qemu/audio/sdlaudio.c

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/*
* QEMU SDL audio output driver
*
* Copyright (c) 2004 Vassili Karpov (malc)
*
* 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 <SDL/SDL.h>
#include <SDL/SDL_thread.h>
#include "vl.h"
#define AUDIO_CAP "sdl"
#include "audio/audio.h"
#include "audio/sdlaudio.h"
#define QC_SDL_SAMPLES "QEMU_SDL_SAMPLES"
#define errstr() SDL_GetError ()
static struct {
int nb_samples;
} conf = {
1024
};
struct SDLAudioState {
int exit;
SDL_mutex *mutex;
SDL_sem *sem;
int initialized;
} glob_sdl;
typedef struct SDLAudioState SDLAudioState;
static void sdl_hw_run (HWVoice *hw)
{
(void) hw;
}
static int sdl_lock (SDLAudioState *s)
{
if (SDL_LockMutex (s->mutex)) {
dolog ("SDL_LockMutex failed\nReason: %s\n", errstr ());
return -1;
}
return 0;
}
static int sdl_unlock (SDLAudioState *s)
{
if (SDL_UnlockMutex (s->mutex)) {
dolog ("SDL_UnlockMutex failed\nReason: %s\n", errstr ());
return -1;
}
return 0;
}
static int sdl_post (SDLAudioState *s)
{
if (SDL_SemPost (s->sem)) {
dolog ("SDL_SemPost failed\nReason: %s\n", errstr ());
return -1;
}
return 0;
}
static int sdl_wait (SDLAudioState *s)
{
if (SDL_SemWait (s->sem)) {
dolog ("SDL_SemWait failed\nReason: %s\n", errstr ());
return -1;
}
return 0;
}
static int sdl_unlock_and_post (SDLAudioState *s)
{
if (sdl_unlock (s))
return -1;
return sdl_post (s);
}
static int sdl_hw_write (SWVoice *sw, void *buf, int len)
{
int ret;
SDLAudioState *s = &glob_sdl;
sdl_lock (s);
ret = pcm_hw_write (sw, buf, len);
sdl_unlock_and_post (s);
return ret;
}
static int AUD_to_sdlfmt (audfmt_e fmt, int *shift)
{
*shift = 0;
switch (fmt) {
case AUD_FMT_S8: return AUDIO_S8;
case AUD_FMT_U8: return AUDIO_U8;
case AUD_FMT_S16: *shift = 1; return AUDIO_S16LSB;
case AUD_FMT_U16: *shift = 1; return AUDIO_U16LSB;
default:
dolog ("Internal logic error: Bad audio format %d\nAborting\n", fmt);
exit (EXIT_FAILURE);
}
}
static int sdl_to_audfmt (int fmt)
{
switch (fmt) {
case AUDIO_S8: return AUD_FMT_S8;
case AUDIO_U8: return AUD_FMT_U8;
case AUDIO_S16LSB: return AUD_FMT_S16;
case AUDIO_U16LSB: return AUD_FMT_U16;
default:
dolog ("Internal logic error: Unrecognized SDL audio format %d\n"
"Aborting\n", fmt);
exit (EXIT_FAILURE);
}
}
static int sdl_open (SDL_AudioSpec *req, SDL_AudioSpec *obt)
{
int status;
status = SDL_OpenAudio (req, obt);
if (status) {
dolog ("SDL_OpenAudio failed\nReason: %s\n", errstr ());
}
return status;
}
static void sdl_close (SDLAudioState *s)
{
if (s->initialized) {
sdl_lock (s);
s->exit = 1;
sdl_unlock_and_post (s);
SDL_PauseAudio (1);
SDL_CloseAudio ();
s->initialized = 0;
}
}
static void sdl_callback (void *opaque, Uint8 *buf, int len)
{
SDLVoice *sdl = opaque;
SDLAudioState *s = &glob_sdl;
HWVoice *hw = &sdl->hw;
int samples = len >> hw->shift;
if (s->exit) {
return;
}
while (samples) {
int to_mix, live, decr;
/* dolog ("in callback samples=%d\n", samples); */
sdl_wait (s);
if (s->exit) {
return;
}
sdl_lock (s);
live = pcm_hw_get_live (hw);
if (live <= 0)
goto again;
/* dolog ("in callback live=%d\n", live); */
to_mix = audio_MIN (samples, live);
decr = to_mix;
while (to_mix) {
int chunk = audio_MIN (to_mix, hw->samples - hw->rpos);
st_sample_t *src = hw->mix_buf + hw->rpos;
/* dolog ("in callback to_mix %d, chunk %d\n", to_mix, chunk); */
hw->clip (buf, src, chunk);
memset (src, 0, chunk * sizeof (st_sample_t));
hw->rpos = (hw->rpos + chunk) % hw->samples;
to_mix -= chunk;
buf += chunk << hw->shift;
}
samples -= decr;
pcm_hw_dec_live (hw, decr);
again:
sdl_unlock (s);
}
/* dolog ("done len=%d\n", len); */
}
static void sdl_hw_fini (HWVoice *hw)
{
ldebug ("sdl_hw_fini %d fixed=%d\n",
glob_sdl.initialized, audio_conf.fixed_format);
sdl_close (&glob_sdl);
}
static int sdl_hw_init (HWVoice *hw, int freq, int nchannels, audfmt_e fmt)
{
SDLVoice *sdl = (SDLVoice *) hw;
SDLAudioState *s = &glob_sdl;
SDL_AudioSpec req, obt;
int shift;
ldebug ("sdl_hw_init %d freq=%d fixed=%d\n",
s->initialized, freq, audio_conf.fixed_format);
if (nchannels != 2) {
dolog ("Bogus channel count %d\n", nchannels);
return -1;
}
req.freq = freq;
req.format = AUD_to_sdlfmt (fmt, &shift);
req.channels = nchannels;
req.samples = conf.nb_samples;
shift <<= nchannels == 2;
req.callback = sdl_callback;
req.userdata = sdl;
if (sdl_open (&req, &obt))
return -1;
hw->freq = obt.freq;
hw->fmt = sdl_to_audfmt (obt.format);
hw->nchannels = obt.channels;
hw->bufsize = obt.samples << shift;
s->initialized = 1;
s->exit = 0;
SDL_PauseAudio (0);
return 0;
}
static int sdl_hw_ctl (HWVoice *hw, int cmd, ...)
{
(void) hw;
switch (cmd) {
case VOICE_ENABLE:
SDL_PauseAudio (0);
break;
case VOICE_DISABLE:
SDL_PauseAudio (1);
break;
}
return 0;
}
static void *sdl_audio_init (void)
{
SDLAudioState *s = &glob_sdl;
conf.nb_samples = audio_get_conf_int (QC_SDL_SAMPLES, conf.nb_samples);
if (SDL_InitSubSystem (SDL_INIT_AUDIO)) {
dolog ("SDL failed to initialize audio subsystem\nReason: %s\n",
errstr ());
return NULL;
}
s->mutex = SDL_CreateMutex ();
if (!s->mutex) {
dolog ("Failed to create SDL mutex\nReason: %s\n", errstr ());
SDL_QuitSubSystem (SDL_INIT_AUDIO);
return NULL;
}
s->sem = SDL_CreateSemaphore (0);
if (!s->sem) {
dolog ("Failed to create SDL semaphore\nReason: %s\n", errstr ());
SDL_DestroyMutex (s->mutex);
SDL_QuitSubSystem (SDL_INIT_AUDIO);
return NULL;
}
return s;
}
static void sdl_audio_fini (void *opaque)
{
SDLAudioState *s = opaque;
sdl_close (s);
SDL_DestroySemaphore (s->sem);
SDL_DestroyMutex (s->mutex);
SDL_QuitSubSystem (SDL_INIT_AUDIO);
}
struct pcm_ops sdl_pcm_ops = {
sdl_hw_init,
sdl_hw_fini,
sdl_hw_run,
sdl_hw_write,
sdl_hw_ctl
};
struct audio_output_driver sdl_output_driver = {
"sdl",
sdl_audio_init,
sdl_audio_fini,
&sdl_pcm_ops,
1,
1,
sizeof (SDLVoice)
};