dec/state.c

   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 "./huffman.h"
   8 #include "./state.h"
   9
  10 #include <stdlib.h>
  11 #include <string.h>
  12
  13 #if defined(__cplusplus) || defined(c_plusplus)
  14 extern "C" {
  15 #endif
  16
  17 static void* DefaultAllocFunc(void* opaque, size_t size) {
  18   BROTLI_UNUSED(opaque);
  19   return malloc(size);
  20 }
  21
  22 static void DefaultFreeFunc(void* opaque, void* address) {
  23   BROTLI_UNUSED(opaque);
  24   free(address);
  25 }
  26
  27 void BrotliStateInit(BrotliState* s) {
  28   BrotliStateInitWithCustomAllocators(s, 0, 0, 0);
  29 }
  30
  31 void BrotliStateInitWithCustomAllocators(BrotliState* s,
  32     brotli_alloc_func alloc_func, brotli_free_func free_func, void* opaque) {
  33   if (!alloc_func) {
  34     s->alloc_func = DefaultAllocFunc;
  35     s->free_func = DefaultFreeFunc;
  36     s->memory_manager_opaque = 0;
  37   } else {
  38     s->alloc_func = alloc_func;
  39     s->free_func = free_func;
  40     s->memory_manager_opaque = opaque;
  41   }
  42
  43   BrotliInitBitReader(&s->br);
  44   s->state = BROTLI_STATE_UNINITED;
  45   s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_NONE;
  46   s->substate_tree_group = BROTLI_STATE_TREE_GROUP_NONE;
  47   s->substate_context_map = BROTLI_STATE_CONTEXT_MAP_NONE;
  48   s->substate_uncompressed = BROTLI_STATE_UNCOMPRESSED_NONE;
  49   s->substate_huffman = BROTLI_STATE_HUFFMAN_NONE;
  50   s->substate_decode_uint8 = BROTLI_STATE_DECODE_UINT8_NONE;
  51   s->substate_read_block_length = BROTLI_STATE_READ_BLOCK_LENGTH_NONE;
  52
  53   s->buffer_length = 0;
  54   s->loop_counter = 0;
  55   s->pos = 0;
  56   s->rb_roundtrips = 0;
  57   s->partial_pos_out = 0;
  58
  59   s->block_type_trees = NULL;
  60   s->block_len_trees = NULL;
  61   s->ringbuffer = NULL;
  62
  63   s->context_map = NULL;
  64   s->context_modes = NULL;
  65   s->dist_context_map = NULL;
  66   s->context_map_slice = NULL;
  67   s->dist_context_map_slice = NULL;
  68
  69   s->sub_loop_counter = 0;
  70
  71   s->literal_hgroup.codes = NULL;
  72   s->literal_hgroup.htrees = NULL;
  73   s->insert_copy_hgroup.codes = NULL;
  74   s->insert_copy_hgroup.htrees = NULL;
  75   s->distance_hgroup.codes = NULL;
  76   s->distance_hgroup.htrees = NULL;
  77
  78
  79   s->custom_dict = NULL;
  80   s->custom_dict_size = 0;
  81
  82   s->is_last_metablock = 0;
  83   s->window_bits = 0;
  84   s->max_distance = 0;
  85   s->dist_rb[0] = 16;
  86   s->dist_rb[1] = 15;
  87   s->dist_rb[2] = 11;
  88   s->dist_rb[3] = 4;
  89   s->dist_rb_idx = 0;
  90   s->block_type_trees = NULL;
  91   s->block_len_trees = NULL;
  92
  93   /* Make small negative indexes addressable. */
  94   s->symbol_lists = &s->symbols_lists_array[BROTLI_HUFFMAN_MAX_CODE_LENGTH + 1];
  95
  96   s->mtf_upper_bound = 255;
  97
  98   s->legacy_input_buffer = 0;
  99   s->legacy_output_buffer = 0;
 100   s->legacy_input_len = 0;
 101   s->legacy_output_len = 0;
 102   s->legacy_input_pos = 0;
 103   s->legacy_output_pos = 0;
 104 }
 105
 106 void BrotliStateMetablockBegin(BrotliState* s) {
 107   s->meta_block_remaining_len = 0;
 108   s->block_length[0] = 1U << 28;
 109   s->block_length[1] = 1U << 28;
 110   s->block_length[2] = 1U << 28;
 111   s->num_block_types[0] = 1;
 112   s->num_block_types[1] = 1;
 113   s->num_block_types[2] = 1;
 114   s->block_type_rb[0] = 1;
 115   s->block_type_rb[1] = 0;
 116   s->block_type_rb[2] = 1;
 117   s->block_type_rb[3] = 0;
 118   s->block_type_rb[4] = 1;
 119   s->block_type_rb[5] = 0;
 120   s->context_map = NULL;
 121   s->context_modes = NULL;
 122   s->dist_context_map = NULL;
 123   s->context_map_slice = NULL;
 124   s->literal_htree_index = 0;
 125   s->literal_htree = NULL;
 126   s->dist_context_map_slice = NULL;
 127   s->dist_htree_index = 0;
 128   s->context_lookup1 = NULL;
 129   s->context_lookup2 = NULL;
 130   s->literal_hgroup.codes = NULL;
 131   s->literal_hgroup.htrees = NULL;
 132   s->insert_copy_hgroup.codes = NULL;
 133   s->insert_copy_hgroup.htrees = NULL;
 134   s->distance_hgroup.codes = NULL;
 135   s->distance_hgroup.htrees = NULL;
 136 }
 137
 138 void BrotliStateCleanupAfterMetablock(BrotliState* s) {
 139   BROTLI_FREE(s, s->context_modes);
 140   BROTLI_FREE(s, s->context_map);
 141   BROTLI_FREE(s, s->dist_context_map);
 142
 143   BrotliHuffmanTreeGroupRelease(s, &s->literal_hgroup);
 144   BrotliHuffmanTreeGroupRelease(s, &s->insert_copy_hgroup);
 145   BrotliHuffmanTreeGroupRelease(s, &s->distance_hgroup);
 146 }
 147
 148 void BrotliStateCleanup(BrotliState* s) {
 149   BrotliStateCleanupAfterMetablock(s);
 150
 151   BROTLI_FREE(s, s->ringbuffer);
 152   BROTLI_FREE(s, s->block_type_trees);
 153   BROTLI_FREE(s, s->legacy_input_buffer);
 154   BROTLI_FREE(s, s->legacy_output_buffer);
 155 }
 156
 157 int BrotliStateIsStreamStart(const BrotliState* s) {
 158   return (s->state == BROTLI_STATE_UNINITED &&
 159       BrotliGetAvailableBits(&s->br) == 0);
 160 }
 161
 162 int BrotliStateIsStreamEnd(const BrotliState* s) {
 163   return s->state == BROTLI_STATE_DONE;
 164 }
 165
 166 void BrotliHuffmanTreeGroupInit(BrotliState* s, HuffmanTreeGroup* group,
 167     uint32_t alphabet_size, uint32_t ntrees) {
 168   /* Pack two allocations into one */
 169   const size_t code_size =
 170       sizeof(HuffmanCode) * (size_t)(ntrees * BROTLI_HUFFMAN_MAX_TABLE_SIZE);
 171   const size_t htree_size = sizeof(HuffmanCode*) * (size_t)ntrees;
 172   char *p = (char*)BROTLI_ALLOC(s, code_size + htree_size);
 173   group->alphabet_size = (uint16_t)alphabet_size;
 174   group->num_htrees = (uint16_t)ntrees;
 175   group->codes = (HuffmanCode*)p;
 176   group->htrees = (HuffmanCode**)(p + code_size);
 177 }
 178
 179 void BrotliHuffmanTreeGroupRelease(BrotliState* s, HuffmanTreeGroup* group) {
 180   BROTLI_FREE(s, group->codes);
 181   group->htrees = NULL;
 182 }
 183
 184 #if defined(__cplusplus) || defined(c_plusplus)
 185 } /* extern "C" */
 186 #endif