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
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 2, 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// You should have received a copy of the GNU General Public License
20// along with GCC; see the file COPYING.  If not, write to
21// the Free Software Foundation, 51 Franklin Street, Fifth Floor,
22// Boston, MA 02110-1301, USA.
23
24// As a special exception, you may use this file as part of a free software
25// library without restriction.  Specifically, if other files instantiate
26// templates or use macros or inline functions from this file, or you compile
27// this file and link it with other files to produce an executable, this
28// file does not by itself cause the resulting executable to be covered by
29// the GNU General Public License.  This exception does not however
30// invalidate any other reasons why the executable file might be covered by
31// the GNU General Public License.
32
33/** @file exception
34 *  This is a Standard C++ Library header.
35 */
36
37#ifndef __EXCEPTION__
38#define __EXCEPTION__
39
40#pragma GCC visibility push(default)
41
42#include <bits/c++config.h>
43
44extern "C++" {
45
46namespace std
47{
48  /**
49   *  @brief Base class for all library exceptions.
50   *
51   *  This is the base class for all exceptions thrown by the standard
52   *  library, and by certain language expressions.  You are free to derive
53   *  your own %exception classes, or use a different hierarchy, or to
54   *  throw non-class data (e.g., fundamental types).
55   */
56  class exception
57  {
58  public:
59    exception() throw() { }
60    virtual ~exception() throw();
61
62    /** Returns a C-style character string describing the general cause
63     *  of the current error.  */
64    virtual const char* what() const throw();
65  };
66
67  /** If an %exception is thrown which is not listed in a function's
68   *  %exception specification, one of these may be thrown.  */
69  class bad_exception : public exception
70  {
71  public:
72    bad_exception() throw() { }
73
74    // This declaration is not useless:
75    // http://gcc.gnu.org/onlinedocs/gcc-3.0.2/gcc_6.html#SEC118
76    virtual ~bad_exception() throw();
77
78    // See comment in eh_exception.cc.
79    virtual const char* what() const throw();
80  };
81
82  /// If you write a replacement %terminate handler, it must be of this type.
83  typedef void (*terminate_handler) ();
84
85  /// If you write a replacement %unexpected handler, it must be of this type.
86  typedef void (*unexpected_handler) ();
87
88  /// Takes a new handler function as an argument, returns the old function.
89  terminate_handler set_terminate(terminate_handler) throw();
90
91  /** The runtime will call this function if %exception handling must be
92   *  abandoned for any reason.  It can also be called by the user.  */
93  void terminate() __attribute__ ((__noreturn__));
94
95  /// Takes a new handler function as an argument, returns the old function.
96  unexpected_handler set_unexpected(unexpected_handler) throw();
97
98  /** The runtime will call this function if an %exception is thrown which
99   *  violates the function's %exception specification.  */
100  void unexpected() __attribute__ ((__noreturn__));
101
102  /** [18.6.4]/1:  "Returns true after completing evaluation of a
103   *  throw-expression until either completing initialization of the
104   *  exception-declaration in the matching handler or entering @c unexpected()
105   *  due to the throw; or after entering @c terminate() for any reason
106   *  other than an explicit call to @c terminate().  [Note: This includes
107   *  stack unwinding [15.2].  end note]"
108   *
109   *  2:  "When @c uncaught_exception() is true, throwing an %exception can
110   *  result in a call of @c terminate() (15.5.1)."
111   */
112  bool uncaught_exception() throw();
113} // namespace std
114
115_GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
116
117  /** A replacement for the standard terminate_handler which prints more
118      information about the terminating exception (if any) on stderr.  Call
119      @code
120        std::set_terminate (__gnu_cxx::__verbose_terminate_handler)
121      @endcode
122      to use.  For more info, see
123      http://gcc.gnu.org/onlinedocs/libstdc++/19_diagnostics/howto.html#4
124
125      In 3.4 and later, this is on by default.
126  */
127  void __verbose_terminate_handler ();
128
129_GLIBCXX_END_NAMESPACE
130
131} // extern "C++"
132
133#pragma GCC visibility pop
134
135#endif
136