audio/sdlaudio.c

   1 /*
   2  * QEMU SDL audio driver
   3  *
   4  * Copyright (c) 2004-2005 Vassili Karpov (malc)
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24 #include <SDL.h>
  25 #include <SDL_thread.h>
  26 #include "qemu-common.h"
  27 #include "audio.h"
  28
  29 #ifndef _WIN32
  30 #ifdef __sun__
  31 #define _POSIX_PTHREAD_SEMANTICS 1
  32 #elif defined(__OpenBSD__) || defined(__FreeBSD__) || defined(__DragonFly__)
  33 #include <pthread.h>
  34 #endif
  35 #include <signal.h>
  36 #endif
  37
  38 #define AUDIO_CAP "sdl"
  39 #include "audio_int.h"
  40
  41 typedef struct SDLVoiceOut {
  42     HWVoiceOut hw;
  43     int live;
  44     int decr;
  45     int pending;
  46 } SDLVoiceOut;
  47
  48 static struct {
  49     int nb_samples;
  50 } conf = {
  51     .nb_samples = 1024
  52 };
  53
  54 static struct SDLAudioState {
  55     int exit;
  56     SDL_mutex *mutex;
  57     SDL_sem *sem;
  58     int initialized;
  59 } glob_sdl;
  60 typedef struct SDLAudioState SDLAudioState;
  61
  62 static void GCC_FMT_ATTR (1, 2) sdl_logerr (const char *fmt, ...)
  63 {
  64     va_list ap;
  65
  66     va_start (ap, fmt);
  67     AUD_vlog (AUDIO_CAP, fmt, ap);
  68     va_end (ap);
  69
  70     AUD_log (AUDIO_CAP, "Reason: %s\n", SDL_GetError ());
  71 }
  72
  73 static int sdl_lock (SDLAudioState *s, const char *forfn)
  74 {
  75     if (SDL_LockMutex (s->mutex)) {
  76         sdl_logerr ("SDL_LockMutex for %s failed\n", forfn);
  77         return -1;
  78     }
  79     return 0;
  80 }
  81
  82 static int sdl_unlock (SDLAudioState *s, const char *forfn)
  83 {
  84     if (SDL_UnlockMutex (s->mutex)) {
  85         sdl_logerr ("SDL_UnlockMutex for %s failed\n", forfn);
  86         return -1;
  87     }
  88     return 0;
  89 }
  90
  91 static int sdl_post (SDLAudioState *s, const char *forfn)
  92 {
  93     if (SDL_SemPost (s->sem)) {
  94         sdl_logerr ("SDL_SemPost for %s failed\n", forfn);
  95         return -1;
  96     }
  97     return 0;
  98 }
  99
 100 static int sdl_wait (SDLAudioState *s, const char *forfn)
 101 {
 102     if (SDL_SemWait (s->sem)) {
 103         sdl_logerr ("SDL_SemWait for %s failed\n", forfn);
 104         return -1;
 105     }
 106     return 0;
 107 }
 108
 109 static int sdl_unlock_and_post (SDLAudioState *s, const char *forfn)
 110 {
 111     if (sdl_unlock (s, forfn)) {
 112         return -1;
 113     }
 114
 115     return sdl_post (s, forfn);
 116 }
 117
 118 static int aud_to_sdlfmt (audfmt_e fmt, int *shift)
 119 {
 120     switch (fmt) {
 121     case AUD_FMT_S8:
 122         *shift = 0;
 123         return AUDIO_S8;
 124
 125     case AUD_FMT_U8:
 126         *shift = 0;
 127         return AUDIO_U8;
 128
 129     case AUD_FMT_S16:
 130         *shift = 1;
 131         return AUDIO_S16LSB;
 132
 133     case AUD_FMT_U16:
 134         *shift = 1;
 135         return AUDIO_U16LSB;
 136
 137     default:
 138         dolog ("Internal logic error: Bad audio format %d\n", fmt);
 139 #ifdef DEBUG_AUDIO
 140         abort ();
 141 #endif
 142         return AUDIO_U8;
 143     }
 144 }
 145
 146 static int sdl_to_audfmt (int sdlfmt, audfmt_e *fmt, int *endianess)
 147 {
 148     switch (sdlfmt) {
 149     case AUDIO_S8:
 150         *endianess = 0;
 151         *fmt = AUD_FMT_S8;
 152         break;
 153
 154     case AUDIO_U8:
 155         *endianess = 0;
 156         *fmt = AUD_FMT_U8;
 157         break;
 158
 159     case AUDIO_S16LSB:
 160         *endianess = 0;
 161         *fmt = AUD_FMT_S16;
 162         break;
 163
 164     case AUDIO_U16LSB:
 165         *endianess = 0;
 166         *fmt = AUD_FMT_U16;
 167         break;
 168
 169     case AUDIO_S16MSB:
 170         *endianess = 1;
 171         *fmt = AUD_FMT_S16;
 172         break;
 173
 174     case AUDIO_U16MSB:
 175         *endianess = 1;
 176         *fmt = AUD_FMT_U16;
 177         break;
 178
 179     default:
 180         dolog ("Unrecognized SDL audio format %d\n", sdlfmt);
 181         return -1;
 182     }
 183
 184     return 0;
 185 }
 186
 187 static int sdl_open (SDL_AudioSpec *req, SDL_AudioSpec *obt)
 188 {
 189     int status;
 190 #ifndef _WIN32
 191     sigset_t new, old;
 192
 193     /* Make sure potential threads created by SDL don't hog signals.  */
 194     sigfillset (&new);
 195     pthread_sigmask (SIG_BLOCK, &new, &old);
 196 #endif
 197
 198     status = SDL_OpenAudio (req, obt);
 199     if (status) {
 200         sdl_logerr ("SDL_OpenAudio failed\n");
 201     }
 202
 203 #ifndef _WIN32
 204     pthread_sigmask (SIG_SETMASK, &old, NULL);
 205 #endif
 206     return status;
 207 }
 208
 209 static void sdl_close (SDLAudioState *s)
 210 {
 211     if (s->initialized) {
 212         sdl_lock (s, "sdl_close");
 213         s->exit = 1;
 214         sdl_unlock_and_post (s, "sdl_close");
 215         SDL_PauseAudio (1);
 216         SDL_CloseAudio ();
 217         s->initialized = 0;
 218     }
 219 }
 220
 221 static void sdl_callback (void *opaque, Uint8 *buf, int len)
 222 {
 223     SDLVoiceOut *sdl = opaque;
 224     SDLAudioState *s = &glob_sdl;
 225     HWVoiceOut *hw = &sdl->hw;
 226     int samples = len >> hw->info.shift;
 227
 228     if (sdl_lock (s, "sdl_callback")) {
 229         return;
 230     }
 231
 232     if (s->exit) {
 233         return;
 234     }
 235
 236     while (samples) {
 237         int to_mix, decr;
 238
 239         while (!sdl->pending) {
 240             if (sdl_unlock (s, "sdl_callback")) {
 241                 return;
 242             }
 243
 244             sdl_wait (s, "sdl_callback");
 245             if (s->exit) {
 246                 return;
 247             }
 248
 249             if (sdl_lock (s, "sdl_callback")) {
 250                 return;
 251             }
 252             sdl->pending += sdl->live;
 253             sdl->live = 0;
 254         }
 255
 256         to_mix = audio_MIN (samples, sdl->pending);
 257         decr = audio_pcm_hw_clip_out (hw, buf, to_mix, 0);
 258         buf += decr << hw->info.shift;
 259         samples -= decr;
 260         sdl->decr += decr;
 261         sdl->pending -= decr;
 262     }
 263
 264     if (sdl_unlock (s, "sdl_callback")) {
 265         return;
 266     }
 267 }
 268
 269 static int sdl_write_out (SWVoiceOut *sw, void *buf, int len)
 270 {
 271     return audio_pcm_sw_write (sw, buf, len);
 272 }
 273
 274 static int sdl_run_out (HWVoiceOut *hw, int live)
 275 {
 276     int decr;
 277     SDLVoiceOut *sdl = (SDLVoiceOut *) hw;
 278     SDLAudioState *s = &glob_sdl;
 279
 280     if (sdl_lock (s, "sdl_run_out")) {
 281         return 0;
 282     }
 283
 284     sdl->live = live;
 285     decr = sdl->decr;
 286     sdl->decr = 0;
 287
 288     if (sdl->live > 0) {
 289         sdl_unlock_and_post (s, "sdl_run_out");
 290     }
 291     else {
 292         sdl_unlock (s, "sdl_run_out");
 293     }
 294     return decr;
 295 }
 296
 297 static void sdl_fini_out (HWVoiceOut *hw)
 298 {
 299     (void) hw;
 300
 301     sdl_close (&glob_sdl);
 302 }
 303
 304 static int sdl_init_out (HWVoiceOut *hw, struct audsettings *as)
 305 {
 306     SDLVoiceOut *sdl = (SDLVoiceOut *) hw;
 307     SDLAudioState *s = &glob_sdl;
 308     SDL_AudioSpec req, obt;
 309     int shift;
 310     int endianess;
 311     int err;
 312     audfmt_e effective_fmt;
 313     struct audsettings obt_as;
 314
 315     shift <<= as->nchannels == 2;
 316
 317     req.freq = as->freq;
 318     req.format = aud_to_sdlfmt (as->fmt, &shift);
 319     req.channels = as->nchannels;
 320     req.samples = conf.nb_samples;
 321     req.callback = sdl_callback;
 322     req.userdata = sdl;
 323
 324     if (sdl_open (&req, &obt)) {
 325         return -1;
 326     }
 327
 328     err = sdl_to_audfmt (obt.format, &effective_fmt, &endianess);
 329     if (err) {
 330         sdl_close (s);
 331         return -1;
 332     }
 333
 334     obt_as.freq = obt.freq;
 335     obt_as.nchannels = obt.channels;
 336     obt_as.fmt = effective_fmt;
 337     obt_as.endianness = endianess;
 338
 339     audio_pcm_init_info (&hw->info, &obt_as);
 340     hw->samples = obt.samples;
 341
 342     s->initialized = 1;
 343     s->exit = 0;
 344     SDL_PauseAudio (0);
 345     return 0;
 346 }
 347
 348 static int sdl_ctl_out (HWVoiceOut *hw, int cmd, ...)
 349 {
 350     (void) hw;
 351
 352     switch (cmd) {
 353     case VOICE_ENABLE:
 354         SDL_PauseAudio (0);
 355         break;
 356
 357     case VOICE_DISABLE:
 358         SDL_PauseAudio (1);
 359         break;
 360     }
 361     return 0;
 362 }
 363
 364 static void *sdl_audio_init (void)
 365 {
 366     SDLAudioState *s = &glob_sdl;
 367
 368     if (SDL_InitSubSystem (SDL_INIT_AUDIO)) {
 369         sdl_logerr ("SDL failed to initialize audio subsystem\n");
 370         return NULL;
 371     }
 372
 373     s->mutex = SDL_CreateMutex ();
 374     if (!s->mutex) {
 375         sdl_logerr ("Failed to create SDL mutex\n");
 376         SDL_QuitSubSystem (SDL_INIT_AUDIO);
 377         return NULL;
 378     }
 379
 380     s->sem = SDL_CreateSemaphore (0);
 381     if (!s->sem) {
 382         sdl_logerr ("Failed to create SDL semaphore\n");
 383         SDL_DestroyMutex (s->mutex);
 384         SDL_QuitSubSystem (SDL_INIT_AUDIO);
 385         return NULL;
 386     }
 387
 388     return s;
 389 }
 390
 391 static void sdl_audio_fini (void *opaque)
 392 {
 393     SDLAudioState *s = opaque;
 394     sdl_close (s);
 395     SDL_DestroySemaphore (s->sem);
 396     SDL_DestroyMutex (s->mutex);
 397     SDL_QuitSubSystem (SDL_INIT_AUDIO);
 398 }
 399
 400 static struct audio_option sdl_options[] = {
 401     {
 402         .name  = "SAMPLES",
 403         .tag   = AUD_OPT_INT,
 404         .valp  = &conf.nb_samples,
 405         .descr = "Size of SDL buffer in samples"
 406     },
 407     { /* End of list */ }
 408 };
 409
 410 static struct audio_pcm_ops sdl_pcm_ops = {
 411     .init_out = sdl_init_out,
 412     .fini_out = sdl_fini_out,
 413     .run_out  = sdl_run_out,
 414     .write    = sdl_write_out,
 415     .ctl_out  = sdl_ctl_out,
 416 };
 417
 418 struct audio_driver sdl_audio_driver = {
 419     .name           = "sdl",
 420     .descr          = "SDL http://www.libsdl.org",
 421     .options        = sdl_options,
 422     .init           = sdl_audio_init,
 423     .fini           = sdl_audio_fini,
 424     .pcm_ops        = &sdl_pcm_ops,
 425     .can_be_default = 1,
 426     .max_voices_out = 1,
 427     .max_voices_in  = 0,
 428     .voice_size_out = sizeof (SDLVoiceOut),
 429     .voice_size_in  = 0
 430 };