ceph/src/boost/libs/log/include/boost/log/support/spirit_classic.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   support/spirit_classic.hpp
   9  * \author Andrey Semashev
  10  * \date   19.07.2009
  11  *
  12  * This header enables Boost.Spirit (classic) support for Boost.Log.
  13  */
  14
  15 #ifndef BOOST_LOG_SUPPORT_SPIRIT_CLASSIC_HPP_INCLUDED_
  16 #define BOOST_LOG_SUPPORT_SPIRIT_CLASSIC_HPP_INCLUDED_
  17
  18 #include <boost/mpl/bool.hpp>
  19 #include <boost/core/enable_if.hpp>
  20 #include <boost/log/detail/config.hpp>
  21 #include <boost/log/utility/functional/matches.hpp>
  22
  23 #ifdef BOOST_HAS_PRAGMA_ONCE
  24 #pragma once
  25 #endif
  26
  27 #if !defined(BOOST_LOG_NO_THREADS) && !defined(BOOST_SPIRIT_THREADSAFE) && !defined(BOOST_LOG_DOXYGEN_PASS)
  28 /*
  29  * As Boost.Log filters may be called in multiple threads concurrently,
  30  * this may lead to using Boost.Spirit parsers in a multithreaded context.
  31  * In order to protect parsers properly, BOOST_SPIRIT_THREADSAFE macro should
  32  * be defined.
  33  *
  34  * If we got here, it means that the user did not define that macro and we
  35  * have to define it ourselves. However, it may also lead to ODR violations
  36  * or even total ignorance of this macro, if the user has included Boost.Spirit
  37  * headers before including this header, or uses Boost.Spirit without the macro
  38  * in other translation units. The only reliable way to settle this problem is to
  39  * define the macro for the whole project (i.e. all translation units).
  40  */
  41 #if defined(__GNUC__)
  42 #pragma message "Boost.Log: Boost.Spirit requires BOOST_SPIRIT_THREADSAFE macro to be defined if parsers are used in a multithreaded context. It is strongly recommended to define this macro project-wide."
  43 #elif defined(_MSC_VER)
  44 #pragma message("Boost.Log: Boost.Spirit requires BOOST_SPIRIT_THREADSAFE macro to be defined if parsers are used in a multithreaded context. It is strongly recommended to define this macro project-wide.")
  45 #endif
  46 #define BOOST_SPIRIT_THREADSAFE 1
  47 #endif // !defined(BOOST_LOG_NO_THREADS) && !defined(BOOST_SPIRIT_THREADSAFE)
  48
  49 #include <boost/spirit/include/classic_parser.hpp>
  50
  51 #include <boost/log/detail/header.hpp>
  52
  53 namespace boost {
  54
  55 BOOST_LOG_OPEN_NAMESPACE
  56
  57 namespace aux {
  58
  59 //! This tag type is used if an expression is recognized as a Boost.Spirit.Classic expression
  60 struct boost_spirit_classic_expression_tag;
  61
  62 //! The trait verifies if the type can be converted to a Boost.Spirit (classic) parser
  63 template< typename T >
  64 struct is_spirit_classic_parser
  65 {
  66 private:
  67     typedef char yes_type;
  68     struct no_type { char dummy[2]; };
  69
  70     template< typename U >
  71     static yes_type check_spirit_classic_parser(spirit::classic::parser< U > const&);
  72     static no_type check_spirit_classic_parser(...);
  73     static T& get_T();
  74
  75 public:
  76     enum { value = sizeof(check_spirit_classic_parser(get_T())) == sizeof(yes_type) };
  77     typedef mpl::bool_< value > type;
  78 };
  79
  80 //! The metafunction detects the matching expression kind and returns a tag that is used to specialize \c match_traits
  81 template< typename ExpressionT >
  82 struct matching_expression_kind< ExpressionT, typename boost::enable_if_c< is_spirit_classic_parser< ExpressionT >::value >::type >
  83 {
  84     typedef boost_spirit_classic_expression_tag type;
  85 };
  86
  87 //! The matching function implementation
  88 template< typename ExpressionT >
  89 struct match_traits< ExpressionT, boost_spirit_classic_expression_tag >
  90 {
  91     typedef ExpressionT compiled_type;
  92     static compiled_type compile(ExpressionT const& expr) { return expr; }
  93
  94     template< typename StringT >
  95     static bool matches(StringT const& str, ExpressionT const& expr)
  96     {
  97         typedef typename StringT::const_iterator const_iterator;
  98         spirit::classic::parse_info< const_iterator > info =
  99             spirit::classic::parse(str.begin(), str.end(), expr);
 100         return info.full;
 101     }
 102 };
 103
 104 } // namespace aux
 105
 106 BOOST_LOG_CLOSE_NAMESPACE // namespace log
 107
 108 } // namespace boost
 109
 110 #include <boost/log/detail/footer.hpp>
 111
 112 #endif // BOOST_LOG_SUPPORT_SPIRIT_CLASSIC_HPP_INCLUDED_