ceph/src/boost/libs/log/include/boost/log/utility/setup/formatter_parser.hpp

   1 /*
   2  *          Copyright Andrey Semashev 2007 - 2015.
   3  * Distributed under the Boost Software License, Version 1.0.
   4  *    (See accompanying file LICENSE_1_0.txt or copy at
   5  *          http://www.boost.org/LICENSE_1_0.txt)
   6  */
   7 /*!
   8  * \file   formatter_parser.hpp
   9  * \author Andrey Semashev
  10  * \date   07.04.2008
  11  *
  12  * The header contains definition of a formatter parser function, along with facilities to
  13  * add support for custom formatters.
  14  */
  15
  16 #ifndef BOOST_LOG_UTILITY_SETUP_FORMATTER_PARSER_HPP_INCLUDED_
  17 #define BOOST_LOG_UTILITY_SETUP_FORMATTER_PARSER_HPP_INCLUDED_
  18
  19 #include <iosfwd>
  20 #include <map>
  21 #include <string>
  22 #include <boost/smart_ptr/shared_ptr.hpp>
  23 #include <boost/smart_ptr/make_shared_object.hpp>
  24 #include <boost/core/enable_if.hpp>
  25 #include <boost/type_traits/is_base_and_derived.hpp>
  26 #include <boost/log/detail/setup_config.hpp>
  27 #include <boost/log/attributes/attribute_name.hpp>
  28 #include <boost/log/core/record.hpp>
  29 #include <boost/log/expressions/formatter.hpp>
  30 #include <boost/log/expressions/attr.hpp>
  31 #include <boost/log/expressions/formatters/stream.hpp>
  32 #include <boost/log/detail/header.hpp>
  33
  34 #ifdef BOOST_HAS_PRAGMA_ONCE
  35 #pragma once
  36 #endif
  37
  38 namespace boost {
  39
  40 BOOST_LOG_OPEN_NAMESPACE
  41
  42 /*!
  43  * Formatter factory base interface.
  44  */
  45 template< typename CharT >
  46 struct formatter_factory
  47 {
  48     //! Character type
  49     typedef CharT char_type;
  50     //! String type
  51     typedef std::basic_string< char_type > string_type;
  52     //! The formatter function object
  53     typedef basic_formatter< char_type > formatter_type;
  54     /*!
  55      * Type of the map of formatter factory arguments [argument name -> argument value].
  56      * This type of maps will be passed to formatter factories on attempt to create a formatter.
  57      */
  58     typedef std::map< string_type, string_type > args_map;
  59
  60     /*!
  61      * Default constructor
  62      */
  63     BOOST_DEFAULTED_FUNCTION(formatter_factory(), {})
  64
  65     /*!
  66      * Virtual destructor
  67      */
  68     virtual ~formatter_factory() {}
  69
  70     /*!
  71      * The function creates a formatter for the specified attribute.
  72      *
  73      * \param name Attribute name
  74      * \param args Formatter arguments
  75      */
  76     virtual formatter_type create_formatter(attribute_name const& name, args_map const& args) = 0;
  77
  78     BOOST_DELETED_FUNCTION(formatter_factory(formatter_factory const&))
  79     BOOST_DELETED_FUNCTION(formatter_factory& operator= (formatter_factory const&))
  80 };
  81
  82 /*!
  83  * Base class for formatter factories. This class provides default implementation of formatter expressions for
  84  * types supporting stream output. The factory does not take into account any additional parameters that may be specified.
  85  */
  86 template< typename CharT, typename AttributeValueT >
  87 class basic_formatter_factory :
  88     public formatter_factory< CharT >
  89 {
  90 private:
  91     typedef formatter_factory< CharT > base_type;
  92
  93 public:
  94     //! Attribute value type
  95     typedef AttributeValueT value_type;
  96     //  Type imports from the base class
  97     typedef typename base_type::formatter_type formatter_type;
  98     typedef typename base_type::args_map args_map;
  99
 100     /*!
 101      * The function creates a formatter for the specified attribute.
 102      *
 103      * \param name Attribute name
 104      * \param args Formatter arguments
 105      */
 106     formatter_type create_formatter(attribute_name const& name, args_map const& args)
 107     {
 108         return formatter_type(expressions::stream << expressions::attr< value_type >(name));
 109     }
 110 };
 111
 112 /*!
 113  * \brief The function registers a user-defined formatter factory
 114  *
 115  * The function registers a user-defined formatter factory. The registered factory function will be
 116  * called when the formatter parser detects the specified attribute name in the formatter string.
 117  *
 118  * \pre <tt>!!attr_name && !!factory</tt>.
 119  *
 120  * \param attr_name Attribute name
 121  * \param factory Pointer to the formatter factory
 122  */
 123 template< typename CharT >
 124 BOOST_LOG_SETUP_API void register_formatter_factory(
 125     attribute_name const& attr_name, shared_ptr< formatter_factory< CharT > > const& factory);
 126
 127 /*!
 128  * \brief The function registers a user-defined formatter factory
 129  *
 130  * The function registers a user-defined formatter factory. The registered factory function will be
 131  * called when the formatter parser detects the specified attribute name in the formatter string.
 132  *
 133  * \pre <tt>!!attr_name && !!factory</tt>.
 134  *
 135  * \param attr_name Attribute name
 136  * \param factory Pointer to the formatter factory
 137  */
 138 template< typename FactoryT >
 139 inline typename boost::enable_if_c<
 140     is_base_and_derived< formatter_factory< typename FactoryT::char_type >, FactoryT >::value
 141 >::type register_formatter_factory(attribute_name const& attr_name, shared_ptr< FactoryT > const& factory)
 142 {
 143     typedef formatter_factory< typename FactoryT::char_type > factory_base;
 144     register_formatter_factory(attr_name, boost::static_pointer_cast< factory_base >(factory));
 145 }
 146
 147 /*!
 148  * \brief The function registers a simple formatter factory
 149  *
 150  * The function registers a simple formatter factory. The registered factory will generate formatters
 151  * that will be equivalent to the <tt>log::expressions::attr</tt> formatter (i.e. that will use the
 152  * native \c operator<< to format the attribute value). The factory does not use any arguments from the format string,
 153  * if specified.
 154  *
 155  * \pre <tt>!!attr_name</tt>.
 156  *
 157  * \param attr_name Attribute name
 158  */
 159 template< typename AttributeValueT, typename CharT >
 160 inline void register_simple_formatter_factory(attribute_name const& attr_name)
 161 {
 162     shared_ptr< formatter_factory< CharT > > factory =
 163         boost::make_shared< basic_formatter_factory< CharT, AttributeValueT > >();
 164     register_formatter_factory(attr_name, factory);
 165 }
 166
 167 /*!
 168  * The function parses a formatter from the sequence of characters
 169  *
 170  * \pre <tt>begin <= end</tt>, both pointers must not be NULL
 171  * \param begin Pointer to the first character of the sequence
 172  * \param end Pointer to the after-the-last character of the sequence
 173  * \return The parsed formatter.
 174  *
 175  * \b Throws: An <tt>std::exception</tt>-based exception, if a formatter cannot be recognized in the character sequence.
 176  */
 177 template< typename CharT >
 178 BOOST_LOG_SETUP_API basic_formatter< CharT > parse_formatter(const CharT* begin, const CharT* end);
 179
 180 /*!
 181  * The function parses a formatter from the string
 182  *
 183  * \param str A string that contains format description
 184  * \return The parsed formatter.
 185  *
 186  * \b Throws: An <tt>std::exception</tt>-based exception, if a formatter cannot be recognized in the character sequence.
 187  */
 188 template< typename CharT, typename TraitsT, typename AllocatorT >
 189 inline basic_formatter< CharT > parse_formatter(std::basic_string< CharT, TraitsT, AllocatorT > const& str)
 190 {
 191     const CharT* p = str.c_str();
 192     return parse_formatter(p, p + str.size());
 193 }
 194
 195 /*!
 196  * The function parses a formatter from the string
 197  *
 198  * \pre <tt>str != NULL</tt>, <tt>str</tt> points to a zero-terminated string
 199  * \param str A string that contains format description.
 200  * \return The parsed formatter.
 201  *
 202  * \b Throws: An <tt>std::exception</tt>-based exception, if a formatter cannot be recognized in the character sequence.
 203  */
 204 template< typename CharT >
 205 inline basic_formatter< CharT > parse_formatter(const CharT* str)
 206 {
 207     return parse_formatter(str, str + std::char_traits< CharT >::length(str));
 208 }
 209
 210 BOOST_LOG_CLOSE_NAMESPACE // namespace log
 211
 212 } // namespace boost
 213
 214 #include <boost/log/detail/footer.hpp>
 215
 216 #endif // BOOST_LOG_UTILITY_SETUP_FORMATTER_PARSER_HPP_INCLUDED_