qemu/audio/sdlaudio.c
<<
>>
Prefs
   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#endif
  36
  37#define AUDIO_CAP "sdl"
  38#include "audio_int.h"
  39
  40typedef struct SDLVoiceOut {
  41    HWVoiceOut hw;
  42    int live;
  43    int rpos;
  44    int decr;
  45} SDLVoiceOut;
  46
  47static struct {
  48    int nb_samples;
  49} conf = {
  50    .nb_samples = 1024
  51};
  52
  53static struct SDLAudioState {
  54    int exit;
  55    SDL_mutex *mutex;
  56    SDL_sem *sem;
  57    int initialized;
  58} glob_sdl;
  59typedef struct SDLAudioState SDLAudioState;
  60
  61static void GCC_FMT_ATTR (1, 2) sdl_logerr (const char *fmt, ...)
  62{
  63    va_list ap;
  64
  65    va_start (ap, fmt);
  66    AUD_vlog (AUDIO_CAP, fmt, ap);
  67    va_end (ap);
  68
  69    AUD_log (AUDIO_CAP, "Reason: %s\n", SDL_GetError ());
  70}
  71
  72static int sdl_lock (SDLAudioState *s, const char *forfn)
  73{
  74    if (SDL_LockMutex (s->mutex)) {
  75        sdl_logerr ("SDL_LockMutex for %s failed\n", forfn);
  76        return -1;
  77    }
  78    return 0;
  79}
  80
  81static int sdl_unlock (SDLAudioState *s, const char *forfn)
  82{
  83    if (SDL_UnlockMutex (s->mutex)) {
  84        sdl_logerr ("SDL_UnlockMutex for %s failed\n", forfn);
  85        return -1;
  86    }
  87    return 0;
  88}
  89
  90static int sdl_post (SDLAudioState *s, const char *forfn)
  91{
  92    if (SDL_SemPost (s->sem)) {
  93        sdl_logerr ("SDL_SemPost for %s failed\n", forfn);
  94        return -1;
  95    }
  96    return 0;
  97}
  98
  99static int sdl_wait (SDLAudioState *s, const char *forfn)
 100{
 101    if (SDL_SemWait (s->sem)) {
 102        sdl_logerr ("SDL_SemWait for %s failed\n", forfn);
 103        return -1;
 104    }
 105    return 0;
 106}
 107
 108static int sdl_unlock_and_post (SDLAudioState *s, const char *forfn)
 109{
 110    if (sdl_unlock (s, forfn)) {
 111        return -1;
 112    }
 113
 114    return sdl_post (s, forfn);
 115}
 116
 117static int aud_to_sdlfmt (audfmt_e fmt)
 118{
 119    switch (fmt) {
 120    case AUD_FMT_S8:
 121        return AUDIO_S8;
 122
 123    case AUD_FMT_U8:
 124        return AUDIO_U8;
 125
 126    case AUD_FMT_S16:
 127        return AUDIO_S16LSB;
 128
 129    case AUD_FMT_U16:
 130        return AUDIO_U16LSB;
 131
 132    default:
 133        dolog ("Internal logic error: Bad audio format %d\n", fmt);
 134#ifdef DEBUG_AUDIO
 135        abort ();
 136#endif
 137        return AUDIO_U8;
 138    }
 139}
 140
 141static int sdl_to_audfmt(int sdlfmt, audfmt_e *fmt, int *endianness)
 142{
 143    switch (sdlfmt) {
 144    case AUDIO_S8:
 145        *endianness = 0;
 146        *fmt = AUD_FMT_S8;
 147        break;
 148
 149    case AUDIO_U8:
 150        *endianness = 0;
 151        *fmt = AUD_FMT_U8;
 152        break;
 153
 154    case AUDIO_S16LSB:
 155        *endianness = 0;
 156        *fmt = AUD_FMT_S16;
 157        break;
 158
 159    case AUDIO_U16LSB:
 160        *endianness = 0;
 161        *fmt = AUD_FMT_U16;
 162        break;
 163
 164    case AUDIO_S16MSB:
 165        *endianness = 1;
 166        *fmt = AUD_FMT_S16;
 167        break;
 168
 169    case AUDIO_U16MSB:
 170        *endianness = 1;
 171        *fmt = AUD_FMT_U16;
 172        break;
 173
 174    default:
 175        dolog ("Unrecognized SDL audio format %d\n", sdlfmt);
 176        return -1;
 177    }
 178
 179    return 0;
 180}
 181
 182static int sdl_open (SDL_AudioSpec *req, SDL_AudioSpec *obt)
 183{
 184    int status;
 185#ifndef _WIN32
 186    int err;
 187    sigset_t new, old;
 188
 189    /* Make sure potential threads created by SDL don't hog signals.  */
 190    err = sigfillset (&new);
 191    if (err) {
 192        dolog ("sdl_open: sigfillset failed: %s\n", strerror (errno));
 193        return -1;
 194    }
 195    err = pthread_sigmask (SIG_BLOCK, &new, &old);
 196    if (err) {
 197        dolog ("sdl_open: pthread_sigmask failed: %s\n", strerror (err));
 198        return -1;
 199    }
 200#endif
 201
 202    status = SDL_OpenAudio (req, obt);
 203    if (status) {
 204        sdl_logerr ("SDL_OpenAudio failed\n");
 205    }
 206
 207#ifndef _WIN32
 208    err = pthread_sigmask (SIG_SETMASK, &old, NULL);
 209    if (err) {
 210        dolog ("sdl_open: pthread_sigmask (restore) failed: %s\n",
 211               strerror (errno));
 212        /* We have failed to restore original signal mask, all bets are off,
 213           so exit the process */
 214        exit (EXIT_FAILURE);
 215    }
 216#endif
 217    return status;
 218}
 219
 220static void sdl_close (SDLAudioState *s)
 221{
 222    if (s->initialized) {
 223        sdl_lock (s, "sdl_close");
 224        s->exit = 1;
 225        sdl_unlock_and_post (s, "sdl_close");
 226        SDL_PauseAudio (1);
 227        SDL_CloseAudio ();
 228        s->initialized = 0;
 229    }
 230}
 231
 232static void sdl_callback (void *opaque, Uint8 *buf, int len)
 233{
 234    SDLVoiceOut *sdl = opaque;
 235    SDLAudioState *s = &glob_sdl;
 236    HWVoiceOut *hw = &sdl->hw;
 237    int samples = len >> hw->info.shift;
 238
 239    if (s->exit) {
 240        return;
 241    }
 242
 243    while (samples) {
 244        int to_mix, decr;
 245
 246        /* dolog ("in callback samples=%d\n", samples); */
 247        sdl_wait (s, "sdl_callback");
 248        if (s->exit) {
 249            return;
 250        }
 251
 252        if (sdl_lock (s, "sdl_callback")) {
 253            return;
 254        }
 255
 256        if (audio_bug (AUDIO_FUNC, sdl->live < 0 || sdl->live > hw->samples)) {
 257            dolog ("sdl->live=%d hw->samples=%d\n",
 258                   sdl->live, hw->samples);
 259            return;
 260        }
 261
 262        if (!sdl->live) {
 263            goto again;
 264        }
 265
 266        /* dolog ("in callback live=%d\n", live); */
 267        to_mix = audio_MIN (samples, sdl->live);
 268        decr = to_mix;
 269        while (to_mix) {
 270            int chunk = audio_MIN (to_mix, hw->samples - hw->rpos);
 271            struct st_sample *src = hw->mix_buf + hw->rpos;
 272
 273            /* dolog ("in callback to_mix %d, chunk %d\n", to_mix, chunk); */
 274            hw->clip (buf, src, chunk);
 275            sdl->rpos = (sdl->rpos + chunk) % hw->samples;
 276            to_mix -= chunk;
 277            buf += chunk << hw->info.shift;
 278        }
 279        samples -= decr;
 280        sdl->live -= decr;
 281        sdl->decr += decr;
 282
 283    again:
 284        if (sdl_unlock (s, "sdl_callback")) {
 285            return;
 286        }
 287    }
 288    /* dolog ("done len=%d\n", len); */
 289}
 290
 291static int sdl_write_out (SWVoiceOut *sw, void *buf, int len)
 292{
 293    return audio_pcm_sw_write (sw, buf, len);
 294}
 295
 296static int sdl_run_out (HWVoiceOut *hw, int live)
 297{
 298    int decr;
 299    SDLVoiceOut *sdl = (SDLVoiceOut *) hw;
 300    SDLAudioState *s = &glob_sdl;
 301
 302    if (sdl_lock (s, "sdl_run_out")) {
 303        return 0;
 304    }
 305
 306    if (sdl->decr > live) {
 307        ldebug ("sdl->decr %d live %d sdl->live %d\n",
 308                sdl->decr,
 309                live,
 310                sdl->live);
 311    }
 312
 313    decr = audio_MIN (sdl->decr, live);
 314    sdl->decr -= decr;
 315
 316    sdl->live = live - decr;
 317    hw->rpos = sdl->rpos;
 318
 319    if (sdl->live > 0) {
 320        sdl_unlock_and_post (s, "sdl_run_out");
 321    }
 322    else {
 323        sdl_unlock (s, "sdl_run_out");
 324    }
 325    return decr;
 326}
 327
 328static void sdl_fini_out (HWVoiceOut *hw)
 329{
 330    (void) hw;
 331
 332    sdl_close (&glob_sdl);
 333}
 334
 335static int sdl_init_out (HWVoiceOut *hw, struct audsettings *as)
 336{
 337    SDLVoiceOut *sdl = (SDLVoiceOut *) hw;
 338    SDLAudioState *s = &glob_sdl;
 339    SDL_AudioSpec req, obt;
 340    int endianness;
 341    int err;
 342    audfmt_e effective_fmt;
 343    struct audsettings obt_as;
 344
 345    req.freq = as->freq;
 346    req.format = aud_to_sdlfmt (as->fmt);
 347    req.channels = as->nchannels;
 348    req.samples = conf.nb_samples;
 349    req.callback = sdl_callback;
 350    req.userdata = sdl;
 351
 352    if (sdl_open (&req, &obt)) {
 353        return -1;
 354    }
 355
 356    err = sdl_to_audfmt(obt.format, &effective_fmt, &endianness);
 357    if (err) {
 358        sdl_close (s);
 359        return -1;
 360    }
 361
 362    obt_as.freq = obt.freq;
 363    obt_as.nchannels = obt.channels;
 364    obt_as.fmt = effective_fmt;
 365    obt_as.endianness = endianness;
 366
 367    audio_pcm_init_info (&hw->info, &obt_as);
 368    hw->samples = obt.samples;
 369
 370    s->initialized = 1;
 371    s->exit = 0;
 372    SDL_PauseAudio (0);
 373    return 0;
 374}
 375
 376static int sdl_ctl_out (HWVoiceOut *hw, int cmd, ...)
 377{
 378    (void) hw;
 379
 380    switch (cmd) {
 381    case VOICE_ENABLE:
 382        SDL_PauseAudio (0);
 383        break;
 384
 385    case VOICE_DISABLE:
 386        SDL_PauseAudio (1);
 387        break;
 388    }
 389    return 0;
 390}
 391
 392static void *sdl_audio_init (void)
 393{
 394    SDLAudioState *s = &glob_sdl;
 395
 396    if (SDL_InitSubSystem (SDL_INIT_AUDIO)) {
 397        sdl_logerr ("SDL failed to initialize audio subsystem\n");
 398        return NULL;
 399    }
 400
 401    s->mutex = SDL_CreateMutex ();
 402    if (!s->mutex) {
 403        sdl_logerr ("Failed to create SDL mutex\n");
 404        SDL_QuitSubSystem (SDL_INIT_AUDIO);
 405        return NULL;
 406    }
 407
 408    s->sem = SDL_CreateSemaphore (0);
 409    if (!s->sem) {
 410        sdl_logerr ("Failed to create SDL semaphore\n");
 411        SDL_DestroyMutex (s->mutex);
 412        SDL_QuitSubSystem (SDL_INIT_AUDIO);
 413        return NULL;
 414    }
 415
 416    return s;
 417}
 418
 419static void sdl_audio_fini (void *opaque)
 420{
 421    SDLAudioState *s = opaque;
 422    sdl_close (s);
 423    SDL_DestroySemaphore (s->sem);
 424    SDL_DestroyMutex (s->mutex);
 425    SDL_QuitSubSystem (SDL_INIT_AUDIO);
 426}
 427
 428static struct audio_option sdl_options[] = {
 429    {
 430        .name  = "SAMPLES",
 431        .tag   = AUD_OPT_INT,
 432        .valp  = &conf.nb_samples,
 433        .descr = "Size of SDL buffer in samples"
 434    },
 435    { /* End of list */ }
 436};
 437
 438static struct audio_pcm_ops sdl_pcm_ops = {
 439    .init_out = sdl_init_out,
 440    .fini_out = sdl_fini_out,
 441    .run_out  = sdl_run_out,
 442    .write    = sdl_write_out,
 443    .ctl_out  = sdl_ctl_out,
 444};
 445
 446struct audio_driver sdl_audio_driver = {
 447    .name           = "sdl",
 448    .descr          = "SDL http://www.libsdl.org",
 449    .options        = sdl_options,
 450    .init           = sdl_audio_init,
 451    .fini           = sdl_audio_fini,
 452    .pcm_ops        = &sdl_pcm_ops,
 453    .can_be_default = 1,
 454    .max_voices_out = 1,
 455    .max_voices_in  = 0,
 456    .voice_size_out = sizeof (SDLVoiceOut),
 457    .voice_size_in  = 0
 458};
 459