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 rpos;
  45     int decr;
  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)
 119 {
 120     switch (fmt) {
 121     case AUD_FMT_S8:
 122         return AUDIO_S8;
 123
 124     case AUD_FMT_U8:
 125         return AUDIO_U8;
 126
 127     case AUD_FMT_S16:
 128         return AUDIO_S16LSB;
 129
 130     case AUD_FMT_U16:
 131         return AUDIO_U16LSB;
 132
 133     default:
 134         dolog ("Internal logic error: Bad audio format %d\n", fmt);
 135 #ifdef DEBUG_AUDIO
 136         abort ();
 137 #endif
 138         return AUDIO_U8;
 139     }
 140 }
 141
 142 static int sdl_to_audfmt (int sdlfmt, audfmt_e *fmt, int *endianess)
 143 {
 144     switch (sdlfmt) {
 145     case AUDIO_S8:
 146         *endianess = 0;
 147         *fmt = AUD_FMT_S8;
 148         break;
 149
 150     case AUDIO_U8:
 151         *endianess = 0;
 152         *fmt = AUD_FMT_U8;
 153         break;
 154
 155     case AUDIO_S16LSB:
 156         *endianess = 0;
 157         *fmt = AUD_FMT_S16;
 158         break;
 159
 160     case AUDIO_U16LSB:
 161         *endianess = 0;
 162         *fmt = AUD_FMT_U16;
 163         break;
 164
 165     case AUDIO_S16MSB:
 166         *endianess = 1;
 167         *fmt = AUD_FMT_S16;
 168         break;
 169
 170     case AUDIO_U16MSB:
 171         *endianess = 1;
 172         *fmt = AUD_FMT_U16;
 173         break;
 174
 175     default:
 176         dolog ("Unrecognized SDL audio format %d\n", sdlfmt);
 177         return -1;
 178     }
 179
 180     return 0;
 181 }
 182
 183 static int sdl_open (SDL_AudioSpec *req, SDL_AudioSpec *obt)
 184 {
 185     int status;
 186 #ifndef _WIN32
 187     sigset_t new, old;
 188
 189     /* Make sure potential threads created by SDL don't hog signals.  */
 190     sigfillset (&new);
 191     pthread_sigmask (SIG_BLOCK, &new, &old);
 192 #endif
 193
 194     status = SDL_OpenAudio (req, obt);
 195     if (status) {
 196         sdl_logerr ("SDL_OpenAudio failed\n");
 197     }
 198
 199 #ifndef _WIN32
 200     pthread_sigmask (SIG_SETMASK, &old, NULL);
 201 #endif
 202     return status;
 203 }
 204
 205 static void sdl_close (SDLAudioState *s)
 206 {
 207     if (s->initialized) {
 208         sdl_lock (s, "sdl_close");
 209         s->exit = 1;
 210         sdl_unlock_and_post (s, "sdl_close");
 211         SDL_PauseAudio (1);
 212         SDL_CloseAudio ();
 213         s->initialized = 0;
 214     }
 215 }
 216
 217 static void sdl_callback (void *opaque, Uint8 *buf, int len)
 218 {
 219     SDLVoiceOut *sdl = opaque;
 220     SDLAudioState *s = &glob_sdl;
 221     HWVoiceOut *hw = &sdl->hw;
 222     int samples = len >> hw->info.shift;
 223
 224     if (s->exit) {
 225         return;
 226     }
 227
 228     while (samples) {
 229         int to_mix, decr;
 230
 231         /* dolog ("in callback samples=%d\n", samples); */
 232         sdl_wait (s, "sdl_callback");
 233         if (s->exit) {
 234             return;
 235         }
 236
 237         if (sdl_lock (s, "sdl_callback")) {
 238             return;
 239         }
 240
 241         if (audio_bug (AUDIO_FUNC, sdl->live < 0 || sdl->live > hw->samples)) {
 242             dolog ("sdl->live=%d hw->samples=%d\n",
 243                    sdl->live, hw->samples);
 244             return;
 245         }
 246
 247         if (!sdl->live) {
 248             goto again;
 249         }
 250
 251         /* dolog ("in callback live=%d\n", live); */
 252         to_mix = audio_MIN (samples, sdl->live);
 253         decr = to_mix;
 254         while (to_mix) {
 255             int chunk = audio_MIN (to_mix, hw->samples - hw->rpos);
 256             struct st_sample *src = hw->mix_buf + hw->rpos;
 257
 258             /* dolog ("in callback to_mix %d, chunk %d\n", to_mix, chunk); */
 259             hw->clip (buf, src, chunk);
 260             sdl->rpos = (sdl->rpos + chunk) % hw->samples;
 261             to_mix -= chunk;
 262             buf += chunk << hw->info.shift;
 263         }
 264         samples -= decr;
 265         sdl->live -= decr;
 266         sdl->decr += decr;
 267
 268     again:
 269         if (sdl_unlock (s, "sdl_callback")) {
 270             return;
 271         }
 272     }
 273     /* dolog ("done len=%d\n", len); */
 274 }
 275
 276 static int sdl_write_out (SWVoiceOut *sw, void *buf, int len)
 277 {
 278     return audio_pcm_sw_write (sw, buf, len);
 279 }
 280
 281 static int sdl_run_out (HWVoiceOut *hw, int live)
 282 {
 283     int decr;
 284     SDLVoiceOut *sdl = (SDLVoiceOut *) hw;
 285     SDLAudioState *s = &glob_sdl;
 286
 287     if (sdl_lock (s, "sdl_run_out")) {
 288         return 0;
 289     }
 290
 291     if (sdl->decr > live) {
 292         ldebug ("sdl->decr %d live %d sdl->live %d\n",
 293                 sdl->decr,
 294                 live,
 295                 sdl->live);
 296     }
 297
 298     decr = audio_MIN (sdl->decr, live);
 299     sdl->decr -= decr;
 300
 301     sdl->live = live - decr;
 302     hw->rpos = sdl->rpos;
 303
 304     if (sdl->live > 0) {
 305         sdl_unlock_and_post (s, "sdl_run_out");
 306     }
 307     else {
 308         sdl_unlock (s, "sdl_run_out");
 309     }
 310     return decr;
 311 }
 312
 313 static void sdl_fini_out (HWVoiceOut *hw)
 314 {
 315     (void) hw;
 316
 317     sdl_close (&glob_sdl);
 318 }
 319
 320 static int sdl_init_out (HWVoiceOut *hw, struct audsettings *as)
 321 {
 322     SDLVoiceOut *sdl = (SDLVoiceOut *) hw;
 323     SDLAudioState *s = &glob_sdl;
 324     SDL_AudioSpec req, obt;
 325     int endianess;
 326     int err;
 327     audfmt_e effective_fmt;
 328     struct audsettings obt_as;
 329
 330     req.freq = as->freq;
 331     req.format = aud_to_sdlfmt (as->fmt);
 332     req.channels = as->nchannels;
 333     req.samples = conf.nb_samples;
 334     req.callback = sdl_callback;
 335     req.userdata = sdl;
 336
 337     if (sdl_open (&req, &obt)) {
 338         return -1;
 339     }
 340
 341     err = sdl_to_audfmt (obt.format, &effective_fmt, &endianess);
 342     if (err) {
 343         sdl_close (s);
 344         return -1;
 345     }
 346
 347     obt_as.freq = obt.freq;
 348     obt_as.nchannels = obt.channels;
 349     obt_as.fmt = effective_fmt;
 350     obt_as.endianness = endianess;
 351
 352     audio_pcm_init_info (&hw->info, &obt_as);
 353     hw->samples = obt.samples;
 354
 355     s->initialized = 1;
 356     s->exit = 0;
 357     SDL_PauseAudio (0);
 358     return 0;
 359 }
 360
 361 static int sdl_ctl_out (HWVoiceOut *hw, int cmd, ...)
 362 {
 363     (void) hw;
 364
 365     switch (cmd) {
 366     case VOICE_ENABLE:
 367         SDL_PauseAudio (0);
 368         break;
 369
 370     case VOICE_DISABLE:
 371         SDL_PauseAudio (1);
 372         break;
 373     }
 374     return 0;
 375 }
 376
 377 static void *sdl_audio_init (void)
 378 {
 379     SDLAudioState *s = &glob_sdl;
 380
 381     if (SDL_InitSubSystem (SDL_INIT_AUDIO)) {
 382         sdl_logerr ("SDL failed to initialize audio subsystem\n");
 383         return NULL;
 384     }
 385
 386     s->mutex = SDL_CreateMutex ();
 387     if (!s->mutex) {
 388         sdl_logerr ("Failed to create SDL mutex\n");
 389         SDL_QuitSubSystem (SDL_INIT_AUDIO);
 390         return NULL;
 391     }
 392
 393     s->sem = SDL_CreateSemaphore (0);
 394     if (!s->sem) {
 395         sdl_logerr ("Failed to create SDL semaphore\n");
 396         SDL_DestroyMutex (s->mutex);
 397         SDL_QuitSubSystem (SDL_INIT_AUDIO);
 398         return NULL;
 399     }
 400
 401     return s;
 402 }
 403
 404 static void sdl_audio_fini (void *opaque)
 405 {
 406     SDLAudioState *s = opaque;
 407     sdl_close (s);
 408     SDL_DestroySemaphore (s->sem);
 409     SDL_DestroyMutex (s->mutex);
 410     SDL_QuitSubSystem (SDL_INIT_AUDIO);
 411 }
 412
 413 static struct audio_option sdl_options[] = {
 414     {
 415         .name  = "SAMPLES",
 416         .tag   = AUD_OPT_INT,
 417         .valp  = &conf.nb_samples,
 418         .descr = "Size of SDL buffer in samples"
 419     },
 420     { /* End of list */ }
 421 };
 422
 423 static struct audio_pcm_ops sdl_pcm_ops = {
 424     .init_out = sdl_init_out,
 425     .fini_out = sdl_fini_out,
 426     .run_out  = sdl_run_out,
 427     .write    = sdl_write_out,
 428     .ctl_out  = sdl_ctl_out,
 429 };
 430
 431 struct audio_driver sdl_audio_driver = {
 432     .name           = "sdl",
 433     .descr          = "SDL http://www.libsdl.org",
 434     .options        = sdl_options,
 435     .init           = sdl_audio_init,
 436     .fini           = sdl_audio_fini,
 437     .pcm_ops        = &sdl_pcm_ops,
 438     .can_be_default = 1,
 439     .max_voices_out = 1,
 440     .max_voices_in  = 0,
 441     .voice_size_out = sizeof (SDLVoiceOut),
 442     .voice_size_in  = 0
 443 };