Chris@16: /*
Chris@101:  *          Copyright Andrey Semashev 2007 - 2015.
Chris@16:  * Distributed under the Boost Software License, Version 1.0.
Chris@16:  *    (See accompanying file LICENSE_1_0.txt or copy at
Chris@16:  *          http://www.boost.org/LICENSE_1_0.txt)
Chris@16:  */
Chris@16: /*!
Chris@16:  * \file   channel_feature.hpp
Chris@16:  * \author Andrey Semashev
Chris@16:  * \date   28.02.2008
Chris@16:  *
Chris@16:  * The header contains implementation of a channel support feature.
Chris@16:  */
Chris@16: 
Chris@16: #ifndef BOOST_LOG_SOURCES_CHANNEL_FEATURE_HPP_INCLUDED_
Chris@16: #define BOOST_LOG_SOURCES_CHANNEL_FEATURE_HPP_INCLUDED_
Chris@16: 
Chris@16: #include <string>
Chris@16: #include <boost/move/core.hpp>
Chris@16: #include <boost/move/utility.hpp>
Chris@16: #include <boost/log/detail/config.hpp>
Chris@16: #include <boost/log/detail/locks.hpp>
Chris@16: #include <boost/log/detail/default_attribute_names.hpp>
Chris@16: #include <boost/log/keywords/channel.hpp>
Chris@16: #include <boost/log/attributes/mutable_constant.hpp>
Chris@16: #include <boost/log/utility/strictest_lock.hpp>
Chris@16: #include <boost/log/core/record.hpp>
Chris@16: #include <boost/log/detail/header.hpp>
Chris@16: 
Chris@16: #ifdef BOOST_HAS_PRAGMA_ONCE
Chris@16: #pragma once
Chris@16: #endif
Chris@16: 
Chris@16: namespace boost {
Chris@16: 
Chris@16: BOOST_LOG_OPEN_NAMESPACE
Chris@16: 
Chris@16: namespace sources {
Chris@16: 
Chris@16: /*!
Chris@16:  * \brief Channel feature implementation
Chris@16:  */
Chris@16: template< typename BaseT, typename ChannelT >
Chris@16: class basic_channel_logger :
Chris@16:     public BaseT
Chris@16: {
Chris@16:     //! Base type
Chris@16:     typedef BaseT base_type;
Chris@16:     typedef basic_channel_logger this_type;
Chris@16:     BOOST_COPYABLE_AND_MOVABLE_ALT(this_type)
Chris@16: 
Chris@16: public:
Chris@16:     //! Character type
Chris@16:     typedef typename base_type::char_type char_type;
Chris@16:     //! Final type
Chris@16:     typedef typename base_type::final_type final_type;
Chris@16:     //! Threading model being used
Chris@16:     typedef typename base_type::threading_model threading_model;
Chris@16: 
Chris@16:     //! Channel type
Chris@16:     typedef ChannelT channel_type;
Chris@16:     //! Channel attribute type
Chris@16:     typedef attributes::mutable_constant< channel_type > channel_attribute;
Chris@16: 
Chris@16:     //! Lock requirement for the \c open_record_unlocked method
Chris@16:     typedef typename strictest_lock<
Chris@16:         typename base_type::open_record_lock,
Chris@16: #ifndef BOOST_LOG_NO_THREADS
Chris@16:         boost::log::aux::exclusive_lock_guard< threading_model >
Chris@16: #else
Chris@16:         no_lock< threading_model >
Chris@16: #endif // !defined(BOOST_LOG_NO_THREADS)
Chris@16:     >::type open_record_lock;
Chris@16: 
Chris@16:     //! Lock requirement for the \c swap_unlocked method
Chris@16:     typedef typename strictest_lock<
Chris@16:         typename base_type::swap_lock,
Chris@16: #ifndef BOOST_LOG_NO_THREADS
Chris@16:         boost::log::aux::exclusive_lock_guard< threading_model >
Chris@16: #else
Chris@16:         no_lock< threading_model >
Chris@16: #endif // !defined(BOOST_LOG_NO_THREADS)
Chris@16:     >::type swap_lock;
Chris@16: 
Chris@16: private:
Chris@16:     //! Default channel name generator
Chris@16:     struct make_default_channel_name
Chris@16:     {
Chris@16:         typedef channel_type result_type;
Chris@16:         result_type operator() () const { return result_type(); }
Chris@16:     };
Chris@16: 
Chris@16: private:
Chris@16:     //! Channel attribute
Chris@16:     channel_attribute m_ChannelAttr;
Chris@16: 
Chris@16: public:
Chris@16:     /*!
Chris@16:      * Default constructor. The constructed logger has the default-constructed channel name.
Chris@16:      */
Chris@16:     basic_channel_logger() : base_type(), m_ChannelAttr(channel_type())
Chris@16:     {
Chris@16:         base_type::add_attribute_unlocked(boost::log::aux::default_attribute_names::channel(), m_ChannelAttr);
Chris@16:     }
Chris@16:     /*!
Chris@16:      * Copy constructor
Chris@16:      */
Chris@16:     basic_channel_logger(basic_channel_logger const& that) :
Chris@16:         base_type(static_cast< base_type const& >(that)),
Chris@16:         m_ChannelAttr(that.m_ChannelAttr)
Chris@16:     {
Chris@16:         base_type::attributes()[boost::log::aux::default_attribute_names::channel()] = m_ChannelAttr;
Chris@16:     }
Chris@16:     /*!
Chris@16:      * Move constructor
Chris@16:      */
Chris@16:     basic_channel_logger(BOOST_RV_REF(basic_channel_logger) that) :
Chris@16:         base_type(boost::move(static_cast< base_type& >(that))),
Chris@16:         m_ChannelAttr(boost::move(that.m_ChannelAttr))
Chris@16:     {
Chris@16:         base_type::attributes()[boost::log::aux::default_attribute_names::channel()] = m_ChannelAttr;
Chris@16:     }
Chris@16:     /*!
Chris@16:      * Constructor with arguments. Allows to register a channel name attribute on construction.
Chris@16:      *
Chris@16:      * \param args A set of named arguments. The following arguments are supported:
Chris@16:      *             \li \c channel - a string that represents the channel name
Chris@16:      */
Chris@16:     template< typename ArgsT >
Chris@16:     explicit basic_channel_logger(ArgsT const& args) :
Chris@16:         base_type(args),
Chris@16:         m_ChannelAttr(args[keywords::channel || make_default_channel_name()])
Chris@16:     {
Chris@16:         base_type::add_attribute_unlocked(boost::log::aux::default_attribute_names::channel(), m_ChannelAttr);
Chris@16:     }
Chris@16: 
Chris@16:     /*!
Chris@16:      * The observer of the channel name
Chris@16:      *
Chris@16:      * \return The channel name that was set by the logger
Chris@16:      */
Chris@16:     channel_type channel() const
Chris@16:     {
Chris@16:         BOOST_LOG_EXPR_IF_MT(boost::log::aux::shared_lock_guard< const threading_model > lock(this->get_threading_model());)
Chris@16:         return m_ChannelAttr.get();
Chris@16:     }
Chris@16: 
Chris@16:     /*!
Chris@16:      * The setter of the channel name
Chris@16:      *
Chris@16:      * \param ch The channel name to be set for the logger
Chris@16:      */
Chris@16:     void channel(channel_type const& ch)
Chris@16:     {
Chris@16:         BOOST_LOG_EXPR_IF_MT(boost::log::aux::exclusive_lock_guard< threading_model > lock(this->get_threading_model());)
Chris@16:         m_ChannelAttr.set(ch);
Chris@16:     }
Chris@16: 
Chris@16: protected:
Chris@16:     /*!
Chris@16:      * Channel attribute accessor
Chris@16:      */
Chris@16:     channel_attribute const& get_channel_attribute() const { return m_ChannelAttr; }
Chris@16: 
Chris@16:     /*!
Chris@16:      * Unlocked \c open_record
Chris@16:      */
Chris@16:     template< typename ArgsT >
Chris@16:     record open_record_unlocked(ArgsT const& args)
Chris@16:     {
Chris@16:         return open_record_with_channel_unlocked(args, args[keywords::channel | parameter::void_()]);
Chris@16:     }
Chris@16: 
Chris@16:     /*!
Chris@16:      * Unlocked swap
Chris@16:      */
Chris@16:     void swap_unlocked(basic_channel_logger& that)
Chris@16:     {
Chris@16:         base_type::swap_unlocked(static_cast< base_type& >(that));
Chris@16:         m_ChannelAttr.swap(that.m_ChannelAttr);
Chris@16:     }
Chris@16: 
Chris@16: private:
Chris@16:     //! The \c open_record implementation for the case when the channel is specified in log statement
Chris@16:     template< typename ArgsT, typename T >
Chris@16:     record open_record_with_channel_unlocked(ArgsT const& args, T const& ch)
Chris@16:     {
Chris@16:         m_ChannelAttr.set(ch);
Chris@16:         return base_type::open_record_unlocked(args);
Chris@16:     }
Chris@16:     //! The \c open_record implementation for the case when the channel is not specified in log statement
Chris@16:     template< typename ArgsT >
Chris@16:     record open_record_with_channel_unlocked(ArgsT const& args, parameter::void_)
Chris@16:     {
Chris@16:         return base_type::open_record_unlocked(args);
Chris@16:     }
Chris@16: };
Chris@16: 
Chris@16: /*!
Chris@16:  * \brief Channel support feature
Chris@16:  *
Chris@16:  * The logger with this feature automatically registers an attribute with the specified
Chris@16:  * on construction value, which is a channel name. The channel name can be modified
Chris@16:  * through the logger life time, either by calling the \c channel method or by specifying
Chris@16:  * the name in the logging statement.
Chris@16:  *
Chris@16:  * The type of the channel name can be customized by providing it as a template parameter
Chris@16:  * to the feature template. By default, a string will be used.
Chris@16:  */
Chris@16: template< typename ChannelT = std::string >
Chris@16: struct channel
Chris@16: {
Chris@16:     template< typename BaseT >
Chris@16:     struct apply
Chris@16:     {
Chris@16:         typedef basic_channel_logger<
Chris@16:             BaseT,
Chris@16:             ChannelT
Chris@16:         > type;
Chris@16:     };
Chris@16: };
Chris@16: 
Chris@16: } // namespace sources
Chris@16: 
Chris@16: BOOST_LOG_CLOSE_NAMESPACE // namespace log
Chris@16: 
Chris@16: } // namespace boost
Chris@16: 
Chris@16: //! The macro allows to put a record with a specific channel name into log
Chris@16: #define BOOST_LOG_STREAM_CHANNEL(logger, chan)\
Chris@16:     BOOST_LOG_STREAM_WITH_PARAMS((logger), (::boost::log::keywords::channel = (chan)))
Chris@16: 
Chris@16: #ifndef BOOST_LOG_NO_SHORTHAND_NAMES
Chris@16: 
Chris@16: //! An equivalent to BOOST_LOG_STREAM_CHANNEL(logger, chan)
Chris@16: #define BOOST_LOG_CHANNEL(logger, chan) BOOST_LOG_STREAM_CHANNEL(logger, chan)
Chris@16: 
Chris@16: #endif // BOOST_LOG_NO_SHORTHAND_NAMES
Chris@16: 
Chris@16: #include <boost/log/detail/footer.hpp>
Chris@16: 
Chris@16: #endif // BOOST_LOG_SOURCES_CHANNEL_FEATURE_HPP_INCLUDED_