gcc/libstdc++-v3/libsupc++/exception
Phil Edwards bad38757c3 exception: Add comment (mistakenly skipped).
2002-12-26  Phil Edwards  <pme@gcc.gnu.org>

	* libsupc++/exception:  Add comment (mistakenly skipped).

From-SVN: r60534
2002-12-27 00:23:20 +00:00

121 lines
4.5 KiB
C++

// Exception Handling support header for -*- C++ -*-
// Copyright (C) 1995, 1996, 1997, 1998, 2000, 2001, 2002
// Free Software Foundation
//
// This file is part of GNU CC.
//
// GNU CC is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 2, or (at your option)
// any later version.
//
// GNU CC is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with GNU CC; see the file COPYING. If not, write to
// the Free Software Foundation, 59 Temple Place - Suite 330,
// Boston, MA 02111-1307, USA.
// As a special exception, you may use this file as part of a free software
// library without restriction. Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License. This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.
/** @file exception
* This header defines several types and functions relating to the
* handling of exceptions in a C++ program.
*/
#ifndef __EXCEPTION__
#define __EXCEPTION__
extern "C++" {
namespace std
{
/**
* @brief Base class for all library exceptions.
*
* This is the base class for all exceptions thrown by the standard
* library, and by certain language expressions. You are free to derive
* your own %exception classes, or use a different hierarchy, or to
* throw non-class data (e.g., fundamental types).
*/
class exception
{
public:
exception() throw() { }
virtual ~exception() throw();
/** Returns a C-style character string describing the general cause
* of the current error. */
virtual const char* what() const throw();
};
/** If an %exception is thrown which is not listed in a function's
* %exception specification, one of these may be thrown. */
class bad_exception : public exception
{
public:
bad_exception() throw() { }
// This declaration is not useless:
// http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118
virtual ~bad_exception() throw();
};
/// If you write a replacement %terminate handler, it must be of this type.
typedef void (*terminate_handler) ();
/// If you write a replacement %unexpected handler, it must be of this type.
typedef void (*unexpected_handler) ();
/// Takes a new handler function as an argument, returns the old function.
terminate_handler set_terminate(terminate_handler) throw();
/** The runtime will call this function if %exception handling must be
* abandoned for any reason. It can also be called by the user. */
void terminate() __attribute__ ((__noreturn__));
/// Takes a new handler function as an argument, returns the old function.
unexpected_handler set_unexpected(unexpected_handler) throw();
/** The runtime will call this function if an %exception is thrown which
* violates the function's %exception specification. */
void unexpected() __attribute__ ((__noreturn__));
/** [18.6.4]/1: "Returns true after completing evaluation of a
* throw-expression until either completing initialization of the
* exception-declaration in the matching handler or entering @c unexpected()
* due to the throw; or after entering @c terminate() for any reason
* other than an explicit call to @c terminate(). [Note: This includes
* stack unwinding [15.2]. end note]"
*
* 2: "When @c uncaught_exception() is true, throwing an %exception can
* result in a call of @c terminate() (15.5.1)."
*/
bool uncaught_exception() throw();
} // namespace std
namespace __gnu_cxx
{
/** A replacement for the standard terminate_handler which prints more
information about the terminating exception (if any) on stderr. Call
@code
std::set_terminate (__gnu_cxx::__verbose_terminate_handler)
@endcode
to use. For more info, see
http://gcc.gnu.org/onlinedocs/libstdc++/19_diagnostics/howto.html#4
In 3.4 and later, this is on by default.
*/
void __verbose_terminate_handler ();
} // namespace __gnu_cxx
} // extern "C++"
#endif