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__)
  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 rpos;
  45     int decr;
  46 } SDLVoiceOut;
  47
  48 static struct {
  49     int nb_samples;
  50 } conf = {
  51     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, 0);
 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 (s->exit) {
 229         return;
 230     }
 231
 232     while (samples) {
 233         int to_mix, decr;
 234
 235         /* dolog ("in callback samples=%d\n", samples); */
 236         sdl_wait (s, "sdl_callback");
 237         if (s->exit) {
 238             return;
 239         }
 240
 241         if (sdl_lock (s, "sdl_callback")) {
 242             return;
 243         }
 244
 245         if (audio_bug (AUDIO_FUNC, sdl->live < 0 || sdl->live > hw->samples)) {
 246             dolog ("sdl->live=%d hw->samples=%d\n",
 247                    sdl->live, hw->samples);
 248             return;
 249         }
 250
 251         if (!sdl->live) {
 252             goto again;
 253         }
 254
 255         /* dolog ("in callback live=%d\n", live); */
 256         to_mix = audio_MIN (samples, sdl->live);
 257         decr = to_mix;
 258         while (to_mix) {
 259             int chunk = audio_MIN (to_mix, hw->samples - hw->rpos);
 260             struct st_sample *src = hw->mix_buf + hw->rpos;
 261
 262             /* dolog ("in callback to_mix %d, chunk %d\n", to_mix, chunk); */
 263             hw->clip (buf, src, chunk);
 264             sdl->rpos = (sdl->rpos + chunk) % hw->samples;
 265             to_mix -= chunk;
 266             buf += chunk << hw->info.shift;
 267         }
 268         samples -= decr;
 269         sdl->live -= decr;
 270         sdl->decr += decr;
 271
 272     again:
 273         if (sdl_unlock (s, "sdl_callback")) {
 274             return;
 275         }
 276     }
 277     /* dolog ("done len=%d\n", len); */
 278 }
 279
 280 static int sdl_write_out (SWVoiceOut *sw, void *buf, int len)
 281 {
 282     return audio_pcm_sw_write (sw, buf, len);
 283 }
 284
 285 static int sdl_run_out (HWVoiceOut *hw)
 286 {
 287     int decr, live;
 288     SDLVoiceOut *sdl = (SDLVoiceOut *) hw;
 289     SDLAudioState *s = &glob_sdl;
 290
 291     if (sdl_lock (s, "sdl_callback")) {
 292         return 0;
 293     }
 294
 295     live = audio_pcm_hw_get_live_out (hw);
 296
 297     if (sdl->decr > live) {
 298         ldebug ("sdl->decr %d live %d sdl->live %d\n",
 299                 sdl->decr,
 300                 live,
 301                 sdl->live);
 302     }
 303
 304     decr = audio_MIN (sdl->decr, live);
 305     sdl->decr -= decr;
 306
 307     sdl->live = live - decr;
 308     hw->rpos = sdl->rpos;
 309
 310     if (sdl->live > 0) {
 311         sdl_unlock_and_post (s, "sdl_callback");
 312     }
 313     else {
 314         sdl_unlock (s, "sdl_callback");
 315     }
 316     return decr;
 317 }
 318
 319 static void sdl_fini_out (HWVoiceOut *hw)
 320 {
 321     (void) hw;
 322
 323     sdl_close (&glob_sdl);
 324 }
 325
 326 static int sdl_init_out (HWVoiceOut *hw, struct audsettings *as)
 327 {
 328     SDLVoiceOut *sdl = (SDLVoiceOut *) hw;
 329     SDLAudioState *s = &glob_sdl;
 330     SDL_AudioSpec req, obt;
 331     int shift;
 332     int endianess;
 333     int err;
 334     audfmt_e effective_fmt;
 335     struct audsettings obt_as;
 336
 337     shift <<= as->nchannels == 2;
 338
 339     req.freq = as->freq;
 340     req.format = aud_to_sdlfmt (as->fmt, &shift);
 341     req.channels = as->nchannels;
 342     req.samples = conf.nb_samples;
 343     req.callback = sdl_callback;
 344     req.userdata = sdl;
 345
 346     if (sdl_open (&req, &obt)) {
 347         return -1;
 348     }
 349
 350     err = sdl_to_audfmt (obt.format, &effective_fmt, &endianess);
 351     if (err) {
 352         sdl_close (s);
 353         return -1;
 354     }
 355
 356     obt_as.freq = obt.freq;
 357     obt_as.nchannels = obt.channels;
 358     obt_as.fmt = effective_fmt;
 359     obt_as.endianness = endianess;
 360
 361     audio_pcm_init_info (&hw->info, &obt_as);
 362     hw->samples = obt.samples;
 363
 364     s->initialized = 1;
 365     s->exit = 0;
 366     SDL_PauseAudio (0);
 367     return 0;
 368 }
 369
 370 static int sdl_ctl_out (HWVoiceOut *hw, int cmd, ...)
 371 {
 372     (void) hw;
 373
 374     switch (cmd) {
 375     case VOICE_ENABLE:
 376         SDL_PauseAudio (0);
 377         break;
 378
 379     case VOICE_DISABLE:
 380         SDL_PauseAudio (1);
 381         break;
 382     }
 383     return 0;
 384 }
 385
 386 static void *sdl_audio_init (void)
 387 {
 388     SDLAudioState *s = &glob_sdl;
 389
 390     if (SDL_InitSubSystem (SDL_INIT_AUDIO)) {
 391         sdl_logerr ("SDL failed to initialize audio subsystem\n");
 392         return NULL;
 393     }
 394
 395     s->mutex = SDL_CreateMutex ();
 396     if (!s->mutex) {
 397         sdl_logerr ("Failed to create SDL mutex\n");
 398         SDL_QuitSubSystem (SDL_INIT_AUDIO);
 399         return NULL;
 400     }
 401
 402     s->sem = SDL_CreateSemaphore (0);
 403     if (!s->sem) {
 404         sdl_logerr ("Failed to create SDL semaphore\n");
 405         SDL_DestroyMutex (s->mutex);
 406         SDL_QuitSubSystem (SDL_INIT_AUDIO);
 407         return NULL;
 408     }
 409
 410     return s;
 411 }
 412
 413 static void sdl_audio_fini (void *opaque)
 414 {
 415     SDLAudioState *s = opaque;
 416     sdl_close (s);
 417     SDL_DestroySemaphore (s->sem);
 418     SDL_DestroyMutex (s->mutex);
 419     SDL_QuitSubSystem (SDL_INIT_AUDIO);
 420 }
 421
 422 static struct audio_option sdl_options[] = {
 423     {"SAMPLES", AUD_OPT_INT, &conf.nb_samples,
 424      "Size of SDL buffer in samples", NULL, 0},
 425     {NULL, 0, NULL, NULL, NULL, 0}
 426 };
 427
 428 static struct audio_pcm_ops sdl_pcm_ops = {
 429     sdl_init_out,
 430     sdl_fini_out,
 431     sdl_run_out,
 432     sdl_write_out,
 433     sdl_ctl_out,
 434
 435     NULL,
 436     NULL,
 437     NULL,
 438     NULL,
 439     NULL
 440 };
 441
 442 struct audio_driver sdl_audio_driver = {
 443     INIT_FIELD (name           = ) "sdl",
 444     INIT_FIELD (descr          = ) "SDL http://www.libsdl.org",
 445     INIT_FIELD (options        = ) sdl_options,
 446     INIT_FIELD (init           = ) sdl_audio_init,
 447     INIT_FIELD (fini           = ) sdl_audio_fini,
 448     INIT_FIELD (pcm_ops        = ) &sdl_pcm_ops,
 449     INIT_FIELD (can_be_default = ) 1,
 450     INIT_FIELD (max_voices_out = ) 1,
 451     INIT_FIELD (max_voices_in  = ) 0,
 452     INIT_FIELD (voice_size_out = ) sizeof (SDLVoiceOut),
 453     INIT_FIELD (voice_size_in  = ) 0
 454 };