boost/serialization/export.hpp

   1 #ifndef BOOST_SERIALIZATION_EXPORT_HPP
   2 #define BOOST_SERIALIZATION_EXPORT_HPP
   3
   4 // MS compatible compilers support #pragma once
   5 #if defined(_MSC_VER) && (_MSC_VER >= 1020)
   6 # pragma once
   7 #endif
   8
   9 /////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
  10 // export.hpp: set traits of classes to be serialized
  11
  12 // (C) Copyright 2002 Robert Ramey - http://www.rrsd.com .
  13 // Use, modification and distribution is subject to the Boost Software
  14 // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
  15 // http://www.boost.org/LICENSE_1_0.txt)
  16
  17 //  See http://www.boost.org for updates, documentation, and revision history.
  18
  19 // (C) Copyright 2006 David Abrahams - http://www.boost.org.
  20 // implementation of class export functionality.  This is an alternative to
  21 // "forward declaration" method to provoke instantiation of derived classes
  22 // that are to be serialized through pointers.
  23
  24 #include <utility>
  25 #include <cstddef> // NULL
  26
  27 #include <boost/config.hpp>
  28 #include <boost/static_assert.hpp>
  29 #include <boost/preprocessor/stringize.hpp>
  30 #include <boost/type_traits/is_polymorphic.hpp>
  31
  32 #ifndef BOOST_SERIALIZATION_DEFAULT_TYPE_INFO
  33     #include <boost/serialization/extended_type_info_typeid.hpp>
  34 #endif
  35 #include <boost/serialization/static_warning.hpp>
  36 #include <boost/serialization/type_info_implementation.hpp>
  37 #include <boost/serialization/assume_abstract.hpp>
  38 #include <boost/serialization/force_include.hpp>
  39 #include <boost/serialization/singleton.hpp>
  40
  41 #include <boost/archive/detail/register_archive.hpp>
  42 #include <boost/mpl/assert.hpp>
  43 #include <boost/mpl/and.hpp>
  44 #include <boost/mpl/not.hpp>
  45 #include <boost/mpl/bool.hpp>
  46
  47 #include <iostream>
  48
  49 namespace boost {
  50 namespace archive {
  51 namespace detail {
  52
  53 class basic_pointer_iserializer;
  54 class basic_pointer_oserializer;
  55
  56 template<class Archive, class T>
  57 class pointer_iserializer;
  58 template<class Archive, class T>
  59 class pointer_oserializer;
  60
  61 template <class Archive, class Serializable>
  62 struct export_impl
  63 {
  64     static const basic_pointer_iserializer &
  65     enable_load(mpl::true_){
  66         return boost::serialization::singleton<
  67             pointer_iserializer<Archive, Serializable>
  68         >::get_const_instance();
  69     }
  70
  71     static const basic_pointer_oserializer &
  72     enable_save(mpl::true_){
  73         return boost::serialization::singleton<
  74             pointer_oserializer<Archive, Serializable>
  75         >::get_const_instance();
  76     }
  77     inline static void enable_load(mpl::false_) {}
  78     inline static void enable_save(mpl::false_) {}
  79 };
  80
  81 // On many platforms, naming a specialization of this template is
  82 // enough to cause its argument to be instantiated.
  83 template <void(*)()>
  84 struct instantiate_function {};
  85
  86 template <class Archive, class Serializable>
  87 struct ptr_serialization_support
  88 {
  89 # if defined(BOOST_MSVC) || defined(__SUNPRO_CC)
  90     virtual BOOST_DLLEXPORT void instantiate() BOOST_USED;
  91 # elif defined(__BORLANDC__)
  92     static BOOST_DLLEXPORT void instantiate() BOOST_USED;
  93     enum { x = sizeof(instantiate(),3) };
  94 # else
  95     static BOOST_DLLEXPORT void instantiate() BOOST_USED;
  96     typedef instantiate_function<
  97         &ptr_serialization_support::instantiate
  98     > x;
  99 # endif
 100 };
 101
 102 template <class Archive, class Serializable>
 103 BOOST_DLLEXPORT void
 104 ptr_serialization_support<Archive,Serializable>::instantiate()
 105 {
 106     export_impl<Archive,Serializable>::enable_save(
 107         #if ! defined(__BORLANDC__)
 108         BOOST_DEDUCED_TYPENAME
 109         #endif
 110         Archive::is_saving()
 111     );
 112
 113     export_impl<Archive,Serializable>::enable_load(
 114         #if ! defined(__BORLANDC__)
 115         BOOST_DEDUCED_TYPENAME
 116         #endif
 117         Archive::is_loading()
 118     );
 119 }
 120
 121 namespace {
 122
 123 template<class T>
 124 struct guid_initializer
 125 {
 126     const guid_initializer & export_guid(char const* /* key */, mpl::false_){
 127         // generates the statically-initialized objects whose constructors
 128         // register the information allowing serialization of T objects
 129         // through pointers to their base classes.
 130         instantiate_ptr_serialization((T*)0, 0, adl_tag());
 131         return *this;
 132     }
 133     const guid_initializer & export_guid(char const* /*key*/, mpl::true_){
 134         return *this;
 135     }
 136     const guid_initializer & export_guid(char const* key){
 137         BOOST_STATIC_WARNING(boost::is_polymorphic<T>::value);
 138         assert(NULL != key);
 139         boost::serialization::singleton<
 140             BOOST_DEDUCED_TYPENAME
 141             boost::serialization::type_info_implementation<T>::type
 142         >::get_mutable_instance().key_register(key);
 143         // note: exporting an abstract base class will have no effect
 144         // and cannot be used to instantitiate serialization code
 145         // (one might be using this in a DLL to instantiate code)
 146         //BOOST_STATIC_WARNING(! boost::serialization::is_abstract<T>::value);
 147         return export_guid(key, boost::serialization::is_abstract<T>());
 148     }
 149 };
 150
 151 template<typename T>
 152 struct init_guid;
 153
 154 } // anonymous
 155 } // namespace detail
 156 } // namespace archive
 157 } // namespace boost
 158
 159 #define BOOST_CLASS_EXPORT_GUID(T, K)                                  \
 160     namespace boost {                                                  \
 161     namespace archive {                                                \
 162     namespace detail {                                                 \
 163     namespace {                                                        \
 164     template<>                                                         \
 165     struct init_guid< T > {                                            \
 166         static ::boost::archive::detail::guid_initializer< T > const   \
 167             & guid_initializer;                                        \
 168     };                                                                 \
 169     ::boost::archive::detail::guid_initializer< T > const &            \
 170         ::boost::archive::detail::init_guid< T >::guid_initializer =   \
 171            ::boost::serialization::singleton<                          \
 172                ::boost::archive::detail::guid_initializer< T >         \
 173            >::get_mutable_instance().export_guid(K);                   \
 174     }}}}                                                                \
 175 /**/
 176
 177 #if BOOST_WORKAROUND(__MWERKS__, BOOST_TESTED_AT(0x3205))
 178
 179 // CodeWarrior fails to construct static members of class templates
 180 // when they are instantiated from within templates, so on that
 181 // compiler we ask users to specifically register base/derived class
 182 // relationships for exported classes.  On all other compilers, use of
 183 // this macro is entirely optional.
 184 # define BOOST_SERIALIZATION_MWERKS_BASE_AND_DERIVED(Base,Derived)                  \
 185 namespace {                                                                         \
 186   static int BOOST_PP_CAT(boost_serialization_mwerks_init_, __LINE__) =             \
 187   (::boost::archive::detail::instantiate_ptr_serialization((Derived*)0,0), 3);      \
 188   static int BOOST_PP_CAT(boost_serialization_mwerks_init2_, __LINE__) = (          \
 189       ::boost::serialization::void_cast_register((Derived*)0,(Base*)0)              \
 190     , 3);                                                                           \
 191 }
 192
 193 #else
 194
 195 # define BOOST_SERIALIZATION_MWERKS_BASE_AND_DERIVED(Base,Derived)
 196
 197 #endif
 198
 199 // check for unnecessary export.  T isn't polymorphic so there is no
 200 // need to export it.
 201 #define BOOST_CLASS_EXPORT_CHECK(T)                              \
 202     BOOST_STATIC_WARNING(                                        \
 203         boost::is_polymorphic<U>::value                          \
 204     );                                                           \
 205     /**/
 206
 207 // the default exportable class identifier is the class name
 208 // the default list of archives types for which code id generated
 209 // are the originally included with this serialization system
 210 #define BOOST_CLASS_EXPORT(T)                   \
 211     BOOST_CLASS_EXPORT_GUID(                    \
 212         T,                                      \
 213         BOOST_PP_STRINGIZE(T)                   \
 214     )                                           \
 215     /**/
 216
 217 #endif // BOOST_SERIALIZATION_EXPORT_HPP
 218