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37 lines
983 B
C++
37 lines
983 B
C++
#pragma once
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#include <IO/ReadBuffer.h>
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namespace DB
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{
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class SeekableReadBuffer : public ReadBuffer
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{
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public:
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SeekableReadBuffer(Position ptr, size_t size)
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: ReadBuffer(ptr, size) {}
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SeekableReadBuffer(Position ptr, size_t size, size_t offset)
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: ReadBuffer(ptr, size, offset) {}
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/**
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* Shifts buffer current position to given offset.
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* @param off Offset.
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* @param whence Seek mode (@see SEEK_SET, @see SEEK_CUR).
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* @return New position from the beginning of underlying buffer / file.
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*/
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virtual off_t seek(off_t off, int whence) = 0;
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/**
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* Keep in mind that seekable buffer may encounter eof() once and the working buffer
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* may get into inconsistent state. Don't forget to reset it on the first nextImpl()
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* after seek().
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*/
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/**
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* @return Offset from the begin of the underlying buffer / file corresponds to the buffer current position.
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*/
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virtual off_t getPosition() = 0;
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};
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}
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