/
AtomicCounter.hpp
73 lines (61 loc) · 1.21 KB
/
AtomicCounter.hpp
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/*
* Copyright (c)2019 ZeroTier, Inc.
*
* Use of this software is governed by the Business Source License included
* in the LICENSE.TXT file in the project's root directory.
*
* Change Date: 2026-01-01
*
* On the date above, in accordance with the Business Source License, use
* of this software will be governed by version 2.0 of the Apache License.
*/
/****/
#ifndef ZT_ATOMICCOUNTER_HPP
#define ZT_ATOMICCOUNTER_HPP
#include "Constants.hpp"
#ifndef __GNUC__
#include <atomic>
#endif
namespace ZeroTier {
/**
* Simple atomic counter supporting increment and decrement
*/
class AtomicCounter
{
public:
AtomicCounter() { _v = 0; }
inline int load() const
{
#ifdef __GNUC__
return __sync_or_and_fetch(const_cast<int *>(&_v),0);
#else
return _v.load();
#endif
}
inline int operator++()
{
#ifdef __GNUC__
return __sync_add_and_fetch(&_v,1);
#else
return ++_v;
#endif
}
inline int operator--()
{
#ifdef __GNUC__
return __sync_sub_and_fetch(&_v,1);
#else
return --_v;
#endif
}
private:
AtomicCounter(const AtomicCounter &) {}
const AtomicCounter &operator=(const AtomicCounter &) { return *this; }
#ifdef __GNUC__
int _v;
#else
std::atomic_int _v;
#endif
};
} // namespace ZeroTier
#endif