Chris@102: #ifndef BOOST_SMART_PTR_DETAIL_ATOMIC_COUNT_PTHREADS_HPP_INCLUDED
Chris@102: #define BOOST_SMART_PTR_DETAIL_ATOMIC_COUNT_PTHREADS_HPP_INCLUDED
Chris@102: 
Chris@102: //
Chris@102: //  boost/detail/atomic_count_pthreads.hpp
Chris@102: //
Chris@102: //  Copyright (c) 2001, 2002 Peter Dimov and Multi Media Ltd.
Chris@102: //
Chris@102: // Distributed under the Boost Software License, Version 1.0. (See
Chris@102: // accompanying file LICENSE_1_0.txt or copy at
Chris@102: // http://www.boost.org/LICENSE_1_0.txt)
Chris@102: //
Chris@102: 
Chris@102: #include <boost/assert.hpp>
Chris@102: #include <pthread.h>
Chris@102: 
Chris@102: //
Chris@102: //  The generic pthread_mutex-based implementation sometimes leads to
Chris@102: //    inefficiencies. Example: a class with two atomic_count members
Chris@102: //    can get away with a single mutex.
Chris@102: //
Chris@102: //  Users can detect this situation by checking BOOST_AC_USE_PTHREADS.
Chris@102: //
Chris@102: 
Chris@102: namespace boost
Chris@102: {
Chris@102: 
Chris@102: namespace detail
Chris@102: {
Chris@102: 
Chris@102: class atomic_count
Chris@102: {
Chris@102: private:
Chris@102: 
Chris@102:     class scoped_lock
Chris@102:     {
Chris@102:     public:
Chris@102: 
Chris@102:         scoped_lock(pthread_mutex_t & m): m_(m)
Chris@102:         {
Chris@102:             BOOST_VERIFY( pthread_mutex_lock( &m_ ) == 0 );
Chris@102:         }
Chris@102: 
Chris@102:         ~scoped_lock()
Chris@102:         {
Chris@102:             BOOST_VERIFY( pthread_mutex_unlock( &m_ ) == 0 );
Chris@102:         }
Chris@102: 
Chris@102:     private:
Chris@102: 
Chris@102:         pthread_mutex_t & m_;
Chris@102:     };
Chris@102: 
Chris@102: public:
Chris@102: 
Chris@102:     explicit atomic_count(long v): value_(v)
Chris@102:     {
Chris@102:         BOOST_VERIFY( pthread_mutex_init( &mutex_, 0 ) == 0 );
Chris@102:     }
Chris@102: 
Chris@102:     ~atomic_count()
Chris@102:     {
Chris@102:         BOOST_VERIFY( pthread_mutex_destroy( &mutex_ ) == 0 );
Chris@102:     }
Chris@102: 
Chris@102:     long operator++()
Chris@102:     {
Chris@102:         scoped_lock lock(mutex_);
Chris@102:         return ++value_;
Chris@102:     }
Chris@102: 
Chris@102:     long operator--()
Chris@102:     {
Chris@102:         scoped_lock lock(mutex_);
Chris@102:         return --value_;
Chris@102:     }
Chris@102: 
Chris@102:     operator long() const
Chris@102:     {
Chris@102:         scoped_lock lock(mutex_);
Chris@102:         return value_;
Chris@102:     }
Chris@102: 
Chris@102: private:
Chris@102: 
Chris@102:     atomic_count(atomic_count const &);
Chris@102:     atomic_count & operator=(atomic_count const &);
Chris@102: 
Chris@102:     mutable pthread_mutex_t mutex_;
Chris@102:     long value_;
Chris@102: };
Chris@102: 
Chris@102: } // namespace detail
Chris@102: 
Chris@102: } // namespace boost
Chris@102: 
Chris@102: #endif // #ifndef BOOST_SMART_PTR_DETAIL_ATOMIC_COUNT_PTHREADS_HPP_INCLUDED