libstdc++-v3/libsupc++/exception

   1 // Exception Handling support header for -*- C++ -*-
   2
   3 // Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003,
   4 // 2004, 2005, 2006, 2007, 2008
   5 // Free Software Foundation
   6 //
   7 // This file is part of GCC.
   8 //
   9 // GCC is free software; you can redistribute it and/or modify
  10 // it under the terms of the GNU General Public License as published by
  11 // the Free Software Foundation; either version 2, or (at your option)
  12 // any later version.
  13 //
  14 // GCC is distributed in the hope that it will be useful,
  15 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  16 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17 // GNU General Public License for more details.
  18 //
  19 // You should have received a copy of the GNU General Public License
  20 // along with GCC; see the file COPYING.  If not, write to
  21 // the Free Software Foundation, 51 Franklin Street, Fifth Floor,
  22 // Boston, MA 02110-1301, USA.
  23
  24 // As a special exception, you may use this file as part of a free software
  25 // library without restriction.  Specifically, if other files instantiate
  26 // templates or use macros or inline functions from this file, or you compile
  27 // this file and link it with other files to produce an executable, this
  28 // file does not by itself cause the resulting executable to be covered by
  29 // the GNU General Public License.  This exception does not however
  30 // invalidate any other reasons why the executable file might be covered by
  31 // the GNU General Public License.
  32
  33 /** @file exception
  34  *  This is a Standard C++ Library header.
  35  */
  36
  37 #ifndef __EXCEPTION__
  38 #define __EXCEPTION__
  39
  40 #pragma GCC visibility push(default)
  41
  42 #include <bits/c++config.h>
  43
  44 extern "C++" {
  45
  46 namespace std
  47 {
  48   /**
  49    *  @brief Base class for all library exceptions.
  50    *
  51    *  This is the base class for all exceptions thrown by the standard
  52    *  library, and by certain language expressions.  You are free to derive
  53    *  your own %exception classes, or use a different hierarchy, or to
  54    *  throw non-class data (e.g., fundamental types).
  55    */
  56   class exception
  57   {
  58   public:
  59     exception() throw() { }
  60     virtual ~exception() throw();
  61
  62     /** Returns a C-style character string describing the general cause
  63      *  of the current error.  */
  64     virtual const char* what() const throw();
  65   };
  66
  67   /** If an %exception is thrown which is not listed in a function's
  68    *  %exception specification, one of these may be thrown.  */
  69   class bad_exception : public exception
  70   {
  71   public:
  72     bad_exception() throw() { }
  73
  74     // This declaration is not useless:
  75     // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118
  76     virtual ~bad_exception() throw();
  77
  78     // See comment in eh_exception.cc.
  79     virtual const char* what() const throw();
  80   };
  81
  82   /// If you write a replacement %terminate handler, it must be of this type.
  83   typedef void (*terminate_handler) ();
  84
  85   /// If you write a replacement %unexpected handler, it must be of this type.
  86   typedef void (*unexpected_handler) ();
  87
  88   /// Takes a new handler function as an argument, returns the old function.
  89   terminate_handler set_terminate(terminate_handler) throw();
  90
  91   /** The runtime will call this function if %exception handling must be
  92    *  abandoned for any reason.  It can also be called by the user.  */
  93   void terminate() __attribute__ ((__noreturn__));
  94
  95   /// Takes a new handler function as an argument, returns the old function.
  96   unexpected_handler set_unexpected(unexpected_handler) throw();
  97
  98   /** The runtime will call this function if an %exception is thrown which
  99    *  violates the function's %exception specification.  */
 100   void unexpected() __attribute__ ((__noreturn__));
 101
 102   /** [18.6.4]/1:  "Returns true after completing evaluation of a
 103    *  throw-expression until either completing initialization of the
 104    *  exception-declaration in the matching handler or entering @c unexpected()
 105    *  due to the throw; or after entering @c terminate() for any reason
 106    *  other than an explicit call to @c terminate().  [Note: This includes
 107    *  stack unwinding [15.2].  end note]"
 108    *
 109    *  2:  "When @c uncaught_exception() is true, throwing an %exception can
 110    *  result in a call of @c terminate() (15.5.1)."
 111    */
 112   bool uncaught_exception() throw();
 113
 114 } // namespace std
 115
 116 _GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
 117
 118   /** A replacement for the standard terminate_handler which prints more
 119       information about the terminating exception (if any) on stderr.  Call
 120       @code
 121         std::set_terminate (__gnu_cxx::__verbose_terminate_handler)
 122       @endcode
 123       to use.  For more info, see
 124       http://gcc.gnu.org/onlinedocs/libstdc++/19_diagnostics/howto.html#4
 125
 126       In 3.4 and later, this is on by default.
 127   */
 128   void __verbose_terminate_handler ();
 129
 130 _GLIBCXX_END_NAMESPACE
 131
 132 } // extern "C++"
 133
 134 #pragma GCC visibility pop
 135
 136 #ifdef __GXX_EXPERIMENTAL_CXX0X__
 137 #include <exception_ptr.h>
 138 #endif
 139
 140 #endif