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38 lines
686 B
C++
38 lines
686 B
C++
#pragma once
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#include <Common/CurrentMetrics.h>
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#include <IO/MMapReadBufferFromFileDescriptor.h>
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namespace CurrentMetrics
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{
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extern const Metric OpenFileForRead;
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}
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namespace DB
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{
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class MMapReadBufferFromFile : public MMapReadBufferFromFileDescriptor
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{
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public:
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MMapReadBufferFromFile(const std::string & file_name, size_t offset, size_t length);
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/// Map till end of file.
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MMapReadBufferFromFile(const std::string & file_name, size_t offset);
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~MMapReadBufferFromFile() override;
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void close();
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private:
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int fd = -1;
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CurrentMetrics::Increment metric_increment{CurrentMetrics::OpenFileForRead};
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void open(const std::string & file_name);
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};
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}
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