/*

* SDL_sound -- An abstract sound format decoding API.

* Copyright (C) 2001 Ryan C. Gordon.

*

* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA

*/

/*

* WAV decoder for SDL_sound.

*

* This driver handles Microsoft .WAVs, in as many of the thousands of

* variations as we can.

*

* Please see the file COPYING in the source's root directory.

*

* This file written by Ryan C. Gordon. (icculus@icculus.org)

*/

#if HAVE_CONFIG_H

# include <config.h>

#endif

#ifdef SOUND_SUPPORTS_WAV

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include "SDL_sound.h"

#define __SDL_SOUND_INTERNAL__

#include "SDL_sound_internal.h"

static int WAV_init(void);

static void WAV_quit(void);

static int WAV_open(Sound_Sample *sample, const char *ext);

static void WAV_close(Sound_Sample *sample);

static Uint32 WAV_read(Sound_Sample *sample);

static int WAV_rewind(Sound_Sample *sample);

static int WAV_seek(Sound_Sample *sample, Uint32 ms);

static const char *extensions_wav[] = { "WAV", NULL };

const Sound_DecoderFunctions __Sound_DecoderFunctions_WAV =

{

{

extensions_wav,

"Microsoft WAVE audio format",

"Ryan C. Gordon <icculus@icculus.org>",

"http://www.icculus.org/SDL_sound/"

},

WAV_init, /* init() method */

WAV_quit, /* quit() method */

WAV_open, /* open() method */

WAV_close, /* close() method */

WAV_read, /* read() method */

WAV_rewind, /* rewind() method */

WAV_seek /* seek() method */

};

/* Better than SDL_ReadLE16, since you can detect i/o errors... */

static __inline__ int read_le16(SDL_RWops *rw, Uint16 *ui16)

{

int rc = SDL_RWread(rw, ui16, sizeof (Uint16), 1);

BAIL_IF_MACRO(rc != 1, ERR_IO_ERROR, 0);

*ui16 = SDL_SwapLE16(*ui16);

return(1);

} /* read_le16 */

/* Better than SDL_ReadLE32, since you can detect i/o errors... */

static __inline__ int read_le32(SDL_RWops *rw, Uint32 *ui32)

{

int rc = SDL_RWread(rw, ui32, sizeof (Uint32), 1);

BAIL_IF_MACRO(rc != 1, ERR_IO_ERROR, 0);

*ui32 = SDL_SwapLE32(*ui32);

return(1);

} /* read_le32 */

/* This is just cleaner on the caller's end... */

static __inline__ int read_uint8(SDL_RWops *rw, Uint8 *ui8)

{

int rc = SDL_RWread(rw, ui8, sizeof (Uint8), 1);

BAIL_IF_MACRO(rc != 1, ERR_IO_ERROR, 0);

return(1);

} /* read_uint8 */

/* Chunk management code... */

#define riffID 0x46464952 /* "RIFF", in ascii. */

#define waveID 0x45564157 /* "WAVE", in ascii. */

#define factID 0x74636166 /* "fact", in ascii. */

/*****************************************************************************

* The FORMAT chunk... *

*****************************************************************************/

#define fmtID 0x20746D66 /* "fmt ", in ascii. */

#define FMT_NORMAL 0x0001 /* Uncompressed waveform data. */

#define FMT_ADPCM 0x0002 /* ADPCM compressed waveform data. */

typedef struct

{

Sint16 iCoef1;

Sint16 iCoef2;

} ADPCMCOEFSET;

typedef struct

{

Uint8 bPredictor;

Uint16 iDelta;

Sint16 iSamp1;

Sint16 iSamp2;

} ADPCMBLOCKHEADER;

typedef struct S_WAV_FMT_T

} fmt_t;

/*

* Read in a fmt_t from disk. This makes this process safe regardless of

* the processor's byte order or how the fmt_t structure is packed.

* Note that the union "fmt" is not read in here; that is handled as

* needed in the read_fmt_* functions.

*/

static int read_fmt_chunk(SDL_RWops *rw, fmt_t *fmt)

{

/* skip reading the chunk ID, since it was already read at this point... */

fmt->chunkID = fmtID;

BAIL_IF_MACRO(!read_le32(rw, &fmt->chunkSize), NULL, 0);

BAIL_IF_MACRO(fmt->chunkSize < 16, "WAV: Invalid chunk size", 0);

fmt->next_chunk_offset = SDL_RWtell(rw) + fmt->chunkSize;

BAIL_IF_MACRO(!read_le16(rw, &fmt->wFormatTag), NULL, 0);

BAIL_IF_MACRO(!read_le16(rw, &fmt->wChannels), NULL, 0);

BAIL_IF_MACRO(!read_le32(rw, &fmt->dwSamplesPerSec), NULL, 0);

BAIL_IF_MACRO(!read_le32(rw, &fmt->dwAvgBytesPerSec), NULL, 0);

BAIL_IF_MACRO(!read_le16(rw, &fmt->wBlockAlign), NULL, 0);

BAIL_IF_MACRO(!read_le16(rw, &fmt->wBitsPerSample), NULL, 0);

return(1);

} /* read_fmt_chunk */

/*****************************************************************************

* The DATA chunk... *

*****************************************************************************/

#define dataID 0x61746164 /* "data", in ascii. */

typedef struct

{

Uint32 chunkID;

Sint32 chunkSize;

/* Then, (chunkSize) bytes of waveform data... */

} data_t;

/*

* Read in a data_t from disk. This makes this process safe regardless of

* the processor's byte order or how the fmt_t structure is packed.

*/

static int read_data_chunk(SDL_RWops *rw, data_t *data)

{

/* skip reading the chunk ID, since it was already read at this point... */

data->chunkID = dataID;

BAIL_IF_MACRO(!read_le32(rw, &data->chunkSize), NULL, 0);

return(1);

} /* read_data_chunk */

/*****************************************************************************

* this is what we store in our internal->decoder_private field... *

*****************************************************************************/

typedef struct

{

fmt_t *fmt;

Sint32 bytesLeft;

} wav_t;

/*****************************************************************************

* Normal, uncompressed waveform handler... *

*****************************************************************************/

/*

* Sound_Decode() lands here for uncompressed WAVs...

*/

static Uint32 read_sample_fmt_normal(Sound_Sample *sample)

{

Uint32 retval;

Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;

wav_t *w = (wav_t *) internal->decoder_private;

Uint32 max = (internal->buffer_size < (Uint32) w->bytesLeft) ?

internal->buffer_size : (Uint32) w->bytesLeft;

assert(max > 0);

/*

* We don't actually do any decoding, so we read the wav data

* directly into the internal buffer...

*/

retval = SDL_RWread(internal->rw, internal->buffer, 1, max);

w->bytesLeft -= retval;

/* Make sure the read went smoothly... */

if ((retval == 0) || (w->bytesLeft == 0))

sample->flags |= SOUND_SAMPLEFLAG_EOF;

else if (retval == -1)

sample->flags |= SOUND_SAMPLEFLAG_ERROR;

/* (next call this EAGAIN may turn into an EOF or error.) */

else if (retval < internal->buffer_size)

sample->flags |= SOUND_SAMPLEFLAG_EAGAIN;

return(retval);

} /* read_sample_fmt_normal */

static int seek_sample_fmt_normal(Sound_Sample *sample, Uint32 ms)

{

Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;

wav_t *w = (wav_t *) internal->decoder_private;

fmt_t *fmt = w->fmt;

int offset = __Sound_convertMsToBytePos(&sample->actual, ms);

int pos = (int) (fmt->data_starting_offset + offset);

int rc = SDL_RWseek(internal->rw, pos, SEEK_SET);

BAIL_IF_MACRO(rc != pos, ERR_IO_ERROR, 0);

w->bytesLeft = fmt->total_bytes - offset;

return(1); /* success. */

} /* seek_sample_fmt_normal */

static int rewind_sample_fmt_normal(Sound_Sample *sample)

{

/* no-op. */

return(1);

} /* rewind_sample_fmt_normal */

static int read_fmt_normal(SDL_RWops *rw, fmt_t *fmt)

{

/* (don't need to read more from the RWops...) */

fmt->free = NULL;

fmt->read_sample = read_sample_fmt_normal;

fmt->rewind_sample = rewind_sample_fmt_normal;

fmt->seek_sample = seek_sample_fmt_normal;

return(1);

} /* read_fmt_normal */

/*****************************************************************************

* ADPCM compression handler... *

*****************************************************************************/

#define FIXED_POINT_COEF_BASE 256

#define FIXED_POINT_ADAPTION_BASE 256

#define SMALLEST_ADPCM_DELTA 16

static __inline__ int read_adpcm_block_headers(Sound_Sample *sample)

{

Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;

SDL_RWops *rw = internal->rw;

wav_t *w = (wav_t *) internal->decoder_private;

fmt_t *fmt = w->fmt;

ADPCMBLOCKHEADER *headers = fmt->fmt.adpcm.blockheaders;

int i;

int max = fmt->wChannels;

if (w->bytesLeft < fmt->wBlockAlign)

{

sample->flags |= SOUND_SAMPLEFLAG_EOF;

return(0);

} /* if */

w->bytesLeft -= fmt->wBlockAlign;

for (i = 0; i < max; i++)

BAIL_IF_MACRO(!read_uint8(rw, &headers[i].bPredictor), NULL, 0);

for (i = 0; i < max; i++)

BAIL_IF_MACRO(!read_le16(rw, &headers[i].iDelta), NULL, 0);

for (i = 0; i < max; i++)

BAIL_IF_MACRO(!read_le16(rw, &headers[i].iSamp1), NULL, 0);

for (i = 0; i < max; i++)

BAIL_IF_MACRO(!read_le16(rw, &headers[i].iSamp2), NULL, 0);

fmt->fmt.adpcm.samples_left_in_block = fmt->fmt.adpcm.wSamplesPerBlock;

fmt->fmt.adpcm.nibble_state = 0;

return(1);

} /* read_adpcm_block_headers */

static __inline__ void do_adpcm_nibble(Uint8 nib,

ADPCMBLOCKHEADER *header,

Sint32 lPredSamp)

{

static const Sint32 max_audioval = ((1<<(16-1))-1);

static const Sint32 min_audioval = -(1<<(16-1));

static const Sint32 AdaptionTable[] =

{

230, 230, 230, 230, 307, 409, 512, 614,

768, 614, 512, 409, 307, 230, 230, 230

};

Sint32 lNewSamp;

Sint32 delta;

if (nib & 0x08)

lNewSamp = lPredSamp + (header->iDelta * (nib - 0x10));

else

lNewSamp = lPredSamp + (header->iDelta * nib);

/* clamp value... */

if (lNewSamp < min_audioval)

lNewSamp = min_audioval;

else if (lNewSamp > max_audioval)

lNewSamp = max_audioval;

delta = ((Sint32) header->iDelta * AdaptionTable[nib]) /

FIXED_POINT_ADAPTION_BASE;

if (delta < SMALLEST_ADPCM_DELTA)

delta = SMALLEST_ADPCM_DELTA;

header->iDelta = delta;

header->iSamp2 = header->iSamp1;

header->iSamp1 = lNewSamp;

} /* do_adpcm_nibble */

static __inline__ int decode_adpcm_sample_frame(Sound_Sample *sample)

{

Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;

wav_t *w = (wav_t *) internal->decoder_private;

fmt_t *fmt = w->fmt;

ADPCMBLOCKHEADER *headers = fmt->fmt.adpcm.blockheaders;

SDL_RWops *rw = internal->rw;

int i;

int max = fmt->wChannels;

Sint32 delta;

Uint8 nib = fmt->fmt.adpcm.nibble;

for (i = 0; i < max; i++)

{

Uint8 byte;

Sint16 iCoef1 = fmt->fmt.adpcm.aCoef[headers[i].bPredictor].iCoef1;

Sint16 iCoef2 = fmt->fmt.adpcm.aCoef[headers[i].bPredictor].iCoef2;

Sint32 lPredSamp = ((headers[i].iSamp1 * iCoef1) +

(headers[i].iSamp2 * iCoef2)) /

FIXED_POINT_COEF_BASE;

if (fmt->fmt.adpcm.nibble_state == 0)

{

BAIL_IF_MACRO(!read_uint8(rw, &nib), NULL, 0);

fmt->fmt.adpcm.nibble_state = 1;

do_adpcm_nibble(nib >> 4, &headers[i], lPredSamp);

} /* if */

else

{

fmt->fmt.adpcm.nibble_state = 0;

do_adpcm_nibble(nib & 0x0F, &headers[i], lPredSamp);

} /* else */

} /* for */

fmt->fmt.adpcm.nibble = nib;

return(1);

} /* decode_adpcm_sample_frame */

static __inline__ void put_adpcm_sample_frame1(void *_buf, fmt_t *fmt)

{

Uint16 *buf = (Uint16 *) _buf;

ADPCMBLOCKHEADER *headers = fmt->fmt.adpcm.blockheaders;

int i;

for (i = 0; i < fmt->wChannels; i++)

*(buf++) = headers[i].iSamp1;

} /* put_adpcm_sample_frame1 */

static __inline__ void put_adpcm_sample_frame2(void *_buf, fmt_t *fmt)

{

Uint16 *buf = (Uint16 *) _buf;

ADPCMBLOCKHEADER *headers = fmt->fmt.adpcm.blockheaders;

int i;

for (i = 0; i < fmt->wChannels; i++)

*(buf++) = headers[i].iSamp2;

} /* put_adpcm_sample_frame2 */

/*

* Sound_Decode() lands here for ADPCM-encoded WAVs...

*/

static Uint32 read_sample_fmt_adpcm(Sound_Sample *sample)

{

Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;

wav_t *w = (wav_t *) internal->decoder_private;

fmt_t *fmt = w->fmt;

Uint32 bw = 0;

while (bw < internal->buffer_size)

{

/* write ongoing sample frame before reading more data... */

switch (fmt->fmt.adpcm.samples_left_in_block)

{

case 0: /* need to read a new block... */

if (!read_adpcm_block_headers(sample))

{

if ((sample->flags & SOUND_SAMPLEFLAG_EOF) == 0)

sample->flags |= SOUND_SAMPLEFLAG_ERROR;

return(bw);

} /* if */

/* only write first sample frame for now. */

put_adpcm_sample_frame2((Uint8 *) internal->buffer + bw, fmt);

fmt->fmt.adpcm.samples_left_in_block--;

bw += fmt->sample_frame_size;

break;

case 1: /* output last sample frame of block... */

put_adpcm_sample_frame1((Uint8 *) internal->buffer + bw, fmt);

fmt->fmt.adpcm.samples_left_in_block--;

bw += fmt->sample_frame_size;

break;

default: /* output latest sample frame and read a new one... */

put_adpcm_sample_frame1((Uint8 *) internal->buffer + bw, fmt);

fmt->fmt.adpcm.samples_left_in_block--;

bw += fmt->sample_frame_size;

if (!decode_adpcm_sample_frame(sample))

{

sample->flags |= SOUND_SAMPLEFLAG_ERROR;

return(bw);

} /* if */

} /* switch */

} /* while */

return(bw);

} /* read_sample_fmt_adpcm */

/*

* Sound_FreeSample() lands here for ADPCM-encoded WAVs...

*/

static void free_fmt_adpcm(fmt_t *fmt)

{

if (fmt->fmt.adpcm.aCoef != NULL)

free(fmt->fmt.adpcm.aCoef);

if (fmt->fmt.adpcm.blockheaders != NULL)

free(fmt->fmt.adpcm.blockheaders);

} /* free_fmt_adpcm */

static int rewind_sample_fmt_adpcm(Sound_Sample *sample)

{

Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;

wav_t *w = (wav_t *) internal->decoder_private;

w->fmt->fmt.adpcm.samples_left_in_block = 0;

return(1);

} /* rewind_sample_fmt_adpcm */

static int seek_sample_fmt_adpcm(Sound_Sample *sample, Uint32 ms)

{

Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;

wav_t *w = (wav_t *) internal->decoder_private;

fmt_t *fmt = w->fmt;

Uint32 origsampsleft = fmt->fmt.adpcm.samples_left_in_block;

int origpos = SDL_RWtell(internal->rw);

int offset = __Sound_convertMsToBytePos(&sample->actual, ms);

int bpb = (fmt->fmt.adpcm.wSamplesPerBlock * fmt->sample_frame_size);

int skipsize = (offset / bpb) * fmt->wBlockAlign;

int pos = skipsize + fmt->data_starting_offset;

int rc = SDL_RWseek(internal->rw, pos, SEEK_SET);

BAIL_IF_MACRO(rc != pos, ERR_IO_ERROR, 0);

/* The offset we need is in this block, so we need to decode to there. */

skipsize += (offset % bpb);

rc = (offset % bpb); /* bytes into this block we need to decode */

if (!read_adpcm_block_headers(sample))

{

SDL_RWseek(internal->rw, origpos, SEEK_SET); /* try to make sane. */

return(0);

} /* if */

/* first sample frame of block is a freebie. :) */

fmt->fmt.adpcm.samples_left_in_block--;

rc -= fmt->sample_frame_size;

while (rc > 0)

{

if (!decode_adpcm_sample_frame(sample))

{

SDL_RWseek(internal->rw, origpos, SEEK_SET);

fmt->fmt.adpcm.samples_left_in_block = origsampsleft;

return(0);

} /* if */

fmt->fmt.adpcm.samples_left_in_block--;

rc -= fmt->sample_frame_size;

} /* while */

w->bytesLeft = fmt->total_bytes - skipsize;

return(1); /* success. */

} /* seek_sample_fmt_adpcm */

/*

* Read in the adpcm-specific info from disk. This makes this process

* safe regardless of the processor's byte order or how the fmt_t

* structure is packed.

*/

static int read_fmt_adpcm(SDL_RWops *rw, fmt_t *fmt)

{

size_t i;

memset(&fmt->fmt.adpcm, '\0', sizeof (fmt->fmt.adpcm));

fmt->free = free_fmt_adpcm;

fmt->read_sample = read_sample_fmt_adpcm;

fmt->rewind_sample = rewind_sample_fmt_adpcm;

fmt->seek_sample = seek_sample_fmt_adpcm;

BAIL_IF_MACRO(!read_le16(rw, &fmt->fmt.adpcm.cbSize), NULL, 0);

BAIL_IF_MACRO(!read_le16(rw, &fmt->fmt.adpcm.wSamplesPerBlock), NULL, 0);

BAIL_IF_MACRO(!read_le16(rw, &fmt->fmt.adpcm.wNumCoef), NULL, 0);

/* fmt->free() is always called, so these malloc()s will be cleaned up. */

i = sizeof (ADPCMCOEFSET) * fmt->fmt.adpcm.wNumCoef;

fmt->fmt.adpcm.aCoef = (ADPCMCOEFSET *) malloc(i);

BAIL_IF_MACRO(fmt->fmt.adpcm.aCoef == NULL, ERR_OUT_OF_MEMORY, 0);

for (i = 0; i < fmt->fmt.adpcm.wNumCoef; i++)

{

BAIL_IF_MACRO(!read_le16(rw, &fmt->fmt.adpcm.aCoef[i].iCoef1), NULL, 0);

BAIL_IF_MACRO(!read_le16(rw, &fmt->fmt.adpcm.aCoef[i].iCoef2), NULL, 0);

} /* for */

i = sizeof (ADPCMBLOCKHEADER) * fmt->wChannels;

fmt->fmt.adpcm.blockheaders = (ADPCMBLOCKHEADER *) malloc(i);

BAIL_IF_MACRO(fmt->fmt.adpcm.blockheaders == NULL, ERR_OUT_OF_MEMORY, 0);

return(1);

} /* read_fmt_adpcm */

/*****************************************************************************

* Everything else... *

*****************************************************************************/

static int WAV_init(void)

{

return(1); /* always succeeds. */

} /* WAV_init */

static void WAV_quit(void)

{

/* it's a no-op. */

} /* WAV_quit */

static int read_fmt(SDL_RWops *rw, fmt_t *fmt)

{

/* if it's in this switch statement, we support the format. */

switch (fmt->wFormatTag)

{

case FMT_NORMAL:

SNDDBG(("WAV: Appears to be uncompressed audio.\n"));

return(read_fmt_normal(rw, fmt));

case FMT_ADPCM:

SNDDBG(("WAV: Appears to be ADPCM compressed audio.\n"));

return(read_fmt_adpcm(rw, fmt));

/* add other types here. */

default:

SNDDBG(("WAV: Format 0x%X is unknown.\n",

(unsigned int) fmt->wFormatTag));

BAIL_MACRO("WAV: Unsupported format", 0);

} /* switch */

assert(0); /* shouldn't hit this point. */

return(0);

} /* read_fmt */

/*

* Locate a specific chunk in the WAVE file by ID...

*/

static int find_chunk(SDL_RWops *rw, Uint32 id)

{

Sint32 siz = 0;

Uint32 _id = 0;

Uint32 pos = SDL_RWtell(rw);

while (1)

{

BAIL_IF_MACRO(!read_le32(rw, &_id), NULL, 0);

if (_id == id)

return(1);

/* skip ahead and see what next chunk is... */

BAIL_IF_MACRO(!read_le32(rw, &siz), NULL, 0);

assert(siz >= 0);

pos += (sizeof (Uint32) * 2) + siz;

if (siz > 0)

BAIL_IF_MACRO(SDL_RWseek(rw, pos, SEEK_SET) != pos, NULL, 0);

} /* while */

return(0); /* shouldn't hit this, but just in case... */

} /* find_chunk */

static int WAV_open_internal(Sound_Sample *sample, const char *ext, fmt_t *fmt)

{

Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;

SDL_RWops *rw = internal->rw;

data_t d;

wav_t *w;

Uint32 pos;

BAIL_IF_MACRO(SDL_ReadLE32(rw) != riffID, "WAV: Not a RIFF file.", 0);

SDL_ReadLE32(rw); /* throw the length away; we get this info later. */

BAIL_IF_MACRO(SDL_ReadLE32(rw) != waveID, "WAV: Not a WAVE file.", 0);

BAIL_IF_MACRO(!find_chunk(rw, fmtID), "WAV: No format chunk.", 0);

BAIL_IF_MACRO(!read_fmt_chunk(rw, fmt), "WAV: Can't read format chunk.", 0);

sample->actual.channels = (Uint8) fmt->wChannels;

sample->actual.rate = fmt->dwSamplesPerSec;

if ((fmt->wBitsPerSample == 4) /*|| (fmt->wBitsPerSample == 0) */ )

sample->actual.format = AUDIO_S16SYS;

else if (fmt->wBitsPerSample == 8)

sample->actual.format = AUDIO_U8;

else if (fmt->wBitsPerSample == 16)

sample->actual.format = AUDIO_S16LSB;

else

{

SNDDBG(("WAV: %d bits per sample!?\n", (int) fmt->wBitsPerSample));

BAIL_MACRO("WAV: Unsupported sample size.", 0);

} /* else */

BAIL_IF_MACRO(!read_fmt(rw, fmt), NULL, 0);

SDL_RWseek(rw, fmt->next_chunk_offset, SEEK_SET);

BAIL_IF_MACRO(!find_chunk(rw, dataID), "WAV: No data chunk.", 0);

BAIL_IF_MACRO(!read_data_chunk(rw, &d), "WAV: Can't read data chunk.", 0);

w = (wav_t *) malloc(sizeof(wav_t));

BAIL_IF_MACRO(w == NULL, ERR_OUT_OF_MEMORY, 0);

w->fmt = fmt;

fmt->total_bytes = w->bytesLeft = d.chunkSize;

fmt->data_starting_offset = SDL_RWtell(rw);

fmt->sample_frame_size = ( ((sample->actual.format & 0xFF) / 8) *

sample->actual.channels );

internal->decoder_private = (void *) w;

internal->total_time = (fmt->total_bytes / fmt->dwAvgBytesPerSec) * 1000;

internal->total_time += (fmt->total_bytes % fmt->dwAvgBytesPerSec)

* 1000 / fmt->dwAvgBytesPerSec;

sample->flags = SOUND_SAMPLEFLAG_NONE;

if (fmt->seek_sample != NULL)

sample->flags |= SOUND_SAMPLEFLAG_CANSEEK;

SNDDBG(("WAV: Accepting data stream.\n"));

return(1); /* we'll handle this data. */

} /* WAV_open_internal */

static int WAV_open(Sound_Sample *sample, const char *ext)

{

int rc;

fmt_t *fmt = (fmt_t *) malloc(sizeof (fmt_t));

BAIL_IF_MACRO(fmt == NULL, ERR_OUT_OF_MEMORY, 0);

memset(fmt, '\0', sizeof (fmt_t));

rc = WAV_open_internal(sample, ext, fmt);

if (!rc)

{

if (fmt->free != NULL)

fmt->free(fmt);

free(fmt);

} /* if */

return(rc);

} /* WAV_open */

static void WAV_close(Sound_Sample *sample)

{

Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;

wav_t *w = (wav_t *) internal->decoder_private;

if (w->fmt->free != NULL)

w->fmt->free(w->fmt);

free(w->fmt);

free(w);

} /* WAV_close */

static Uint32 WAV_read(Sound_Sample *sample)

{

Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;

wav_t *w = (wav_t *) internal->decoder_private;

return(w->fmt->read_sample(sample));

} /* WAV_read */

static int WAV_rewind(Sound_Sample *sample)

{

Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;

wav_t *w = (wav_t *) internal->decoder_private;

fmt_t *fmt = w->fmt;

int rc = SDL_RWseek(internal->rw, fmt->data_starting_offset, SEEK_SET);

BAIL_IF_MACRO(rc != fmt->data_starting_offset, ERR_IO_ERROR, 0);

w->bytesLeft = fmt->total_bytes;

return(fmt->rewind_sample(sample));

} /* WAV_rewind */

static int WAV_seek(Sound_Sample *sample, Uint32 ms)

{

Sound_SampleInternal *internal = (Sound_SampleInternal *) sample->opaque;

wav_t *w = (wav_t *) internal->decoder_private;

return(w->fmt->seek_sample(sample, ms));

} /* WAV_seek */

#endif /* SOUND_SUPPORTS_WAV */

/* end of wav.c ... */