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, 2009, 2010, 2011
   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 3, 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 // Under Section 7 of GPL version 3, you are granted additional
  20 // permissions described in the GCC Runtime Library Exception, version
  21 // 3.1, as published by the Free Software Foundation.
  22
  23 // You should have received a copy of the GNU General Public License and
  24 // a copy of the GCC Runtime Library Exception along with this program;
  25 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  26 // <http://www.gnu.org/licenses/>.
  27
  28 /** @file exception
  29  *  This is a Standard C++ Library header.
  30  */
  31
  32 #ifndef __EXCEPTION__
  33 #define __EXCEPTION__
  34
  35 #pragma GCC system_header
  36
  37 #pragma GCC visibility push(default)
  38
  39 #include <bits/c++config.h>
  40
  41 extern "C++" {
  42
  43 namespace std
  44 {
  45   /**
  46    * @defgroup exceptions Exceptions
  47    * @ingroup diagnostics
  48    *
  49    * Classes and functions for reporting errors via exception classes.
  50    * @{
  51    */
  52
  53   /**
  54    *  @brief Base class for all library exceptions.
  55    *
  56    *  This is the base class for all exceptions thrown by the standard
  57    *  library, and by certain language expressions.  You are free to derive
  58    *  your own %exception classes, or use a different hierarchy, or to
  59    *  throw non-class data (e.g., fundamental types).
  60    */
  61   class exception
  62   {
  63   public:
  64     exception() throw() { }
  65     virtual ~exception() throw();
  66
  67     /** Returns a C-style character string describing the general cause
  68      *  of the current error.  */
  69     virtual const char* what() const throw();
  70   };
  71
  72   /** If an %exception is thrown which is not listed in a function's
  73    *  %exception specification, one of these may be thrown.  */
  74   class bad_exception : public exception
  75   {
  76   public:
  77     bad_exception() throw() { }
  78
  79     // This declaration is not useless:
  80     // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118
  81     virtual ~bad_exception() throw();
  82
  83     // See comment in eh_exception.cc.
  84     virtual const char* what() const throw();
  85   };
  86
  87   /// If you write a replacement %terminate handler, it must be of this type.
  88   typedef void (*terminate_handler) ();
  89
  90   /// If you write a replacement %unexpected handler, it must be of this type.
  91   typedef void (*unexpected_handler) ();
  92
  93   /// Takes a new handler function as an argument, returns the old function.
  94   terminate_handler set_terminate(terminate_handler) throw();
  95
  96   /** The runtime will call this function if %exception handling must be
  97    *  abandoned for any reason.  It can also be called by the user.  */
  98   void terminate() throw() __attribute__ ((__noreturn__));
  99
 100   /// Takes a new handler function as an argument, returns the old function.
 101   unexpected_handler set_unexpected(unexpected_handler) throw();
 102
 103   /** The runtime will call this function if an %exception is thrown which
 104    *  violates the function's %exception specification.  */
 105   void unexpected() __attribute__ ((__noreturn__));
 106
 107   /** [18.6.4]/1:  'Returns true after completing evaluation of a
 108    *  throw-expression until either completing initialization of the
 109    *  exception-declaration in the matching handler or entering @c unexpected()
 110    *  due to the throw; or after entering @c terminate() for any reason
 111    *  other than an explicit call to @c terminate().  [Note: This includes
 112    *  stack unwinding [15.2].  end note]'
 113    *
 114    *  2: 'When @c uncaught_exception() is true, throwing an
 115    *  %exception can result in a call of @c terminate()
 116    *  (15.5.1).'
 117    */
 118   bool uncaught_exception() throw() __attribute__ ((__pure__));
 119
 120   // @} group exceptions
 121 } // namespace std
 122
 123 namespace __gnu_cxx
 124 {
 125 _GLIBCXX_BEGIN_NAMESPACE_VERSION
 126
 127   /**
 128    *  @brief A replacement for the standard terminate_handler which
 129    *  prints more information about the terminating exception (if any)
 130    *  on stderr.
 131    *
 132    *  @ingroup exceptions
 133    *
 134    *  Call
 135    *   @code
 136    *     std::set_terminate(__gnu_cxx::__verbose_terminate_handler)
 137    *   @endcode
 138    *  to use.  For more info, see
 139    *  http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt02ch06s02.html
 140    *
 141    *  In 3.4 and later, this is on by default.
 142    */
 143   void __verbose_terminate_handler();
 144
 145 _GLIBCXX_END_NAMESPACE_VERSION
 146 } // namespace
 147
 148 } // extern "C++"
 149
 150 #pragma GCC visibility pop
 151
 152 #if (defined(__GXX_EXPERIMENTAL_CXX0X__) \
 153      && defined(_GLIBCXX_ATOMIC_BUILTINS_4))
 154 #include <bits/exception_ptr.h>
 155 #include <bits/nested_exception.h>
 156 #endif
 157
 158 #endif