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