diff -r 000000000000 -r e4d67989cc36 ossrv_pub/boost_apis/boost/state_saver.hpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/ossrv_pub/boost_apis/boost/state_saver.hpp Tue Feb 02 02:01:42 2010 +0200 @@ -0,0 +1,94 @@ +#ifndef BOOST_STATE_SAVER_HPP +#define BOOST_STATE_SAVER_HPP + +// MS compatible compilers support #pragma once +#if defined(_MSC_VER) && (_MSC_VER >= 1020) +# pragma once +#endif + +/////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8 +// state_saver.hpp: + +// (C) Copyright 2003-4 Pavel Vozenilek and Robert Ramey - http://www.rrsd.com. +// Use, modification and distribution is subject to 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) + +// See http://www.boost.org for updates, documentation, and revision history. + +// Inspired by Daryle Walker's iostate_saver concept. This saves the original +// value of a variable when a state_saver is constructed and restores +// upon destruction. Useful for being sure that state is restored to +// variables upon exit from scope. + + +#include +#ifndef BOOST_NO_EXCEPTIONS + #include +#endif + +#include +#include +#include +#include + +#include +#include + +namespace boost { + +template +// T requirements: +// - POD or object semantic (cannot be reference, function, ...) +// - copy constructor +// - operator = (no-throw one preferred) +class state_saver : private boost::noncopyable +{ +private: + const T previous_value; + T & previous_ref; + + struct restore { + static void invoke(T & previous_ref, const T & previous_value){ + previous_ref = previous_value; // won't throw + } + }; + + struct restore_with_exception { + static void invoke(T & previous_ref, const T & previous_value){ + BOOST_TRY{ + previous_ref = previous_value; + } + BOOST_CATCH(::std::exception &) { + // we must ignore it - we are in destructor + } + BOOST_CATCH_END + } + }; + +public: + state_saver( + T & object + ) : + previous_value(object), + previous_ref(object) + {} + + ~state_saver() { + #ifndef BOOST_NO_EXCEPTIONS + typedef BOOST_DEDUCED_TYPENAME mpl::eval_if< + has_nothrow_copy, + mpl::identity, + mpl::identity + >::type typex; + typex::invoke(previous_ref, previous_value); + #else + previous_ref = previous_value; + #endif + } + +}; // state_saver<> + +} // boost + +#endif //BOOST_STATE_SAVER_HPP