cppdb/atomic_counter.h

//                                                                             
//  Copyright (C) 2010-2011  Artyom Beilis (Tonkikh) <artyomtnk@yahoo.com>     
//                                                                             
//  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)
//
//  or (at your opinion) under:
//
//                               The MIT License
//                 (See accompanying file MIT.txt or a copy at
//              http://www.opensource.org/licenses/mit-license.php)
//
#ifndef CPPDB_ATOMIC_COUNT_H
#define CPPDB_ATOMIC_COUNT_H

#include <cppdb/defs.h>


namespace cppdb {


        class CPPDB_API atomic_counter {
        public:
                explicit atomic_counter( long v);
                ~atomic_counter();

                long operator++()
                {
                        return inc();
                }
                long operator--()
                {
                        return dec();
                }
                operator long() const 
                {
                        return get();
                }
        private:
                long inc();
                long dec();
                long get() const;

                atomic_counter(atomic_counter const &);
                atomic_counter & operator=(atomic_counter const &);

                mutable union {
                        int i;
                        unsigned ui;
                        long l;
                        unsigned long ul;
                        long long ll;
                        unsigned long long ull;
                } value_;
                // Is actually used for platforms without lock
                // it would not be used when atomic operations
                // available
                void *mutex_;
        };

} // cppdb

#endif