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Diffstat (limited to 'src/third_party/boost-1.69.0/boost/smart_ptr/detail/atomic_count_pt.hpp')
-rw-r--r-- | src/third_party/boost-1.69.0/boost/smart_ptr/detail/atomic_count_pt.hpp | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/src/third_party/boost-1.69.0/boost/smart_ptr/detail/atomic_count_pt.hpp b/src/third_party/boost-1.69.0/boost/smart_ptr/detail/atomic_count_pt.hpp new file mode 100644 index 00000000000..f99b9108e3f --- /dev/null +++ b/src/third_party/boost-1.69.0/boost/smart_ptr/detail/atomic_count_pt.hpp @@ -0,0 +1,97 @@ +#ifndef BOOST_SMART_PTR_DETAIL_ATOMIC_COUNT_PTHREADS_HPP_INCLUDED +#define BOOST_SMART_PTR_DETAIL_ATOMIC_COUNT_PTHREADS_HPP_INCLUDED + +// +// boost/detail/atomic_count_pthreads.hpp +// +// Copyright (c) 2001, 2002 Peter Dimov and Multi Media Ltd. +// +// 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) +// + +#include <boost/assert.hpp> +#include <pthread.h> + +// +// The generic pthread_mutex-based implementation sometimes leads to +// inefficiencies. Example: a class with two atomic_count members +// can get away with a single mutex. +// +// Users can detect this situation by checking BOOST_AC_USE_PTHREADS. +// + +namespace boost +{ + +namespace detail +{ + +class atomic_count +{ +private: + + class scoped_lock + { + public: + + scoped_lock(pthread_mutex_t & m): m_(m) + { + BOOST_VERIFY( pthread_mutex_lock( &m_ ) == 0 ); + } + + ~scoped_lock() + { + BOOST_VERIFY( pthread_mutex_unlock( &m_ ) == 0 ); + } + + private: + + pthread_mutex_t & m_; + }; + +public: + + explicit atomic_count(long v): value_(v) + { + BOOST_VERIFY( pthread_mutex_init( &mutex_, 0 ) == 0 ); + } + + ~atomic_count() + { + BOOST_VERIFY( pthread_mutex_destroy( &mutex_ ) == 0 ); + } + + long operator++() + { + scoped_lock lock(mutex_); + return ++value_; + } + + long operator--() + { + scoped_lock lock(mutex_); + return --value_; + } + + operator long() const + { + scoped_lock lock(mutex_); + return value_; + } + +private: + + atomic_count(atomic_count const &); + atomic_count & operator=(atomic_count const &); + + mutable pthread_mutex_t mutex_; + long value_; +}; + +} // namespace detail + +} // namespace boost + +#endif // #ifndef BOOST_SMART_PTR_DETAIL_ATOMIC_COUNT_PTHREADS_HPP_INCLUDED |