forked from mirror/brotli
105 lines
3.1 KiB
Go
105 lines
3.1 KiB
Go
package brotli
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/* NOTE: this hasher does not search in the dictionary. It is used as
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backup-hasher, the main hasher already searches in it. */
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/* NOLINT(build/header_guard) */
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/* Copyright 2018 Google Inc. All Rights Reserved.
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Distributed under MIT license.
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See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
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*/
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/* Composite hasher: This hasher allows to combine two other hashers, HASHER_A
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and HASHER_B. */
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func (h *H35) HashTypeLength() uint {
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var a uint = h.ha.HashTypeLength()
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var b uint = h.hb.HashTypeLength()
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if a > b {
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return a
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} else {
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return b
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}
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}
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func (h *H35) StoreLookahead() uint {
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var a uint = h.ha.StoreLookahead()
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var b uint = h.hb.StoreLookahead()
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if a > b {
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return a
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} else {
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return b
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}
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}
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type H35 struct {
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HasherCommon
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ha HasherHandle
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hb HasherHandle
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params *BrotliEncoderParams
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}
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func SelfH35(handle HasherHandle) *H35 {
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return handle.(*H35)
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}
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func (h *H35) Initialize(params *BrotliEncoderParams) {
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h.ha = nil
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h.hb = nil
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h.params = params
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}
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/* TODO: Initialize of the hashers is defered to Prepare (and params
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remembered here) because we don't get the one_shot and input_size params
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here that are needed to know the memory size of them. Instead provide
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those params to all hashers InitializeH35 */
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func (h *H35) Prepare(one_shot bool, input_size uint, data []byte) {
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if h.ha == nil {
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var common_a *HasherCommon
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var common_b *HasherCommon
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h.ha = new(H3)
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common_a = h.ha.Common()
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common_a.params = h.params.hasher
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common_a.is_prepared_ = false
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common_a.dict_num_lookups = 0
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common_a.dict_num_matches = 0
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h.ha.Initialize(h.params)
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h.hb = new(HROLLING_FAST)
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common_b = h.hb.Common()
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common_b.params = h.params.hasher
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common_b.is_prepared_ = false
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common_b.dict_num_lookups = 0
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common_b.dict_num_matches = 0
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h.hb.Initialize(h.params)
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}
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h.ha.Prepare(one_shot, input_size, data)
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h.hb.Prepare(one_shot, input_size, data)
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}
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func (h *H35) Store(data []byte, mask uint, ix uint) {
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h.ha.Store(data, mask, ix)
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h.hb.Store(data, mask, ix)
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}
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func (h *H35) StoreRange(data []byte, mask uint, ix_start uint, ix_end uint) {
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h.ha.StoreRange(data, mask, ix_start, ix_end)
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h.hb.StoreRange(data, mask, ix_start, ix_end)
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}
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func (h *H35) StitchToPreviousBlock(num_bytes uint, position uint, ringbuffer []byte, ring_buffer_mask uint) {
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h.ha.StitchToPreviousBlock(num_bytes, position, ringbuffer, ring_buffer_mask)
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h.hb.StitchToPreviousBlock(num_bytes, position, ringbuffer, ring_buffer_mask)
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}
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func (h *H35) PrepareDistanceCache(distance_cache []int) {
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h.ha.PrepareDistanceCache(distance_cache)
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h.hb.PrepareDistanceCache(distance_cache)
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}
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func (h *H35) FindLongestMatch(dictionary *BrotliEncoderDictionary, data []byte, ring_buffer_mask uint, distance_cache []int, cur_ix uint, max_length uint, max_backward uint, gap uint, max_distance uint, out *HasherSearchResult) {
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h.ha.FindLongestMatch(dictionary, data, ring_buffer_mask, distance_cache, cur_ix, max_length, max_backward, gap, max_distance, out)
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h.hb.FindLongestMatch(dictionary, data, ring_buffer_mask, distance_cache, cur_ix, max_length, max_backward, gap, max_distance, out)
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}
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