/** * SDL_sound; An abstract sound format decoding API. * * Please see the file LICENSE.txt in the source's root directory. * * This file written by Ryan C. Gordon. */ /* * WAV decoder for SDL_sound. * * This driver handles Microsoft .WAVs, in as many of the thousands of * variations as we can. */ #define __SDL_SOUND_INTERNAL__ #include "SDL_sound_internal.h" #if SOUND_SUPPORTS_WAV /* Better than SDL_ReadLE16, since you can detect i/o errors... */ static SDL_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 SDL_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 */ static SDL_INLINE int read_le16s(SDL_RWops *rw, Sint16 *si16) { return read_le16(rw, (Uint16 *) si16); } /* read_le16s */ static SDL_INLINE int read_le32s(SDL_RWops *rw, Sint32 *si32) { return read_le32(rw, (Uint32 *) si32); } /* read_le32s */ /* This is just cleaner on the caller's end... */ static SDL_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. */ #define FMT_IEEE_FLOAT 0x0003 /* Uncompressed IEEE floating point waveform data. */ #define FMT_EXTENSIBLE 0xFFFE /* "Extensible" tag */ typedef struct { Sint16 iCoef1; Sint16 iCoef2; } ADPCMCOEFSET; typedef struct { Uint8 bPredictor; Uint16 iDelta; Sint16 iSamp1; Sint16 iSamp2; } ADPCMBLOCKHEADER; typedef struct S_WAV_FMT_T { Uint32 chunkID; Sint32 chunkSize; Uint16 wFormatTag; Uint16 wChannels; Uint32 dwSamplesPerSec; Uint32 dwAvgBytesPerSec; Uint16 wBlockAlign; Uint16 wBitsPerSample; Sint64 next_chunk_offset; Uint32 sample_frame_size; Sint64 data_starting_offset; Uint32 total_bytes; void (*free)(struct S_WAV_FMT_T *fmt); Uint32 (*read_sample)(Sound_Sample *sample); int (*rewind_sample)(Sound_Sample *sample); int (*seek_sample)(Sound_Sample *sample, Uint32 ms); union { struct { Uint16 cbSize; Uint16 wSamplesPerBlock; Uint16 wNumCoef; ADPCMCOEFSET *aCoef; ADPCMBLOCKHEADER *blockheaders; Uint32 samples_left_in_block; int nibble_state; Sint8 nibble; } adpcm; /* put other format-specific data here... */ } fmt; } 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_le32s(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_le32s(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; /* We need to convert 24-bit PCM to an SDL-friendly AUDIO_S32SYS ... */ if (w->fmt->wBitsPerSample == 24) { const Uint32 num_samples = max / 3; /* we're going to expand by 25%...3 bytes to 4. Make sure the buffer has room to expand. */ max = (num_samples - (num_samples / 4)) * 3; if (max == 0) { sample->flags |= SOUND_SAMPLEFLAG_EOF; return 0; } } SDL_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) /** FIXME: this error check is broken **/ 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; /* deal with 24-bit PCM. */ if ((retval > 0) && (w->fmt->wBitsPerSample == 24)) { const Uint32 total = retval / 3; const Uint8 *src = ((Uint8 *)internal->buffer + retval) - 3; Uint32 *dst = (Uint32 *) (((Uint8 *)internal->buffer + (total * 4)) - 4); Uint32 i; for (i = 0; i < total; i++, dst--, src -= 3) { const Uint32 sample = ((Uint32) src[0]) | (((Uint32) src[1]) << 8) | (((Uint32) src[2]) << 16); *dst = sample << 8; /* shift it up so the most significant bits cover the 32-bit space. */ } retval = total * 4; } 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; const Sint64 offset = __Sound_convertMsToBytePos(&sample->actual, ms); const Sint64 pos = (fmt->data_starting_offset + offset); const Sint64 rc = SDL_RWseek(internal->rw, pos, RW_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 SDL_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_le16s(rw, &headers[i].iSamp1), NULL, 0); for (i = 0; i < max; i++) BAIL_IF_MACRO(!read_le16s(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 SDL_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 SDL_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; Uint8 nib = fmt->fmt.adpcm.nibble; for (i = 0; i < max; i++) { 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 SDL_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 SDL_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) SDL_free(fmt->fmt.adpcm.aCoef); if (fmt->fmt.adpcm.blockheaders != NULL) SDL_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; const Uint32 origsampsleft = fmt->fmt.adpcm.samples_left_in_block; const Sint64 origpos = SDL_RWtell(internal->rw); const Sint64 offset = __Sound_convertMsToBytePos(&sample->actual, ms); const Sint64 bpb = (fmt->fmt.adpcm.wSamplesPerBlock * fmt->sample_frame_size); Sint64 skipsize = (offset / bpb) * fmt->wBlockAlign; const Sint64 pos = skipsize + fmt->data_starting_offset; Sint64 rc = SDL_RWseek(internal->rw, pos, RW_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, RW_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, RW_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; SDL_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 *) SDL_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_le16s(rw, &fmt->fmt.adpcm.aCoef[i].iCoef1), NULL, 0); BAIL_IF_MACRO(!read_le16s(rw, &fmt->fmt.adpcm.aCoef[i].iCoef2), NULL, 0); } /* for */ i = sizeof (ADPCMBLOCKHEADER) * fmt->wChannels; fmt->fmt.adpcm.blockheaders = (ADPCMBLOCKHEADER *) SDL_malloc(i); BAIL_IF_MACRO(fmt->fmt.adpcm.blockheaders == NULL, ERR_OUT_OF_MEMORY, 0); return 1; } /* read_fmt_adpcm */ /***************************************************************************** * Everything else... * *****************************************************************************/ static SDL_bool WAV_init(void) { return SDL_TRUE; /* 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_EXTENSIBLE: /* !!! FIXME: this isn't correct */ 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); case FMT_IEEE_FLOAT: SNDDBG(("WAV: Appears to be IEEE float uncompressed audio.\n")); return read_fmt_normal(rw, fmt); /* just normal PCM, otherwise. */ /* add other types here. */ } /* switch */ SNDDBG(("WAV: Format 0x%X is unknown.\n", (unsigned int) fmt->wFormatTag)); BAIL_MACRO("WAV: Unsupported format", 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; Sint64 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_le32s(rw, &siz), NULL, 0); SDL_assert(siz >= 0); pos += (sizeof (Uint32) * 2) + siz; if (siz > 0) BAIL_IF_MACRO(SDL_RWseek(rw, pos, RW_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; 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->wFormatTag == FMT_IEEE_FLOAT) { BAIL_IF_MACRO(fmt->wBitsPerSample != 32, "WAV: Unsupported sample size.", 0); sample->actual.format = AUDIO_F32LSB; } /* if */ else { switch (fmt->wBitsPerSample) { case 4: sample->actual.format = AUDIO_S16SYS; break; case 8: sample->actual.format = AUDIO_U8; break; case 16: sample->actual.format = AUDIO_S16LSB; break; case 24: sample->actual.format = AUDIO_S32SYS; break; case 32: sample->actual.format = AUDIO_S32LSB; break; default: SNDDBG(("WAV: %d bits per sample!?\n", (int) fmt->wBitsPerSample)); BAIL_MACRO("WAV: Unsupported sample size.", 0); } /* switch */ } /* else */ BAIL_IF_MACRO(!read_fmt(rw, fmt), NULL, 0); SDL_RWseek(rw, fmt->next_chunk_offset, RW_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 *) SDL_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; if (fmt->dwAvgBytesPerSec == 0) { /* we assume data is uncompressed if this field is unset. */ fmt->dwAvgBytesPerSec = fmt->sample_frame_size * sample->actual.rate; BAIL_IF_MACRO(fmt->dwAvgBytesPerSec == 0, "WAV: corrupt format chunk?", 0); } 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 *) SDL_calloc(1, sizeof (fmt_t)); BAIL_IF_MACRO(fmt == NULL, ERR_OUT_OF_MEMORY, 0); rc = WAV_open_internal(sample, ext, fmt); if (!rc) { if (fmt->free != NULL) fmt->free(fmt); SDL_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); SDL_free(w->fmt); SDL_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; const Sint64 rc = SDL_RWseek(internal->rw, fmt->data_starting_offset, RW_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 */ static const char *extensions_wav[] = { "WAV", NULL }; const Sound_DecoderFunctions __Sound_DecoderFunctions_WAV = { { extensions_wav, "Microsoft WAVE audio format", "Ryan C. Gordon ", "https://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 */ }; #endif /* SOUND_SUPPORTS_WAV */ /* end of SDL_sound_wav.c ... */