forked from mirrors/gecko-dev
265e672179
# ignore-this-changeset --HG-- extra : amend_source : 4d301d3b0b8711c4692392aa76088ba7fd7d1022
66 lines
2.5 KiB
C++
66 lines
2.5 KiB
C++
/* This Source Code Form is subject to the terms of the Mozilla Public
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* License, v. 2.0. If a copy of the MPL was not distributed with this
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* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
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#include "mozilla/Compression.h"
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/**
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* LZ4 is a very fast byte-wise compression algorithm.
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*
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* Compared to Google's Snappy it is faster to compress and decompress and
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* generally produces output of about the same size.
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*
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* Compared to zlib it compresses at about 10x the speed, decompresses at about
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* 4x the speed and produces output of about 1.5x the size.
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*
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*/
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using namespace mozilla::Compression;
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/**
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* Compresses 'inputSize' bytes from 'source' into 'dest'.
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* Destination buffer must be already allocated,
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* and must be sized to handle worst cases situations (input data not
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* compressible) Worst case size evaluation is provided by function
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* LZ4_compressBound()
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*
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* @param inputSize is the input size. Max supported value is ~1.9GB
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* @param return the number of bytes written in buffer dest
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*/
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extern "C" MOZ_EXPORT size_t workerlz4_compress(const char* source,
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size_t inputSize, char* dest) {
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return LZ4::compress(source, inputSize, dest);
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}
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/**
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* If the source stream is malformed, the function will stop decoding
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* and return a negative result, indicating the byte position of the
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* faulty instruction
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*
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* This function never writes outside of provided buffers, and never
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* modifies input buffer.
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*
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* note : destination buffer must be already allocated.
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* its size must be a minimum of 'outputSize' bytes.
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* @param outputSize is the output size, therefore the original size
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* @return true/false
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*/
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extern "C" MOZ_EXPORT int workerlz4_decompress(const char* source,
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size_t inputSize, char* dest,
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size_t maxOutputSize,
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size_t* bytesOutput) {
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return LZ4::decompress(source, inputSize, dest, maxOutputSize, bytesOutput);
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}
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/*
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Provides the maximum size that LZ4 may output in a "worst case"
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scenario (input data not compressible) primarily useful for memory
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allocation of output buffer.
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note : this function is limited by "int" range (2^31-1)
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@param inputSize is the input size. Max supported value is ~1.9GB
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@return maximum output size in a "worst case" scenario
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*/
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extern "C" MOZ_EXPORT size_t workerlz4_maxCompressedSize(size_t inputSize) {
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return LZ4::maxCompressedSize(inputSize);
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}
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