qalsaaudiodevice.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
 
//
//  W A R N I N G
//  -------------
//
// This file is not part of the Qt API.  It exists for the convenience
// of other Qt classes.  This header file may change from version to
// version without notice, or even be removed.
//
// INTERNAL USE ONLY: Do NOT use for any other purpose.
//
 
#include "qalsaaudiodevice_p.h"
 
#include <alsa/version.h>
 
QT_BEGIN_NAMESPACE
 
QAlsaAudioDeviceInfo::QAlsaAudioDeviceInfo(const QByteArray &dev, const QString &desc, QAudioDevice::Mode mode)
    : QAudioDevicePrivate(dev, mode)
{
    description = desc;
 
    checkSurround();
 
    minimumChannelCount = 1;
    maximumChannelCount = 2;
    if (surround71)
        maximumChannelCount = 8;
    else if (surround40)
        maximumChannelCount = 4;
    else if (surround51)
        maximumChannelCount = 6;
 
    minimumSampleRate = 8000;
    maximumSampleRate = 48000;
 
    supportedSampleFormats << QAudioFormat::UInt8 << QAudioFormat::Int16 << QAudioFormat::Int32 << QAudioFormat::Float;
 
    preferredFormat.setChannelCount(mode == QAudioDevice::Input ? 1 : 2);
    preferredFormat.setSampleFormat(QAudioFormat::Float);
    preferredFormat.setSampleRate(48000);
}
 
QAlsaAudioDeviceInfo::~QAlsaAudioDeviceInfo()
{
}
 
void QAlsaAudioDeviceInfo::checkSurround()
{
    surround40 = false;
    surround51 = false;
    surround71 = false;
 
    void **hints, **n;
    char *name, *descr, *io;
 
    if(snd_device_name_hint(-1, "pcm", &hints) < 0)
        return;
 
    n = hints;
 
    while (*n != NULL) {
        name = snd_device_name_get_hint(*n, "NAME");
        descr = snd_device_name_get_hint(*n, "DESC");
        io = snd_device_name_get_hint(*n, "IOID");
        if((name != NULL) && (descr != NULL)) {
            QString deviceName = QLatin1String(name);
            if (mode == QAudioDevice::Output) {
                if(deviceName.contains(QLatin1String("surround40")))
                    surround40 = true;
                if(deviceName.contains(QLatin1String("surround51")))
                    surround51 = true;
                if(deviceName.contains(QLatin1String("surround71")))
                    surround71 = true;
            }
        }
        if(name != NULL)
            free(name);
        if(descr != NULL)
            free(descr);
        if(io != NULL)
            free(io);
        ++n;
    }
    snd_device_name_free_hint(hints);
}
 
QT_END_NAMESPACE