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#include "oss.h"
#include <sys/soundcard.h>
#include <fcntl.h>
#include <stdlib.h>
#include <unistd.h>
#include <iostream>
OSSOutputEngine::OSSOutputEngine()
: dev{"/dev/dsp"}
, num_channels{16}
, srate{44100}
, format{AFMT_S32_NE}
, data{}
{
data.clear();
data.resize(1024 * num_channels);
}
bool OSSOutputEngine::init(const Channels& channels)
{
int tmp, mode = O_WRONLY;
num_channels = channels.size();
if((fd = open(dev.data(), mode, 0)) == -1)
{
std::cerr << dev.data() << ' ' << std::strerror(errno) << std::endl;
return false;
}
tmp = format;
if(ioctl(fd, SNDCTL_DSP_SETFMT, &tmp) == -1 || tmp != format)
{
std::cerr << "Setting audio format failed " << std::strerror(errno);
std::cerr << std::endl;
return false;
}
tmp = num_channels;
if(ioctl(fd, SNDCTL_DSP_CHANNELS, &tmp) == -1 || tmp != num_channels)
{
std::cerr << "Can not set number of channels to " << num_channels;
std::cerr << ": " << std::strerror(errno) << std::endl;
return false;
}
tmp = srate;
if(ioctl(fd, SNDCTL_DSP_SPEED, &tmp) == -1 || tmp != srate)
{
std::cerr << "Can not set sampling frequency to " << srate << ": ";
std::cerr << std::strerror(errno) << std::endl;
return false;
}
return true;
}
void OSSOutputEngine::setParm(const std::string& parm, const std::string& value)
{
if(parm == "dev")
{
dev = value;
}
else if(parm == "srate")
{
try
{
srate = std::stoi(value);
}
catch(...)
{
std::cerr << "[OSSOutputEngine] Invalid samplerate ";
std::cerr << value << std::endl;
}
}
else
{
std::cerr << "[OSSOutputEngine] Unsupported parameter '";
std::cerr << parm << std::endl;
}
}
void OSSOutputEngine::run(int ch, sample_t* samples, size_t nsamples)
{
std::int32_t sample;
for(size_t i = 0; i < nsamples; ++i)
{
if(samples[i] > 1)
{
sample = INT32_MAX;
}
else if(samples[i] < -1)
{
sample = -INT32_MAX;
}
else
{
sample = samples[i] * INT32_MAX;
}
data[i * num_channels + ch] = sample;
}
}
void OSSOutputEngine::post(size_t nsamples)
{
auto data_size = data.size() * sizeof(*data.data());
auto size_written = write(fd, data.data(), data_size);
if(size_written != data_size)
{
std::cerr << "Audio write: " << std::strerror(errno) << std::endl;
}
}
std::size_t OSSOutputEngine::getBufferSize() const
{
return data.size() / num_channels;
}
std::size_t OSSOutputEngine::getSamplerate() const
{
return srate;
}
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