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