suyu/src/common/lz4_compression.h
Lioncash df72480395 common: Make use of [[nodiscard]] where applicable
Now that clang-format makes [[nodiscard]] attributes format sensibly, we
can apply them to several functions within the common library to allow
the compiler to complain about any misuses of the functions.
2020-08-15 17:17:52 -04:00

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// 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.
*
* @return the compressed data.
*/
[[nodiscard]] std::vector<u8> CompressDataLZ4(std::span<const u8> source);
/**
* 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 compression_level the used compression level. Should be between 3 and 12.
*
* @return the compressed data.
*/
[[nodiscard]] std::vector<u8> CompressDataLZ4HC(std::span<const u8> source, s32 compression_level);
/**
* Utilizes the LZ4 subalgorithm LZ4HC with the highest possible compression level.
*
* @param source the uncompressed source memory region.
*
* @return the compressed data.
*/
[[nodiscard]] std::vector<u8> CompressDataLZ4HCMax(std::span<const u8> source);
/**
* 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(const std::vector<u8>& compressed,
std::size_t uncompressed_size);
} // namespace Common::Compression