Hash :
35e69fc7
Author :
Date :
2018-02-26T09:04:36
New feature: "Large Window Brotli" (#640) * New feature: "Large Window Brotli" By setting special encoder/decoder flag it is now possible to extend LZ-window up to 30 bits; though produced stream will not be RFC7932 compliant. Added new dictionary generator - "DSH". It combines speed of "Sieve" and quality of "DM". Plus utilities to prepare train corpora (remove unique strings). Improved compression ratio: now two sub-blocks could be stitched: the last copy command could be extended to span the next sub-block. Fixed compression ineffectiveness caused by floating numbers rounding and wrong cost heuristic. Other C changes: - combined / moved `context.h` to `common` - moved transforms to `common` - unified some aspects of code formatting - added an abstraction for encoder (static) dictionary - moved default allocator/deallocator functions to `common` brotli CLI: - window size is auto-adjusted if not specified explicitly Java: - added "eager" decoding both to JNI wrapper and pure decoder - huge speed-up of `DictionaryData` initialization * Add dictionaryless compressed dictionary * Fix `sources.lst` * Fix `sources.lst` and add a note that `libtool` is also required. * Update setup.py * Fix `EagerStreamTest` * Fix BUILD file * Add missing `libdivsufsort` dependency * Fix "unused parameter" warning.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164
/* Copyright 2015 Google Inc. All Rights Reserved.
Distributed under MIT license.
See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
*/
#include "./state.h"
#include <stdlib.h> /* free, malloc */
#include <brotli/types.h>
#include "./huffman.h"
#if defined(__cplusplus) || defined(c_plusplus)
extern "C" {
#endif
BROTLI_BOOL BrotliDecoderStateInit(BrotliDecoderState* s,
brotli_alloc_func alloc_func, brotli_free_func free_func, void* opaque) {
if (!alloc_func) {
s->alloc_func = BrotliDefaultAllocFunc;
s->free_func = BrotliDefaultFreeFunc;
s->memory_manager_opaque = 0;
} else {
s->alloc_func = alloc_func;
s->free_func = free_func;
s->memory_manager_opaque = opaque;
}
s->error_code = 0; /* BROTLI_DECODER_NO_ERROR */
BrotliInitBitReader(&s->br);
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;
s->buffer_length = 0;
s->loop_counter = 0;
s->pos = 0;
s->rb_roundtrips = 0;
s->partial_pos_out = 0;
s->block_type_trees = NULL;
s->block_len_trees = NULL;
s->ringbuffer = NULL;
s->ringbuffer_size = 0;
s->new_ringbuffer_size = 0;
s->ringbuffer_mask = 0;
s->context_map = NULL;
s->context_modes = NULL;
s->dist_context_map = NULL;
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;
s->insert_copy_hgroup.htrees = NULL;
s->distance_hgroup.codes = NULL;
s->distance_hgroup.htrees = NULL;
s->is_last_metablock = 0;
s->is_uncompressed = 0;
s->is_metadata = 0;
s->should_wrap_ringbuffer = 0;
s->canny_ringbuffer_allocation = 1;
s->window_bits = 0;
s->max_distance = 0;
s->dist_rb[0] = 16;
s->dist_rb[1] = 15;
s->dist_rb[2] = 11;
s->dist_rb[3] = 4;
s->dist_rb_idx = 0;
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();
s->transforms = BrotliGetTransforms();
return BROTLI_TRUE;
}
void BrotliDecoderStateMetablockBegin(BrotliDecoderState* s) {
s->meta_block_remaining_len = 0;
s->block_length[0] = 1U << 24;
s->block_length[1] = 1U << 24;
s->block_length[2] = 1U << 24;
s->num_block_types[0] = 1;
s->num_block_types[1] = 1;
s->num_block_types[2] = 1;
s->block_type_rb[0] = 1;
s->block_type_rb[1] = 0;
s->block_type_rb[2] = 1;
s->block_type_rb[3] = 0;
s->block_type_rb[4] = 1;
s->block_type_rb[5] = 0;
s->context_map = NULL;
s->context_modes = NULL;
s->dist_context_map = NULL;
s->context_map_slice = NULL;
s->literal_htree = NULL;
s->dist_context_map_slice = NULL;
s->dist_htree_index = 0;
s->context_lookup = NULL;
s->literal_hgroup.codes = NULL;
s->literal_hgroup.htrees = NULL;
s->insert_copy_hgroup.codes = NULL;
s->insert_copy_hgroup.htrees = NULL;
s->distance_hgroup.codes = NULL;
s->distance_hgroup.htrees = NULL;
}
void BrotliDecoderStateCleanupAfterMetablock(BrotliDecoderState* s) {
BROTLI_DECODER_FREE(s, s->context_modes);
BROTLI_DECODER_FREE(s, s->context_map);
BROTLI_DECODER_FREE(s, s->dist_context_map);
BROTLI_DECODER_FREE(s, s->literal_hgroup.htrees);
BROTLI_DECODER_FREE(s, s->insert_copy_hgroup.htrees);
BROTLI_DECODER_FREE(s, s->distance_hgroup.htrees);
}
void BrotliDecoderStateCleanup(BrotliDecoderState* s) {
BrotliDecoderStateCleanupAfterMetablock(s);
BROTLI_DECODER_FREE(s, s->ringbuffer);
BROTLI_DECODER_FREE(s, s->block_type_trees);
}
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];
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->num_htrees = (uint16_t)ntrees;
group->htrees = p;
group->codes = (HuffmanCode*)(&p[ntrees]);
return !!p;
}
#if defined(__cplusplus) || defined(c_plusplus)
} /* extern "C" */
#endif