38 lines
		
	
	
	
		
			725 B
		
	
	
	
		
			C++
		
	
	
	
	
	
			
		
		
	
	
			38 lines
		
	
	
	
		
			725 B
		
	
	
	
		
			C++
		
	
	
	
	
	
/*
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This file is part of Telegram Desktop,
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the official desktop application for the Telegram messaging service.
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For license and copyright information please follow this link:
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https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
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*/
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#pragma once
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#include "base/basic_types.h"
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#include <QtCore/QFile>
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namespace Storage {
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class FileLock {
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public:
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	FileLock();
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	bool lock(QFile &file, QIODevice::OpenMode mode);
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	void unlock();
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	static constexpr auto kSkipBytes = size_type(4);
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	~FileLock();
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private:
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	class Lock;
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	struct Descriptor;
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	struct LockingPid;
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	static constexpr auto kLockOffset = index_type(0);
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	static constexpr auto kLockLimit = kSkipBytes;
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	std::unique_ptr<Lock> _lock;
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};
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} // namespace Storage
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