# exception

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    00001 // Exception Handling support header for -*- C++ -*-
    00002
    00003 // Copyright (C) 1995, 1996, 1997, 1998, 2000, 2001, 2002
    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, 59 Temple Place - Suite 330,
    00021 // Boston, MA 02111-1307, 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 exception
    00033  *  This header defines several types and functions relating to the
    00034  *  handling of exceptions in a C++ program.
    00035  */
    00036
    00037 #ifndef __EXCEPTION__
    00038 #define __EXCEPTION__
    00039
    00040 extern "C++" {
    00041
    00042 namespace std
    00043 {
    00044   /**
    00045    *  @brief Base class for all library exceptions.
    00046    *
    00047    *  This is the base class for all exceptions thrown by the standard
    00048    *  library, and by certain language expressions.  You are free to derive
    00049    *  your own %exception classes, or use a different hierarchy, or to
    00050    *  throw non-class data (e.g., fundamental types).
    00051    */
    00052   class exception
    00053   {
    00054   public:
    00055     exception() throw() { }
    00056     virtual ~exception() throw();
    00057     /** Returns a C-style character string describing the general cause
    00058      *  of the current error.  */
    00059     virtual const char* what() const throw();
    00060   };
    00061
    00062   /** If an %exception is thrown which is not listed in a function's
    00063    *  %exception specification, one of these may be thrown.  */
    00064   class bad_exception : public exception
    00065   {
    00066   public:
    00067     bad_exception() throw() { }
    00068     // This declaration is not useless:
    00069     // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118
    00070     virtual ~bad_exception() throw();
    00071   };
    00072
    00073   /// If you write a replacement %terminate handler, it must be of this type.
    00074   typedef void (*terminate_handler) ();
    00075   /// If you write a replacement %unexpected handler, it must be of this type.
    00076   typedef void (*unexpected_handler) ();
    00077
    00078   /// Takes a new handler function as an argument, returns the old function.
    00079   terminate_handler set_terminate(terminate_handler) throw();
    00080   /** The runtime will call this function if %exception handling must be
    00081    *  abandoned for any reason.  It can also be called by the user.  */
    00082   void terminate() __attribute__ ((__noreturn__));
    00083
    00084   /// Takes a new handler function as an argument, returns the old function.
    00085   unexpected_handler set_unexpected(unexpected_handler) throw();
    00086   /** The runtime will call this function if an %exception is thrown which
    00087    *  violates the function's %exception specification.  */
    00088   void unexpected() __attribute__ ((__noreturn__));
    00089
    00090   /** [18.6.4]/1:  "Returns true after completing evaluation of a
    00091    *  throw-expression until either completing initialization of the
    00092    *  exception-declaration in the matching handler or entering @c unexpected()
    00093    *  due to the throw; or after entering @c terminate() for any reason
    00094    *  other than an explicit call to @c terminate().  [Note: This includes
    00095    *  stack unwinding [15.2].  end note]"
    00096    *
    00097    *  2:  "When @c uncaught_exception() is true, throwing an %exception can
    00098    *  result in a call of @c terminate() (15.5.1)."
    00099    */
    00100   bool uncaught_exception() throw();
    00101 } // namespace std
    00102
    00103 namespace __gnu_cxx
    00104 {
    00105   /** A replacement for the standard terminate_handler which prints more
    00106       information about the terminating exception (if any) on stderr.  Call
    00107       @code
    00108         std::set_terminate (__gnu_cxx::__verbose_terminate_handler)
    00109       @endcode
    00110       to use.  For more info, see
    00111       http://gcc.gnu.org/onlinedocs/libstdc++/19_diagnostics/howto.html#4
    00112
    00113       In 3.4 and later, this is on by default.
    00114   */
    00115   void __verbose_terminate_handler ();
    00116 } // namespace __gnu_cxx
    00117
    00118 } // extern "C++"
    00119
    00120 #endif