
        audioOutput: AudioOutput {
            device: mediaDevices.defaultAudioOutput
        }
    }
    MediaDevices {
        id: mediaDevices
    }
    \endqml
*/
 
/*!
    Constructs a null QAudioDevice object.
*/
QAudioDevice::QAudioDevice() = default;
 
/*!
    Constructs a copy of \a other.
*/
QAudioDevice::QAudioDevice(const QAudioDevice &other) = default;
 
/*!
    \fn QAudioDevice::QAudioDevice(QAudioDevice &&other)
 
    Move constructs from \a other.
*/
/*!
    \fn void QAudioDevice::swap(QAudioDevice &other) noexcept
 
    Swaps the audio device with the \a other.
*/
/*!
    Destroy this audio device info.
*/
QAudioDevice::~QAudioDevice() = default;
 
/*!
    Sets the QAudioDevice object to be equal to \a other.
*/
QAudioDevice &QAudioDevice::operator=(const QAudioDevice &other) = default;
 
/*!
    \fn QAudioDevice& QAudioDevice::operator=(QAudioDevice &&other)
 
    Moves \a other into this QAudioDevice object.
*/
 
/*!
    Returns true if this QAudioDevice class represents the
    same audio device as \a other.
*/
bool QAudioDevice::operator==(const QAudioDevice &other) const
{
    return mode() == other.mode() && id() == other.id();
}
 
/*!
    Returns true if this QAudioDevice class represents a
    different audio device than \a other
*/
bool QAudioDevice::operator!=(const QAudioDevice &other) const
{
    return !operator==(other);
}
 
/*!
    Returns whether this QAudioDevice object holds a valid device definition.
*/
bool QAudioDevice::isNull() const
{
    return d == nullptr;
}
 
/*!
    \qmlproperty string QtMultimedia::audioDevice::id
 
    Holds an identifier for the audio device.
 
    Device names vary depending on the platform/audio plugin being used.
 
    They are a unique identifier for the audio device.
*/
 
/*!
    \property QAudioDevice::id
 
    Returns an identifier for the audio device.
 
    Device names vary depending on the platform/audio plugin being used.
 
    They are a unique identifier for the audio device.
*/
QByteArray QAudioDevice::id() const
{
    return isNull() ? QByteArray() : d->id;
}
 
/*!
    \qmlproperty string QtMultimedia::audioDevice::description
 
    Holds a human readable name of the audio device.
 
    Use this string to present the device to the user.
*/
 
/*!
    \property QAudioDevice::description
 
    Returns a human readable name of the audio device.
 
    Use this string to present the device to the user.
*/
QString QAudioDevice::description() const
{
    return isNull() ? QString() : d->description;
}
 
/*!
    \qmlproperty bool QtMultimedia::audioDevice::isDefault
 
    Is true if this is the default audio device.
*/
 
/*!
    \property QAudioDevice::isDefault
 
    Returns true if this is the default audio device.
*/
bool QAudioDevice::isDefault() const
{
    return d ? d->isDefault : false;
}
 
/*!
    Returns true if the supplied \a settings are supported by the audio
    device described by this QAudioDevice.
*/
bool QAudioDevice::isFormatSupported(const QAudioFormat &settings) const
{
    if (isNull())
        return false;
    auto result = d->isFormatSupported(settings);
    return result ? *result : false;
}
 
/*!
    Returns the default audio format settings for this device.
 
    These settings are provided by the platform/audio plugin being used.
 
    They are also dependent on the \l {QtAudio}::Mode being used.
 
    A typical audio system would provide something like:
    \list
    \li Input settings: 48000Hz mono 16 bit.
    \li Output settings: 48000Hz stereo 16 bit.
    \endlist
*/
QAudioFormat QAudioDevice::preferredFormat() const
{
    if (isNull())
        return QAudioFormat();
    auto fmt = d->preferredFormat();
    return fmt ? *fmt : QAudioFormat();
}
 
/*!
    Returns the minimum supported sample rate (in Hertz).
*/
int QAudioDevice::minimumSampleRate() const
{
    if (isNull())
        return 0;
    auto rate = d->minimumSampleRate();
    return rate ? *rate : 0;
}
 
/*!
    Returns the maximum supported sample rate (in Hertz).
*/
int QAudioDevice::maximumSampleRate() const
{
    if (isNull())
        return 0;
    auto rate = d->maximumSampleRate();
    return rate ? *rate : 0;
}
 
/*!
    Returns the minimum number of supported channel counts.
 
    This is typically 1 for mono sound, or 2 for stereo sound.
*/
int QAudioDevice::minimumChannelCount() const
{
    if (isNull())
        return 0;
    auto count = d->minimumChannelCount();
    return count ? *count : 0;
}
 
/*!
    Returns the maximum number of supported channel counts.
 
    This is typically 1 for mono sound, or 2 for stereo sound.
*/
int QAudioDevice::maximumChannelCount() const
{
    if (isNull())
        return 0;
    auto count = d->maximumChannelCount();
    return count ? *count : 0;
}
 
/*!
    Returns a list of supported sample types.
*/
QList<QAudioFormat::SampleFormat> QAudioDevice::supportedSampleFormats() const
{
    if (isNull())
        return QList<QAudioFormat::SampleFormat>();
    auto formats = d->supportedSampleFormats();
    return formats ? *formats : QList<QAudioFormat::SampleFormat>();
}
 
/*!
    Returns the channel configuration of the device.
*/
QAudioFormat::ChannelConfig QAudioDevice::channelConfiguration() const
{
    if (isNull())
        return QAudioFormat::ChannelConfigUnknown;
    auto config = d->channelConfiguration();
    return config ? *config : QAudioFormat::ChannelConfigUnknown;
}
 
/*!
    \fn QAudioDevicePrivate QAudioDevice::handle() const
    \internal
*/
/*!
    \internal
*/
QAudioDevice::QAudioDevice(QAudioDevicePrivate *p) : d(p) { }
 
/*!
    \enum QAudioDevice::Mode
 
    Describes the mode of this device.
 
    \value Null
         A null device.
    \value Input
         An input device.
    \value Output
        An output device.
*/
 
/*!
    \qmlproperty enumeration QtMultimedia::audioDevice::mode
    \qmlenumeratorsfrom [AudioDevice] QAudioDevice::Mode
 
    Holds whether this device is an input or output device.
 
    The returned value can be one of the following:
*/
 
/*!
    \property QAudioDevice::mode
 
    Returns whether this device is an input or output device.
*/
QAudioDevice::Mode QAudioDevice::mode() const
{
    return d ? d->mode : Null;
}
 
#ifndef QT_NO_DEBUG_STREAM
QDebug operator<<(QDebug dbg, QAudioDevice::Mode mode)
{
    QDebugStateSaver saver(dbg);
    dbg.nospace();
    switch (mode) {
    case QAudioDevice::Input:
        dbg << "QAudioDevice::Input";
        break;
    case QAudioDevice::Output:
        dbg << "QAudioDevice::Output";
        break;
    case QAudioDevice::Null:
        dbg << "QAudioDevice::Null";
        break;
    }
    return dbg;
}
#endif
 
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 
QT_DEFINE_QESDP_SPECIALIZATION_DTOR(QAudioDevicePrivate)
 
QAudioDevicePrivate::QAudioDevicePrivate(QByteArray i, QAudioDevice::Mode m, QString description,
                                         bool isDefault, std::future<AudioDeviceFormat> format)
    : id(std::move(i)),
      mode(m),
      description(std::move(description)),
      isDefault(isDefault),
      m_deviceFormat(std::move(format).share())
{
}
 
namespace {
 
std::future<QAudioDevicePrivate::AudioDeviceFormat>
makeFuture(QAudioDevicePrivate::AudioDeviceFormat format)
{
    std::promise<QAudioDevicePrivate::AudioDeviceFormat> promise;
    promise.set_value(std::move(format));
    return promise.get_future();
}
 
} // namespace
 
QAudioDevicePrivate::QAudioDevicePrivate(const QByteArray &i, QAudioDevice::Mode m,
                                         QString description, bool isDefault,
                                         AudioDeviceFormat format)
    : QAudioDevicePrivate(i, m, std::move(description), isDefault, makeFuture(std::move(format)))
{
}
 
QAudioDevicePrivate::~QAudioDevicePrivate() = default;
 
template <typename F>
QAudioDeviceExpected<std::invoke_result_t<F, const QAudioDevicePrivate::AudioDeviceFormat &>>
QAudioDevicePrivate::doWithDeviceFormat(F &&f) const
{
    if (m_deviceFormat.valid()) {
        auto status = m_deviceFormat.wait_for(formatProbeTimeout);
        switch (status) {
        case std::future_status::ready:
        case std::future_status::deferred:
            return f(m_deviceFormat.get());
        case std::future_status::timeout:
            return q23::unexpected{ QAudioDeviceFormatError::Timeout };
        default:
            Q_UNREACHABLE_RETURN(q23::unexpected{ QAudioDeviceFormatError::InvalidFuture });
        }
    }
    return q23::unexpected{ QAudioDeviceFormatError::InvalidFuture };
}
 
QAudioDeviceExpected<QAudioDevicePrivate::AudioDeviceFormat> QAudioDevicePrivate::format() const
{
    return doWithDeviceFormat([](const AudioDeviceFormat &fmt) {
        return AudioDeviceFormat{ fmt };
    });
}
 
QAudioDeviceExpected<QAudioFormat> QAudioDevicePrivate::preferredFormat() const
{
    return doWithDeviceFormat([](const AudioDeviceFormat &fmt) {
        return fmt.preferredFormat;
    });
}
 
QAudioDeviceExpected<int> QAudioDevicePrivate::minimumSampleRate() const
{
    return doWithDeviceFormat([](const AudioDeviceFormat &fmt) {
        return fmt.minimumSampleRate;
    });
}
 
QAudioDeviceExpected<int> QAudioDevicePrivate::maximumSampleRate() const
{
    return doWithDeviceFormat([](const AudioDeviceFormat &fmt) {
        return fmt.maximumSampleRate;
    });
}
 
QAudioDeviceExpected<int> QAudioDevicePrivate::minimumChannelCount() const
{
    return doWithDeviceFormat([](const AudioDeviceFormat &fmt) {
        return fmt.minimumChannelCount;
    });
}
 
QAudioDeviceExpected<int> QAudioDevicePrivate::maximumChannelCount() const
{
    return doWithDeviceFormat([](const AudioDeviceFormat &fmt) {
        return fmt.maximumChannelCount;
    });
}
 
QAudioDeviceExpected<QList<QAudioFormat::SampleFormat>>
QAudioDevicePrivate::supportedSampleFormats() const
{
    return doWithDeviceFormat([](const AudioDeviceFormat &fmt) {
        return fmt.supportedSampleFormats;
    });
}
 
QAudioDeviceExpected<QAudioFormat::ChannelConfig> QAudioDevicePrivate::channelConfiguration() const
{
    return doWithDeviceFormat([](const AudioDeviceFormat &fmt) {
        return fmt.channelConfiguration;
    });
}
 
QAudioDeviceExpected<bool> QAudioDevicePrivate::isFormatSupported(const QAudioFormat &format) const
{
    return doWithDeviceFormat([&](const AudioDeviceFormat &deviceFormat) {
        if (format.sampleRate() < deviceFormat.minimumSampleRate
            || format.sampleRate() > deviceFormat.maximumSampleRate)
            return false;
        if (format.channelCount() < deviceFormat.minimumChannelCount
            || format.channelCount() > deviceFormat.maximumChannelCount)
            return false;
        if (!deviceFormat.supportedSampleFormats.contains(format.sampleFormat()))
            return false;
        return true;
    });
}
 
QAudioDevice
QAudioDevicePrivate::createQAudioDevice(std::unique_ptr<QAudioDevicePrivate> devicePrivate)
{
    return QAudioDevice(devicePrivate.release());
}
 
const QAudioDevicePrivate *QAudioDevicePrivate::handle(const QAudioDevice &device)
{
    return device.d.get();
}
 
QT_END_NAMESPACE
 
#include "moc_qaudiodevice.cpp"