ZeroTierOne/node/AtomicCounter.hpp

80 lines
1.5 KiB
C++

/*
* Copyright (c)2013-2020 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: 2024-01-01
*
* 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"
#include "TriviallyCopyable.hpp"
#ifndef __GNUC__
#include <intrin.h>
#endif
namespace ZeroTier {
/**
* Simple atomic integer used for reference and other counters
*
* @tparam T Type of underlying integer (default: int)
*/
template<typename T = int>
class AtomicCounter : public TriviallyCopyable
{
public:
ZT_ALWAYS_INLINE AtomicCounter() : _v(0) {}
explicit ZT_ALWAYS_INLINE AtomicCounter(T iv) : _v(iv) {}
ZT_ALWAYS_INLINE T load() const
{
#ifdef __GNUC__
return __sync_or_and_fetch(&_v,0);
#else
return _v.load();
#endif
}
ZT_ALWAYS_INLINE void zero() { _v = 0; }
ZT_ALWAYS_INLINE T operator++()
{
#ifdef __GNUC__
return __sync_add_and_fetch(&_v,1);
#else
return ++_v;
#endif
}
ZT_ALWAYS_INLINE T operator--()
{
#ifdef __GNUC__
return __sync_sub_and_fetch(&_v,1);
#else
return --_v;
#endif
}
private:
ZT_ALWAYS_INLINE AtomicCounter(const AtomicCounter &) {}
ZT_ALWAYS_INLINE const AtomicCounter &operator=(const AtomicCounter &) { return *this; }
#ifdef __GNUC__
T _v;
#else
typename std::atomic<T> _v;
#endif
};
} // namespace ZeroTier
#endif