diff options
Diffstat (limited to 'modules/brotli/dec/state.c')
| -rw-r--r-- | modules/brotli/dec/state.c | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/modules/brotli/dec/state.c b/modules/brotli/dec/state.c new file mode 100644 index 0000000000..f847836dda --- /dev/null +++ b/modules/brotli/dec/state.c @@ -0,0 +1,159 @@ +/* Copyright 2015 Google Inc. All Rights Reserved. + + Distributed under MIT license. + See file LICENSE for detail or copy at https://opensource.org/licenses/MIT +*/ + +#include "./state.h" + +#include <stdlib.h> /* free, malloc */ + +#include <brotli/types.h> +#include "./huffman.h" + +#if defined(__cplusplus) || defined(c_plusplus) +extern "C" { +#endif + +BROTLI_BOOL BrotliDecoderStateInit(BrotliDecoderState* s, + brotli_alloc_func alloc_func, brotli_free_func free_func, void* opaque) { + if (!alloc_func) { + s->alloc_func = BrotliDefaultAllocFunc; + s->free_func = BrotliDefaultFreeFunc; + s->memory_manager_opaque = 0; + } else { + s->alloc_func = alloc_func; + s->free_func = free_func; + s->memory_manager_opaque = opaque; + } + + s->error_code = 0; /* BROTLI_DECODER_NO_ERROR */ + + BrotliInitBitReader(&s->br); + s->state = BROTLI_STATE_UNINITED; + s->large_window = 0; + s->substate_metablock_header = BROTLI_STATE_METABLOCK_HEADER_NONE; + s->substate_uncompressed = BROTLI_STATE_UNCOMPRESSED_NONE; + s->substate_decode_uint8 = BROTLI_STATE_DECODE_UINT8_NONE; + s->substate_read_block_length = BROTLI_STATE_READ_BLOCK_LENGTH_NONE; + + s->buffer_length = 0; + s->loop_counter = 0; + s->pos = 0; + s->rb_roundtrips = 0; + s->partial_pos_out = 0; + + s->block_type_trees = NULL; + s->block_len_trees = NULL; + s->ringbuffer = NULL; + s->ringbuffer_size = 0; + s->new_ringbuffer_size = 0; + s->ringbuffer_mask = 0; + + s->context_map = NULL; + s->context_modes = NULL; + s->dist_context_map = NULL; + s->context_map_slice = NULL; + s->dist_context_map_slice = NULL; + + s->literal_hgroup.codes = NULL; + s->literal_hgroup.htrees = NULL; + s->insert_copy_hgroup.codes = NULL; + s->insert_copy_hgroup.htrees = NULL; + s->distance_hgroup.codes = NULL; + s->distance_hgroup.htrees = NULL; + + s->is_last_metablock = 0; + s->is_uncompressed = 0; + s->is_metadata = 0; + s->should_wrap_ringbuffer = 0; + s->canny_ringbuffer_allocation = 1; + + s->window_bits = 0; + s->max_distance = 0; + s->dist_rb[0] = 16; + s->dist_rb[1] = 15; + s->dist_rb[2] = 11; + s->dist_rb[3] = 4; + s->dist_rb_idx = 0; + s->block_type_trees = NULL; + s->block_len_trees = NULL; + + s->mtf_upper_bound = 63; + + s->dictionary = BrotliGetDictionary(); + s->transforms = BrotliGetTransforms(); + + return BROTLI_TRUE; +} + +void BrotliDecoderStateMetablockBegin(BrotliDecoderState* s) { + s->meta_block_remaining_len = 0; + s->block_length[0] = 1U << 24; + s->block_length[1] = 1U << 24; + s->block_length[2] = 1U << 24; + s->num_block_types[0] = 1; + s->num_block_types[1] = 1; + s->num_block_types[2] = 1; + s->block_type_rb[0] = 1; + s->block_type_rb[1] = 0; + s->block_type_rb[2] = 1; + s->block_type_rb[3] = 0; + s->block_type_rb[4] = 1; + s->block_type_rb[5] = 0; + s->context_map = NULL; + s->context_modes = NULL; + s->dist_context_map = NULL; + s->context_map_slice = NULL; + s->literal_htree = NULL; + s->dist_context_map_slice = NULL; + s->dist_htree_index = 0; + s->context_lookup = NULL; + s->literal_hgroup.codes = NULL; + s->literal_hgroup.htrees = NULL; + s->insert_copy_hgroup.codes = NULL; + s->insert_copy_hgroup.htrees = NULL; + s->distance_hgroup.codes = NULL; + s->distance_hgroup.htrees = NULL; +} + +void BrotliDecoderStateCleanupAfterMetablock(BrotliDecoderState* s) { + BROTLI_DECODER_FREE(s, s->context_modes); + BROTLI_DECODER_FREE(s, s->context_map); + BROTLI_DECODER_FREE(s, s->dist_context_map); + BROTLI_DECODER_FREE(s, s->literal_hgroup.htrees); + BROTLI_DECODER_FREE(s, s->insert_copy_hgroup.htrees); + BROTLI_DECODER_FREE(s, s->distance_hgroup.htrees); +} + +void BrotliDecoderStateCleanup(BrotliDecoderState* s) { + BrotliDecoderStateCleanupAfterMetablock(s); + + BROTLI_DECODER_FREE(s, s->ringbuffer); + BROTLI_DECODER_FREE(s, s->block_type_trees); +} + +BROTLI_BOOL BrotliDecoderHuffmanTreeGroupInit(BrotliDecoderState* s, + HuffmanTreeGroup* group, uint32_t alphabet_size_max, + uint32_t alphabet_size_limit, uint32_t ntrees) { + /* 376 = 256 (1-st level table) + 4 + 7 + 15 + 31 + 63 (2-nd level mix-tables) + This number is discovered "unlimited" "enough" calculator; it is actually + a wee bigger than required in several cases (especially for alphabets with + less than 16 symbols). */ + const size_t max_table_size = alphabet_size_limit + 376; + const size_t code_size = sizeof(HuffmanCode) * ntrees * max_table_size; + const size_t htree_size = sizeof(HuffmanCode*) * ntrees; + /* Pointer alignment is, hopefully, wider than sizeof(HuffmanCode). */ + HuffmanCode** p = (HuffmanCode**)BROTLI_DECODER_ALLOC(s, + code_size + htree_size); + group->alphabet_size_max = (uint16_t)alphabet_size_max; + group->alphabet_size_limit = (uint16_t)alphabet_size_limit; + group->num_htrees = (uint16_t)ntrees; + group->htrees = p; + group->codes = (HuffmanCode*)(&p[ntrees]); + return !!p; +} + +#if defined(__cplusplus) || defined(c_plusplus) +} /* extern "C" */ +#endif |