libstdc++
exception
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00001 // Exception Handling support header for -*- C++ -*-
00002 
00003 // Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003,
00004 // 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
00005 // Free Software Foundation
00006 //
00007 // This file is part of GCC.
00008 //
00009 // GCC is free software; you can redistribute it and/or modify
00010 // it under the terms of the GNU General Public License as published by
00011 // the Free Software Foundation; either version 3, or (at your option)
00012 // any later version.
00013 //
00014 // GCC is distributed in the hope that it will be useful,
00015 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00016 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00017 // GNU General Public License for more details.
00018 //
00019 // Under Section 7 of GPL version 3, you are granted additional
00020 // permissions described in the GCC Runtime Library Exception, version
00021 // 3.1, as published by the Free Software Foundation.
00022 
00023 // You should have received a copy of the GNU General Public License and
00024 // a copy of the GCC Runtime Library Exception along with this program;
00025 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
00026 // <http://www.gnu.org/licenses/>.
00027 
00028 /** @file exception
00029  *  This is a Standard C++ Library header.
00030  */
00031 
00032 #ifndef __EXCEPTION__
00033 #define __EXCEPTION__
00034 
00035 #pragma GCC system_header
00036 
00037 #pragma GCC visibility push(default)
00038 
00039 #include <bits/c++config.h>
00040 
00041 extern "C++" {
00042 
00043 namespace std
00044 {
00045   /**
00046    * @defgroup exceptions Exceptions
00047    * @ingroup diagnostics
00048    *
00049    * Classes and functions for reporting errors via exception classes.
00050    * @{
00051    */
00052 
00053   /**
00054    *  @brief Base class for all library exceptions.
00055    *
00056    *  This is the base class for all exceptions thrown by the standard
00057    *  library, and by certain language expressions.  You are free to derive
00058    *  your own %exception classes, or use a different hierarchy, or to
00059    *  throw non-class data (e.g., fundamental types).
00060    */
00061   class exception
00062   {
00063   public:
00064     exception() throw() { }
00065     virtual ~exception() throw();
00066 
00067     /** Returns a C-style character string describing the general cause
00068      *  of the current error.  */
00069     virtual const char* what() const throw();
00070   };
00071 
00072   /** If an %exception is thrown which is not listed in a function's
00073    *  %exception specification, one of these may be thrown.  */
00074   class bad_exception : public exception
00075   {
00076   public:
00077     bad_exception() throw() { }
00078 
00079     // This declaration is not useless:
00080     // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118
00081     virtual ~bad_exception() throw();
00082 
00083     // See comment in eh_exception.cc.
00084     virtual const char* what() const throw();
00085   };
00086 
00087   /// If you write a replacement %terminate handler, it must be of this type.
00088   typedef void (*terminate_handler) ();
00089 
00090   /// If you write a replacement %unexpected handler, it must be of this type.
00091   typedef void (*unexpected_handler) ();
00092 
00093   /// Takes a new handler function as an argument, returns the old function.
00094   terminate_handler set_terminate(terminate_handler) throw();
00095 
00096   /** The runtime will call this function if %exception handling must be
00097    *  abandoned for any reason.  It can also be called by the user.  */
00098   void terminate() throw() __attribute__ ((__noreturn__));
00099 
00100   /// Takes a new handler function as an argument, returns the old function.
00101   unexpected_handler set_unexpected(unexpected_handler) throw();
00102 
00103   /** The runtime will call this function if an %exception is thrown which
00104    *  violates the function's %exception specification.  */
00105   void unexpected() __attribute__ ((__noreturn__));
00106 
00107   /** [18.6.4]/1:  'Returns true after completing evaluation of a
00108    *  throw-expression until either completing initialization of the
00109    *  exception-declaration in the matching handler or entering @c unexpected()
00110    *  due to the throw; or after entering @c terminate() for any reason
00111    *  other than an explicit call to @c terminate().  [Note: This includes
00112    *  stack unwinding [15.2].  end note]'
00113    *
00114    *  2: 'When @c uncaught_exception() is true, throwing an
00115    *  %exception can result in a call of @c terminate()
00116    *  (15.5.1).'
00117    */
00118   bool uncaught_exception() throw() __attribute__ ((__pure__));
00119 
00120   // @} group exceptions
00121 } // namespace std
00122 
00123 namespace __gnu_cxx
00124 {
00125 _GLIBCXX_BEGIN_NAMESPACE_VERSION
00126 
00127   /**
00128    *  @brief A replacement for the standard terminate_handler which
00129    *  prints more information about the terminating exception (if any)
00130    *  on stderr.
00131    *
00132    *  @ingroup exceptions
00133    *
00134    *  Call
00135    *   @code
00136    *     std::set_terminate(__gnu_cxx::__verbose_terminate_handler)
00137    *   @endcode
00138    *  to use.  For more info, see
00139    *  http://gcc.gnu.org/onlinedocs/libstdc++/manual/bk01pt02ch06s02.html
00140    *
00141    *  In 3.4 and later, this is on by default.
00142    */
00143   void __verbose_terminate_handler();
00144 
00145 _GLIBCXX_END_NAMESPACE_VERSION
00146 } // namespace
00147 
00148 } // extern "C++"
00149 
00150 #pragma GCC visibility pop
00151 
00152 #if (defined(__GXX_EXPERIMENTAL_CXX0X__) \
00153      && defined(_GLIBCXX_ATOMIC_BUILTINS_4))
00154 #include <bits/exception_ptr.h>
00155 #include <bits/nested_exception.h>
00156 #endif
00157 
00158 #endif