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
13 #include "../common/dictionary.h"
14 #include "huffman.h"
15
16 #if defined(__cplusplus) || defined(c_plusplus)
17 extern "C" {
18 #endif
19
BrotliDecoderStateInit(BrotliDecoderState * s,brotli_alloc_func alloc_func,brotli_free_func free_func,void * opaque)20 BROTLI_BOOL BrotliDecoderStateInit(BrotliDecoderState* s,
21 brotli_alloc_func alloc_func, brotli_free_func free_func, void* opaque) {
22 if (!alloc_func) {
23 s->alloc_func = BrotliDefaultAllocFunc;
24 s->free_func = BrotliDefaultFreeFunc;
25 s->memory_manager_opaque = 0;
26 } else {
27 s->alloc_func = alloc_func;
28 s->free_func = free_func;
29 s->memory_manager_opaque = opaque;
30 }
31
32 s->error_code = 0; /* BROTLI_DECODER_NO_ERROR */
33
34 BrotliInitBitReader(&s->br);
35 s->state = BROTLI_STATE_UNINITED;
36 s->large_window = 0;
37 s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_NONE;
38 s->substate_uncompressed = BROTLI_STATE_UNCOMPRESSED_NONE;
39 s->substate_decode_uint8 = BROTLI_STATE_DECODE_UINT8_NONE;
40 s->substate_read_block_length = BROTLI_STATE_READ_BLOCK_LENGTH_NONE;
41
42 s->buffer_length = 0;
43 s->loop_counter = 0;
44 s->pos = 0;
45 s->rb_roundtrips = 0;
46 s->partial_pos_out = 0;
47 s->used_input = 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->literal_hgroup.codes = NULL;
63 s->literal_hgroup.htrees = NULL;
64 s->insert_copy_hgroup.codes = NULL;
65 s->insert_copy_hgroup.htrees = NULL;
66 s->distance_hgroup.codes = NULL;
67 s->distance_hgroup.htrees = NULL;
68
69 s->is_last_metablock = 0;
70 s->is_uncompressed = 0;
71 s->is_metadata = 0;
72 s->should_wrap_ringbuffer = 0;
73 s->canny_ringbuffer_allocation = 1;
74
75 s->window_bits = 0;
76 s->max_distance = 0;
77 s->dist_rb[0] = 16;
78 s->dist_rb[1] = 15;
79 s->dist_rb[2] = 11;
80 s->dist_rb[3] = 4;
81 s->dist_rb_idx = 0;
82 s->block_type_trees = NULL;
83 s->block_len_trees = NULL;
84
85 s->mtf_upper_bound = 63;
86
87 s->compound_dictionary = NULL;
88 s->dictionary =
89 BrotliSharedDictionaryCreateInstance(alloc_func, free_func, opaque);
90 if (!s->dictionary) return BROTLI_FALSE;
91
92 s->metadata_start_func = NULL;
93 s->metadata_chunk_func = NULL;
94 s->metadata_callback_opaque = 0;
95
96 return BROTLI_TRUE;
97 }
98
BrotliDecoderStateMetablockBegin(BrotliDecoderState * s)99 void BrotliDecoderStateMetablockBegin(BrotliDecoderState* s) {
100 s->meta_block_remaining_len = 0;
101 s->block_length[0] = BROTLI_BLOCK_SIZE_CAP;
102 s->block_length[1] = BROTLI_BLOCK_SIZE_CAP;
103 s->block_length[2] = BROTLI_BLOCK_SIZE_CAP;
104 s->num_block_types[0] = 1;
105 s->num_block_types[1] = 1;
106 s->num_block_types[2] = 1;
107 s->block_type_rb[0] = 1;
108 s->block_type_rb[1] = 0;
109 s->block_type_rb[2] = 1;
110 s->block_type_rb[3] = 0;
111 s->block_type_rb[4] = 1;
112 s->block_type_rb[5] = 0;
113 s->context_map = NULL;
114 s->context_modes = NULL;
115 s->dist_context_map = NULL;
116 s->context_map_slice = NULL;
117 s->literal_htree = NULL;
118 s->dist_context_map_slice = NULL;
119 s->dist_htree_index = 0;
120 s->context_lookup = NULL;
121 s->literal_hgroup.codes = NULL;
122 s->literal_hgroup.htrees = NULL;
123 s->insert_copy_hgroup.codes = NULL;
124 s->insert_copy_hgroup.htrees = NULL;
125 s->distance_hgroup.codes = NULL;
126 s->distance_hgroup.htrees = NULL;
127 }
128
BrotliDecoderStateCleanupAfterMetablock(BrotliDecoderState * s)129 void BrotliDecoderStateCleanupAfterMetablock(BrotliDecoderState* s) {
130 BROTLI_DECODER_FREE(s, s->context_modes);
131 BROTLI_DECODER_FREE(s, s->context_map);
132 BROTLI_DECODER_FREE(s, s->dist_context_map);
133 BROTLI_DECODER_FREE(s, s->literal_hgroup.htrees);
134 BROTLI_DECODER_FREE(s, s->insert_copy_hgroup.htrees);
135 BROTLI_DECODER_FREE(s, s->distance_hgroup.htrees);
136 }
137
138 #ifdef BROTLI_REPORTING
139 /* When BROTLI_REPORTING is defined extra reporting module have to be linked. */
140 void BrotliDecoderOnFinish(const BrotliDecoderState* s);
141 #define BROTLI_DECODER_ON_FINISH(s) BrotliDecoderOnFinish(s);
142 #else
143 #if !defined(BROTLI_DECODER_ON_FINISH)
144 #define BROTLI_DECODER_ON_FINISH(s) (void)(s);
145 #endif
146 #endif
147
BrotliDecoderStateCleanup(BrotliDecoderState * s)148 void BrotliDecoderStateCleanup(BrotliDecoderState* s) {
149 BrotliDecoderStateCleanupAfterMetablock(s);
150
151 BROTLI_DECODER_ON_FINISH(s);
152
153 BROTLI_DECODER_FREE(s, s->compound_dictionary);
154 BrotliSharedDictionaryDestroyInstance(s->dictionary);
155 s->dictionary = NULL;
156 BROTLI_DECODER_FREE(s, s->ringbuffer);
157 BROTLI_DECODER_FREE(s, s->block_type_trees);
158 }
159
BrotliDecoderHuffmanTreeGroupInit(BrotliDecoderState * s,HuffmanTreeGroup * group,brotli_reg_t alphabet_size_max,brotli_reg_t alphabet_size_limit,brotli_reg_t ntrees)160 BROTLI_BOOL BrotliDecoderHuffmanTreeGroupInit(BrotliDecoderState* s,
161 HuffmanTreeGroup* group, brotli_reg_t alphabet_size_max,
162 brotli_reg_t alphabet_size_limit, brotli_reg_t ntrees) {
163 /* 376 = 256 (1-st level table) + 4 + 7 + 15 + 31 + 63 (2-nd level mix-tables)
164 This number is discovered "unlimited" "enough" calculator; it is actually
165 a wee bigger than required in several cases (especially for alphabets with
166 less than 16 symbols). */
167 const size_t max_table_size = alphabet_size_limit + 376;
168 const size_t code_size = sizeof(HuffmanCode) * ntrees * max_table_size;
169 const size_t htree_size = sizeof(HuffmanCode*) * ntrees;
170 /* Pointer alignment is, hopefully, wider than sizeof(HuffmanCode). */
171 HuffmanCode** p = (HuffmanCode**)BROTLI_DECODER_ALLOC(s,
172 code_size + htree_size);
173 group->alphabet_size_max = (uint16_t)alphabet_size_max;
174 group->alphabet_size_limit = (uint16_t)alphabet_size_limit;
175 group->num_htrees = (uint16_t)ntrees;
176 group->htrees = p;
177 group->codes = (HuffmanCode*)(&p[ntrees]);
178 return !!p;
179 }
180
181 #if defined(__cplusplus) || defined(c_plusplus)
182 } /* extern "C" */
183 #endif
184