115 lines
3.3 KiB
C++
115 lines
3.3 KiB
C++
#include <unistd.h>
|
|
#include <fcntl.h>
|
|
#include <sys/ioctl.h>
|
|
#include <sys/soundcard.h>
|
|
|
|
//OSS4 soundcard.h includes below SNDCTL defines, but OSS3 does not
|
|
//However, OSS4 soundcard.h does not reside in <sys/>
|
|
//Therefore, attempt to manually define SNDCTL values if using OSS3 header
|
|
//Note that if the defines below fail to work on any specific platform, one can point soundcard.h
|
|
//above to the correct location for OSS4 (usually /usr/lib/oss/include/sys/soundcard.h)
|
|
//Failing that, one can disable OSS4 ioctl calls inside init() and remove the below defines
|
|
|
|
#ifndef SNDCTL_DSP_COOKEDMODE
|
|
#define SNDCTL_DSP_COOKEDMODE _IOW('P', 30, signed)
|
|
#endif
|
|
|
|
#ifndef SNDCTL_DSP_POLICY
|
|
#define SNDCTL_DSP_POLICY _IOW('P', 45, signed)
|
|
#endif
|
|
|
|
struct AudioOSS : Audio {
|
|
~AudioOSS() { term(); }
|
|
|
|
struct {
|
|
signed fd = -1;
|
|
signed format = AFMT_S16_LE;
|
|
signed channels = 2;
|
|
} device;
|
|
|
|
struct {
|
|
string device = "/dev/dsp";
|
|
bool synchronize = true;
|
|
unsigned frequency = 22050;
|
|
} settings;
|
|
|
|
auto cap(const string& name) -> bool {
|
|
if(name == Audio::Device) return true;
|
|
if(name == Audio::Synchronize) return true;
|
|
if(name == Audio::Frequency) return true;
|
|
return false;
|
|
}
|
|
|
|
auto get(const string& name) -> any {
|
|
if(name == Audio::Device) return settings.device;
|
|
if(name == Audio::Synchronize) return settings.synchronize;
|
|
if(name == Audio::Frequency) return settings.frequency;
|
|
return {};
|
|
}
|
|
|
|
auto set(const string& name, const any& value) -> bool {
|
|
if(name == Audio::Device && value.is<string>()) {
|
|
settings.device = value.get<string>();
|
|
if(!settings.device) settings.device = "/dev/dsp";
|
|
return true;
|
|
}
|
|
|
|
if(name == Audio::Synchronize && value.is<bool>()) {
|
|
settings.synchronize = value.get<bool>();
|
|
updateSynchronization();
|
|
return true;
|
|
}
|
|
|
|
if(name == Audio::Frequency && value.is<unsigned>()) {
|
|
settings.frequency = value.get<unsigned>();
|
|
if(device.fd >= 0) init();
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
auto sample(uint16_t left, uint16_t right) -> void {
|
|
uint32_t sample = left << 0 | right << 16;
|
|
auto unused = write(device.fd, &sample, 4);
|
|
}
|
|
|
|
auto clear() -> void {
|
|
}
|
|
|
|
auto init() -> bool {
|
|
device.fd = open(settings.device, O_WRONLY, O_NONBLOCK);
|
|
if(device.fd < 0) return false;
|
|
|
|
#if 1 //SOUND_VERSION >= 0x040000
|
|
//attempt to enable OSS4-specific features regardless of version
|
|
//OSS3 ioctl calls will silently fail, but sound will still work
|
|
signed cooked = 1, policy = 4; //policy should be 0 - 10, lower = less latency, more CPU usage
|
|
ioctl(device.fd, SNDCTL_DSP_COOKEDMODE, &cooked);
|
|
ioctl(device.fd, SNDCTL_DSP_POLICY, &policy);
|
|
#endif
|
|
signed freq = settings.frequency;
|
|
ioctl(device.fd, SNDCTL_DSP_CHANNELS, &device.channels);
|
|
ioctl(device.fd, SNDCTL_DSP_SETFMT, &device.format);
|
|
ioctl(device.fd, SNDCTL_DSP_SPEED, &freq);
|
|
|
|
updateSynchronization();
|
|
return true;
|
|
}
|
|
|
|
auto term() -> void {
|
|
if(device.fd >= 0) {
|
|
close(device.fd);
|
|
device.fd = -1;
|
|
}
|
|
}
|
|
|
|
private:
|
|
auto updateSynchronization() -> void {
|
|
if(device.fd < 0) return;
|
|
auto flags = fcntl(device.fd, F_GETFL);
|
|
if(flags < 0) return;
|
|
settings.synchronize ? flags &=~ O_NONBLOCK : flags |= O_NONBLOCK;
|
|
fcntl(device.fd, F_SETFL, flags);
|
|
}
|
|
};
|