# typeinfo

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    00001 // RTTI support for -*- C++ -*-
    00002 // Copyright (C) 1994, 1995, 1996, 1997, 1998, 2000, 2001, 2002
    00003 // Free Software Foundation
    00004 //
    00005 // This file is part of GCC.
    00006 //
    00007 // GCC is free software; you can redistribute it and/or modify
    00008 // it under the terms of the GNU General Public License as published by
    00009 // the Free Software Foundation; either version 2, or (at your option)
    00010 // any later version.
    00011 //
    00012 // GCC is distributed in the hope that it will be useful,
    00013 // but WITHOUT ANY WARRANTY; without even the implied warranty of
    00014 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    00015 // GNU General Public License for more details.
    00016 //
    00017 // You should have received a copy of the GNU General Public License
    00018 // along with GCC; see the file COPYING.  If not, write to
    00019 // the Free Software Foundation, 59 Temple Place - Suite 330,
    00020 // Boston, MA 02111-1307, USA.
    00021
    00022 // As a special exception, you may use this file as part of a free software
    00023 // library without restriction.  Specifically, if other files instantiate
    00024 // templates or use macros or inline functions from this file, or you compile
    00025 // this file and link it with other files to produce an executable, this
    00026 // file does not by itself cause the resulting executable to be covered by
    00027 // the GNU General Public License.  This exception does not however
    00028 // invalidate any other reasons why the executable file might be covered by
    00029 // the GNU General Public License.
    00030
    00031 /** @file typeinfo
    00032  *  This header provides RTTI support.
    00033  */
    00034
    00035 #ifndef _TYPEINFO
    00036 #define _TYPEINFO
    00037
    00038 #include <exception>
    00039
    00040 #pragma GCC visibility push(default)
    00041
    00042 extern "C++" {
    00043
    00044 namespace __cxxabiv1
    00045 {
    00046   class __class_type_info;
    00047 } // namespace __cxxabiv1
    00048
    00049 #ifndef __GXX_MERGED_TYPEINFO_NAMES
    00050   #if !__GXX_WEAK__
    00051     // If weak symbols are not supported, typeinfo names are not merged.
    00052     #define __GXX_MERGED_TYPEINFO_NAMES 0
    00053   #else
    00054     // On platforms that support weak symbols, typeinfo names are merged.
    00055     #define __GXX_MERGED_TYPEINFO_NAMES 1
    00056   #endif
    00057 #endif
    00058
    00059 namespace std
    00060 {
    00061   /**
    00062    *  @brief  Part of RTTI.
    00063    *
    00064    *  The @c type_info class describes type information generated by
    00065    *  an implementation.
    00066   */
    00067   class type_info
    00068   {
    00069   public:
    00070     /** Destructor. Being the first non-inline virtual function, this
    00071      *  controls in which translation unit the vtable is emitted. The
    00072      *  compiler makes use of that information to know where to emit
    00073      *  the runtime-mandated type_info structures in the new-abi.  */
    00074     virtual ~type_info();
    00075
    00076   private:
    00077     /// Assigning type_info is not supported.  Made private.
    00078     type_info& operator=(const type_info&);
    00079     type_info(const type_info&);
    00080
    00081   protected:
    00082     const char *__name;
    00083
    00084   protected:
    00085     explicit type_info(const char *__n): __name(__n) { }
    00086
    00087   public:
    00088     // the public interface
    00089     /** Returns an @e implementation-defined byte string; this is not
    00090      *  portable between compilers!  */
    00091     const char* name() const
    00092     { return __name; }
    00093
    00094 #if !__GXX_MERGED_TYPEINFO_NAMES
    00095     bool before(const type_info& __arg) const;
    00096     // In old abi, or when weak symbols are not supported, there can
    00097     // be multiple instances of a type_info object for one
    00098     // type. Uniqueness must use the _name value, not object address.
    00099     bool operator==(const type_info& __arg) const;
    00100 #else
    00101     /** Returns true if @c *this precedes @c __arg in the implementation's
    00102      *  collation order.  */
    00103     // In new abi we can rely on type_info's NTBS being unique,
    00104     // and therefore address comparisons are sufficient.
    00105     bool before(const type_info& __arg) const
    00106     { return __name < __arg.__name; }
    00107     bool operator==(const type_info& __arg) const
    00108     { return __name == __arg.__name; }
    00109 #endif
    00110     bool operator!=(const type_info& __arg) const
    00111     { return !operator==(__arg); }
    00112
    00113     // the internal interface
    00114   public:
    00115     // return true if this is a pointer type of some kind
    00116     virtual bool __is_pointer_p() const;
    00117     // return true if this is a function type
    00118     virtual bool __is_function_p() const;
    00119
    00120     // Try and catch a thrown type. Store an adjusted pointer to the
    00121     // caught type in THR_OBJ. If THR_TYPE is not a pointer type, then
    00122     // THR_OBJ points to the thrown object. If THR_TYPE is a pointer
    00123     // type, then THR_OBJ is the pointer itself. OUTER indicates the
    00124     // number of outer pointers, and whether they were const
    00125     // qualified.
    00126     virtual bool __do_catch(const type_info *__thr_type, void **__thr_obj,
    00127                 unsigned __outer) const;
    00128
    00129     // internally used during catch matching
    00130     virtual bool __do_upcast(const __cxxabiv1::__class_type_info *__target,
    00131                  void **__obj_ptr) const;
    00132   };
    00133
    00134   /**
    00135    *  @brief  Thrown during incorrect typecasting.
    00136    *
    00137    *  If you attempt an invalid @c dynamic_cast expression, an instance of
    00138    *  this class (or something derived from this class) is thrown.  */
    00139   class bad_cast : public exception
    00140   {
    00141   public:
    00142     bad_cast() throw() { }
    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
    00148   /** If you use a NULL pointer in a @c typeid expression, this is thrown.  */
    00149   class bad_typeid : public exception
    00150   {
    00151   public:
    00152     bad_typeid () throw() { }
    00153     // This declaration is not useless:
    00154     // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118
    00155     virtual ~bad_typeid() throw();
    00156   };
    00157 } // namespace std
    00158
    00159 #pragma GCC visibility pop
    00160
    00161 } // extern "C++"
    00162 #endif