libstdc++
exception_ptr.h
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1 // Exception Handling support header (exception_ptr class) for -*- C++ -*-
2 
3 // Copyright (C) 2008, 2009, 2010, 2011 Free Software Foundation
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 bits/exception_ptr.h
27  * This is an internal header file, included by other library headers.
28  * Do not attempt to use it directly. @headername{exception}
29  */
30 
31 #ifndef _EXCEPTION_PTR_H
32 #define _EXCEPTION_PTR_H
33 
34 #pragma GCC visibility push(default)
35 
36 #include <bits/c++config.h>
37 #include <bits/exception_defines.h>
38 
39 #if !defined(_GLIBCXX_ATOMIC_BUILTINS_4)
40 # error This platform does not support exception propagation.
41 #endif
42 
43 extern "C++" {
44 
45 namespace std
46 {
47  /**
48  * @addtogroup exceptions
49  * @{
50  */
51  namespace __exception_ptr
52  {
53  class exception_ptr;
54  }
55 
56  using __exception_ptr::exception_ptr;
57 
58  /** Obtain an exception_ptr to the currently handled exception. If there
59  * is none, or the currently handled exception is foreign, return the null
60  * value.
61  */
62  exception_ptr current_exception() throw();
63 
64  /// Throw the object pointed to by the exception_ptr.
65  void rethrow_exception(exception_ptr) __attribute__ ((__noreturn__));
66 
67  namespace __exception_ptr
68  {
69  /**
70  * @brief An opaque pointer to an arbitrary exception.
71  * @ingroup exceptions
72  */
74  {
75  void* _M_exception_object;
76 
77  explicit exception_ptr(void* __e) throw();
78 
79  void _M_addref() throw();
80  void _M_release() throw();
81 
82  void *_M_get() const throw() __attribute__ ((__pure__));
83 
84  friend exception_ptr std::current_exception() throw();
86 
87  public:
88  exception_ptr() throw();
89 
90  exception_ptr(const exception_ptr&) throw();
91 
92 #ifdef __GXX_EXPERIMENTAL_CXX0X__
93  exception_ptr(nullptr_t) throw()
94  : _M_exception_object(0)
95  { }
96 
97  exception_ptr(exception_ptr&& __o) throw()
98  : _M_exception_object(__o._M_exception_object)
99  { __o._M_exception_object = 0; }
100 #else
101  typedef void (exception_ptr::*__safe_bool)();
102 
103  // For construction from nullptr or 0.
104  exception_ptr(__safe_bool) throw();
105 #endif
106 
107  exception_ptr&
108  operator=(const exception_ptr&) throw();
109 
110 #ifdef __GXX_EXPERIMENTAL_CXX0X__
111  exception_ptr&
112  operator=(exception_ptr&& __o) throw()
113  {
114  exception_ptr(static_cast<exception_ptr&&>(__o)).swap(*this);
115  return *this;
116  }
117 #endif
118 
119  ~exception_ptr() throw();
120 
121  void
122  swap(exception_ptr&) throw();
123 
124 #ifdef _GLIBCXX_EH_PTR_COMPAT
125  // Retained for compatibility with CXXABI_1.3.
126  void _M_safe_bool_dummy() throw() __attribute__ ((__const__));
127  bool operator!() const throw() __attribute__ ((__pure__));
128  operator __safe_bool() const throw();
129 #endif
130 
131 #ifdef __GXX_EXPERIMENTAL_CXX0X__
132  explicit operator bool() const
133  { return _M_exception_object; }
134 #endif
135 
136  friend bool
137  operator==(const exception_ptr&, const exception_ptr&) throw()
138  __attribute__ ((__pure__));
139 
140  const class type_info*
141  __cxa_exception_type() const throw() __attribute__ ((__pure__));
142  };
143 
144  bool
145  operator==(const exception_ptr&, const exception_ptr&) throw()
146  __attribute__ ((__pure__));
147 
148  bool
149  operator!=(const exception_ptr&, const exception_ptr&) throw()
150  __attribute__ ((__pure__));
151 
152  inline void
153  swap(exception_ptr& __lhs, exception_ptr& __rhs)
154  { __lhs.swap(__rhs); }
155 
156  } // namespace __exception_ptr
157 
158 
159  /// Obtain an exception_ptr pointing to a copy of the supplied object.
160  template<typename _Ex>
161  exception_ptr
162  copy_exception(_Ex __ex) throw()
163  {
164  __try
165  {
166 #ifdef __EXCEPTIONS
167  throw __ex;
168 #endif
169  }
170  __catch(...)
171  {
172  return current_exception();
173  }
174  }
175 
176  // _GLIBCXX_RESOLVE_LIB_DEFECTS
177  // 1130. copy_exception name misleading
178  /// Obtain an exception_ptr pointing to a copy of the supplied object.
179  template<typename _Ex>
180  exception_ptr
181  make_exception_ptr(_Ex __ex) throw()
182  { return std::copy_exception<_Ex>(__ex); }
183 
184  // @} group exceptions
185 } // namespace std
186 
187 } // extern "C++"
188 
189 #pragma GCC visibility pop
190 
191 #endif
exception_ptr current_exception()
Part of RTTI.
Definition: typeinfo:91
exception_ptr make_exception_ptr(_Ex __ex)
Obtain an exception_ptr pointing to a copy of the supplied object.
exception_ptr copy_exception(_Ex __ex)
Obtain an exception_ptr pointing to a copy of the supplied object.
void rethrow_exception(exception_ptr) __attribute__((__noreturn__))
Throw the object pointed to by the exception_ptr.
An opaque pointer to an arbitrary exception.
Definition: exception_ptr.h:73