1/* Copyright 2015 Google Inc. All Rights Reserved. 2 3 Distributed under MIT license. 4 See file LICENSE for detail or copy at https://opensource.org/licenses/MIT 5*/ 6 7#include "./state.h" 8 9#include <stdlib.h> /* free, malloc */ 10 11#include <brotli/types.h> 12#include "./huffman.h" 13 14#if defined(__cplusplus) || defined(c_plusplus) 15extern "C" { 16#endif 17 18BROTLI_BOOL BrotliDecoderStateInit(BrotliDecoderState* s, 19 brotli_alloc_func alloc_func, brotli_free_func free_func, void* opaque) { 20 if (!alloc_func) { 21 s->alloc_func = BrotliDefaultAllocFunc; 22 s->free_func = BrotliDefaultFreeFunc; 23 s->memory_manager_opaque = 0; 24 } else { 25 s->alloc_func = alloc_func; 26 s->free_func = free_func; 27 s->memory_manager_opaque = opaque; 28 } 29 30 s->error_code = 0; /* BROTLI_DECODER_NO_ERROR */ 31 32 BrotliInitBitReader(&s->br); 33 s->state = BROTLI_STATE_UNINITED; 34 s->large_window = 0; 35 s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_NONE; 36 s->substate_uncompressed = BROTLI_STATE_UNCOMPRESSED_NONE; 37 s->substate_decode_uint8 = BROTLI_STATE_DECODE_UINT8_NONE; 38 s->substate_read_block_length = BROTLI_STATE_READ_BLOCK_LENGTH_NONE; 39 40 s->buffer_length = 0; 41 s->loop_counter = 0; 42 s->pos = 0; 43 s->rb_roundtrips = 0; 44 s->partial_pos_out = 0; 45 46 s->block_type_trees = NULL; 47 s->block_len_trees = NULL; 48 s->ringbuffer = NULL; 49 s->ringbuffer_size = 0; 50 s->new_ringbuffer_size = 0; 51 s->ringbuffer_mask = 0; 52 53 s->context_map = NULL; 54 s->context_modes = NULL; 55 s->dist_context_map = NULL; 56 s->context_map_slice = NULL; 57 s->dist_context_map_slice = NULL; 58 59 s->literal_hgroup.codes = NULL; 60 s->literal_hgroup.htrees = NULL; 61 s->insert_copy_hgroup.codes = NULL; 62 s->insert_copy_hgroup.htrees = NULL; 63 s->distance_hgroup.codes = NULL; 64 s->distance_hgroup.htrees = NULL; 65 66 s->is_last_metablock = 0; 67 s->is_uncompressed = 0; 68 s->is_metadata = 0; 69 s->should_wrap_ringbuffer = 0; 70 s->canny_ringbuffer_allocation = 1; 71 72 s->window_bits = 0; 73 s->max_distance = 0; 74 s->dist_rb[0] = 16; 75 s->dist_rb[1] = 15; 76 s->dist_rb[2] = 11; 77 s->dist_rb[3] = 4; 78 s->dist_rb_idx = 0; 79 s->block_type_trees = NULL; 80 s->block_len_trees = NULL; 81 82 s->mtf_upper_bound = 63; 83 84 s->dictionary = BrotliGetDictionary(); 85 s->transforms = BrotliGetTransforms(); 86 87 return BROTLI_TRUE; 88} 89 90void BrotliDecoderStateMetablockBegin(BrotliDecoderState* s) { 91 s->meta_block_remaining_len = 0; 92 s->block_length[0] = 1U << 24; 93 s->block_length[1] = 1U << 24; 94 s->block_length[2] = 1U << 24; 95 s->num_block_types[0] = 1; 96 s->num_block_types[1] = 1; 97 s->num_block_types[2] = 1; 98 s->block_type_rb[0] = 1; 99 s->block_type_rb[1] = 0; 100 s->block_type_rb[2] = 1; 101 s->block_type_rb[3] = 0; 102 s->block_type_rb[4] = 1; 103 s->block_type_rb[5] = 0; 104 s->context_map = NULL; 105 s->context_modes = NULL; 106 s->dist_context_map = NULL; 107 s->context_map_slice = NULL; 108 s->literal_htree = NULL; 109 s->dist_context_map_slice = NULL; 110 s->dist_htree_index = 0; 111 s->context_lookup = NULL; 112 s->literal_hgroup.codes = NULL; 113 s->literal_hgroup.htrees = NULL; 114 s->insert_copy_hgroup.codes = NULL; 115 s->insert_copy_hgroup.htrees = NULL; 116 s->distance_hgroup.codes = NULL; 117 s->distance_hgroup.htrees = NULL; 118} 119 120void BrotliDecoderStateCleanupAfterMetablock(BrotliDecoderState* s) { 121 BROTLI_DECODER_FREE(s, s->context_modes); 122 BROTLI_DECODER_FREE(s, s->context_map); 123 BROTLI_DECODER_FREE(s, s->dist_context_map); 124 BROTLI_DECODER_FREE(s, s->literal_hgroup.htrees); 125 BROTLI_DECODER_FREE(s, s->insert_copy_hgroup.htrees); 126 BROTLI_DECODER_FREE(s, s->distance_hgroup.htrees); 127} 128 129void BrotliDecoderStateCleanup(BrotliDecoderState* s) { 130 BrotliDecoderStateCleanupAfterMetablock(s); 131 132 BROTLI_DECODER_FREE(s, s->ringbuffer); 133 BROTLI_DECODER_FREE(s, s->block_type_trees); 134} 135 136BROTLI_BOOL BrotliDecoderHuffmanTreeGroupInit(BrotliDecoderState* s, 137 HuffmanTreeGroup* group, uint32_t alphabet_size_max, 138 uint32_t alphabet_size_limit, uint32_t ntrees) { 139 /* 376 = 256 (1-st level table) + 4 + 7 + 15 + 31 + 63 (2-nd level mix-tables) 140 This number is discovered "unlimited" "enough" calculator; it is actually 141 a wee bigger than required in several cases (especially for alphabets with 142 less than 16 symbols). */ 143 const size_t max_table_size = alphabet_size_limit + 376; 144 const size_t code_size = sizeof(HuffmanCode) * ntrees * max_table_size; 145 const size_t htree_size = sizeof(HuffmanCode*) * ntrees; 146 /* Pointer alignment is, hopefully, wider than sizeof(HuffmanCode). */ 147 HuffmanCode** p = (HuffmanCode**)BROTLI_DECODER_ALLOC(s, 148 code_size + htree_size); 149 group->alphabet_size_max = (uint16_t)alphabet_size_max; 150 group->alphabet_size_limit = (uint16_t)alphabet_size_limit; 151 group->num_htrees = (uint16_t)ntrees; 152 group->htrees = p; 153 group->codes = (HuffmanCode*)(&p[ntrees]); 154 return !!p; 155} 156 157#if defined(__cplusplus) || defined(c_plusplus) 158} /* extern "C" */ 159#endif 160