ClickHouse/src/IO/SnappyWriteBuffer.h

#pragma once

#include "config.h"

#if USE_SNAPPY
#include <IO/BufferWithOwnMemory.h>
#include <IO/WriteBuffer.h>

namespace DB
{
/// Performs compression using snappy library and write compressed data to the underlying buffer.
class SnappyWriteBuffer : public BufferWithOwnMemory<WriteBuffer>
{
public:
    explicit SnappyWriteBuffer(
        std::unique_ptr<WriteBuffer> out_,
        size_t buf_size = DBMS_DEFAULT_BUFFER_SIZE,
        char * existing_memory = nullptr,
        size_t alignment = 0);

    explicit SnappyWriteBuffer(
        WriteBuffer & out_,
        size_t buf_size = DBMS_DEFAULT_BUFFER_SIZE,
        char * existing_memory = nullptr,
        size_t alignment = 0);

    ~SnappyWriteBuffer() override;

    void finalizeImpl() override { finish(); }

private:
    void nextImpl() override;

    void finishImpl();
    void finish();

    WriteBuffer * out;
    std::unique_ptr<WriteBuffer> out_holder;

    bool finished = false;

    String uncompress_buffer;
    String compress_buffer;
};

}

#endif