mirror of https://github.com/bsnes-emu/bsnes.git
128 lines
3.2 KiB
C++
128 lines
3.2 KiB
C++
#include <unistd.h>
|
|
#include <fcntl.h>
|
|
#include <sys/ioctl.h>
|
|
#include <sys/soundcard.h>
|
|
|
|
//OSSv4 features: define fallbacks for OSSv3 (where these ioctls are ignored)
|
|
|
|
#ifndef SNDCTL_DSP_COOKEDMODE
|
|
#define SNDCTL_DSP_COOKEDMODE _IOW('P', 30, int)
|
|
#endif
|
|
|
|
#ifndef SNDCTL_DSP_POLICY
|
|
#define SNDCTL_DSP_POLICY _IOW('P', 45, int)
|
|
#endif
|
|
|
|
struct AudioOSS : Audio {
|
|
AudioOSS() { initialize(); }
|
|
~AudioOSS() { terminate(); }
|
|
|
|
auto ready() -> bool { return _ready; }
|
|
|
|
auto information() -> Information {
|
|
Information information;
|
|
information.devices = {"/dev/dsp"};
|
|
for(auto& device : directory::files("/dev/", "dsp?*")) information.devices.append(string{"/dev/", device});
|
|
information.frequencies = {44100.0, 48000.0, 96000.0};
|
|
information.latencies = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
|
|
information.channels = {1, 2};
|
|
return information;
|
|
}
|
|
|
|
auto device() -> string { return _device; }
|
|
auto blocking() -> bool { return _blocking; }
|
|
auto channels() -> uint { return _channels; }
|
|
auto frequency() -> double { return _frequency; }
|
|
auto latency() -> uint { return _latency; }
|
|
|
|
auto setDevice(string device) -> bool {
|
|
if(_device == device) return true;
|
|
_device = device;
|
|
return initialize();
|
|
}
|
|
|
|
auto setBlocking(bool blocking) -> bool {
|
|
if(_blocking == blocking) return true;
|
|
_blocking = blocking;
|
|
updateBlocking();
|
|
return true;
|
|
}
|
|
|
|
auto setChannels(uint channels) -> bool {
|
|
if(_channels == channels) return true;
|
|
_channels = channels;
|
|
return initialize();
|
|
}
|
|
|
|
auto setFrequency(double frequency) -> bool {
|
|
if(_frequency == frequency) return true;
|
|
_frequency = frequency;
|
|
return initialize();
|
|
}
|
|
|
|
auto setLatency(uint latency) -> bool {
|
|
if(_latency == latency) return true;
|
|
_latency = latency;
|
|
return initialize();
|
|
}
|
|
|
|
auto output(const double samples[]) -> void {
|
|
if(!ready()) return;
|
|
for(auto n : range(_channels)) {
|
|
int16_t sample = samples[n] * 32768.0;
|
|
auto unused = write(_fd, &sample, 2);
|
|
}
|
|
}
|
|
|
|
private:
|
|
auto initialize() -> bool {
|
|
terminate();
|
|
|
|
if(!information().devices.find(_device)) {
|
|
_device = information().devices.left();
|
|
}
|
|
|
|
_fd = open(_device, O_WRONLY, O_NONBLOCK);
|
|
if(_fd < 0) return false;
|
|
|
|
int cooked = 1;
|
|
ioctl(_fd, SNDCTL_DSP_COOKEDMODE, &cooked);
|
|
//policy: 0 = minimum latency (higher CPU usage); 10 = maximum latency (lower CPU usage)
|
|
int policy = min(10, _latency);
|
|
ioctl(_fd, SNDCTL_DSP_POLICY, &policy);
|
|
int channels = _channels;
|
|
ioctl(_fd, SNDCTL_DSP_CHANNELS, &channels);
|
|
ioctl(_fd, SNDCTL_DSP_SETFMT, &_format);
|
|
int frequency = _frequency;
|
|
ioctl(_fd, SNDCTL_DSP_SPEED, &frequency);
|
|
|
|
updateBlocking();
|
|
return _ready = true;
|
|
}
|
|
|
|
auto terminate() -> void {
|
|
_ready = false;
|
|
if(_fd < 0) return;
|
|
close(_fd);
|
|
_fd = -1;
|
|
}
|
|
|
|
auto updateBlocking() -> void {
|
|
if(!_ready) return;
|
|
auto flags = fcntl(_fd, F_GETFL);
|
|
if(flags < 0) return;
|
|
_blocking ? flags &=~ O_NONBLOCK : flags |= O_NONBLOCK;
|
|
fcntl(_fd, F_SETFL, flags);
|
|
}
|
|
|
|
bool _ready = false;
|
|
string _device;
|
|
bool _blocking = true;
|
|
uint _channels = 2;
|
|
double _frequency = 48000.0;
|
|
uint _latency = 2;
|
|
|
|
int _fd = -1;
|
|
int _format = AFMT_S16_LE;
|
|
};
|