diff --git a/SOURCES/rhbz1881156.patch b/SOURCES/rhbz1881156.patch
new file mode 100644
index 0000000..faf58f4
--- /dev/null
+++ b/SOURCES/rhbz1881156.patch
@@ -0,0 +1,2152 @@
+From ce3b0936620b9abb2d6d21d3e608f37f3c7302d9 Mon Sep 17 00:00:00 2001
+From: rpm-build <rpm-build>
+Date: Thu, 1 Oct 2020 10:34:27 +0200
+Subject: [PATCH] rhbz1881156.patch
+
+---
+ c/common/constants.c | 15 +
+ c/common/constants.h | 136 ++++++++
+ c/common/platform.h | 8 +-
+ c/dec/bit_reader.c | 28 ++
+ c/dec/bit_reader.h | 74 +++-
+ c/dec/decode.c | 695 ++++++++++++++++++++++----------------
+ c/dec/huffman.h | 71 +++-
+ c/dec/prefix.h | 18 -
+ c/dec/state.c | 23 +-
+ c/dec/state.h | 181 ++++++++--
+ c/enc/brotli_bit_stream.c | 21 +-
+ research/brotli_decoder.c | 1 +
+ scripts/sources.lst | 1 +
+ setup.py | 1 +
+ 14 files changed, 865 insertions(+), 408 deletions(-)
+ create mode 100644 c/common/constants.c
+
+diff --git a/c/common/constants.c b/c/common/constants.c
+new file mode 100644
+index 0000000..6bad9f6
+--- /dev/null
++++ b/c/common/constants.c
+@@ -0,0 +1,15 @@
++/* Copyright 2013 Google Inc. All Rights Reserved.
++
++ Distributed under MIT license.
++ See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
++*/
++
++#include "./constants.h"
++
++const BrotliPrefixCodeRange
++ _kBrotliPrefixCodeRanges[BROTLI_NUM_BLOCK_LEN_SYMBOLS] = {
++ {1, 2}, {5, 2}, {9, 2}, {13, 2}, {17, 3}, {25, 3},
++ {33, 3}, {41, 3}, {49, 4}, {65, 4}, {81, 4}, {97, 4},
++ {113, 5}, {145, 5}, {177, 5}, {209, 5}, {241, 6}, {305, 6},
++ {369, 7}, {497, 8}, {753, 9}, {1265, 10}, {2289, 11}, {4337, 12},
++ {8433, 13}, {16625, 24}};
+diff --git a/c/common/constants.h b/c/common/constants.h
+index d1b88d1..e848195 100644
+--- a/c/common/constants.h
++++ b/c/common/constants.h
+@@ -4,9 +4,18 @@
+ See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+ */
+
++/**
++ * @file
++ * Common constants used in decoder and encoder API.
++ */
++
+ #ifndef BROTLI_COMMON_CONSTANTS_H_
+ #define BROTLI_COMMON_CONSTANTS_H_
+
++#include "./platform.h"
++#include <brotli/port.h>
++#include <brotli/types.h>
++
+ /* Specification: 7.3. Encoding of the context map */
+ #define BROTLI_CONTEXT_MAP_MAX_RLE 16
+
+@@ -29,12 +38,31 @@
+ #define BROTLI_INITIAL_REPEATED_CODE_LENGTH 8
+
+ /* "Large Window Brotli" */
++
++/**
++ * The theoretical maximum number of distance bits specified for large window
++ * brotli, for 64-bit encoders and decoders. Even when in practice 32-bit
++ * encoders and decoders only support up to 30 max distance bits, the value is
++ * set to 62 because it affects the large window brotli file format.
++ * Specifically, it affects the encoding of simple huffman tree for distances,
++ * see Specification RFC 7932 chapter 3.4.
++ */
+ #define BROTLI_LARGE_MAX_DISTANCE_BITS 62U
+ #define BROTLI_LARGE_MIN_WBITS 10
++/**
++ * The maximum supported large brotli window bits by the encoder and decoder.
++ * Large window brotli allows up to 62 bits, however the current encoder and
++ * decoder, designed for 32-bit integers, only support up to 30 bits maximum.
++ */
+ #define BROTLI_LARGE_MAX_WBITS 30
+
+ /* Specification: 4. Encoding of distances */
+ #define BROTLI_NUM_DISTANCE_SHORT_CODES 16
++/**
++ * Maximal number of "postfix" bits.
++ *
++ * Number of "postfix" bits is stored as 2 bits in meta-block header.
++ */
+ #define BROTLI_MAX_NPOSTFIX 3
+ #define BROTLI_MAX_NDIRECT 120
+ #define BROTLI_MAX_DISTANCE_BITS 24U
+@@ -45,9 +73,22 @@
+ #define BROTLI_NUM_DISTANCE_SYMBOLS \
+ BROTLI_DISTANCE_ALPHABET_SIZE( \
+ BROTLI_MAX_NDIRECT, BROTLI_MAX_NPOSTFIX, BROTLI_LARGE_MAX_DISTANCE_BITS)
++
++/* ((1 << 26) - 4) is the maximal distance that can be expressed in RFC 7932
++ brotli stream using NPOSTFIX = 0 and NDIRECT = 0. With other NPOSTFIX and
++ NDIRECT values distances up to ((1 << 29) + 88) could be expressed. */
+ #define BROTLI_MAX_DISTANCE 0x3FFFFFC
++
++/* ((1 << 31) - 4) is the safe distance limit. Using this number as a limit
++ allows safe distance calculation without overflows, given the distance
++ alphabet size is limited to corresponding size
++ (see kLargeWindowDistanceCodeLimits). */
+ #define BROTLI_MAX_ALLOWED_DISTANCE 0x7FFFFFFC
+
++
++/* Specification: 4. Encoding of Literal Insertion Lengths and Copy Lengths */
++#define BROTLI_NUM_INS_COPY_CODES 24
++
+ /* 7.1. Context modes and context ID lookup for literals */
+ /* "context IDs for literals are in the range of 0..63" */
+ #define BROTLI_LITERAL_CONTEXT_BITS 6
+@@ -61,4 +102,99 @@
+ #define BROTLI_WINDOW_GAP 16
+ #define BROTLI_MAX_BACKWARD_LIMIT(W) (((size_t)1 << (W)) - BROTLI_WINDOW_GAP)
+
++typedef struct BrotliDistanceCodeLimit {
++ uint32_t max_alphabet_size;
++ uint32_t max_distance;
++} BrotliDistanceCodeLimit;
++
++/* This function calculates maximal size of distance alphabet, such that the
++ distances greater than the given values can not be represented.
++
++ This limits are designed to support fast and safe 32-bit decoders.
++ "32-bit" means that signed integer values up to ((1 << 31) - 1) could be
++ safely expressed.
++
++ Brotli distance alphabet symbols do not represent consecutive distance
++ ranges. Each distance alphabet symbol (excluding direct distances and short
++ codes), represent interleaved (for NPOSTFIX > 0) range of distances.
++ A "group" of consecutive (1 << NPOSTFIX) symbols represent non-interleaved
++ range. Two consecutive groups require the same amount of "extra bits".
++
++ It is important that distance alphabet represents complete "groups".
++ To avoid complex logic on encoder side about interleaved ranges
++ it was decided to restrict both sides to complete distance code "groups".
++ */
++BROTLI_UNUSED_FUNCTION BrotliDistanceCodeLimit BrotliCalculateDistanceCodeLimit(
++ uint32_t max_distance, uint32_t npostfix, uint32_t ndirect) {
++ BrotliDistanceCodeLimit result;
++ /* Marking this function as unused, because not all files
++ including "constants.h" use it -> compiler warns about that. */
++ BROTLI_UNUSED(&BrotliCalculateDistanceCodeLimit);
++ if (max_distance <= ndirect) {
++ /* This case never happens / exists only for the sake of completeness. */
++ result.max_alphabet_size = max_distance + BROTLI_NUM_DISTANCE_SHORT_CODES;
++ result.max_distance = max_distance;
++ return result;
++ } else {
++ /* The first prohibited value. */
++ uint32_t forbidden_distance = max_distance + 1;
++ /* Subtract "directly" encoded region. */
++ uint32_t offset = forbidden_distance - ndirect - 1;
++ uint32_t ndistbits = 0;
++ uint32_t tmp;
++ uint32_t half;
++ uint32_t group;
++ /* Postfix for the last dcode in the group. */
++ uint32_t postfix = (1u << npostfix) - 1;
++ uint32_t extra;
++ uint32_t start;
++ /* Remove postfix and "head-start". */
++ offset = (offset >> npostfix) + 4;
++ /* Calculate the number of distance bits. */
++ tmp = offset / 2;
++ /* Poor-man's log2floor, to avoid extra dependencies. */
++ while (tmp != 0) {ndistbits++; tmp = tmp >> 1;}
++ /* One bit is covered with subrange addressing ("half"). */
++ ndistbits--;
++ /* Find subrange. */
++ half = (offset >> ndistbits) & 1;
++ /* Calculate the "group" part of dcode. */
++ group = ((ndistbits - 1) << 1) | half;
++ /* Calculated "group" covers the prohibited distance value. */
++ if (group == 0) {
++ /* This case is added for correctness; does not occur for limit > 128. */
++ result.max_alphabet_size = ndirect + BROTLI_NUM_DISTANCE_SHORT_CODES;
++ result.max_distance = ndirect;
++ return result;
++ }
++ /* Decrement "group", so it is the last permitted "group". */
++ group--;
++ /* After group was decremented, ndistbits and half must be recalculated. */
++ ndistbits = (group >> 1) + 1;
++ /* The last available distance in the subrange has all extra bits set. */
++ extra = (1u << ndistbits) - 1;
++ /* Calculate region start. NB: ndistbits >= 1. */
++ start = (1u << (ndistbits + 1)) - 4;
++ /* Move to subregion. */
++ start += (group & 1) << ndistbits;
++ /* Calculate the alphabet size. */
++ result.max_alphabet_size = ((group << npostfix) | postfix) + ndirect +
++ BROTLI_NUM_DISTANCE_SHORT_CODES + 1;
++ /* Calculate the maximal distance representable by alphabet. */
++ result.max_distance = ((start + extra) << npostfix) + postfix + ndirect + 1;
++ return result;
++ }
++}
++
++/* Represents the range of values belonging to a prefix code:
++ [offset, offset + 2^nbits) */
++typedef struct {
++ uint16_t offset;
++ uint8_t nbits;
++} BrotliPrefixCodeRange;
++
++/* "Soft-private", it is exported, but not "advertised" as API. */
++BROTLI_COMMON_API extern const BrotliPrefixCodeRange
++ _kBrotliPrefixCodeRanges[BROTLI_NUM_BLOCK_LEN_SYMBOLS];
++
+ #endif /* BROTLI_COMMON_CONSTANTS_H_ */
+diff --git a/c/common/platform.h b/c/common/platform.h
+index 0d84b19..94bf773 100755
+--- a/c/common/platform.h
++++ b/c/common/platform.h
+@@ -197,6 +197,10 @@ OR:
+
+ #endif /* ARMv8 */
+
++#if defined(__ARM_NEON__) || defined(__ARM_NEON)
++#define BROTLI_TARGET_NEON
++#endif
++
+ #if defined(__i386) || defined(_M_IX86)
+ #define BROTLI_TARGET_X86
+ #endif
+@@ -456,20 +460,20 @@ static BROTLI_INLINE void BROTLI_UNALIGNED_STORE64LE(void* p, uint64_t v) {
+ #endif
+
+ #if defined(BROTLI_ENABLE_LOG)
+-#define BROTLI_DCHECK(x) assert(x)
+ #define BROTLI_LOG(x) printf x
+ #else
+-#define BROTLI_DCHECK(x)
+ #define BROTLI_LOG(x)
+ #endif
+
+ #if defined(BROTLI_DEBUG) || defined(BROTLI_ENABLE_LOG)
++#define BROTLI_DCHECK(x) assert(x)
+ static BROTLI_INLINE void BrotliDump(const char* f, int l, const char* fn) {
+ fprintf(stderr, "%s:%d (%s)\n", f, l, fn);
+ fflush(stderr);
+ }
+ #define BROTLI_DUMP() BrotliDump(__FILE__, __LINE__, __FUNCTION__)
+ #else
++#define BROTLI_DCHECK(x)
+ #define BROTLI_DUMP() (void)(0)
+ #endif
+
+diff --git a/c/dec/bit_reader.c b/c/dec/bit_reader.c
+index 722fd90..7f7b256 100644
+--- a/c/dec/bit_reader.c
++++ b/c/dec/bit_reader.c
+@@ -15,6 +15,17 @@
+ extern "C" {
+ #endif
+
++const uint32_t kBrotliBitMask[33] = { 0x00000000,
++ 0x00000001, 0x00000003, 0x00000007, 0x0000000F,
++ 0x0000001F, 0x0000003F, 0x0000007F, 0x000000FF,
++ 0x000001FF, 0x000003FF, 0x000007FF, 0x00000FFF,
++ 0x00001FFF, 0x00003FFF, 0x00007FFF, 0x0000FFFF,
++ 0x0001FFFF, 0x0003FFFF, 0x0007FFFF, 0x000FFFFF,
++ 0x001FFFFF, 0x003FFFFF, 0x007FFFFF, 0x00FFFFFF,
++ 0x01FFFFFF, 0x03FFFFFF, 0x07FFFFFF, 0x0FFFFFFF,
++ 0x1FFFFFFF, 0x3FFFFFFF, 0x7FFFFFFF, 0xFFFFFFFF
++};
++
+ void BrotliInitBitReader(BrotliBitReader* const br) {
+ br->val_ = 0;
+ br->bit_pos_ = sizeof(br->val_) << 3;
+@@ -43,6 +54,23 @@ BROTLI_BOOL BrotliWarmupBitReader(BrotliBitReader* const br) {
+ return BROTLI_TRUE;
+ }
+
++BROTLI_BOOL BrotliSafeReadBits32Slow(BrotliBitReader* const br,
++ uint32_t n_bits, uint32_t* val) {
++ uint32_t low_val;
++ uint32_t high_val;
++ BrotliBitReaderState memento;
++ BROTLI_DCHECK(n_bits <= 32);
++ BROTLI_DCHECK(n_bits > 24);
++ BrotliBitReaderSaveState(br, &memento);
++ if (!BrotliSafeReadBits(br, 16, &low_val) ||
++ !BrotliSafeReadBits(br, n_bits - 16, &high_val)) {
++ BrotliBitReaderRestoreState(br, &memento);
++ return BROTLI_FALSE;
++ }
++ *val = low_val | (high_val << 16);
++ return BROTLI_TRUE;
++}
++
+ #if defined(__cplusplus) || defined(c_plusplus)
+ } /* extern "C" */
+ #endif
+diff --git a/c/dec/bit_reader.h b/c/dec/bit_reader.h
+index c06e914..22bc060 100644
+--- a/c/dec/bit_reader.h
++++ b/c/dec/bit_reader.h
+@@ -11,6 +11,7 @@
+
+ #include <string.h> /* memcpy */
+
++#include "../common/constants.h"
+ #include "../common/platform.h"
+ #include <brotli/types.h>
+
+@@ -20,16 +21,7 @@ extern "C" {
+
+ #define BROTLI_SHORT_FILL_BIT_WINDOW_READ (sizeof(brotli_reg_t) >> 1)
+
+-static const uint32_t kBitMask[33] = { 0x00000000,
+- 0x00000001, 0x00000003, 0x00000007, 0x0000000F,
+- 0x0000001F, 0x0000003F, 0x0000007F, 0x000000FF,
+- 0x000001FF, 0x000003FF, 0x000007FF, 0x00000FFF,
+- 0x00001FFF, 0x00003FFF, 0x00007FFF, 0x0000FFFF,
+- 0x0001FFFF, 0x0003FFFF, 0x0007FFFF, 0x000FFFFF,
+- 0x001FFFFF, 0x003FFFFF, 0x007FFFFF, 0x00FFFFFF,
+- 0x01FFFFFF, 0x03FFFFFF, 0x07FFFFFF, 0x0FFFFFFF,
+- 0x1FFFFFFF, 0x3FFFFFFF, 0x7FFFFFFF, 0xFFFFFFFF
+-};
++BROTLI_INTERNAL extern const uint32_t kBrotliBitMask[33];
+
+ static BROTLI_INLINE uint32_t BitMask(uint32_t n) {
+ if (BROTLI_IS_CONSTANT(n) || BROTLI_HAS_UBFX) {
+@@ -37,7 +29,7 @@ static BROTLI_INLINE uint32_t BitMask(uint32_t n) {
+ "Unsigned Bit Field Extract" UBFX instruction on ARM. */
+ return ~((0xFFFFFFFFu) << n);
+ } else {
+- return kBitMask[n];
++ return kBrotliBitMask[n];
+ }
+ }
+
+@@ -65,6 +57,12 @@ BROTLI_INTERNAL void BrotliInitBitReader(BrotliBitReader* const br);
+ reading. */
+ BROTLI_INTERNAL BROTLI_BOOL BrotliWarmupBitReader(BrotliBitReader* const br);
+
++/* Fallback for BrotliSafeReadBits32. Extracted as noninlined method to unburden
++ the main code-path. Never called for RFC brotli streams, required only for
++ "large-window" mode and other extensions. */
++BROTLI_INTERNAL BROTLI_NOINLINE BROTLI_BOOL BrotliSafeReadBits32Slow(
++ BrotliBitReader* const br, uint32_t n_bits, uint32_t* val);
++
+ static BROTLI_INLINE void BrotliBitReaderSaveState(
+ BrotliBitReader* const from, BrotliBitReaderState* to) {
+ to->val_ = from->val_;
+@@ -87,8 +85,11 @@ static BROTLI_INLINE uint32_t BrotliGetAvailableBits(
+ }
+
+ /* Returns amount of unread bytes the bit reader still has buffered from the
+- BrotliInput, including whole bytes in br->val_. */
++ BrotliInput, including whole bytes in br->val_. Result is capped with
++ maximal ring-buffer size (larger number won't be utilized anyway). */
+ static BROTLI_INLINE size_t BrotliGetRemainingBytes(BrotliBitReader* br) {
++ static const size_t kCap = (size_t)1 << BROTLI_LARGE_MAX_WBITS;
++ if (br->avail_in > kCap) return kCap;
+ return br->avail_in + (BrotliGetAvailableBits(br) >> 3);
+ }
+
+@@ -237,15 +238,17 @@ static BROTLI_INLINE void BrotliBitReaderUnload(BrotliBitReader* br) {
+ static BROTLI_INLINE void BrotliTakeBits(
+ BrotliBitReader* const br, uint32_t n_bits, uint32_t* val) {
+ *val = (uint32_t)BrotliGetBitsUnmasked(br) & BitMask(n_bits);
+- BROTLI_LOG(("[BrotliReadBits] %d %d %d val: %6x\n",
++ BROTLI_LOG(("[BrotliTakeBits] %d %d %d val: %6x\n",
+ (int)br->avail_in, (int)br->bit_pos_, (int)n_bits, (int)*val));
+ BrotliDropBits(br, n_bits);
+ }
+
+ /* Reads the specified number of bits from |br| and advances the bit pos.
+- Assumes that there is enough input to perform BrotliFillBitWindow. */
+-static BROTLI_INLINE uint32_t BrotliReadBits(
++ Assumes that there is enough input to perform BrotliFillBitWindow.
++ Up to 24 bits are allowed to be requested from this method. */
++static BROTLI_INLINE uint32_t BrotliReadBits24(
+ BrotliBitReader* const br, uint32_t n_bits) {
++ BROTLI_DCHECK(n_bits <= 24);
+ if (BROTLI_64_BITS || (n_bits <= 16)) {
+ uint32_t val;
+ BrotliFillBitWindow(br, n_bits);
+@@ -262,10 +265,32 @@ static BROTLI_INLINE uint32_t BrotliReadBits(
+ }
+ }
+
++/* Same as BrotliReadBits24, but allows reading up to 32 bits. */
++static BROTLI_INLINE uint32_t BrotliReadBits32(
++ BrotliBitReader* const br, uint32_t n_bits) {
++ BROTLI_DCHECK(n_bits <= 32);
++ if (BROTLI_64_BITS || (n_bits <= 16)) {
++ uint32_t val;
++ BrotliFillBitWindow(br, n_bits);
++ BrotliTakeBits(br, n_bits, &val);
++ return val;
++ } else {
++ uint32_t low_val;
++ uint32_t high_val;
++ BrotliFillBitWindow(br, 16);
++ BrotliTakeBits(br, 16, &low_val);
++ BrotliFillBitWindow(br, 16);
++ BrotliTakeBits(br, n_bits - 16, &high_val);
++ return low_val | (high_val << 16);
++ }
++}
++
+ /* Tries to read the specified amount of bits. Returns BROTLI_FALSE, if there
+- is not enough input. |n_bits| MUST be positive. */
++ is not enough input. |n_bits| MUST be positive.
++ Up to 24 bits are allowed to be requested from this method. */
+ static BROTLI_INLINE BROTLI_BOOL BrotliSafeReadBits(
+ BrotliBitReader* const br, uint32_t n_bits, uint32_t* val) {
++ BROTLI_DCHECK(n_bits <= 24);
+ while (BrotliGetAvailableBits(br) < n_bits) {
+ if (!BrotliPullByte(br)) {
+ return BROTLI_FALSE;
+@@ -275,6 +300,23 @@ static BROTLI_INLINE BROTLI_BOOL BrotliSafeReadBits(
+ return BROTLI_TRUE;
+ }
+
++/* Same as BrotliSafeReadBits, but allows reading up to 32 bits. */
++static BROTLI_INLINE BROTLI_BOOL BrotliSafeReadBits32(
++ BrotliBitReader* const br, uint32_t n_bits, uint32_t* val) {
++ BROTLI_DCHECK(n_bits <= 32);
++ if (BROTLI_64_BITS || (n_bits <= 24)) {
++ while (BrotliGetAvailableBits(br) < n_bits) {
++ if (!BrotliPullByte(br)) {
++ return BROTLI_FALSE;
++ }
++ }
++ BrotliTakeBits(br, n_bits, val);
++ return BROTLI_TRUE;
++ } else {
++ return BrotliSafeReadBits32Slow(br, n_bits, val);
++ }
++}
++
+ /* Advances the bit reader position to the next byte boundary and verifies
+ that any skipped bits are set to zero. */
+ static BROTLI_INLINE BROTLI_BOOL BrotliJumpToByteBoundary(BrotliBitReader* br) {
+diff --git a/c/dec/decode.c b/c/dec/decode.c
+index 674b829..ae5a3d3 100644
+--- a/c/dec/decode.c
++++ b/c/dec/decode.c
+@@ -6,10 +6,6 @@
+
+ #include <brotli/decode.h>
+
+-#if defined(__ARM_NEON__)
+-#include <arm_neon.h>
+-#endif
+-
+ #include <stdlib.h> /* free, malloc */
+ #include <string.h> /* memcpy, memset */
+
+@@ -24,6 +20,10 @@
+ #include "./prefix.h"
+ #include "./state.h"
+
++#if defined(BROTLI_TARGET_NEON)
++#include <arm_neon.h>
++#endif
++
+ #if defined(__cplusplus) || defined(c_plusplus)
+ extern "C" {
+ #endif
+@@ -41,7 +41,8 @@ extern "C" {
+
+ /* We need the slack region for the following reasons:
+ - doing up to two 16-byte copies for fast backward copying
+- - inserting transformed dictionary word (5 prefix + 24 base + 8 suffix) */
++ - inserting transformed dictionary word:
++ 5 prefix + 24 base + 8 suffix */
+ static const uint32_t kRingBufferWriteAheadSlack = 42;
+
+ static const uint8_t kCodeLengthCodeOrder[BROTLI_CODE_LENGTH_CODES] = {
+@@ -167,7 +168,7 @@ static BrotliDecoderErrorCode DecodeWindowBits(BrotliDecoderState* s,
+ }
+
+ static BROTLI_INLINE void memmove16(uint8_t* dst, uint8_t* src) {
+-#if defined(__ARM_NEON__)
++#if defined(BROTLI_TARGET_NEON)
+ vst1q_u8(dst, vld1q_u8(src));
+ #else
+ uint32_t buffer[4];
+@@ -274,7 +275,8 @@ static BrotliDecoderErrorCode BROTLI_NOINLINE DecodeMetaBlockLength(
+ s->loop_counter = i;
+ return BROTLI_DECODER_NEEDS_MORE_INPUT;
+ }
+- if (i + 1 == s->size_nibbles && s->size_nibbles > 4 && bits == 0) {
++ if (i + 1 == (int)s->size_nibbles && s->size_nibbles > 4 &&
++ bits == 0) {
+ return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_EXUBERANT_NIBBLE);
+ }
+ s->meta_block_remaining_len |= (int)(bits << (i * 4));
+@@ -323,7 +325,8 @@ static BrotliDecoderErrorCode BROTLI_NOINLINE DecodeMetaBlockLength(
+ s->loop_counter = i;
+ return BROTLI_DECODER_NEEDS_MORE_INPUT;
+ }
+- if (i + 1 == s->size_nibbles && s->size_nibbles > 1 && bits == 0) {
++ if (i + 1 == (int)s->size_nibbles && s->size_nibbles > 1 &&
++ bits == 0) {
+ return BROTLI_FAILURE(
+ BROTLI_DECODER_ERROR_FORMAT_EXUBERANT_META_NIBBLE);
+ }
+@@ -347,15 +350,17 @@ static BrotliDecoderErrorCode BROTLI_NOINLINE DecodeMetaBlockLength(
+ static BROTLI_INLINE uint32_t DecodeSymbol(uint32_t bits,
+ const HuffmanCode* table,
+ BrotliBitReader* br) {
+- table += bits & HUFFMAN_TABLE_MASK;
+- if (table->bits > HUFFMAN_TABLE_BITS) {
+- uint32_t nbits = table->bits - HUFFMAN_TABLE_BITS;
++ BROTLI_HC_MARK_TABLE_FOR_FAST_LOAD(table);
++ BROTLI_HC_ADJUST_TABLE_INDEX(table, bits & HUFFMAN_TABLE_MASK);
++ if (BROTLI_HC_FAST_LOAD_BITS(table) > HUFFMAN_TABLE_BITS) {
++ uint32_t nbits = BROTLI_HC_FAST_LOAD_BITS(table) - HUFFMAN_TABLE_BITS;
+ BrotliDropBits(br, HUFFMAN_TABLE_BITS);
+- table += table->value;
+- table += (bits >> HUFFMAN_TABLE_BITS) & BitMask(nbits);
++ BROTLI_HC_ADJUST_TABLE_INDEX(table,
++ BROTLI_HC_FAST_LOAD_VALUE(table) +
++ ((bits >> HUFFMAN_TABLE_BITS) & BitMask(nbits)));
+ }
+- BrotliDropBits(br, table->bits);
+- return table->value;
++ BrotliDropBits(br, BROTLI_HC_FAST_LOAD_BITS(table));
++ return BROTLI_HC_FAST_LOAD_VALUE(table);
+ }
+
+ /* Reads and decodes the next Huffman code from bit-stream.
+@@ -371,19 +376,20 @@ static BROTLI_NOINLINE BROTLI_BOOL SafeDecodeSymbol(
+ const HuffmanCode* table, BrotliBitReader* br, uint32_t* result) {
+ uint32_t val;
+ uint32_t available_bits = BrotliGetAvailableBits(br);
++ BROTLI_HC_MARK_TABLE_FOR_FAST_LOAD(table);
+ if (available_bits == 0) {
+- if (table->bits == 0) {
+- *result = table->value;
++ if (BROTLI_HC_FAST_LOAD_BITS(table) == 0) {
++ *result = BROTLI_HC_FAST_LOAD_VALUE(table);
+ return BROTLI_TRUE;
+ }
+ return BROTLI_FALSE; /* No valid bits at all. */
+ }
+ val = (uint32_t)BrotliGetBitsUnmasked(br);
+- table += val & HUFFMAN_TABLE_MASK;
+- if (table->bits <= HUFFMAN_TABLE_BITS) {
+- if (table->bits <= available_bits) {
+- BrotliDropBits(br, table->bits);
+- *result = table->value;
++ BROTLI_HC_ADJUST_TABLE_INDEX(table, val & HUFFMAN_TABLE_MASK);
++ if (BROTLI_HC_FAST_LOAD_BITS(table) <= HUFFMAN_TABLE_BITS) {
++ if (BROTLI_HC_FAST_LOAD_BITS(table) <= available_bits) {
++ BrotliDropBits(br, BROTLI_HC_FAST_LOAD_BITS(table));
++ *result = BROTLI_HC_FAST_LOAD_VALUE(table);
+ return BROTLI_TRUE;
+ } else {
+ return BROTLI_FALSE; /* Not enough bits for the first level. */
+@@ -394,15 +400,15 @@ static BROTLI_NOINLINE BROTLI_BOOL SafeDecodeSymbol(
+ }
+
+ /* Speculatively drop HUFFMAN_TABLE_BITS. */
+- val = (val & BitMask(table->bits)) >> HUFFMAN_TABLE_BITS;
++ val = (val & BitMask(BROTLI_HC_FAST_LOAD_BITS(table))) >> HUFFMAN_TABLE_BITS;
+ available_bits -= HUFFMAN_TABLE_BITS;
+- table += table->value + val;
+- if (available_bits < table->bits) {
++ BROTLI_HC_ADJUST_TABLE_INDEX(table, BROTLI_HC_FAST_LOAD_VALUE(table) + val);
++ if (available_bits < BROTLI_HC_FAST_LOAD_BITS(table)) {
+ return BROTLI_FALSE; /* Not enough bits for the second level. */
+ }
+
+- BrotliDropBits(br, HUFFMAN_TABLE_BITS + table->bits);
+- *result = table->value;
++ BrotliDropBits(br, HUFFMAN_TABLE_BITS + BROTLI_HC_FAST_LOAD_BITS(table));
++ *result = BROTLI_HC_FAST_LOAD_VALUE(table);
+ return BROTLI_TRUE;
+ }
+
+@@ -425,9 +431,10 @@ static BROTLI_INLINE void PreloadSymbol(int safe,
+ if (safe) {
+ return;
+ }
+- table += BrotliGetBits(br, HUFFMAN_TABLE_BITS);
+- *bits = table->bits;
+- *value = table->value;
++ BROTLI_HC_MARK_TABLE_FOR_FAST_LOAD(table);
++ BROTLI_HC_ADJUST_TABLE_INDEX(table, BrotliGetBits(br, HUFFMAN_TABLE_BITS));
++ *bits = BROTLI_HC_FAST_LOAD_BITS(table);
++ *value = BROTLI_HC_FAST_LOAD_VALUE(table);
+ }
+
+ /* Decodes the next Huffman code using data prepared by PreloadSymbol.
+@@ -441,10 +448,11 @@ static BROTLI_INLINE uint32_t ReadPreloadedSymbol(const HuffmanCode* table,
+ uint32_t val = BrotliGet16BitsUnmasked(br);
+ const HuffmanCode* ext = table + (val & HUFFMAN_TABLE_MASK) + *value;
+ uint32_t mask = BitMask((*bits - HUFFMAN_TABLE_BITS));
++ BROTLI_HC_MARK_TABLE_FOR_FAST_LOAD(ext);
+ BrotliDropBits(br, HUFFMAN_TABLE_BITS);
+- ext += (val >> HUFFMAN_TABLE_BITS) & mask;
+- BrotliDropBits(br, ext->bits);
+- result = ext->value;
++ BROTLI_HC_ADJUST_TABLE_INDEX(ext, (val >> HUFFMAN_TABLE_BITS) & mask);
++ BrotliDropBits(br, BROTLI_HC_FAST_LOAD_BITS(ext));
++ result = BROTLI_HC_FAST_LOAD_VALUE(ext);
+ } else {
+ BrotliDropBits(br, *bits);
+ }
+@@ -465,32 +473,34 @@ static BROTLI_INLINE uint32_t Log2Floor(uint32_t x) {
+ Totally 1..4 symbols are read, 1..11 bits each.
+ The list of symbols MUST NOT contain duplicates. */
+ static BrotliDecoderErrorCode ReadSimpleHuffmanSymbols(
+- uint32_t alphabet_size, uint32_t max_symbol, BrotliDecoderState* s) {
++ uint32_t alphabet_size_max, uint32_t alphabet_size_limit,
++ BrotliDecoderState* s) {
+ /* max_bits == 1..11; symbol == 0..3; 1..44 bits will be read. */
+ BrotliBitReader* br = &s->br;
+- uint32_t max_bits = Log2Floor(alphabet_size - 1);
+- uint32_t i = s->sub_loop_counter;
+- uint32_t num_symbols = s->symbol;
++ BrotliMetablockHeaderArena* h = &s->arena.header;
++ uint32_t max_bits = Log2Floor(alphabet_size_max - 1);
++ uint32_t i = h->sub_loop_counter;
++ uint32_t num_symbols = h->symbol;
+ while (i <= num_symbols) {
+ uint32_t v;
+ if (BROTLI_PREDICT_FALSE(!BrotliSafeReadBits(br, max_bits, &v))) {
+- s->sub_loop_counter = i;
+- s->substate_huffman = BROTLI_STATE_HUFFMAN_SIMPLE_READ;
++ h->sub_loop_counter = i;
++ h->substate_huffman = BROTLI_STATE_HUFFMAN_SIMPLE_READ;
+ return BROTLI_DECODER_NEEDS_MORE_INPUT;
+ }
+- if (v >= max_symbol) {
++ if (v >= alphabet_size_limit) {
+ return
+ BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_SIMPLE_HUFFMAN_ALPHABET);
+ }
+- s->symbols_lists_array[i] = (uint16_t)v;
+- BROTLI_LOG_UINT(s->symbols_lists_array[i]);
++ h->symbols_lists_array[i] = (uint16_t)v;
++ BROTLI_LOG_UINT(h->symbols_lists_array[i]);
+ ++i;
+ }
+
+ for (i = 0; i < num_symbols; ++i) {
+ uint32_t k = i + 1;
+ for (; k <= num_symbols; ++k) {
+- if (s->symbols_lists_array[i] == s->symbols_lists_array[k]) {
++ if (h->symbols_lists_array[i] == h->symbols_lists_array[k]) {
+ return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_SIMPLE_HUFFMAN_SAME);
+ }
+ }
+@@ -583,33 +593,35 @@ static BROTLI_INLINE void ProcessRepeatedCodeLength(uint32_t code_len,
+ static BrotliDecoderErrorCode ReadSymbolCodeLengths(
+ uint32_t alphabet_size, BrotliDecoderState* s) {
+ BrotliBitReader* br = &s->br;
+- uint32_t symbol = s->symbol;
+- uint32_t repeat = s->repeat;
+- uint32_t space = s->space;
+- uint32_t prev_code_len = s->prev_code_len;
+- uint32_t repeat_code_len = s->repeat_code_len;
+- uint16_t* symbol_lists = s->symbol_lists;
+- uint16_t* code_length_histo = s->code_length_histo;
+- int* next_symbol = s->next_symbol;
++ BrotliMetablockHeaderArena* h = &s->arena.header;
++ uint32_t symbol = h->symbol;
++ uint32_t repeat = h->repeat;
++ uint32_t space = h->space;
++ uint32_t prev_code_len = h->prev_code_len;
++ uint32_t repeat_code_len = h->repeat_code_len;
++ uint16_t* symbol_lists = h->symbol_lists;
++ uint16_t* code_length_histo = h->code_length_histo;
++ int* next_symbol = h->next_symbol;
+ if (!BrotliWarmupBitReader(br)) {
+ return BROTLI_DECODER_NEEDS_MORE_INPUT;
+ }
+ while (symbol < alphabet_size && space > 0) {
+- const HuffmanCode* p = s->table;
++ const HuffmanCode* p = h->table;
+ uint32_t code_len;
++ BROTLI_HC_MARK_TABLE_FOR_FAST_LOAD(p);
+ if (!BrotliCheckInputAmount(br, BROTLI_SHORT_FILL_BIT_WINDOW_READ)) {
+- s->symbol = symbol;
+- s->repeat = repeat;
+- s->prev_code_len = prev_code_len;
+- s->repeat_code_len = repeat_code_len;
+- s->space = space;
++ h->symbol = symbol;
++ h->repeat = repeat;
++ h->prev_code_len = prev_code_len;
++ h->repeat_code_len = repeat_code_len;
++ h->space = space;
+ return BROTLI_DECODER_NEEDS_MORE_INPUT;
+ }
+ BrotliFillBitWindow16(br);
+- p += BrotliGetBitsUnmasked(br) &
+- BitMask(BROTLI_HUFFMAN_MAX_CODE_LENGTH_CODE_LENGTH);
+- BrotliDropBits(br, p->bits); /* Use 1..5 bits. */
+- code_len = p->value; /* code_len == 0..17 */
++ BROTLI_HC_ADJUST_TABLE_INDEX(p, BrotliGetBitsUnmasked(br) &
++ BitMask(BROTLI_HUFFMAN_MAX_CODE_LENGTH_CODE_LENGTH));
++ BrotliDropBits(br, BROTLI_HC_FAST_LOAD_BITS(p)); /* Use 1..5 bits. */
++ code_len = BROTLI_HC_FAST_LOAD_VALUE(p); /* code_len == 0..17 */
+ if (code_len < BROTLI_REPEAT_PREVIOUS_CODE_LENGTH) {
+ ProcessSingleCodeLength(code_len, &symbol, &repeat, &space,
+ &prev_code_len, symbol_lists, code_length_histo, next_symbol);
+@@ -624,48 +636,52 @@ static BrotliDecoderErrorCode ReadSymbolCodeLengths(
+ symbol_lists, code_length_histo, next_symbol);
+ }
+ }
+- s->space = space;
++ h->space = space;
+ return BROTLI_DECODER_SUCCESS;
+ }
+
+ static BrotliDecoderErrorCode SafeReadSymbolCodeLengths(
+ uint32_t alphabet_size, BrotliDecoderState* s) {
+ BrotliBitReader* br = &s->br;
++ BrotliMetablockHeaderArena* h = &s->arena.header;
+ BROTLI_BOOL get_byte = BROTLI_FALSE;
+- while (s->symbol < alphabet_size && s->space > 0) {
+- const HuffmanCode* p = s->table;
++ while (h->symbol < alphabet_size && h->space > 0) {
++ const HuffmanCode* p = h->table;
+ uint32_t code_len;
+ uint32_t available_bits;
+ uint32_t bits = 0;
++ BROTLI_HC_MARK_TABLE_FOR_FAST_LOAD(p);
+ if (get_byte && !BrotliPullByte(br)) return BROTLI_DECODER_NEEDS_MORE_INPUT;
+ get_byte = BROTLI_FALSE;
+ available_bits = BrotliGetAvailableBits(br);
+ if (available_bits != 0) {
+ bits = (uint32_t)BrotliGetBitsUnmasked(br);
+ }
+- p += bits & BitMask(BROTLI_HUFFMAN_MAX_CODE_LENGTH_CODE_LENGTH);
+- if (p->bits > available_bits) {
++ BROTLI_HC_ADJUST_TABLE_INDEX(p,
++ bits & BitMask(BROTLI_HUFFMAN_MAX_CODE_LENGTH_CODE_LENGTH));
++ if (BROTLI_HC_FAST_LOAD_BITS(p) > available_bits) {
+ get_byte = BROTLI_TRUE;
+ continue;
+ }
+- code_len = p->value; /* code_len == 0..17 */
++ code_len = BROTLI_HC_FAST_LOAD_VALUE(p); /* code_len == 0..17 */
+ if (code_len < BROTLI_REPEAT_PREVIOUS_CODE_LENGTH) {
+- BrotliDropBits(br, p->bits);
+- ProcessSingleCodeLength(code_len, &s->symbol, &s->repeat, &s->space,
+- &s->prev_code_len, s->symbol_lists, s->code_length_histo,
+- s->next_symbol);
++ BrotliDropBits(br, BROTLI_HC_FAST_LOAD_BITS(p));
++ ProcessSingleCodeLength(code_len, &h->symbol, &h->repeat, &h->space,
++ &h->prev_code_len, h->symbol_lists, h->code_length_histo,
++ h->next_symbol);
+ } else { /* code_len == 16..17, extra_bits == 2..3 */
+ uint32_t extra_bits = code_len - 14U;
+- uint32_t repeat_delta = (bits >> p->bits) & BitMask(extra_bits);
+- if (available_bits < p->bits + extra_bits) {
++ uint32_t repeat_delta = (bits >> BROTLI_HC_FAST_LOAD_BITS(p)) &
++ BitMask(extra_bits);
++ if (available_bits < BROTLI_HC_FAST_LOAD_BITS(p) + extra_bits) {
+ get_byte = BROTLI_TRUE;
+ continue;
+ }
+- BrotliDropBits(br, p->bits + extra_bits);
++ BrotliDropBits(br, BROTLI_HC_FAST_LOAD_BITS(p) + extra_bits);
+ ProcessRepeatedCodeLength(code_len, repeat_delta, alphabet_size,
+- &s->symbol, &s->repeat, &s->space, &s->prev_code_len,
+- &s->repeat_code_len, s->symbol_lists, s->code_length_histo,
+- s->next_symbol);
++ &h->symbol, &h->repeat, &h->space, &h->prev_code_len,
++ &h->repeat_code_len, h->symbol_lists, h->code_length_histo,
++ h->next_symbol);
+ }
+ }
+ return BROTLI_DECODER_SUCCESS;
+@@ -675,9 +691,10 @@ static BrotliDecoderErrorCode SafeReadSymbolCodeLengths(
+ Each code is 2..4 bits long. In total 30..72 bits are used. */
+ static BrotliDecoderErrorCode ReadCodeLengthCodeLengths(BrotliDecoderState* s) {
+ BrotliBitReader* br = &s->br;
+- uint32_t num_codes = s->repeat;
+- unsigned space = s->space;
+- uint32_t i = s->sub_loop_counter;
++ BrotliMetablockHeaderArena* h = &s->arena.header;
++ uint32_t num_codes = h->repeat;
++ unsigned space = h->space;
++ uint32_t i = h->sub_loop_counter;
+ for (; i < BROTLI_CODE_LENGTH_CODES; ++i) {
+ const uint8_t code_len_idx = kCodeLengthCodeOrder[i];
+ uint32_t ix;
+@@ -690,21 +707,21 @@ static BrotliDecoderErrorCode ReadCodeLengthCodeLengths(BrotliDecoderState* s) {
+ ix = 0;
+ }
+ if (kCodeLengthPrefixLength[ix] > available_bits) {
+- s->sub_loop_counter = i;
+- s->repeat = num_codes;
+- s->space = space;
+- s->substate_huffman = BROTLI_STATE_HUFFMAN_COMPLEX;
++ h->sub_loop_counter = i;
++ h->repeat = num_codes;
++ h->space = space;
++ h->substate_huffman = BROTLI_STATE_HUFFMAN_COMPLEX;
+ return BROTLI_DECODER_NEEDS_MORE_INPUT;
+ }
+ }
+ v = kCodeLengthPrefixValue[ix];
+ BrotliDropBits(br, kCodeLengthPrefixLength[ix]);
+- s->code_length_code_lengths[code_len_idx] = (uint8_t)v;
+- BROTLI_LOG_ARRAY_INDEX(s->code_length_code_lengths, code_len_idx);
++ h->code_length_code_lengths[code_len_idx] = (uint8_t)v;
++ BROTLI_LOG_ARRAY_INDEX(h->code_length_code_lengths, code_len_idx);
+ if (v != 0) {
+ space = space - (32U >> v);
+ ++num_codes;
+- ++s->code_length_histo[v];
++ ++h->code_length_histo[v];
+ if (space - 1U >= 32U) {
+ /* space is 0 or wrapped around. */
+ break;
+@@ -728,49 +745,48 @@ static BrotliDecoderErrorCode ReadCodeLengthCodeLengths(BrotliDecoderState* s) {
+ encoded with predefined entropy code. 32 - 74 bits are used.
+ B.2) Decoded table is used to decode code lengths of symbols in resulting
+ Huffman table. In worst case 3520 bits are read. */
+-static BrotliDecoderErrorCode ReadHuffmanCode(uint32_t alphabet_size,
+- uint32_t max_symbol,
++static BrotliDecoderErrorCode ReadHuffmanCode(uint32_t alphabet_size_max,
++ uint32_t alphabet_size_limit,
+ HuffmanCode* table,
+ uint32_t* opt_table_size,
+ BrotliDecoderState* s) {
+ BrotliBitReader* br = &s->br;
+- /* Unnecessary masking, but might be good for safety. */
+- alphabet_size &= 0x7FF;
++ BrotliMetablockHeaderArena* h = &s->arena.header;
+ /* State machine. */
+ for (;;) {
+- switch (s->substate_huffman) {
++ switch (h->substate_huffman) {
+ case BROTLI_STATE_HUFFMAN_NONE:
+- if (!BrotliSafeReadBits(br, 2, &s->sub_loop_counter)) {
++ if (!BrotliSafeReadBits(br, 2, &h->sub_loop_counter)) {
+ return BROTLI_DECODER_NEEDS_MORE_INPUT;
+ }
+- BROTLI_LOG_UINT(s->sub_loop_counter);
++ BROTLI_LOG_UINT(h->sub_loop_counter);
+ /* The value is used as follows:
+ 1 for simple code;
+ 0 for no skipping, 2 skips 2 code lengths, 3 skips 3 code lengths */
+- if (s->sub_loop_counter != 1) {
+- s->space = 32;
+- s->repeat = 0; /* num_codes */
+- memset(&s->code_length_histo[0], 0, sizeof(s->code_length_histo[0]) *
++ if (h->sub_loop_counter != 1) {
++ h->space = 32;
++ h->repeat = 0; /* num_codes */
++ memset(&h->code_length_histo[0], 0, sizeof(h->code_length_histo[0]) *
+ (BROTLI_HUFFMAN_MAX_CODE_LENGTH_CODE_LENGTH + 1));
+- memset(&s->code_length_code_lengths[0], 0,
+- sizeof(s->code_length_code_lengths));
+- s->substate_huffman = BROTLI_STATE_HUFFMAN_COMPLEX;
++ memset(&h->code_length_code_lengths[0], 0,
++ sizeof(h->code_length_code_lengths));
++ h->substate_huffman = BROTLI_STATE_HUFFMAN_COMPLEX;
+ continue;
+ }
+ /* Fall through. */
+
+ case BROTLI_STATE_HUFFMAN_SIMPLE_SIZE:
+ /* Read symbols, codes & code lengths directly. */
+- if (!BrotliSafeReadBits(br, 2, &s->symbol)) { /* num_symbols */
+- s->substate_huffman = BROTLI_STATE_HUFFMAN_SIMPLE_SIZE;
++ if (!BrotliSafeReadBits(br, 2, &h->symbol)) { /* num_symbols */
++ h->substate_huffman = BROTLI_STATE_HUFFMAN_SIMPLE_SIZE;
+ return BROTLI_DECODER_NEEDS_MORE_INPUT;
+ }
+- s->sub_loop_counter = 0;
++ h->sub_loop_counter = 0;
+ /* Fall through. */
+
+ case BROTLI_STATE_HUFFMAN_SIMPLE_READ: {
+ BrotliDecoderErrorCode result =
+- ReadSimpleHuffmanSymbols(alphabet_size, max_symbol, s);
++ ReadSimpleHuffmanSymbols(alphabet_size_max, alphabet_size_limit, s);
+ if (result != BROTLI_DECODER_SUCCESS) {
+ return result;
+ }
+@@ -779,21 +795,21 @@ static BrotliDecoderErrorCode ReadHuffmanCode(uint32_t alphabet_size,
+
+ case BROTLI_STATE_HUFFMAN_SIMPLE_BUILD: {
+ uint32_t table_size;
+- if (s->symbol == 3) {
++ if (h->symbol == 3) {
+ uint32_t bits;
+ if (!BrotliSafeReadBits(br, 1, &bits)) {
+- s->substate_huffman = BROTLI_STATE_HUFFMAN_SIMPLE_BUILD;
++ h->substate_huffman = BROTLI_STATE_HUFFMAN_SIMPLE_BUILD;
+ return BROTLI_DECODER_NEEDS_MORE_INPUT;
+ }
+- s->symbol += bits;
++ h->symbol += bits;
+ }
+- BROTLI_LOG_UINT(s->symbol);
++ BROTLI_LOG_UINT(h->symbol);
+ table_size = BrotliBuildSimpleHuffmanTable(
+- table, HUFFMAN_TABLE_BITS, s->symbols_lists_array, s->symbol);
++ table, HUFFMAN_TABLE_BITS, h->symbols_lists_array, h->symbol);
+ if (opt_table_size) {
+ *opt_table_size = table_size;
+ }
+- s->substate_huffman = BROTLI_STATE_HUFFMAN_NONE;
++ h->substate_huffman = BROTLI_STATE_HUFFMAN_NONE;
+ return BROTLI_DECODER_SUCCESS;
+ }
+
+@@ -804,44 +820,45 @@ static BrotliDecoderErrorCode ReadHuffmanCode(uint32_t alphabet_size,
+ if (result != BROTLI_DECODER_SUCCESS) {
+ return result;
+ }
+- BrotliBuildCodeLengthsHuffmanTable(s->table,
+- s->code_length_code_lengths,
+- s->code_length_histo);
+- memset(&s->code_length_histo[0], 0, sizeof(s->code_length_histo));
++ BrotliBuildCodeLengthsHuffmanTable(h->table,
++ h->code_length_code_lengths,
++ h->code_length_histo);
++ memset(&h->code_length_histo[0], 0, sizeof(h->code_length_histo));
+ for (i = 0; i <= BROTLI_HUFFMAN_MAX_CODE_LENGTH; ++i) {
+- s->next_symbol[i] = (int)i - (BROTLI_HUFFMAN_MAX_CODE_LENGTH + 1);
+- s->symbol_lists[s->next_symbol[i]] = 0xFFFF;
++ h->next_symbol[i] = (int)i - (BROTLI_HUFFMAN_MAX_CODE_LENGTH + 1);
++ h->symbol_lists[h->next_symbol[i]] = 0xFFFF;
+ }
+
+- s->symbol = 0;
+- s->prev_code_len = BROTLI_INITIAL_REPEATED_CODE_LENGTH;
+- s->repeat = 0;
+- s->repeat_code_len = 0;
+- s->space = 32768;
+- s->substate_huffman = BROTLI_STATE_HUFFMAN_LENGTH_SYMBOLS;
++ h->symbol = 0;
++ h->prev_code_len = BROTLI_INITIAL_REPEATED_CODE_LENGTH;
++ h->repeat = 0;
++ h->repeat_code_len = 0;
++ h->space = 32768;
++ h->substate_huffman = BROTLI_STATE_HUFFMAN_LENGTH_SYMBOLS;
+ }
+ /* Fall through. */
+
+ case BROTLI_STATE_HUFFMAN_LENGTH_SYMBOLS: {
+ uint32_t table_size;
+- BrotliDecoderErrorCode result = ReadSymbolCodeLengths(max_symbol, s);
++ BrotliDecoderErrorCode result = ReadSymbolCodeLengths(
++ alphabet_size_limit, s);
+ if (result == BROTLI_DECODER_NEEDS_MORE_INPUT) {
+- result = SafeReadSymbolCodeLengths(max_symbol, s);
++ result = SafeReadSymbolCodeLengths(alphabet_size_limit, s);
+ }
+ if (result != BROTLI_DECODER_SUCCESS) {
+ return result;
+ }
+
+- if (s->space != 0) {
+- BROTLI_LOG(("[ReadHuffmanCode] space = %d\n", (int)s->space));
++ if (h->space != 0) {
++ BROTLI_LOG(("[ReadHuffmanCode] space = %d\n", (int)h->space));
+ return BROTLI_FAILURE(BROTLI_DECODER_ERROR_FORMAT_HUFFMAN_SPACE);
+ }
+ table_size = BrotliBuildHuffmanTable(
+- table, HUFFMAN_TABLE_BITS, s->symbol_lists, s->code_length_histo);
++ table, HUFFMAN_TABLE_BITS, h->symbol_lists, h->code_length_histo);
+ if (opt_table_size) {
+ *opt_table_size = table_size;
+ }
+- s->substate_huffman = BROTLI_STATE_HUFFMAN_NONE;
++ h->substate_huffman = BROTLI_STATE_HUFFMAN_NONE;
+ return BROTLI_DECODER_SUCCESS;
+ }
+
+@@ -858,8 +875,8 @@ static BROTLI_INLINE uint32_t ReadBlockLength(const HuffmanCode* table,
+ uint32_t code;
+ uint32_t nbits;
+ code = ReadSymbol(table, br);
+- nbits = kBlockLengthPrefixCode[code].nbits; /* nbits == 2..24 */
+- return kBlockLengthPrefixCode[code].offset + BrotliReadBits(br, nbits);
++ nbits = _kBrotliPrefixCodeRanges[code].nbits; /* nbits == 2..24 */
++ return _kBrotliPrefixCodeRanges[code].offset + BrotliReadBits24(br, nbits);
+ }
+
+ /* WARNING: if state is not BROTLI_STATE_READ_BLOCK_LENGTH_NONE, then
+@@ -877,13 +894,14 @@ static BROTLI_INLINE BROTLI_BOOL SafeReadBlockLength(
+ }
+ {
+ uint32_t bits;
+- uint32_t nbits = kBlockLengthPrefixCode[index].nbits; /* nbits == 2..24 */
++ uint32_t nbits = _kBrotliPrefixCodeRanges[index].nbits;
++ uint32_t offset = _kBrotliPrefixCodeRanges[index].offset;
+ if (!BrotliSafeReadBits(br, nbits, &bits)) {
+ s->block_length_index = index;
+ s->substate_read_block_length = BROTLI_STATE_READ_BLOCK_LENGTH_SUFFIX;
+ return BROTLI_FALSE;
+ }
+- *result = kBlockLengthPrefixCode[index].offset + bits;
++ *result = offset + bits;
+ s->substate_read_block_length = BROTLI_STATE_READ_BLOCK_LENGTH_NONE;
+ return BROTLI_TRUE;
+ }
+@@ -943,22 +961,22 @@ static BROTLI_NOINLINE void InverseMoveToFrontTransform(
+ /* Decodes a series of Huffman table using ReadHuffmanCode function. */
+ static BrotliDecoderErrorCode HuffmanTreeGroupDecode(
+ HuffmanTreeGroup* group, BrotliDecoderState* s) {
+- if (s->substate_tree_group != BROTLI_STATE_TREE_GROUP_LOOP) {
+- s->next = group->codes;
+- s->htree_index = 0;
+- s->substate_tree_group = BROTLI_STATE_TREE_GROUP_LOOP;
++ BrotliMetablockHeaderArena* h = &s->arena.header;
++ if (h->substate_tree_group != BROTLI_STATE_TREE_GROUP_LOOP) {
++ h->next = group->codes;
++ h->htree_index = 0;
++ h->substate_tree_group = BROTLI_STATE_TREE_GROUP_LOOP;
+ }
+- while (s->htree_index < group->num_htrees) {
++ while (h->htree_index < group->num_htrees) {
+ uint32_t table_size;
+- BrotliDecoderErrorCode result =
+- ReadHuffmanCode(group->alphabet_size, group->max_symbol,
+- s->next, &table_size, s);
++ BrotliDecoderErrorCode result = ReadHuffmanCode(group->alphabet_size_max,
++ group->alphabet_size_limit, h->next, &table_size, s);
+ if (result != BROTLI_DECODER_SUCCESS) return result;
+- group->htrees[s->htree_index] = s->next;
+- s->next += table_size;
+- ++s->htree_index;
++ group->htrees[h->htree_index] = h->next;
++ h->next += table_size;
++ ++h->htree_index;
+ }
+- s->substate_tree_group = BROTLI_STATE_TREE_GROUP_NONE;
++ h->substate_tree_group = BROTLI_STATE_TREE_GROUP_NONE;
+ return BROTLI_DECODER_SUCCESS;
+ }
+
+@@ -976,15 +994,16 @@ static BrotliDecoderErrorCode DecodeContextMap(uint32_t context_map_size,
+ BrotliDecoderState* s) {
+ BrotliBitReader* br = &s->br;
+ BrotliDecoderErrorCode result = BROTLI_DECODER_SUCCESS;
++ BrotliMetablockHeaderArena* h = &s->arena.header;
+
+- switch ((int)s->substate_context_map) {
++ switch ((int)h->substate_context_map) {
+ case BROTLI_STATE_CONTEXT_MAP_NONE:
+ result = DecodeVarLenUint8(s, br, num_htrees);
+ if (result != BROTLI_DECODER_SUCCESS) {
+ return result;
+ }
+ (*num_htrees)++;
+- s->context_index = 0;
++ h->context_index = 0;
+ BROTLI_LOG_UINT(context_map_size);
+ BROTLI_LOG_UINT(*num_htrees);
+ *context_map_arg =
+@@ -996,7 +1015,7 @@ static BrotliDecoderErrorCode DecodeContextMap(uint32_t context_map_size,
+ memset(*context_map_arg, 0, (size_t)context_map_size);
+ return BROTLI_DECODER_SUCCESS;
+ }
+- s->substate_context_map = BROTLI_STATE_CONTEXT_MAP_READ_PREFIX;
++ h->substate_context_map = BROTLI_STATE_CONTEXT_MAP_READ_PREFIX;
+ /* Fall through. */
+
+ case BROTLI_STATE_CONTEXT_MAP_READ_PREFIX: {
+@@ -1007,38 +1026,38 @@ static BrotliDecoderErrorCode DecodeContextMap(uint32_t context_map_size,
+ return BROTLI_DECODER_NEEDS_MORE_INPUT;
+ }
+ if ((bits & 1) != 0) { /* Use RLE for zeros. */
+- s->max_run_length_prefix = (bits >> 1) + 1;
++ h->max_run_length_prefix = (bits >> 1) + 1;
+ BrotliDropBits(br, 5);
+ } else {
+- s->max_run_length_prefix = 0;
++ h->max_run_length_prefix = 0;
+ BrotliDropBits(br, 1);
+ }
+- BROTLI_LOG_UINT(s->max_run_length_prefix);
+- s->substate_context_map = BROTLI_STATE_CONTEXT_MAP_HUFFMAN;
++ BROTLI_LOG_UINT(h->max_run_length_prefix);
++ h->substate_context_map = BROTLI_STATE_CONTEXT_MAP_HUFFMAN;
+ }
+ /* Fall through. */
+
+ case BROTLI_STATE_CONTEXT_MAP_HUFFMAN: {
+- uint32_t alphabet_size = *num_htrees + s->max_run_length_prefix;
++ uint32_t alphabet_size = *num_htrees + h->max_run_length_prefix;
+ result = ReadHuffmanCode(alphabet_size, alphabet_size,
+- s->context_map_table, NULL, s);
++ h->context_map_table, NULL, s);
+ if (result != BROTLI_DECODER_SUCCESS) return result;
+- s->code = 0xFFFF;
+- s->substate_context_map = BROTLI_STATE_CONTEXT_MAP_DECODE;
++ h->code = 0xFFFF;
++ h->substate_context_map = BROTLI_STATE_CONTEXT_MAP_DECODE;
+ }
+ /* Fall through. */
+
+ case BROTLI_STATE_CONTEXT_MAP_DECODE: {
+- uint32_t context_index = s->context_index;
+- uint32_t max_run_length_prefix = s->max_run_length_prefix;
++ uint32_t context_index = h->context_index;
++ uint32_t max_run_length_prefix = h->max_run_length_prefix;
+ uint8_t* context_map = *context_map_arg;
+- uint32_t code = s->code;
++ uint32_t code = h->code;
+ BROTLI_BOOL skip_preamble = (code != 0xFFFF);
+ while (context_index < context_map_size || skip_preamble) {
+ if (!skip_preamble) {
+- if (!SafeReadSymbol(s->context_map_table, br, &code)) {
+- s->code = 0xFFFF;
+- s->context_index = context_index;
++ if (!SafeReadSymbol(h->context_map_table, br, &code)) {
++ h->code = 0xFFFF;
++ h->context_index = context_index;
+ return BROTLI_DECODER_NEEDS_MORE_INPUT;
+ }
+ BROTLI_LOG_UINT(code);
+@@ -1059,8 +1078,8 @@ static BrotliDecoderErrorCode DecodeContextMap(uint32_t context_map_size,
+ {
+ uint32_t reps;
+ if (!BrotliSafeReadBits(br, code, &reps)) {
+- s->code = code;
+- s->context_index = context_index;
++ h->code = code;
++ h->context_index = context_index;
+ return BROTLI_DECODER_NEEDS_MORE_INPUT;
+ }
+ reps += 1U << code;
+@@ -1080,13 +1099,13 @@ static BrotliDecoderErrorCode DecodeContextMap(uint32_t context_map_size,
+ case BROTLI_STATE_CONTEXT_MAP_TRANSFORM: {
+ uint32_t bits;
+ if (!BrotliSafeReadBits(br, 1, &bits)) {
+- s->substate_context_map = BROTLI_STATE_CONTEXT_MAP_TRANSFORM;
++ h->substate_context_map = BROTLI_STATE_CONTEXT_MAP_TRANSFORM;
+ return BROTLI_DECODER_NEEDS_MORE_INPUT;
+ }
+ if (bits != 0) {
+ InverseMoveToFrontTransform(*context_map_arg, context_map_size, s);
+ }
+- s->substate_context_map = BROTLI_STATE_CONTEXT_MAP_NONE;
++ h->substate_context_map = BROTLI_STATE_CONTEXT_MAP_NONE;
+ return BROTLI_DECODER_SUCCESS;
+ }
+
+@@ -1448,32 +1467,28 @@ static BrotliDecoderErrorCode ReadContextModes(BrotliDecoderState* s) {
+ }
+
+ static BROTLI_INLINE void TakeDistanceFromRingBuffer(BrotliDecoderState* s) {
+- if (s->distance_code == 0) {
+- --s->dist_rb_idx;
+- s->distance_code = s->dist_rb[s->dist_rb_idx & 3];
++ int offset = s->distance_code - 3;
++ if (s->distance_code <= 3) {
+ /* Compensate double distance-ring-buffer roll for dictionary items. */
+- s->distance_context = 1;
++ s->distance_context = 1 >> s->distance_code;
++ s->distance_code = s->dist_rb[(s->dist_rb_idx - offset) & 3];
++ s->dist_rb_idx -= s->distance_context;
+ } else {
+- int distance_code = s->distance_code << 1;
+- /* kDistanceShortCodeIndexOffset has 2-bit values from LSB:
+- 3, 2, 1, 0, 3, 3, 3, 3, 3, 3, 2, 2, 2, 2, 2, 2 */
+- const uint32_t kDistanceShortCodeIndexOffset = 0xAAAFFF1B;
+- /* kDistanceShortCodeValueOffset has 2-bit values from LSB:
+- -0, 0,-0, 0,-1, 1,-2, 2,-3, 3,-1, 1,-2, 2,-3, 3 */
+- const uint32_t kDistanceShortCodeValueOffset = 0xFA5FA500;
+- int v = (s->dist_rb_idx +
+- (int)(kDistanceShortCodeIndexOffset >> distance_code)) & 0x3;
+- s->distance_code = s->dist_rb[v];
+- v = (int)(kDistanceShortCodeValueOffset >> distance_code) & 0x3;
+- if ((distance_code & 0x3) != 0) {
+- s->distance_code += v;
++ int index_delta = 3;
++ int delta;
++ int base = s->distance_code - 10;
++ if (s->distance_code < 10) {
++ base = s->distance_code - 4;
+ } else {
+- s->distance_code -= v;
+- if (s->distance_code <= 0) {
+- /* A huge distance will cause a BROTLI_FAILURE() soon.
+- This is a little faster than failing here. */
+- s->distance_code = 0x7FFFFFFF;
+- }
++ index_delta = 2;
++ }
++ /* Unpack one of six 4-bit values. */
++ delta = ((0x605142 >> (4 * base)) & 0xF) - 3;
++ s->distance_code = s->dist_rb[(s->dist_rb_idx + index_delta) & 0x3] + delta;
++ if (s->distance_code <= 0) {
++ /* A huge distance will cause a BROTLI_FAILURE() soon.
++ This is a little faster than failing here. */
++ s->distance_code = 0x7FFFFFFF;
+ }
+ }
+ }
+@@ -1488,62 +1503,153 @@ static BROTLI_INLINE BROTLI_BOOL SafeReadBits(
+ }
+ }
+
++static BROTLI_INLINE BROTLI_BOOL SafeReadBits32(
++ BrotliBitReader* const br, uint32_t n_bits, uint32_t* val) {
++ if (n_bits != 0) {
++ return BrotliSafeReadBits32(br, n_bits, val);
++ } else {
++ *val = 0;
++ return BROTLI_TRUE;
++ }
++}
++
++/*
++ RFC 7932 Section 4 with "..." shortenings and "[]" emendations.
++
++ Each distance ... is represented with a pair <distance code, extra bits>...
++ The distance code is encoded using a prefix code... The number of extra bits
++ can be 0..24... Two additional parameters: NPOSTFIX (0..3), and ...
++ NDIRECT (0..120) ... are encoded in the meta-block header...
++
++ The first 16 distance symbols ... reference past distances... ring buffer ...
++ Next NDIRECT distance symbols ... represent distances from 1 to NDIRECT...
++ [For] distance symbols 16 + NDIRECT and greater ... the number of extra bits
++ ... is given by the following formula:
++
++ [ xcode = dcode - NDIRECT - 16 ]
++ ndistbits = 1 + [ xcode ] >> (NPOSTFIX + 1)
++
++ ...
++*/
++
++/*
++ RFC 7932 Section 9.2 with "..." shortenings and "[]" emendations.
++
++ ... to get the actual value of the parameter NDIRECT, left-shift this
++ four-bit number by NPOSTFIX bits ...
++*/
++
++/* Remaining formulas from RFC 7932 Section 4 could be rewritten as following:
++
++ alphabet_size = 16 + NDIRECT + (max_distbits << (NPOSTFIX + 1))
++
++ half = ((xcode >> NPOSTFIX) & 1) << ndistbits
++ postfix = xcode & ((1 << NPOSTFIX) - 1)
++ range_start = 2 * (1 << ndistbits - 1 - 1)
++
++ distance = (range_start + half + extra) << NPOSTFIX + postfix + NDIRECT + 1
++
++ NB: ndistbits >= 1 -> range_start >= 0
++ NB: range_start has factor 2, as the range is covered by 2 "halves"
++ NB: extra -1 offset in range_start formula covers the absence of
++ ndistbits = 0 case
++ NB: when NPOSTFIX = 0, NDIRECT is not greater than 15
++
++ In other words, xcode has the following binary structure - XXXHPPP:
++ - XXX represent the number of extra distance bits
++ - H selects upper / lower range of distances
++ - PPP represent "postfix"
++
++ "Regular" distance encoding has NPOSTFIX = 0; omitting the postfix part
++ simplifies distance calculation.
++
++ Using NPOSTFIX > 0 allows cheaper encoding of regular structures, e.g. where
++ most of distances have the same reminder of division by 2/4/8. For example,
++ the table of int32_t values that come from different sources; if it is likely
++ that 3 highest bytes of values from the same source are the same, then
++ copy distance often looks like 4x + y.
++
++ Distance calculation could be rewritten to:
++
++ ndistbits = NDISTBITS(NDIRECT, NPOSTFIX)[dcode]
++ distance = OFFSET(NDIRECT, NPOSTFIX)[dcode] + extra << NPOSTFIX
++
++ NDISTBITS and OFFSET could be pre-calculated, as NDIRECT and NPOSTFIX could
++ change only once per meta-block.
++*/
++
++/* Calculates distance lookup table.
++ NB: it is possible to have all 64 tables precalculated. */
++static void CalculateDistanceLut(BrotliDecoderState* s) {
++ BrotliMetablockBodyArena* b = &s->arena.body;
++ uint32_t npostfix = s->distance_postfix_bits;
++ uint32_t ndirect = s->num_direct_distance_codes;
++ uint32_t alphabet_size_limit = s->distance_hgroup.alphabet_size_limit;
++ uint32_t postfix = 1u << npostfix;
++ uint32_t j;
++ uint32_t bits = 1;
++ uint32_t half = 0;
++
++ /* Skip short codes. */
++ uint32_t i = BROTLI_NUM_DISTANCE_SHORT_CODES;
++
++ /* Fill direct codes. */
++ for (j = 0; j < ndirect; ++j) {
++ b->dist_extra_bits[i] = 0;
++ b->dist_offset[i] = j + 1;
++ ++i;
++ }
++
++ /* Fill regular distance codes. */
++ while (i < alphabet_size_limit) {
++ uint32_t base = ndirect + ((((2 + half) << bits) - 4) << npostfix) + 1;
++ /* Always fill the complete group. */
++ for (j = 0; j < postfix; ++j) {
++ b->dist_extra_bits[i] = (uint8_t)bits;
++ b->dist_offset[i] = base + j;
++ ++i;
++ }
++ bits = bits + half;
++ half = half ^ 1;
++ }
++}
++
+ /* Precondition: s->distance_code < 0. */
+ static BROTLI_INLINE BROTLI_BOOL ReadDistanceInternal(
+ int safe, BrotliDecoderState* s, BrotliBitReader* br) {
+- int distval;
++ BrotliMetablockBodyArena* b = &s->arena.body;
++ uint32_t code;
++ uint32_t bits;
+ BrotliBitReaderState memento;
+ HuffmanCode* distance_tree = s->distance_hgroup.htrees[s->dist_htree_index];
+ if (!safe) {
+- s->distance_code = (int)ReadSymbol(distance_tree, br);
++ code = ReadSymbol(distance_tree, br);
+ } else {
+- uint32_t code;
+ BrotliBitReaderSaveState(br, &memento);
+ if (!SafeReadSymbol(distance_tree, br, &code)) {
+ return BROTLI_FALSE;
+ }
+- s->distance_code = (int)code;
+ }
++ --s->block_length[2];
+ /* Convert the distance code to the actual distance by possibly
+- looking up past distances from the s->ringbuffer. */
++ looking up past distances from the s->dist_rb. */
+ s->distance_context = 0;
+- if ((s->distance_code & ~0xF) == 0) {
++ if ((code & ~0xFu) == 0) {
++ s->distance_code = (int)code;
+ TakeDistanceFromRingBuffer(s);
+- --s->block_length[2];
+ return BROTLI_TRUE;
+ }
+- distval = s->distance_code - (int)s->num_direct_distance_codes;
+- if (distval >= 0) {
+- uint32_t nbits;
+- int postfix;
+- int offset;
+- if (!safe && (s->distance_postfix_bits == 0)) {
+- nbits = ((uint32_t)distval >> 1) + 1;
+- offset = ((2 + (distval & 1)) << nbits) - 4;
+- s->distance_code = (int)s->num_direct_distance_codes + offset +
+- (int)BrotliReadBits(br, nbits);
+- } else {
+- /* This branch also works well when s->distance_postfix_bits == 0. */
+- uint32_t bits;
+- postfix = distval & s->distance_postfix_mask;
+- distval >>= s->distance_postfix_bits;
+- nbits = ((uint32_t)distval >> 1) + 1;
+- if (safe) {
+- if (!SafeReadBits(br, nbits, &bits)) {
+- s->distance_code = -1; /* Restore precondition. */
+- BrotliBitReaderRestoreState(br, &memento);
+- return BROTLI_FALSE;
+- }
+- } else {
+- bits = BrotliReadBits(br, nbits);
+- }
+- offset = ((2 + (distval & 1)) << nbits) - 4;
+- s->distance_code = (int)s->num_direct_distance_codes +
+- ((offset + (int)bits) << s->distance_postfix_bits) + postfix;
++ if (!safe) {
++ bits = BrotliReadBits32(br, b->dist_extra_bits[code]);
++ } else {
++ if (!SafeReadBits32(br, b->dist_extra_bits[code], &bits)) {
++ ++s->block_length[2];
++ BrotliBitReaderRestoreState(br, &memento);
++ return BROTLI_FALSE;
+ }
+ }
+- s->distance_code = s->distance_code - BROTLI_NUM_DISTANCE_SHORT_CODES + 1;
+- --s->block_length[2];
++ s->distance_code =
++ (int)(b->dist_offset[code] + (bits << s->distance_postfix_bits));
+ return BROTLI_TRUE;
+ }
+
+@@ -1579,9 +1685,9 @@ static BROTLI_INLINE BROTLI_BOOL ReadCommandInternal(
+ *insert_length = v.insert_len_offset;
+ if (!safe) {
+ if (BROTLI_PREDICT_FALSE(v.insert_len_extra_bits != 0)) {
+- insert_len_extra = BrotliReadBits(br, v.insert_len_extra_bits);
++ insert_len_extra = BrotliReadBits24(br, v.insert_len_extra_bits);
+ }
+- copy_length = BrotliReadBits(br, v.copy_len_extra_bits);
++ copy_length = BrotliReadBits24(br, v.copy_len_extra_bits);
+ } else {
+ if (!SafeReadBits(br, v.insert_len_extra_bits, &insert_len_extra) ||
+ !SafeReadBits(br, v.copy_len_extra_bits, ©_length)) {
+@@ -1926,21 +2032,6 @@ static BROTLI_NOINLINE BrotliDecoderErrorCode SafeProcessCommands(
+ return ProcessCommandsInternal(1, s);
+ }
+
+-/* Returns the maximum number of distance symbols which can only represent
+- distances not exceeding BROTLI_MAX_ALLOWED_DISTANCE. */
+-static uint32_t BrotliMaxDistanceSymbol(uint32_t ndirect, uint32_t npostfix) {
+- static const uint32_t bound[BROTLI_MAX_NPOSTFIX + 1] = {0, 4, 12, 28};
+- static const uint32_t diff[BROTLI_MAX_NPOSTFIX + 1] = {73, 126, 228, 424};
+- uint32_t postfix = 1U << npostfix;
+- if (ndirect < bound[npostfix]) {
+- return ndirect + diff[npostfix] + postfix;
+- } else if (ndirect > bound[npostfix] + postfix) {
+- return ndirect + diff[npostfix];
+- } else {
+- return bound[npostfix] + diff[npostfix] + postfix;
+- }
+-}
+-
+ BrotliDecoderResult BrotliDecoderDecompress(
+ size_t encoded_size, const uint8_t* encoded_buffer, size_t* decoded_size,
+ uint8_t* decoded_buffer) {
+@@ -2158,33 +2249,23 @@ BrotliDecoderResult BrotliDecoderDecompressStream(
+ s->state = BROTLI_STATE_UNCOMPRESSED;
+ break;
+ }
++ s->state = BROTLI_STATE_BEFORE_COMPRESSED_METABLOCK_HEADER;
++ /* Fall through. */
++
++ case BROTLI_STATE_BEFORE_COMPRESSED_METABLOCK_HEADER: {
++ BrotliMetablockHeaderArena* h = &s->arena.header;
+ s->loop_counter = 0;
++ /* Initialize compressed metablock header arena. */
++ h->sub_loop_counter = 0;
++ /* Make small negative indexes addressable. */
++ h->symbol_lists =
++ &h->symbols_lists_array[BROTLI_HUFFMAN_MAX_CODE_LENGTH + 1];
++ h->substate_huffman = BROTLI_STATE_HUFFMAN_NONE;
++ h->substate_tree_group = BROTLI_STATE_TREE_GROUP_NONE;
++ h->substate_context_map = BROTLI_STATE_CONTEXT_MAP_NONE;
+ s->state = BROTLI_STATE_HUFFMAN_CODE_0;
+- break;
+-
+- case BROTLI_STATE_UNCOMPRESSED: {
+- result = CopyUncompressedBlockToOutput(
+- available_out, next_out, total_out, s);
+- if (result != BROTLI_DECODER_SUCCESS) {
+- break;
+- }
+- s->state = BROTLI_STATE_METABLOCK_DONE;
+- break;
+ }
+-
+- case BROTLI_STATE_METADATA:
+- for (; s->meta_block_remaining_len > 0; --s->meta_block_remaining_len) {
+- uint32_t bits;
+- /* Read one byte and ignore it. */
+- if (!BrotliSafeReadBits(br, 8, &bits)) {
+- result = BROTLI_DECODER_NEEDS_MORE_INPUT;
+- break;
+- }
+- }
+- if (result == BROTLI_DECODER_SUCCESS) {
+- s->state = BROTLI_STATE_METABLOCK_DONE;
+- }
+- break;
++ /* Fall through. */
+
+ case BROTLI_STATE_HUFFMAN_CODE_0:
+ if (s->loop_counter >= 3) {
+@@ -2238,6 +2319,30 @@ BrotliDecoderResult BrotliDecoderDecompressStream(
+ break;
+ }
+
++ case BROTLI_STATE_UNCOMPRESSED: {
++ result = CopyUncompressedBlockToOutput(
++ available_out, next_out, total_out, s);
++ if (result != BROTLI_DECODER_SUCCESS) {
++ break;
++ }
++ s->state = BROTLI_STATE_METABLOCK_DONE;
++ break;
++ }
++
++ case BROTLI_STATE_METADATA:
++ for (; s->meta_block_remaining_len > 0; --s->meta_block_remaining_len) {
++ uint32_t bits;
++ /* Read one byte and ignore it. */
++ if (!BrotliSafeReadBits(br, 8, &bits)) {
++ result = BROTLI_DECODER_NEEDS_MORE_INPUT;
++ break;
++ }
++ }
++ if (result == BROTLI_DECODER_SUCCESS) {
++ s->state = BROTLI_STATE_METABLOCK_DONE;
++ }
++ break;
++
+ case BROTLI_STATE_METABLOCK_HEADER_2: {
+ uint32_t bits;
+ if (!BrotliSafeReadBits(br, 6, &bits)) {
+@@ -2246,11 +2351,9 @@ BrotliDecoderResult BrotliDecoderDecompressStream(
+ }
+ s->distance_postfix_bits = bits & BitMask(2);
+ bits >>= 2;
+- s->num_direct_distance_codes = BROTLI_NUM_DISTANCE_SHORT_CODES +
+- (bits << s->distance_postfix_bits);
++ s->num_direct_distance_codes = bits << s->distance_postfix_bits;
+ BROTLI_LOG_UINT(s->num_direct_distance_codes);
+ BROTLI_LOG_UINT(s->distance_postfix_bits);
+- s->distance_postfix_mask = (int)BitMask(s->distance_postfix_bits);
+ s->context_modes =
+ (uint8_t*)BROTLI_DECODER_ALLOC(s, (size_t)s->num_block_types[0]);
+ if (s->context_modes == 0) {
+@@ -2282,17 +2385,19 @@ BrotliDecoderResult BrotliDecoderDecompressStream(
+ /* Fall through. */
+
+ case BROTLI_STATE_CONTEXT_MAP_2: {
+- uint32_t num_direct_codes =
+- s->num_direct_distance_codes - BROTLI_NUM_DISTANCE_SHORT_CODES;
+- uint32_t num_distance_codes = BROTLI_DISTANCE_ALPHABET_SIZE(
+- s->distance_postfix_bits, num_direct_codes,
+- (s->large_window ? BROTLI_LARGE_MAX_DISTANCE_BITS :
+- BROTLI_MAX_DISTANCE_BITS));
+- uint32_t max_distance_symbol = (s->large_window ?
+- BrotliMaxDistanceSymbol(
+- num_direct_codes, s->distance_postfix_bits) :
+- num_distance_codes);
++ uint32_t npostfix = s->distance_postfix_bits;
++ uint32_t ndirect = s->num_direct_distance_codes;
++ uint32_t distance_alphabet_size_max = BROTLI_DISTANCE_ALPHABET_SIZE(
++ npostfix, ndirect, BROTLI_MAX_DISTANCE_BITS);
++ uint32_t distance_alphabet_size_limit = distance_alphabet_size_max;
+ BROTLI_BOOL allocation_success = BROTLI_TRUE;
++ if (s->large_window) {
++ BrotliDistanceCodeLimit limit = BrotliCalculateDistanceCodeLimit(
++ BROTLI_MAX_ALLOWED_DISTANCE, npostfix, ndirect);
++ distance_alphabet_size_max = BROTLI_DISTANCE_ALPHABET_SIZE(
++ npostfix, ndirect, BROTLI_LARGE_MAX_DISTANCE_BITS);
++ distance_alphabet_size_limit = limit.max_alphabet_size;
++ }
+ result = DecodeContextMap(
+ s->num_block_types[2] << BROTLI_DISTANCE_CONTEXT_BITS,
+ &s->num_dist_htrees, &s->dist_context_map, s);
+@@ -2306,8 +2411,8 @@ BrotliDecoderResult BrotliDecoderDecompressStream(
+ s, &s->insert_copy_hgroup, BROTLI_NUM_COMMAND_SYMBOLS,
+ BROTLI_NUM_COMMAND_SYMBOLS, s->num_block_types[1]);
+ allocation_success &= BrotliDecoderHuffmanTreeGroupInit(
+- s, &s->distance_hgroup, num_distance_codes,
+- max_distance_symbol, s->num_dist_htrees);
++ s, &s->distance_hgroup, distance_alphabet_size_max,
++ distance_alphabet_size_limit, s->num_dist_htrees);
+ if (!allocation_success) {
+ return SaveErrorCode(s,
+ BROTLI_FAILURE(BROTLI_DECODER_ERROR_ALLOC_TREE_GROUPS));
+@@ -2329,18 +2434,24 @@ BrotliDecoderResult BrotliDecoderDecompressStream(
+ result = HuffmanTreeGroupDecode(hgroup, s);
+ if (result != BROTLI_DECODER_SUCCESS) break;
+ s->loop_counter++;
+- if (s->loop_counter >= 3) {
+- PrepareLiteralDecoding(s);
+- s->dist_context_map_slice = s->dist_context_map;
+- s->htree_command = s->insert_copy_hgroup.htrees[0];
+- if (!BrotliEnsureRingBuffer(s)) {
+- result = BROTLI_FAILURE(BROTLI_DECODER_ERROR_ALLOC_RING_BUFFER_2);
+- break;
+- }
+- s->state = BROTLI_STATE_COMMAND_BEGIN;
++ if (s->loop_counter < 3) {
++ break;
+ }
+- break;
++ s->state = BROTLI_STATE_BEFORE_COMPRESSED_METABLOCK_BODY;
+ }
++ /* Fall through. */
++
++ case BROTLI_STATE_BEFORE_COMPRESSED_METABLOCK_BODY:
++ PrepareLiteralDecoding(s);
++ s->dist_context_map_slice = s->dist_context_map;
++ s->htree_command = s->insert_copy_hgroup.htrees[0];
++ if (!BrotliEnsureRingBuffer(s)) {
++ result = BROTLI_FAILURE(BROTLI_DECODER_ERROR_ALLOC_RING_BUFFER_2);
++ break;
++ }
++ CalculateDistanceLut(s);
++ s->state = BROTLI_STATE_COMMAND_BEGIN;
++ /* Fall through. */
+
+ case BROTLI_STATE_COMMAND_BEGIN:
+ /* Fall through. */
+diff --git a/c/dec/huffman.h b/c/dec/huffman.h
+index 521ec6e..a8fbc45 100644
+--- a/c/dec/huffman.h
++++ b/c/dec/huffman.h
+@@ -18,12 +18,6 @@ extern "C" {
+
+ #define BROTLI_HUFFMAN_MAX_CODE_LENGTH 15
+
+-/* Maximum possible Huffman table size for an alphabet size of (index * 32),
+- max code length 15 and root table bits 8. */
+-static const uint16_t kMaxHuffmanTableSize[] = {
+- 256, 402, 436, 468, 500, 534, 566, 598, 630, 662, 694, 726, 758, 790, 822,
+- 854, 886, 920, 952, 984, 1016, 1048, 1080, 1112, 1144, 1176, 1208, 1240, 1272,
+- 1304, 1336, 1368, 1400, 1432, 1464, 1496, 1528};
+ /* BROTLI_NUM_BLOCK_LEN_SYMBOLS == 26 */
+ #define BROTLI_HUFFMAN_MAX_SIZE_26 396
+ /* BROTLI_MAX_BLOCK_TYPE_SYMBOLS == 258 */
+@@ -33,11 +27,66 @@ static const uint16_t kMaxHuffmanTableSize[] = {
+
+ #define BROTLI_HUFFMAN_MAX_CODE_LENGTH_CODE_LENGTH 5
+
++#if ((defined(BROTLI_TARGET_ARMV7) || defined(BROTLI_TARGET_ARMV8_32)) && \
++ BROTLI_GNUC_HAS_ATTRIBUTE(aligned, 2, 7, 0))
++#define BROTLI_HUFFMAN_CODE_FAST_LOAD
++#endif
++
++#if !defined(BROTLI_HUFFMAN_CODE_FAST_LOAD)
++/* Do not create this struct directly - use the ConstructHuffmanCode
++ * constructor below! */
+ typedef struct {
+ uint8_t bits; /* number of bits used for this symbol */
+ uint16_t value; /* symbol value or table offset */
+ } HuffmanCode;
+
++static BROTLI_INLINE HuffmanCode ConstructHuffmanCode(const uint8_t bits,
++ const uint16_t value) {
++ HuffmanCode h;
++ h.bits = bits;
++ h.value = value;
++ return h;
++}
++
++/* Please use the following macros to optimize HuffmanCode accesses in hot
++ * paths.
++ *
++ * For example, assuming |table| contains a HuffmanCode pointer:
++ *
++ * BROTLI_HC_MARK_TABLE_FOR_FAST_LOAD(table);
++ * BROTLI_HC_ADJUST_TABLE_INDEX(table, index_into_table);
++ * *bits = BROTLI_HC_GET_BITS(table);
++ * *value = BROTLI_HC_GET_VALUE(table);
++ * BROTLI_HC_ADJUST_TABLE_INDEX(table, offset);
++ * *bits2 = BROTLI_HC_GET_BITS(table);
++ * *value2 = BROTLI_HC_GET_VALUE(table);
++ *
++ */
++
++#define BROTLI_HC_MARK_TABLE_FOR_FAST_LOAD(H)
++#define BROTLI_HC_ADJUST_TABLE_INDEX(H, V) H += (V)
++
++/* These must be given a HuffmanCode pointer! */
++#define BROTLI_HC_FAST_LOAD_BITS(H) (H->bits)
++#define BROTLI_HC_FAST_LOAD_VALUE(H) (H->value)
++
++#else /* BROTLI_HUFFMAN_CODE_FAST_LOAD */
++
++typedef BROTLI_ALIGNED(4) uint32_t HuffmanCode;
++
++static BROTLI_INLINE HuffmanCode ConstructHuffmanCode(const uint8_t bits,
++ const uint16_t value) {
++ return (HuffmanCode) ((value & 0xFFFF) << 16) | (bits & 0xFF);
++}
++
++#define BROTLI_HC_MARK_TABLE_FOR_FAST_LOAD(H) uint32_t __fastload_##H = (*H)
++#define BROTLI_HC_ADJUST_TABLE_INDEX(H, V) H += (V); __fastload_##H = (*H)
++
++/* These must be given a HuffmanCode pointer! */
++#define BROTLI_HC_FAST_LOAD_BITS(H) ((__fastload_##H) & 0xFF)
++#define BROTLI_HC_FAST_LOAD_VALUE(H) ((__fastload_##H) >> 16)
++#endif /* BROTLI_HUFFMAN_CODE_FAST_LOAD */
++
+ /* Builds Huffman lookup table assuming code lengths are in symbol order. */
+ BROTLI_INTERNAL void BrotliBuildCodeLengthsHuffmanTable(HuffmanCode* root_table,
+ const uint8_t* const code_lengths, uint16_t* count);
+@@ -45,7 +94,7 @@ BROTLI_INTERNAL void BrotliBuildCodeLengthsHuffmanTable(HuffmanCode* root_table,
+ /* Builds Huffman lookup table assuming code lengths are in symbol order.
+ Returns size of resulting table. */
+ BROTLI_INTERNAL uint32_t BrotliBuildHuffmanTable(HuffmanCode* root_table,
+- int root_bits, const uint16_t* const symbol_lists, uint16_t* count_arg);
++ int root_bits, const uint16_t* const symbol_lists, uint16_t* count);
+
+ /* Builds a simple Huffman table. The |num_symbols| parameter is to be
+ interpreted as follows: 0 means 1 symbol, 1 means 2 symbols,
+@@ -55,13 +104,13 @@ BROTLI_INTERNAL uint32_t BrotliBuildSimpleHuffmanTable(HuffmanCode* table,
+ int root_bits, uint16_t* symbols, uint32_t num_symbols);
+
+ /* Contains a collection of Huffman trees with the same alphabet size. */
+-/* max_symbol is needed due to simple codes since log2(alphabet_size) could be
+- greater than log2(max_symbol). */
++/* alphabet_size_limit is needed due to simple codes, since
++ log2(alphabet_size_max) could be greater than log2(alphabet_size_limit). */
+ typedef struct {
+ HuffmanCode** htrees;
+ HuffmanCode* codes;
+- uint16_t alphabet_size;
+- uint16_t max_symbol;
++ uint16_t alphabet_size_max;
++ uint16_t alphabet_size_limit;
+ uint16_t num_htrees;
+ } HuffmanTreeGroup;
+
+diff --git a/c/dec/prefix.h b/c/dec/prefix.h
+index 3ea062d..481a2c7 100644
+--- a/c/dec/prefix.h
++++ b/c/dec/prefix.h
+@@ -13,24 +13,6 @@
+ #include "../common/constants.h"
+ #include <brotli/types.h>
+
+-/* Represents the range of values belonging to a prefix code:
+- [offset, offset + 2^nbits) */
+-struct PrefixCodeRange {
+- uint16_t offset;
+- uint8_t nbits;
+-};
+-
+-static const struct PrefixCodeRange
+- kBlockLengthPrefixCode[BROTLI_NUM_BLOCK_LEN_SYMBOLS] = {
+- { 1, 2}, { 5, 2}, { 9, 2}, { 13, 2},
+- { 17, 3}, { 25, 3}, { 33, 3}, { 41, 3},
+- { 49, 4}, { 65, 4}, { 81, 4}, { 97, 4},
+- { 113, 5}, { 145, 5}, { 177, 5}, { 209, 5},
+- { 241, 6}, { 305, 6}, { 369, 7}, { 497, 8},
+- { 753, 9}, { 1265, 10}, {2289, 11}, {4337, 12},
+- {8433, 13}, {16625, 24}
+-};
+-
+ typedef struct CmdLutElement {
+ uint8_t insert_len_extra_bits;
+ uint8_t copy_len_extra_bits;
+diff --git a/c/dec/state.c b/c/dec/state.c
+index e0b37c2..f847836 100644
+--- a/c/dec/state.c
++++ b/c/dec/state.c
+@@ -33,10 +33,7 @@ BROTLI_BOOL BrotliDecoderStateInit(BrotliDecoderState* s,
+ s->state = BROTLI_STATE_UNINITED;
+ s->large_window = 0;
+ s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_NONE;
+- s->substate_tree_group = BROTLI_STATE_TREE_GROUP_NONE;
+- s->substate_context_map = BROTLI_STATE_CONTEXT_MAP_NONE;
+ s->substate_uncompressed = BROTLI_STATE_UNCOMPRESSED_NONE;
+- s->substate_huffman = BROTLI_STATE_HUFFMAN_NONE;
+ s->substate_decode_uint8 = BROTLI_STATE_DECODE_UINT8_NONE;
+ s->substate_read_block_length = BROTLI_STATE_READ_BLOCK_LENGTH_NONE;
+
+@@ -59,8 +56,6 @@ BROTLI_BOOL BrotliDecoderStateInit(BrotliDecoderState* s,
+ s->context_map_slice = NULL;
+ s->dist_context_map_slice = NULL;
+
+- s->sub_loop_counter = 0;
+-
+ s->literal_hgroup.codes = NULL;
+ s->literal_hgroup.htrees = NULL;
+ s->insert_copy_hgroup.codes = NULL;
+@@ -84,9 +79,6 @@ BROTLI_BOOL BrotliDecoderStateInit(BrotliDecoderState* s,
+ s->block_type_trees = NULL;
+ s->block_len_trees = NULL;
+
+- /* Make small negative indexes addressable. */
+- s->symbol_lists = &s->symbols_lists_array[BROTLI_HUFFMAN_MAX_CODE_LENGTH + 1];
+-
+ s->mtf_upper_bound = 63;
+
+ s->dictionary = BrotliGetDictionary();
+@@ -142,17 +134,20 @@ void BrotliDecoderStateCleanup(BrotliDecoderState* s) {
+ }
+
+ BROTLI_BOOL BrotliDecoderHuffmanTreeGroupInit(BrotliDecoderState* s,
+- HuffmanTreeGroup* group, uint32_t alphabet_size, uint32_t max_symbol,
+- uint32_t ntrees) {
+- /* Pack two allocations into one */
+- const size_t max_table_size = kMaxHuffmanTableSize[(alphabet_size + 31) >> 5];
++ HuffmanTreeGroup* group, uint32_t alphabet_size_max,
++ uint32_t alphabet_size_limit, uint32_t ntrees) {
++ /* 376 = 256 (1-st level table) + 4 + 7 + 15 + 31 + 63 (2-nd level mix-tables)
++ This number is discovered "unlimited" "enough" calculator; it is actually
++ a wee bigger than required in several cases (especially for alphabets with
++ less than 16 symbols). */
++ const size_t max_table_size = alphabet_size_limit + 376;
+ const size_t code_size = sizeof(HuffmanCode) * ntrees * max_table_size;
+ const size_t htree_size = sizeof(HuffmanCode*) * ntrees;
+ /* Pointer alignment is, hopefully, wider than sizeof(HuffmanCode). */
+ HuffmanCode** p = (HuffmanCode**)BROTLI_DECODER_ALLOC(s,
+ code_size + htree_size);
+- group->alphabet_size = (uint16_t)alphabet_size;
+- group->max_symbol = (uint16_t)max_symbol;
++ group->alphabet_size_max = (uint16_t)alphabet_size_max;
++ group->alphabet_size_limit = (uint16_t)alphabet_size_limit;
+ group->num_htrees = (uint16_t)ntrees;
+ group->htrees = p;
+ group->codes = (HuffmanCode*)(&p[ntrees]);
+diff --git a/c/dec/state.h b/c/dec/state.h
+index d28b639..54dab69 100644
+--- a/c/dec/state.h
++++ b/c/dec/state.h
+@@ -21,6 +21,95 @@
+ extern "C" {
+ #endif
+
++/* Graphviz diagram that describes state transitions:
++
++digraph States {
++ graph [compound=true]
++ concentrate=true
++ node [shape="box"]
++
++ UNINITED -> {LARGE_WINDOW_BITS -> INITIALIZE}
++ subgraph cluster_metablock_workflow {
++ style="rounded"
++ label=< <B>METABLOCK CYCLE</B> >
++ METABLOCK_BEGIN -> METABLOCK_HEADER
++ METABLOCK_HEADER:sw -> METADATA
++ METABLOCK_HEADER:s -> UNCOMPRESSED
++ METABLOCK_HEADER:se -> METABLOCK_DONE:ne
++ METADATA:s -> METABLOCK_DONE:w
++ UNCOMPRESSED:s -> METABLOCK_DONE:n
++ METABLOCK_DONE:e -> METABLOCK_BEGIN:e [constraint="false"]
++ }
++ INITIALIZE -> METABLOCK_BEGIN
++ METABLOCK_DONE -> DONE
++
++ subgraph cluster_compressed_metablock {
++ style="rounded"
++ label=< <B>COMPRESSED METABLOCK</B> >
++
++ subgraph cluster_command {
++ style="rounded"
++ label=< <B>HOT LOOP</B> >
++
++ _METABLOCK_DONE_PORT_ [shape=point style=invis]
++
++ {
++ // Set different shape for nodes returning from "compressed metablock".
++ node [shape=invhouse]; CMD_INNER CMD_POST_DECODE_LITERALS;
++ CMD_POST_WRAP_COPY; CMD_INNER_WRITE; CMD_POST_WRITE_1;
++ }
++
++ CMD_BEGIN -> CMD_INNER -> CMD_POST_DECODE_LITERALS -> CMD_POST_WRAP_COPY
++
++ // IO ("write") nodes are not in the hot loop!
++ CMD_INNER_WRITE [style=dashed]
++ CMD_INNER -> CMD_INNER_WRITE
++ CMD_POST_WRITE_1 [style=dashed]
++ CMD_POST_DECODE_LITERALS -> CMD_POST_WRITE_1
++ CMD_POST_WRITE_2 [style=dashed]
++ CMD_POST_WRAP_COPY -> CMD_POST_WRITE_2
++
++ CMD_POST_WRITE_1 -> CMD_BEGIN:s [constraint="false"]
++ CMD_INNER_WRITE -> {CMD_INNER CMD_POST_DECODE_LITERALS}
++ [constraint="false"]
++ CMD_BEGIN:ne -> CMD_POST_DECODE_LITERALS [constraint="false"]
++ CMD_POST_WRAP_COPY -> CMD_BEGIN [constraint="false"]
++ CMD_POST_DECODE_LITERALS -> CMD_BEGIN:ne [constraint="false"]
++ CMD_POST_WRITE_2 -> CMD_POST_WRAP_COPY [constraint="false"]
++ {rank=same; CMD_BEGIN; CMD_INNER; CMD_POST_DECODE_LITERALS;
++ CMD_POST_WRAP_COPY}
++ {rank=same; CMD_INNER_WRITE; CMD_POST_WRITE_1; CMD_POST_WRITE_2}
++
++ {CMD_INNER CMD_POST_DECODE_LITERALS CMD_POST_WRAP_COPY} ->
++ _METABLOCK_DONE_PORT_ [style=invis]
++ {CMD_INNER_WRITE CMD_POST_WRITE_1} -> _METABLOCK_DONE_PORT_
++ [constraint="false" style=invis]
++ }
++
++ BEFORE_COMPRESSED_METABLOCK_HEADER:s -> HUFFMAN_CODE_0:n
++ HUFFMAN_CODE_0 -> HUFFMAN_CODE_1 -> HUFFMAN_CODE_2 -> HUFFMAN_CODE_3
++ HUFFMAN_CODE_0 -> METABLOCK_HEADER_2 -> CONTEXT_MODES -> CONTEXT_MAP_1
++ CONTEXT_MAP_1 -> CONTEXT_MAP_2 -> TREE_GROUP
++ TREE_GROUP -> BEFORE_COMPRESSED_METABLOCK_BODY:e
++ BEFORE_COMPRESSED_METABLOCK_BODY:s -> CMD_BEGIN:n
++
++ HUFFMAN_CODE_3:e -> HUFFMAN_CODE_0:ne [constraint="false"]
++ {rank=same; HUFFMAN_CODE_0; HUFFMAN_CODE_1; HUFFMAN_CODE_2; HUFFMAN_CODE_3}
++ {rank=same; METABLOCK_HEADER_2; CONTEXT_MODES; CONTEXT_MAP_1; CONTEXT_MAP_2;
++ TREE_GROUP}
++ }
++ METABLOCK_HEADER:e -> BEFORE_COMPRESSED_METABLOCK_HEADER:n
++
++ _METABLOCK_DONE_PORT_ -> METABLOCK_DONE:se
++ [constraint="false" ltail=cluster_command]
++
++ UNINITED [shape=Mdiamond];
++ DONE [shape=Msquare];
++}
++
++
++ */
++
+ typedef enum {
+ BROTLI_STATE_UNINITED,
+ BROTLI_STATE_LARGE_WINDOW_BITS,
+@@ -39,6 +128,7 @@ typedef enum {
+ BROTLI_STATE_METABLOCK_DONE,
+ BROTLI_STATE_COMMAND_POST_WRITE_1,
+ BROTLI_STATE_COMMAND_POST_WRITE_2,
++ BROTLI_STATE_BEFORE_COMPRESSED_METABLOCK_HEADER,
+ BROTLI_STATE_HUFFMAN_CODE_0,
+ BROTLI_STATE_HUFFMAN_CODE_1,
+ BROTLI_STATE_HUFFMAN_CODE_2,
+@@ -46,6 +136,7 @@ typedef enum {
+ BROTLI_STATE_CONTEXT_MAP_1,
+ BROTLI_STATE_CONTEXT_MAP_2,
+ BROTLI_STATE_TREE_GROUP,
++ BROTLI_STATE_BEFORE_COMPRESSED_METABLOCK_BODY,
+ BROTLI_STATE_DONE
+ } BrotliRunningState;
+
+@@ -98,6 +189,50 @@ typedef enum {
+ BROTLI_STATE_READ_BLOCK_LENGTH_SUFFIX
+ } BrotliRunningReadBlockLengthState;
+
++typedef struct BrotliMetablockHeaderArena {
++ BrotliRunningTreeGroupState substate_tree_group;
++ BrotliRunningContextMapState substate_context_map;
++ BrotliRunningHuffmanState substate_huffman;
++
++ uint32_t sub_loop_counter;
++
++ uint32_t repeat_code_len;
++ uint32_t prev_code_len;
++
++ /* For ReadHuffmanCode. */
++ uint32_t symbol;
++ uint32_t repeat;
++ uint32_t space;
++
++ /* Huffman table for "histograms". */
++ HuffmanCode table[32];
++ /* List of heads of symbol chains. */
++ uint16_t* symbol_lists;
++ /* Storage from symbol_lists. */
++ uint16_t symbols_lists_array[BROTLI_HUFFMAN_MAX_CODE_LENGTH + 1 +
++ BROTLI_NUM_COMMAND_SYMBOLS];
++ /* Tails of symbol chains. */
++ int next_symbol[32];
++ uint8_t code_length_code_lengths[BROTLI_CODE_LENGTH_CODES];
++ /* Population counts for the code lengths. */
++ uint16_t code_length_histo[16];
++
++ /* For HuffmanTreeGroupDecode. */
++ int htree_index;
++ HuffmanCode* next;
++
++ /* For DecodeContextMap. */
++ uint32_t context_index;
++ uint32_t max_run_length_prefix;
++ uint32_t code;
++ HuffmanCode context_map_table[BROTLI_HUFFMAN_MAX_SIZE_272];
++} BrotliMetablockHeaderArena;
++
++typedef struct BrotliMetablockBodyArena {
++ uint8_t dist_extra_bits[544];
++ uint32_t dist_offset[544];
++} BrotliMetablockBodyArena;
++
+ struct BrotliDecoderStateStruct {
+ BrotliRunningState state;
+
+@@ -110,7 +245,8 @@ struct BrotliDecoderStateStruct {
+ brotli_free_func free_func;
+ void* memory_manager_opaque;
+
+- /* Temporary storage for remaining input. */
++ /* Temporary storage for remaining input. Brotli stream format is designed in
++ a way, that 64 bits are enough to make progress in decoding. */
+ union {
+ uint64_t u64;
+ uint8_t u8[8];
+@@ -125,7 +261,6 @@ struct BrotliDecoderStateStruct {
+ int dist_rb_idx;
+ int dist_rb[4];
+ int error_code;
+- uint32_t sub_loop_counter;
+ uint8_t* ringbuffer;
+ uint8_t* ringbuffer_end;
+ HuffmanCode* htree_command;
+@@ -153,13 +288,10 @@ struct BrotliDecoderStateStruct {
+ uint32_t block_type_rb[6];
+ uint32_t distance_postfix_bits;
+ uint32_t num_direct_distance_codes;
+- int distance_postfix_mask;
+ uint32_t num_dist_htrees;
+ uint8_t* dist_context_map;
+ HuffmanCode* literal_htree;
+ uint8_t dist_htree_index;
+- uint32_t repeat_code_len;
+- uint32_t prev_code_len;
+
+ int copy_length;
+ int distance_code;
+@@ -168,33 +300,6 @@ struct BrotliDecoderStateStruct {
+ size_t rb_roundtrips; /* how many times we went around the ring-buffer */
+ size_t partial_pos_out; /* how much output to the user in total */
+
+- /* For ReadHuffmanCode. */
+- uint32_t symbol;
+- uint32_t repeat;
+- uint32_t space;
+-
+- HuffmanCode table[32];
+- /* List of heads of symbol chains. */
+- uint16_t* symbol_lists;
+- /* Storage from symbol_lists. */
+- uint16_t symbols_lists_array[BROTLI_HUFFMAN_MAX_CODE_LENGTH + 1 +
+- BROTLI_NUM_COMMAND_SYMBOLS];
+- /* Tails of symbol chains. */
+- int next_symbol[32];
+- uint8_t code_length_code_lengths[BROTLI_CODE_LENGTH_CODES];
+- /* Population counts for the code lengths. */
+- uint16_t code_length_histo[16];
+-
+- /* For HuffmanTreeGroupDecode. */
+- int htree_index;
+- HuffmanCode* next;
+-
+- /* For DecodeContextMap. */
+- uint32_t context_index;
+- uint32_t max_run_length_prefix;
+- uint32_t code;
+- HuffmanCode context_map_table[BROTLI_HUFFMAN_MAX_SIZE_272];
+-
+ /* For InverseMoveToFrontTransform. */
+ uint32_t mtf_upper_bound;
+ uint32_t mtf[64 + 1];
+@@ -203,10 +308,7 @@ struct BrotliDecoderStateStruct {
+
+ /* States inside function calls. */
+ BrotliRunningMetablockHeaderState substate_metablock_header;
+- BrotliRunningTreeGroupState substate_tree_group;
+- BrotliRunningContextMapState substate_context_map;
+ BrotliRunningUncompressedState substate_uncompressed;
+- BrotliRunningHuffmanState substate_huffman;
+ BrotliRunningDecodeUint8State substate_decode_uint8;
+ BrotliRunningReadBlockLengthState substate_read_block_length;
+
+@@ -229,6 +331,11 @@ struct BrotliDecoderStateStruct {
+ const BrotliTransforms* transforms;
+
+ uint32_t trivial_literal_contexts[8]; /* 256 bits */
++
++ union {
++ BrotliMetablockHeaderArena header;
++ BrotliMetablockBodyArena body;
++ } arena;
+ };
+
+ typedef struct BrotliDecoderStateStruct BrotliDecoderStateInternal;
+@@ -241,8 +348,8 @@ BROTLI_INTERNAL void BrotliDecoderStateMetablockBegin(BrotliDecoderState* s);
+ BROTLI_INTERNAL void BrotliDecoderStateCleanupAfterMetablock(
+ BrotliDecoderState* s);
+ BROTLI_INTERNAL BROTLI_BOOL BrotliDecoderHuffmanTreeGroupInit(
+- BrotliDecoderState* s, HuffmanTreeGroup* group, uint32_t alphabet_size,
+- uint32_t max_symbol, uint32_t ntrees);
++ BrotliDecoderState* s, HuffmanTreeGroup* group, uint32_t alphabet_size_max,
++ uint32_t alphabet_size_limit, uint32_t ntrees);
+
+ #define BROTLI_DECODER_ALLOC(S, L) S->alloc_func(S->memory_manager_opaque, L)
+
+diff --git a/c/enc/brotli_bit_stream.c b/c/enc/brotli_bit_stream.c
+index aaf2dad..8e68059 100644
+--- a/c/enc/brotli_bit_stream.c
++++ b/c/enc/brotli_bit_stream.c
+@@ -34,33 +34,18 @@ extern "C" {
+ BROTLI_DISTANCE_ALPHABET_SIZE(0, 0, BROTLI_LARGE_MAX_DISTANCE_BITS)
+ /* MAX_SIMPLE_DISTANCE_ALPHABET_SIZE == 140 */
+
+-/* Represents the range of values belonging to a prefix code:
+- [offset, offset + 2^nbits) */
+-typedef struct PrefixCodeRange {
+- uint32_t offset;
+- uint32_t nbits;
+-} PrefixCodeRange;
+-
+-static const PrefixCodeRange
+- kBlockLengthPrefixCode[BROTLI_NUM_BLOCK_LEN_SYMBOLS] = {
+- { 1, 2}, { 5, 2}, { 9, 2}, {13, 2}, {17, 3}, { 25, 3}, { 33, 3},
+- {41, 3}, {49, 4}, {65, 4}, {81, 4}, {97, 4}, {113, 5}, {145, 5},
+- {177, 5}, { 209, 5}, { 241, 6}, { 305, 6}, { 369, 7}, { 497, 8},
+- {753, 9}, {1265, 10}, {2289, 11}, {4337, 12}, {8433, 13}, {16625, 24}
+-};
+-
+ static BROTLI_INLINE uint32_t BlockLengthPrefixCode(uint32_t len) {
+ uint32_t code = (len >= 177) ? (len >= 753 ? 20 : 14) : (len >= 41 ? 7 : 0);
+ while (code < (BROTLI_NUM_BLOCK_LEN_SYMBOLS - 1) &&
+- len >= kBlockLengthPrefixCode[code + 1].offset) ++code;
++ len >= _kBrotliPrefixCodeRanges[code + 1].offset) ++code;
+ return code;
+ }
+
+ static BROTLI_INLINE void GetBlockLengthPrefixCode(uint32_t len, size_t* code,
+ uint32_t* n_extra, uint32_t* extra) {
+ *code = BlockLengthPrefixCode(len);
+- *n_extra = kBlockLengthPrefixCode[*code].nbits;
+- *extra = len - kBlockLengthPrefixCode[*code].offset;
++ *n_extra = _kBrotliPrefixCodeRanges[*code].nbits;
++ *extra = len - _kBrotliPrefixCodeRanges[*code].offset;
+ }
+
+ typedef struct BlockTypeCodeCalculator {
+diff --git a/research/brotli_decoder.c b/research/brotli_decoder.c
+index b1d556d..4b0bc4a 100644
+--- a/research/brotli_decoder.c
++++ b/research/brotli_decoder.c
+@@ -38,6 +38,7 @@ void cleanup(Context* ctx) {
+
+ void fail(Context* ctx, const char* message) {
+ fprintf(stderr, "%s\n", message);
++ cleanup(ctx);
+ exit(1);
+ }
+
+diff --git a/scripts/sources.lst b/scripts/sources.lst
+index 5e8e817..cd0b343 100644
+--- a/scripts/sources.lst
++++ b/scripts/sources.lst
+@@ -5,6 +5,7 @@ BROTLI_CLI_C = \
+ c/tools/brotli.c
+
+ BROTLI_COMMON_C = \
++ c/common/constants.c \
+ c/common/dictionary.c \
+ c/common/transform.c
+
+diff --git a/setup.py b/setup.py
+index 1491db3..7bd6314 100644
+--- a/setup.py
++++ b/setup.py
+@@ -181,6 +181,7 @@ EXT_MODULES = [
+ '_brotli',
+ sources=[
+ 'python/_brotli.cc',
++ 'c/common/constants.c',
+ 'c/common/dictionary.c',
+ 'c/common/transform.c',
+ 'c/dec/bit_reader.c',
+--
+2.25.4
+
diff --git a/SPECS/brotli.spec b/SPECS/brotli.spec
index d86929c..e201b9c 100644
--- a/SPECS/brotli.spec
+++ b/SPECS/brotli.spec
@@ -7,13 +7,15 @@
Name: brotli
Version: 1.0.6
-Release: 2%{?dist}
+Release: 3%{?dist}
Summary: Lossless compression algorithm
License: MIT
URL: https://github.com/google/brotli
Source0: https://github.com/google/brotli/archive/v%{version}.tar.gz
+Patch1: rhbz1881156.patch
+
%if %{with python2}
BuildRequires: python2-devel
%endif
@@ -69,13 +71,14 @@ It is similar in speed with deflate but offers more dense compression.
This package installs the development files
%prep
-%autosetup
+%autosetup -p1 -S git
# fix permissions for -debuginfo
# rpmlint will complain if I create an extra %%files section for
# -debuginfo for this so we'll put it here instead
%{__chmod} 644 c/enc/*.[ch]
%{__chmod} 644 c/include/brotli/*.h
%{__chmod} 644 c/tools/brotli.c
+
%build
mkdir -p build
@@ -148,6 +151,9 @@ cd ..
%changelog
+* Thu Oct 01 2020 Eike Rathke <erack@redhat.com> - 1.0.6-3
+- Resolves: CVE-2020-8927
+
* Wed Jun 17 2020 Eike Rathke <erack@redhat.com> - 1.0.6-2
- Resolves: rhbz#1737412 bump NRV for build to compose