mirror of
https://github.com/google/brotli.git
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0454ab4ec0
This commit contains a batch of changes that were made to the Brotli
compression algorithm in the last month. Most important changes:
* Fixes to the spec.
* Change of code length code order.
* Use a 2-level Huffman lookup table in the decoder.
* Faster uncompressed meta-block decoding.
* Optimized encoding of the Huffman code.
* Detection of UTF-8 input encoding.
* UTF-8 based literal cost modeling for improved
backward reference selection.
51 lines
1.3 KiB
C
51 lines
1.3 KiB
C
/* Copyright 2013 Google Inc. All Rights Reserved.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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Bit reading helpers
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*/
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#include <assert.h>
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#include <stdlib.h>
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#include "./bit_reader.h"
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#if defined(__cplusplus) || defined(c_plusplus)
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extern "C" {
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#endif
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int BrotliInitBitReader(BrotliBitReader* const br, BrotliInput input) {
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size_t i;
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assert(br != NULL);
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br->buf_ptr_ = br->buf_;
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br->input_ = input;
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br->val_ = 0;
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br->pos_ = 0;
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br->bit_pos_ = 0;
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br->bit_end_pos_ = 0;
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br->eos_ = 0;
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if (!BrotliReadMoreInput(br)) {
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return 0;
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}
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for (i = 0; i < sizeof(br->val_); ++i) {
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br->val_ |= ((uint64_t)br->buf_[br->pos_]) << (8 * i);
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++br->pos_;
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}
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return (br->bit_end_pos_ > 0);
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}
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#if defined(__cplusplus) || defined(c_plusplus)
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} /* extern "C" */
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#endif
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