diff options
Diffstat (limited to 'BaseTools/Source/C/BrotliCompress/enc/brotli_bit_stream.c')
-rw-r--r-- | BaseTools/Source/C/BrotliCompress/enc/brotli_bit_stream.c | 1334 |
1 files changed, 0 insertions, 1334 deletions
diff --git a/BaseTools/Source/C/BrotliCompress/enc/brotli_bit_stream.c b/BaseTools/Source/C/BrotliCompress/enc/brotli_bit_stream.c deleted file mode 100644 index f77a2a61f0..0000000000 --- a/BaseTools/Source/C/BrotliCompress/enc/brotli_bit_stream.c +++ /dev/null @@ -1,1334 +0,0 @@ -/* Copyright 2014 Google Inc. All Rights Reserved.
-
- Distributed under MIT license.
- See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
-*/
-
-/* Brotli bit stream functions to support the low level format. There are no
- compression algorithms here, just the right ordering of bits to match the
- specs. */
-
-#include "./brotli_bit_stream.h"
-
-#include <string.h> /* memcpy, memset */
-
-#include "../common/constants.h"
-#include "../common/types.h"
-#include "./context.h"
-#include "./entropy_encode.h"
-#include "./entropy_encode_static.h"
-#include "./fast_log.h"
-#include "./memory.h"
-#include "./port.h"
-#include "./write_bits.h"
-
-#if defined(__cplusplus) || defined(c_plusplus)
-extern "C" {
-#endif
-
-#define MAX_HUFFMAN_TREE_SIZE (2 * BROTLI_NUM_COMMAND_SYMBOLS + 1)
-
-/* 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;
- 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;
-}
-
-typedef struct BlockTypeCodeCalculator {
- size_t last_type;
- size_t second_last_type;
-} BlockTypeCodeCalculator;
-
-static void InitBlockTypeCodeCalculator(BlockTypeCodeCalculator* self) {
- self->last_type = 1;
- self->second_last_type = 0;
-}
-
-static BROTLI_INLINE size_t NextBlockTypeCode(
- BlockTypeCodeCalculator* calculator, uint8_t type) {
- size_t type_code = (type == calculator->last_type + 1) ? 1u :
- (type == calculator->second_last_type) ? 0u : type + 2u;
- calculator->second_last_type = calculator->last_type;
- calculator->last_type = type;
- return type_code;
-}
-
-/* nibblesbits represents the 2 bits to encode MNIBBLES (0-3)
- REQUIRES: length > 0
- REQUIRES: length <= (1 << 24) */
-static void BrotliEncodeMlen(size_t length, uint64_t* bits,
- size_t* numbits, uint64_t* nibblesbits) {
- size_t lg = (length == 1) ? 1 : Log2FloorNonZero((uint32_t)(length - 1)) + 1;
- size_t mnibbles = (lg < 16 ? 16 : (lg + 3)) / 4;
- assert(length > 0);
- assert(length <= (1 << 24));
- assert(lg <= 24);
- *nibblesbits = mnibbles - 4;
- *numbits = mnibbles * 4;
- *bits = length - 1;
-}
-
-static BROTLI_INLINE void StoreCommandExtra(
- const Command* cmd, size_t* storage_ix, uint8_t* storage) {
- uint32_t copylen_code = CommandCopyLenCode(cmd);
- uint16_t inscode = GetInsertLengthCode(cmd->insert_len_);
- uint16_t copycode = GetCopyLengthCode(copylen_code);
- uint32_t insnumextra = GetInsertExtra(inscode);
- uint64_t insextraval = cmd->insert_len_ - GetInsertBase(inscode);
- uint64_t copyextraval = copylen_code - GetCopyBase(copycode);
- uint64_t bits = (copyextraval << insnumextra) | insextraval;
- BrotliWriteBits(
- insnumextra + GetCopyExtra(copycode), bits, storage_ix, storage);
-}
-
-/* Data structure that stores almost everything that is needed to encode each
- block switch command. */
-typedef struct BlockSplitCode {
- BlockTypeCodeCalculator type_code_calculator;
- uint8_t type_depths[BROTLI_MAX_BLOCK_TYPE_SYMBOLS];
- uint16_t type_bits[BROTLI_MAX_BLOCK_TYPE_SYMBOLS];
- uint8_t length_depths[BROTLI_NUM_BLOCK_LEN_SYMBOLS];
- uint16_t length_bits[BROTLI_NUM_BLOCK_LEN_SYMBOLS];
-} BlockSplitCode;
-
-/* Stores a number between 0 and 255. */
-static void StoreVarLenUint8(size_t n, size_t* storage_ix, uint8_t* storage) {
- if (n == 0) {
- BrotliWriteBits(1, 0, storage_ix, storage);
- } else {
- size_t nbits = Log2FloorNonZero(n);
- BrotliWriteBits(1, 1, storage_ix, storage);
- BrotliWriteBits(3, nbits, storage_ix, storage);
- BrotliWriteBits(nbits, n - ((size_t)1 << nbits), storage_ix, storage);
- }
-}
-
-/* Stores the compressed meta-block header.
- REQUIRES: length > 0
- REQUIRES: length <= (1 << 24) */
-static void StoreCompressedMetaBlockHeader(BROTLI_BOOL is_final_block,
- size_t length,
- size_t* storage_ix,
- uint8_t* storage) {
- uint64_t lenbits;
- size_t nlenbits;
- uint64_t nibblesbits;
-
- /* Write ISLAST bit. */
- BrotliWriteBits(1, (uint64_t)is_final_block, storage_ix, storage);
- /* Write ISEMPTY bit. */
- if (is_final_block) {
- BrotliWriteBits(1, 0, storage_ix, storage);
- }
-
- BrotliEncodeMlen(length, &lenbits, &nlenbits, &nibblesbits);
- BrotliWriteBits(2, nibblesbits, storage_ix, storage);
- BrotliWriteBits(nlenbits, lenbits, storage_ix, storage);
-
- if (!is_final_block) {
- /* Write ISUNCOMPRESSED bit. */
- BrotliWriteBits(1, 0, storage_ix, storage);
- }
-}
-
-/* Stores the uncompressed meta-block header.
- REQUIRES: length > 0
- REQUIRES: length <= (1 << 24) */
-static void BrotliStoreUncompressedMetaBlockHeader(size_t length,
- size_t* storage_ix,
- uint8_t* storage) {
- uint64_t lenbits;
- size_t nlenbits;
- uint64_t nibblesbits;
-
- /* Write ISLAST bit.
- Uncompressed block cannot be the last one, so set to 0. */
- BrotliWriteBits(1, 0, storage_ix, storage);
- BrotliEncodeMlen(length, &lenbits, &nlenbits, &nibblesbits);
- BrotliWriteBits(2, nibblesbits, storage_ix, storage);
- BrotliWriteBits(nlenbits, lenbits, storage_ix, storage);
- /* Write ISUNCOMPRESSED bit. */
- BrotliWriteBits(1, 1, storage_ix, storage);
-}
-
-static void BrotliStoreHuffmanTreeOfHuffmanTreeToBitMask(
- const int num_codes, const uint8_t* code_length_bitdepth,
- size_t* storage_ix, uint8_t* storage) {
- static const uint8_t kStorageOrder[BROTLI_CODE_LENGTH_CODES] = {
- 1, 2, 3, 4, 0, 5, 17, 6, 16, 7, 8, 9, 10, 11, 12, 13, 14, 15
- };
- /* The bit lengths of the Huffman code over the code length alphabet
- are compressed with the following static Huffman code:
- Symbol Code
- ------ ----
- 0 00
- 1 1110
- 2 110
- 3 01
- 4 10
- 5 1111 */
- static const uint8_t kHuffmanBitLengthHuffmanCodeSymbols[6] = {
- 0, 7, 3, 2, 1, 15
- };
- static const uint8_t kHuffmanBitLengthHuffmanCodeBitLengths[6] = {
- 2, 4, 3, 2, 2, 4
- };
-
- size_t skip_some = 0; /* skips none. */
-
- /* Throw away trailing zeros: */
- size_t codes_to_store = BROTLI_CODE_LENGTH_CODES;
- if (num_codes > 1) {
- for (; codes_to_store > 0; --codes_to_store) {
- if (code_length_bitdepth[kStorageOrder[codes_to_store - 1]] != 0) {
- break;
- }
- }
- }
- if (code_length_bitdepth[kStorageOrder[0]] == 0 &&
- code_length_bitdepth[kStorageOrder[1]] == 0) {
- skip_some = 2; /* skips two. */
- if (code_length_bitdepth[kStorageOrder[2]] == 0) {
- skip_some = 3; /* skips three. */
- }
- }
- BrotliWriteBits(2, skip_some, storage_ix, storage);
- {
- size_t i;
- for (i = skip_some; i < codes_to_store; ++i) {
- size_t l = code_length_bitdepth[kStorageOrder[i]];
- BrotliWriteBits(kHuffmanBitLengthHuffmanCodeBitLengths[l],
- kHuffmanBitLengthHuffmanCodeSymbols[l], storage_ix, storage);
- }
- }
-}
-
-static void BrotliStoreHuffmanTreeToBitMask(
- const size_t huffman_tree_size, const uint8_t* huffman_tree,
- const uint8_t* huffman_tree_extra_bits, const uint8_t* code_length_bitdepth,
- const uint16_t* code_length_bitdepth_symbols,
- size_t* BROTLI_RESTRICT storage_ix, uint8_t* BROTLI_RESTRICT storage) {
- size_t i;
- for (i = 0; i < huffman_tree_size; ++i) {
- size_t ix = huffman_tree[i];
- BrotliWriteBits(code_length_bitdepth[ix], code_length_bitdepth_symbols[ix],
- storage_ix, storage);
- /* Extra bits */
- switch (ix) {
- case BROTLI_REPEAT_PREVIOUS_CODE_LENGTH:
- BrotliWriteBits(2, huffman_tree_extra_bits[i], storage_ix, storage);
- break;
- case BROTLI_REPEAT_ZERO_CODE_LENGTH:
- BrotliWriteBits(3, huffman_tree_extra_bits[i], storage_ix, storage);
- break;
- }
- }
-}
-
-static void StoreSimpleHuffmanTree(const uint8_t* depths,
- size_t symbols[4],
- size_t num_symbols,
- size_t max_bits,
- size_t *storage_ix, uint8_t *storage) {
- /* value of 1 indicates a simple Huffman code */
- BrotliWriteBits(2, 1, storage_ix, storage);
- BrotliWriteBits(2, num_symbols - 1, storage_ix, storage); /* NSYM - 1 */
-
- {
- /* Sort */
- size_t i;
- for (i = 0; i < num_symbols; i++) {
- size_t j;
- for (j = i + 1; j < num_symbols; j++) {
- if (depths[symbols[j]] < depths[symbols[i]]) {
- BROTLI_SWAP(size_t, symbols, j, i);
- }
- }
- }
- }
-
- if (num_symbols == 2) {
- BrotliWriteBits(max_bits, symbols[0], storage_ix, storage);
- BrotliWriteBits(max_bits, symbols[1], storage_ix, storage);
- } else if (num_symbols == 3) {
- BrotliWriteBits(max_bits, symbols[0], storage_ix, storage);
- BrotliWriteBits(max_bits, symbols[1], storage_ix, storage);
- BrotliWriteBits(max_bits, symbols[2], storage_ix, storage);
- } else {
- BrotliWriteBits(max_bits, symbols[0], storage_ix, storage);
- BrotliWriteBits(max_bits, symbols[1], storage_ix, storage);
- BrotliWriteBits(max_bits, symbols[2], storage_ix, storage);
- BrotliWriteBits(max_bits, symbols[3], storage_ix, storage);
- /* tree-select */
- BrotliWriteBits(1, depths[symbols[0]] == 1 ? 1 : 0, storage_ix, storage);
- }
-}
-
-/* num = alphabet size
- depths = symbol depths */
-void BrotliStoreHuffmanTree(const uint8_t* depths, size_t num,
- HuffmanTree* tree,
- size_t *storage_ix, uint8_t *storage) {
- /* Write the Huffman tree into the brotli-representation.
- The command alphabet is the largest, so this allocation will fit all
- alphabets. */
- uint8_t huffman_tree[BROTLI_NUM_COMMAND_SYMBOLS];
- uint8_t huffman_tree_extra_bits[BROTLI_NUM_COMMAND_SYMBOLS];
- size_t huffman_tree_size = 0;
- uint8_t code_length_bitdepth[BROTLI_CODE_LENGTH_CODES] = { 0 };
- uint16_t code_length_bitdepth_symbols[BROTLI_CODE_LENGTH_CODES];
- uint32_t huffman_tree_histogram[BROTLI_CODE_LENGTH_CODES] = { 0 };
- size_t i;
- int num_codes = 0;
- size_t code = 0;
-
- assert(num <= BROTLI_NUM_COMMAND_SYMBOLS);
-
- BrotliWriteHuffmanTree(depths, num, &huffman_tree_size, huffman_tree,
- huffman_tree_extra_bits);
-
- /* Calculate the statistics of the Huffman tree in brotli-representation. */
- for (i = 0; i < huffman_tree_size; ++i) {
- ++huffman_tree_histogram[huffman_tree[i]];
- }
-
- for (i = 0; i < BROTLI_CODE_LENGTH_CODES; ++i) {
- if (huffman_tree_histogram[i]) {
- if (num_codes == 0) {
- code = i;
- num_codes = 1;
- } else if (num_codes == 1) {
- num_codes = 2;
- break;
- }
- }
- }
-
- /* Calculate another Huffman tree to use for compressing both the
- earlier Huffman tree with. */
- BrotliCreateHuffmanTree(huffman_tree_histogram, BROTLI_CODE_LENGTH_CODES,
- 5, tree, code_length_bitdepth);
- BrotliConvertBitDepthsToSymbols(code_length_bitdepth,
- BROTLI_CODE_LENGTH_CODES,
- code_length_bitdepth_symbols);
-
- /* Now, we have all the data, let's start storing it */
- BrotliStoreHuffmanTreeOfHuffmanTreeToBitMask(num_codes, code_length_bitdepth,
- storage_ix, storage);
-
- if (num_codes == 1) {
- code_length_bitdepth[code] = 0;
- }
-
- /* Store the real huffman tree now. */
- BrotliStoreHuffmanTreeToBitMask(huffman_tree_size,
- huffman_tree,
- huffman_tree_extra_bits,
- code_length_bitdepth,
- code_length_bitdepth_symbols,
- storage_ix, storage);
-}
-
-/* Builds a Huffman tree from histogram[0:length] into depth[0:length] and
- bits[0:length] and stores the encoded tree to the bit stream. */
-static void BuildAndStoreHuffmanTree(const uint32_t *histogram,
- const size_t length,
- HuffmanTree* tree,
- uint8_t* depth,
- uint16_t* bits,
- size_t* storage_ix,
- uint8_t* storage) {
- size_t count = 0;
- size_t s4[4] = { 0 };
- size_t i;
- size_t max_bits = 0;
- for (i = 0; i < length; i++) {
- if (histogram[i]) {
- if (count < 4) {
- s4[count] = i;
- } else if (count > 4) {
- break;
- }
- count++;
- }
- }
-
- {
- size_t max_bits_counter = length - 1;
- while (max_bits_counter) {
- max_bits_counter >>= 1;
- ++max_bits;
- }
- }
-
- if (count <= 1) {
- BrotliWriteBits(4, 1, storage_ix, storage);
- BrotliWriteBits(max_bits, s4[0], storage_ix, storage);
- depth[s4[0]] = 0;
- bits[s4[0]] = 0;
- return;
- }
-
- memset(depth, 0, length * sizeof(depth[0]));
- BrotliCreateHuffmanTree(histogram, length, 15, tree, depth);
- BrotliConvertBitDepthsToSymbols(depth, length, bits);
-
- if (count <= 4) {
- StoreSimpleHuffmanTree(depth, s4, count, max_bits, storage_ix, storage);
- } else {
- BrotliStoreHuffmanTree(depth, length, tree, storage_ix, storage);
- }
-}
-
-static BROTLI_INLINE BROTLI_BOOL SortHuffmanTree(
- const HuffmanTree* v0, const HuffmanTree* v1) {
- return TO_BROTLI_BOOL(v0->total_count_ < v1->total_count_);
-}
-
-void BrotliBuildAndStoreHuffmanTreeFast(MemoryManager* m,
- const uint32_t* histogram,
- const size_t histogram_total,
- const size_t max_bits,
- uint8_t* depth, uint16_t* bits,
- size_t* storage_ix,
- uint8_t* storage) {
- size_t count = 0;
- size_t symbols[4] = { 0 };
- size_t length = 0;
- size_t total = histogram_total;
- while (total != 0) {
- if (histogram[length]) {
- if (count < 4) {
- symbols[count] = length;
- }
- ++count;
- total -= histogram[length];
- }
- ++length;
- }
-
- if (count <= 1) {
- BrotliWriteBits(4, 1, storage_ix, storage);
- BrotliWriteBits(max_bits, symbols[0], storage_ix, storage);
- depth[symbols[0]] = 0;
- bits[symbols[0]] = 0;
- return;
- }
-
- memset(depth, 0, length * sizeof(depth[0]));
- {
- const size_t max_tree_size = 2 * length + 1;
- HuffmanTree* tree = BROTLI_ALLOC(m, HuffmanTree, max_tree_size);
- uint32_t count_limit;
- if (BROTLI_IS_OOM(m)) return;
- for (count_limit = 1; ; count_limit *= 2) {
- HuffmanTree* node = tree;
- size_t l;
- for (l = length; l != 0;) {
- --l;
- if (histogram[l]) {
- if (PREDICT_TRUE(histogram[l] >= count_limit)) {
- InitHuffmanTree(node, histogram[l], -1, (int16_t)l);
- } else {
- InitHuffmanTree(node, count_limit, -1, (int16_t)l);
- }
- ++node;
- }
- }
- {
- const int n = (int)(node - tree);
- HuffmanTree sentinel;
- int i = 0; /* Points to the next leaf node. */
- int j = n + 1; /* Points to the next non-leaf node. */
- int k;
-
- SortHuffmanTreeItems(tree, (size_t)n, SortHuffmanTree);
- /* The nodes are:
- [0, n): the sorted leaf nodes that we start with.
- [n]: we add a sentinel here.
- [n + 1, 2n): new parent nodes are added here, starting from
- (n+1). These are naturally in ascending order.
- [2n]: we add a sentinel at the end as well.
- There will be (2n+1) elements at the end. */
- InitHuffmanTree(&sentinel, BROTLI_UINT32_MAX, -1, -1);
- *node++ = sentinel;
- *node++ = sentinel;
-
- for (k = n - 1; k > 0; --k) {
- int left, right;
- if (tree[i].total_count_ <= tree[j].total_count_) {
- left = i;
- ++i;
- } else {
- left = j;
- ++j;
- }
- if (tree[i].total_count_ <= tree[j].total_count_) {
- right = i;
- ++i;
- } else {
- right = j;
- ++j;
- }
- /* The sentinel node becomes the parent node. */
- node[-1].total_count_ =
- tree[left].total_count_ + tree[right].total_count_;
- node[-1].index_left_ = (int16_t)left;
- node[-1].index_right_or_value_ = (int16_t)right;
- /* Add back the last sentinel node. */
- *node++ = sentinel;
- }
- if (BrotliSetDepth(2 * n - 1, tree, depth, 14)) {
- /* We need to pack the Huffman tree in 14 bits. If this was not
- successful, add fake entities to the lowest values and retry. */
- break;
- }
- }
- }
- BROTLI_FREE(m, tree);
- }
- BrotliConvertBitDepthsToSymbols(depth, length, bits);
- if (count <= 4) {
- size_t i;
- /* value of 1 indicates a simple Huffman code */
- BrotliWriteBits(2, 1, storage_ix, storage);
- BrotliWriteBits(2, count - 1, storage_ix, storage); /* NSYM - 1 */
-
- /* Sort */
- for (i = 0; i < count; i++) {
- size_t j;
- for (j = i + 1; j < count; j++) {
- if (depth[symbols[j]] < depth[symbols[i]]) {
- BROTLI_SWAP(size_t, symbols, j, i);
- }
- }
- }
-
- if (count == 2) {
- BrotliWriteBits(max_bits, symbols[0], storage_ix, storage);
- BrotliWriteBits(max_bits, symbols[1], storage_ix, storage);
- } else if (count == 3) {
- BrotliWriteBits(max_bits, symbols[0], storage_ix, storage);
- BrotliWriteBits(max_bits, symbols[1], storage_ix, storage);
- BrotliWriteBits(max_bits, symbols[2], storage_ix, storage);
- } else {
- BrotliWriteBits(max_bits, symbols[0], storage_ix, storage);
- BrotliWriteBits(max_bits, symbols[1], storage_ix, storage);
- BrotliWriteBits(max_bits, symbols[2], storage_ix, storage);
- BrotliWriteBits(max_bits, symbols[3], storage_ix, storage);
- /* tree-select */
- BrotliWriteBits(1, depth[symbols[0]] == 1 ? 1 : 0, storage_ix, storage);
- }
- } else {
- uint8_t previous_value = 8;
- size_t i;
- /* Complex Huffman Tree */
- StoreStaticCodeLengthCode(storage_ix, storage);
-
- /* Actual rle coding. */
- for (i = 0; i < length;) {
- const uint8_t value = depth[i];
- size_t reps = 1;
- size_t k;
- for (k = i + 1; k < length && depth[k] == value; ++k) {
- ++reps;
- }
- i += reps;
- if (value == 0) {
- BrotliWriteBits(kZeroRepsDepth[reps], kZeroRepsBits[reps],
- storage_ix, storage);
- } else {
- if (previous_value != value) {
- BrotliWriteBits(kCodeLengthDepth[value], kCodeLengthBits[value],
- storage_ix, storage);
- --reps;
- }
- if (reps < 3) {
- while (reps != 0) {
- reps--;
- BrotliWriteBits(kCodeLengthDepth[value], kCodeLengthBits[value],
- storage_ix, storage);
- }
- } else {
- reps -= 3;
- BrotliWriteBits(kNonZeroRepsDepth[reps], kNonZeroRepsBits[reps],
- storage_ix, storage);
- }
- previous_value = value;
- }
- }
- }
-}
-
-static size_t IndexOf(const uint8_t* v, size_t v_size, uint8_t value) {
- size_t i = 0;
- for (; i < v_size; ++i) {
- if (v[i] == value) return i;
- }
- return i;
-}
-
-static void MoveToFront(uint8_t* v, size_t index) {
- uint8_t value = v[index];
- size_t i;
- for (i = index; i != 0; --i) {
- v[i] = v[i - 1];
- }
- v[0] = value;
-}
-
-static void MoveToFrontTransform(const uint32_t* BROTLI_RESTRICT v_in,
- const size_t v_size,
- uint32_t* v_out) {
- size_t i;
- uint8_t mtf[256];
- uint32_t max_value;
- if (v_size == 0) {
- return;
- }
- max_value = v_in[0];
- for (i = 1; i < v_size; ++i) {
- if (v_in[i] > max_value) max_value = v_in[i];
- }
- assert(max_value < 256u);
- for (i = 0; i <= max_value; ++i) {
- mtf[i] = (uint8_t)i;
- }
- {
- size_t mtf_size = max_value + 1;
- for (i = 0; i < v_size; ++i) {
- size_t index = IndexOf(mtf, mtf_size, (uint8_t)v_in[i]);
- assert(index < mtf_size);
- v_out[i] = (uint32_t)index;
- MoveToFront(mtf, index);
- }
- }
-}
-
-/* Finds runs of zeros in v[0..in_size) and replaces them with a prefix code of
- the run length plus extra bits (lower 9 bits is the prefix code and the rest
- are the extra bits). Non-zero values in v[] are shifted by
- *max_length_prefix. Will not create prefix codes bigger than the initial
- value of *max_run_length_prefix. The prefix code of run length L is simply
- Log2Floor(L) and the number of extra bits is the same as the prefix code. */
-static void RunLengthCodeZeros(const size_t in_size,
- uint32_t* BROTLI_RESTRICT v, size_t* BROTLI_RESTRICT out_size,
- uint32_t* BROTLI_RESTRICT max_run_length_prefix) {
- uint32_t max_reps = 0;
- size_t i;
- uint32_t max_prefix;
- for (i = 0; i < in_size;) {
- uint32_t reps = 0;
- for (; i < in_size && v[i] != 0; ++i) ;
- for (; i < in_size && v[i] == 0; ++i) {
- ++reps;
- }
- max_reps = BROTLI_MAX(uint32_t, reps, max_reps);
- }
- max_prefix = max_reps > 0 ? Log2FloorNonZero(max_reps) : 0;
- max_prefix = BROTLI_MIN(uint32_t, max_prefix, *max_run_length_prefix);
- *max_run_length_prefix = max_prefix;
- *out_size = 0;
- for (i = 0; i < in_size;) {
- assert(*out_size <= i);
- if (v[i] != 0) {
- v[*out_size] = v[i] + *max_run_length_prefix;
- ++i;
- ++(*out_size);
- } else {
- uint32_t reps = 1;
- size_t k;
- for (k = i + 1; k < in_size && v[k] == 0; ++k) {
- ++reps;
- }
- i += reps;
- while (reps != 0) {
- if (reps < (2u << max_prefix)) {
- uint32_t run_length_prefix = Log2FloorNonZero(reps);
- const uint32_t extra_bits = reps - (1u << run_length_prefix);
- v[*out_size] = run_length_prefix + (extra_bits << 9);
- ++(*out_size);
- break;
- } else {
- const uint32_t extra_bits = (1u << max_prefix) - 1u;
- v[*out_size] = max_prefix + (extra_bits << 9);
- reps -= (2u << max_prefix) - 1u;
- ++(*out_size);
- }
- }
- }
- }
-}
-
-#define SYMBOL_BITS 9
-
-static void EncodeContextMap(MemoryManager* m,
- const uint32_t* context_map,
- size_t context_map_size,
- size_t num_clusters,
- HuffmanTree* tree,
- size_t* storage_ix, uint8_t* storage) {
- size_t i;
- uint32_t* rle_symbols;
- uint32_t max_run_length_prefix = 6;
- size_t num_rle_symbols = 0;
- uint32_t histogram[BROTLI_MAX_CONTEXT_MAP_SYMBOLS];
- static const uint32_t kSymbolMask = (1u << SYMBOL_BITS) - 1u;
- uint8_t depths[BROTLI_MAX_CONTEXT_MAP_SYMBOLS];
- uint16_t bits[BROTLI_MAX_CONTEXT_MAP_SYMBOLS];
-
- StoreVarLenUint8(num_clusters - 1, storage_ix, storage);
-
- if (num_clusters == 1) {
- return;
- }
-
- rle_symbols = BROTLI_ALLOC(m, uint32_t, context_map_size);
- if (BROTLI_IS_OOM(m)) return;
- MoveToFrontTransform(context_map, context_map_size, rle_symbols);
- RunLengthCodeZeros(context_map_size, rle_symbols,
- &num_rle_symbols, &max_run_length_prefix);
- memset(histogram, 0, sizeof(histogram));
- for (i = 0; i < num_rle_symbols; ++i) {
- ++histogram[rle_symbols[i] & kSymbolMask];
- }
- {
- BROTLI_BOOL use_rle = TO_BROTLI_BOOL(max_run_length_prefix > 0);
- BrotliWriteBits(1, (uint64_t)use_rle, storage_ix, storage);
- if (use_rle) {
- BrotliWriteBits(4, max_run_length_prefix - 1, storage_ix, storage);
- }
- }
- BuildAndStoreHuffmanTree(histogram, num_clusters + max_run_length_prefix,
- tree, depths, bits, storage_ix, storage);
- for (i = 0; i < num_rle_symbols; ++i) {
- const uint32_t rle_symbol = rle_symbols[i] & kSymbolMask;
- const uint32_t extra_bits_val = rle_symbols[i] >> SYMBOL_BITS;
- BrotliWriteBits(depths[rle_symbol], bits[rle_symbol], storage_ix, storage);
- if (rle_symbol > 0 && rle_symbol <= max_run_length_prefix) {
- BrotliWriteBits(rle_symbol, extra_bits_val, storage_ix, storage);
- }
- }
- BrotliWriteBits(1, 1, storage_ix, storage); /* use move-to-front */
- BROTLI_FREE(m, rle_symbols);
-}
-
-/* Stores the block switch command with index block_ix to the bit stream. */
-static BROTLI_INLINE void StoreBlockSwitch(BlockSplitCode* code,
- const uint32_t block_len,
- const uint8_t block_type,
- BROTLI_BOOL is_first_block,
- size_t* storage_ix,
- uint8_t* storage) {
- size_t typecode = NextBlockTypeCode(&code->type_code_calculator, block_type);
- size_t lencode;
- uint32_t len_nextra;
- uint32_t len_extra;
- if (!is_first_block) {
- BrotliWriteBits(code->type_depths[typecode], code->type_bits[typecode],
- storage_ix, storage);
- }
- GetBlockLengthPrefixCode(block_len, &lencode, &len_nextra, &len_extra);
-
- BrotliWriteBits(code->length_depths[lencode], code->length_bits[lencode],
- storage_ix, storage);
- BrotliWriteBits(len_nextra, len_extra, storage_ix, storage);
-}
-
-/* Builds a BlockSplitCode data structure from the block split given by the
- vector of block types and block lengths and stores it to the bit stream. */
-static void BuildAndStoreBlockSplitCode(const uint8_t* types,
- const uint32_t* lengths,
- const size_t num_blocks,
- const size_t num_types,
- HuffmanTree* tree,
- BlockSplitCode* code,
- size_t* storage_ix,
- uint8_t* storage) {
- uint32_t type_histo[BROTLI_MAX_BLOCK_TYPE_SYMBOLS];
- uint32_t length_histo[BROTLI_NUM_BLOCK_LEN_SYMBOLS];
- size_t i;
- BlockTypeCodeCalculator type_code_calculator;
- memset(type_histo, 0, (num_types + 2) * sizeof(type_histo[0]));
- memset(length_histo, 0, sizeof(length_histo));
- InitBlockTypeCodeCalculator(&type_code_calculator);
- for (i = 0; i < num_blocks; ++i) {
- size_t type_code = NextBlockTypeCode(&type_code_calculator, types[i]);
- if (i != 0) ++type_histo[type_code];
- ++length_histo[BlockLengthPrefixCode(lengths[i])];
- }
- StoreVarLenUint8(num_types - 1, storage_ix, storage);
- if (num_types > 1) { /* TODO: else? could StoreBlockSwitch occur? */
- BuildAndStoreHuffmanTree(&type_histo[0], num_types + 2, tree,
- &code->type_depths[0], &code->type_bits[0],
- storage_ix, storage);
- BuildAndStoreHuffmanTree(&length_histo[0], BROTLI_NUM_BLOCK_LEN_SYMBOLS,
- tree, &code->length_depths[0],
- &code->length_bits[0], storage_ix, storage);
- StoreBlockSwitch(code, lengths[0], types[0], 1, storage_ix, storage);
- }
-}
-
-/* Stores a context map where the histogram type is always the block type. */
-static void StoreTrivialContextMap(size_t num_types,
- size_t context_bits,
- HuffmanTree* tree,
- size_t* storage_ix,
- uint8_t* storage) {
- StoreVarLenUint8(num_types - 1, storage_ix, storage);
- if (num_types > 1) {
- size_t repeat_code = context_bits - 1u;
- size_t repeat_bits = (1u << repeat_code) - 1u;
- size_t alphabet_size = num_types + repeat_code;
- uint32_t histogram[BROTLI_MAX_CONTEXT_MAP_SYMBOLS];
- uint8_t depths[BROTLI_MAX_CONTEXT_MAP_SYMBOLS];
- uint16_t bits[BROTLI_MAX_CONTEXT_MAP_SYMBOLS];
- size_t i;
- memset(histogram, 0, alphabet_size * sizeof(histogram[0]));
- /* Write RLEMAX. */
- BrotliWriteBits(1, 1, storage_ix, storage);
- BrotliWriteBits(4, repeat_code - 1, storage_ix, storage);
- histogram[repeat_code] = (uint32_t)num_types;
- histogram[0] = 1;
- for (i = context_bits; i < alphabet_size; ++i) {
- histogram[i] = 1;
- }
- BuildAndStoreHuffmanTree(histogram, alphabet_size, tree,
- depths, bits, storage_ix, storage);
- for (i = 0; i < num_types; ++i) {
- size_t code = (i == 0 ? 0 : i + context_bits - 1);
- BrotliWriteBits(depths[code], bits[code], storage_ix, storage);
- BrotliWriteBits(
- depths[repeat_code], bits[repeat_code], storage_ix, storage);
- BrotliWriteBits(repeat_code, repeat_bits, storage_ix, storage);
- }
- /* Write IMTF (inverse-move-to-front) bit. */
- BrotliWriteBits(1, 1, storage_ix, storage);
- }
-}
-
-/* Manages the encoding of one block category (literal, command or distance). */
-typedef struct BlockEncoder {
- size_t alphabet_size_;
- size_t num_block_types_;
- const uint8_t* block_types_; /* Not owned. */
- const uint32_t* block_lengths_; /* Not owned. */
- size_t num_blocks_;
- BlockSplitCode block_split_code_;
- size_t block_ix_;
- size_t block_len_;
- size_t entropy_ix_;
- uint8_t* depths_;
- uint16_t* bits_;
-} BlockEncoder;
-
-static void InitBlockEncoder(BlockEncoder* self, size_t alphabet_size,
- size_t num_block_types, const uint8_t* block_types,
- const uint32_t* block_lengths, const size_t num_blocks) {
- self->alphabet_size_ = alphabet_size;
- self->num_block_types_ = num_block_types;
- self->block_types_ = block_types;
- self->block_lengths_ = block_lengths;
- self->num_blocks_ = num_blocks;
- InitBlockTypeCodeCalculator(&self->block_split_code_.type_code_calculator);
- self->block_ix_ = 0;
- self->block_len_ = num_blocks == 0 ? 0 : block_lengths[0];
- self->entropy_ix_ = 0;
- self->depths_ = 0;
- self->bits_ = 0;
-}
-
-static void CleanupBlockEncoder(MemoryManager* m, BlockEncoder* self) {
- BROTLI_FREE(m, self->depths_);
- BROTLI_FREE(m, self->bits_);
-}
-
-/* Creates entropy codes of block lengths and block types and stores them
- to the bit stream. */
-static void BuildAndStoreBlockSwitchEntropyCodes(BlockEncoder* self,
- HuffmanTree* tree, size_t* storage_ix, uint8_t* storage) {
- BuildAndStoreBlockSplitCode(self->block_types_, self->block_lengths_,
- self->num_blocks_, self->num_block_types_, tree, &self->block_split_code_,
- storage_ix, storage);
-}
-
-/* Stores the next symbol with the entropy code of the current block type.
- Updates the block type and block length at block boundaries. */
-static void StoreSymbol(BlockEncoder* self, size_t symbol, size_t* storage_ix,
- uint8_t* storage) {
- if (self->block_len_ == 0) {
- size_t block_ix = ++self->block_ix_;
- uint32_t block_len = self->block_lengths_[block_ix];
- uint8_t block_type = self->block_types_[block_ix];
- self->block_len_ = block_len;
- self->entropy_ix_ = block_type * self->alphabet_size_;
- StoreBlockSwitch(&self->block_split_code_, block_len, block_type, 0,
- storage_ix, storage);
- }
- --self->block_len_;
- {
- size_t ix = self->entropy_ix_ + symbol;
- BrotliWriteBits(self->depths_[ix], self->bits_[ix], storage_ix, storage);
- }
-}
-
-/* Stores the next symbol with the entropy code of the current block type and
- context value.
- Updates the block type and block length at block boundaries. */
-static void StoreSymbolWithContext(BlockEncoder* self, size_t symbol,
- size_t context, const uint32_t* context_map, size_t* storage_ix,
- uint8_t* storage, const size_t context_bits) {
- if (self->block_len_ == 0) {
- size_t block_ix = ++self->block_ix_;
- uint32_t block_len = self->block_lengths_[block_ix];
- uint8_t block_type = self->block_types_[block_ix];
- self->block_len_ = block_len;
- self->entropy_ix_ = (size_t)block_type << context_bits;
- StoreBlockSwitch(&self->block_split_code_, block_len, block_type, 0,
- storage_ix, storage);
- }
- --self->block_len_;
- {
- size_t histo_ix = context_map[self->entropy_ix_ + context];
- size_t ix = histo_ix * self->alphabet_size_ + symbol;
- BrotliWriteBits(self->depths_[ix], self->bits_[ix], storage_ix, storage);
- }
-}
-
-#define FN(X) X ## Literal
-/* NOLINTNEXTLINE(build/include) */
-#include "./block_encoder_inc.h"
-#undef FN
-
-#define FN(X) X ## Command
-/* NOLINTNEXTLINE(build/include) */
-#include "./block_encoder_inc.h"
-#undef FN
-
-#define FN(X) X ## Distance
-/* NOLINTNEXTLINE(build/include) */
-#include "./block_encoder_inc.h"
-#undef FN
-
-static void JumpToByteBoundary(size_t* storage_ix, uint8_t* storage) {
- *storage_ix = (*storage_ix + 7u) & ~7u;
- storage[*storage_ix >> 3] = 0;
-}
-
-void BrotliStoreMetaBlock(MemoryManager* m,
- const uint8_t* input,
- size_t start_pos,
- size_t length,
- size_t mask,
- uint8_t prev_byte,
- uint8_t prev_byte2,
- BROTLI_BOOL is_last,
- uint32_t num_direct_distance_codes,
- uint32_t distance_postfix_bits,
- ContextType literal_context_mode,
- const Command *commands,
- size_t n_commands,
- const MetaBlockSplit* mb,
- size_t *storage_ix,
- uint8_t *storage) {
- size_t pos = start_pos;
- size_t i;
- size_t num_distance_codes =
- BROTLI_NUM_DISTANCE_SHORT_CODES + num_direct_distance_codes +
- (48u << distance_postfix_bits);
- HuffmanTree* tree;
- BlockEncoder literal_enc;
- BlockEncoder command_enc;
- BlockEncoder distance_enc;
-
- StoreCompressedMetaBlockHeader(is_last, length, storage_ix, storage);
-
- tree = BROTLI_ALLOC(m, HuffmanTree, MAX_HUFFMAN_TREE_SIZE);
- if (BROTLI_IS_OOM(m)) return;
- InitBlockEncoder(&literal_enc, 256, mb->literal_split.num_types,
- mb->literal_split.types, mb->literal_split.lengths,
- mb->literal_split.num_blocks);
- InitBlockEncoder(&command_enc, BROTLI_NUM_COMMAND_SYMBOLS,
- mb->command_split.num_types, mb->command_split.types,
- mb->command_split.lengths, mb->command_split.num_blocks);
- InitBlockEncoder(&distance_enc, num_distance_codes,
- mb->distance_split.num_types, mb->distance_split.types,
- mb->distance_split.lengths, mb->distance_split.num_blocks);
-
- BuildAndStoreBlockSwitchEntropyCodes(&literal_enc, tree, storage_ix, storage);
- BuildAndStoreBlockSwitchEntropyCodes(&command_enc, tree, storage_ix, storage);
- BuildAndStoreBlockSwitchEntropyCodes(
- &distance_enc, tree, storage_ix, storage);
-
- BrotliWriteBits(2, distance_postfix_bits, storage_ix, storage);
- BrotliWriteBits(4, num_direct_distance_codes >> distance_postfix_bits,
- storage_ix, storage);
- for (i = 0; i < mb->literal_split.num_types; ++i) {
- BrotliWriteBits(2, literal_context_mode, storage_ix, storage);
- }
-
- if (mb->literal_context_map_size == 0) {
- StoreTrivialContextMap(mb->literal_histograms_size,
- BROTLI_LITERAL_CONTEXT_BITS, tree, storage_ix, storage);
- } else {
- EncodeContextMap(m,
- mb->literal_context_map, mb->literal_context_map_size,
- mb->literal_histograms_size, tree, storage_ix, storage);
- if (BROTLI_IS_OOM(m)) return;
- }
-
- if (mb->distance_context_map_size == 0) {
- StoreTrivialContextMap(mb->distance_histograms_size,
- BROTLI_DISTANCE_CONTEXT_BITS, tree, storage_ix, storage);
- } else {
- EncodeContextMap(m,
- mb->distance_context_map, mb->distance_context_map_size,
- mb->distance_histograms_size, tree, storage_ix, storage);
- if (BROTLI_IS_OOM(m)) return;
- }
-
- BuildAndStoreEntropyCodesLiteral(m, &literal_enc, mb->literal_histograms,
- mb->literal_histograms_size, tree, storage_ix, storage);
- if (BROTLI_IS_OOM(m)) return;
- BuildAndStoreEntropyCodesCommand(m, &command_enc, mb->command_histograms,
- mb->command_histograms_size, tree, storage_ix, storage);
- if (BROTLI_IS_OOM(m)) return;
- BuildAndStoreEntropyCodesDistance(m, &distance_enc, mb->distance_histograms,
- mb->distance_histograms_size, tree, storage_ix, storage);
- if (BROTLI_IS_OOM(m)) return;
- BROTLI_FREE(m, tree);
-
- for (i = 0; i < n_commands; ++i) {
- const Command cmd = commands[i];
- size_t cmd_code = cmd.cmd_prefix_;
- StoreSymbol(&command_enc, cmd_code, storage_ix, storage);
- StoreCommandExtra(&cmd, storage_ix, storage);
- if (mb->literal_context_map_size == 0) {
- size_t j;
- for (j = cmd.insert_len_; j != 0; --j) {
- StoreSymbol(&literal_enc, input[pos & mask], storage_ix, storage);
- ++pos;
- }
- } else {
- size_t j;
- for (j = cmd.insert_len_; j != 0; --j) {
- size_t context = Context(prev_byte, prev_byte2, literal_context_mode);
- uint8_t literal = input[pos & mask];
- StoreSymbolWithContext(&literal_enc, literal, context,
- mb->literal_context_map, storage_ix, storage,
- BROTLI_LITERAL_CONTEXT_BITS);
- prev_byte2 = prev_byte;
- prev_byte = literal;
- ++pos;
- }
- }
- pos += CommandCopyLen(&cmd);
- if (CommandCopyLen(&cmd)) {
- prev_byte2 = input[(pos - 2) & mask];
- prev_byte = input[(pos - 1) & mask];
- if (cmd.cmd_prefix_ >= 128) {
- size_t dist_code = cmd.dist_prefix_;
- uint32_t distnumextra = cmd.dist_extra_ >> 24;
- uint64_t distextra = cmd.dist_extra_ & 0xffffff;
- if (mb->distance_context_map_size == 0) {
- StoreSymbol(&distance_enc, dist_code, storage_ix, storage);
- } else {
- size_t context = CommandDistanceContext(&cmd);
- StoreSymbolWithContext(&distance_enc, dist_code, context,
- mb->distance_context_map, storage_ix, storage,
- BROTLI_DISTANCE_CONTEXT_BITS);
- }
- BrotliWriteBits(distnumextra, distextra, storage_ix, storage);
- }
- }
- }
- CleanupBlockEncoder(m, &distance_enc);
- CleanupBlockEncoder(m, &command_enc);
- CleanupBlockEncoder(m, &literal_enc);
- if (is_last) {
- JumpToByteBoundary(storage_ix, storage);
- }
-}
-
-static void BuildHistograms(const uint8_t* input,
- size_t start_pos,
- size_t mask,
- const Command *commands,
- size_t n_commands,
- HistogramLiteral* lit_histo,
- HistogramCommand* cmd_histo,
- HistogramDistance* dist_histo) {
- size_t pos = start_pos;
- size_t i;
- for (i = 0; i < n_commands; ++i) {
- const Command cmd = commands[i];
- size_t j;
- HistogramAddCommand(cmd_histo, cmd.cmd_prefix_);
- for (j = cmd.insert_len_; j != 0; --j) {
- HistogramAddLiteral(lit_histo, input[pos & mask]);
- ++pos;
- }
- pos += CommandCopyLen(&cmd);
- if (CommandCopyLen(&cmd) && cmd.cmd_prefix_ >= 128) {
- HistogramAddDistance(dist_histo, cmd.dist_prefix_);
- }
- }
-}
-
-static void StoreDataWithHuffmanCodes(const uint8_t* input,
- size_t start_pos,
- size_t mask,
- const Command *commands,
- size_t n_commands,
- const uint8_t* lit_depth,
- const uint16_t* lit_bits,
- const uint8_t* cmd_depth,
- const uint16_t* cmd_bits,
- const uint8_t* dist_depth,
- const uint16_t* dist_bits,
- size_t* storage_ix,
- uint8_t* storage) {
- size_t pos = start_pos;
- size_t i;
- for (i = 0; i < n_commands; ++i) {
- const Command cmd = commands[i];
- const size_t cmd_code = cmd.cmd_prefix_;
- size_t j;
- BrotliWriteBits(
- cmd_depth[cmd_code], cmd_bits[cmd_code], storage_ix, storage);
- StoreCommandExtra(&cmd, storage_ix, storage);
- for (j = cmd.insert_len_; j != 0; --j) {
- const uint8_t literal = input[pos & mask];
- BrotliWriteBits(
- lit_depth[literal], lit_bits[literal], storage_ix, storage);
- ++pos;
- }
- pos += CommandCopyLen(&cmd);
- if (CommandCopyLen(&cmd) && cmd.cmd_prefix_ >= 128) {
- const size_t dist_code = cmd.dist_prefix_;
- const uint32_t distnumextra = cmd.dist_extra_ >> 24;
- const uint32_t distextra = cmd.dist_extra_ & 0xffffff;
- BrotliWriteBits(dist_depth[dist_code], dist_bits[dist_code],
- storage_ix, storage);
- BrotliWriteBits(distnumextra, distextra, storage_ix, storage);
- }
- }
-}
-
-void BrotliStoreMetaBlockTrivial(MemoryManager* m,
- const uint8_t* input,
- size_t start_pos,
- size_t length,
- size_t mask,
- BROTLI_BOOL is_last,
- const Command *commands,
- size_t n_commands,
- size_t *storage_ix,
- uint8_t *storage) {
- HistogramLiteral lit_histo;
- HistogramCommand cmd_histo;
- HistogramDistance dist_histo;
- uint8_t lit_depth[256];
- uint16_t lit_bits[256];
- uint8_t cmd_depth[BROTLI_NUM_COMMAND_SYMBOLS];
- uint16_t cmd_bits[BROTLI_NUM_COMMAND_SYMBOLS];
- uint8_t dist_depth[64];
- uint16_t dist_bits[64];
- HuffmanTree* tree;
-
- StoreCompressedMetaBlockHeader(is_last, length, storage_ix, storage);
-
- HistogramClearLiteral(&lit_histo);
- HistogramClearCommand(&cmd_histo);
- HistogramClearDistance(&dist_histo);
-
- BuildHistograms(input, start_pos, mask, commands, n_commands,
- &lit_histo, &cmd_histo, &dist_histo);
-
- BrotliWriteBits(13, 0, storage_ix, storage);
-
- tree = BROTLI_ALLOC(m, HuffmanTree, MAX_HUFFMAN_TREE_SIZE);
- if (BROTLI_IS_OOM(m)) return;
- BuildAndStoreHuffmanTree(lit_histo.data_, 256, tree,
- lit_depth, lit_bits,
- storage_ix, storage);
- BuildAndStoreHuffmanTree(cmd_histo.data_, BROTLI_NUM_COMMAND_SYMBOLS, tree,
- cmd_depth, cmd_bits,
- storage_ix, storage);
- BuildAndStoreHuffmanTree(dist_histo.data_, 64, tree,
- dist_depth, dist_bits,
- storage_ix, storage);
- BROTLI_FREE(m, tree);
- StoreDataWithHuffmanCodes(input, start_pos, mask, commands,
- n_commands, lit_depth, lit_bits,
- cmd_depth, cmd_bits,
- dist_depth, dist_bits,
- storage_ix, storage);
- if (is_last) {
- JumpToByteBoundary(storage_ix, storage);
- }
-}
-
-void BrotliStoreMetaBlockFast(MemoryManager* m,
- const uint8_t* input,
- size_t start_pos,
- size_t length,
- size_t mask,
- BROTLI_BOOL is_last,
- const Command *commands,
- size_t n_commands,
- size_t *storage_ix,
- uint8_t *storage) {
- StoreCompressedMetaBlockHeader(is_last, length, storage_ix, storage);
-
- BrotliWriteBits(13, 0, storage_ix, storage);
-
- if (n_commands <= 128) {
- uint32_t histogram[BROTLI_NUM_LITERAL_SYMBOLS] = { 0 };
- size_t pos = start_pos;
- size_t num_literals = 0;
- size_t i;
- uint8_t lit_depth[BROTLI_NUM_LITERAL_SYMBOLS];
- uint16_t lit_bits[BROTLI_NUM_LITERAL_SYMBOLS];
- for (i = 0; i < n_commands; ++i) {
- const Command cmd = commands[i];
- size_t j;
- for (j = cmd.insert_len_; j != 0; --j) {
- ++histogram[input[pos & mask]];
- ++pos;
- }
- num_literals += cmd.insert_len_;
- pos += CommandCopyLen(&cmd);
- }
- BrotliBuildAndStoreHuffmanTreeFast(m, histogram, num_literals,
- /* max_bits = */ 8,
- lit_depth, lit_bits,
- storage_ix, storage);
- if (BROTLI_IS_OOM(m)) return;
- StoreStaticCommandHuffmanTree(storage_ix, storage);
- StoreStaticDistanceHuffmanTree(storage_ix, storage);
- StoreDataWithHuffmanCodes(input, start_pos, mask, commands,
- n_commands, lit_depth, lit_bits,
- kStaticCommandCodeDepth,
- kStaticCommandCodeBits,
- kStaticDistanceCodeDepth,
- kStaticDistanceCodeBits,
- storage_ix, storage);
- } else {
- HistogramLiteral lit_histo;
- HistogramCommand cmd_histo;
- HistogramDistance dist_histo;
- uint8_t lit_depth[BROTLI_NUM_LITERAL_SYMBOLS];
- uint16_t lit_bits[BROTLI_NUM_LITERAL_SYMBOLS];
- uint8_t cmd_depth[BROTLI_NUM_COMMAND_SYMBOLS];
- uint16_t cmd_bits[BROTLI_NUM_COMMAND_SYMBOLS];
- uint8_t dist_depth[64];
- uint16_t dist_bits[64];
- HistogramClearLiteral(&lit_histo);
- HistogramClearCommand(&cmd_histo);
- HistogramClearDistance(&dist_histo);
- BuildHistograms(input, start_pos, mask, commands, n_commands,
- &lit_histo, &cmd_histo, &dist_histo);
- BrotliBuildAndStoreHuffmanTreeFast(m, lit_histo.data_,
- lit_histo.total_count_,
- /* max_bits = */ 8,
- lit_depth, lit_bits,
- storage_ix, storage);
- if (BROTLI_IS_OOM(m)) return;
- BrotliBuildAndStoreHuffmanTreeFast(m, cmd_histo.data_,
- cmd_histo.total_count_,
- /* max_bits = */ 10,
- cmd_depth, cmd_bits,
- storage_ix, storage);
- if (BROTLI_IS_OOM(m)) return;
- BrotliBuildAndStoreHuffmanTreeFast(m, dist_histo.data_,
- dist_histo.total_count_,
- /* max_bits = */ 6,
- dist_depth, dist_bits,
- storage_ix, storage);
- if (BROTLI_IS_OOM(m)) return;
- StoreDataWithHuffmanCodes(input, start_pos, mask, commands,
- n_commands, lit_depth, lit_bits,
- cmd_depth, cmd_bits,
- dist_depth, dist_bits,
- storage_ix, storage);
- }
-
- if (is_last) {
- JumpToByteBoundary(storage_ix, storage);
- }
-}
-
-/* This is for storing uncompressed blocks (simple raw storage of
- bytes-as-bytes). */
-void BrotliStoreUncompressedMetaBlock(BROTLI_BOOL is_final_block,
- const uint8_t * BROTLI_RESTRICT input,
- size_t position, size_t mask,
- size_t len,
- size_t * BROTLI_RESTRICT storage_ix,
- uint8_t * BROTLI_RESTRICT storage) {
- size_t masked_pos = position & mask;
- BrotliStoreUncompressedMetaBlockHeader(len, storage_ix, storage);
- JumpToByteBoundary(storage_ix, storage);
-
- if (masked_pos + len > mask + 1) {
- size_t len1 = mask + 1 - masked_pos;
- memcpy(&storage[*storage_ix >> 3], &input[masked_pos], len1);
- *storage_ix += len1 << 3;
- len -= len1;
- masked_pos = 0;
- }
- memcpy(&storage[*storage_ix >> 3], &input[masked_pos], len);
- *storage_ix += len << 3;
-
- /* We need to clear the next 4 bytes to continue to be
- compatible with BrotliWriteBits. */
- BrotliWriteBitsPrepareStorage(*storage_ix, storage);
-
- /* Since the uncompressed block itself may not be the final block, add an
- empty one after this. */
- if (is_final_block) {
- BrotliWriteBits(1, 1, storage_ix, storage); /* islast */
- BrotliWriteBits(1, 1, storage_ix, storage); /* isempty */
- JumpToByteBoundary(storage_ix, storage);
- }
-}
-
-void BrotliStoreSyncMetaBlock(size_t* BROTLI_RESTRICT storage_ix,
- uint8_t* BROTLI_RESTRICT storage) {
- /* Empty metadata meta-block bit pattern:
- 1 bit: is_last (0)
- 2 bits: num nibbles (3)
- 1 bit: reserved (0)
- 2 bits: metadata length bytes (0) */
- BrotliWriteBits(6, 6, storage_ix, storage);
- JumpToByteBoundary(storage_ix, storage);
-}
-
-
-#if defined(__cplusplus) || defined(c_plusplus)
-} /* extern "C" */
-#endif
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