--- /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 <boost/config.hpp>
+#ifndef BOOST_NO_EXCEPTIONS
+    #include <exception>
+#endif
+
+#include <boost/call_traits.hpp>
+#include <boost/noncopyable.hpp>
+#include <boost/type_traits/has_nothrow_copy.hpp>
+#include <boost/detail/no_exceptions_support.hpp>
+
+#include <boost/mpl/eval_if.hpp>
+#include <boost/mpl/identity.hpp>
+
+namespace boost {
+
+template<class T>
+// 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<T>,
+                mpl::identity<restore>,
+                mpl::identity<restore_with_exception>
+            >::type typex;
+            typex::invoke(previous_ref, previous_value);
+        #else
+            previous_ref = previous_value;
+        #endif
+    }
+
+}; // state_saver<>
+
+} // boost
+
+#endif //BOOST_STATE_SAVER_HPP