ref: 827020f6863490c649470087008ab5ca8138afc0
dir: /sys/src/cmd/audio/libFLAC/bitwriter.c/
/* libFLAC - Free Lossless Audio Codec library
* Copyright (C) 2000-2009 Josh Coalson
* Copyright (C) 2011-2014 Xiph.Org Foundation
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the name of the Xiph.org Foundation nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <stdlib.h>
#include <string.h>
#include "private/bitwriter.h"
#include "private/crc.h"
#include "private/macros.h"
#include "FLAC/assert.h"
#include "share/alloc.h"
#include "share/compat.h"
#include "share/endswap.h"
/* Things should be fastest when this matches the machine word size */
/* WATCHOUT: if you change this you must also change the following #defines down to SWAP_BE_WORD_TO_HOST below to match */
/* WATCHOUT: there are a few places where the code will not work unless uint32_t is >= 32 bits wide */
#define FLAC__BYTES_PER_WORD 4
#define FLAC__BITS_PER_WORD 32
#define FLAC__WORD_ALL_ONES ((FLAC__uint32)0xffffffff)
/* SWAP_BE_WORD_TO_HOST swaps bytes in a uint32_t (which is always big-endian) if necessary to match host byte order */
#if WORDS_BIGENDIAN
#define SWAP_BE_WORD_TO_HOST(x) (x)
#else
#define SWAP_BE_WORD_TO_HOST(x) ENDSWAP_32(x)
#endif
/*
* The default capacity here doesn't matter too much. The buffer always grows
* to hold whatever is written to it. Usually the encoder will stop adding at
* a frame or metadata block, then write that out and clear the buffer for the
* next one.
*/
static const unsigned FLAC__BITWRITER_DEFAULT_CAPACITY = 32768u / sizeof(uint32_t); /* size in words */
/* When growing, increment 4K at a time */
static const unsigned FLAC__BITWRITER_DEFAULT_INCREMENT = 4096u / sizeof(uint32_t); /* size in words */
#define FLAC__WORDS_TO_BITS(words) ((words) * FLAC__BITS_PER_WORD)
#define FLAC__TOTAL_BITS(bw) (FLAC__WORDS_TO_BITS((bw)->words) + (bw)->bits)
struct FLAC__BitWriter {
uint32_t *buffer;
uint32_t accum; /* accumulator; bits are right-justified; when full, accum is appended to buffer */
unsigned capacity; /* capacity of buffer in words */
unsigned words; /* # of complete words in buffer */
unsigned bits; /* # of used bits in accum */
};
/* * WATCHOUT: The current implementation only grows the buffer. */
#ifndef __SUNPRO_C
static
#endif
FLAC__bool bitwriter_grow_(FLAC__BitWriter *bw, unsigned bits_to_add)
{
unsigned new_capacity;
uint32_t *new_buffer;
FLAC__ASSERT(0 != bw);
FLAC__ASSERT(0 != bw->buffer);
/* calculate total words needed to store 'bits_to_add' additional bits */
new_capacity = bw->words + ((bw->bits + bits_to_add + FLAC__BITS_PER_WORD - 1) / FLAC__BITS_PER_WORD);
/* it's possible (due to pessimism in the growth estimation that
* leads to this call) that we don't actually need to grow
*/
if(bw->capacity >= new_capacity)
return true;
/* round up capacity increase to the nearest FLAC__BITWRITER_DEFAULT_INCREMENT */
if((new_capacity - bw->capacity) % FLAC__BITWRITER_DEFAULT_INCREMENT)
new_capacity += FLAC__BITWRITER_DEFAULT_INCREMENT - ((new_capacity - bw->capacity) % FLAC__BITWRITER_DEFAULT_INCREMENT);
/* make sure we got everything right */
FLAC__ASSERT(0 == (new_capacity - bw->capacity) % FLAC__BITWRITER_DEFAULT_INCREMENT);
FLAC__ASSERT(new_capacity > bw->capacity);
FLAC__ASSERT(new_capacity >= bw->words + ((bw->bits + bits_to_add + FLAC__BITS_PER_WORD - 1) / FLAC__BITS_PER_WORD));
new_buffer = safe_realloc_mul_2op_(bw->buffer, sizeof(uint32_t), /*times*/new_capacity);
if(new_buffer == 0)
return false;
bw->buffer = new_buffer;
bw->capacity = new_capacity;
return true;
}
/***********************************************************************
*
* Class constructor/destructor
*
***********************************************************************/
FLAC__BitWriter *FLAC__bitwriter_new(void)
{
FLAC__BitWriter *bw = calloc(1, sizeof(FLAC__BitWriter));
/* note that calloc() sets all members to 0 for us */
return bw;
}
void FLAC__bitwriter_delete(FLAC__BitWriter *bw)
{
FLAC__ASSERT(0 != bw);
FLAC__bitwriter_free(bw);
free(bw);
}
/***********************************************************************
*
* Public class methods
*
***********************************************************************/
FLAC__bool FLAC__bitwriter_init(FLAC__BitWriter *bw)
{
FLAC__ASSERT(0 != bw);
bw->words = bw->bits = 0;
bw->capacity = FLAC__BITWRITER_DEFAULT_CAPACITY;
bw->buffer = malloc(sizeof(uint32_t) * bw->capacity);
if(bw->buffer == 0)
return false;
return true;
}
void FLAC__bitwriter_free(FLAC__BitWriter *bw)
{
FLAC__ASSERT(0 != bw);
if(0 != bw->buffer)
free(bw->buffer);
bw->buffer = 0;
bw->capacity = 0;
bw->words = bw->bits = 0;
}
void FLAC__bitwriter_clear(FLAC__BitWriter *bw)
{
bw->words = bw->bits = 0;
}
void FLAC__bitwriter_dump(const FLAC__BitWriter *bw, FILE *out)
{
unsigned i, j;
if(bw == 0) {
fprintf(out, "bitwriter is NULL\n");
}
else {
fprintf(out, "bitwriter: capacity=%u words=%u bits=%u total_bits=%u\n", bw->capacity, bw->words, bw->bits, FLAC__TOTAL_BITS(bw));
for(i = 0; i < bw->words; i++) {
fprintf(out, "%08X: ", i);
for(j = 0; j < FLAC__BITS_PER_WORD; j++)
fprintf(out, "%01u", bw->buffer[i] & (1 << (FLAC__BITS_PER_WORD-j-1)) ? 1:0);
fprintf(out, "\n");
}
if(bw->bits > 0) {
fprintf(out, "%08X: ", i);
for(j = 0; j < bw->bits; j++)
fprintf(out, "%01u", bw->accum & (1 << (bw->bits-j-1)) ? 1:0);
fprintf(out, "\n");
}
}
}
FLAC__bool FLAC__bitwriter_get_write_crc16(FLAC__BitWriter *bw, FLAC__uint16 *crc)
{
const FLAC__byte *buffer;
size_t bytes;
FLAC__ASSERT((bw->bits & 7) == 0); /* assert that we're byte-aligned */
if(!FLAC__bitwriter_get_buffer(bw, &buffer, &bytes))
return false;
*crc = (FLAC__uint16)FLAC__crc16(buffer, bytes);
FLAC__bitwriter_release_buffer(bw);
return true;
}
FLAC__bool FLAC__bitwriter_get_write_crc8(FLAC__BitWriter *bw, FLAC__byte *crc)
{
const FLAC__byte *buffer;
size_t bytes;
FLAC__ASSERT((bw->bits & 7) == 0); /* assert that we're byte-aligned */
if(!FLAC__bitwriter_get_buffer(bw, &buffer, &bytes))
return false;
*crc = FLAC__crc8(buffer, bytes);
FLAC__bitwriter_release_buffer(bw);
return true;
}
FLAC__bool FLAC__bitwriter_is_byte_aligned(const FLAC__BitWriter *bw)
{
return ((bw->bits & 7) == 0);
}
unsigned FLAC__bitwriter_get_input_bits_unconsumed(const FLAC__BitWriter *bw)
{
return FLAC__TOTAL_BITS(bw);
}
FLAC__bool FLAC__bitwriter_get_buffer(FLAC__BitWriter *bw, const FLAC__byte **buffer, size_t *bytes)
{
FLAC__ASSERT((bw->bits & 7) == 0);
/* double protection */
if(bw->bits & 7)
return false;
/* if we have bits in the accumulator we have to flush those to the buffer first */
if(bw->bits) {
FLAC__ASSERT(bw->words <= bw->capacity);
if(bw->words == bw->capacity && !bitwriter_grow_(bw, FLAC__BITS_PER_WORD))
return false;
/* append bits as complete word to buffer, but don't change bw->accum or bw->bits */
bw->buffer[bw->words] = SWAP_BE_WORD_TO_HOST(bw->accum << (FLAC__BITS_PER_WORD-bw->bits));
}
/* now we can just return what we have */
*buffer = (FLAC__byte*)bw->buffer;
*bytes = (FLAC__BYTES_PER_WORD * bw->words) + (bw->bits >> 3);
return true;
}
void FLAC__bitwriter_release_buffer(FLAC__BitWriter *bw)
{
/* nothing to do. in the future, strict checking of a 'writer-is-in-
* get-mode' flag could be added everywhere and then cleared here
*/
(void)bw;
}
inline FLAC__bool FLAC__bitwriter_write_zeroes(FLAC__BitWriter *bw, unsigned bits)
{
unsigned n;
FLAC__ASSERT(0 != bw);
FLAC__ASSERT(0 != bw->buffer);
if(bits == 0)
return true;
/* slightly pessimistic size check but faster than "<= bw->words + (bw->bits+bits+FLAC__BITS_PER_WORD-1)/FLAC__BITS_PER_WORD" */
if(bw->capacity <= bw->words + bits && !bitwriter_grow_(bw, bits))
return false;
/* first part gets to word alignment */
if(bw->bits) {
n = flac_min(FLAC__BITS_PER_WORD - bw->bits, bits);
bw->accum <<= n;
bits -= n;
bw->bits += n;
if(bw->bits == FLAC__BITS_PER_WORD) {
bw->buffer[bw->words++] = SWAP_BE_WORD_TO_HOST(bw->accum);
bw->bits = 0;
}
else
return true;
}
/* do whole words */
while(bits >= FLAC__BITS_PER_WORD) {
bw->buffer[bw->words++] = 0;
bits -= FLAC__BITS_PER_WORD;
}
/* do any leftovers */
if(bits > 0) {
bw->accum = 0;
bw->bits = bits;
}
return true;
}
inline FLAC__bool FLAC__bitwriter_write_raw_uint32(FLAC__BitWriter *bw, FLAC__uint32 val, unsigned bits)
{
register unsigned left;
/* WATCHOUT: code does not work with <32bit words; we can make things much faster with this assertion */
FLAC__ASSERT(FLAC__BITS_PER_WORD >= 32);
FLAC__ASSERT(0 != bw);
FLAC__ASSERT(0 != bw->buffer);
FLAC__ASSERT(bits <= 32);
if(bits == 0)
return true;
/* slightly pessimistic size check but faster than "<= bw->words + (bw->bits+bits+FLAC__BITS_PER_WORD-1)/FLAC__BITS_PER_WORD" */
if(bw->capacity <= bw->words + bits && !bitwriter_grow_(bw, bits))
return false;
left = FLAC__BITS_PER_WORD - bw->bits;
if(bits < left) {
bw->accum <<= bits;
bw->accum |= val;
bw->bits += bits;
}
else if(bw->bits) { /* WATCHOUT: if bw->bits == 0, left==FLAC__BITS_PER_WORD and bw->accum<<=left is a NOP instead of setting to 0 */
bw->accum <<= left;
bw->accum |= val >> (bw->bits = bits - left);
bw->buffer[bw->words++] = SWAP_BE_WORD_TO_HOST(bw->accum);
bw->accum = val;
}
else {
bw->accum = val;
bw->bits = 0;
bw->buffer[bw->words++] = SWAP_BE_WORD_TO_HOST(val);
}
return true;
}
inline FLAC__bool FLAC__bitwriter_write_raw_int32(FLAC__BitWriter *bw, FLAC__int32 val, unsigned bits)
{
/* zero-out unused bits */
if(bits < 32)
val &= (~(0xffffffff << bits));
return FLAC__bitwriter_write_raw_uint32(bw, (FLAC__uint32)val, bits);
}
inline FLAC__bool FLAC__bitwriter_write_raw_uint64(FLAC__BitWriter *bw, FLAC__uint64 val, unsigned bits)
{
/* this could be a little faster but it's not used for much */
if(bits > 32) {
return
FLAC__bitwriter_write_raw_uint32(bw, (FLAC__uint32)(val>>32), bits-32) &&
FLAC__bitwriter_write_raw_uint32(bw, (FLAC__uint32)val, 32);
}
else
return FLAC__bitwriter_write_raw_uint32(bw, (FLAC__uint32)val, bits);
}
inline FLAC__bool FLAC__bitwriter_write_raw_uint32_little_endian(FLAC__BitWriter *bw, FLAC__uint32 val)
{
/* this doesn't need to be that fast as currently it is only used for vorbis comments */
if(!FLAC__bitwriter_write_raw_uint32(bw, val & 0xff, 8))
return false;
if(!FLAC__bitwriter_write_raw_uint32(bw, (val>>8) & 0xff, 8))
return false;
if(!FLAC__bitwriter_write_raw_uint32(bw, (val>>16) & 0xff, 8))
return false;
if(!FLAC__bitwriter_write_raw_uint32(bw, val>>24, 8))
return false;
return true;
}
inline FLAC__bool FLAC__bitwriter_write_byte_block(FLAC__BitWriter *bw, const FLAC__byte vals[], unsigned nvals)
{
unsigned i;
/* this could be faster but currently we don't need it to be since it's only used for writing metadata */
for(i = 0; i < nvals; i++) {
if(!FLAC__bitwriter_write_raw_uint32(bw, (FLAC__uint32)(vals[i]), 8))
return false;
}
return true;
}
FLAC__bool FLAC__bitwriter_write_unary_unsigned(FLAC__BitWriter *bw, unsigned val)
{
if(val < 32)
return FLAC__bitwriter_write_raw_uint32(bw, 1, ++val);
else
return
FLAC__bitwriter_write_zeroes(bw, val) &&
FLAC__bitwriter_write_raw_uint32(bw, 1, 1);
}
unsigned FLAC__bitwriter_rice_bits(FLAC__int32 val, unsigned parameter)
{
FLAC__uint32 uval;
FLAC__ASSERT(parameter < sizeof(unsigned)*8);
/* fold signed to unsigned; actual formula is: negative(v)? -2v-1 : 2v */
uval = (val<<1) ^ (val>>31);
return 1 + parameter + (uval >> parameter);
}
#if 0 /* UNUSED */
unsigned FLAC__bitwriter_golomb_bits_signed(int val, unsigned parameter)
{
unsigned bits, msbs, uval;
unsigned k;
FLAC__ASSERT(parameter > 0);
/* fold signed to unsigned */
if(val < 0)
uval = (unsigned)(((-(++val)) << 1) + 1);
else
uval = (unsigned)(val << 1);
k = FLAC__bitmath_ilog2(parameter);
if(parameter == 1u<<k) {
FLAC__ASSERT(k <= 30);
msbs = uval >> k;
bits = 1 + k + msbs;
}
else {
unsigned q, r, d;
d = (1 << (k+1)) - parameter;
q = uval / parameter;
r = uval - (q * parameter);
bits = 1 + q + k;
if(r >= d)
bits++;
}
return bits;
}
unsigned FLAC__bitwriter_golomb_bits_unsigned(unsigned uval, unsigned parameter)
{
unsigned bits, msbs;
unsigned k;
FLAC__ASSERT(parameter > 0);
k = FLAC__bitmath_ilog2(parameter);
if(parameter == 1u<<k) {
FLAC__ASSERT(k <= 30);
msbs = uval >> k;
bits = 1 + k + msbs;
}
else {
unsigned q, r, d;
d = (1 << (k+1)) - parameter;
q = uval / parameter;
r = uval - (q * parameter);
bits = 1 + q + k;
if(r >= d)
bits++;
}
return bits;
}
#endif /* UNUSED */
FLAC__bool FLAC__bitwriter_write_rice_signed(FLAC__BitWriter *bw, FLAC__int32 val, unsigned parameter)
{
unsigned total_bits, interesting_bits, msbs;
FLAC__uint32 uval, pattern;
FLAC__ASSERT(0 != bw);
FLAC__ASSERT(0 != bw->buffer);
FLAC__ASSERT(parameter < 8*sizeof(uval));
/* fold signed to unsigned; actual formula is: negative(v)? -2v-1 : 2v */
uval = (val<<1) ^ (val>>31);
msbs = uval >> parameter;
interesting_bits = 1 + parameter;
total_bits = interesting_bits + msbs;
pattern = 1 << parameter; /* the unary end bit */
pattern |= (uval & ((1<<parameter)-1)); /* the binary LSBs */
if(total_bits <= 32)
return FLAC__bitwriter_write_raw_uint32(bw, pattern, total_bits);
else
return
FLAC__bitwriter_write_zeroes(bw, msbs) && /* write the unary MSBs */
FLAC__bitwriter_write_raw_uint32(bw, pattern, interesting_bits); /* write the unary end bit and binary LSBs */
}
FLAC__bool FLAC__bitwriter_write_rice_signed_block(FLAC__BitWriter *bw, const FLAC__int32 *vals, unsigned nvals, unsigned parameter)
{
const FLAC__uint32 mask1 = FLAC__WORD_ALL_ONES << parameter; /* we val|=mask1 to set the stop bit above it... */
const FLAC__uint32 mask2 = FLAC__WORD_ALL_ONES >> (31-parameter); /* ...then mask off the bits above the stop bit with val&=mask2*/
FLAC__uint32 uval;
unsigned left;
const unsigned lsbits = 1 + parameter;
unsigned msbits;
FLAC__ASSERT(0 != bw);
FLAC__ASSERT(0 != bw->buffer);
FLAC__ASSERT(parameter < 8*sizeof(uint32_t)-1);
/* WATCHOUT: code does not work with <32bit words; we can make things much faster with this assertion */
FLAC__ASSERT(FLAC__BITS_PER_WORD >= 32);
while(nvals) {
/* fold signed to unsigned; actual formula is: negative(v)? -2v-1 : 2v */
uval = (*vals<<1) ^ (*vals>>31);
msbits = uval >> parameter;
if(bw->bits && bw->bits + msbits + lsbits < FLAC__BITS_PER_WORD) { /* i.e. if the whole thing fits in the current uint32_t */
/* ^^^ if bw->bits is 0 then we may have filled the buffer and have no free uint32_t to work in */
bw->bits = bw->bits + msbits + lsbits;
uval |= mask1; /* set stop bit */
uval &= mask2; /* mask off unused top bits */
bw->accum <<= msbits + lsbits;
bw->accum |= uval;
}
else {
/* slightly pessimistic size check but faster than "<= bw->words + (bw->bits+msbits+lsbits+FLAC__BITS_PER_WORD-1)/FLAC__BITS_PER_WORD" */
/* OPT: pessimism may cause flurry of false calls to grow_ which eat up all savings before it */
if(bw->capacity <= bw->words + bw->bits + msbits + 1/*lsbits always fit in 1 uint32_t*/ && !bitwriter_grow_(bw, msbits+lsbits))
return false;
if(msbits) {
/* first part gets to word alignment */
if(bw->bits) {
left = FLAC__BITS_PER_WORD - bw->bits;
if(msbits < left) {
bw->accum <<= msbits;
bw->bits += msbits;
goto break1;
}
else {
bw->accum <<= left;
msbits -= left;
bw->buffer[bw->words++] = SWAP_BE_WORD_TO_HOST(bw->accum);
bw->bits = 0;
}
}
/* do whole words */
while(msbits >= FLAC__BITS_PER_WORD) {
bw->buffer[bw->words++] = 0;
msbits -= FLAC__BITS_PER_WORD;
}
/* do any leftovers */
if(msbits > 0) {
bw->accum = 0;
bw->bits = msbits;
}
}
break1:
uval |= mask1; /* set stop bit */
uval &= mask2; /* mask off unused top bits */
left = FLAC__BITS_PER_WORD - bw->bits;
if(lsbits < left) {
bw->accum <<= lsbits;
bw->accum |= uval;
bw->bits += lsbits;
}
else {
/* if bw->bits == 0, left==FLAC__BITS_PER_WORD which will always
* be > lsbits (because of previous assertions) so it would have
* triggered the (lsbits<left) case above.
*/
FLAC__ASSERT(bw->bits);
FLAC__ASSERT(left < FLAC__BITS_PER_WORD);
bw->accum <<= left;
bw->accum |= uval >> (bw->bits = lsbits - left);
bw->buffer[bw->words++] = SWAP_BE_WORD_TO_HOST(bw->accum);
bw->accum = uval;
}
}
vals++;
nvals--;
}
return true;
}
#if 0 /* UNUSED */
FLAC__bool FLAC__bitwriter_write_golomb_signed(FLAC__BitWriter *bw, int val, unsigned parameter)
{
unsigned total_bits, msbs, uval;
unsigned k;
FLAC__ASSERT(0 != bw);
FLAC__ASSERT(0 != bw->buffer);
FLAC__ASSERT(parameter > 0);
/* fold signed to unsigned */
if(val < 0)
uval = (unsigned)(((-(++val)) << 1) + 1);
else
uval = (unsigned)(val << 1);
k = FLAC__bitmath_ilog2(parameter);
if(parameter == 1u<<k) {
unsigned pattern;
FLAC__ASSERT(k <= 30);
msbs = uval >> k;
total_bits = 1 + k + msbs;
pattern = 1 << k; /* the unary end bit */
pattern |= (uval & ((1u<<k)-1)); /* the binary LSBs */
if(total_bits <= 32) {
if(!FLAC__bitwriter_write_raw_uint32(bw, pattern, total_bits))
return false;
}
else {
/* write the unary MSBs */
if(!FLAC__bitwriter_write_zeroes(bw, msbs))
return false;
/* write the unary end bit and binary LSBs */
if(!FLAC__bitwriter_write_raw_uint32(bw, pattern, k+1))
return false;
}
}
else {
unsigned q, r, d;
d = (1 << (k+1)) - parameter;
q = uval / parameter;
r = uval - (q * parameter);
/* write the unary MSBs */
if(!FLAC__bitwriter_write_zeroes(bw, q))
return false;
/* write the unary end bit */
if(!FLAC__bitwriter_write_raw_uint32(bw, 1, 1))
return false;
/* write the binary LSBs */
if(r >= d) {
if(!FLAC__bitwriter_write_raw_uint32(bw, r+d, k+1))
return false;
}
else {
if(!FLAC__bitwriter_write_raw_uint32(bw, r, k))
return false;
}
}
return true;
}
FLAC__bool FLAC__bitwriter_write_golomb_unsigned(FLAC__BitWriter *bw, unsigned uval, unsigned parameter)
{
unsigned total_bits, msbs;
unsigned k;
FLAC__ASSERT(0 != bw);
FLAC__ASSERT(0 != bw->buffer);
FLAC__ASSERT(parameter > 0);
k = FLAC__bitmath_ilog2(parameter);
if(parameter == 1u<<k) {
unsigned pattern;
FLAC__ASSERT(k <= 30);
msbs = uval >> k;
total_bits = 1 + k + msbs;
pattern = 1 << k; /* the unary end bit */
pattern |= (uval & ((1u<<k)-1)); /* the binary LSBs */
if(total_bits <= 32) {
if(!FLAC__bitwriter_write_raw_uint32(bw, pattern, total_bits))
return false;
}
else {
/* write the unary MSBs */
if(!FLAC__bitwriter_write_zeroes(bw, msbs))
return false;
/* write the unary end bit and binary LSBs */
if(!FLAC__bitwriter_write_raw_uint32(bw, pattern, k+1))
return false;
}
}
else {
unsigned q, r, d;
d = (1 << (k+1)) - parameter;
q = uval / parameter;
r = uval - (q * parameter);
/* write the unary MSBs */
if(!FLAC__bitwriter_write_zeroes(bw, q))
return false;
/* write the unary end bit */
if(!FLAC__bitwriter_write_raw_uint32(bw, 1, 1))
return false;
/* write the binary LSBs */
if(r >= d) {
if(!FLAC__bitwriter_write_raw_uint32(bw, r+d, k+1))
return false;
}
else {
if(!FLAC__bitwriter_write_raw_uint32(bw, r, k))
return false;
}
}
return true;
}
#endif /* UNUSED */
FLAC__bool FLAC__bitwriter_write_utf8_uint32(FLAC__BitWriter *bw, FLAC__uint32 val)
{
FLAC__bool ok = 1;
FLAC__ASSERT(0 != bw);
FLAC__ASSERT(0 != bw->buffer);
FLAC__ASSERT(!(val & 0x80000000)); /* this version only handles 31 bits */
if(val < 0x80) {
return FLAC__bitwriter_write_raw_uint32(bw, val, 8);
}
else if(val < 0x800) {
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0xC0 | (val>>6), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (val&0x3F), 8);
}
else if(val < 0x10000) {
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0xE0 | (val>>12), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | ((val>>6)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (val&0x3F), 8);
}
else if(val < 0x200000) {
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0xF0 | (val>>18), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | ((val>>12)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | ((val>>6)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (val&0x3F), 8);
}
else if(val < 0x4000000) {
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0xF8 | (val>>24), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | ((val>>18)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | ((val>>12)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | ((val>>6)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (val&0x3F), 8);
}
else {
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0xFC | (val>>30), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | ((val>>24)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | ((val>>18)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | ((val>>12)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | ((val>>6)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (val&0x3F), 8);
}
return ok;
}
FLAC__bool FLAC__bitwriter_write_utf8_uint64(FLAC__BitWriter *bw, FLAC__uint64 val)
{
FLAC__bool ok = 1;
FLAC__ASSERT(0 != bw);
FLAC__ASSERT(0 != bw->buffer);
FLAC__ASSERT(!(val & FLAC__U64L(0xFFFFFFF000000000))); /* this version only handles 36 bits */
if(val < 0x80) {
return FLAC__bitwriter_write_raw_uint32(bw, (FLAC__uint32)val, 8);
}
else if(val < 0x800) {
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0xC0 | (FLAC__uint32)(val>>6), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)(val&0x3F), 8);
}
else if(val < 0x10000) {
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0xE0 | (FLAC__uint32)(val>>12), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>6)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)(val&0x3F), 8);
}
else if(val < 0x200000) {
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0xF0 | (FLAC__uint32)(val>>18), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>12)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>6)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)(val&0x3F), 8);
}
else if(val < 0x4000000) {
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0xF8 | (FLAC__uint32)(val>>24), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>18)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>12)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>6)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)(val&0x3F), 8);
}
else if(val < 0x80000000) {
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0xFC | (FLAC__uint32)(val>>30), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>24)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>18)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>12)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>6)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)(val&0x3F), 8);
}
else {
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0xFE, 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>30)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>24)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>18)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>12)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)((val>>6)&0x3F), 8);
ok &= FLAC__bitwriter_write_raw_uint32(bw, 0x80 | (FLAC__uint32)(val&0x3F), 8);
}
return ok;
}
FLAC__bool FLAC__bitwriter_zero_pad_to_byte_boundary(FLAC__BitWriter *bw)
{
/* 0-pad to byte boundary */
if(bw->bits & 7u)
return FLAC__bitwriter_write_zeroes(bw, 8 - (bw->bits & 7u));
else
return true;
}
/* These functions are declared inline in this file but are also callable as
* externs from elsewhere.
* According to the C99 spec, section 6.7.4, simply providing a function
* prototype in a header file without 'inline' and making the function inline
* in this file should be sufficient.
* Unfortunately, the Microsoft VS compiler doesn't pick them up externally. To
* fix that we add extern declarations here.
*/
extern FLAC__bool FLAC__bitwriter_write_zeroes(FLAC__BitWriter *bw, unsigned bits);
extern FLAC__bool FLAC__bitwriter_write_raw_int32(FLAC__BitWriter *bw, FLAC__int32 val, unsigned bits);
extern FLAC__bool FLAC__bitwriter_write_raw_uint64(FLAC__BitWriter *bw, FLAC__uint64 val, unsigned bits);
extern FLAC__bool FLAC__bitwriter_write_raw_uint32_little_endian(FLAC__BitWriter *bw, FLAC__uint32 val);
extern FLAC__bool FLAC__bitwriter_write_byte_block(FLAC__BitWriter *bw, const FLAC__byte vals[], unsigned nvals);