luabind/error.hpp

   1 // Copyright (c) 2003 Daniel Wallin and Arvid Norberg
   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 LUABIND_ERROR_HPP_INCLUDED
  24 #define LUABIND_ERROR_HPP_INCLUDED
  25
  26 #include <luabind/prefix.hpp>
  27 #include <exception>
  28 #include <luabind/config.hpp>
  29
  30 namespace luabind
  31 {
  32
  33 #ifndef LUABIND_NO_EXCEPTIONS
  34
  35         // this exception usually means that the lua function you called
  36         // from C++ failed with an error code. You will have to
  37         // read the error code from the top of the lua stack
  38         // the reason why this exception class doesn't contain
  39         // the message itself is that std::string's copy constructor
  40         // may throw, if the copy constructor of an exception that is
  41         // being thrown throws another exception, terminate will be called
  42         // and the entire application is killed.
  43         class error : public std::exception
  44         {
  45         public:
  46                 error(lua_State* L): m_L(L) {}
  47                 lua_State* state() const throw() { return m_L; }
  48                 virtual const char* what() const throw()
  49                 {
  50                         return "lua runtime error";
  51                 }
  52         private:
  53                 lua_State* m_L;
  54         };
  55
  56         // if an object_cast<>() fails, this is thrown
  57         // it is also thrown if the return value of
  58         // a lua function cannot be converted
  59         class cast_failed : public std::exception
  60         {
  61         public:
  62                 cast_failed(lua_State* L, LUABIND_TYPE_INFO i): m_L(L), m_info(i) {}
  63                 lua_State* state() const throw() { return m_L; }
  64                 LUABIND_TYPE_INFO info() const throw() { return m_info; }
  65                 virtual const char* what() const throw() { return "unable to make cast"; }
  66         private:
  67                 lua_State* m_L;
  68                 LUABIND_TYPE_INFO m_info;
  69         };
  70
  71 #else
  72
  73         typedef void(*error_callback_fun)(lua_State*);
  74         typedef void(*cast_failed_callback_fun)(lua_State*, LUABIND_TYPE_INFO);
  75
  76         namespace detail
  77         {
  78                 // we use a singleton instead of a global variable
  79                 // because we want luabind to be headers only
  80
  81                 struct error_callback
  82                 {
  83                         error_callback_fun err;
  84                         cast_failed_callback_fun cast;
  85
  86                         error_callback(): err(0), cast(0) {}
  87
  88                         static error_callback& get()
  89                         {
  90                                 static error_callback instance;
  91                                 return instance;
  92                         }
  93                 };
  94         }
  95
  96         inline void set_error_callback(error_callback_fun e)
  97         {
  98                 detail::error_callback::get().err = e;
  99         }
 100
 101         inline void set_cast_failed_callback(cast_failed_callback_fun c)
 102         {
 103                 detail::error_callback::get().cast = c;
 104         }
 105
 106 #endif
 107
 108 }
 109
 110 #endif // LUABIND_ERROR_HPP_INCLUDED
 111