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
BrotliDecoderStateInit(BrotliDecoderState * s,brotli_alloc_func alloc_func,brotli_free_func free_func,void * opaque)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
BrotliDecoderStateMetablockBegin(BrotliDecoderState * s)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
BrotliDecoderStateCleanupAfterMetablock(BrotliDecoderState * s)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
BrotliDecoderStateCleanup(BrotliDecoderState * s)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
BrotliDecoderHuffmanTreeGroupInit(BrotliDecoderState * s,HuffmanTreeGroup * group,uint32_t alphabet_size,uint32_t max_symbol,uint32_t ntrees)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