Google Git
Sign in
fuchsia / third_party / sdl / ff6e25b3e75d5fa62f8201c67d7d0f10d5851c2d / . / src / audio / SDL_audio.c
blob: 6d7217278da510bbf3268be60d9a661d18a9be29 [file] [log] [blame]
/*
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 WAVEOUT_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_WAVEOUT
&WAVEOUT_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;
const int legacy_device = (device == open_devices[0]);
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;
}
}
/* New code should fill buffer or set it to silence themselves. */
if (legacy_device) {
SDL_memset(stream, silence, stream_len);
}
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 (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(&current_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(&current_audio, 0, sizeof (current_audio));
current_audio.name = backend->name;
current_audio.desc = backend->desc;
initialized = backend->init(&current_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(&current_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 = 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 = desired.size;
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(&current_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: */