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diff --git a/media/ffvpx/libavcodec/get_bits.h b/media/ffvpx/libavcodec/get_bits.h
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+/*
+ * Copyright (c) 2004 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+/**
+ * @file
+ * bitstream reader API header.
+ */
+
+#ifndef AVCODEC_GET_BITS_H
+#define AVCODEC_GET_BITS_H
+
+#include <stdint.h>
+
+#include "libavutil/common.h"
+#include "libavutil/intreadwrite.h"
+#include "libavutil/avassert.h"
+
+#include "defs.h"
+#include "mathops.h"
+#include "vlc.h"
+
+/*
+ * Safe bitstream reading:
+ * optionally, the get_bits API can check to ensure that we
+ * don't read past input buffer boundaries. This is protected
+ * with CONFIG_SAFE_BITSTREAM_READER at the global level, and
+ * then below that with UNCHECKED_BITSTREAM_READER at the per-
+ * decoder level. This means that decoders that check internally
+ * can "#define UNCHECKED_BITSTREAM_READER 1" to disable
+ * overread checks.
+ * Boundary checking causes a minor performance penalty so for
+ * applications that won't want/need this, it can be disabled
+ * globally using "#define CONFIG_SAFE_BITSTREAM_READER 0".
+ */
+#ifndef UNCHECKED_BITSTREAM_READER
+#define UNCHECKED_BITSTREAM_READER !CONFIG_SAFE_BITSTREAM_READER
+#endif
+
+#ifndef CACHED_BITSTREAM_READER
+#define CACHED_BITSTREAM_READER 0
+#endif
+
+#if CACHED_BITSTREAM_READER
+
+// we always want the LE implementation, to provide get_bits_le()
+#define BITSTREAM_LE
+
+#ifndef BITSTREAM_READER_LE
+# define BITSTREAM_BE
+# define BITSTREAM_DEFAULT_BE
+#endif
+
+#include "bitstream.h"
+
+#undef BITSTREAM_LE
+#undef BITSTREAM_BE
+#undef BITSTREAM_DEFAULT_BE
+
+typedef BitstreamContext GetBitContext;
+
+#define get_bits_count bits_tell
+#define get_bits_left bits_left
+#define skip_bits_long bits_skip
+#define skip_bits bits_skip
+#define get_bits bits_read_nz
+#define get_bitsz bits_read
+#define get_bits_long bits_read
+#define get_bits1 bits_read_bit
+#define get_bits64 bits_read_64
+#define get_xbits bits_read_xbits
+#define get_sbits bits_read_signed_nz
+#define get_sbits_long bits_read_signed
+#define show_bits bits_peek
+#define show_bits_long bits_peek
+#define init_get_bits bits_init
+#define init_get_bits8 bits_init8
+#define align_get_bits bits_align
+#define get_vlc2 bits_read_vlc
+
+#define init_get_bits8_le(s, buffer, byte_size) bits_init8_le((BitstreamContextLE*)s, buffer, byte_size)
+#define get_bits_le(s, n) bits_read_le((BitstreamContextLE*)s, n)
+
+#define show_bits1(s) bits_peek(s, 1)
+#define skip_bits1(s) bits_skip(s, 1)
+
+#define skip_1stop_8data_bits bits_skip_1stop_8data
+
+#else // CACHED_BITSTREAM_READER
+
+typedef struct GetBitContext {
+ const uint8_t *buffer, *buffer_end;
+ int index;
+ int size_in_bits;
+ int size_in_bits_plus8;
+} GetBitContext;
+
+static inline unsigned int get_bits(GetBitContext *s, int n);
+static inline void skip_bits(GetBitContext *s, int n);
+static inline unsigned int show_bits(GetBitContext *s, int n);
+
+/* Bitstream reader API docs:
+ * name
+ * arbitrary name which is used as prefix for the internal variables
+ *
+ * gb
+ * getbitcontext
+ *
+ * OPEN_READER(name, gb)
+ * load gb into local variables
+ *
+ * CLOSE_READER(name, gb)
+ * store local vars in gb
+ *
+ * UPDATE_CACHE(name, gb)
+ * Refill the internal cache from the bitstream.
+ * After this call at least MIN_CACHE_BITS will be available.
+ *
+ * GET_CACHE(name, gb)
+ * Will output the contents of the internal cache,
+ * next bit is MSB of 32 or 64 bits (FIXME 64 bits).
+ *
+ * SHOW_UBITS(name, gb, num)
+ * Will return the next num bits.
+ *
+ * SHOW_SBITS(name, gb, num)
+ * Will return the next num bits and do sign extension.
+ *
+ * SKIP_BITS(name, gb, num)
+ * Will skip over the next num bits.
+ * Note, this is equivalent to SKIP_CACHE; SKIP_COUNTER.
+ *
+ * SKIP_CACHE(name, gb, num)
+ * Will remove the next num bits from the cache (note SKIP_COUNTER
+ * MUST be called before UPDATE_CACHE / CLOSE_READER).
+ *
+ * SKIP_COUNTER(name, gb, num)
+ * Will increment the internal bit counter (see SKIP_CACHE & SKIP_BITS).
+ *
+ * LAST_SKIP_BITS(name, gb, num)
+ * Like SKIP_BITS, to be used if next call is UPDATE_CACHE or CLOSE_READER.
+ *
+ * BITS_LEFT(name, gb)
+ * Return the number of bits left
+ *
+ * For examples see get_bits, show_bits, skip_bits, get_vlc.
+ */
+
+#if defined LONG_BITSTREAM_READER
+# define MIN_CACHE_BITS 32
+#else
+# define MIN_CACHE_BITS 25
+#endif
+
+#define OPEN_READER_NOSIZE(name, gb) \
+ unsigned int name ## _index = (gb)->index; \
+ unsigned int av_unused name ## _cache
+
+#if UNCHECKED_BITSTREAM_READER
+#define OPEN_READER(name, gb) OPEN_READER_NOSIZE(name, gb)
+
+#define BITS_AVAILABLE(name, gb) 1
+#else
+#define OPEN_READER(name, gb) \
+ OPEN_READER_NOSIZE(name, gb); \
+ unsigned int name ## _size_plus8 = (gb)->size_in_bits_plus8
+
+#define BITS_AVAILABLE(name, gb) name ## _index < name ## _size_plus8
+#endif
+
+#define CLOSE_READER(name, gb) (gb)->index = name ## _index
+
+# ifdef LONG_BITSTREAM_READER
+
+# define UPDATE_CACHE_LE(name, gb) name ## _cache = \
+ AV_RL64((gb)->buffer + (name ## _index >> 3)) >> (name ## _index & 7)
+
+# define UPDATE_CACHE_BE(name, gb) name ## _cache = \
+ AV_RB64((gb)->buffer + (name ## _index >> 3)) >> (32 - (name ## _index & 7))
+
+#else
+
+# define UPDATE_CACHE_LE(name, gb) name ## _cache = \
+ AV_RL32((gb)->buffer + (name ## _index >> 3)) >> (name ## _index & 7)
+
+# define UPDATE_CACHE_BE(name, gb) name ## _cache = \
+ AV_RB32((gb)->buffer + (name ## _index >> 3)) << (name ## _index & 7)
+
+#endif
+
+
+#ifdef BITSTREAM_READER_LE
+
+# define UPDATE_CACHE(name, gb) UPDATE_CACHE_LE(name, gb)
+
+# define SKIP_CACHE(name, gb, num) name ## _cache >>= (num)
+
+#else
+
+# define UPDATE_CACHE(name, gb) UPDATE_CACHE_BE(name, gb)
+
+# define SKIP_CACHE(name, gb, num) name ## _cache <<= (num)
+
+#endif
+
+#if UNCHECKED_BITSTREAM_READER
+# define SKIP_COUNTER(name, gb, num) name ## _index += (num)
+#else
+# define SKIP_COUNTER(name, gb, num) \
+ name ## _index = FFMIN(name ## _size_plus8, name ## _index + (num))
+#endif
+
+#define BITS_LEFT(name, gb) ((int)((gb)->size_in_bits - name ## _index))
+
+#define SKIP_BITS(name, gb, num) \
+ do { \
+ SKIP_CACHE(name, gb, num); \
+ SKIP_COUNTER(name, gb, num); \
+ } while (0)
+
+#define LAST_SKIP_BITS(name, gb, num) SKIP_COUNTER(name, gb, num)
+
+#define SHOW_UBITS_LE(name, gb, num) zero_extend(name ## _cache, num)
+#define SHOW_SBITS_LE(name, gb, num) sign_extend(name ## _cache, num)
+
+#define SHOW_UBITS_BE(name, gb, num) NEG_USR32(name ## _cache, num)
+#define SHOW_SBITS_BE(name, gb, num) NEG_SSR32(name ## _cache, num)
+
+#ifdef BITSTREAM_READER_LE
+# define SHOW_UBITS(name, gb, num) SHOW_UBITS_LE(name, gb, num)
+# define SHOW_SBITS(name, gb, num) SHOW_SBITS_LE(name, gb, num)
+#else
+# define SHOW_UBITS(name, gb, num) SHOW_UBITS_BE(name, gb, num)
+# define SHOW_SBITS(name, gb, num) SHOW_SBITS_BE(name, gb, num)
+#endif
+
+#define GET_CACHE(name, gb) ((uint32_t) name ## _cache)
+
+
+static inline int get_bits_count(const GetBitContext *s)
+{
+ return s->index;
+}
+
+/**
+ * Skips the specified number of bits.
+ * @param n the number of bits to skip,
+ * For the UNCHECKED_BITSTREAM_READER this must not cause the distance
+ * from the start to overflow int32_t. Staying within the bitstream + padding
+ * is sufficient, too.
+ */
+static inline void skip_bits_long(GetBitContext *s, int n)
+{
+#if UNCHECKED_BITSTREAM_READER
+ s->index += n;
+#else
+ s->index += av_clip(n, -s->index, s->size_in_bits_plus8 - s->index);
+#endif
+}
+
+/**
+ * Read MPEG-1 dc-style VLC (sign bit + mantissa with no MSB).
+ * if MSB not set it is negative
+ * @param n length in bits
+ */
+static inline int get_xbits(GetBitContext *s, int n)
+{
+ register int sign;
+ register int32_t cache;
+ OPEN_READER(re, s);
+ av_assert2(n>0 && n<=25);
+ UPDATE_CACHE(re, s);
+ cache = GET_CACHE(re, s);
+ sign = ~cache >> 31;
+ LAST_SKIP_BITS(re, s, n);
+ CLOSE_READER(re, s);
+ return (NEG_USR32(sign ^ cache, n) ^ sign) - sign;
+}
+
+static inline int get_xbits_le(GetBitContext *s, int n)
+{
+ register int sign;
+ register int32_t cache;
+ OPEN_READER(re, s);
+ av_assert2(n>0 && n<=25);
+ UPDATE_CACHE_LE(re, s);
+ cache = GET_CACHE(re, s);
+ sign = sign_extend(~cache, n) >> 31;
+ LAST_SKIP_BITS(re, s, n);
+ CLOSE_READER(re, s);
+ return (zero_extend(sign ^ cache, n) ^ sign) - sign;
+}
+
+static inline int get_sbits(GetBitContext *s, int n)
+{
+ register int tmp;
+ OPEN_READER(re, s);
+ av_assert2(n>0 && n<=25);
+ UPDATE_CACHE(re, s);
+ tmp = SHOW_SBITS(re, s, n);
+ LAST_SKIP_BITS(re, s, n);
+ CLOSE_READER(re, s);
+ return tmp;
+}
+
+/**
+ * Read 1-25 bits.
+ */
+static inline unsigned int get_bits(GetBitContext *s, int n)
+{
+ register unsigned int tmp;
+ OPEN_READER(re, s);
+ av_assert2(n>0 && n<=25);
+ UPDATE_CACHE(re, s);
+ tmp = SHOW_UBITS(re, s, n);
+ LAST_SKIP_BITS(re, s, n);
+ CLOSE_READER(re, s);
+ av_assert2(tmp < UINT64_C(1) << n);
+ return tmp;
+}
+
+/**
+ * Read 0-25 bits.
+ */
+static av_always_inline int get_bitsz(GetBitContext *s, int n)
+{
+ return n ? get_bits(s, n) : 0;
+}
+
+static inline unsigned int get_bits_le(GetBitContext *s, int n)
+{
+ register int tmp;
+ OPEN_READER(re, s);
+ av_assert2(n>0 && n<=25);
+ UPDATE_CACHE_LE(re, s);
+ tmp = SHOW_UBITS_LE(re, s, n);
+ LAST_SKIP_BITS(re, s, n);
+ CLOSE_READER(re, s);
+ return tmp;
+}
+
+/**
+ * Show 1-25 bits.
+ */
+static inline unsigned int show_bits(GetBitContext *s, int n)
+{
+ register unsigned int tmp;
+ OPEN_READER_NOSIZE(re, s);
+ av_assert2(n>0 && n<=25);
+ UPDATE_CACHE(re, s);
+ tmp = SHOW_UBITS(re, s, n);
+ return tmp;
+}
+
+static inline void skip_bits(GetBitContext *s, int n)
+{
+ OPEN_READER(re, s);
+ LAST_SKIP_BITS(re, s, n);
+ CLOSE_READER(re, s);
+}
+
+static inline unsigned int get_bits1(GetBitContext *s)
+{
+ unsigned int index = s->index;
+ uint8_t result = s->buffer[index >> 3];
+#ifdef BITSTREAM_READER_LE
+ result >>= index & 7;
+ result &= 1;
+#else
+ result <<= index & 7;
+ result >>= 8 - 1;
+#endif
+#if !UNCHECKED_BITSTREAM_READER
+ if (s->index < s->size_in_bits_plus8)
+#endif
+ index++;
+ s->index = index;
+
+ return result;
+}
+
+static inline unsigned int show_bits1(GetBitContext *s)
+{
+ return show_bits(s, 1);
+}
+
+static inline void skip_bits1(GetBitContext *s)
+{
+ skip_bits(s, 1);
+}
+
+/**
+ * Read 0-32 bits.
+ */
+static inline unsigned int get_bits_long(GetBitContext *s, int n)
+{
+ av_assert2(n>=0 && n<=32);
+ if (!n) {
+ return 0;
+ } else if (n <= MIN_CACHE_BITS) {
+ return get_bits(s, n);
+ } else {
+#ifdef BITSTREAM_READER_LE
+ unsigned ret = get_bits(s, 16);
+ return ret | (get_bits(s, n - 16) << 16);
+#else
+ unsigned ret = get_bits(s, 16) << (n - 16);
+ return ret | get_bits(s, n - 16);
+#endif
+ }
+}
+
+/**
+ * Read 0-64 bits.
+ */
+static inline uint64_t get_bits64(GetBitContext *s, int n)
+{
+ if (n <= 32) {
+ return get_bits_long(s, n);
+ } else {
+#ifdef BITSTREAM_READER_LE
+ uint64_t ret = get_bits_long(s, 32);
+ return ret | (uint64_t) get_bits_long(s, n - 32) << 32;
+#else
+ uint64_t ret = (uint64_t) get_bits_long(s, n - 32) << 32;
+ return ret | get_bits_long(s, 32);
+#endif
+ }
+}
+
+/**
+ * Read 0-32 bits as a signed integer.
+ */
+static inline int get_sbits_long(GetBitContext *s, int n)
+{
+ // sign_extend(x, 0) is undefined
+ if (!n)
+ return 0;
+
+ return sign_extend(get_bits_long(s, n), n);
+}
+
+/**
+ * Read 0-64 bits as a signed integer.
+ */
+static inline int64_t get_sbits64(GetBitContext *s, int n)
+{
+ // sign_extend(x, 0) is undefined
+ if (!n)
+ return 0;
+
+ return sign_extend64(get_bits64(s, n), n);
+}
+
+/**
+ * Show 0-32 bits.
+ */
+static inline unsigned int show_bits_long(GetBitContext *s, int n)
+{
+ if (n <= MIN_CACHE_BITS) {
+ return show_bits(s, n);
+ } else {
+ GetBitContext gb = *s;
+ return get_bits_long(&gb, n);
+ }
+}
+
+
+/**
+ * Initialize GetBitContext.
+ * @param buffer bitstream buffer, must be AV_INPUT_BUFFER_PADDING_SIZE bytes
+ * larger than the actual read bits because some optimized bitstream
+ * readers read 32 or 64 bit at once and could read over the end
+ * @param bit_size the size of the buffer in bits
+ * @return 0 on success, AVERROR_INVALIDDATA if the buffer_size would overflow.
+ */
+static inline int init_get_bits(GetBitContext *s, const uint8_t *buffer,
+ int bit_size)
+{
+ int buffer_size;
+ int ret = 0;
+
+ if (bit_size >= INT_MAX - FFMAX(7, AV_INPUT_BUFFER_PADDING_SIZE*8) || bit_size < 0 || !buffer) {
+ bit_size = 0;
+ buffer = NULL;
+ ret = AVERROR_INVALIDDATA;
+ }
+
+ buffer_size = (bit_size + 7) >> 3;
+
+ s->buffer = buffer;
+ s->size_in_bits = bit_size;
+ s->size_in_bits_plus8 = bit_size + 8;
+ s->buffer_end = buffer + buffer_size;
+ s->index = 0;
+
+ return ret;
+}
+
+/**
+ * Initialize GetBitContext.
+ * @param buffer bitstream buffer, must be AV_INPUT_BUFFER_PADDING_SIZE bytes
+ * larger than the actual read bits because some optimized bitstream
+ * readers read 32 or 64 bit at once and could read over the end
+ * @param byte_size the size of the buffer in bytes
+ * @return 0 on success, AVERROR_INVALIDDATA if the buffer_size would overflow.
+ */
+static inline int init_get_bits8(GetBitContext *s, const uint8_t *buffer,
+ int byte_size)
+{
+ if (byte_size > INT_MAX / 8 || byte_size < 0)
+ byte_size = -1;
+ return init_get_bits(s, buffer, byte_size * 8);
+}
+
+static inline int init_get_bits8_le(GetBitContext *s, const uint8_t *buffer,
+ int byte_size)
+{
+ if (byte_size > INT_MAX / 8 || byte_size < 0)
+ byte_size = -1;
+ return init_get_bits(s, buffer, byte_size * 8);
+}
+
+static inline const uint8_t *align_get_bits(GetBitContext *s)
+{
+ int n = -get_bits_count(s) & 7;
+ if (n)
+ skip_bits(s, n);
+ return s->buffer + (s->index >> 3);
+}
+
+/**
+ * If the vlc code is invalid and max_depth=1, then no bits will be removed.
+ * If the vlc code is invalid and max_depth>1, then the number of bits removed
+ * is undefined.
+ */
+#define GET_VLC(code, name, gb, table, bits, max_depth) \
+ do { \
+ int n, nb_bits; \
+ unsigned int index; \
+ \
+ index = SHOW_UBITS(name, gb, bits); \
+ code = table[index].sym; \
+ n = table[index].len; \
+ \
+ if (max_depth > 1 && n < 0) { \
+ LAST_SKIP_BITS(name, gb, bits); \
+ UPDATE_CACHE(name, gb); \
+ \
+ nb_bits = -n; \
+ \
+ index = SHOW_UBITS(name, gb, nb_bits) + code; \
+ code = table[index].sym; \
+ n = table[index].len; \
+ if (max_depth > 2 && n < 0) { \
+ LAST_SKIP_BITS(name, gb, nb_bits); \
+ UPDATE_CACHE(name, gb); \
+ \
+ nb_bits = -n; \
+ \
+ index = SHOW_UBITS(name, gb, nb_bits) + code; \
+ code = table[index].sym; \
+ n = table[index].len; \
+ } \
+ } \
+ SKIP_BITS(name, gb, n); \
+ } while (0)
+
+#define GET_RL_VLC(level, run, name, gb, table, bits, \
+ max_depth, need_update) \
+ do { \
+ int n, nb_bits; \
+ unsigned int index; \
+ \
+ index = SHOW_UBITS(name, gb, bits); \
+ level = table[index].level; \
+ n = table[index].len; \
+ \
+ if (max_depth > 1 && n < 0) { \
+ SKIP_BITS(name, gb, bits); \
+ if (need_update) { \
+ UPDATE_CACHE(name, gb); \
+ } \
+ \
+ nb_bits = -n; \
+ \
+ index = SHOW_UBITS(name, gb, nb_bits) + level; \
+ level = table[index].level; \
+ n = table[index].len; \
+ if (max_depth > 2 && n < 0) { \
+ LAST_SKIP_BITS(name, gb, nb_bits); \
+ if (need_update) { \
+ UPDATE_CACHE(name, gb); \
+ } \
+ nb_bits = -n; \
+ \
+ index = SHOW_UBITS(name, gb, nb_bits) + level; \
+ level = table[index].level; \
+ n = table[index].len; \
+ } \
+ } \
+ run = table[index].run; \
+ SKIP_BITS(name, gb, n); \
+ } while (0)
+
+/**
+ * Parse a vlc code.
+ * @param bits is the number of bits which will be read at once, must be
+ * identical to nb_bits in init_vlc()
+ * @param max_depth is the number of times bits bits must be read to completely
+ * read the longest vlc code
+ * = (max_vlc_length + bits - 1) / bits
+ * @returns the code parsed or -1 if no vlc matches
+ */
+static av_always_inline int get_vlc2(GetBitContext *s, const VLCElem *table,
+ int bits, int max_depth)
+{
+ int code;
+
+ OPEN_READER(re, s);
+ UPDATE_CACHE(re, s);
+
+ GET_VLC(code, re, s, table, bits, max_depth);
+
+ CLOSE_READER(re, s);
+
+ return code;
+}
+
+static inline int decode012(GetBitContext *gb)
+{
+ int n;
+ n = get_bits1(gb);
+ if (n == 0)
+ return 0;
+ else
+ return get_bits1(gb) + 1;
+}
+
+static inline int decode210(GetBitContext *gb)
+{
+ if (get_bits1(gb))
+ return 0;
+ else
+ return 2 - get_bits1(gb);
+}
+
+static inline int get_bits_left(GetBitContext *gb)
+{
+ return gb->size_in_bits - get_bits_count(gb);
+}
+
+static inline int skip_1stop_8data_bits(GetBitContext *gb)
+{
+ if (get_bits_left(gb) <= 0)
+ return AVERROR_INVALIDDATA;
+
+ while (get_bits1(gb)) {
+ skip_bits(gb, 8);
+ if (get_bits_left(gb) <= 0)
+ return AVERROR_INVALIDDATA;
+ }
+
+ return 0;
+}
+
+#endif // CACHED_BITSTREAM_READER
+
+#endif /* AVCODEC_GET_BITS_H */
generated by cgit v1.2.3 (git 2.39.1) at 2024-10-30 17:16:28 +0000