ZeroTierOne/node/AtomicCounter.hpp

114 lines
3.0 KiB
C++

/*
* ZeroTier One - Global Peer to Peer Ethernet
* Copyright (C) 2012-2013 ZeroTier Networks LLC
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* 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, see <http://www.gnu.org/licenses/>.
*
* --
*
* ZeroTier may be used and distributed under the terms of the GPLv3, which
* are available at: http://www.gnu.org/licenses/gpl-3.0.html
*
* If you would like to embed ZeroTier into a commercial application or
* redistribute it in a modified binary form, please contact ZeroTier Networks
* LLC. Start here: http://www.zerotier.com/
*/
#ifndef _ZT_ATOMICCOUNTER_HPP
#define _ZT_ATOMICCOUNTER_HPP
#include "Mutex.hpp"
#include "NonCopyable.hpp"
namespace ZeroTier {
/**
* Simple atomic counter supporting increment and decrement
*/
class AtomicCounter : NonCopyable
{
public:
/**
* Initialize counter at zero
*/
AtomicCounter()
throw() :
_v(0)
{
}
inline int operator*() const
throw()
{
#ifdef __GNUC__
return __sync_or_and_fetch(const_cast <int *> (&_v),0);
#else
_l.lock();
int v = _v;
_l.unlock();
return v;
#endif
}
inline int operator++()
throw()
{
#ifdef __GNUC__
return __sync_add_and_fetch(&_v,1);
#else
_l.lock();
int v = ++_v;
_l.unlock();
return v;
#endif
}
inline int operator--()
throw()
{
#ifdef __GNUC__
return __sync_sub_and_fetch(&_v,1);
#else
_l.lock();
int v = --_v;
_l.unlock();
return v;
#endif
}
inline bool operator==(const AtomicCounter &i) const throw() { return (**this == *i); }
inline bool operator!=(const AtomicCounter &i) const throw() { return (**this != *i); }
inline bool operator>(const AtomicCounter &i) const throw() { return (**this > *i); }
inline bool operator<(const AtomicCounter &i) const throw() { return (**this < *i); }
inline bool operator>=(const AtomicCounter &i) const throw() { return (**this >= *i); }
inline bool operator<=(const AtomicCounter &i) const throw() { return (**this <= *i); }
inline bool operator==(const int i) const throw() { return (**this == i); }
inline bool operator!=(const int i) const throw() { return (**this != i); }
inline bool operator>(const int i) const throw() { return (**this > i); }
inline bool operator<(const int i) const throw() { return (**this < i); }
inline bool operator>=(const int i) const throw() { return (**this >= i); }
inline bool operator<=(const int i) const throw() { return (**this <= i); }
private:
int _v;
#ifndef __GNUC__
Mutex _l;
#endif
};
} // namespace ZeroTier
#endif