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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-09-05 13:14:37 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-09-05 13:14:37 +0000
commitfd3b2704efc2b206784615c1a23eb25501842259 (patch)
tree61ba3a8af2a0ae2ac9ec362bbf18b038f5dc0448 /src/libFLAC/bitreader.c
parentInitial commit. (diff)
downloadflac-upstream.tar.xz
flac-upstream.zip
Adding upstream version 1.4.3+ds.upstream/1.4.3+dsupstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--src/libFLAC/bitreader.c1052
1 files changed, 1052 insertions, 0 deletions
diff --git a/src/libFLAC/bitreader.c b/src/libFLAC/bitreader.c
new file mode 100644
index 0000000..829b308
--- /dev/null
+++ b/src/libFLAC/bitreader.c
@@ -0,0 +1,1052 @@
+/* libFLAC - Free Lossless Audio Codec library
+ * Copyright (C) 2000-2009 Josh Coalson
+ * Copyright (C) 2011-2023 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/bitmath.h"
+#include "private/bitreader.h"
+#include "private/crc.h"
+#include "private/cpu.h"
+#include "private/macros.h"
+#include "FLAC/assert.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 COUNT_ZERO_MSBS2 below to match */
+/* WATCHOUT: there are a few places where the code will not work unless brword is >= 32 bits wide */
+/* also, some sections currently only have fast versions for 4 or 8 bytes per word */
+
+#if (ENABLE_64_BIT_WORDS == 0)
+
+typedef FLAC__uint32 brword;
+#define FLAC__BYTES_PER_WORD 4 /* sizeof brword */
+#define FLAC__BITS_PER_WORD 32
+#define FLAC__WORD_ALL_ONES ((FLAC__uint32)0xffffffff)
+/* SWAP_BE_WORD_TO_HOST swaps bytes in a brword (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
+/* counts the # of zero MSBs in a word */
+#define COUNT_ZERO_MSBS(word) FLAC__clz_uint32(word)
+#define COUNT_ZERO_MSBS2(word) FLAC__clz2_uint32(word)
+
+#else
+
+typedef FLAC__uint64 brword;
+#define FLAC__BYTES_PER_WORD 8 /* sizeof brword */
+#define FLAC__BITS_PER_WORD 64
+#define FLAC__WORD_ALL_ONES ((FLAC__uint64)FLAC__U64L(0xffffffffffffffff))
+/* SWAP_BE_WORD_TO_HOST swaps bytes in a brword (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_64(x)
+#endif
+/* counts the # of zero MSBs in a word */
+#define COUNT_ZERO_MSBS(word) FLAC__clz_uint64(word)
+#define COUNT_ZERO_MSBS2(word) FLAC__clz2_uint64(word)
+
+#endif
+
+/*
+ * This should be at least twice as large as the largest number of words
+ * required to represent any 'number' (in any encoding) you are going to
+ * read. With FLAC this is on the order of maybe a few hundred bits.
+ * If the buffer is smaller than that, the decoder won't be able to read
+ * in a whole number that is in a variable length encoding (e.g. Rice).
+ * But to be practical it should be at least 1K bytes.
+ *
+ * Increase this number to decrease the number of read callbacks, at the
+ * expense of using more memory. Or decrease for the reverse effect,
+ * keeping in mind the limit from the first paragraph. The optimal size
+ * also depends on the CPU cache size and other factors; some twiddling
+ * may be necessary to squeeze out the best performance.
+ */
+static const uint32_t FLAC__BITREADER_DEFAULT_CAPACITY = 65536u / FLAC__BITS_PER_WORD; /* in words */
+
+struct FLAC__BitReader {
+ /* any partially-consumed word at the head will stay right-justified as bits are consumed from the left */
+ /* any incomplete word at the tail will be left-justified, and bytes from the read callback are added on the right */
+ brword *buffer;
+ uint32_t capacity; /* in words */
+ uint32_t words; /* # of completed words in buffer */
+ uint32_t bytes; /* # of bytes in incomplete word at buffer[words] */
+ uint32_t consumed_words; /* #words ... */
+ uint32_t consumed_bits; /* ... + (#bits of head word) already consumed from the front of buffer */
+ uint32_t read_crc16; /* the running frame CRC */
+ uint32_t crc16_offset; /* the number of words in the current buffer that should not be CRC'd */
+ uint32_t crc16_align; /* the number of bits in the current consumed word that should not be CRC'd */
+ FLAC__bool read_limit_set; /* whether reads are limited */
+ uint32_t read_limit; /* the remaining size of what can be read */
+ uint32_t last_seen_framesync; /* the location of the last seen framesync, if it is in the buffer, in bits from front of buffer */
+ FLAC__BitReaderReadCallback read_callback;
+ void *client_data;
+};
+
+static inline void crc16_update_word_(FLAC__BitReader *br, brword word)
+{
+ register uint32_t crc = br->read_crc16;
+
+ for ( ; br->crc16_align < FLAC__BITS_PER_WORD ; br->crc16_align += 8) {
+ uint32_t shift = FLAC__BITS_PER_WORD - 8 - br->crc16_align ;
+ crc = FLAC__CRC16_UPDATE ((uint32_t) (shift < FLAC__BITS_PER_WORD ? (word >> shift) & 0xff : 0), crc);
+ }
+
+ br->read_crc16 = crc;
+ br->crc16_align = 0;
+}
+
+static inline void crc16_update_block_(FLAC__BitReader *br)
+{
+ if(br->consumed_words > br->crc16_offset && br->crc16_align)
+ crc16_update_word_(br, br->buffer[br->crc16_offset++]);
+
+ /* Prevent OOB read due to wrap-around. */
+ if (br->consumed_words > br->crc16_offset) {
+#if FLAC__BYTES_PER_WORD == 4
+ br->read_crc16 = FLAC__crc16_update_words32(br->buffer + br->crc16_offset, br->consumed_words - br->crc16_offset, br->read_crc16);
+#elif FLAC__BYTES_PER_WORD == 8
+ br->read_crc16 = FLAC__crc16_update_words64(br->buffer + br->crc16_offset, br->consumed_words - br->crc16_offset, br->read_crc16);
+#else
+ unsigned i;
+
+ for (i = br->crc16_offset; i < br->consumed_words; i++)
+ crc16_update_word_(br, br->buffer[i]);
+#endif
+ }
+
+ br->crc16_offset = 0;
+}
+
+static FLAC__bool bitreader_read_from_client_(FLAC__BitReader *br)
+{
+ uint32_t start, end;
+ size_t bytes;
+ FLAC__byte *target;
+#if WORDS_BIGENDIAN
+#else
+ brword preswap_backup;
+#endif
+
+ /* first shift the unconsumed buffer data toward the front as much as possible */
+ if(br->consumed_words > 0) {
+ /* invalidate last seen framesync */
+ br->last_seen_framesync = -1;
+
+ crc16_update_block_(br); /* CRC consumed words */
+
+ start = br->consumed_words;
+ end = br->words + (br->bytes? 1:0);
+ memmove(br->buffer, br->buffer+start, FLAC__BYTES_PER_WORD * (end - start));
+
+ br->words -= start;
+ br->consumed_words = 0;
+ }
+
+ /*
+ * set the target for reading, taking into account word alignment and endianness
+ */
+ bytes = (br->capacity - br->words) * FLAC__BYTES_PER_WORD - br->bytes;
+ if(bytes == 0)
+ return false; /* no space left, buffer is too small; see note for FLAC__BITREADER_DEFAULT_CAPACITY */
+ target = ((FLAC__byte*)(br->buffer+br->words)) + br->bytes;
+
+ /* before reading, if the existing reader looks like this (say brword is 32 bits wide)
+ * bitstream : 11 22 33 44 55 br->words=1 br->bytes=1 (partial tail word is left-justified)
+ * buffer[BE]: 11 22 33 44 55 ?? ?? ?? (shown laid out as bytes sequentially in memory)
+ * buffer[LE]: 44 33 22 11 ?? ?? ?? 55 (?? being don't-care)
+ * ^^-------target, bytes=3
+ * on LE machines, have to byteswap the odd tail word so nothing is
+ * overwritten:
+ */
+#if WORDS_BIGENDIAN
+#else
+ preswap_backup = br->buffer[br->words];
+ if(br->bytes)
+ br->buffer[br->words] = SWAP_BE_WORD_TO_HOST(br->buffer[br->words]);
+#endif
+
+ /* now it looks like:
+ * bitstream : 11 22 33 44 55 br->words=1 br->bytes=1
+ * buffer[BE]: 11 22 33 44 55 ?? ?? ??
+ * buffer[LE]: 44 33 22 11 55 ?? ?? ??
+ * ^^-------target, bytes=3
+ */
+
+ /* read in the data; note that the callback may return a smaller number of bytes */
+ if(!br->read_callback(target, &bytes, br->client_data)){
+ /* Despite the read callback failing, the data in the target
+ * might be used later, when the buffer is rewound. Therefore
+ * we revert the swap that was just done */
+#if WORDS_BIGENDIAN
+#else
+ br->buffer[br->words] = preswap_backup;
+#endif
+ return false;
+ }
+
+ /* after reading bytes 66 77 88 99 AA BB CC DD EE FF from the client:
+ * bitstream : 11 22 33 44 55 66 77 88 99 AA BB CC DD EE FF
+ * buffer[BE]: 11 22 33 44 55 66 77 88 99 AA BB CC DD EE FF ??
+ * buffer[LE]: 44 33 22 11 55 66 77 88 99 AA BB CC DD EE FF ??
+ * now have to byteswap on LE machines:
+ */
+#if WORDS_BIGENDIAN
+#else
+ end = (br->words*FLAC__BYTES_PER_WORD + br->bytes + (uint32_t)bytes + (FLAC__BYTES_PER_WORD-1)) / FLAC__BYTES_PER_WORD;
+ for(start = br->words; start < end; start++)
+ br->buffer[start] = SWAP_BE_WORD_TO_HOST(br->buffer[start]);
+#endif
+
+ /* now it looks like:
+ * bitstream : 11 22 33 44 55 66 77 88 99 AA BB CC DD EE FF
+ * buffer[BE]: 11 22 33 44 55 66 77 88 99 AA BB CC DD EE FF ??
+ * buffer[LE]: 44 33 22 11 88 77 66 55 CC BB AA 99 ?? FF EE DD
+ * finally we'll update the reader values:
+ */
+ end = br->words*FLAC__BYTES_PER_WORD + br->bytes + (uint32_t)bytes;
+ br->words = end / FLAC__BYTES_PER_WORD;
+ br->bytes = end % FLAC__BYTES_PER_WORD;
+
+ return true;
+}
+
+/***********************************************************************
+ *
+ * Class constructor/destructor
+ *
+ ***********************************************************************/
+
+FLAC__BitReader *FLAC__bitreader_new(void)
+{
+ FLAC__BitReader *br = calloc(1, sizeof(FLAC__BitReader));
+
+ /* calloc() implies:
+ memset(br, 0, sizeof(FLAC__BitReader));
+ br->buffer = 0;
+ br->capacity = 0;
+ br->words = br->bytes = 0;
+ br->consumed_words = br->consumed_bits = 0;
+ br->read_callback = 0;
+ br->client_data = 0;
+ */
+ return br;
+}
+
+void FLAC__bitreader_delete(FLAC__BitReader *br)
+{
+ FLAC__ASSERT(0 != br);
+
+ FLAC__bitreader_free(br);
+ free(br);
+}
+
+/***********************************************************************
+ *
+ * Public class methods
+ *
+ ***********************************************************************/
+
+FLAC__bool FLAC__bitreader_init(FLAC__BitReader *br, FLAC__BitReaderReadCallback rcb, void *cd)
+{
+ FLAC__ASSERT(0 != br);
+
+ br->words = br->bytes = 0;
+ br->consumed_words = br->consumed_bits = 0;
+ br->capacity = FLAC__BITREADER_DEFAULT_CAPACITY;
+ br->buffer = malloc(sizeof(brword) * br->capacity);
+ if(br->buffer == 0)
+ return false;
+ br->read_callback = rcb;
+ br->client_data = cd;
+ br->read_limit_set = false;
+ br->read_limit = -1;
+ br->last_seen_framesync = -1;
+
+ return true;
+}
+
+void FLAC__bitreader_free(FLAC__BitReader *br)
+{
+ FLAC__ASSERT(0 != br);
+
+ if(0 != br->buffer)
+ free(br->buffer);
+ br->buffer = 0;
+ br->capacity = 0;
+ br->words = br->bytes = 0;
+ br->consumed_words = br->consumed_bits = 0;
+ br->read_callback = 0;
+ br->client_data = 0;
+ br->read_limit_set = false;
+ br->read_limit = -1;
+ br->last_seen_framesync = -1;
+}
+
+FLAC__bool FLAC__bitreader_clear(FLAC__BitReader *br)
+{
+ br->words = br->bytes = 0;
+ br->consumed_words = br->consumed_bits = 0;
+ br->read_limit_set = false;
+ br->read_limit = -1;
+ br->last_seen_framesync = -1;
+ return true;
+}
+
+void FLAC__bitreader_set_framesync_location(FLAC__BitReader *br)
+{
+ br->last_seen_framesync = br->consumed_words * FLAC__BYTES_PER_WORD + br->consumed_bits / 8;
+}
+
+FLAC__bool FLAC__bitreader_rewind_to_after_last_seen_framesync(FLAC__BitReader *br)
+{
+ if(br->last_seen_framesync == (uint32_t)-1) {
+ br->consumed_words = br->consumed_bits = 0;
+ return false;
+ }
+ else {
+ br->consumed_words = (br->last_seen_framesync + 1) / FLAC__BYTES_PER_WORD;
+ br->consumed_bits = ((br->last_seen_framesync + 1) % FLAC__BYTES_PER_WORD) * 8;
+ return true;
+ }
+}
+
+void FLAC__bitreader_reset_read_crc16(FLAC__BitReader *br, FLAC__uint16 seed)
+{
+ FLAC__ASSERT(0 != br);
+ FLAC__ASSERT(0 != br->buffer);
+ FLAC__ASSERT((br->consumed_bits & 7) == 0);
+
+ br->read_crc16 = (uint32_t)seed;
+ br->crc16_offset = br->consumed_words;
+ br->crc16_align = br->consumed_bits;
+}
+
+FLAC__uint16 FLAC__bitreader_get_read_crc16(FLAC__BitReader *br)
+{
+ FLAC__ASSERT(0 != br);
+ FLAC__ASSERT(0 != br->buffer);
+
+ /* CRC consumed words up to here */
+ crc16_update_block_(br);
+
+ FLAC__ASSERT((br->consumed_bits & 7) == 0);
+ FLAC__ASSERT(br->crc16_align <= br->consumed_bits);
+
+ /* CRC any tail bytes in a partially-consumed word */
+ if(br->consumed_bits) {
+ const brword tail = br->buffer[br->consumed_words];
+ for( ; br->crc16_align < br->consumed_bits; br->crc16_align += 8)
+ br->read_crc16 = FLAC__CRC16_UPDATE((uint32_t)((tail >> (FLAC__BITS_PER_WORD-8-br->crc16_align)) & 0xff), br->read_crc16);
+ }
+ return br->read_crc16;
+}
+
+inline FLAC__bool FLAC__bitreader_is_consumed_byte_aligned(const FLAC__BitReader *br)
+{
+ return ((br->consumed_bits & 7) == 0);
+}
+
+inline uint32_t FLAC__bitreader_bits_left_for_byte_alignment(const FLAC__BitReader *br)
+{
+ return 8 - (br->consumed_bits & 7);
+}
+
+inline uint32_t FLAC__bitreader_get_input_bits_unconsumed(const FLAC__BitReader *br)
+{
+ return (br->words-br->consumed_words)*FLAC__BITS_PER_WORD + br->bytes*8 - br->consumed_bits;
+}
+
+void FLAC__bitreader_set_limit(FLAC__BitReader *br, uint32_t limit)
+{
+ br->read_limit = limit;
+ br->read_limit_set = true;
+}
+
+void FLAC__bitreader_remove_limit(FLAC__BitReader *br)
+{
+ br->read_limit_set = false;
+ br->read_limit = -1;
+}
+
+uint32_t FLAC__bitreader_limit_remaining(FLAC__BitReader *br)
+{
+ FLAC__ASSERT(br->read_limit_set);
+ return br->read_limit;
+}
+void FLAC__bitreader_limit_invalidate(FLAC__BitReader *br)
+{
+ br->read_limit = -1;
+}
+
+FLAC__bool FLAC__bitreader_read_raw_uint32(FLAC__BitReader *br, FLAC__uint32 *val, uint32_t bits)
+{
+ FLAC__ASSERT(0 != br);
+ FLAC__ASSERT(0 != br->buffer);
+
+ FLAC__ASSERT(bits <= 32);
+ FLAC__ASSERT((br->capacity*FLAC__BITS_PER_WORD) * 2 >= bits);
+ FLAC__ASSERT(br->consumed_words <= br->words);
+
+ /* WATCHOUT: code does not work with <32bit words; we can make things much faster with this assertion */
+ FLAC__ASSERT(FLAC__BITS_PER_WORD >= 32);
+
+ if(bits == 0) { /* OPT: investigate if this can ever happen, maybe change to assertion */
+ *val = 0;
+ return true;
+ }
+
+ if(br->read_limit_set && br->read_limit < (uint32_t)-1){
+ if(br->read_limit < bits) {
+ br->read_limit = -1;
+ return false;
+ }
+ else
+ br->read_limit -= bits;
+ }
+
+ while((br->words-br->consumed_words)*FLAC__BITS_PER_WORD + br->bytes*8 - br->consumed_bits < bits) {
+ if(!bitreader_read_from_client_(br))
+ return false;
+ }
+ if(br->consumed_words < br->words) { /* if we've not consumed up to a partial tail word... */
+ /* OPT: taking out the consumed_bits==0 "else" case below might make things faster if less code allows the compiler to inline this function */
+ if(br->consumed_bits) {
+ /* this also works when consumed_bits==0, it's just a little slower than necessary for that case */
+ const uint32_t n = FLAC__BITS_PER_WORD - br->consumed_bits;
+ const brword word = br->buffer[br->consumed_words];
+ const brword mask = br->consumed_bits < FLAC__BITS_PER_WORD ? FLAC__WORD_ALL_ONES >> br->consumed_bits : 0;
+ if(bits < n) {
+ uint32_t shift = n - bits;
+ *val = shift < FLAC__BITS_PER_WORD ? (FLAC__uint32)((word & mask) >> shift) : 0; /* The result has <= 32 non-zero bits */
+ br->consumed_bits += bits;
+ return true;
+ }
+ /* (FLAC__BITS_PER_WORD - br->consumed_bits <= bits) ==> (FLAC__WORD_ALL_ONES >> br->consumed_bits) has no more than 'bits' non-zero bits */
+ *val = (FLAC__uint32)(word & mask);
+ bits -= n;
+ br->consumed_words++;
+ br->consumed_bits = 0;
+ if(bits) { /* if there are still bits left to read, there have to be less than 32 so they will all be in the next word */
+ uint32_t shift = FLAC__BITS_PER_WORD - bits;
+ *val = bits < 32 ? *val << bits : 0;
+ *val |= shift < FLAC__BITS_PER_WORD ? (FLAC__uint32)(br->buffer[br->consumed_words] >> shift) : 0;
+ br->consumed_bits = bits;
+ }
+ return true;
+ }
+ else { /* br->consumed_bits == 0 */
+ const brword word = br->buffer[br->consumed_words];
+ if(bits < FLAC__BITS_PER_WORD) {
+ *val = (FLAC__uint32)(word >> (FLAC__BITS_PER_WORD-bits));
+ br->consumed_bits = bits;
+ return true;
+ }
+ /* at this point bits == FLAC__BITS_PER_WORD == 32; because of previous assertions, it can't be larger */
+ *val = (FLAC__uint32)word;
+ br->consumed_words++;
+ return true;
+ }
+ }
+ else {
+ /* in this case we're starting our read at a partial tail word;
+ * the reader has guaranteed that we have at least 'bits' bits
+ * available to read, which makes this case simpler.
+ */
+ /* OPT: taking out the consumed_bits==0 "else" case below might make things faster if less code allows the compiler to inline this function */
+ if(br->consumed_bits) {
+ /* this also works when consumed_bits==0, it's just a little slower than necessary for that case */
+ FLAC__ASSERT(br->consumed_bits + bits <= br->bytes*8);
+ *val = (FLAC__uint32)((br->buffer[br->consumed_words] & (FLAC__WORD_ALL_ONES >> br->consumed_bits)) >> (FLAC__BITS_PER_WORD-br->consumed_bits-bits));
+ br->consumed_bits += bits;
+ return true;
+ }
+ else {
+ *val = (FLAC__uint32)(br->buffer[br->consumed_words] >> (FLAC__BITS_PER_WORD-bits));
+ br->consumed_bits += bits;
+ return true;
+ }
+ }
+}
+
+FLAC__bool FLAC__bitreader_read_raw_int32(FLAC__BitReader *br, FLAC__int32 *val, uint32_t bits)
+{
+ FLAC__uint32 uval, mask;
+ /* OPT: inline raw uint32 code here, or make into a macro if possible in the .h file */
+ if (bits < 1 || ! FLAC__bitreader_read_raw_uint32(br, &uval, bits))
+ return false;
+ /* sign-extend *val assuming it is currently bits wide. */
+ /* From: https://graphics.stanford.edu/~seander/bithacks.html#FixedSignExtend */
+ mask = bits >= 33 ? 0 : 1lu << (bits - 1);
+ *val = (uval ^ mask) - mask;
+ return true;
+}
+
+FLAC__bool FLAC__bitreader_read_raw_uint64(FLAC__BitReader *br, FLAC__uint64 *val, uint32_t bits)
+{
+ FLAC__uint32 hi, lo;
+
+ if(bits > 32) {
+ if(!FLAC__bitreader_read_raw_uint32(br, &hi, bits-32))
+ return false;
+ if(!FLAC__bitreader_read_raw_uint32(br, &lo, 32))
+ return false;
+ *val = hi;
+ *val <<= 32;
+ *val |= lo;
+ }
+ else {
+ if(!FLAC__bitreader_read_raw_uint32(br, &lo, bits))
+ return false;
+ *val = lo;
+ }
+ return true;
+}
+
+FLAC__bool FLAC__bitreader_read_raw_int64(FLAC__BitReader *br, FLAC__int64 *val, uint32_t bits)
+{
+ FLAC__uint64 uval, mask;
+ /* OPT: inline raw uint64 code here, or make into a macro if possible in the .h file */
+ if (bits < 1 || ! FLAC__bitreader_read_raw_uint64(br, &uval, bits))
+ return false;
+ /* sign-extend *val assuming it is currently bits wide. */
+ /* From: https://graphics.stanford.edu/~seander/bithacks.html#FixedSignExtend */
+ mask = bits >= 65 ? 0 : 1llu << (bits - 1);
+ *val = (uval ^ mask) - mask;
+ return true;
+}
+
+inline FLAC__bool FLAC__bitreader_read_uint32_little_endian(FLAC__BitReader *br, FLAC__uint32 *val)
+{
+ FLAC__uint32 x8, x32 = 0;
+
+ /* this doesn't need to be that fast as currently it is only used for vorbis comments */
+
+ if(!FLAC__bitreader_read_raw_uint32(br, &x32, 8))
+ return false;
+
+ if(!FLAC__bitreader_read_raw_uint32(br, &x8, 8))
+ return false;
+ x32 |= (x8 << 8);
+
+ if(!FLAC__bitreader_read_raw_uint32(br, &x8, 8))
+ return false;
+ x32 |= (x8 << 16);
+
+ if(!FLAC__bitreader_read_raw_uint32(br, &x8, 8))
+ return false;
+ x32 |= (x8 << 24);
+
+ *val = x32;
+ return true;
+}
+
+FLAC__bool FLAC__bitreader_skip_bits_no_crc(FLAC__BitReader *br, uint32_t bits)
+{
+ /*
+ * OPT: a faster implementation is possible but probably not that useful
+ * since this is only called a couple of times in the metadata readers.
+ */
+ FLAC__ASSERT(0 != br);
+ FLAC__ASSERT(0 != br->buffer);
+
+ if(bits > 0) {
+ const uint32_t n = br->consumed_bits & 7;
+ uint32_t m;
+ FLAC__uint32 x;
+
+ if(n != 0) {
+ m = flac_min(8-n, bits);
+ if(!FLAC__bitreader_read_raw_uint32(br, &x, m))
+ return false;
+ bits -= m;
+ }
+ m = bits / 8;
+ if(m > 0) {
+ if(!FLAC__bitreader_skip_byte_block_aligned_no_crc(br, m))
+ return false;
+ bits %= 8;
+ }
+ if(bits > 0) {
+ if(!FLAC__bitreader_read_raw_uint32(br, &x, bits))
+ return false;
+ }
+ }
+
+ return true;
+}
+
+FLAC__bool FLAC__bitreader_skip_byte_block_aligned_no_crc(FLAC__BitReader *br, uint32_t nvals)
+{
+ FLAC__uint32 x;
+
+ FLAC__ASSERT(0 != br);
+ FLAC__ASSERT(0 != br->buffer);
+ FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(br));
+
+ if(br->read_limit_set && br->read_limit < (uint32_t)-1){
+ if(br->read_limit < nvals*8){
+ br->read_limit = -1;
+ return false;
+ }
+ }
+
+ /* step 1: skip over partial head word to get word aligned */
+ while(nvals && br->consumed_bits) { /* i.e. run until we read 'nvals' bytes or we hit the end of the head word */
+ if(!FLAC__bitreader_read_raw_uint32(br, &x, 8))
+ return false;
+ nvals--;
+ }
+ if(0 == nvals)
+ return true;
+
+ /* step 2: skip whole words in chunks */
+ while(nvals >= FLAC__BYTES_PER_WORD) {
+ if(br->consumed_words < br->words) {
+ br->consumed_words++;
+ nvals -= FLAC__BYTES_PER_WORD;
+ if(br->read_limit_set)
+ br->read_limit -= FLAC__BITS_PER_WORD;
+ }
+ else if(!bitreader_read_from_client_(br))
+ return false;
+ }
+ /* step 3: skip any remainder from partial tail bytes */
+ while(nvals) {
+ if(!FLAC__bitreader_read_raw_uint32(br, &x, 8))
+ return false;
+ nvals--;
+ }
+
+ return true;
+}
+
+FLAC__bool FLAC__bitreader_read_byte_block_aligned_no_crc(FLAC__BitReader *br, FLAC__byte *val, uint32_t nvals)
+{
+ FLAC__uint32 x;
+
+ FLAC__ASSERT(0 != br);
+ FLAC__ASSERT(0 != br->buffer);
+ FLAC__ASSERT(FLAC__bitreader_is_consumed_byte_aligned(br));
+
+ if(br->read_limit_set && br->read_limit < (uint32_t)-1){
+ if(br->read_limit < nvals*8){
+ br->read_limit = -1;
+ return false;
+ }
+ }
+
+ /* step 1: read from partial head word to get word aligned */
+ while(nvals && br->consumed_bits) { /* i.e. run until we read 'nvals' bytes or we hit the end of the head word */
+ if(!FLAC__bitreader_read_raw_uint32(br, &x, 8))
+ return false;
+ *val++ = (FLAC__byte)x;
+ nvals--;
+ }
+ if(0 == nvals)
+ return true;
+ /* step 2: read whole words in chunks */
+ while(nvals >= FLAC__BYTES_PER_WORD) {
+ if(br->consumed_words < br->words) {
+ const brword word = br->buffer[br->consumed_words++];
+#if FLAC__BYTES_PER_WORD == 4
+ val[0] = (FLAC__byte)(word >> 24);
+ val[1] = (FLAC__byte)(word >> 16);
+ val[2] = (FLAC__byte)(word >> 8);
+ val[3] = (FLAC__byte)word;
+#elif FLAC__BYTES_PER_WORD == 8
+ val[0] = (FLAC__byte)(word >> 56);
+ val[1] = (FLAC__byte)(word >> 48);
+ val[2] = (FLAC__byte)(word >> 40);
+ val[3] = (FLAC__byte)(word >> 32);
+ val[4] = (FLAC__byte)(word >> 24);
+ val[5] = (FLAC__byte)(word >> 16);
+ val[6] = (FLAC__byte)(word >> 8);
+ val[7] = (FLAC__byte)word;
+#else
+ for(x = 0; x < FLAC__BYTES_PER_WORD; x++)
+ val[x] = (FLAC__byte)(word >> (8*(FLAC__BYTES_PER_WORD-x-1)));
+#endif
+ val += FLAC__BYTES_PER_WORD;
+ nvals -= FLAC__BYTES_PER_WORD;
+ if(br->read_limit_set)
+ br->read_limit -= FLAC__BITS_PER_WORD;
+ }
+ else if(!bitreader_read_from_client_(br))
+ return false;
+ }
+ /* step 3: read any remainder from partial tail bytes */
+ while(nvals) {
+ if(!FLAC__bitreader_read_raw_uint32(br, &x, 8))
+ return false;
+ *val++ = (FLAC__byte)x;
+ nvals--;
+ }
+
+ return true;
+}
+
+FLAC__bool FLAC__bitreader_read_unary_unsigned(FLAC__BitReader *br, uint32_t *val)
+#if 0 /* slow but readable version */
+{
+ uint32_t bit;
+
+ FLAC__ASSERT(0 != br);
+ FLAC__ASSERT(0 != br->buffer);
+
+ *val = 0;
+ while(1) {
+ if(!FLAC__bitreader_read_bit(br, &bit))
+ return false;
+ if(bit)
+ break;
+ else
+ *val++;
+ }
+ return true;
+}
+#else
+{
+ uint32_t i;
+
+ FLAC__ASSERT(0 != br);
+ FLAC__ASSERT(0 != br->buffer);
+
+ *val = 0;
+ while(1) {
+ while(br->consumed_words < br->words) { /* if we've not consumed up to a partial tail word... */
+ brword b = br->consumed_bits < FLAC__BITS_PER_WORD ? br->buffer[br->consumed_words] << br->consumed_bits : 0;
+ if(b) {
+ i = COUNT_ZERO_MSBS(b);
+ *val += i;
+ i++;
+ br->consumed_bits += i;
+ if(br->consumed_bits >= FLAC__BITS_PER_WORD) { /* faster way of testing if(br->consumed_bits == FLAC__BITS_PER_WORD) */
+ br->consumed_words++;
+ br->consumed_bits = 0;
+ }
+ return true;
+ }
+ else {
+ *val += FLAC__BITS_PER_WORD - br->consumed_bits;
+ br->consumed_words++;
+ br->consumed_bits = 0;
+ /* didn't find stop bit yet, have to keep going... */
+ }
+ }
+ /* at this point we've eaten up all the whole words; have to try
+ * reading through any tail bytes before calling the read callback.
+ * this is a repeat of the above logic adjusted for the fact we
+ * don't have a whole word. note though if the client is feeding
+ * us data a byte at a time (unlikely), br->consumed_bits may not
+ * be zero.
+ */
+ if(br->bytes*8 > br->consumed_bits) {
+ const uint32_t end = br->bytes * 8;
+ brword b = (br->buffer[br->consumed_words] & (FLAC__WORD_ALL_ONES << (FLAC__BITS_PER_WORD-end))) << br->consumed_bits;
+ if(b) {
+ i = COUNT_ZERO_MSBS(b);
+ *val += i;
+ i++;
+ br->consumed_bits += i;
+ FLAC__ASSERT(br->consumed_bits < FLAC__BITS_PER_WORD);
+ return true;
+ }
+ else {
+ *val += end - br->consumed_bits;
+ br->consumed_bits = end;
+ FLAC__ASSERT(br->consumed_bits < FLAC__BITS_PER_WORD);
+ /* didn't find stop bit yet, have to keep going... */
+ }
+ }
+ if(!bitreader_read_from_client_(br))
+ return false;
+ }
+}
+#endif
+
+#if 0 /* unused */
+FLAC__bool FLAC__bitreader_read_rice_signed(FLAC__BitReader *br, int *val, uint32_t parameter)
+{
+ FLAC__uint32 lsbs = 0, msbs = 0;
+ uint32_t uval;
+
+ FLAC__ASSERT(0 != br);
+ FLAC__ASSERT(0 != br->buffer);
+ FLAC__ASSERT(parameter <= 31);
+
+ /* read the unary MSBs and end bit */
+ if(!FLAC__bitreader_read_unary_unsigned(br, &msbs))
+ return false;
+
+ /* read the binary LSBs */
+ if(!FLAC__bitreader_read_raw_uint32(br, &lsbs, parameter))
+ return false;
+
+ /* compose the value */
+ uval = (msbs << parameter) | lsbs;
+ if(uval & 1)
+ *val = -((int)(uval >> 1)) - 1;
+ else
+ *val = (int)(uval >> 1);
+
+ return true;
+}
+#endif
+
+/* this is by far the most heavily used reader call. it ain't pretty but it's fast */
+FLAC__bool FLAC__bitreader_read_rice_signed_block(FLAC__BitReader *br, int vals[], uint32_t nvals, uint32_t parameter)
+#include "deduplication/bitreader_read_rice_signed_block.c"
+
+#ifdef FLAC__BMI2_SUPPORTED
+FLAC__SSE_TARGET("bmi2")
+FLAC__bool FLAC__bitreader_read_rice_signed_block_bmi2(FLAC__BitReader *br, int vals[], uint32_t nvals, uint32_t parameter)
+#include "deduplication/bitreader_read_rice_signed_block.c"
+#endif
+
+#if 0 /* UNUSED */
+FLAC__bool FLAC__bitreader_read_golomb_signed(FLAC__BitReader *br, int *val, uint32_t parameter)
+{
+ FLAC__uint32 lsbs = 0, msbs = 0;
+ uint32_t bit, uval, k;
+
+ FLAC__ASSERT(0 != br);
+ FLAC__ASSERT(0 != br->buffer);
+
+ k = FLAC__bitmath_ilog2(parameter);
+
+ /* read the unary MSBs and end bit */
+ if(!FLAC__bitreader_read_unary_unsigned(br, &msbs))
+ return false;
+
+ /* read the binary LSBs */
+ if(!FLAC__bitreader_read_raw_uint32(br, &lsbs, k))
+ return false;
+
+ if(parameter == 1u<<k) {
+ /* compose the value */
+ uval = (msbs << k) | lsbs;
+ }
+ else {
+ uint32_t d = (1 << (k+1)) - parameter;
+ if(lsbs >= d) {
+ if(!FLAC__bitreader_read_bit(br, &bit))
+ return false;
+ lsbs <<= 1;
+ lsbs |= bit;
+ lsbs -= d;
+ }
+ /* compose the value */
+ uval = msbs * parameter + lsbs;
+ }
+
+ /* unfold uint32_t to signed */
+ if(uval & 1)
+ *val = -((int)(uval >> 1)) - 1;
+ else
+ *val = (int)(uval >> 1);
+
+ return true;
+}
+
+FLAC__bool FLAC__bitreader_read_golomb_unsigned(FLAC__BitReader *br, uint32_t *val, uint32_t parameter)
+{
+ FLAC__uint32 lsbs, msbs = 0;
+ uint32_t bit, k;
+
+ FLAC__ASSERT(0 != br);
+ FLAC__ASSERT(0 != br->buffer);
+
+ k = FLAC__bitmath_ilog2(parameter);
+
+ /* read the unary MSBs and end bit */
+ if(!FLAC__bitreader_read_unary_unsigned(br, &msbs))
+ return false;
+
+ /* read the binary LSBs */
+ if(!FLAC__bitreader_read_raw_uint32(br, &lsbs, k))
+ return false;
+
+ if(parameter == 1u<<k) {
+ /* compose the value */
+ *val = (msbs << k) | lsbs;
+ }
+ else {
+ uint32_t d = (1 << (k+1)) - parameter;
+ if(lsbs >= d) {
+ if(!FLAC__bitreader_read_bit(br, &bit))
+ return false;
+ lsbs <<= 1;
+ lsbs |= bit;
+ lsbs -= d;
+ }
+ /* compose the value */
+ *val = msbs * parameter + lsbs;
+ }
+
+ return true;
+}
+#endif /* UNUSED */
+
+/* on return, if *val == 0xffffffff then the utf-8 sequence was invalid, but the return value will be true */
+FLAC__bool FLAC__bitreader_read_utf8_uint32(FLAC__BitReader *br, FLAC__uint32 *val, FLAC__byte *raw, uint32_t *rawlen)
+{
+ FLAC__uint32 v = 0;
+ FLAC__uint32 x;
+ uint32_t i;
+
+ if(!FLAC__bitreader_read_raw_uint32(br, &x, 8))
+ return false;
+ if(raw)
+ raw[(*rawlen)++] = (FLAC__byte)x;
+ if(!(x & 0x80)) { /* 0xxxxxxx */
+ v = x;
+ i = 0;
+ }
+ else if(x & 0xC0 && !(x & 0x20)) { /* 110xxxxx */
+ v = x & 0x1F;
+ i = 1;
+ }
+ else if(x & 0xE0 && !(x & 0x10)) { /* 1110xxxx */
+ v = x & 0x0F;
+ i = 2;
+ }
+ else if(x & 0xF0 && !(x & 0x08)) { /* 11110xxx */
+ v = x & 0x07;
+ i = 3;
+ }
+ else if(x & 0xF8 && !(x & 0x04)) { /* 111110xx */
+ v = x & 0x03;
+ i = 4;
+ }
+ else if(x & 0xFC && !(x & 0x02)) { /* 1111110x */
+ v = x & 0x01;
+ i = 5;
+ }
+ else {
+ *val = 0xffffffff;
+ return true;
+ }
+ for( ; i; i--) {
+ if(!FLAC__bitreader_read_raw_uint32(br, &x, 8))
+ return false;
+ if(raw)
+ raw[(*rawlen)++] = (FLAC__byte)x;
+ if(!(x & 0x80) || (x & 0x40)) { /* 10xxxxxx */
+ *val = 0xffffffff;
+ return true;
+ }
+ v <<= 6;
+ v |= (x & 0x3F);
+ }
+ *val = v;
+ return true;
+}
+
+/* on return, if *val == 0xffffffffffffffff then the utf-8 sequence was invalid, but the return value will be true */
+FLAC__bool FLAC__bitreader_read_utf8_uint64(FLAC__BitReader *br, FLAC__uint64 *val, FLAC__byte *raw, uint32_t *rawlen)
+{
+ FLAC__uint64 v = 0;
+ FLAC__uint32 x;
+ uint32_t i;
+
+ if(!FLAC__bitreader_read_raw_uint32(br, &x, 8))
+ return false;
+ if(raw)
+ raw[(*rawlen)++] = (FLAC__byte)x;
+ if(!(x & 0x80)) { /* 0xxxxxxx */
+ v = x;
+ i = 0;
+ }
+ else if(x & 0xC0 && !(x & 0x20)) { /* 110xxxxx */
+ v = x & 0x1F;
+ i = 1;
+ }
+ else if(x & 0xE0 && !(x & 0x10)) { /* 1110xxxx */
+ v = x & 0x0F;
+ i = 2;
+ }
+ else if(x & 0xF0 && !(x & 0x08)) { /* 11110xxx */
+ v = x & 0x07;
+ i = 3;
+ }
+ else if(x & 0xF8 && !(x & 0x04)) { /* 111110xx */
+ v = x & 0x03;
+ i = 4;
+ }
+ else if(x & 0xFC && !(x & 0x02)) { /* 1111110x */
+ v = x & 0x01;
+ i = 5;
+ }
+ else if(x & 0xFE && !(x & 0x01)) { /* 11111110 */
+ v = 0;
+ i = 6;
+ }
+ else {
+ *val = FLAC__U64L(0xffffffffffffffff);
+ return true;
+ }
+ for( ; i; i--) {
+ if(!FLAC__bitreader_read_raw_uint32(br, &x, 8))
+ return false;
+ if(raw)
+ raw[(*rawlen)++] = (FLAC__byte)x;
+ if(!(x & 0x80) || (x & 0x40)) { /* 10xxxxxx */
+ *val = FLAC__U64L(0xffffffffffffffff);
+ return true;
+ }
+ v <<= 6;
+ v |= (x & 0x3F);
+ }
+ *val = v;
+ 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__bitreader_is_consumed_byte_aligned(const FLAC__BitReader *br);
+extern uint32_t FLAC__bitreader_bits_left_for_byte_alignment(const FLAC__BitReader *br);
+extern uint32_t FLAC__bitreader_get_input_bits_unconsumed(const FLAC__BitReader *br);
+extern FLAC__bool FLAC__bitreader_read_uint32_little_endian(FLAC__BitReader *br, FLAC__uint32 *val);