1 #ifndef BOOST_STATECHART_DETAIL_RTTI_POLICY_HPP_INCLUDED 2 #define BOOST_STATECHART_DETAIL_RTTI_POLICY_HPP_INCLUDED 3 ////////////////////////////////////////////////////////////////////////////// 4 // Copyright 2002-2008 Andreas Huber Doenni 5 // Distributed under the Boost Software License, Version 1.0. (See accompany- 6 // ing file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) 7 ////////////////////////////////////////////////////////////////////////////// 8 9 10 11 #include <boost/assert.hpp> 12 #include <boost/config.hpp> // BOOST_MSVC 13 #include <boost/detail/workaround.hpp> 14 15 #include <typeinfo> // std::type_info 16 17 18 19 namespace boost 20 { 21 namespace statechart 22 { 23 namespace detail 24 { 25 26 27 28 ////////////////////////////////////////////////////////////////////////////// 29 struct id_provider 30 { 31 const void * pCustomId_; 32 #if defined( BOOST_ENABLE_ASSERT_HANDLER ) || !defined( NDEBUG ) 33 const std::type_info * pCustomIdType_; 34 #endif 35 }; 36 37 template< class MostDerived > 38 struct id_holder 39 { 40 static id_provider idProvider_; 41 }; 42 43 template< class MostDerived > 44 id_provider id_holder< MostDerived >::idProvider_; 45 46 47 48 ////////////////////////////////////////////////////////////////////////////// 49 struct rtti_policy 50 { 51 #ifdef BOOST_STATECHART_USE_NATIVE_RTTI 52 class id_type 53 { 54 public: 55 //////////////////////////////////////////////////////////////////////// id_type(const std::type_info & id)56 explicit id_type( const std::type_info & id ) : id_( id ) {} 57 operator ==(id_type right) const58 bool operator==( id_type right ) const 59 { 60 return ( id_ == right.id_ ) != 0; 61 } operator !=(id_type right) const62 bool operator!=( id_type right ) const { return !( *this == right ); } 63 operator <(id_type right) const64 bool operator<( id_type right ) const 65 { 66 return id_.before( right.id_ ) != 0; 67 } operator >(id_type right) const68 bool operator>( id_type right ) const { return right < *this; } operator >=(id_type right) const69 bool operator>=( id_type right ) const { return !( *this < right ); } operator <=(id_type right) const70 bool operator<=( id_type right ) const { return !( right < *this ); } 71 72 private: 73 //////////////////////////////////////////////////////////////////////// 74 const std::type_info & id_; 75 }; 76 77 typedef bool id_provider_type; // dummy 78 #else 79 typedef const void * id_type; 80 typedef const id_provider * id_provider_type; 81 #endif 82 83 //////////////////////////////////////////////////////////////////////////// 84 template< class Base > 85 class rtti_base_type : public Base 86 { 87 public: 88 //////////////////////////////////////////////////////////////////////// 89 typedef rtti_policy::id_type id_type; 90 dynamic_type() const91 id_type dynamic_type() const 92 { 93 #ifdef BOOST_STATECHART_USE_NATIVE_RTTI 94 return id_type( typeid( *this ) ); 95 #else 96 return idProvider_; 97 #endif 98 } 99 100 #ifndef BOOST_STATECHART_USE_NATIVE_RTTI 101 template< typename CustomId > custom_dynamic_type_ptr() const102 const CustomId * custom_dynamic_type_ptr() const 103 { 104 BOOST_ASSERT( 105 ( idProvider_->pCustomId_ == 0 ) || 106 ( *idProvider_->pCustomIdType_ == typeid( CustomId ) ) ); 107 return static_cast< const CustomId * >( idProvider_->pCustomId_ ); 108 } 109 #endif 110 111 protected: 112 #ifdef BOOST_STATECHART_USE_NATIVE_RTTI rtti_base_type(id_provider_type)113 rtti_base_type( id_provider_type ) {} 114 115 //////////////////////////////////////////////////////////////////////// 116 #if BOOST_WORKAROUND( __GNUC__, BOOST_TESTED_AT( 4 ) ) 117 // We make the destructor virtual for GCC because with this compiler 118 // there is currently no way to disable the "has virtual functions but 119 // non-virtual destructor" warning on a class by class basis. Although 120 // it can be done on the compiler command line with 121 // -Wno-non-virtual-dtor, this is undesirable as this would also 122 // suppress legitimate warnings for types that are not states. ~rtti_base_type()123 virtual ~rtti_base_type() {} 124 #else ~rtti_base_type()125 ~rtti_base_type() {} 126 #endif 127 128 private: 129 //////////////////////////////////////////////////////////////////////// 130 // For typeid( *this ) to return a value that corresponds to the most- 131 // derived type, we need to have a vptr. Since this type does not 132 // contain any virtual functions we need to artificially declare one so. dummy()133 virtual void dummy() {} 134 #else 135 rtti_base_type( 136 id_provider_type idProvider 137 ) : 138 idProvider_( idProvider ) 139 { 140 } 141 142 ~rtti_base_type() {} 143 144 private: 145 //////////////////////////////////////////////////////////////////////// 146 id_provider_type idProvider_; 147 #endif 148 }; 149 150 //////////////////////////////////////////////////////////////////////////// 151 template< class MostDerived, class Base > 152 class rtti_derived_type : public Base 153 { 154 public: 155 //////////////////////////////////////////////////////////////////////// static_type()156 static id_type static_type() 157 { 158 #ifdef BOOST_STATECHART_USE_NATIVE_RTTI 159 return id_type( typeid( const MostDerived ) ); 160 #else 161 return &id_holder< MostDerived >::idProvider_; 162 #endif 163 } 164 165 #ifndef BOOST_STATECHART_USE_NATIVE_RTTI 166 template< class CustomId > custom_static_type_ptr()167 static const CustomId * custom_static_type_ptr() 168 { 169 BOOST_ASSERT( 170 ( id_holder< MostDerived >::idProvider_.pCustomId_ == 0 ) || 171 ( *id_holder< MostDerived >::idProvider_.pCustomIdType_ == 172 typeid( CustomId ) ) ); 173 return static_cast< const CustomId * >( 174 id_holder< MostDerived >::idProvider_.pCustomId_ ); 175 } 176 177 template< class CustomId > custom_static_type_ptr(const CustomId * pCustomId)178 static void custom_static_type_ptr( const CustomId * pCustomId ) 179 { 180 #if defined( BOOST_ENABLE_ASSERT_HANDLER ) || !defined( NDEBUG ) 181 id_holder< MostDerived >::idProvider_.pCustomIdType_ = 182 &typeid( CustomId ); 183 #endif 184 id_holder< MostDerived >::idProvider_.pCustomId_ = pCustomId; 185 } 186 #endif 187 188 protected: 189 //////////////////////////////////////////////////////////////////////// ~rtti_derived_type()190 ~rtti_derived_type() {} 191 192 #ifdef BOOST_STATECHART_USE_NATIVE_RTTI rtti_derived_type()193 rtti_derived_type() : Base( false ) {} 194 #else rtti_derived_type()195 rtti_derived_type() : Base( &id_holder< MostDerived >::idProvider_ ) {} 196 #endif 197 }; 198 }; 199 200 201 202 } // namespace detail 203 } // namespace statechart 204 } // namespace boost 205 206 207 208 #endif 209