citra/src/common/lz4_compression.h
Lioncash 00213377b1 lz4_compression: Make use of std::span
Allows making the incoming data stream non-allocating.
2021-05-24 15:00:59 -04:00

61 lines
2.2 KiB
C++

// Copyright 2019 yuzu Emulator Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#pragma once
#include <span>
#include <vector>
#include "common/common_types.h"
namespace Common::Compression {
/**
* Compresses a source memory region with LZ4 and returns the compressed data in a vector.
*
* @param source The uncompressed source memory region.
* @param source_size The size of the uncompressed source memory region.
*
* @return the compressed data.
*/
[[nodiscard]] std::vector<u8> CompressDataLZ4(const u8* source, std::size_t source_size);
/**
* Utilizes the LZ4 subalgorithm LZ4HC with the specified compression level. Higher compression
* levels result in a smaller compressed size, but require more CPU time for compression. The
* compression level has almost no impact on decompression speed. Data compressed with LZ4HC can
* also be decompressed with the default LZ4 decompression.
*
* @param source The uncompressed source memory region.
* @param source_size The size of the uncompressed source memory region.
* @param compression_level The used compression level. Should be between 3 and 12.
*
* @return the compressed data.
*/
[[nodiscard]] std::vector<u8> CompressDataLZ4HC(const u8* source, std::size_t source_size,
s32 compression_level);
/**
* Utilizes the LZ4 subalgorithm LZ4HC with the highest possible compression level.
*
* @param source The uncompressed source memory region.
* @param source_size The size of the uncompressed source memory region
*
* @return the compressed data.
*/
[[nodiscard]] std::vector<u8> CompressDataLZ4HCMax(const u8* source, std::size_t source_size);
/**
* Decompresses a source memory region with LZ4 and returns the uncompressed data in a vector.
*
* @param compressed the compressed source memory region.
* @param uncompressed_size the size in bytes of the uncompressed data.
*
* @return the decompressed data.
*/
[[nodiscard]] std::vector<u8> DecompressDataLZ4(std::span<const u8> compressed,
std::size_t uncompressed_size);
} // namespace Common::Compression