raze-gles/polymer/eduke32/source/jaudiolib/dsl.c

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/*
Copyright (C) 2003-2004 Ryan C. Gordon. and James Bentler
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
Originally written by Ryan C. Gordon. (icculus@clutteredmind.org)
Adapted to work with JonoF's port by James Bentler (bentler@cs.umn.edu)
*/
#include <stdlib.h>
#include <string.h>
#include "compat.h"
#include "dsl.h"
#include "pragmas.h"
#define _NEED_SDLMIXER 1
#include "sdl_inc.h"
extern int32_t MV_MixPage;
int32_t DSL_ErrorCode = DSL_Ok;
static int32_t mixer_initialized;
static int32_t interrupts_disabled = 0;
static int32_t(*_DSL_CallBackFunc)(int32_t);
static volatile char *_DSL_BufferStart;
static int32_t _DSL_BufferSize;
static int32_t _DSL_SampleRate;
static int32_t _DSL_remainder;
static Uint16 _DSL_format;
static int32_t _DSL_channels;
static Mix_Chunk *blank;
static uint8_t *blank_buf;
/*
possible todo ideas: cache sdl/sdl mixer error messages.
*/
char *DSL_ErrorString(int32_t ErrorNumber)
{
char *ErrorString;
switch (ErrorNumber)
{
case DSL_Warning:
case DSL_Error:
ErrorString = DSL_ErrorString(DSL_ErrorCode);
break;
case DSL_Ok:
ErrorString = "SDL Driver ok.";
break;
case DSL_SDLInitFailure:
ErrorString = "SDL Audio initialization failed.";
break;
case DSL_MixerActive:
ErrorString = "SDL Mixer already initialized.";
break;
case DSL_MixerInitFailure:
ErrorString = "SDL Mixer initialization failed.";
break;
default:
ErrorString = "Unknown SDL Driver error.";
break;
}
return ErrorString;
}
static void DSL_SetErrorCode(int32_t ErrorCode)
{
DSL_ErrorCode = ErrorCode;
}
int32_t DSL_Init(int32_t soundcard, int32_t mixrate, int32_t numchannels, int32_t samplebits, int32_t buffersize)
{
/* FIXME: Do I need an SDL_mixer version check
* like that in sdlmusic.h here, too???
*/
UNREFERENCED_PARAMETER(soundcard);
UNREFERENCED_PARAMETER(buffersize);
DSL_SetErrorCode(DSL_Ok);
if (SDL_InitSubSystem(SDL_INIT_AUDIO) < 0)
{
DSL_SetErrorCode(DSL_SDLInitFailure);
return DSL_Error;
}
_DSL_channels = numchannels;
_DSL_SampleRate = mixrate;
_DSL_format = (samplebits == 16) ? AUDIO_S16SYS : AUDIO_U8;
return DSL_Ok;
}
void DSL_Shutdown(void)
{
DSL_StopPlayback();
}
static void mixer_callback(int32_t chan, void *stream, int32_t len, void *udata)
{
Uint8 *stptr;
Uint8 *fxptr;
int32_t copysize;
UNREFERENCED_PARAMETER(chan);
UNREFERENCED_PARAMETER(udata);
/* len should equal _DSL_BufferSize, else this is screwed up */
stptr = (Uint8 *)stream;
if (_DSL_remainder > 0)
{
copysize = min(len, _DSL_remainder);
fxptr = (Uint8 *)(&_DSL_BufferStart[MV_MixPage *
_DSL_BufferSize]);
Bmemcpy(stptr, fxptr+(_DSL_BufferSize-_DSL_remainder), copysize);
len -= copysize;
_DSL_remainder -= copysize;
stptr += copysize;
}
while (len > 0)
{
/* new buffer */
_DSL_CallBackFunc(0);
fxptr = (Uint8 *)(&_DSL_BufferStart[MV_MixPage *
_DSL_BufferSize]);
copysize = min(len, _DSL_BufferSize);
Bmemcpy(stptr, fxptr, copysize);
len -= copysize;
stptr += copysize;
}
_DSL_remainder = len;
}
//int32_t DSL_BeginBufferedPlayback(char *BufferStart,
// int32_t BufferSize, int32_t NumDivisions, uint32_t SampleRate,
// int32_t MixMode, void(*CallBackFunc)(void))
int32_t DSL_BeginBufferedPlayback(char *BufferStart, int32_t(*CallBackFunc)(int32_t), int32_t BufferSize, int32_t NumDivisions)
{
int32_t chunksize;
if (mixer_initialized)
{
DSL_SetErrorCode(DSL_MixerActive);
return DSL_Error;
}
_DSL_CallBackFunc = CallBackFunc;
_DSL_BufferStart = BufferStart;
_DSL_BufferSize = (BufferSize / NumDivisions);
_DSL_remainder = 0;
/*
23ms is typically ideal (11025,22050,44100)
46ms isn't bad
*/
chunksize = 512;
if (_DSL_SampleRate >= 16000) chunksize *= 2;
if (_DSL_SampleRate >= 32000) chunksize *= 2;
if (Mix_OpenAudio(_DSL_SampleRate, _DSL_format, _DSL_channels, chunksize) < 0)
{
DSL_SetErrorCode(DSL_MixerInitFailure);
return DSL_Error;
}
/*
Mix_SetPostMix(mixer_callback, NULL);
*/
/* have to use a channel because postmix will overwrite the music... */
Mix_RegisterEffect(0, mixer_callback, NULL, NULL);
/* create a dummy sample just to allocate that channel */
blank_buf = (Uint8 *)malloc(4096);
memset(blank_buf, 0, 4096);
blank = Mix_QuickLoad_RAW(blank_buf, 4096);
Mix_PlayChannel(0, blank, -1);
mixer_initialized = 1;
return DSL_Ok;
}
void DSL_StopPlayback(void)
{
if (mixer_initialized)
{
Mix_HaltChannel(0);
}
if (blank != NULL)
{
Mix_FreeChunk(blank);
}
blank = NULL;
if (blank_buf != NULL)
{
free(blank_buf);
}
blank_buf = NULL;
if (mixer_initialized)
{
Mix_CloseAudio();
}
mixer_initialized = 0;
}
uint32_t DSL_GetPlaybackRate(void)
{
return _DSL_SampleRate;
}
int32_t DisableInterrupts(void)
{
if (interrupts_disabled++)
return 0;
// interrupts_disabled = 1;
SDL_LockAudio();
return(0);
}
int32_t RestoreInterrupts(int32_t flags)
{
UNREFERENCED_PARAMETER(flags);
if (--interrupts_disabled)
return 0;
// interrupts_disabled = 0;
SDL_UnlockAudio();
return(0);
}