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34 lines
634 B
C++
34 lines
634 B
C++
#pragma once
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#include <DB/IO/ReadBuffer.h>
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namespace DB
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{
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/** Позволяет считать из другого ReadBuffer не более указанного количества байт.
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*/
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class LimitReadBuffer : public ReadBuffer
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{
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private:
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ReadBuffer & in;
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size_t limit;
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bool nextImpl() override
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{
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if (count() >= limit || !in.next())
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return false;
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working_buffer = in.buffer();
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if (limit - count() < working_buffer.size())
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working_buffer.resize(limit - count());
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return true;
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}
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public:
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LimitReadBuffer(ReadBuffer & in_, size_t limit_) : ReadBuffer(nullptr, 0), in(in_), limit(limit_) {}
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};
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}
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