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