704 lines
16 KiB
C
704 lines
16 KiB
C
/*
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SDL - Simple DirectMedia Layer
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Copyright (C) 1997-2012 Sam Lantinga
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This library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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This library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with this library; if not, write to the Free Software
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Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
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Sam Lantinga
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slouken@libsdl.org
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*/
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#include "SDL_config.h"
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/* Allow access to a raw mixing buffer */
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#include "SDL.h"
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#include "SDL_audio_c.h"
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#include "SDL_audiomem.h"
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#include "SDL_sysaudio.h"
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#ifdef __OS2__
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/* We'll need the DosSetPriority() API! */
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#define INCL_DOSPROCESS
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#include <os2.h>
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#endif
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/* Available audio drivers */
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static AudioBootStrap *bootstrap[] = {
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#if SDL_AUDIO_DRIVER_PULSE
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&PULSE_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_ALSA
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&ALSA_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_BSD
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&BSD_AUDIO_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_OSS
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&DSP_bootstrap,
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&DMA_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_QNXNTO
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&QNXNTOAUDIO_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_SUNAUDIO
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&SUNAUDIO_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_DMEDIA
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&DMEDIA_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_ARTS
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&ARTS_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_ESD
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&ESD_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_NAS
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&NAS_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_DSOUND
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&DSOUND_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_WAVEOUT
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&WAVEOUT_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_PAUD
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&Paud_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_BAUDIO
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&BAUDIO_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_COREAUDIO
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&COREAUDIO_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_SNDMGR
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&SNDMGR_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_MINT
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&MINTAUDIO_GSXB_bootstrap,
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&MINTAUDIO_MCSN_bootstrap,
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&MINTAUDIO_STFA_bootstrap,
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&MINTAUDIO_XBIOS_bootstrap,
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&MINTAUDIO_DMA8_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_DISK
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&DISKAUD_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_DUMMY
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&DUMMYAUD_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_DC
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&DCAUD_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_NDS
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&NDSAUD_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_MMEAUDIO
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&MMEAUDIO_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_DART
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&DART_bootstrap,
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#endif
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#if SDL_AUDIO_DRIVER_EPOCAUDIO
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&EPOCAudio_bootstrap,
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#endif
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NULL
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};
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SDL_AudioDevice *current_audio = NULL;
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/* Various local functions */
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int SDL_AudioInit(const char *driver_name);
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void SDL_AudioQuit(void);
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/* The general mixing thread function */
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int SDLCALL SDL_RunAudio(void *audiop)
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{
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SDL_AudioDevice *audio = (SDL_AudioDevice *)audiop;
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Uint8 *stream;
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int stream_len;
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void *udata;
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void (SDLCALL *fill)(void *userdata,Uint8 *stream, int len);
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int silence;
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/* Perform any thread setup */
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if ( audio->ThreadInit ) {
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audio->ThreadInit(audio);
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}
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audio->threadid = SDL_ThreadID();
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/* Set up the mixing function */
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fill = audio->spec.callback;
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udata = audio->spec.userdata;
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if ( audio->convert.needed ) {
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if ( audio->convert.src_format == AUDIO_U8 ) {
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silence = 0x80;
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} else {
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silence = 0;
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}
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stream_len = audio->convert.len;
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} else {
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silence = audio->spec.silence;
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stream_len = audio->spec.size;
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}
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#ifdef __OS2__
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/* Increase the priority of this thread to make sure that
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the audio will be continuous all the time! */
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#ifdef USE_DOSSETPRIORITY
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if (SDL_getenv("SDL_USE_TIMECRITICAL_AUDIO"))
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{
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#ifdef DEBUG_BUILD
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printf("[SDL_RunAudio] : Setting priority to TimeCritical+0! (TID%d)\n", SDL_ThreadID());
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#endif
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DosSetPriority(PRTYS_THREAD, PRTYC_TIMECRITICAL, 0, 0);
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}
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else
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{
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#ifdef DEBUG_BUILD
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printf("[SDL_RunAudio] : Setting priority to ForegroundServer+0! (TID%d)\n", SDL_ThreadID());
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#endif
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DosSetPriority(PRTYS_THREAD, PRTYC_FOREGROUNDSERVER, 0, 0);
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}
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#endif
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#endif
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/* Loop, filling the audio buffers */
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while ( audio->enabled ) {
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/* Fill the current buffer with sound */
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if ( audio->convert.needed ) {
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if ( audio->convert.buf ) {
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stream = audio->convert.buf;
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} else {
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continue;
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}
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} else {
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stream = audio->GetAudioBuf(audio);
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if ( stream == NULL ) {
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stream = audio->fake_stream;
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}
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}
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SDL_memset(stream, silence, stream_len);
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if ( ! audio->paused ) {
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SDL_mutexP(audio->mixer_lock);
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(*fill)(udata, stream, stream_len);
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SDL_mutexV(audio->mixer_lock);
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}
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/* Convert the audio if necessary */
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if ( audio->convert.needed ) {
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SDL_ConvertAudio(&audio->convert);
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stream = audio->GetAudioBuf(audio);
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if ( stream == NULL ) {
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stream = audio->fake_stream;
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}
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SDL_memcpy(stream, audio->convert.buf,
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audio->convert.len_cvt);
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}
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/* Ready current buffer for play and change current buffer */
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if ( stream != audio->fake_stream ) {
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audio->PlayAudio(audio);
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}
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/* Wait for an audio buffer to become available */
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if ( stream == audio->fake_stream ) {
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SDL_Delay((audio->spec.samples*1000)/audio->spec.freq);
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} else {
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audio->WaitAudio(audio);
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}
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}
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/* Wait for the audio to drain.. */
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if ( audio->WaitDone ) {
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audio->WaitDone(audio);
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}
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#ifdef __OS2__
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#ifdef DEBUG_BUILD
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printf("[SDL_RunAudio] : Task exiting. (TID%d)\n", SDL_ThreadID());
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#endif
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#endif
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return(0);
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}
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static void SDL_LockAudio_Default(SDL_AudioDevice *audio)
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{
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if ( audio->thread && (SDL_ThreadID() == audio->threadid) ) {
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return;
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}
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SDL_mutexP(audio->mixer_lock);
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}
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static void SDL_UnlockAudio_Default(SDL_AudioDevice *audio)
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{
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if ( audio->thread && (SDL_ThreadID() == audio->threadid) ) {
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return;
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}
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SDL_mutexV(audio->mixer_lock);
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}
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static Uint16 SDL_ParseAudioFormat(const char *string)
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{
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Uint16 format = 0;
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switch (*string) {
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case 'U':
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++string;
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format |= 0x0000;
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break;
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case 'S':
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++string;
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format |= 0x8000;
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break;
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default:
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return 0;
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}
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switch (SDL_atoi(string)) {
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case 8:
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string += 1;
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format |= 8;
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break;
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case 16:
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string += 2;
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format |= 16;
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if ( SDL_strcmp(string, "LSB") == 0
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#if SDL_BYTEORDER == SDL_LIL_ENDIAN
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|| SDL_strcmp(string, "SYS") == 0
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#endif
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) {
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format |= 0x0000;
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}
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if ( SDL_strcmp(string, "MSB") == 0
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#if SDL_BYTEORDER == SDL_BIG_ENDIAN
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|| SDL_strcmp(string, "SYS") == 0
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#endif
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) {
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format |= 0x1000;
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}
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break;
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default:
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return 0;
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}
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return format;
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}
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int SDL_AudioInit(const char *driver_name)
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{
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SDL_AudioDevice *audio;
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int i = 0, idx;
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/* Check to make sure we don't overwrite 'current_audio' */
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if ( current_audio != NULL ) {
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SDL_AudioQuit();
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}
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/* Select the proper audio driver */
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audio = NULL;
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idx = 0;
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#if SDL_AUDIO_DRIVER_ESD
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if ( (driver_name == NULL) && (SDL_getenv("ESPEAKER") != NULL) ) {
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/* Ahem, we know that if ESPEAKER is set, user probably wants
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to use ESD, but don't start it if it's not already running.
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This probably isn't the place to do this, but... Shh! :)
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*/
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for ( i=0; bootstrap[i]; ++i ) {
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if ( SDL_strcasecmp(bootstrap[i]->name, "esd") == 0 ) {
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#ifdef HAVE_PUTENV
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const char *esd_no_spawn;
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/* Don't start ESD if it's not running */
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esd_no_spawn = getenv("ESD_NO_SPAWN");
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if ( esd_no_spawn == NULL ) {
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putenv("ESD_NO_SPAWN=1");
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}
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#endif
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if ( bootstrap[i]->available() ) {
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audio = bootstrap[i]->create(0);
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break;
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}
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#ifdef HAVE_UNSETENV
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if ( esd_no_spawn == NULL ) {
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unsetenv("ESD_NO_SPAWN");
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}
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#endif
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}
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}
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}
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#endif /* SDL_AUDIO_DRIVER_ESD */
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if ( audio == NULL ) {
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if ( driver_name != NULL ) {
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#if 0 /* This will be replaced with a better driver selection API */
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if ( SDL_strrchr(driver_name, ':') != NULL ) {
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idx = atoi(SDL_strrchr(driver_name, ':')+1);
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}
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#endif
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for ( i=0; bootstrap[i]; ++i ) {
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if (SDL_strcasecmp(bootstrap[i]->name, driver_name) == 0) {
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if ( bootstrap[i]->available() ) {
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audio=bootstrap[i]->create(idx);
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break;
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}
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}
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}
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} else {
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for ( i=0; bootstrap[i]; ++i ) {
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if ( bootstrap[i]->available() ) {
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audio = bootstrap[i]->create(idx);
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if ( audio != NULL ) {
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break;
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}
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}
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}
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}
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if ( audio == NULL ) {
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SDL_SetError("No available audio device");
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#if 0 /* Don't fail SDL_Init() if audio isn't available.
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SDL_OpenAudio() will handle it at that point. *sigh*
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*/
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return(-1);
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#endif
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}
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}
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current_audio = audio;
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if ( current_audio ) {
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current_audio->name = bootstrap[i]->name;
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if ( !current_audio->LockAudio && !current_audio->UnlockAudio ) {
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current_audio->LockAudio = SDL_LockAudio_Default;
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current_audio->UnlockAudio = SDL_UnlockAudio_Default;
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}
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}
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return(0);
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}
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char *SDL_AudioDriverName(char *namebuf, int maxlen)
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{
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if ( current_audio != NULL ) {
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SDL_strlcpy(namebuf, current_audio->name, maxlen);
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return(namebuf);
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}
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return(NULL);
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}
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int SDL_OpenAudio(SDL_AudioSpec *desired, SDL_AudioSpec *obtained)
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{
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SDL_AudioDevice *audio;
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const char *env;
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/* Start up the audio driver, if necessary */
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if ( ! current_audio ) {
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if ( (SDL_InitSubSystem(SDL_INIT_AUDIO) < 0) ||
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(current_audio == NULL) ) {
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return(-1);
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}
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}
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audio = current_audio;
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if (audio->opened) {
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SDL_SetError("Audio device is already opened");
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return(-1);
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}
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/* Verify some parameters */
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if ( desired->freq == 0 ) {
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env = SDL_getenv("SDL_AUDIO_FREQUENCY");
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if ( env ) {
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desired->freq = SDL_atoi(env);
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}
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}
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if ( desired->freq == 0 ) {
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/* Pick some default audio frequency */
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desired->freq = 22050;
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}
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if ( desired->format == 0 ) {
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env = SDL_getenv("SDL_AUDIO_FORMAT");
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if ( env ) {
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desired->format = SDL_ParseAudioFormat(env);
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}
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}
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if ( desired->format == 0 ) {
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/* Pick some default audio format */
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desired->format = AUDIO_S16;
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}
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if ( desired->channels == 0 ) {
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env = SDL_getenv("SDL_AUDIO_CHANNELS");
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if ( env ) {
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desired->channels = (Uint8)SDL_atoi(env);
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}
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}
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if ( desired->channels == 0 ) {
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/* Pick a default number of channels */
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desired->channels = 2;
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}
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switch ( desired->channels ) {
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case 1: /* Mono */
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case 2: /* Stereo */
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case 4: /* surround */
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case 6: /* surround with center and lfe */
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break;
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default:
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SDL_SetError("1 (mono) and 2 (stereo) channels supported");
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return(-1);
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}
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if ( desired->samples == 0 ) {
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env = SDL_getenv("SDL_AUDIO_SAMPLES");
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if ( env ) {
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desired->samples = (Uint16)SDL_atoi(env);
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}
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}
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if ( desired->samples == 0 ) {
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/* Pick a default of ~46 ms at desired frequency */
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int samples = (desired->freq / 1000) * 46;
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int power2 = 1;
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while ( power2 < samples ) {
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power2 *= 2;
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}
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desired->samples = power2;
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}
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if ( desired->callback == NULL ) {
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SDL_SetError("SDL_OpenAudio() passed a NULL callback");
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return(-1);
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}
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#if SDL_THREADS_DISABLED
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/* Uses interrupt driven audio, without thread */
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#else
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/* Create a semaphore for locking the sound buffers */
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audio->mixer_lock = SDL_CreateMutex();
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if ( audio->mixer_lock == NULL ) {
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SDL_SetError("Couldn't create mixer lock");
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SDL_CloseAudio();
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return(-1);
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}
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#endif /* SDL_THREADS_DISABLED */
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/* Calculate the silence and size of the audio specification */
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SDL_CalculateAudioSpec(desired);
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/* Open the audio subsystem */
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SDL_memcpy(&audio->spec, desired, sizeof(audio->spec));
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audio->convert.needed = 0;
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audio->enabled = 1;
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audio->paused = 1;
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audio->opened = audio->OpenAudio(audio, &audio->spec)+1;
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if ( ! audio->opened ) {
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SDL_CloseAudio();
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return(-1);
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}
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/* If the audio driver changes the buffer size, accept it */
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if ( audio->spec.samples != desired->samples ) {
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desired->samples = audio->spec.samples;
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SDL_CalculateAudioSpec(desired);
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}
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/* Allocate a fake audio memory buffer */
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audio->fake_stream = SDL_AllocAudioMem(audio->spec.size);
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if ( audio->fake_stream == NULL ) {
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SDL_CloseAudio();
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SDL_OutOfMemory();
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return(-1);
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}
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/* See if we need to do any conversion */
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if ( obtained != NULL ) {
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SDL_memcpy(obtained, &audio->spec, sizeof(audio->spec));
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} else if ( desired->freq != audio->spec.freq ||
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desired->format != audio->spec.format ||
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desired->channels != audio->spec.channels ) {
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/* Build an audio conversion block */
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if ( SDL_BuildAudioCVT(&audio->convert,
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desired->format, desired->channels,
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desired->freq,
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audio->spec.format, audio->spec.channels,
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audio->spec.freq) < 0 ) {
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SDL_CloseAudio();
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return(-1);
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}
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if ( audio->convert.needed ) {
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audio->convert.len = (int) ( ((double) audio->spec.size) /
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audio->convert.len_ratio );
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audio->convert.buf =(Uint8 *)SDL_AllocAudioMem(
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audio->convert.len*audio->convert.len_mult);
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if ( audio->convert.buf == NULL ) {
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SDL_CloseAudio();
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SDL_OutOfMemory();
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return(-1);
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}
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}
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}
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/* Start the audio thread if necessary */
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switch (audio->opened) {
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case 1:
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/* Start the audio thread */
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#if (defined(__WIN32__) && !defined(_WIN32_WCE)) && !defined(HAVE_LIBC) && !defined(__SYMBIAN32__)
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|
#undef SDL_CreateThread
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|
audio->thread = SDL_CreateThread(SDL_RunAudio, audio, NULL, NULL);
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|
#else
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|
audio->thread = SDL_CreateThread(SDL_RunAudio, audio);
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|
#endif
|
|
if ( audio->thread == NULL ) {
|
|
SDL_CloseAudio();
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|
SDL_SetError("Couldn't create audio thread");
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|
return(-1);
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|
}
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|
break;
|
|
|
|
default:
|
|
/* The audio is now playing */
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|
break;
|
|
}
|
|
|
|
return(0);
|
|
}
|
|
|
|
SDL_audiostatus SDL_GetAudioStatus(void)
|
|
{
|
|
SDL_AudioDevice *audio = current_audio;
|
|
SDL_audiostatus status;
|
|
|
|
status = SDL_AUDIO_STOPPED;
|
|
if ( audio && audio->enabled ) {
|
|
if ( audio->paused ) {
|
|
status = SDL_AUDIO_PAUSED;
|
|
} else {
|
|
status = SDL_AUDIO_PLAYING;
|
|
}
|
|
}
|
|
return(status);
|
|
}
|
|
|
|
void SDL_PauseAudio (int pause_on)
|
|
{
|
|
SDL_AudioDevice *audio = current_audio;
|
|
|
|
if ( audio ) {
|
|
audio->paused = pause_on;
|
|
}
|
|
}
|
|
|
|
void SDL_LockAudio (void)
|
|
{
|
|
SDL_AudioDevice *audio = current_audio;
|
|
|
|
/* Obtain a lock on the mixing buffers */
|
|
if ( audio && audio->LockAudio ) {
|
|
audio->LockAudio(audio);
|
|
}
|
|
}
|
|
|
|
void SDL_UnlockAudio (void)
|
|
{
|
|
SDL_AudioDevice *audio = current_audio;
|
|
|
|
/* Release lock on the mixing buffers */
|
|
if ( audio && audio->UnlockAudio ) {
|
|
audio->UnlockAudio(audio);
|
|
}
|
|
}
|
|
|
|
void SDL_CloseAudio (void)
|
|
{
|
|
SDL_QuitSubSystem(SDL_INIT_AUDIO);
|
|
}
|
|
|
|
void SDL_AudioQuit(void)
|
|
{
|
|
SDL_AudioDevice *audio = current_audio;
|
|
|
|
if ( audio ) {
|
|
audio->enabled = 0;
|
|
if ( audio->thread != NULL ) {
|
|
SDL_WaitThread(audio->thread, NULL);
|
|
}
|
|
if ( audio->mixer_lock != NULL ) {
|
|
SDL_DestroyMutex(audio->mixer_lock);
|
|
}
|
|
if ( audio->fake_stream != NULL ) {
|
|
SDL_FreeAudioMem(audio->fake_stream);
|
|
}
|
|
if ( audio->convert.needed ) {
|
|
SDL_FreeAudioMem(audio->convert.buf);
|
|
|
|
}
|
|
if ( audio->opened ) {
|
|
audio->CloseAudio(audio);
|
|
audio->opened = 0;
|
|
}
|
|
/* Free the driver data */
|
|
audio->free(audio);
|
|
current_audio = NULL;
|
|
}
|
|
}
|
|
|
|
#define NUM_FORMATS 6
|
|
static int format_idx;
|
|
static int format_idx_sub;
|
|
static Uint16 format_list[NUM_FORMATS][NUM_FORMATS] = {
|
|
{ AUDIO_U8, AUDIO_S8, AUDIO_S16LSB, AUDIO_S16MSB, AUDIO_U16LSB, AUDIO_U16MSB },
|
|
{ AUDIO_S8, AUDIO_U8, AUDIO_S16LSB, AUDIO_S16MSB, AUDIO_U16LSB, AUDIO_U16MSB },
|
|
{ AUDIO_S16LSB, AUDIO_S16MSB, AUDIO_U16LSB, AUDIO_U16MSB, AUDIO_U8, AUDIO_S8 },
|
|
{ AUDIO_S16MSB, AUDIO_S16LSB, AUDIO_U16MSB, AUDIO_U16LSB, AUDIO_U8, AUDIO_S8 },
|
|
{ AUDIO_U16LSB, AUDIO_U16MSB, AUDIO_S16LSB, AUDIO_S16MSB, AUDIO_U8, AUDIO_S8 },
|
|
{ AUDIO_U16MSB, AUDIO_U16LSB, AUDIO_S16MSB, AUDIO_S16LSB, AUDIO_U8, AUDIO_S8 },
|
|
};
|
|
|
|
Uint16 SDL_FirstAudioFormat(Uint16 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());
|
|
}
|
|
|
|
Uint16 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 = (spec->format&0xFF)/8;
|
|
spec->size *= spec->channels;
|
|
spec->size *= spec->samples;
|
|
}
|
|
|
|
void SDL_Audio_SetCaption(const char *caption)
|
|
{
|
|
if ((current_audio) && (current_audio->SetCaption)) {
|
|
current_audio->SetCaption(current_audio, caption);
|
|
}
|
|
}
|
|
|