libstdc++-v3/libsupc++/exception

   1 // Exception Handling support header for -*- C++ -*-
   2
   3 // Copyright (C) 1995-2013 Free Software Foundation, Inc.
   4 //
   5 // This file is part of GCC.
   6 //
   7 // GCC is free software; you can redistribute it and/or modify
   8 // it under the terms of the GNU General Public License as published by
   9 // the Free Software Foundation; either version 3, or (at your option)
  10 // any later version.
  11 //
  12 // GCC is distributed in the hope that it will be useful,
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 // GNU General Public License for more details.
  16 //
  17 // Under Section 7 of GPL version 3, you are granted additional
  18 // permissions described in the GCC Runtime Library Exception, version
  19 // 3.1, as published by the Free Software Foundation.
  20
  21 // You should have received a copy of the GNU General Public License and
  22 // a copy of the GCC Runtime Library Exception along with this program;
  23 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  24 // <http://www.gnu.org/licenses/>.
  25
  26 /** @file exception
  27  *  This is a Standard C++ Library header.
  28  */
  29
  30 #ifndef __EXCEPTION__
  31 #define __EXCEPTION__
  32
  33 #pragma GCC system_header
  34
  35 #pragma GCC visibility push(default)
  36
  37 #include <bits/c++config.h>
  38 #include <bits/atomic_lockfree_defines.h>
  39
  40 extern "C++" {
  41
  42 namespace std
  43 {
  44   /**
  45    * @defgroup exceptions Exceptions
  46    * @ingroup diagnostics
  47    *
  48    * Classes and functions for reporting errors via exception classes.
  49    * @{
  50    */
  51
  52   /**
  53    *  @brief Base class for all library exceptions.
  54    *
  55    *  This is the base class for all exceptions thrown by the standard
  56    *  library, and by certain language expressions.  You are free to derive
  57    *  your own %exception classes, or use a different hierarchy, or to
  58    *  throw non-class data (e.g., fundamental types).
  59    */
  60   class exception
  61   {
  62   public:
  63     exception() _GLIBCXX_USE_NOEXCEPT { }
  64     virtual ~exception() _GLIBCXX_USE_NOEXCEPT;
  65
  66     /** Returns a C-style character string describing the general cause
  67      *  of the current error.  */
  68     virtual const char* what() const _GLIBCXX_USE_NOEXCEPT;
  69   };
  70
  71   /** If an %exception is thrown which is not listed in a function's
  72    *  %exception specification, one of these may be thrown.  */
  73   class bad_exception : public exception
  74   {
  75   public:
  76     bad_exception() _GLIBCXX_USE_NOEXCEPT { }
  77
  78     // This declaration is not useless:
  79     // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118
  80     virtual ~bad_exception() _GLIBCXX_USE_NOEXCEPT;
  81
  82     // See comment in eh_exception.cc.
  83     virtual const char* what() const _GLIBCXX_USE_NOEXCEPT;
  84   };
  85
  86   /// If you write a replacement %terminate handler, it must be of this type.
  87   typedef void (*terminate_handler) ();
  88
  89   /// If you write a replacement %unexpected handler, it must be of this type.
  90   typedef void (*unexpected_handler) ();
  91
  92   /// Takes a new handler function as an argument, returns the old function.
  93   terminate_handler set_terminate(terminate_handler) _GLIBCXX_USE_NOEXCEPT;
  94
  95 #if __cplusplus >= 201103L
  96   /// Return the current terminate handler.
  97   terminate_handler get_terminate() noexcept;
  98 #endif
  99
 100   /** The runtime will call this function if %exception handling must be
 101    *  abandoned for any reason.  It can also be called by the user.  */
 102   void terminate() _GLIBCXX_USE_NOEXCEPT __attribute__ ((__noreturn__));
 103
 104   /// Takes a new handler function as an argument, returns the old function.
 105   unexpected_handler set_unexpected(unexpected_handler) _GLIBCXX_USE_NOEXCEPT;
 106
 107 #if __cplusplus >= 201103L
 108   /// Return the current unexpected handler.
 109   unexpected_handler get_unexpected() noexcept;
 110 #endif
 111
 112   /** The runtime will call this function if an %exception is thrown which
 113    *  violates the function's %exception specification.  */
 114   void unexpected() __attribute__ ((__noreturn__));
 115
 116   /** [18.6.4]/1:  'Returns true after completing evaluation of a
 117    *  throw-expression until either completing initialization of the
 118    *  exception-declaration in the matching handler or entering @c unexpected()
 119    *  due to the throw; or after entering @c terminate() for any reason
 120    *  other than an explicit call to @c terminate().  [Note: This includes
 121    *  stack unwinding [15.2].  end note]'
 122    *
 123    *  2: 'When @c uncaught_exception() is true, throwing an
 124    *  %exception can result in a call of @c terminate()
 125    *  (15.5.1).'
 126    */
 127   bool uncaught_exception() _GLIBCXX_USE_NOEXCEPT __attribute__ ((__pure__));
 128
 129   // @} group exceptions
 130 } // namespace std
 131
 132 namespace __gnu_cxx
 133 {
 134 _GLIBCXX_BEGIN_NAMESPACE_VERSION
 135
 136   /**
 137    *  @brief A replacement for the standard terminate_handler which
 138    *  prints more information about the terminating exception (if any)
 139    *  on stderr.
 140    *
 141    *  @ingroup exceptions
 142    *
 143    *  Call
 144    *   @code
 145    *     std::set_terminate(__gnu_cxx::__verbose_terminate_handler)
 146    *   @endcode
 147    *  to use.  For more info, see
 148    *  http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt02ch06s02.html
 149    *
 150    *  In 3.4 and later, this is on by default.
 151    */
 152   void __verbose_terminate_handler();
 153
 154 _GLIBCXX_END_NAMESPACE_VERSION
 155 } // namespace
 156
 157 } // extern "C++"
 158
 159 #pragma GCC visibility pop
 160
 161 #if (__cplusplus >= 201103L) && (ATOMIC_INT_LOCK_FREE > 1)
 162 #include <bits/exception_ptr.h>
 163 #include <bits/nested_exception.h>
 164 #endif
 165
 166 #endif