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 "vl.h"
  27
  28 #ifndef _WIN32
  29 #ifdef __sun__
  30 #define _POSIX_PTHREAD_SEMANTICS 1
  31 #endif
  32 #include <signal.h>
  33 #endif
  34
  35 #define AUDIO_CAP "sdl"
  36 #include "audio_int.h"
  37
  38 typedef struct SDLVoiceOut {
  39     HWVoiceOut hw;
  40     int live;
  41     int rpos;
  42     int decr;
  43 } SDLVoiceOut;
  44
  45 static struct {
  46     int nb_samples;
  47 } conf = {
  48     1024
  49 };
  50
  51 struct SDLAudioState {
  52     int exit;
  53     SDL_mutex *mutex;
  54     SDL_sem *sem;
  55     int initialized;
  56 } glob_sdl;
  57 typedef struct SDLAudioState SDLAudioState;
  58
  59 static void GCC_FMT_ATTR (1, 2) sdl_logerr (const char *fmt, ...)
  60 {
  61     va_list ap;
  62
  63     va_start (ap, fmt);
  64     AUD_vlog (AUDIO_CAP, fmt, ap);
  65     va_end (ap);
  66
  67     AUD_log (AUDIO_CAP, "Reason: %s\n", SDL_GetError ());
  68 }
  69
  70 static int sdl_lock (SDLAudioState *s, const char *forfn)
  71 {
  72     if (SDL_LockMutex (s->mutex)) {
  73         sdl_logerr ("SDL_LockMutex for %s failed\n", forfn);
  74         return -1;
  75     }
  76     return 0;
  77 }
  78
  79 static int sdl_unlock (SDLAudioState *s, const char *forfn)
  80 {
  81     if (SDL_UnlockMutex (s->mutex)) {
  82         sdl_logerr ("SDL_UnlockMutex for %s failed\n", forfn);
  83         return -1;
  84     }
  85     return 0;
  86 }
  87
  88 static int sdl_post (SDLAudioState *s, const char *forfn)
  89 {
  90     if (SDL_SemPost (s->sem)) {
  91         sdl_logerr ("SDL_SemPost for %s failed\n", forfn);
  92         return -1;
  93     }
  94     return 0;
  95 }
  96
  97 static int sdl_wait (SDLAudioState *s, const char *forfn)
  98 {
  99     if (SDL_SemWait (s->sem)) {
 100         sdl_logerr ("SDL_SemWait for %s failed\n", forfn);
 101         return -1;
 102     }
 103     return 0;
 104 }
 105
 106 static int sdl_unlock_and_post (SDLAudioState *s, const char *forfn)
 107 {
 108     if (sdl_unlock (s, forfn)) {
 109         return -1;
 110     }
 111
 112     return sdl_post (s, forfn);
 113 }
 114
 115 static int aud_to_sdlfmt (audfmt_e fmt, int *shift)
 116 {
 117     switch (fmt) {
 118     case AUD_FMT_S8:
 119         *shift = 0;
 120         return AUDIO_S8;
 121
 122     case AUD_FMT_U8:
 123         *shift = 0;
 124         return AUDIO_U8;
 125
 126     case AUD_FMT_S16:
 127         *shift = 1;
 128         return AUDIO_S16LSB;
 129
 130     case AUD_FMT_U16:
 131         *shift = 1;
 132         return AUDIO_U16LSB;
 133
 134     default:
 135         dolog ("Internal logic error: Bad audio format %d\n", fmt);
 136 #ifdef DEBUG_AUDIO
 137         abort ();
 138 #endif
 139         return AUDIO_U8;
 140     }
 141 }
 142
 143 static int sdl_to_audfmt (int sdlfmt, audfmt_e *fmt, int *endianess)
 144 {
 145     switch (sdlfmt) {
 146     case AUDIO_S8:
 147         *endianess = 0;
 148         *fmt = AUD_FMT_S8;
 149         break;
 150
 151     case AUDIO_U8:
 152         *endianess = 0;
 153         *fmt = AUD_FMT_U8;
 154         break;
 155
 156     case AUDIO_S16LSB:
 157         *endianess = 0;
 158         *fmt = AUD_FMT_S16;
 159         break;
 160
 161     case AUDIO_U16LSB:
 162         *endianess = 0;
 163         *fmt = AUD_FMT_U16;
 164         break;
 165
 166     case AUDIO_S16MSB:
 167         *endianess = 1;
 168         *fmt = AUD_FMT_S16;
 169         break;
 170
 171     case AUDIO_U16MSB:
 172         *endianess = 1;
 173         *fmt = AUD_FMT_U16;
 174         break;
 175
 176     default:
 177         dolog ("Unrecognized SDL audio format %d\n", sdlfmt);
 178         return -1;
 179     }
 180
 181     return 0;
 182 }
 183
 184 static int sdl_open (SDL_AudioSpec *req, SDL_AudioSpec *obt)
 185 {
 186     int status;
 187 #ifndef _WIN32
 188     sigset_t new, old;
 189
 190     /* Make sure potential threads created by SDL don't hog signals.  */
 191     sigfillset (&new);
 192     pthread_sigmask (SIG_BLOCK, &new, &old);
 193 #endif
 194
 195     status = SDL_OpenAudio (req, obt);
 196     if (status) {
 197         sdl_logerr ("SDL_OpenAudio failed\n");
 198     }
 199
 200 #ifndef _WIN32
 201     pthread_sigmask (SIG_SETMASK, &old, 0);
 202 #endif
 203     return status;
 204 }
 205
 206 static void sdl_close (SDLAudioState *s)
 207 {
 208     if (s->initialized) {
 209         sdl_lock (s, "sdl_close");
 210         s->exit = 1;
 211         sdl_unlock_and_post (s, "sdl_close");
 212         SDL_PauseAudio (1);
 213         SDL_CloseAudio ();
 214         s->initialized = 0;
 215     }
 216 }
 217
 218 static void sdl_callback (void *opaque, Uint8 *buf, int len)
 219 {
 220     SDLVoiceOut *sdl = opaque;
 221     SDLAudioState *s = &glob_sdl;
 222     HWVoiceOut *hw = &sdl->hw;
 223     int samples = len >> hw->info.shift;
 224
 225     if (s->exit) {
 226         return;
 227     }
 228
 229     while (samples) {
 230         int to_mix, decr;
 231
 232         /* dolog ("in callback samples=%d\n", samples); */
 233         sdl_wait (s, "sdl_callback");
 234         if (s->exit) {
 235             return;
 236         }
 237
 238         if (sdl_lock (s, "sdl_callback")) {
 239             return;
 240         }
 241
 242         if (audio_bug (AUDIO_FUNC, sdl->live < 0 || sdl->live > hw->samples)) {
 243             dolog ("sdl->live=%d hw->samples=%d\n",
 244                    sdl->live, hw->samples);
 245             return;
 246         }
 247
 248         if (!sdl->live) {
 249             goto again;
 250         }
 251
 252         /* dolog ("in callback live=%d\n", live); */
 253         to_mix = audio_MIN (samples, sdl->live);
 254         decr = to_mix;
 255         while (to_mix) {
 256             int chunk = audio_MIN (to_mix, hw->samples - hw->rpos);
 257             st_sample_t *src = hw->mix_buf + hw->rpos;
 258
 259             /* dolog ("in callback to_mix %d, chunk %d\n", to_mix, chunk); */
 260             hw->clip (buf, src, chunk);
 261             sdl->rpos = (sdl->rpos + chunk) % hw->samples;
 262             to_mix -= chunk;
 263             buf += chunk << hw->info.shift;
 264         }
 265         samples -= decr;
 266         sdl->live -= decr;
 267         sdl->decr += decr;
 268
 269     again:
 270         if (sdl_unlock (s, "sdl_callback")) {
 271             return;
 272         }
 273     }
 274     /* dolog ("done len=%d\n", len); */
 275 }
 276
 277 static int sdl_write_out (SWVoiceOut *sw, void *buf, int len)
 278 {
 279     return audio_pcm_sw_write (sw, buf, len);
 280 }
 281
 282 static int sdl_run_out (HWVoiceOut *hw)
 283 {
 284     int decr, live;
 285     SDLVoiceOut *sdl = (SDLVoiceOut *) hw;
 286     SDLAudioState *s = &glob_sdl;
 287
 288     if (sdl_lock (s, "sdl_callback")) {
 289         return 0;
 290     }
 291
 292     live = audio_pcm_hw_get_live_out (hw);
 293
 294     if (sdl->decr > live) {
 295         ldebug ("sdl->decr %d live %d sdl->live %d\n",
 296                 sdl->decr,
 297                 live,
 298                 sdl->live);
 299     }
 300
 301     decr = audio_MIN (sdl->decr, live);
 302     sdl->decr -= decr;
 303
 304     sdl->live = live - decr;
 305     hw->rpos = sdl->rpos;
 306
 307     if (sdl->live > 0) {
 308         sdl_unlock_and_post (s, "sdl_callback");
 309     }
 310     else {
 311         sdl_unlock (s, "sdl_callback");
 312     }
 313     return decr;
 314 }
 315
 316 static void sdl_fini_out (HWVoiceOut *hw)
 317 {
 318     (void) hw;
 319
 320     sdl_close (&glob_sdl);
 321 }
 322
 323 static int sdl_init_out (HWVoiceOut *hw, audsettings_t *as)
 324 {
 325     SDLVoiceOut *sdl = (SDLVoiceOut *) hw;
 326     SDLAudioState *s = &glob_sdl;
 327     SDL_AudioSpec req, obt;
 328     int shift;
 329     int endianess;
 330     int err;
 331     audfmt_e effective_fmt;
 332     audsettings_t obt_as;
 333
 334     shift <<= as->nchannels == 2;
 335
 336     req.freq = as->freq;
 337     req.format = aud_to_sdlfmt (as->fmt, &shift);
 338     req.channels = as->nchannels;
 339     req.samples = conf.nb_samples;
 340     req.callback = sdl_callback;
 341     req.userdata = sdl;
 342
 343     if (sdl_open (&req, &obt)) {
 344         return -1;
 345     }
 346
 347     err = sdl_to_audfmt (obt.format, &effective_fmt, &endianess);
 348     if (err) {
 349         sdl_close (s);
 350         return -1;
 351     }
 352
 353     obt_as.freq = obt.freq;
 354     obt_as.nchannels = obt.channels;
 355     obt_as.fmt = effective_fmt;
 356     obt_as.endianness = endianess;
 357
 358     audio_pcm_init_info (&hw->info, &obt_as);
 359     hw->samples = obt.samples;
 360
 361     s->initialized = 1;
 362     s->exit = 0;
 363     SDL_PauseAudio (0);
 364     return 0;
 365 }
 366
 367 static int sdl_ctl_out (HWVoiceOut *hw, int cmd, ...)
 368 {
 369     (void) hw;
 370
 371     switch (cmd) {
 372     case VOICE_ENABLE:
 373         SDL_PauseAudio (0);
 374         break;
 375
 376     case VOICE_DISABLE:
 377         SDL_PauseAudio (1);
 378         break;
 379     }
 380     return 0;
 381 }
 382
 383 static void *sdl_audio_init (void)
 384 {
 385     SDLAudioState *s = &glob_sdl;
 386
 387     if (SDL_InitSubSystem (SDL_INIT_AUDIO)) {
 388         sdl_logerr ("SDL failed to initialize audio subsystem\n");
 389         return NULL;
 390     }
 391
 392     s->mutex = SDL_CreateMutex ();
 393     if (!s->mutex) {
 394         sdl_logerr ("Failed to create SDL mutex\n");
 395         SDL_QuitSubSystem (SDL_INIT_AUDIO);
 396         return NULL;
 397     }
 398
 399     s->sem = SDL_CreateSemaphore (0);
 400     if (!s->sem) {
 401         sdl_logerr ("Failed to create SDL semaphore\n");
 402         SDL_DestroyMutex (s->mutex);
 403         SDL_QuitSubSystem (SDL_INIT_AUDIO);
 404         return NULL;
 405     }
 406
 407     return s;
 408 }
 409
 410 static void sdl_audio_fini (void *opaque)
 411 {
 412     SDLAudioState *s = opaque;
 413     sdl_close (s);
 414     SDL_DestroySemaphore (s->sem);
 415     SDL_DestroyMutex (s->mutex);
 416     SDL_QuitSubSystem (SDL_INIT_AUDIO);
 417 }
 418
 419 static struct audio_option sdl_options[] = {
 420     {"SAMPLES", AUD_OPT_INT, &conf.nb_samples,
 421      "Size of SDL buffer in samples", NULL, 0},
 422     {NULL, 0, NULL, NULL, NULL, 0}
 423 };
 424
 425 static struct audio_pcm_ops sdl_pcm_ops = {
 426     sdl_init_out,
 427     sdl_fini_out,
 428     sdl_run_out,
 429     sdl_write_out,
 430     sdl_ctl_out,
 431
 432     NULL,
 433     NULL,
 434     NULL,
 435     NULL,
 436     NULL
 437 };
 438
 439 struct audio_driver sdl_audio_driver = {
 440     INIT_FIELD (name           = ) "sdl",
 441     INIT_FIELD (descr          = ) "SDL http://www.libsdl.org",
 442     INIT_FIELD (options        = ) sdl_options,
 443     INIT_FIELD (init           = ) sdl_audio_init,
 444     INIT_FIELD (fini           = ) sdl_audio_fini,
 445     INIT_FIELD (pcm_ops        = ) &sdl_pcm_ops,
 446     INIT_FIELD (can_be_default = ) 1,
 447     INIT_FIELD (max_voices_out = ) 1,
 448     INIT_FIELD (max_voices_in  = ) 0,
 449     INIT_FIELD (voice_size_out = ) sizeof (SDLVoiceOut),
 450     INIT_FIELD (voice_size_in  = ) 0
 451 };