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) 15 extern "C" { 16 #endif 17 18 BROTLI_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_tree_group = BROTLI_STATE_TREE_GROUP_NONE; 37 s->substate_context_map = BROTLI_STATE_CONTEXT_MAP_NONE; 38 s->substate_uncompressed = BROTLI_STATE_UNCOMPRESSED_NONE; 39 s->substate_huffman = BROTLI_STATE_HUFFMAN_NONE; 40 s->substate_decode_uint8 = BROTLI_STATE_DECODE_UINT8_NONE; 41 s->substate_read_block_length = BROTLI_STATE_READ_BLOCK_LENGTH_NONE; 42 43 s->buffer_length = 0; 44 s->loop_counter = 0; 45 s->pos = 0; 46 s->rb_roundtrips = 0; 47 s->partial_pos_out = 0; 48 49 s->block_type_trees = NULL; 50 s->block_len_trees = NULL; 51 s->ringbuffer = NULL; 52 s->ringbuffer_size = 0; 53 s->new_ringbuffer_size = 0; 54 s->ringbuffer_mask = 0; 55 56 s->context_map = NULL; 57 s->context_modes = NULL; 58 s->dist_context_map = NULL; 59 s->context_map_slice = NULL; 60 s->dist_context_map_slice = NULL; 61 62 s->sub_loop_counter = 0; 63 64 s->literal_hgroup.codes = NULL; 65 s->literal_hgroup.htrees = NULL; 66 s->insert_copy_hgroup.codes = NULL; 67 s->insert_copy_hgroup.htrees = NULL; 68 s->distance_hgroup.codes = NULL; 69 s->distance_hgroup.htrees = NULL; 70 71 s->is_last_metablock = 0; 72 s->is_uncompressed = 0; 73 s->is_metadata = 0; 74 s->should_wrap_ringbuffer = 0; 75 s->canny_ringbuffer_allocation = 1; 76 77 s->window_bits = 0; 78 s->max_distance = 0; 79 s->dist_rb[0] = 16; 80 s->dist_rb[1] = 15; 81 s->dist_rb[2] = 11; 82 s->dist_rb[3] = 4; 83 s->dist_rb_idx = 0; 84 s->block_type_trees = NULL; 85 s->block_len_trees = NULL; 86 87 /* Make small negative indexes addressable. */ 88 s->symbol_lists = &s->symbols_lists_array[BROTLI_HUFFMAN_MAX_CODE_LENGTH + 1]; 89 90 s->mtf_upper_bound = 63; 91 92 s->dictionary = BrotliGetDictionary(); 93 s->transforms = BrotliGetTransforms(); 94 95 return BROTLI_TRUE; 96 } 97 98 void BrotliDecoderStateMetablockBegin(BrotliDecoderState* s) { 99 s->meta_block_remaining_len = 0; 100 s->block_length[0] = 1U << 24; 101 s->block_length[1] = 1U << 24; 102 s->block_length[2] = 1U << 24; 103 s->num_block_types[0] = 1; 104 s->num_block_types[1] = 1; 105 s->num_block_types[2] = 1; 106 s->block_type_rb[0] = 1; 107 s->block_type_rb[1] = 0; 108 s->block_type_rb[2] = 1; 109 s->block_type_rb[3] = 0; 110 s->block_type_rb[4] = 1; 111 s->block_type_rb[5] = 0; 112 s->context_map = NULL; 113 s->context_modes = NULL; 114 s->dist_context_map = NULL; 115 s->context_map_slice = NULL; 116 s->literal_htree = NULL; 117 s->dist_context_map_slice = NULL; 118 s->dist_htree_index = 0; 119 s->context_lookup = NULL; 120 s->literal_hgroup.codes = NULL; 121 s->literal_hgroup.htrees = NULL; 122 s->insert_copy_hgroup.codes = NULL; 123 s->insert_copy_hgroup.htrees = NULL; 124 s->distance_hgroup.codes = NULL; 125 s->distance_hgroup.htrees = NULL; 126 } 127 128 void BrotliDecoderStateCleanupAfterMetablock(BrotliDecoderState* s) { 129 BROTLI_DECODER_FREE(s, s->context_modes); 130 BROTLI_DECODER_FREE(s, s->context_map); 131 BROTLI_DECODER_FREE(s, s->dist_context_map); 132 BROTLI_DECODER_FREE(s, s->literal_hgroup.htrees); 133 BROTLI_DECODER_FREE(s, s->insert_copy_hgroup.htrees); 134 BROTLI_DECODER_FREE(s, s->distance_hgroup.htrees); 135 } 136 137 void BrotliDecoderStateCleanup(BrotliDecoderState* s) { 138 BrotliDecoderStateCleanupAfterMetablock(s); 139 140 BROTLI_DECODER_FREE(s, s->ringbuffer); 141 BROTLI_DECODER_FREE(s, s->block_type_trees); 142 } 143 144 BROTLI_BOOL BrotliDecoderHuffmanTreeGroupInit(BrotliDecoderState* s, 145 HuffmanTreeGroup* group, uint32_t alphabet_size, uint32_t max_symbol, 146 uint32_t ntrees) { 147 /* Pack two allocations into one */ 148 const size_t max_table_size = kMaxHuffmanTableSize[(alphabet_size + 31) >> 5]; 149 const size_t code_size = sizeof(HuffmanCode) * ntrees * max_table_size; 150 const size_t htree_size = sizeof(HuffmanCode*) * ntrees; 151 /* Pointer alignment is, hopefully, wider than sizeof(HuffmanCode). */ 152 HuffmanCode** p = (HuffmanCode**)BROTLI_DECODER_ALLOC(s, 153 code_size + htree_size); 154 group->alphabet_size = (uint16_t)alphabet_size; 155 group->max_symbol = (uint16_t)max_symbol; 156 group->num_htrees = (uint16_t)ntrees; 157 group->htrees = p; 158 group->codes = (HuffmanCode*)(&p[ntrees]); 159 return !!p; 160 } 161 162 #if defined(__cplusplus) || defined(c_plusplus) 163 } /* extern "C" */ 164 #endif 165
