Revision control
Copy as Markdown
// 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 <QtCore/qcoreapplication.h>
#include <QtCore/qvarlengtharray.h>
#include <QtMultimedia/private/qaudiohelpers_p.h>
#include "qalsaaudiosource_p.h"
QT_BEGIN_NAMESPACE
//#define DEBUG_AUDIO 1
QAlsaAudioSource::QAlsaAudioSource(QAudioDevice device, const QAudioFormat &fmt, QObject *parent)
: QPlatformAudioSource(std::move(device), fmt, parent)
{
bytesAvailable = 0;
handle = 0;
access = SND_PCM_ACCESS_RW_INTERLEAVED;
pcmformat = SND_PCM_FORMAT_S16;
buffer_size = 0;
period_size = 0;
buffer_time = 100000;
period_time = 20000;
totalTimeValue = 0;
deviceState = QAudio::StoppedState;
audioSource = 0;
pullMode = true;
resuming = false;
timer = new QTimer(this);
connect(timer, &QTimer::timeout, this, &QAlsaAudioSource::userFeed);
}
QAlsaAudioSource::~QAlsaAudioSource()
{
close();
disconnect(timer, &QTimer::timeout, this, &QAlsaAudioSource::userFeed);
delete timer;
}
QAudio::State QAlsaAudioSource::state() const
{
return deviceState;
}
int QAlsaAudioSource::xrun_recovery(int err)
{
int count = 0;
bool reset = false;
// ESTRPIPE is not available in all OSes where ALSA is available
int estrpipe = EIO;
#ifdef ESTRPIPE
estrpipe = ESTRPIPE;
#endif
if(err == -EPIPE) {
setError(QAudio::UnderrunError);
err = snd_pcm_prepare(handle);
if(err < 0)
reset = true;
else {
bytesAvailable = checkBytesReady();
if (bytesAvailable <= 0)
reset = true;
}
} else if ((err == -estrpipe)||(err == -EIO)) {
setError(QAudio::IOError);
while((err = snd_pcm_resume(handle)) == -EAGAIN){
usleep(100);
count++;
if(count > 5) {
reset = true;
break;
}
}
if(err < 0) {
err = snd_pcm_prepare(handle);
if(err < 0)
reset = true;
}
}
if(reset) {
close();
open();
snd_pcm_prepare(handle);
return 0;
}
return err;
}
int QAlsaAudioSource::setFormat()
{
snd_pcm_format_t pcmformat = SND_PCM_FORMAT_UNKNOWN;
switch (m_format.sampleFormat()) {
case QAudioFormat::UInt8:
pcmformat = SND_PCM_FORMAT_U8;
break;
case QAudioFormat::Int16:
if constexpr (QSysInfo::ByteOrder == QSysInfo::BigEndian)
pcmformat = SND_PCM_FORMAT_S16_BE;
else
pcmformat = SND_PCM_FORMAT_S16_LE;
break;
case QAudioFormat::Int32:
if constexpr (QSysInfo::ByteOrder == QSysInfo::BigEndian)
pcmformat = SND_PCM_FORMAT_S32_BE;
else
pcmformat = SND_PCM_FORMAT_S32_LE;
break;
case QAudioFormat::Float:
if constexpr (QSysInfo::ByteOrder == QSysInfo::BigEndian)
pcmformat = SND_PCM_FORMAT_FLOAT_BE;
else
pcmformat = SND_PCM_FORMAT_FLOAT_LE;
break;
default:
break;
}
return pcmformat != SND_PCM_FORMAT_UNKNOWN
? snd_pcm_hw_params_set_format( handle, hwparams, pcmformat)
: -1;
}
void QAlsaAudioSource::start(QIODevice* device)
{
if(deviceState != QAudio::StoppedState)
close();
if(!pullMode && audioSource)
delete audioSource;
pullMode = true;
audioSource = device;
deviceState = QAudio::ActiveState;
if( !open() )
return;
Q_EMIT stateChanged(deviceState);
}
QIODevice* QAlsaAudioSource::start()
{
if(deviceState != QAudio::StoppedState)
close();
if(!pullMode && audioSource)
delete audioSource;
pullMode = false;
audioSource = new AlsaInputPrivate(this);
audioSource->open(QIODevice::ReadOnly | QIODevice::Unbuffered);
deviceState = QAudio::IdleState;
if( !open() )
return 0;
Q_EMIT stateChanged(deviceState);
return audioSource;
}
void QAlsaAudioSource::stop()
{
if(deviceState == QAudio::StoppedState)
return;
deviceState = QAudio::StoppedState;
close();
Q_EMIT stateChanged(deviceState);
}
bool QAlsaAudioSource::open()
{
#ifdef DEBUG_AUDIO
QTime now(QTime::currentTime());
qDebug()<<now.second()<<"s "<<now.msec()<<"ms :open()";
#endif
elapsedTimeOffset = 0;
int dir;
int err = -1;
int count=0;
unsigned int sampleRate=m_format.sampleRate();
// Step 1: try and open the device
while((count < 5) && (err < 0)) {
err = snd_pcm_open(&handle, m_audioDevice.id().constData(), SND_PCM_STREAM_CAPTURE, 0);
if(err < 0)
count++;
}
if (( err < 0)||(handle == 0)) {
setError(QAudio::OpenError);
deviceState = QAudio::StoppedState;
Q_EMIT stateChanged(deviceState);
return false;
}
snd_pcm_nonblock( handle, 0 );
// Step 2: Set the desired HW parameters.
snd_pcm_hw_params_alloca( &hwparams );
bool fatal = false;
QString errMessage;
unsigned int chunks = 8;
err = snd_pcm_hw_params_any( handle, hwparams );
if ( err < 0 ) {
fatal = true;
errMessage = QString::fromLatin1("QAudioSource: snd_pcm_hw_params_any: err = %1").arg(err);
}
if ( !fatal ) {
err = snd_pcm_hw_params_set_rate_resample( handle, hwparams, 1 );
if ( err < 0 ) {
fatal = true;
errMessage = QString::fromLatin1("QAudioSource: snd_pcm_hw_params_set_rate_resample: err = %1").arg(err);
}
}
if ( !fatal ) {
err = snd_pcm_hw_params_set_access( handle, hwparams, access );
if ( err < 0 ) {
fatal = true;
errMessage = QString::fromLatin1("QAudioSource: snd_pcm_hw_params_set_access: err = %1").arg(err);
}
}
if ( !fatal ) {
err = setFormat();
if ( err < 0 ) {
fatal = true;
errMessage = QString::fromLatin1("QAudioSource: snd_pcm_hw_params_set_format: err = %1").arg(err);
}
}
if ( !fatal ) {
err = snd_pcm_hw_params_set_channels( handle, hwparams, (unsigned int)m_format.channelCount() );
if ( err < 0 ) {
fatal = true;
errMessage = QString::fromLatin1("QAudioSource: snd_pcm_hw_params_set_channels: err = %1").arg(err);
}
}
if ( !fatal ) {
err = snd_pcm_hw_params_set_rate_near( handle, hwparams, &sampleRate, 0 );
if ( err < 0 ) {
fatal = true;
errMessage = QString::fromLatin1("QAudioSource: snd_pcm_hw_params_set_rate_near: err = %1").arg(err);
}
}
if ( !fatal ) {
err = snd_pcm_hw_params_set_buffer_time_near(handle, hwparams, &buffer_time, &dir);
if ( err < 0 ) {
fatal = true;
errMessage = QString::fromLatin1("QAudioSource: snd_pcm_hw_params_set_buffer_time_near: err = %1").arg(err);
}
}
if ( !fatal ) {
err = snd_pcm_hw_params_set_period_time_near(handle, hwparams, &period_time, &dir);
if ( err < 0 ) {
fatal = true;
errMessage = QString::fromLatin1("QAudioSource: snd_pcm_hw_params_set_period_time_near: err = %1").arg(err);
}
}
if ( !fatal ) {
err = snd_pcm_hw_params_set_periods_near(handle, hwparams, &chunks, &dir);
if ( err < 0 ) {
fatal = true;
errMessage = QString::fromLatin1("QAudioSource: snd_pcm_hw_params_set_periods_near: err = %1").arg(err);
}
}
if ( !fatal ) {
err = snd_pcm_hw_params(handle, hwparams);
if ( err < 0 ) {
fatal = true;
errMessage = QString::fromLatin1("QAudioSource: snd_pcm_hw_params: err = %1").arg(err);
}
}
if( err < 0) {
qWarning()<<errMessage;
setError(QAudio::OpenError);
deviceState = QAudio::StoppedState;
Q_EMIT stateChanged(deviceState);
return false;
}
snd_pcm_hw_params_get_buffer_size(hwparams,&buffer_frames);
buffer_size = snd_pcm_frames_to_bytes(handle,buffer_frames);
snd_pcm_hw_params_get_period_size(hwparams,&period_frames, &dir);
period_size = snd_pcm_frames_to_bytes(handle,period_frames);
snd_pcm_hw_params_get_buffer_time(hwparams,&buffer_time, &dir);
snd_pcm_hw_params_get_period_time(hwparams,&period_time, &dir);
// Step 3: Set the desired SW parameters.
snd_pcm_sw_params_t *swparams;
snd_pcm_sw_params_alloca(&swparams);
snd_pcm_sw_params_current(handle, swparams);
snd_pcm_sw_params_set_start_threshold(handle,swparams,period_frames);
snd_pcm_sw_params_set_stop_threshold(handle,swparams,buffer_frames);
snd_pcm_sw_params_set_avail_min(handle, swparams,period_frames);
snd_pcm_sw_params(handle, swparams);
// Step 4: Prepare audio
ringBuffer.resize(buffer_size);
snd_pcm_prepare( handle );
snd_pcm_start(handle);
// Step 5: Setup timer
bytesAvailable = checkBytesReady();
if(pullMode)
connect(audioSource, &QIODevice::readyRead, this, &QAlsaAudioSource::userFeed);
// Step 6: Start audio processing
chunks = buffer_size/period_size;
timer->start(period_time*chunks/2000);
setError(QAudio::NoError);
totalTimeValue = 0;
return true;
}
void QAlsaAudioSource::close()
{
timer->stop();
if ( handle ) {
snd_pcm_drop( handle );
snd_pcm_close( handle );
handle = 0;
}
}
int QAlsaAudioSource::checkBytesReady()
{
if(resuming)
bytesAvailable = period_size;
else if(deviceState != QAudio::ActiveState
&& deviceState != QAudio::IdleState)
bytesAvailable = 0;
else {
int frames = snd_pcm_avail_update(handle);
if (frames < 0) {
bytesAvailable = frames;
} else {
if((int)frames > (int)buffer_frames)
frames = buffer_frames;
bytesAvailable = snd_pcm_frames_to_bytes(handle, frames);
}
}
return bytesAvailable;
}
qsizetype QAlsaAudioSource::bytesReady() const
{
return qMax(bytesAvailable, 0);
}
qint64 QAlsaAudioSource::read(char* data, qint64 len)
{
// Read in some audio data and write it to QIODevice, pull mode
if ( !handle )
return 0;
int bytesRead = 0;
int bytesInRingbufferBeforeRead = ringBuffer.bytesOfDataInBuffer();
if (ringBuffer.bytesOfDataInBuffer() < len) {
// bytesAvaiable is saved as a side effect of checkBytesReady().
int bytesToRead = checkBytesReady();
if (bytesToRead < 0) {
// bytesAvailable as negative is error code, try to recover from it.
xrun_recovery(bytesToRead);
bytesToRead = checkBytesReady();
if (bytesToRead < 0) {
// recovery failed must stop and set error.
close();
setError(QAudio::IOError);
deviceState = QAudio::StoppedState;
Q_EMIT stateChanged(deviceState);
return 0;
}
}
bytesToRead = qMin<qint64>(len, bytesToRead);
bytesToRead = qMin<qint64>(ringBuffer.freeBytes(), bytesToRead);
bytesToRead -= bytesToRead % period_size;
int count=0;
int err = 0;
QVarLengthArray<char, 4096> buffer(bytesToRead);
while(count < 5 && bytesToRead > 0) {
int chunks = bytesToRead / period_size;
int frames = chunks * period_frames;
if (frames > (int)buffer_frames)
frames = buffer_frames;
int readFrames = snd_pcm_readi(handle, buffer.data(), frames);
bytesRead = snd_pcm_frames_to_bytes(handle, readFrames);
if (volume() < 1.0f)
QAudioHelperInternal::qMultiplySamples(volume(), m_format, buffer.constData(),
buffer.data(), bytesRead);
if (readFrames >= 0) {
ringBuffer.write(buffer.data(), bytesRead);
#ifdef DEBUG_AUDIO
qDebug() << QString::fromLatin1("read in bytes = %1 (frames=%2)").arg(bytesRead).arg(readFrames).toLatin1().constData();
#endif
break;
} else if((readFrames == -EAGAIN) || (readFrames == -EINTR)) {
setError(QAudio::IOError);
err = 0;
break;
} else {
if(readFrames == -EPIPE) {
setError(QAudio::UnderrunError);
err = snd_pcm_prepare(handle);
#ifdef ESTRPIPE
} else if(readFrames == -ESTRPIPE) {
err = snd_pcm_prepare(handle);
#endif
}
if(err != 0) break;
}
count++;
}
}
bytesRead += bytesInRingbufferBeforeRead;
if (bytesRead > 0) {
// got some send it onward
#ifdef DEBUG_AUDIO
qDebug() << "frames to write to QIODevice = " <<
snd_pcm_bytes_to_frames( handle, (int)bytesRead ) << " (" << bytesRead << ") bytes";
#endif
if (deviceState != QAudio::ActiveState && deviceState != QAudio::IdleState)
return 0;
if (pullMode) {
qint64 l = 0;
qint64 bytesWritten = 0;
while (ringBuffer.bytesOfDataInBuffer() > 0) {
l = audioSource->write(ringBuffer.availableData(), ringBuffer.availableDataBlockSize());
if (l > 0) {
ringBuffer.readBytes(l);
bytesWritten += l;
} else {
break;
}
}
if (l < 0) {
close();
setError(QAudio::IOError);
deviceState = QAudio::StoppedState;
Q_EMIT stateChanged(deviceState);
} else if (l == 0 && bytesWritten == 0) {
if (deviceState != QAudio::IdleState) {
setError(QAudio::NoError);
deviceState = QAudio::IdleState;
Q_EMIT stateChanged(deviceState);
}
} else {
bytesAvailable -= bytesWritten;
totalTimeValue += bytesWritten;
resuming = false;
if (deviceState != QAudio::ActiveState) {
setError(QAudio::NoError);
deviceState = QAudio::ActiveState;
Q_EMIT stateChanged(deviceState);
}
}
return bytesWritten;
} else {
while (ringBuffer.bytesOfDataInBuffer() > 0) {
int size = ringBuffer.availableDataBlockSize();
memcpy(data, ringBuffer.availableData(), size);
data += size;
ringBuffer.readBytes(size);
}
bytesAvailable -= bytesRead;
totalTimeValue += bytesRead;
resuming = false;
if (deviceState != QAudio::ActiveState) {
setError(QAudio::NoError);
deviceState = QAudio::ActiveState;
Q_EMIT stateChanged(deviceState);
}
return bytesRead;
}
}
return 0;
}
void QAlsaAudioSource::resume()
{
if(deviceState == QAudio::SuspendedState) {
int err = 0;
if(handle) {
err = snd_pcm_prepare( handle );
if(err < 0)
xrun_recovery(err);
err = snd_pcm_start(handle);
if(err < 0)
xrun_recovery(err);
bytesAvailable = buffer_size;
}
resuming = true;
deviceState = QAudio::ActiveState;
int chunks = buffer_size/period_size;
timer->start(period_time*chunks/2000);
Q_EMIT stateChanged(deviceState);
}
}
void QAlsaAudioSource::setBufferSize(qsizetype value)
{
buffer_size = value;
}
qsizetype QAlsaAudioSource::bufferSize() const
{
return buffer_size;
}
qint64 QAlsaAudioSource::processedUSecs() const
{
qint64 result = qint64(1000000) * totalTimeValue /
m_format.bytesPerFrame() /
m_format.sampleRate();
return result;
}
void QAlsaAudioSource::suspend()
{
if(deviceState == QAudio::ActiveState||resuming) {
snd_pcm_drain(handle);
timer->stop();
deviceState = QAudio::SuspendedState;
Q_EMIT stateChanged(deviceState);
}
}
void QAlsaAudioSource::userFeed()
{
if(deviceState == QAudio::StoppedState || deviceState == QAudio::SuspendedState)
return;
#ifdef DEBUG_AUDIO
QTime now(QTime::currentTime());
qDebug()<<now.second()<<"s "<<now.msec()<<"ms :userFeed() IN";
#endif
deviceReady();
}
bool QAlsaAudioSource::deviceReady()
{
if(pullMode) {
// reads some audio data and writes it to QIODevice
read(0, buffer_size);
} else {
// emits readyRead() so user will call read() on QIODevice to get some audio data
AlsaInputPrivate* a = qobject_cast<AlsaInputPrivate*>(audioSource);
a->trigger();
}
bytesAvailable = checkBytesReady();
if(deviceState != QAudio::ActiveState)
return true;
if (bytesAvailable < 0) {
// bytesAvailable as negative is error code, try to recover from it.
xrun_recovery(bytesAvailable);
bytesAvailable = checkBytesReady();
if (bytesAvailable < 0) {
// recovery failed must stop and set error.
close();
setError(QAudio::IOError);
deviceState = QAudio::StoppedState;
Q_EMIT stateChanged(deviceState);
return 0;
}
}
return true;
}
void QAlsaAudioSource::reset()
{
if(handle)
snd_pcm_reset(handle);
stop();
bytesAvailable = 0;
}
void QAlsaAudioSource::drain()
{
if(handle)
snd_pcm_drain(handle);
}
AlsaInputPrivate::AlsaInputPrivate(QAlsaAudioSource* audio)
{
audioDevice = qobject_cast<QAlsaAudioSource*>(audio);
}
AlsaInputPrivate::~AlsaInputPrivate()
{
}
qint64 AlsaInputPrivate::readData( char* data, qint64 len)
{
return audioDevice->read(data,len);
}
qint64 AlsaInputPrivate::writeData(const char* data, qint64 len)
{
Q_UNUSED(data);
Q_UNUSED(len);
return 0;
}
void AlsaInputPrivate::trigger()
{
Q_EMIT readyRead();
}
RingBuffer::RingBuffer() :
m_head(0),
m_tail(0)
{
}
void RingBuffer::resize(int size)
{
m_data.resize(size);
}
int RingBuffer::bytesOfDataInBuffer() const
{
if (m_head < m_tail)
return m_tail - m_head;
else if (m_tail < m_head)
return m_data.size() + m_tail - m_head;
else
return 0;
}
int RingBuffer::freeBytes() const
{
if (m_head > m_tail)
return m_head - m_tail - 1;
else if (m_tail > m_head)
return m_data.size() - m_tail + m_head - 1;
else
return m_data.size() - 1;
}
const char *RingBuffer::availableData() const
{
return (m_data.constData() + m_head);
}
int RingBuffer::availableDataBlockSize() const
{
if (m_head > m_tail)
return m_data.size() - m_head;
else if (m_tail > m_head)
return m_tail - m_head;
else
return 0;
}
void RingBuffer::readBytes(int bytes)
{
m_head = (m_head + bytes) % m_data.size();
}
void RingBuffer::write(char *data, int len)
{
if (m_tail + len < m_data.size()) {
memcpy(m_data.data() + m_tail, data, len);
m_tail += len;
} else {
int bytesUntilEnd = m_data.size() - m_tail;
memcpy(m_data.data() + m_tail, data, bytesUntilEnd);
if (len - bytesUntilEnd > 0)
memcpy(m_data.data(), data + bytesUntilEnd, len - bytesUntilEnd);
m_tail = len - bytesUntilEnd;
}
}
QT_END_NAMESPACE
#include "moc_qalsaaudiosource_p.cpp"