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cog/Frameworks/WavPack/Files/open_utils.c

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////////////////////////////////////////////////////////////////////////////
// **** WAVPACK **** //
// Hybrid Lossless Wavefile Compressor //
// Copyright (c) 1998 - 2016 David Bryant. //
// All Rights Reserved. //
// Distributed under the BSD Software License (see license.txt) //
////////////////////////////////////////////////////////////////////////////
// open_utils.c
// This module provides all the code required to open an existing WavPack file
// for reading by using a reader callback mechanism (NOT a filename). This
// includes the code required to find and parse WavPack blocks, process any
// included metadata, and queue up the bitstreams containing the encoded audio
// data. It does not the actual code to unpack audio data and this was done so
// that programs that just want to query WavPack files for information (like,
// for example, taggers) don't need to link in a lot of unnecessary code.
#include <stdlib.h>
#include <string.h>
#include "wavpack_local.h"
// This function is identical to WavpackOpenFileInput() except that instead
// of providing a filename to open, the caller provides a pointer to a set of
// reader callbacks and instances of up to two streams. The first of these
// streams is required and contains the regular WavPack data stream; the second
// contains the "correction" file if desired. Unlike the standard open
// function which handles the correction file transparently, in this case it
// is the responsibility of the caller to be aware of correction files.
static int seek_eof_information (WavpackContext *wpc, int64_t *final_index, int get_wrapper);
WavpackContext *WavpackOpenFileInputEx64 (WavpackStreamReader64 *reader, void *wv_id, void *wvc_id, char *error, int flags, int norm_offset)
{
WavpackContext *wpc = malloc (sizeof (WavpackContext));
WavpackStream *wps;
int num_blocks = 0;
unsigned char first_byte;
uint32_t bcount;
if (!wpc) {
if (error) strcpy (error, "can't allocate memory");
return NULL;
}
CLEAR (*wpc);
wpc->wv_in = wv_id;
wpc->wvc_in = wvc_id;
wpc->reader = reader;
wpc->total_samples = -1;
wpc->norm_offset = norm_offset;
wpc->max_streams = OLD_MAX_STREAMS; // use this until overwritten with actual number
wpc->open_flags = flags;
wpc->filelen = wpc->reader->get_length (wpc->wv_in);
#ifndef NO_TAGS
if ((flags & (OPEN_TAGS | OPEN_EDIT_TAGS)) && wpc->reader->can_seek (wpc->wv_in)) {
load_tag (wpc);
wpc->reader->set_pos_abs (wpc->wv_in, 0);
if ((flags & OPEN_EDIT_TAGS) && !editable_tag (&wpc->m_tag)) {
if (error) strcpy (error, "can't edit tags located at the beginning of files!");
return WavpackCloseFile (wpc);
}
}
#endif
#ifndef VER4_ONLY
if (wpc->reader->read_bytes (wpc->wv_in, &first_byte, 1) != 1) {
if (error) strcpy (error, "can't read all of WavPack file!");
return WavpackCloseFile (wpc);
}
wpc->reader->push_back_byte (wpc->wv_in, first_byte);
if (first_byte == 'R')
return open_file3 (wpc, error);
#endif
wpc->streams = malloc ((wpc->num_streams = 1) * sizeof (wpc->streams [0]));
if (!wpc->streams) {
if (error) strcpy (error, "can't allocate memory");
return WavpackCloseFile (wpc);
}
wpc->streams [0] = wps = malloc (sizeof (WavpackStream));
if (!wps) {
if (error) strcpy (error, "can't allocate memory");
return WavpackCloseFile (wpc);
}
CLEAR (*wps);
while (!wps->wphdr.block_samples) {
wpc->filepos = wpc->reader->get_pos (wpc->wv_in);
bcount = read_next_header (wpc->reader, wpc->wv_in, &wps->wphdr);
if (bcount == (uint32_t) -1 ||
(!wps->wphdr.block_samples && num_blocks++ > 16)) {
if (error) strcpy (error, "not compatible with this version of WavPack file!");
return WavpackCloseFile (wpc);
}
wpc->filepos += bcount;
wps->blockbuff = malloc (wps->wphdr.ckSize + 8);
if (!wps->blockbuff) {
if (error) strcpy (error, "can't allocate memory");
return WavpackCloseFile (wpc);
}
memcpy (wps->blockbuff, &wps->wphdr, 32);
if (wpc->reader->read_bytes (wpc->wv_in, wps->blockbuff + 32, wps->wphdr.ckSize - 24) != wps->wphdr.ckSize - 24) {
if (error) strcpy (error, "can't read all of WavPack file!");
return WavpackCloseFile (wpc);
}
wps->init_done = FALSE;
if (wps->wphdr.block_samples && !(flags & OPEN_STREAMING)) {
if (GET_BLOCK_INDEX (wps->wphdr) || GET_TOTAL_SAMPLES (wps->wphdr) == -1) {
wpc->initial_index = GET_BLOCK_INDEX (wps->wphdr);
SET_BLOCK_INDEX (wps->wphdr, 0);
if (wpc->reader->can_seek (wpc->wv_in)) {
int64_t final_index = -1;
seek_eof_information (wpc, &final_index, FALSE);
if (final_index != -1)
wpc->total_samples = final_index - wpc->initial_index;
}
}
else
wpc->total_samples = GET_TOTAL_SAMPLES (wps->wphdr);
}
if (wpc->wvc_in && wps->wphdr.block_samples && (wps->wphdr.flags & HYBRID_FLAG)) {
unsigned char ch;
if (wpc->reader->read_bytes (wpc->wvc_in, &ch, 1) == 1) {
wpc->reader->push_back_byte (wpc->wvc_in, ch);
wpc->file2len = wpc->reader->get_length (wpc->wvc_in);
wpc->wvc_flag = TRUE;
}
}
if (wpc->wvc_flag && !read_wvc_block (wpc)) {
if (error) strcpy (error, "not compatible with this version of correction file!");
return WavpackCloseFile (wpc);
}
if (!wps->init_done && !unpack_init (wpc)) {
if (error) strcpy (error, wpc->error_message [0] ? wpc->error_message :
"not compatible with this version of WavPack file!");
return WavpackCloseFile (wpc);
}
wps->init_done = TRUE;
}
wpc->config.flags &= ~0xff;
wpc->config.flags |= wps->wphdr.flags & 0xff;
if (!wpc->config.num_channels) {
wpc->config.num_channels = (wps->wphdr.flags & MONO_FLAG) ? 1 : 2;
wpc->config.channel_mask = 0x5 - wpc->config.num_channels;
}
if ((flags & OPEN_2CH_MAX) && !(wps->wphdr.flags & FINAL_BLOCK))
wpc->reduced_channels = (wps->wphdr.flags & MONO_FLAG) ? 1 : 2;
if (wps->wphdr.flags & DSD_FLAG) {
if (flags & OPEN_DSD_NATIVE) {
wpc->config.bytes_per_sample = 1;
wpc->config.bits_per_sample = 8;
}
else if (flags & OPEN_DSD_AS_PCM) {
wpc->decimation_context = decimate_dsd_init (wpc->reduced_channels ?
wpc->reduced_channels : wpc->config.num_channels);
wpc->config.bytes_per_sample = 3;
wpc->config.bits_per_sample = 24;
}
else {
if (error) strcpy (error, "not configured to handle DSD WavPack files!");
return WavpackCloseFile (wpc);
}
}
else {
wpc->config.bytes_per_sample = (wps->wphdr.flags & BYTES_STORED) + 1;
wpc->config.float_norm_exp = wps->float_norm_exp;
wpc->config.bits_per_sample = (wpc->config.bytes_per_sample * 8) -
((wps->wphdr.flags & SHIFT_MASK) >> SHIFT_LSB);
}
if (!wpc->config.sample_rate) {
if (!wps->wphdr.block_samples || (wps->wphdr.flags & SRATE_MASK) == SRATE_MASK)
wpc->config.sample_rate = 44100;
else
wpc->config.sample_rate = sample_rates [(wps->wphdr.flags & SRATE_MASK) >> SRATE_LSB];
}
return wpc;
}
// This function returns the major version number of the WavPack program
// (or library) that created the open file. Currently, this can be 1 to 5.
// Minor versions are not recorded in WavPack files.
int WavpackGetVersion (WavpackContext *wpc)
{
if (wpc) {
#ifndef VER4_ONLY
if (wpc->stream3)
return get_version3 (wpc);
#endif
return wpc->version_five ? 5 : 4;
}
return 0;
}
// Return the file format specified in the call to WavpackSetFileInformation()
// when the file was created. For all files created prior to WavPack 5.0 this
// will 0 (WP_FORMAT_WAV).
unsigned char WavpackGetFileFormat (WavpackContext *wpc)
{
return wpc->file_format;
}
// Return a string representing the recommended file extension for the open
// WavPack file. For all files created prior to WavPack 5.0 this will be "wav",
// even for raw files with no RIFF into. This string is specified in the
// call to WavpackSetFileInformation() when the file was created.
char *WavpackGetFileExtension (WavpackContext *wpc)
{
if (wpc && wpc->file_extension [0])
return wpc->file_extension;
else
return "wav";
}
// This function initializes everything required to unpack a WavPack block
// and must be called before unpack_samples() is called to obtain audio data.
// It is assumed that the WavpackHeader has been read into the wps->wphdr
// (in the current WavpackStream) and that the entire block has been read at
// wps->blockbuff. If a correction file is available (wpc->wvc_flag = TRUE)
// then the corresponding correction block must be read into wps->block2buff
// and its WavpackHeader has overwritten the header at wps->wphdr. This is
// where all the metadata blocks are scanned including those that contain
// bitstream data.
static int read_metadata_buff (WavpackMetadata *wpmd, unsigned char *blockbuff, unsigned char **buffptr);
static int process_metadata (WavpackContext *wpc, WavpackMetadata *wpmd);
static void bs_open_read (Bitstream *bs, void *buffer_start, void *buffer_end);
int unpack_init (WavpackContext *wpc)
{
WavpackStream *wps = wpc->streams [wpc->current_stream];
unsigned char *blockptr, *block2ptr;
WavpackMetadata wpmd;
wps->num_terms = 0;
wps->mute_error = FALSE;
wps->crc = wps->crc_x = 0xffffffff;
wps->dsd.ready = 0;
CLEAR (wps->wvbits);
CLEAR (wps->wvcbits);
CLEAR (wps->wvxbits);
CLEAR (wps->decorr_passes);
CLEAR (wps->dc);
CLEAR (wps->w);
if (!(wps->wphdr.flags & MONO_FLAG) && wpc->config.num_channels && wps->wphdr.block_samples &&
(wpc->reduced_channels == 1 || wpc->config.num_channels == 1)) {
wps->mute_error = TRUE;
return FALSE;
}
if ((wps->wphdr.flags & UNKNOWN_FLAGS) || (wps->wphdr.flags & MONO_DATA) == MONO_DATA) {
wps->mute_error = TRUE;
return FALSE;
}
blockptr = wps->blockbuff + sizeof (WavpackHeader);
while (read_metadata_buff (&wpmd, wps->blockbuff, &blockptr))
if (!process_metadata (wpc, &wpmd)) {
wps->mute_error = TRUE;
return FALSE;
}
if (wps->wphdr.block_samples && wpc->wvc_flag && wps->block2buff) {
block2ptr = wps->block2buff + sizeof (WavpackHeader);
while (read_metadata_buff (&wpmd, wps->block2buff, &block2ptr))
if (!process_metadata (wpc, &wpmd)) {
wps->mute_error = TRUE;
return FALSE;
}
}
if (wps->wphdr.block_samples && ((wps->wphdr.flags & DSD_FLAG) ? !wps->dsd.ready : !bs_is_open (&wps->wvbits))) {
if (bs_is_open (&wps->wvcbits))
strcpy (wpc->error_message, "can't unpack correction files alone!");
wps->mute_error = TRUE;
return FALSE;
}
if (wps->wphdr.block_samples && !bs_is_open (&wps->wvxbits)) {
if ((wps->wphdr.flags & INT32_DATA) && wps->int32_sent_bits)
wpc->lossy_blocks = TRUE;
if ((wps->wphdr.flags & FLOAT_DATA) &&
wps->float_flags & (FLOAT_EXCEPTIONS | FLOAT_ZEROS_SENT | FLOAT_SHIFT_SENT | FLOAT_SHIFT_SAME))
wpc->lossy_blocks = TRUE;
}
if (wps->wphdr.block_samples)
wps->sample_index = GET_BLOCK_INDEX (wps->wphdr);
return TRUE;
}
//////////////////////////////// matadata handlers ///////////////////////////////
// These functions handle specific metadata types and are called directly
// during WavPack block parsing by process_metadata() at the bottom.
// This function initialzes the main bitstream for audio samples, which must
// be in the "wv" file.
static int init_wv_bitstream (WavpackStream *wps, WavpackMetadata *wpmd)
{
if (!wpmd->byte_length || (wpmd->byte_length & 1))
return FALSE;
bs_open_read (&wps->wvbits, wpmd->data, (unsigned char *) wpmd->data + wpmd->byte_length);
return TRUE;
}
// This function initialzes the "correction" bitstream for audio samples,
// which currently must be in the "wvc" file.
static int init_wvc_bitstream (WavpackStream *wps, WavpackMetadata *wpmd)
{
if (!wpmd->byte_length || (wpmd->byte_length & 1))
return FALSE;
bs_open_read (&wps->wvcbits, wpmd->data, (unsigned char *) wpmd->data + wpmd->byte_length);
return TRUE;
}
// This function initialzes the "extra" bitstream for audio samples which
// contains the information required to losslessly decompress 32-bit float data
// or integer data that exceeds 24 bits. This bitstream is in the "wv" file
// for pure lossless data or the "wvc" file for hybrid lossless. This data
// would not be used for hybrid lossy mode. There is also a 32-bit CRC stored
// in the first 4 bytes of these blocks.
static int init_wvx_bitstream (WavpackStream *wps, WavpackMetadata *wpmd)
{
unsigned char *cp = wpmd->data;
if (wpmd->byte_length <= 4 || (wpmd->byte_length & 1))
return FALSE;
wps->crc_wvx = *cp++;
wps->crc_wvx |= (int32_t) *cp++ << 8;
wps->crc_wvx |= (int32_t) *cp++ << 16;
wps->crc_wvx |= (int32_t) *cp++ << 24;
bs_open_read (&wps->wvxbits, cp, (unsigned char *) wpmd->data + wpmd->byte_length);
return TRUE;
}
// Read the int32 data from the specified metadata into the specified stream.
// This data is used for integer data that has more than 24 bits of magnitude
// or, in some cases, used to eliminate redundant bits from any audio stream.
static int read_int32_info (WavpackStream *wps, WavpackMetadata *wpmd)
{
int bytecnt = wpmd->byte_length;
char *byteptr = wpmd->data;
if (bytecnt != 4)
return FALSE;
wps->int32_sent_bits = *byteptr++;
wps->int32_zeros = *byteptr++;
wps->int32_ones = *byteptr++;
wps->int32_dups = *byteptr;
return TRUE;
}
static int read_float_info (WavpackStream *wps, WavpackMetadata *wpmd)
{
int bytecnt = wpmd->byte_length;
char *byteptr = wpmd->data;
if (bytecnt != 4)
return FALSE;
wps->float_flags = *byteptr++;
wps->float_shift = *byteptr++;
wps->float_max_exp = *byteptr++;
wps->float_norm_exp = *byteptr;
return TRUE;
}
// Read multichannel information from metadata. The first byte is the total
// number of channels and the following bytes represent the channel_mask
// as described for Microsoft WAVEFORMATEX.
static int read_channel_info (WavpackContext *wpc, WavpackMetadata *wpmd)
{
int bytecnt = wpmd->byte_length, shift = 0, mask_bits;
unsigned char *byteptr = wpmd->data;
uint32_t mask = 0;
if (!bytecnt || bytecnt > 7)
return FALSE;
if (!wpc->config.num_channels) {
// if bytecnt is 6 or 7 we are using new configuration with "unlimited" streams
if (bytecnt >= 6) {
wpc->config.num_channels = (byteptr [0] | ((byteptr [2] & 0xf) << 8)) + 1;
wpc->max_streams = (byteptr [1] | ((byteptr [2] & 0xf0) << 4)) + 1;
if (wpc->config.num_channels < wpc->max_streams)
return FALSE;
byteptr += 3;
mask = *byteptr++;
mask |= (uint32_t) *byteptr++ << 8;
mask |= (uint32_t) *byteptr++ << 16;
if (bytecnt == 7) // this was introduced in 5.0
mask |= (uint32_t) *byteptr << 24;
}
else {
wpc->config.num_channels = *byteptr++;
while (--bytecnt) {
mask |= (uint32_t) *byteptr++ << shift;
shift += 8;
}
}
if (wpc->config.num_channels > wpc->max_streams * 2)
return FALSE;
wpc->config.channel_mask = mask;
for (mask_bits = 0; mask; mask >>= 1)
if ((mask & 1) && ++mask_bits > wpc->config.num_channels)
return FALSE;
}
return TRUE;
}
// Read configuration information from metadata.
static int read_config_info (WavpackContext *wpc, WavpackMetadata *wpmd)
{
int bytecnt = wpmd->byte_length;
unsigned char *byteptr = wpmd->data;
if (bytecnt >= 3) {
wpc->config.flags &= 0xff;
wpc->config.flags |= (int32_t) *byteptr++ << 8;
wpc->config.flags |= (int32_t) *byteptr++ << 16;
wpc->config.flags |= (int32_t) *byteptr++ << 24;
bytecnt -= 3;
if (bytecnt && (wpc->config.flags & CONFIG_EXTRA_MODE)) {
wpc->config.xmode = *byteptr++;
bytecnt--;
}
// we used an extra config byte here for the 5.0.0 alpha, so still
// honor it now (but this has been replaced with NEW_CONFIG)
if (bytecnt) {
wpc->config.qmode = (wpc->config.qmode & ~0xff) | *byteptr;
wpc->version_five = 1;
}
}
return TRUE;
}
// Read "new" configuration information from metadata.
static int read_new_config_info (WavpackContext *wpc, WavpackMetadata *wpmd)
{
int bytecnt = wpmd->byte_length;
unsigned char *byteptr = wpmd->data;
wpc->version_five = 1; // just having this block signals version 5.0
wpc->file_format = wpc->config.qmode = wpc->channel_layout = 0;
if (wpc->channel_reordering) {
free (wpc->channel_reordering);
wpc->channel_reordering = NULL;
}
// if there's any data, the first two bytes are file_format and qmode flags
if (bytecnt) {
wpc->file_format = *byteptr++;
wpc->config.qmode = (wpc->config.qmode & ~0xff) | *byteptr++;
bytecnt -= 2;
// another byte indicates a channel layout
if (bytecnt) {
int nchans, i;
wpc->channel_layout = (int32_t) *byteptr++ << 16;
bytecnt--;
// another byte means we have a channel count for the layout and maybe a reordering
if (bytecnt) {
wpc->channel_layout += nchans = *byteptr++;
bytecnt--;
// any more means there's a reordering string
if (bytecnt) {
if (bytecnt > nchans)
return FALSE;
wpc->channel_reordering = malloc (nchans);
// note that redundant reordering info is not stored, so we fill in the rest
if (wpc->channel_reordering) {
for (i = 0; i < nchans; ++i)
if (bytecnt) {
wpc->channel_reordering [i] = *byteptr++;
bytecnt--;
}
else
wpc->channel_reordering [i] = i;
}
}
}
else
wpc->channel_layout += wpc->config.num_channels;
}
}
return TRUE;
}
// Read non-standard sampling rate from metadata.
static int read_sample_rate (WavpackContext *wpc, WavpackMetadata *wpmd)
{
int bytecnt = wpmd->byte_length;
unsigned char *byteptr = wpmd->data;
if (bytecnt == 3 || bytecnt == 4) {
wpc->config.sample_rate = (int32_t) *byteptr++;
wpc->config.sample_rate |= (int32_t) *byteptr++ << 8;
wpc->config.sample_rate |= (int32_t) *byteptr++ << 16;
// for sampling rates > 16777215 (non-audio probably, or ...)
if (bytecnt == 4)
wpc->config.sample_rate |= (int32_t) (*byteptr & 0x7f) << 24;
}
return TRUE;
}
// Read wrapper data from metadata. Currently, this consists of the RIFF
// header and trailer that wav files contain around the audio data but could
// be used for other formats as well. Because WavPack files contain all the
// information required for decoding and playback, this data can probably
// be ignored except when an exact wavefile restoration is needed.
static int read_wrapper_data (WavpackContext *wpc, WavpackMetadata *wpmd)
{
if ((wpc->open_flags & OPEN_WRAPPER) && wpc->wrapper_bytes < MAX_WRAPPER_BYTES && wpmd->byte_length) {
wpc->wrapper_data = realloc (wpc->wrapper_data, wpc->wrapper_bytes + wpmd->byte_length);
if (!wpc->wrapper_data)
return FALSE;
memcpy (wpc->wrapper_data + wpc->wrapper_bytes, wpmd->data, wpmd->byte_length);
wpc->wrapper_bytes += wpmd->byte_length;
}
return TRUE;
}
static int read_metadata_buff (WavpackMetadata *wpmd, unsigned char *blockbuff, unsigned char **buffptr)
{
WavpackHeader *wphdr = (WavpackHeader *) blockbuff;
unsigned char *buffend = blockbuff + wphdr->ckSize + 8;
if (buffend - *buffptr < 2)
return FALSE;
wpmd->id = *(*buffptr)++;
wpmd->byte_length = *(*buffptr)++ << 1;
if (wpmd->id & ID_LARGE) {
wpmd->id &= ~ID_LARGE;
if (buffend - *buffptr < 2)
return FALSE;
wpmd->byte_length += *(*buffptr)++ << 9;
wpmd->byte_length += *(*buffptr)++ << 17;
}
if (wpmd->id & ID_ODD_SIZE) {
if (!wpmd->byte_length) // odd size and zero length makes no sense
return FALSE;
wpmd->id &= ~ID_ODD_SIZE;
wpmd->byte_length--;
}
if (wpmd->byte_length) {
if (buffend - *buffptr < wpmd->byte_length + (wpmd->byte_length & 1)) {
wpmd->data = NULL;
return FALSE;
}
wpmd->data = *buffptr;
(*buffptr) += wpmd->byte_length + (wpmd->byte_length & 1);
}
else
wpmd->data = NULL;
return TRUE;
}
static int process_metadata (WavpackContext *wpc, WavpackMetadata *wpmd)
{
WavpackStream *wps = wpc->streams [wpc->current_stream];
switch (wpmd->id) {
case ID_DUMMY:
return TRUE;
case ID_DECORR_TERMS:
return read_decorr_terms (wps, wpmd);
case ID_DECORR_WEIGHTS:
return read_decorr_weights (wps, wpmd);
case ID_DECORR_SAMPLES:
return read_decorr_samples (wps, wpmd);
case ID_ENTROPY_VARS:
return read_entropy_vars (wps, wpmd);
case ID_HYBRID_PROFILE:
return read_hybrid_profile (wps, wpmd);
case ID_SHAPING_WEIGHTS:
return read_shaping_info (wps, wpmd);
case ID_FLOAT_INFO:
return read_float_info (wps, wpmd);
case ID_INT32_INFO:
return read_int32_info (wps, wpmd);
case ID_CHANNEL_INFO:
return read_channel_info (wpc, wpmd);
case ID_CONFIG_BLOCK:
return read_config_info (wpc, wpmd);
case ID_NEW_CONFIG_BLOCK:
return read_new_config_info (wpc, wpmd);
case ID_SAMPLE_RATE:
return read_sample_rate (wpc, wpmd);
case ID_WV_BITSTREAM:
return init_wv_bitstream (wps, wpmd);
case ID_WVC_BITSTREAM:
return init_wvc_bitstream (wps, wpmd);
case ID_WVX_BITSTREAM:
return init_wvx_bitstream (wps, wpmd);
case ID_DSD_BLOCK:
return init_dsd_block (wpc, wpmd);
case ID_ALT_HEADER: case ID_ALT_TRAILER:
if (!(wpc->open_flags & OPEN_ALT_TYPES))
return TRUE;
case ID_RIFF_HEADER: case ID_RIFF_TRAILER:
return read_wrapper_data (wpc, wpmd);
case ID_ALT_MD5_CHECKSUM:
if (!(wpc->open_flags & OPEN_ALT_TYPES))
return TRUE;
case ID_MD5_CHECKSUM:
if (wpmd->byte_length == 16) {
memcpy (wpc->config.md5_checksum, wpmd->data, 16);
wpc->config.flags |= CONFIG_MD5_CHECKSUM;
wpc->config.md5_read = 1;
}
return TRUE;
case ID_ALT_EXTENSION:
if (wpmd->byte_length && wpmd->byte_length < sizeof (wpc->file_extension)) {
memcpy (wpc->file_extension, wpmd->data, wpmd->byte_length);
wpc->file_extension [wpmd->byte_length] = 0;
}
default:
return (wpmd->id & ID_OPTIONAL_DATA) ? TRUE : FALSE;
}
}
//////////////////////////////// bitstream management ///////////////////////////////
// Open the specified BitStream and associate with the specified buffer.
static void bs_read (Bitstream *bs);
static void bs_open_read (Bitstream *bs, void *buffer_start, void *buffer_end)
{
bs->error = bs->sr = bs->bc = 0;
bs->ptr = (bs->buf = buffer_start) - 1;
bs->end = buffer_end;
bs->wrap = bs_read;
}
// This function is only called from the getbit() and getbits() macros when
// the BitStream has been exhausted and more data is required. Sinve these
// bistreams no longer access files, this function simple sets an error and
// resets the buffer.
static void bs_read (Bitstream *bs)
{
bs->ptr = bs->buf;
bs->error = 1;
}
// This function is called to close the bitstream. It returns the number of
// full bytes actually read as bits.
uint32_t bs_close_read (Bitstream *bs)
{
uint32_t bytes_read;
if (bs->bc < sizeof (*(bs->ptr)) * 8)
bs->ptr++;
bytes_read = (uint32_t)(bs->ptr - bs->buf) * sizeof (*(bs->ptr));
if (!(bytes_read & 1))
++bytes_read;
CLEAR (*bs);
return bytes_read;
}
// Normally the trailing wrapper will not be available when a WavPack file is first
// opened for reading because it is stored in the final block of the file. This
// function forces a seek to the end of the file to pick up any trailing wrapper
// stored there (then use WavPackGetWrapper**() to obtain). This can obviously only
// be used for seekable files (not pipes) and is not available for pre-4.0 WavPack
// files.
void WavpackSeekTrailingWrapper (WavpackContext *wpc)
{
if ((wpc->open_flags & OPEN_WRAPPER) &&
wpc->reader->can_seek (wpc->wv_in) && !wpc->stream3)
seek_eof_information (wpc, NULL, TRUE);
}
// Get any MD5 checksum stored in the metadata (should be called after reading
// last sample or an extra seek will occur). A return value of FALSE indicates
// that no MD5 checksum was stored.
int WavpackGetMD5Sum (WavpackContext *wpc, unsigned char data [16])
{
if (wpc->config.flags & CONFIG_MD5_CHECKSUM) {
if (!wpc->config.md5_read && wpc->reader->can_seek (wpc->wv_in))
seek_eof_information (wpc, NULL, FALSE);
if (wpc->config.md5_read) {
memcpy (data, wpc->config.md5_checksum, 16);
return TRUE;
}
}
return FALSE;
}
// Read from current file position until a valid 32-byte WavPack 4.0 header is
// found and read into the specified pointer. The number of bytes skipped is
// returned. If no WavPack header is found within 1 meg, then a -1 is returned
// to indicate the error. No additional bytes are read past the header and it
// is returned in the processor's native endian mode. Seeking is not required.
uint32_t read_next_header (WavpackStreamReader64 *reader, void *id, WavpackHeader *wphdr)
{
unsigned char buffer [sizeof (*wphdr)], *sp = buffer + sizeof (*wphdr), *ep = sp;
uint32_t bytes_skipped = 0;
int bleft;
while (1) {
if (sp < ep) {
bleft = (int)(ep - sp);
memmove (buffer, sp, bleft);
}
else
bleft = 0;
if (reader->read_bytes (id, buffer + bleft, sizeof (*wphdr) - bleft) != sizeof (*wphdr) - bleft)
return -1;
sp = buffer;
if (*sp++ == 'w' && *sp == 'v' && *++sp == 'p' && *++sp == 'k' &&
!(*++sp & 1) && sp [2] < 16 && !sp [3] && (sp [2] || sp [1] || *sp >= 24) && sp [5] == 4 &&
sp [4] >= (MIN_STREAM_VERS & 0xff) && sp [4] <= (MAX_STREAM_VERS & 0xff) && sp [18] < 3 && !sp [19]) {
memcpy (wphdr, buffer, sizeof (*wphdr));
WavpackLittleEndianToNative (wphdr, WavpackHeaderFormat);
return bytes_skipped;
}
while (sp < ep && *sp != 'w')
sp++;
if ((bytes_skipped += (uint32_t)(sp - buffer)) > 1024 * 1024)
return -1;
}
}
// Compare the regular wv file block header to a potential matching wvc
// file block header and return action code based on analysis:
//
// 0 = use wvc block (assuming rest of block is readable)
// 1 = bad match; try to read next wvc block
// -1 = bad match; ignore wvc file for this block and backup fp (if
// possible) and try to use this block next time
static int match_wvc_header (WavpackHeader *wv_hdr, WavpackHeader *wvc_hdr)
{
if (GET_BLOCK_INDEX (*wv_hdr) == GET_BLOCK_INDEX (*wvc_hdr) &&
wv_hdr->block_samples == wvc_hdr->block_samples) {
int wvi = 0, wvci = 0;
if (wv_hdr->flags == wvc_hdr->flags)
return 0;
if (wv_hdr->flags & INITIAL_BLOCK)
wvi -= 1;
if (wv_hdr->flags & FINAL_BLOCK)
wvi += 1;
if (wvc_hdr->flags & INITIAL_BLOCK)
wvci -= 1;
if (wvc_hdr->flags & FINAL_BLOCK)
wvci += 1;
return (wvci - wvi < 0) ? 1 : -1;
}
if (GET_BLOCK_INDEX (*wvc_hdr) > GET_BLOCK_INDEX (*wv_hdr))
return 1;
else
return -1;
}
// Read the wvc block that matches the regular wv block that has been
// read for the current stream. If an exact match is not found then
// we either keep reading or back up and (possibly) use the block
// later. The skip_wvc flag is set if not matching wvc block is found
// so that we can still decode using only the lossy version (although
// we flag this as an error). A return of FALSE indicates a serious
// error (not just that we missed one wvc block).
int read_wvc_block (WavpackContext *wpc)
{
WavpackStream *wps = wpc->streams [wpc->current_stream];
int64_t bcount, file2pos;
WavpackHeader wphdr;
int compare_result;
while (1) {
file2pos = wpc->reader->get_pos (wpc->wvc_in);
bcount = read_next_header (wpc->reader, wpc->wvc_in, &wphdr);
if (bcount == (uint32_t) -1) {
wps->wvc_skip = TRUE;
wpc->crc_errors++;
return FALSE;
}
if (wpc->open_flags & OPEN_STREAMING)
SET_BLOCK_INDEX (wphdr, wps->sample_index = 0);
else
SET_BLOCK_INDEX (wphdr, GET_BLOCK_INDEX (wphdr) - wpc->initial_index);
if (wphdr.flags & INITIAL_BLOCK)
wpc->file2pos = file2pos + bcount;
compare_result = match_wvc_header (&wps->wphdr, &wphdr);
if (!compare_result) {
wps->block2buff = malloc (wphdr.ckSize + 8);
if (!wps->block2buff)
return FALSE;
memcpy (wps->block2buff, &wphdr, 32);
if (wpc->reader->read_bytes (wpc->wvc_in, wps->block2buff + 32, wphdr.ckSize - 24) !=
wphdr.ckSize - 24 || (wphdr.flags & UNKNOWN_FLAGS)) {
free (wps->block2buff);
wps->block2buff = NULL;
wps->wvc_skip = TRUE;
wpc->crc_errors++;
return FALSE;
}
wps->wvc_skip = FALSE;
memcpy (&wps->wphdr, &wphdr, 32);
return TRUE;
}
else if (compare_result == -1) {
wps->wvc_skip = TRUE;
wpc->reader->set_pos_rel (wpc->wvc_in, -32, SEEK_CUR);
wpc->crc_errors++;
return TRUE;
}
}
}
// This function is used to seek to end of a file to obtain certain information
// that is stored there at the file creation time because it is not known at
// the start. This includes the MD5 sum and and trailing part of the file
// wrapper, and in some rare cases may include the total number of samples in
// the file (although we usually try to back up and write that at the front of
// the file). Note this function restores the file position to its original
// location (and obviously requires a seekable file). The normal return value
// is TRUE indicating no errors, although this does not actually mean that any
// information was retrieved. An error return of FALSE usually means the file
// terminated unexpectedly. Note that this could be used to get all three
// types of information in one go, but it's not actually used that way now.
static int seek_eof_information (WavpackContext *wpc, int64_t *final_index, int get_wrapper)
{
int64_t restore_pos, last_pos = -1;
WavpackStreamReader64 *reader = wpc->reader;
int alt_types = wpc->open_flags & OPEN_ALT_TYPES;
uint32_t blocks = 0, audio_blocks = 0;
void *id = wpc->wv_in;
WavpackHeader wphdr;
restore_pos = reader->get_pos (id); // we restore file position when done
// start 1MB from the end-of-file, or from the start if the file is not that big
if (reader->get_length (id) > 1048576LL)
reader->set_pos_rel (id, -1048576, SEEK_END);
else
reader->set_pos_abs (id, 0);
// Note that we go backward (without parsing inside blocks) until we find a block
// with audio (careful to not get stuck in a loop). Only then do we go forward
// parsing all blocks in their entirety.
while (1) {
uint32_t bcount = read_next_header (reader, id, &wphdr);
int64_t current_pos = reader->get_pos (id);
// if we just got to the same place as last time, we're stuck and need to give up
if (current_pos == last_pos) {
reader->set_pos_abs (id, restore_pos);
return FALSE;
}
last_pos = current_pos;
// We enter here if we just read 1 MB without seeing any WavPack block headers.
// Since WavPack blocks are < 1 MB, that means we're in a big APE tag, or we got
// to the end-of-file.
if (bcount == (uint32_t) -1) {
// if we have not seen any blocks at all yet, back up almost 2 MB (or to the
// beginning of the file) and try again
if (!blocks) {
if (current_pos > 2000000LL)
reader->set_pos_rel (id, -2000000, SEEK_CUR);
else
reader->set_pos_abs (id, 0);
continue;
}
// if we have seen WavPack blocks, then this means we've done all we can do here
reader->set_pos_abs (id, restore_pos);
return TRUE;
}
blocks++;
// If the block has audio samples, calculate a final index, although this is not
// final since this may not be the last block with audio. On the other hand, if
// this block does not have audio, and we haven't seen one with audio, we have
// to go back some more.
if (wphdr.block_samples) {
if (final_index)
*final_index = GET_BLOCK_INDEX (wphdr) + wphdr.block_samples;
audio_blocks++;
}
else if (!audio_blocks) {
if (current_pos > 1048576LL)
reader->set_pos_rel (id, -1048576, SEEK_CUR);
else
reader->set_pos_abs (id, 0);
continue;
}
// at this point we have seen at least one block with audio, so we parse the
// entire block looking for MD5 metadata or (conditionally) trailing wrappers
bcount = wphdr.ckSize - sizeof (WavpackHeader) + 8;
while (bcount >= 2) {
unsigned char meta_id, c1, c2;
uint32_t meta_bc, meta_size;
if (reader->read_bytes (id, &meta_id, 1) != 1 ||
reader->read_bytes (id, &c1, 1) != 1) {
reader->set_pos_abs (id, restore_pos);
return FALSE;
}
meta_bc = c1 << 1;
bcount -= 2;
if (meta_id & ID_LARGE) {
if (bcount < 2 || reader->read_bytes (id, &c1, 1) != 1 ||
reader->read_bytes (id, &c2, 1) != 1) {
reader->set_pos_abs (id, restore_pos);
return FALSE;
}
meta_bc += ((uint32_t) c1 << 9) + ((uint32_t) c2 << 17);
bcount -= 2;
}
meta_size = (meta_id & ID_ODD_SIZE) ? meta_bc - 1 : meta_bc;
meta_id &= ID_UNIQUE;
if (get_wrapper && (meta_id == ID_RIFF_TRAILER || (alt_types && meta_id == ID_ALT_TRAILER)) && meta_bc) {
wpc->wrapper_data = realloc (wpc->wrapper_data, wpc->wrapper_bytes + meta_bc);
if (!wpc->wrapper_data) {
reader->set_pos_abs (id, restore_pos);
return FALSE;
}
if (reader->read_bytes (id, wpc->wrapper_data + wpc->wrapper_bytes, meta_bc) == meta_bc)
wpc->wrapper_bytes += meta_size;
else {
reader->set_pos_abs (id, restore_pos);
return FALSE;
}
}
else if (meta_id == ID_MD5_CHECKSUM || (alt_types && meta_id == ID_ALT_MD5_CHECKSUM)) {
if (meta_bc == 16 && bcount >= 16) {
if (reader->read_bytes (id, wpc->config.md5_checksum, 16) == 16)
wpc->config.md5_read = TRUE;
else {
reader->set_pos_abs (id, restore_pos);
return FALSE;
}
}
else
reader->set_pos_rel (id, meta_bc, SEEK_CUR);
}
else
reader->set_pos_rel (id, meta_bc, SEEK_CUR);
bcount -= meta_bc;
}
}
}
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