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/*
* Copyright (c) [2012-2015] Novell, Inc.
*
* All Rights Reserved.
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of version 2 of the GNU General Public License as published
* by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, contact Novell, Inc.
*
* To contact Novell about this file by physical or electronic mail, you may
* find current contact information at www.novell.com.
*/
#ifndef SNAPPER_REF_COUNTER_H
#define SNAPPER_REF_COUNTER_H
#include <chrono>
#include <boost/thread.hpp>
#include <boost/noncopyable.hpp>
using namespace std::chrono;
class RefCounter : private boost::noncopyable
{
public:
RefCounter();
int inc_use_count();
int dec_use_count();
void update_use_time();
int use_count() const;
milliseconds unused_for() const;
private:
mutable boost::mutex mutex;
int counter = 0;
steady_clock::time_point last_used;
};
class RefHolder
{
public:
RefHolder(RefCounter& ref) : ref(ref)
{ ref.inc_use_count(); }
~RefHolder()
{ ref.dec_use_count(); }
private:
RefCounter& ref;
};
#endif
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