ClickHouse/src/IO/ReadBufferFromFileDecorator.h
2022-06-20 15:22:56 +02:00

40 lines
1.0 KiB
C++

#pragma once
#include <IO/ReadBufferFromFileBase.h>
namespace DB
{
/// Delegates all reads to underlying buffer. Doesn't have own memory.
class ReadBufferFromFileDecorator : public ReadBufferFromFileBase
{
public:
explicit ReadBufferFromFileDecorator(std::unique_ptr<SeekableReadBuffer> impl_);
ReadBufferFromFileDecorator(std::unique_ptr<SeekableReadBuffer> impl_, const String & file_name_);
std::string getFileName() const override;
off_t getPosition() override;
off_t seek(off_t off, int whence) override;
bool nextImpl() override;
bool isWithFileSize() const { return dynamic_cast<const WithFileSize *>(impl.get()) != nullptr; }
const ReadBuffer & getWrappedReadBuffer() const { return *impl; }
ReadBuffer & getWrappedReadBuffer() { return *impl; }
bool isIntegratedWithFilesystemCache() const override { return impl->isIntegratedWithFilesystemCache(); }
size_t getFileSize() override;
protected:
std::unique_ptr<SeekableReadBuffer> impl;
String file_name;
};
}