include/luabind/detail/class_cache.hpp

   1 // Copyright (c) 2004 Daniel Wallin
   2
   3 // Permission is hereby granted, free of charge, to any person obtaining a
   4 // copy of this software and associated documentation files (the "Software"),
   5 // to deal in the Software without restriction, including without limitation
   6 // the rights to use, copy, modify, merge, publish, distribute, sublicense,
   7 // and/or sell copies of the Software, and to permit persons to whom the
   8 // Software is furnished to do so, subject to the following conditions:
   9
  10 // The above copyright notice and this permission notice shall be included
  11 // in all copies or substantial portions of the Software.
  12
  13 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
  14 // ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
  15 // TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
  16 // PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
  17 // SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
  18 // ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  19 // ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  20 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE
  21 // OR OTHER DEALINGS IN THE SOFTWARE.
  22
  23 #ifndef CLASS_CACHE_040218_HPP
  24 #define CLASS_CACHE_040218_HPP
  25
  26 #include <luabind/prefix.hpp>
  27 #include <boost/type_traits/add_reference.hpp>
  28 #include <boost/type_traits/add_const.hpp>
  29
  30 namespace luabind { namespace detail {
  31
  32 #ifdef LUABIND_NOT_THREADSAFE
  33
  34     class class_rep;
  35
  36     template<class T>
  37     struct class_cache_impl
  38     {
  39         static lua_State* state;
  40         static class_rep* class_;
  41     };
  42
  43     template<class T>
  44     lua_State* class_cache_impl<T>::state = 0;
  45
  46     template<class T>
  47     class_rep* class_cache_impl<T>::class_ = 0;
  48
  49     template<class T>
  50     struct class_cache
  51         : class_cache_impl<
  52               typename boost::add_reference<
  53                   typename boost::add_const<
  54                       T
  55                   >::type
  56               >::type
  57           >
  58     {
  59     };
  60
  61     template<class T>
  62     class_rep* get_class_rep(lua_State* L, void(*)(T*) = 0)
  63     {
  64         if (class_cache<T>::state != L)
  65         {
  66             class_cache<T>::state = L;
  67
  68             class_registry* registry = class_registry::get_registry(L);
  69                         class_cache<T>::class_ = registry->find_class(LUABIND_TYPEID(T));
  70         }
  71
  72         return class_cache<T>::class_;
  73     }
  74
  75 #else
  76
  77     template<class T>
  78     class_rep* get_class_rep(lua_State* L, void(*)(T*) = 0)
  79     {
  80         class_registry* registry = class_registry::get_registry(L);
  81         return registry->find_class(LUABIND_TYPEID(T));
  82     }
  83
  84 #endif
  85
  86 }} // namespace luabind::detail
  87
  88 #endif // CLASS_CACHE_040218_HPP
  89