Mercurial > sdl-ios-xcode
view src/audio/SDL_audio.c @ 2198:fe19afb86473
Split acinclude.m4 into its component parts for easy updating
author | Sam Lantinga <slouken@libsdl.org> |
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date | Sun, 15 Jul 2007 01:51:11 +0000 |
parents | a5f11bc178b4 |
children | 60b4c52a7906 |
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/* SDL - Simple DirectMedia Layer Copyright (C) 1997-2006 Sam Lantinga This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA Sam Lantinga slouken@libsdl.org */ #include "SDL_config.h" /* Allow access to a raw mixing buffer */ #include "SDL.h" #include "SDL_audio_c.h" #include "SDL_audiomem.h" #include "SDL_sysaudio.h" #define _THIS SDL_AudioDevice *this static SDL_AudioDriver current_audio; static SDL_AudioDevice *open_devices[16]; /* !!! FIXME: These are wordy and unlocalized... */ #define DEFAULT_OUTPUT_DEVNAME "System audio output device" #define DEFAULT_INPUT_DEVNAME "System audio capture device" /* * Not all of these will be compiled and linked in, but it's convenient * to have a complete list here and saves yet-another block of #ifdefs... * Please see bootstrap[], below, for the actual #ifdef mess. */ extern AudioBootStrap BSD_AUDIO_bootstrap; extern AudioBootStrap DSP_bootstrap; extern AudioBootStrap DMA_bootstrap; extern AudioBootStrap ALSA_bootstrap; extern AudioBootStrap QNXNTOAUDIO_bootstrap; extern AudioBootStrap SUNAUDIO_bootstrap; extern AudioBootStrap DMEDIA_bootstrap; extern AudioBootStrap ARTS_bootstrap; extern AudioBootStrap ESD_bootstrap; extern AudioBootStrap NAS_bootstrap; extern AudioBootStrap DSOUND_bootstrap; extern AudioBootStrap WINWAVEOUT_bootstrap; extern AudioBootStrap PAUDIO_bootstrap; extern AudioBootStrap BEOSAUDIO_bootstrap; extern AudioBootStrap COREAUDIO_bootstrap; extern AudioBootStrap SNDMGR_bootstrap; extern AudioBootStrap MINTAUDIO_GSXB_bootstrap; extern AudioBootStrap MINTAUDIO_MCSN_bootstrap; extern AudioBootStrap MINTAUDIO_STFA_bootstrap; extern AudioBootStrap MINTAUDIO_XBIOS_bootstrap; extern AudioBootStrap MINTAUDIO_DMA8_bootstrap; extern AudioBootStrap DISKAUD_bootstrap; extern AudioBootStrap DUMMYAUD_bootstrap; extern AudioBootStrap DCAUD_bootstrap; extern AudioBootStrap MMEAUDIO_bootstrap; extern AudioBootStrap DART_bootstrap; /* Available audio drivers */ static AudioBootStrap *bootstrap[] = { #if SDL_AUDIO_DRIVER_BSD &BSD_AUDIO_bootstrap, #endif #if SDL_AUDIO_DRIVER_OSS &DSP_bootstrap, &DMA_bootstrap, #endif #if SDL_AUDIO_DRIVER_ALSA &ALSA_bootstrap, #endif #if SDL_AUDIO_DRIVER_QNXNTO &QNXNTOAUDIO_bootstrap, #endif #if SDL_AUDIO_DRIVER_SUNAUDIO &SUNAUDIO_bootstrap, #endif #if SDL_AUDIO_DRIVER_DMEDIA &DMEDIA_bootstrap, #endif #if SDL_AUDIO_DRIVER_ARTS &ARTS_bootstrap, #endif #if SDL_AUDIO_DRIVER_ESD &ESD_bootstrap, #endif #if SDL_AUDIO_DRIVER_NAS &NAS_bootstrap, #endif #if SDL_AUDIO_DRIVER_DSOUND &DSOUND_bootstrap, #endif #if SDL_AUDIO_DRIVER_WINWAVEOUT &WINWAVEOUT_bootstrap, #endif #if SDL_AUDIO_DRIVER_PAUDIO &PAUDIO_bootstrap, #endif #if SDL_AUDIO_DRIVER_BEOSAUDIO &BEOSAUDIO_bootstrap, #endif #if SDL_AUDIO_DRIVER_COREAUDIO &COREAUDIO_bootstrap, #endif #if SDL_AUDIO_DRIVER_SNDMGR &SNDMGR_bootstrap, #endif #if SDL_AUDIO_DRIVER_MINT &MINTAUDIO_GSXB_bootstrap, &MINTAUDIO_MCSN_bootstrap, &MINTAUDIO_STFA_bootstrap, &MINTAUDIO_XBIOS_bootstrap, &MINTAUDIO_DMA8_bootstrap, #endif #if SDL_AUDIO_DRIVER_DISK &DISKAUD_bootstrap, #endif #if SDL_AUDIO_DRIVER_DUMMY &DUMMYAUD_bootstrap, #endif #if SDL_AUDIO_DRIVER_DC &DCAUD_bootstrap, #endif #if SDL_AUDIO_DRIVER_MMEAUDIO &MMEAUDIO_bootstrap, #endif #if SDL_AUDIO_DRIVER_DART &DART_bootstrap, #endif NULL }; static SDL_AudioDevice * get_audio_device(SDL_AudioDeviceID id) { id--; if ((id >= SDL_arraysize(open_devices)) || (open_devices[id] == NULL)) { SDL_SetError("Invalid audio device ID"); return NULL; } return open_devices[id]; } /* stubs for audio drivers that don't need a specific entry point... */ static int SDL_AudioDetectDevices_Default(int iscapture) { return -1; } static void SDL_AudioThreadInit_Default(_THIS) { /* no-op. */ } static void SDL_AudioWaitDevice_Default(_THIS) { /* no-op. */ } static void SDL_AudioPlayDevice_Default(_THIS) { /* no-op. */ } static Uint8 * SDL_AudioGetDeviceBuf_Default(_THIS) { return NULL; } static void SDL_AudioWaitDone_Default(_THIS) { /* no-op. */ } static void SDL_AudioCloseDevice_Default(_THIS) { /* no-op. */ } static void SDL_AudioDeinitialize_Default(void) { /* no-op. */ } static int SDL_AudioOpenDevice_Default(_THIS, const char *devname, int iscapture) { return 0; } static const char * SDL_AudioGetDeviceName_Default(int index, int iscapture) { SDL_SetError("No such device"); return NULL; } static void SDL_AudioLockDevice_Default(SDL_AudioDevice * device) { if (device->thread && (SDL_ThreadID() == device->threadid)) { return; } SDL_mutexP(device->mixer_lock); } static void SDL_AudioUnlockDevice_Default(SDL_AudioDevice * device) { if (device->thread && (SDL_ThreadID() == device->threadid)) { return; } SDL_mutexV(device->mixer_lock); } static void finalize_audio_entry_points(void) { /* * Fill in stub functions for unused driver entry points. This lets us * blindly call them without having to check for validity first. */ #define FILL_STUB(x) \ if (current_audio.impl.x == NULL) { \ current_audio.impl.x = SDL_Audio##x##_Default; \ } FILL_STUB(DetectDevices); FILL_STUB(GetDeviceName); FILL_STUB(OpenDevice); FILL_STUB(ThreadInit); FILL_STUB(WaitDevice); FILL_STUB(PlayDevice); FILL_STUB(GetDeviceBuf); FILL_STUB(WaitDone); FILL_STUB(CloseDevice); FILL_STUB(LockDevice); FILL_STUB(UnlockDevice); FILL_STUB(Deinitialize); #undef FILL_STUB } /* The general mixing thread function */ int SDLCALL SDL_RunAudio(void *devicep) { SDL_AudioDevice *device = (SDL_AudioDevice *) devicep; Uint8 *stream; int stream_len; void *udata; void (SDLCALL * fill) (void *userdata, Uint8 * stream, int len); int silence; /* Perform any thread setup */ device->threadid = SDL_ThreadID(); current_audio.impl.ThreadInit(device); /* Set up the mixing function */ fill = device->spec.callback; udata = device->spec.userdata; if (device->convert.needed) { if (device->convert.src_format == AUDIO_U8) { silence = 0x80; } else { silence = 0; } stream_len = device->convert.len; } else { silence = device->spec.silence; stream_len = device->spec.size; } /* Loop, filling the audio buffers */ while (device->enabled) { /* Fill the current buffer with sound */ if (device->convert.needed) { if (device->convert.buf) { stream = device->convert.buf; } else { continue; } } else { stream = current_audio.impl.GetDeviceBuf(device); if (stream == NULL) { stream = device->fake_stream; } } if (!device->paused) { SDL_mutexP(device->mixer_lock); (*fill) (udata, stream, stream_len); SDL_mutexV(device->mixer_lock); } /* Convert the audio if necessary */ if (device->convert.needed) { SDL_ConvertAudio(&device->convert); stream = current_audio.impl.GetDeviceBuf(device); if (stream == NULL) { stream = device->fake_stream; } SDL_memcpy(stream, device->convert.buf, device->convert.len_cvt); } /* Ready current buffer for play and change current buffer */ if (stream != device->fake_stream) { current_audio.impl.PlayDevice(device); } /* Wait for an audio buffer to become available */ if (stream == device->fake_stream) { SDL_Delay((device->spec.samples * 1000) / device->spec.freq); } else { current_audio.impl.WaitDevice(device); } } /* Wait for the audio to drain.. */ current_audio.impl.WaitDone(device); return (0); } static SDL_AudioFormat SDL_ParseAudioFormat(const char *string) { #define CHECK_FMT_STRING(x) if (SDL_strcmp(string, #x) == 0) return AUDIO_##x CHECK_FMT_STRING(U8); CHECK_FMT_STRING(S8); CHECK_FMT_STRING(U16LSB); CHECK_FMT_STRING(S16LSB); CHECK_FMT_STRING(U16MSB); CHECK_FMT_STRING(S16MSB); CHECK_FMT_STRING(U16SYS); CHECK_FMT_STRING(S16SYS); CHECK_FMT_STRING(U16); CHECK_FMT_STRING(S16); CHECK_FMT_STRING(S32LSB); CHECK_FMT_STRING(S32MSB); CHECK_FMT_STRING(S32SYS); CHECK_FMT_STRING(S32); CHECK_FMT_STRING(F32LSB); CHECK_FMT_STRING(F32MSB); CHECK_FMT_STRING(F32SYS); CHECK_FMT_STRING(F32); #undef CHECK_FMT_STRING return 0; } int SDL_GetNumAudioDrivers(void) { return (SDL_arraysize(bootstrap) - 1); } const char * SDL_GetAudioDriver(int index) { if (index >= 0 && index < SDL_GetNumAudioDrivers()) { return (bootstrap[index]->name); } return (NULL); } int SDL_AudioInit(const char *driver_name) { int i = 0; int initialized = 0; int tried_to_init = 0; if (SDL_WasInit(SDL_INIT_AUDIO)) { SDL_AudioQuit(); /* shutdown driver if already running. */ } SDL_memset(¤t_audio, '\0', sizeof(current_audio)); SDL_memset(open_devices, '\0', sizeof(open_devices)); /* Select the proper audio driver */ if (driver_name == NULL) { driver_name = SDL_getenv("SDL_AUDIODRIVER"); } for (i = 0; (!initialized) && (bootstrap[i]); ++i) { /* make sure we should even try this driver before doing so... */ const AudioBootStrap *backend = bootstrap[i]; if (((driver_name) && (SDL_strcasecmp(backend->name, driver_name))) || ((!driver_name) && (backend->demand_only))) { continue; } tried_to_init = 1; SDL_memset(¤t_audio, 0, sizeof(current_audio)); current_audio.name = backend->name; current_audio.desc = backend->desc; initialized = backend->init(¤t_audio.impl); } if (!initialized) { /* specific drivers will set the error message if they fail... */ if (!tried_to_init) { if (driver_name) { SDL_SetError("%s not available", driver_name); } else { SDL_SetError("No available audio device"); } } SDL_memset(¤t_audio, 0, sizeof(current_audio)); return (-1); /* No driver was available, so fail. */ } finalize_audio_entry_points(); return (0); } /* * Get the current audio driver name */ const char * SDL_GetCurrentAudioDriver() { return current_audio.name; } int SDL_GetNumAudioDevices(int iscapture) { if (!SDL_WasInit(SDL_INIT_AUDIO)) { return -1; } if ((iscapture) && (!current_audio.impl.HasCaptureSupport)) { return 0; } if ((iscapture) && (current_audio.impl.OnlyHasDefaultInputDevice)) { return 1; } if ((!iscapture) && (current_audio.impl.OnlyHasDefaultOutputDevice)) { return 1; } return current_audio.impl.DetectDevices(iscapture); } const char * SDL_GetAudioDeviceName(int index, int iscapture) { if (!SDL_WasInit(SDL_INIT_AUDIO)) { SDL_SetError("Audio subsystem is not initialized"); return NULL; } if ((iscapture) && (!current_audio.impl.HasCaptureSupport)) { SDL_SetError("No capture support"); return NULL; } if (index < 0) { SDL_SetError("No such device"); return NULL; } if ((iscapture) && (current_audio.impl.OnlyHasDefaultInputDevice)) { return DEFAULT_INPUT_DEVNAME; } if ((!iscapture) && (current_audio.impl.OnlyHasDefaultOutputDevice)) { return DEFAULT_OUTPUT_DEVNAME; } return current_audio.impl.GetDeviceName(index, iscapture); } static void close_audio_device(SDL_AudioDevice * device) { device->enabled = 0; if (device->thread != NULL) { SDL_WaitThread(device->thread, NULL); } if (device->mixer_lock != NULL) { SDL_DestroyMutex(device->mixer_lock); } if (device->fake_stream != NULL) { SDL_FreeAudioMem(device->fake_stream); } if (device->convert.needed) { SDL_FreeAudioMem(device->convert.buf); } if (device->opened) { current_audio.impl.CloseDevice(device); device->opened = 0; } SDL_FreeAudioMem(device); } /* * Sanity check desired AudioSpec for SDL_OpenAudio() in (orig). * Fills in a sanitized copy in (prepared). * Returns non-zero if okay, zero on fatal parameters in (orig). */ static int prepare_audiospec(const SDL_AudioSpec * orig, SDL_AudioSpec * prepared) { SDL_memcpy(prepared, orig, sizeof(SDL_AudioSpec)); if (orig->callback == NULL) { SDL_SetError("SDL_OpenAudio() passed a NULL callback"); return 0; } if (orig->freq == 0) { const char *env = SDL_getenv("SDL_AUDIO_FREQUENCY"); if ((!env) || ((prepared->freq = SDL_atoi(env)) == 0)) { prepared->freq = 22050; /* a reasonable default */ } } if (orig->format == 0) { const char *env = SDL_getenv("SDL_AUDIO_FORMAT"); if ((!env) || ((prepared->format = SDL_ParseAudioFormat(env)) == 0)) { prepared->format = AUDIO_S16; /* a reasonable default */ } } switch (orig->channels) { case 0:{ const char *env = SDL_getenv("SDL_AUDIO_CHANNELS"); if ((!env) || ((prepared->channels = (Uint8) SDL_atoi(env)) == 0)) { prepared->channels = 2; /* a reasonable default */ } break; } case 1: /* Mono */ case 2: /* Stereo */ case 4: /* surround */ case 6: /* surround with center and lfe */ break; default: SDL_SetError("Unsupported number of audio channels."); return 0; } if (orig->samples == 0) { const char *env = SDL_getenv("SDL_AUDIO_SAMPLES"); if ((!env) || ((prepared->samples = (Uint16) SDL_atoi(env)) == 0)) { /* Pick a default of ~46 ms at desired frequency */ /* !!! FIXME: remove this when the non-Po2 resampling is in. */ const int samples = (prepared->freq / 1000) * 46; int power2 = 1; while (power2 < samples) { power2 *= 2; } prepared->samples = power2; } } /* Calculate the silence and size of the audio specification */ SDL_CalculateAudioSpec(prepared); return 1; } static SDL_AudioDeviceID open_audio_device(const char *devname, int iscapture, const SDL_AudioSpec * _desired, SDL_AudioSpec * obtained, int min_id) { SDL_AudioDeviceID id = 0; SDL_AudioSpec desired; SDL_AudioDevice *device; int i = 0; if (!SDL_WasInit(SDL_INIT_AUDIO)) { SDL_SetError("Audio subsystem is not initialized"); return 0; } if ((iscapture) && (!current_audio.impl.HasCaptureSupport)) { SDL_SetError("No capture support"); return 0; } if (!prepare_audiospec(_desired, &desired)) { return 0; } /* If app doesn't care about a specific device, let the user override. */ if (devname == NULL) { devname = SDL_getenv("SDL_AUDIO_DEVICE_NAME"); } /* * Catch device names at the high level for the simple case... * This lets us have a basic "device enumeration" for systems that * don't have multiple devices, but makes sure the device name is * always NULL when it hits the low level. * * Also make sure that the simple case prevents multiple simultaneous * opens of the default system device. */ if ((iscapture) && (current_audio.impl.OnlyHasDefaultInputDevice)) { if ((devname) && (SDL_strcmp(devname, DEFAULT_INPUT_DEVNAME) != 0)) { SDL_SetError("No such device"); return 0; } devname = NULL; for (i = 0; i < SDL_arraysize(open_devices); i++) { if ((open_devices[i]) && (open_devices[i]->iscapture)) { SDL_SetError("Audio device already open"); return 0; } } } if ((!iscapture) && (current_audio.impl.OnlyHasDefaultOutputDevice)) { if ((devname) && (SDL_strcmp(devname, DEFAULT_OUTPUT_DEVNAME) != 0)) { SDL_SetError("No such device"); return 0; } devname = NULL; for (i = 0; i < SDL_arraysize(open_devices); i++) { if ((open_devices[i]) && (!open_devices[i]->iscapture)) { SDL_SetError("Audio device already open"); return 0; } } } device = (SDL_AudioDevice *) SDL_AllocAudioMem(sizeof(SDL_AudioDevice)); if (device == NULL) { SDL_OutOfMemory(); return 0; } SDL_memset(device, '\0', sizeof(SDL_AudioDevice)); SDL_memcpy(&device->spec, &desired, sizeof(SDL_AudioSpec)); device->enabled = 1; device->paused = 1; device->iscapture = iscapture; /* Create a semaphore for locking the sound buffers */ if (!current_audio.impl.SkipMixerLock) { device->mixer_lock = SDL_CreateMutex(); if (device->mixer_lock == NULL) { close_audio_device(device); SDL_SetError("Couldn't create mixer lock"); return 0; } } if (!current_audio.impl.OpenDevice(device, devname, iscapture)) { close_audio_device(device); return 0; } device->opened = 1; /* If the audio driver changes the buffer size, accept it */ if (device->spec.samples != desired.samples) { desired.samples = device->spec.samples; SDL_CalculateAudioSpec(&device->spec); } /* Allocate a fake audio memory buffer */ device->fake_stream = SDL_AllocAudioMem(device->spec.size); if (device->fake_stream == NULL) { close_audio_device(device); SDL_OutOfMemory(); return 0; } /* See if we need to do any conversion */ if (obtained != NULL) { SDL_memcpy(obtained, &device->spec, sizeof(SDL_AudioSpec)); } else if (desired.freq != device->spec.freq || desired.format != device->spec.format || desired.channels != device->spec.channels) { /* Build an audio conversion block */ if (SDL_BuildAudioCVT(&device->convert, desired.format, desired.channels, desired.freq, device->spec.format, device->spec.channels, device->spec.freq) < 0) { close_audio_device(device); return 0; } if (device->convert.needed) { device->convert.len = (int) (((double) desired.size) / device->convert.len_ratio); device->convert.buf = (Uint8 *) SDL_AllocAudioMem(device->convert.len * device->convert.len_mult); if (device->convert.buf == NULL) { close_audio_device(device); SDL_OutOfMemory(); return 0; } } } /* Find an available device ID and store the structure... */ for (id = min_id - 1; id < SDL_arraysize(open_devices); id++) { if (open_devices[id] == NULL) { open_devices[id] = device; break; } } if (id == SDL_arraysize(open_devices)) { SDL_SetError("Too many open audio devices"); close_audio_device(device); return 0; } /* Start the audio thread if necessary */ if (!current_audio.impl.ProvidesOwnCallbackThread) { /* Start the audio thread */ /* !!! FIXME: this is nasty. */ #if (defined(__WIN32__) && !defined(_WIN32_WCE)) && !defined(HAVE_LIBC) #undef SDL_CreateThread device->thread = SDL_CreateThread(SDL_RunAudio, device, NULL, NULL); #else device->thread = SDL_CreateThread(SDL_RunAudio, device); #endif if (device->thread == NULL) { SDL_CloseAudioDevice(id + 1); SDL_SetError("Couldn't create audio thread"); return 0; } } return id + 1; } int SDL_OpenAudio(const SDL_AudioSpec * desired, SDL_AudioSpec * obtained) { SDL_AudioDeviceID id = 0; /* Start up the audio driver, if necessary. This is legacy behaviour! */ if (!SDL_WasInit(SDL_INIT_AUDIO)) { if (SDL_InitSubSystem(SDL_INIT_AUDIO) < 0) { return (-1); } } /* SDL_OpenAudio() is legacy and can only act on Device ID #1. */ if (open_devices[0] != NULL) { SDL_SetError("Audio device is already opened"); return (-1); } id = open_audio_device(NULL, 0, desired, obtained, 1); if (id > 1) { /* this should never happen in theory... */ SDL_CloseAudioDevice(id); SDL_SetError("Internal error"); /* MUST be Device ID #1! */ return (-1); } return ((id == 0) ? -1 : 0); } SDL_AudioDeviceID SDL_OpenAudioDevice(const char *device, int iscapture, const SDL_AudioSpec * desired, SDL_AudioSpec * obtained) { return open_audio_device(device, iscapture, desired, obtained, 2); } SDL_audiostatus SDL_GetAudioDeviceStatus(SDL_AudioDeviceID devid) { SDL_AudioDevice *device = get_audio_device(devid); SDL_audiostatus status = SDL_AUDIO_STOPPED; if (device && device->enabled) { if (device->paused) { status = SDL_AUDIO_PAUSED; } else { status = SDL_AUDIO_PLAYING; } } return (status); } SDL_audiostatus SDL_GetAudioStatus(void) { return SDL_GetAudioDeviceStatus(1); } void SDL_PauseAudioDevice(SDL_AudioDeviceID devid, int pause_on) { SDL_AudioDevice *device = get_audio_device(devid); if (device) { device->paused = pause_on; } } void SDL_PauseAudio(int pause_on) { SDL_PauseAudioDevice(1, pause_on); } void SDL_LockAudioDevice(SDL_AudioDeviceID devid) { /* Obtain a lock on the mixing buffers */ SDL_AudioDevice *device = get_audio_device(devid); if (device) { current_audio.impl.LockDevice(device); } } void SDL_LockAudio(void) { SDL_LockAudioDevice(1); } void SDL_UnlockAudioDevice(SDL_AudioDeviceID devid) { /* Obtain a lock on the mixing buffers */ SDL_AudioDevice *device = get_audio_device(devid); if (device) { current_audio.impl.UnlockDevice(device); } } void SDL_UnlockAudio(void) { SDL_UnlockAudioDevice(1); } void SDL_CloseAudioDevice(SDL_AudioDeviceID devid) { SDL_AudioDevice *device = get_audio_device(devid); if (device) { close_audio_device(device); open_devices[devid - 1] = NULL; } } void SDL_CloseAudio(void) { SDL_CloseAudioDevice(1); } void SDL_AudioQuit(void) { SDL_AudioDeviceID i; for (i = 0; i < SDL_arraysize(open_devices); i++) { SDL_CloseAudioDevice(i); } /* Free the driver data */ current_audio.impl.Deinitialize(); SDL_memset(¤t_audio, '\0', sizeof(current_audio)); SDL_memset(open_devices, '\0', sizeof(open_devices)); } #define NUM_FORMATS 10 static int format_idx; static int format_idx_sub; static SDL_AudioFormat format_list[NUM_FORMATS][NUM_FORMATS] = { {AUDIO_U8, AUDIO_S8, AUDIO_S16LSB, AUDIO_S16MSB, AUDIO_U16LSB, AUDIO_U16MSB, AUDIO_S32LSB, AUDIO_S32MSB, AUDIO_F32LSB, AUDIO_F32MSB}, {AUDIO_S8, AUDIO_U8, AUDIO_S16LSB, AUDIO_S16MSB, AUDIO_U16LSB, AUDIO_U16MSB, AUDIO_S32LSB, AUDIO_S32MSB, AUDIO_F32LSB, AUDIO_F32MSB}, {AUDIO_S16LSB, AUDIO_S16MSB, AUDIO_U16LSB, AUDIO_U16MSB, AUDIO_S32LSB, AUDIO_S32MSB, AUDIO_F32LSB, AUDIO_F32MSB, AUDIO_U8, AUDIO_S8}, {AUDIO_S16MSB, AUDIO_S16LSB, AUDIO_U16MSB, AUDIO_U16LSB, AUDIO_S32MSB, AUDIO_S32LSB, AUDIO_F32MSB, AUDIO_F32LSB, AUDIO_U8, AUDIO_S8}, {AUDIO_U16LSB, AUDIO_U16MSB, AUDIO_S16LSB, AUDIO_S16MSB, AUDIO_S32LSB, AUDIO_S32MSB, AUDIO_F32LSB, AUDIO_F32MSB, AUDIO_U8, AUDIO_S8}, {AUDIO_U16MSB, AUDIO_U16LSB, AUDIO_S16MSB, AUDIO_S16LSB, AUDIO_S32MSB, AUDIO_S32LSB, AUDIO_F32MSB, AUDIO_F32LSB, AUDIO_U8, AUDIO_S8}, {AUDIO_S32LSB, AUDIO_S32MSB, AUDIO_F32LSB, AUDIO_F32MSB, AUDIO_S16LSB, AUDIO_S16MSB, AUDIO_U16LSB, AUDIO_U16MSB, AUDIO_U8, AUDIO_S8}, {AUDIO_S32MSB, AUDIO_S32LSB, AUDIO_F32MSB, AUDIO_F32LSB, AUDIO_S16MSB, AUDIO_S16LSB, AUDIO_U16MSB, AUDIO_U16LSB, AUDIO_U8, AUDIO_S8}, {AUDIO_F32LSB, AUDIO_F32MSB, AUDIO_S32LSB, AUDIO_S32MSB, AUDIO_S16LSB, AUDIO_S16MSB, AUDIO_U16LSB, AUDIO_U16MSB, AUDIO_U8, AUDIO_S8}, {AUDIO_F32MSB, AUDIO_F32LSB, AUDIO_S32MSB, AUDIO_S32LSB, AUDIO_S16MSB, AUDIO_S16LSB, AUDIO_U16MSB, AUDIO_U16LSB, AUDIO_U8, AUDIO_S8}, }; SDL_AudioFormat SDL_FirstAudioFormat(SDL_AudioFormat format) { for (format_idx = 0; format_idx < NUM_FORMATS; ++format_idx) { if (format_list[format_idx][0] == format) { break; } } format_idx_sub = 0; return (SDL_NextAudioFormat()); } SDL_AudioFormat SDL_NextAudioFormat(void) { if ((format_idx == NUM_FORMATS) || (format_idx_sub == NUM_FORMATS)) { return (0); } return (format_list[format_idx][format_idx_sub++]); } void SDL_CalculateAudioSpec(SDL_AudioSpec * spec) { switch (spec->format) { case AUDIO_U8: spec->silence = 0x80; break; default: spec->silence = 0x00; break; } spec->size = SDL_AUDIO_BITSIZE(spec->format) / 8; spec->size *= spec->channels; spec->size *= spec->samples; } /* * Moved here from SDL_mixer.c, since it relies on internals of an opened * audio device (and is deprecated, by the way!). */ void SDL_MixAudio(Uint8 * dst, const Uint8 * src, Uint32 len, int volume) { /* Mix the user-level audio format */ SDL_AudioDevice *device = get_audio_device(1); if (device != NULL) { SDL_AudioFormat format; if (device->convert.needed) { format = device->convert.src_format; } else { format = device->spec.format; } SDL_MixAudioFormat(dst, src, format, len, volume); } } /* vi: set ts=4 sw=4 expandtab: */