ClickHouse/dbms/include/DB/IO/WriteBufferFromFileBase.h
2016-06-07 11:23:15 +03:00

31 lines
681 B
C++

#pragma once
#include <string>
#include <fcntl.h>
#include <DB/IO/WriteBuffer.h>
#include <DB/IO/BufferWithOwnMemory.h>
namespace DB
{
class WriteBufferFromFileBase : public BufferWithOwnMemory<WriteBuffer>
{
public:
WriteBufferFromFileBase(size_t buf_size, char * existing_memory, size_t alignment);
virtual ~WriteBufferFromFileBase();
off_t seek(off_t off, int whence = SEEK_SET);
void truncate(off_t length = 0);
virtual off_t getPositionInFile() = 0;
virtual void sync() = 0;
virtual std::string getFileName() const = 0;
virtual int getFD() const = 0;
protected:
virtual off_t doSeek(off_t off, int whence) = 0;
virtual void doTruncate(off_t length) = 0;
};
}