libstdc++
exception_ptr.h
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1 // Exception Handling support header (exception_ptr class) for -*- C++ -*-
2 
3 // Copyright (C) 2008-2016 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 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(__ARM_EABI__) && !defined(__ARM_PCS_VFP))
40 #if ATOMIC_INT_LOCK_FREE < 2
41 # error This platform does not support exception propagation.
42 #endif
43 #endif
44 
45 extern "C++" {
46 
47 namespace std
48 {
49  class type_info;
50 
51  /**
52  * @addtogroup exceptions
53  * @{
54  */
55  namespace __exception_ptr
56  {
57  class exception_ptr;
58  }
59 
60  using __exception_ptr::exception_ptr;
61 
62  /** Obtain an exception_ptr to the currently handled exception. If there
63  * is none, or the currently handled exception is foreign, return the null
64  * value.
65  */
66  exception_ptr current_exception() _GLIBCXX_USE_NOEXCEPT;
67 
68  /// Throw the object pointed to by the exception_ptr.
69  void rethrow_exception(exception_ptr) __attribute__ ((__noreturn__));
70 
71  namespace __exception_ptr
72  {
74 
75  /**
76  * @brief An opaque pointer to an arbitrary exception.
77  * @ingroup exceptions
78  */
80  {
81  void* _M_exception_object;
82 
83  explicit exception_ptr(void* __e) _GLIBCXX_USE_NOEXCEPT;
84 
85  void _M_addref() _GLIBCXX_USE_NOEXCEPT;
86  void _M_release() _GLIBCXX_USE_NOEXCEPT;
87 
88  void *_M_get() const _GLIBCXX_NOEXCEPT __attribute__ ((__pure__));
89 
90  friend exception_ptr std::current_exception() _GLIBCXX_USE_NOEXCEPT;
92 
93  public:
94  exception_ptr() _GLIBCXX_USE_NOEXCEPT;
95 
96  exception_ptr(const exception_ptr&) _GLIBCXX_USE_NOEXCEPT;
97 
98 #if __cplusplus >= 201103L
99  exception_ptr(nullptr_t) noexcept
100  : _M_exception_object(0)
101  { }
102 
103  exception_ptr(exception_ptr&& __o) noexcept
104  : _M_exception_object(__o._M_exception_object)
105  { __o._M_exception_object = 0; }
106 #endif
107 
108 #if (__cplusplus < 201103L) || defined (_GLIBCXX_EH_PTR_COMPAT)
109  typedef void (exception_ptr::*__safe_bool)();
110 
111  // For construction from nullptr or 0.
112  exception_ptr(__safe_bool) _GLIBCXX_USE_NOEXCEPT;
113 #endif
114 
115  exception_ptr&
116  operator=(const exception_ptr&) _GLIBCXX_USE_NOEXCEPT;
117 
118 #if __cplusplus >= 201103L
119  exception_ptr&
120  operator=(exception_ptr&& __o) noexcept
121  {
122  exception_ptr(static_cast<exception_ptr&&>(__o)).swap(*this);
123  return *this;
124  }
125 #endif
126 
127  ~exception_ptr() _GLIBCXX_USE_NOEXCEPT;
128 
129  void
130  swap(exception_ptr&) _GLIBCXX_USE_NOEXCEPT;
131 
132 #ifdef _GLIBCXX_EH_PTR_COMPAT
133  // Retained for compatibility with CXXABI_1.3.
134  void _M_safe_bool_dummy() _GLIBCXX_USE_NOEXCEPT
135  __attribute__ ((__const__));
136  bool operator!() const _GLIBCXX_USE_NOEXCEPT
137  __attribute__ ((__pure__));
138  operator __safe_bool() const _GLIBCXX_USE_NOEXCEPT;
139 #endif
140 
141 #if __cplusplus >= 201103L
142  explicit operator bool() const
143  { return _M_exception_object; }
144 #endif
145 
146  friend bool
147  operator==(const exception_ptr&, const exception_ptr&)
148  _GLIBCXX_USE_NOEXCEPT __attribute__ ((__pure__));
149 
150  const class std::type_info*
151  __cxa_exception_type() const _GLIBCXX_USE_NOEXCEPT
152  __attribute__ ((__pure__));
153  };
154 
155  bool
156  operator==(const exception_ptr&, const exception_ptr&)
157  _GLIBCXX_USE_NOEXCEPT __attribute__ ((__pure__));
158 
159  bool
160  operator!=(const exception_ptr&, const exception_ptr&)
161  _GLIBCXX_USE_NOEXCEPT __attribute__ ((__pure__));
162 
163  inline void
164  swap(exception_ptr& __lhs, exception_ptr& __rhs)
165  { __lhs.swap(__rhs); }
166 
167  } // namespace __exception_ptr
168 
169 
170  /// Obtain an exception_ptr pointing to a copy of the supplied object.
171  template<typename _Ex>
172  exception_ptr
173  make_exception_ptr(_Ex __ex) _GLIBCXX_USE_NOEXCEPT
174  {
175 #if __cpp_exceptions
176  try
177  {
178  throw __ex;
179  }
180  catch(...)
181  {
182  return current_exception();
183  }
184 #else
185  return exception_ptr();
186 #endif
187  }
188 
189  // _GLIBCXX_RESOLVE_LIB_DEFECTS
190  // 1130. copy_exception name misleading
191  /// Obtain an exception_ptr pointing to a copy of the supplied object.
192  /// This function is deprecated, use std::make_exception_ptr instead.
193  template<typename _Ex>
194  exception_ptr
195  copy_exception(_Ex __ex) _GLIBCXX_USE_NOEXCEPT _GLIBCXX_DEPRECATED;
196 
197  template<typename _Ex>
198  exception_ptr
199  copy_exception(_Ex __ex) _GLIBCXX_USE_NOEXCEPT
200  { return std::make_exception_ptr<_Ex>(__ex); }
201 
202  // @} group exceptions
203 } // namespace std
204 
205 } // extern "C++"
206 
207 #pragma GCC visibility pop
208 
209 #endif
An opaque pointer to an arbitrary exception.
Definition: exception_ptr.h:79
exception_ptr current_exception() noexcept
exception_ptr copy_exception(_Ex __ex) noexcept 1
Obtain an exception_ptr pointing to a copy of the supplied object. This function is deprecated...
void rethrow_exception(exception_ptr) __attribute__((__noreturn__))
Throw the object pointed to by the exception_ptr.
ISO C++ entities toplevel namespace is std.
Part of RTTI.
Definition: typeinfo:88
exception_ptr make_exception_ptr(_Ex __ex) noexcept
Obtain an exception_ptr pointing to a copy of the supplied object.