godot/drivers/alsa/audio_driver_alsa.cpp
Rémi Verschelde a7f49ac9a1 Update copyright statements to 2020
Happy new year to the wonderful Godot community!

We're starting a new decade with a well-established, non-profit, free
and open source game engine, and tons of further improvements in the
pipeline from hundreds of contributors.

Godot will keep getting better, and we're looking forward to all the
games that the community will keep developing and releasing with it.
2020-01-01 11:16:22 +01:00

352 lines
9.4 KiB
C++

/*************************************************************************/
/* audio_driver_alsa.cpp */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2020 Juan Linietsky, Ariel Manzur. */
/* Copyright (c) 2014-2020 Godot Engine contributors (cf. AUTHORS.md). */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/*************************************************************************/
#include "audio_driver_alsa.h"
#ifdef ALSA_ENABLED
#include "core/os/os.h"
#include "core/project_settings.h"
#include <errno.h>
Error AudioDriverALSA::init_device() {
mix_rate = GLOBAL_DEF("audio/mix_rate", DEFAULT_MIX_RATE);
speaker_mode = SPEAKER_MODE_STEREO;
channels = 2;
// If there is a specified device check that it is really present
if (device_name != "Default") {
Array list = get_device_list();
if (list.find(device_name) == -1) {
device_name = "Default";
new_device = "Default";
}
}
int status;
snd_pcm_hw_params_t *hwparams;
snd_pcm_sw_params_t *swparams;
#define CHECK_FAIL(m_cond) \
if (m_cond) { \
fprintf(stderr, "ALSA ERR: %s\n", snd_strerror(status)); \
if (pcm_handle) { \
snd_pcm_close(pcm_handle); \
pcm_handle = NULL; \
} \
ERR_FAIL_COND_V(m_cond, ERR_CANT_OPEN); \
}
//todo, add
//6 chans - "plug:surround51"
//4 chans - "plug:surround40";
if (device_name == "Default") {
status = snd_pcm_open(&pcm_handle, "default", SND_PCM_STREAM_PLAYBACK, SND_PCM_NONBLOCK);
} else {
String device = device_name;
int pos = device.find(";");
if (pos != -1) {
device = device.substr(0, pos);
}
status = snd_pcm_open(&pcm_handle, device.utf8().get_data(), SND_PCM_STREAM_PLAYBACK, SND_PCM_NONBLOCK);
}
ERR_FAIL_COND_V(status < 0, ERR_CANT_OPEN);
snd_pcm_hw_params_alloca(&hwparams);
status = snd_pcm_hw_params_any(pcm_handle, hwparams);
CHECK_FAIL(status < 0);
status = snd_pcm_hw_params_set_access(pcm_handle, hwparams, SND_PCM_ACCESS_RW_INTERLEAVED);
CHECK_FAIL(status < 0);
//not interested in anything else
status = snd_pcm_hw_params_set_format(pcm_handle, hwparams, SND_PCM_FORMAT_S16_LE);
CHECK_FAIL(status < 0);
//todo: support 4 and 6
status = snd_pcm_hw_params_set_channels(pcm_handle, hwparams, 2);
CHECK_FAIL(status < 0);
status = snd_pcm_hw_params_set_rate_near(pcm_handle, hwparams, &mix_rate, NULL);
CHECK_FAIL(status < 0);
// In ALSA the period size seems to be the one that will determine the actual latency
// Ref: https://www.alsa-project.org/main/index.php/FramesPeriods
unsigned int periods = 2;
int latency = GLOBAL_DEF("audio/output_latency", DEFAULT_OUTPUT_LATENCY);
buffer_frames = closest_power_of_2(latency * mix_rate / 1000);
buffer_size = buffer_frames * periods;
period_size = buffer_frames;
// set buffer size from project settings
status = snd_pcm_hw_params_set_buffer_size_near(pcm_handle, hwparams, &buffer_size);
CHECK_FAIL(status < 0);
status = snd_pcm_hw_params_set_period_size_near(pcm_handle, hwparams, &period_size, NULL);
CHECK_FAIL(status < 0);
print_verbose("Audio buffer frames: " + itos(period_size) + " calculated latency: " + itos(period_size * 1000 / mix_rate) + "ms");
status = snd_pcm_hw_params_set_periods_near(pcm_handle, hwparams, &periods, NULL);
CHECK_FAIL(status < 0);
status = snd_pcm_hw_params(pcm_handle, hwparams);
CHECK_FAIL(status < 0);
//snd_pcm_hw_params_free(&hwparams);
snd_pcm_sw_params_alloca(&swparams);
status = snd_pcm_sw_params_current(pcm_handle, swparams);
CHECK_FAIL(status < 0);
status = snd_pcm_sw_params_set_avail_min(pcm_handle, swparams, period_size);
CHECK_FAIL(status < 0);
status = snd_pcm_sw_params_set_start_threshold(pcm_handle, swparams, 1);
CHECK_FAIL(status < 0);
status = snd_pcm_sw_params(pcm_handle, swparams);
CHECK_FAIL(status < 0);
samples_in.resize(period_size * channels);
samples_out.resize(period_size * channels);
return OK;
}
Error AudioDriverALSA::init() {
active = false;
thread_exited = false;
exit_thread = false;
Error err = init_device();
if (err == OK) {
mutex = Mutex::create();
thread = Thread::create(AudioDriverALSA::thread_func, this);
}
return err;
}
void AudioDriverALSA::thread_func(void *p_udata) {
AudioDriverALSA *ad = (AudioDriverALSA *)p_udata;
while (!ad->exit_thread) {
ad->lock();
ad->start_counting_ticks();
if (!ad->active) {
for (uint64_t i = 0; i < ad->period_size * ad->channels; i++) {
ad->samples_out.write[i] = 0;
}
} else {
ad->audio_server_process(ad->period_size, ad->samples_in.ptrw());
for (uint64_t i = 0; i < ad->period_size * ad->channels; i++) {
ad->samples_out.write[i] = ad->samples_in[i] >> 16;
}
}
int todo = ad->period_size;
int total = 0;
while (todo && !ad->exit_thread) {
uint8_t *src = (uint8_t *)ad->samples_out.ptr();
int wrote = snd_pcm_writei(ad->pcm_handle, (void *)(src + (total * ad->channels)), todo);
if (wrote > 0) {
total += wrote;
todo -= wrote;
} else if (wrote == -EAGAIN) {
ad->stop_counting_ticks();
ad->unlock();
OS::get_singleton()->delay_usec(1000);
ad->lock();
ad->start_counting_ticks();
} else {
wrote = snd_pcm_recover(ad->pcm_handle, wrote, 0);
if (wrote < 0) {
ERR_PRINTS("ALSA: Failed and can't recover: " + String(snd_strerror(wrote)));
ad->active = false;
ad->exit_thread = true;
}
}
}
// User selected a new device, finish the current one so we'll init the new device
if (ad->device_name != ad->new_device) {
ad->device_name = ad->new_device;
ad->finish_device();
Error err = ad->init_device();
if (err != OK) {
ERR_PRINT("ALSA: init_device error");
ad->device_name = "Default";
ad->new_device = "Default";
err = ad->init_device();
if (err != OK) {
ad->active = false;
ad->exit_thread = true;
}
}
}
ad->stop_counting_ticks();
ad->unlock();
}
ad->thread_exited = true;
}
void AudioDriverALSA::start() {
active = true;
}
int AudioDriverALSA::get_mix_rate() const {
return mix_rate;
}
AudioDriver::SpeakerMode AudioDriverALSA::get_speaker_mode() const {
return speaker_mode;
}
Array AudioDriverALSA::get_device_list() {
Array list;
list.push_back("Default");
void **hints;
if (snd_device_name_hint(-1, "pcm", &hints) < 0)
return list;
for (void **n = hints; *n != NULL; n++) {
char *name = snd_device_name_get_hint(*n, "NAME");
char *desc = snd_device_name_get_hint(*n, "DESC");
if (name != NULL && !strncmp(name, "plughw", 6)) {
if (desc) {
list.push_back(String(name) + ";" + String(desc));
} else {
list.push_back(String(name));
}
}
if (desc != NULL)
free(desc);
if (name != NULL)
free(name);
}
snd_device_name_free_hint(hints);
return list;
}
String AudioDriverALSA::get_device() {
return device_name;
}
void AudioDriverALSA::set_device(String device) {
lock();
new_device = device;
unlock();
}
void AudioDriverALSA::lock() {
if (!thread || !mutex)
return;
mutex->lock();
}
void AudioDriverALSA::unlock() {
if (!thread || !mutex)
return;
mutex->unlock();
}
void AudioDriverALSA::finish_device() {
if (pcm_handle) {
snd_pcm_close(pcm_handle);
pcm_handle = NULL;
}
}
void AudioDriverALSA::finish() {
if (thread) {
exit_thread = true;
Thread::wait_to_finish(thread);
memdelete(thread);
thread = NULL;
if (mutex) {
memdelete(mutex);
mutex = NULL;
}
}
finish_device();
}
AudioDriverALSA::AudioDriverALSA() :
thread(NULL),
mutex(NULL),
pcm_handle(NULL),
device_name("Default"),
new_device("Default") {
}
AudioDriverALSA::~AudioDriverALSA() {
}
#endif