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
  25 #include "qemu/osdep.h"
  26 #include <SDL.h>
  27 #include <SDL_thread.h>
  28 #include "qemu/module.h"
  29 #include "audio.h"
  30
  31 #ifndef _WIN32
  32 #ifdef __sun__
  33 #define _POSIX_PTHREAD_SEMANTICS 1
  34 #elif defined(__OpenBSD__) || defined(__FreeBSD__) || defined(__DragonFly__)
  35 #include <pthread.h>
  36 #endif
  37 #endif
  38
  39 #define AUDIO_CAP "sdl"
  40 #include "audio_int.h"
  41
  42 typedef struct SDLVoiceOut {
  43     HWVoiceOut hw;
  44 } SDLVoiceOut;
  45
  46 static struct SDLAudioState {
  47     int exit;
  48     int initialized;
  49     bool driver_created;
  50     Audiodev *dev;
  51 } glob_sdl;
  52 typedef struct SDLAudioState SDLAudioState;
  53
  54 static void GCC_FMT_ATTR (1, 2) sdl_logerr (const char *fmt, ...)
  55 {
  56     va_list ap;
  57
  58     va_start (ap, fmt);
  59     AUD_vlog (AUDIO_CAP, fmt, ap);
  60     va_end (ap);
  61
  62     AUD_log (AUDIO_CAP, "Reason: %s\n", SDL_GetError ());
  63 }
  64
  65 static int aud_to_sdlfmt (AudioFormat fmt)
  66 {
  67     switch (fmt) {
  68     case AUDIO_FORMAT_S8:
  69         return AUDIO_S8;
  70
  71     case AUDIO_FORMAT_U8:
  72         return AUDIO_U8;
  73
  74     case AUDIO_FORMAT_S16:
  75         return AUDIO_S16LSB;
  76
  77     case AUDIO_FORMAT_U16:
  78         return AUDIO_U16LSB;
  79
  80     case AUDIO_FORMAT_S32:
  81         return AUDIO_S32LSB;
  82
  83     /* no unsigned 32-bit support in SDL */
  84
  85     case AUDIO_FORMAT_F32:
  86         return AUDIO_F32LSB;
  87
  88     default:
  89         dolog ("Internal logic error: Bad audio format %d\n", fmt);
  90 #ifdef DEBUG_AUDIO
  91         abort ();
  92 #endif
  93         return AUDIO_U8;
  94     }
  95 }
  96
  97 static int sdl_to_audfmt(int sdlfmt, AudioFormat *fmt, int *endianness)
  98 {
  99     switch (sdlfmt) {
 100     case AUDIO_S8:
 101         *endianness = 0;
 102         *fmt = AUDIO_FORMAT_S8;
 103         break;
 104
 105     case AUDIO_U8:
 106         *endianness = 0;
 107         *fmt = AUDIO_FORMAT_U8;
 108         break;
 109
 110     case AUDIO_S16LSB:
 111         *endianness = 0;
 112         *fmt = AUDIO_FORMAT_S16;
 113         break;
 114
 115     case AUDIO_U16LSB:
 116         *endianness = 0;
 117         *fmt = AUDIO_FORMAT_U16;
 118         break;
 119
 120     case AUDIO_S16MSB:
 121         *endianness = 1;
 122         *fmt = AUDIO_FORMAT_S16;
 123         break;
 124
 125     case AUDIO_U16MSB:
 126         *endianness = 1;
 127         *fmt = AUDIO_FORMAT_U16;
 128         break;
 129
 130     case AUDIO_S32LSB:
 131         *endianness = 0;
 132         *fmt = AUDIO_FORMAT_S32;
 133         break;
 134
 135     case AUDIO_S32MSB:
 136         *endianness = 1;
 137         *fmt = AUDIO_FORMAT_S32;
 138         break;
 139
 140     case AUDIO_F32LSB:
 141         *endianness = 0;
 142         *fmt = AUDIO_FORMAT_F32;
 143         break;
 144
 145     case AUDIO_F32MSB:
 146         *endianness = 1;
 147         *fmt = AUDIO_FORMAT_F32;
 148         break;
 149
 150     default:
 151         dolog ("Unrecognized SDL audio format %d\n", sdlfmt);
 152         return -1;
 153     }
 154
 155     return 0;
 156 }
 157
 158 static int sdl_open (SDL_AudioSpec *req, SDL_AudioSpec *obt)
 159 {
 160     int status;
 161 #ifndef _WIN32
 162     int err;
 163     sigset_t new, old;
 164
 165     /* Make sure potential threads created by SDL don't hog signals.  */
 166     err = sigfillset (&new);
 167     if (err) {
 168         dolog ("sdl_open: sigfillset failed: %s\n", strerror (errno));
 169         return -1;
 170     }
 171     err = pthread_sigmask (SIG_BLOCK, &new, &old);
 172     if (err) {
 173         dolog ("sdl_open: pthread_sigmask failed: %s\n", strerror (err));
 174         return -1;
 175     }
 176 #endif
 177
 178     status = SDL_OpenAudio (req, obt);
 179     if (status) {
 180         sdl_logerr ("SDL_OpenAudio failed\n");
 181     }
 182
 183 #ifndef _WIN32
 184     err = pthread_sigmask (SIG_SETMASK, &old, NULL);
 185     if (err) {
 186         dolog ("sdl_open: pthread_sigmask (restore) failed: %s\n",
 187                strerror (errno));
 188         /* We have failed to restore original signal mask, all bets are off,
 189            so exit the process */
 190         exit (EXIT_FAILURE);
 191     }
 192 #endif
 193     return status;
 194 }
 195
 196 static void sdl_close (SDLAudioState *s)
 197 {
 198     if (s->initialized) {
 199         SDL_LockAudio();
 200         s->exit = 1;
 201         SDL_UnlockAudio();
 202         SDL_PauseAudio (1);
 203         SDL_CloseAudio ();
 204         s->initialized = 0;
 205     }
 206 }
 207
 208 static void sdl_callback (void *opaque, Uint8 *buf, int len)
 209 {
 210     SDLVoiceOut *sdl = opaque;
 211     SDLAudioState *s = &glob_sdl;
 212     HWVoiceOut *hw = &sdl->hw;
 213
 214     if (s->exit) {
 215         return;
 216     }
 217
 218     /* dolog ("in callback samples=%zu live=%zu\n", samples, sdl->live); */
 219
 220     while (hw->pending_emul && len) {
 221         size_t write_len;
 222         ssize_t start = ((ssize_t) hw->pos_emul) - hw->pending_emul;
 223         if (start < 0) {
 224             start += hw->size_emul;
 225         }
 226         assert(start >= 0 && start < hw->size_emul);
 227
 228         write_len = MIN(MIN(hw->pending_emul, len),
 229                         hw->size_emul - start);
 230
 231         memcpy(buf, hw->buf_emul + start, write_len);
 232         hw->pending_emul -= write_len;
 233         len -= write_len;
 234         buf += write_len;
 235     }
 236
 237     /* clear remaining buffer that we couldn't fill with data */
 238     if (len) {
 239         memset(buf, 0, len);
 240     }
 241 }
 242
 243 #define SDL_WRAPPER_FUNC(name, ret_type, args_decl, args, fail, unlock) \
 244     static ret_type glue(sdl_, name)args_decl                           \
 245     {                                                                   \
 246         ret_type ret;                                                   \
 247                                                                         \
 248         SDL_LockAudio();                                                \
 249                                                                         \
 250         ret = glue(audio_generic_, name)args;                           \
 251                                                                         \
 252         SDL_UnlockAudio();                                              \
 253         return ret;                                                     \
 254     }
 255
 256 SDL_WRAPPER_FUNC(get_buffer_out, void *, (HWVoiceOut *hw, size_t *size),
 257                  (hw, size), *size = 0, sdl_unlock)
 258 SDL_WRAPPER_FUNC(put_buffer_out, size_t,
 259                  (HWVoiceOut *hw, void *buf, size_t size), (hw, buf, size),
 260                  /*nothing*/, sdl_unlock_and_post)
 261 SDL_WRAPPER_FUNC(write, size_t,
 262                  (HWVoiceOut *hw, void *buf, size_t size), (hw, buf, size),
 263                  /*nothing*/, sdl_unlock_and_post)
 264
 265 #undef SDL_WRAPPER_FUNC
 266
 267 static void sdl_fini_out (HWVoiceOut *hw)
 268 {
 269     (void) hw;
 270
 271     sdl_close (&glob_sdl);
 272 }
 273
 274 static int sdl_init_out(HWVoiceOut *hw, struct audsettings *as,
 275                         void *drv_opaque)
 276 {
 277     SDLVoiceOut *sdl = (SDLVoiceOut *) hw;
 278     SDLAudioState *s = &glob_sdl;
 279     SDL_AudioSpec req, obt;
 280     int endianness;
 281     int err;
 282     AudioFormat effective_fmt;
 283     struct audsettings obt_as;
 284
 285     req.freq = as->freq;
 286     req.format = aud_to_sdlfmt (as->fmt);
 287     req.channels = as->nchannels;
 288     req.samples = audio_buffer_samples(s->dev->u.sdl.out, as, 11610);
 289     req.callback = sdl_callback;
 290     req.userdata = sdl;
 291
 292     if (sdl_open (&req, &obt)) {
 293         return -1;
 294     }
 295
 296     err = sdl_to_audfmt(obt.format, &effective_fmt, &endianness);
 297     if (err) {
 298         sdl_close (s);
 299         return -1;
 300     }
 301
 302     obt_as.freq = obt.freq;
 303     obt_as.nchannels = obt.channels;
 304     obt_as.fmt = effective_fmt;
 305     obt_as.endianness = endianness;
 306
 307     audio_pcm_init_info (&hw->info, &obt_as);
 308     hw->samples = obt.samples;
 309
 310     s->initialized = 1;
 311     s->exit = 0;
 312     SDL_PauseAudio (0);
 313     return 0;
 314 }
 315
 316 static void sdl_enable_out(HWVoiceOut *hw, bool enable)
 317 {
 318     SDL_PauseAudio(!enable);
 319 }
 320
 321 static void *sdl_audio_init(Audiodev *dev)
 322 {
 323     SDLAudioState *s = &glob_sdl;
 324     if (s->driver_created) {
 325         sdl_logerr("Can't create multiple sdl backends\n");
 326         return NULL;
 327     }
 328
 329     if (SDL_InitSubSystem (SDL_INIT_AUDIO)) {
 330         sdl_logerr ("SDL failed to initialize audio subsystem\n");
 331         return NULL;
 332     }
 333
 334     s->driver_created = true;
 335     s->dev = dev;
 336     return s;
 337 }
 338
 339 static void sdl_audio_fini (void *opaque)
 340 {
 341     SDLAudioState *s = opaque;
 342     sdl_close (s);
 343     SDL_QuitSubSystem (SDL_INIT_AUDIO);
 344     s->driver_created = false;
 345     s->dev = NULL;
 346 }
 347
 348 static struct audio_pcm_ops sdl_pcm_ops = {
 349     .init_out = sdl_init_out,
 350     .fini_out = sdl_fini_out,
 351   /* wrapper for audio_generic_write */
 352     .write    = sdl_write,
 353   /* wrapper for audio_generic_get_buffer_out */
 354     .get_buffer_out = sdl_get_buffer_out,
 355   /* wrapper for audio_generic_put_buffer_out */
 356     .put_buffer_out = sdl_put_buffer_out,
 357     .enable_out = sdl_enable_out,
 358 };
 359
 360 static struct audio_driver sdl_audio_driver = {
 361     .name           = "sdl",
 362     .descr          = "SDL http://www.libsdl.org",
 363     .init           = sdl_audio_init,
 364     .fini           = sdl_audio_fini,
 365     .pcm_ops        = &sdl_pcm_ops,
 366     .can_be_default = 1,
 367     .max_voices_out = 1,
 368     .max_voices_in  = 0,
 369     .voice_size_out = sizeof (SDLVoiceOut),
 370     .voice_size_in  = 0
 371 };
 372
 373 static void register_audio_sdl(void)
 374 {
 375     audio_driver_register(&sdl_audio_driver);
 376 }
 377 type_init(register_audio_sdl);