AkAudioCaps AudioDevOSS::deviceCaps(const QString &device, int *fragmentSize) const
{
QFile pcmFile(QString(device)
.remove(QRegExp(":Input$|:Output$")));
if (!pcmFile.open(device.endsWith(":Input")?
QIODevice::ReadOnly: QIODevice::WriteOnly))
return AkAudioCaps();
int formats = AFMT_QUERY;
if (ioctl(pcmFile.handle(), SNDCTL_DSP_GETFMTS, &formats) < 0)
goto deviceCaps_fail;
static const QVector<int> preferredFormats = {
AFMT_S16_NE,
AFMT_S16_LE,
AFMT_S16_BE,
AFMT_U16_LE,
AFMT_U16_BE,
AFMT_S8,
AFMT_U8
};
int format;
format = AFMT_QUERY;
for (const auto &fmt: preferredFormats)
if (formats & fmt) {
format = fmt;
break;
}
if (format == AFMT_QUERY)
goto deviceCaps_fail;
if (ioctl(pcmFile.handle(), SNDCTL_DSP_SETFMT, &format) < 0)
goto deviceCaps_fail;
int stereo;
stereo = 1;
if (ioctl(pcmFile.handle(), SNDCTL_DSP_STEREO, &stereo) < 0)
goto deviceCaps_fail;
static const QVector<int> preferredSampleRates {
48000,
44100,
22050,
11025,
8000
};
int sampleRate;
sampleRate = 0;
for (int rate: preferredSampleRates)
if (ioctl(pcmFile.handle(), SNDCTL_DSP_SPEED, &rate) >= 0){
sampleRate = rate;
break;
}
if (sampleRate < 1)
goto deviceCaps_fail;
int channels;
channels = stereo? 2: 1;
AkAudioCaps::SampleFormat sampleFormat;
sampleFormat = sampleFormats->key(format,
AkAudioCaps::SampleFormat_none);
if (fragmentSize
&& device.endsWith(":Output")) {
// Set the buffer to a maximum of 1024 samples.
int bufferSize;
bufferSize = BUFFER_SIZE
* channels
* AkAudioCaps::bitsPerSample(sampleFormat)
/ 8;
// Let's try setting the fragmet to just 2 pieces, and the half of the
// buffer size, for low latency.
int fragment;
fragment = (2 << 16) | (bufferSize / 2);
ioctl(pcmFile.handle(), SNDCTL_DSP_SETFRAGMENT, &fragment);
// Let's see what OSS did actually set,
audio_buf_info info;
ioctl(pcmFile.handle(), SNDCTL_DSP_GETOSPACE, &info);
*fragmentSize = info.fragsize > 0?
((bufferSize / info.fragsize) << 16) | info.fragsize:
0;
}
pcmFile.close();
{
AkAudioCaps audioCaps;
audioCaps.isValid() = true;
audioCaps.format() = sampleFormat;
audioCaps.bps() = AkAudioCaps::bitsPerSample(audioCaps.format());
audioCaps.channels() = channels;
audioCaps.rate() = int(sampleRate);
audioCaps.layout() = AkAudioCaps::defaultChannelLayout(audioCaps.channels());
audioCaps.align() = false;
return audioCaps;
}
deviceCaps_fail:
pcmFile.close();
return AkAudioCaps();
}
AudioDevJack::AudioDevJack(QObject *parent):
AudioDev(parent)
{
this->m_curChannels = 0;
this->m_curSampleRate = 0;
this->m_maxBufferSize = 0;
this->m_isInput = false;
this->m_client = NULL;
this->m_descriptions = {
{":jackinput:" , "JACK Audio Connection Kit Input" },
{":jackoutput:", "JACK Audio Connection Kit Output"},
};
auto appName = QCoreApplication::applicationName()
+ QString("_%1").arg(Ak::id());
int maxNameSize = jack_client_name_size() - 1;
if (appName.size() > maxNameSize)
appName = appName.mid(0, maxNameSize);
jack_status_t status;
this->m_client = jack_client_open(appName.toStdString().c_str(),
JackNullOption,
&status);
if (!this->m_client) {
this->m_error = jackErrorCodes->value(status);
Q_EMIT this->errorChanged(this->m_error);
return;
}
// Setup callbacks
jack_set_process_callback(this->m_client,
AudioDevJack::onProcessCallback,
this);
jack_on_shutdown(this->m_client,
AudioDevJack::onShutdownCallback,
this);
AkAudioCaps audioCaps;
audioCaps.isValid() = true;
audioCaps.format() = AkAudioCaps::SampleFormat_flt;
audioCaps.bps() = AkAudioCaps::bitsPerSample(audioCaps.format());
audioCaps.rate() = int(jack_get_sample_rate(this->m_client));
audioCaps.layout() = AkAudioCaps::defaultChannelLayout(audioCaps.channels());
audioCaps.align() = false;
QMap<QString, JackPortFlags> portTypeMap = {
{":jackinput:" , JackPortIsOutput},
{":jackoutput:", JackPortIsInput }
};
// Query the number orr channels
for (auto deviceId: portTypeMap.keys()) {
auto ports = jack_get_ports(this->m_client,
NULL,
JACK_DEFAULT_AUDIO_TYPE,
JackPortIsPhysical | portTypeMap[deviceId]);
int channels = 0;
for (auto portName = ports; portName && *portName; portName++, channels++)
this->m_devicePorts[deviceId] << *portName;
if (ports)
jack_free(ports);
if (channels > 0) {
audioCaps.channels() = channels;
this->m_caps[deviceId] = audioCaps;
}
}
}
