bsnes/ruby/audio/alsa.cpp
Tim Allen afa8ea61c5 Update to v104r06 release.
byuu says:

Changelog:

  - gba,ws: removed Thread::step() override¹
  - processor/m68k: move.b (a7)+ and move.b (a7)- adjust a7 by two, not
    by one²
  - tomoko: created new initialize(Video,Audio,Input)Driver() functions³
  - ruby/audio: split Audio::information into
    Audio::available(Devices,Frequencies,Latencies,Channels)³
  - ws: added Model::(WonderSwan,WonderSwanColor,SwanCrystal)()
    functions for consistency with other cores

¹: this should hopefully fix GBA Pokemon Pinball. Thanks to
SuperMikeMan for pointing out the underlying cause.

²: this fixes A Ressaha de Ikou, Mega Bomberman, and probably more
games.

³: this is the big change: so there was a problem with WASAPI where
you might change your device under the audio settings panel. And your
new device may not support the frequency that your old device used. This
would end up not updating the frequency, and the pitch would be
distorted.

The old Audio::information() couldn't tell you what frequencies,
latencies, or channels were available for all devices simultaneously, so
I had to split them up. The new initializeAudioDriver() function
validates you have a correct driver, or it defaults to none. Then it
validates a correct device name, or it defaults to the first entry in
the list. Then it validates a correct frequency, or defaults to the
first in the list. Then finally it validates a correct latency, or
defaults to the first in the list.

In this way ... we have a clear path now with no API changes required to
select default devices, frequencies, latencies, channel counts: they
need to be the first items in their respective lists.

So, what we need to do now is go through and for every audio driver that
enumerates devices, we need to make sure the default device gets added
to the top of the list. I'm ... not really sure how to do this with most
drivers, so this is definitely going to take some time.

Also, when you change a device, initializeAudioDriver() is called again,
so if it's a bad device, it will disable the audio driver instead of
continuing to send samples at it and hoping that the driver blocked
those API calls when it failed to initialize properly.

Now then ... since it was a decently-sized API change, it's possible
I've broken compilation of the Linux drivers, so please report any
compilation errors so that I can fix them.
2017-08-26 11:15:49 +10:00

182 lines
5.2 KiB
C++

#include <alsa/asoundlib.h>
struct AudioALSA : Audio {
AudioALSA() { initialize(); }
~AudioALSA() { terminate(); }
auto availableDevices() -> string_vector {
return queryDevices();
}
auto availableFrequencies() -> vector<double> {
return {44100.0, 48000.0, 96000.0};
}
auto availableLatencies() -> vector<uint> {
return {20, 40, 60, 80, 100};
}
auto availableChannels() -> vector<uint> {
return {2};
}
auto ready() -> bool { return _ready; }
auto device() -> string { return _device; }
auto blocking() -> bool { return _blocking; }
auto channels() -> uint { return 2; }
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;
return true;
}
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;
_buffer[_offset++] = uint16_t(samples[0] * 32768.0) << 0 | uint16_t(samples[1] * 32768.0) << 16;
if(_offset < _periodSize) return;
snd_pcm_sframes_t available;
do {
available = snd_pcm_avail_update(_interface);
if(available < 0) snd_pcm_recover(_interface, available, 1);
if(available < _offset) {
if(!_blocking) {
_offset = 0;
return;
}
int error = snd_pcm_wait(_interface, -1);
if(error < 0) snd_pcm_recover(_interface, error, 1);
}
} while(available < _offset);
uint32_t* output = _buffer;
int i = 4;
while(_offset > 0 && i--) {
snd_pcm_sframes_t written = snd_pcm_writei(_interface, output, _offset);
if(written < 0) {
//no samples written
snd_pcm_recover(_interface, written, 1);
} else if(written <= _offset) {
_offset -= written;
output += written;
}
}
if(i < 0) {
if(_buffer == output) {
_offset--;
output++;
}
memory::move(_buffer, output, _offset * sizeof(uint32_t));
}
}
private:
auto initialize() -> bool {
terminate();
string device = "default";
if(queryDevices().find(_device)) device = _device;
if(snd_pcm_open(&_interface, device, SND_PCM_STREAM_PLAYBACK, SND_PCM_NONBLOCK) < 0) return terminate(), false;
uint rate = (uint)_frequency;
uint bufferTime = _latency * 1000;
uint periodTime = _latency * 1000 / 4;
snd_pcm_hw_params_t* hardwareParameters;
snd_pcm_hw_params_alloca(&hardwareParameters);
if(snd_pcm_hw_params_any(_interface, hardwareParameters) < 0) return terminate(), false;
if(snd_pcm_hw_params_set_access(_interface, hardwareParameters, SND_PCM_ACCESS_RW_INTERLEAVED) < 0
|| snd_pcm_hw_params_set_format(_interface, hardwareParameters, SND_PCM_FORMAT_S16_LE) < 0
|| snd_pcm_hw_params_set_channels(_interface, hardwareParameters, 2) < 0
|| snd_pcm_hw_params_set_rate_near(_interface, hardwareParameters, &rate, 0) < 0
|| snd_pcm_hw_params_set_period_time_near(_interface, hardwareParameters, &periodTime, 0) < 0
|| snd_pcm_hw_params_set_buffer_time_near(_interface, hardwareParameters, &bufferTime, 0) < 0
) return terminate(), false;
if(snd_pcm_hw_params(_interface, hardwareParameters) < 0) return terminate(), false;
if(snd_pcm_get_params(_interface, &_bufferSize, &_periodSize) < 0) return terminate(), false;
snd_pcm_sw_params_t* softwareParameters;
snd_pcm_sw_params_alloca(&softwareParameters);
if(snd_pcm_sw_params_current(_interface, softwareParameters) < 0) return terminate(), false;
if(snd_pcm_sw_params_set_start_threshold(_interface, softwareParameters,
(_bufferSize / _periodSize) * _periodSize) < 0
) return terminate(), false;
if(snd_pcm_sw_params(_interface, softwareParameters) < 0) return terminate(), false;
_buffer = new uint32_t[_periodSize]();
_offset = 0;
return _ready = true;
}
auto terminate() -> void {
_ready = false;
if(_interface) {
//snd_pcm_drain(_interface); //prevents popping noise; but causes multi-second lag
snd_pcm_close(_interface);
_interface = nullptr;
}
if(_buffer) {
delete[] _buffer;
_buffer = nullptr;
}
}
auto queryDevices() -> string_vector {
string_vector devices;
char** list;
if(snd_device_name_hint(-1, "pcm", (void***)&list) == 0) {
uint index = 0;
while(list[index]) {
char* deviceName = snd_device_name_get_hint(list[index], "NAME");
if(deviceName) devices.append(deviceName);
free(deviceName);
index++;
}
}
snd_device_name_free_hint((void**)list);
return devices;
}
bool _ready = false;
string _device;
bool _blocking = true;
double _frequency = 48000.0;
uint _latency = 40;
snd_pcm_t* _interface = nullptr;
snd_pcm_uframes_t _bufferSize;
snd_pcm_uframes_t _periodSize;
uint32_t* _buffer = nullptr;
uint _offset = 0;
};