ClickHouse/src/IO/BoundedReadBuffer.h

#pragma once
#include <IO/ReadBufferFromFileDecorator.h>


namespace DB
{

class BoundedReadBuffer : public ReadBufferFromFileDecorator
{
public:
    explicit BoundedReadBuffer(std::unique_ptr<SeekableReadBuffer> impl_);

    bool supportsRightBoundedReads() const override { return true; }

    void setReadUntilPosition(size_t position) override;

    void setReadUntilEnd() override;

    bool nextImpl() override;

    off_t seek(off_t off, int whence) override;

    Range getRemainingReadRange() const override;

private:
    std::optional<size_t> read_until_position;
    size_t file_offset_of_buffer_end = 0;
};

}