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https://github.com/google/brotli.git
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11df843cf0
* pull `BROTLI_MAX_BACKWARD_LIMIT` to constants * split generic and Zopfli backward references code * pull hashers init and stitch invocation to encoder * make `dictionary_hash` a compilation unit * add `size hint` parameter * add new hasher * use `size hint` to pick new hasher for q4 * modernize clz guard (fix #495) * move `hash to binary tree` to separate file * add `Initialize` and `Cleanup` to all hashers * do not raise OOM if malloc(0) == NULL (fix #500)
54 lines
2.3 KiB
C
54 lines
2.3 KiB
C
/* Copyright 2015 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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/* Function for fast encoding of an input fragment, independently from the input
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history. This function uses two-pass processing: in the first pass we save
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the found backward matches and literal bytes into a buffer, and in the
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second pass we emit them into the bit stream using prefix codes built based
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on the actual command and literal byte histograms. */
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#ifndef BROTLI_ENC_COMPRESS_FRAGMENT_TWO_PASS_H_
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#define BROTLI_ENC_COMPRESS_FRAGMENT_TWO_PASS_H_
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#include <brotli/types.h>
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#include "./memory.h"
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#include "./port.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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static const size_t kCompressFragmentTwoPassBlockSize = 1 << 17;
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/* Compresses "input" string to the "*storage" buffer as one or more complete
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meta-blocks, and updates the "*storage_ix" bit position.
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If "is_last" is 1, emits an additional empty last meta-block.
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REQUIRES: "input_size" is greater than zero, or "is_last" is 1.
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REQUIRES: "command_buf" and "literal_buf" point to at least
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kCompressFragmentTwoPassBlockSize long arrays.
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REQUIRES: All elements in "table[0..table_size-1]" are initialized to zero.
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REQUIRES: "table_size" is a power of two
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OUTPUT: maximal copy distance <= |input_size|
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OUTPUT: maximal copy distance <= BROTLI_MAX_BACKWARD_LIMIT(18) */
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BROTLI_INTERNAL void BrotliCompressFragmentTwoPass(MemoryManager* m,
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const uint8_t* input,
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size_t input_size,
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BROTLI_BOOL is_last,
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uint32_t* command_buf,
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uint8_t* literal_buf,
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int* table,
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size_t table_size,
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size_t* storage_ix,
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uint8_t* storage);
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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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#endif /* BROTLI_ENC_COMPRESS_FRAGMENT_TWO_PASS_H_ */
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