Imported Upstream version 1.57.0upstream/1.57.0

1 files changed, 165 insertions, 0 deletions

diff --git a/boost/log/utility/manipulators/add_value.hpp b/boost/log/utility/manipulators/add_value.hpp
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+++ b/boost/log/utility/manipulators/add_value.hpp
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+/*
+ *          Copyright Andrey Semashev 2007 - 2014.
+ * 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)
+ */
+/*!
+ * \file   add_value.hpp
+ * \author Andrey Semashev
+ * \date   26.11.2012
+ *
+ * This header contains the \c add_value manipulator.
+ */
+
+#ifndef BOOST_LOG_UTILITY_MANIPULATORS_ADD_VALUE_HPP_INCLUDED_
+#define BOOST_LOG_UTILITY_MANIPULATORS_ADD_VALUE_HPP_INCLUDED_
+
+#include <boost/mpl/if.hpp>
+#include <boost/type_traits/is_scalar.hpp>
+#include <boost/type_traits/remove_cv.hpp>
+#include <boost/type_traits/remove_reference.hpp>
+#include <boost/log/detail/config.hpp>
+#include <boost/log/detail/embedded_string_type.hpp>
+#include <boost/log/attributes/attribute_name.hpp>
+#include <boost/log/attributes/attribute_value_impl.hpp>
+#include <boost/log/expressions/keyword_fwd.hpp>
+#include <boost/log/sources/record_ostream.hpp>
+#include <boost/log/detail/header.hpp>
+
+#ifdef BOOST_HAS_PRAGMA_ONCE
+#pragma once
+#endif
+
+#ifdef _MSC_VER
+#pragma warning(push)
+// 'boost::log::v2s_mt_nt6::add_value_manip<RefT>::m_value' : reference member is initialized to a temporary that doesn't persist after the constructor exits
+// This is intentional since the manipulator can be used with a temporary, which will be used before the streaming expression ends and it is destroyed.
+#pragma warning(disable: 4413)
+// returning address of local variable or temporary
+// This warning refers to add_value_manip<RefT>::get_value() when RefT is an rvalue reference. We store the reference in the manipulator and we intend to return it as is.
+#pragma warning(disable: 4172)
+#endif
+
+namespace boost {
+
+BOOST_LOG_OPEN_NAMESPACE
+
+//! Attribute value manipulator
+template< typename RefT >
+class add_value_manip
+{
+public:
+    //! Stored reference type
+    typedef RefT reference_type;
+    //! Attribute value type
+    typedef typename remove_cv< typename remove_reference< reference_type >::type >::type value_type;
+
+private:
+    //  The stored reference type is an lvalue reference since apparently different compilers (GCC and MSVC) have different quirks when rvalue references are stored as members.
+    //  Additionally, MSVC (at least 11.0) has a bug which causes a dangling reference to be stored in the manipulator, if a scalar rvalue is passed to the add_value generator.
+    //  To work around this problem we save the value inside the manipulator in this case.
+    typedef typename remove_reference< reference_type >::type& lvalue_reference_type;
+
+    typedef typename mpl::if_<
+        is_scalar< value_type >,
+        value_type,
+        lvalue_reference_type
+    >::type stored_type;
+
+    typedef typename mpl::if_<
+        is_scalar< value_type >,
+        value_type,
+        reference_type
+    >::type get_value_result_type;
+
+private:
+    //! Attribute value
+    stored_type m_value;
+    //! Attribute name
+    attribute_name m_name;
+
+public:
+    //! Initializing constructor
+    add_value_manip(attribute_name const& name, reference_type value) : m_value(static_cast< lvalue_reference_type >(value)), m_name(name)
+    {
+    }
+
+    //! Returns attribute name
+    attribute_name get_name() const { return m_name; }
+    //! Returns attribute value
+    get_value_result_type get_value() const { return static_cast< get_value_result_type >(m_value); }
+};
+
+//! The operator attaches an attribute value to the log record
+template< typename CharT, typename RefT >
+inline basic_record_ostream< CharT >& operator<< (basic_record_ostream< CharT >& strm, add_value_manip< RefT > const& manip)
+{
+    typedef typename aux::make_embedded_string_type< typename add_value_manip< RefT >::value_type >::type value_type;
+    attribute_value value(new attributes::attribute_value_impl< value_type >(manip.get_value()));
+    strm.get_record().attribute_values().insert(manip.get_name(), value);
+    return strm;
+}
+
+//! The function creates a manipulator that attaches an attribute value to a log record
+#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
+
+template< typename T >
+inline add_value_manip< T&& > add_value(attribute_name const& name, T&& value)
+{
+    return add_value_manip< T&& >(name, static_cast< T&& >(value));
+}
+
+//! \overload
+template< typename DescriptorT, template< typename > class ActorT >
+inline add_value_manip< typename DescriptorT::value_type&& >
+add_value(expressions::attribute_keyword< DescriptorT, ActorT > const&, typename DescriptorT::value_type&& value)
+{
+    typedef typename DescriptorT::value_type value_type;
+    return add_value_manip< value_type&& >(DescriptorT::get_name(), static_cast< value_type&& >(value));
+}
+
+//! \overload
+template< typename DescriptorT, template< typename > class ActorT >
+inline add_value_manip< typename DescriptorT::value_type& >
+add_value(expressions::attribute_keyword< DescriptorT, ActorT > const&, typename DescriptorT::value_type& value)
+{
+    return add_value_manip< typename DescriptorT::value_type& >(DescriptorT::get_name(), value);
+}
+
+//! \overload
+template< typename DescriptorT, template< typename > class ActorT >
+inline add_value_manip< typename DescriptorT::value_type const& >
+add_value(expressions::attribute_keyword< DescriptorT, ActorT > const&, typename DescriptorT::value_type const& value)
+{
+    return add_value_manip< typename DescriptorT::value_type const& >(DescriptorT::get_name(), value);
+}
+
+#else // !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
+
+template< typename T >
+inline add_value_manip< T const& > add_value(attribute_name const& name, T const& value)
+{
+    return add_value_manip< T const& >(name, value);
+}
+
+template< typename DescriptorT, template< typename > class ActorT >
+inline add_value_manip< typename DescriptorT::value_type const& >
+add_value(expressions::attribute_keyword< DescriptorT, ActorT > const&, typename DescriptorT::value_type const& value)
+{
+    return add_value_manip< typename DescriptorT::value_type const& >(DescriptorT::get_name(), value);
+}
+
+#endif // !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
+
+BOOST_LOG_CLOSE_NAMESPACE // namespace log
+
+} // namespace boost
+
+#ifdef _MSC_VER
+#pragma warning(pop)
+#endif
+
+#include <boost/log/detail/footer.hpp>
+
+#endif // BOOST_LOG_UTILITY_MANIPULATORS_ADD_VALUE_HPP_INCLUDED_