ClickHouse/dbms/src/Compression/CompressionCodecLZ4.h

#pragma once

#include <IO/WriteBuffer.h>
#include <Compression/ICompressionCodec.h>
#include <IO/BufferWithOwnMemory.h>
#include <Parsers/StringRange.h>
#include <Compression/LZ4_decompress_faster.h>

namespace DB
{

class CompressionCodecLZ4 : public ICompressionCodec
{
public:
    UInt8 getMethodByte() const override;

    String getCodecDesc() const override;

    UInt32 getAdditionalSizeAtTheEndOfBuffer() const override { return LZ4::ADDITIONAL_BYTES_AT_END_OF_BUFFER; }

protected:
    UInt32 doCompressData(const char * source, UInt32 source_size, char * dest) const override;

private:
    void doDecompressData(const char * source, UInt32 source_size, char * dest, UInt32 uncompressed_size) const override;

    UInt32 getMaxCompressedDataSize(UInt32 uncompressed_size) const override;

    mutable LZ4::PerformanceStatistics lz4_stat;
};

class CompressionCodecLZ4HC : public CompressionCodecLZ4
{
public:

    CompressionCodecLZ4HC(int level_);

    String getCodecDesc() const override;

protected:
    UInt32 doCompressData(const char * source, UInt32 source_size, char * dest) const override;

private:
    const int level;
};

}