boost/smart_ptr/detail/atomic_count_sync.hpp

#ifndef BOOST_SMART_PTR_DETAIL_ATOMIC_COUNT_SYNC_HPP_INCLUDED
#define BOOST_SMART_PTR_DETAIL_ATOMIC_COUNT_SYNC_HPP_INCLUDED
//
//  boost/detail/atomic_count_sync.hpp
//
//  atomic_count for g++ 4.1+
//
//  http://gcc.gnu.org/onlinedocs/gcc-4.1.1/gcc/Atomic-Builtins.html
//
//  Copyright 2007 Peter Dimov
//
//  Distributed under the Boost Software License, Version 1.0. (See
//  accompanying file LICENSE_1_0.txt or copy at
//  http://www.boost.org/LICENSE_1_0.txt)
//
#if defined( __ia64__ ) && defined( __INTEL_COMPILER )
# include <ia64intrin.h>
#endif
namespace boost
{
namespace detail
{
class atomic_count
{
public:
    explicit atomic_count( long v ) : value_( v ) {}
    long operator++()
    {
        return __sync_add_and_fetch( &value_, 1 );
    }
    long operator--()
    {
        return __sync_add_and_fetch( &value_, -1 );
    }
    operator long() const
    {
        return __sync_fetch_and_add( &value_, 0 );
    }
private:
    atomic_count(atomic_count const &);
    atomic_count & operator=(atomic_count const &);
    mutable long value_;
};
} // namespace detail
} // namespace boost
#endif // #ifndef BOOST_SMART_PTR_DETAIL_ATOMIC_COUNT_SYNC_HPP_INCLUDED