00001 // RTTI support for -*- C++ -*- 00002 // Copyright (C) 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 00003 // 2003, 2004, 2005, 2006, 2007 00004 // Free Software Foundation 00005 // 00006 // This file is part of GCC. 00007 // 00008 // GCC is free software; you can redistribute it and/or modify 00009 // it under the terms of the GNU General Public License as published by 00010 // the Free Software Foundation; either version 2, or (at your option) 00011 // any later version. 00012 // 00013 // GCC is distributed in the hope that it will be useful, 00014 // but WITHOUT ANY WARRANTY; without even the implied warranty of 00015 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 00016 // GNU General Public License for more details. 00017 // 00018 // You should have received a copy of the GNU General Public License 00019 // along with GCC; see the file COPYING. If not, write to 00020 // the Free Software Foundation, 51 Franklin Street, Fifth Floor, 00021 // Boston, MA 02110-1301, USA. 00022 00023 // As a special exception, you may use this file as part of a free software 00024 // library without restriction. Specifically, if other files instantiate 00025 // templates or use macros or inline functions from this file, or you compile 00026 // this file and link it with other files to produce an executable, this 00027 // file does not by itself cause the resulting executable to be covered by 00028 // the GNU General Public License. This exception does not however 00029 // invalidate any other reasons why the executable file might be covered by 00030 // the GNU General Public License. 00031 00032 /** @file typeinfo 00033 * This is a Standard C++ Library header. 00034 */ 00035 00036 #ifndef _TYPEINFO 00037 #define _TYPEINFO 00038 00039 #include <exception> 00040 00041 #pragma GCC visibility push(default) 00042 00043 extern "C++" { 00044 00045 namespace __cxxabiv1 00046 { 00047 class __class_type_info; 00048 } // namespace __cxxabiv1 00049 00050 #ifndef __GXX_MERGED_TYPEINFO_NAMES 00051 #if !__GXX_WEAK__ 00052 // If weak symbols are not supported, typeinfo names are not merged. 00053 #define __GXX_MERGED_TYPEINFO_NAMES 0 00054 #else 00055 // On platforms that support weak symbols, typeinfo names are merged. 00056 #define __GXX_MERGED_TYPEINFO_NAMES 1 00057 #endif 00058 #endif 00059 00060 namespace std 00061 { 00062 /** 00063 * @brief Part of RTTI. 00064 * 00065 * The @c type_info class describes type information generated by 00066 * an implementation. 00067 */ 00068 class type_info 00069 { 00070 public: 00071 /** Destructor first. Being the first non-inline virtual function, this 00072 * controls in which translation unit the vtable is emitted. The 00073 * compiler makes use of that information to know where to emit 00074 * the runtime-mandated type_info structures in the new-abi. */ 00075 virtual ~type_info(); 00076 00077 /** Returns an @e implementation-defined byte string; this is not 00078 * portable between compilers! */ 00079 const char* name() const 00080 { return __name; } 00081 00082 #if !__GXX_MERGED_TYPEINFO_NAMES 00083 bool before(const type_info& __arg) const; 00084 00085 // In old abi, or when weak symbols are not supported, there can 00086 // be multiple instances of a type_info object for one 00087 // type. Uniqueness must use the _name value, not object address. 00088 bool operator==(const type_info& __arg) const; 00089 #else 00090 /** Returns true if @c *this precedes @c __arg in the implementation's 00091 * collation order. */ 00092 // In new abi we can rely on type_info's NTBS being unique, 00093 // and therefore address comparisons are sufficient. 00094 bool before(const type_info& __arg) const 00095 { return __name < __arg.__name; } 00096 00097 bool operator==(const type_info& __arg) const 00098 { return __name == __arg.__name; } 00099 #endif 00100 bool operator!=(const type_info& __arg) const 00101 { return !operator==(__arg); } 00102 00103 // Return true if this is a pointer type of some kind 00104 virtual bool __is_pointer_p() const; 00105 00106 // Return true if this is a function type 00107 virtual bool __is_function_p() const; 00108 00109 // Try and catch a thrown type. Store an adjusted pointer to the 00110 // caught type in THR_OBJ. If THR_TYPE is not a pointer type, then 00111 // THR_OBJ points to the thrown object. If THR_TYPE is a pointer 00112 // type, then THR_OBJ is the pointer itself. OUTER indicates the 00113 // number of outer pointers, and whether they were const 00114 // qualified. 00115 virtual bool __do_catch(const type_info *__thr_type, void **__thr_obj, 00116 unsigned __outer) const; 00117 00118 // Internally used during catch matching 00119 virtual bool __do_upcast(const __cxxabiv1::__class_type_info *__target, 00120 void **__obj_ptr) const; 00121 00122 protected: 00123 const char *__name; 00124 00125 explicit type_info(const char *__n): __name(__n) { } 00126 00127 private: 00128 /// Assigning type_info is not supported. 00129 type_info& operator=(const type_info&); 00130 type_info(const type_info&); 00131 }; 00132 00133 /** 00134 * @brief Thrown during incorrect typecasting. 00135 * 00136 * If you attempt an invalid @c dynamic_cast expression, an instance of 00137 * this class (or something derived from this class) is thrown. */ 00138 class bad_cast : public exception 00139 { 00140 public: 00141 bad_cast() throw() { } 00142 00143 // This declaration is not useless: 00144 // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118 00145 virtual ~bad_cast() throw(); 00146 00147 // See comment in eh_exception.cc. 00148 virtual const char* what() const throw(); 00149 }; 00150 00151 /** If you use a NULL pointer in a @c typeid expression, this is thrown. */ 00152 class bad_typeid : public exception 00153 { 00154 public: 00155 bad_typeid () throw() { } 00156 00157 // This declaration is not useless: 00158 // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118 00159 virtual ~bad_typeid() throw(); 00160 00161 // See comment in eh_exception.cc. 00162 virtual const char* what() const throw(); 00163 }; 00164 } // namespace std 00165 00166 #pragma GCC visibility pop 00167 00168 } // extern "C++" 00169 #endif