1 // Exception Handling support header (exception_ptr class) for -*- C++ -*-
2
3 // Copyright (C) 2008-2013 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 ATOMIC_INT_LOCK_FREE < 2
40 # error This platform does not support exception propagation.
41 #endif
42
43 extern "C++" {
44
45 namespace std
46 {
47 class type_info;
48
49 /**
50 * @addtogroup exceptions
51 * @{
52 */
53 namespace __exception_ptr
54 {
55 class exception_ptr;
56 }
57
58 using __exception_ptr::exception_ptr;
59
60 /** Obtain an exception_ptr to the currently handled exception. If there
61 * is none, or the currently handled exception is foreign, return the null
62 * value.
63 */
64 exception_ptr current_exception() _GLIBCXX_USE_NOEXCEPT;
65
66 /// Throw the object pointed to by the exception_ptr.
67 void rethrow_exception(exception_ptr) __attribute__ ((__noreturn__));
68
69 namespace __exception_ptr
70 {
71 /**
72 * @brief An opaque pointer to an arbitrary exception.
73 * @ingroup exceptions
74 */
75 class exception_ptr
76 {
77 void* _M_exception_object;
78
79 explicit exception_ptr(void* __e) _GLIBCXX_USE_NOEXCEPT;
80
81 void _M_addref() _GLIBCXX_USE_NOEXCEPT;
82 void _M_release() _GLIBCXX_USE_NOEXCEPT;
83
84 void *_M_get() const _GLIBCXX_NOEXCEPT __attribute__ ((__pure__));
85
86 friend exception_ptr std::current_exception() _GLIBCXX_USE_NOEXCEPT;
87 friend void std::rethrow_exception(exception_ptr);
88
89 public:
90 exception_ptr() _GLIBCXX_USE_NOEXCEPT;
91
92 exception_ptr(const exception_ptr&) _GLIBCXX_USE_NOEXCEPT;
93
94 #if __cplusplus >= 201103L
95 exception_ptr(nullptr_t) noexcept
96 : _M_exception_object(0)
97 { }
98
99 exception_ptr(exception_ptr&& __o) noexcept
100 : _M_exception_object(__o._M_exception_object)
101 { __o._M_exception_object = 0; }
102 #endif
103
104 #if (__cplusplus < 201103L) || defined (_GLIBCXX_EH_PTR_COMPAT)
105 typedef void (exception_ptr::*__safe_bool)();
106
107 // For construction from nullptr or 0.
108 exception_ptr(__safe_bool) _GLIBCXX_USE_NOEXCEPT;
109 #endif
110
111 exception_ptr&
112 operator=(const exception_ptr&) _GLIBCXX_USE_NOEXCEPT;
113
114 #if __cplusplus >= 201103L
115 exception_ptr&
116 operator=(exception_ptr&& __o) noexcept
117 {
118 exception_ptr(static_cast<exception_ptr&&>(__o)).swap(*this);
119 return *this;
120 }
121 #endif
122
123 ~exception_ptr() _GLIBCXX_USE_NOEXCEPT;
124
125 void
126 swap(exception_ptr&) _GLIBCXX_USE_NOEXCEPT;
127
128 #ifdef _GLIBCXX_EH_PTR_COMPAT
129 // Retained for compatibility with CXXABI_1.3.
130 void _M_safe_bool_dummy() _GLIBCXX_USE_NOEXCEPT
131 __attribute__ ((__const__));
132 bool operator!() const _GLIBCXX_USE_NOEXCEPT
133 __attribute__ ((__pure__));
134 operator __safe_bool() const _GLIBCXX_USE_NOEXCEPT;
135 #endif
136
137 #if __cplusplus >= 201103L
138 explicit operator bool() const
139 { return _M_exception_object; }
140 #endif
141
142 friend bool
143 operator==(const exception_ptr&, const exception_ptr&)
144 _GLIBCXX_USE_NOEXCEPT __attribute__ ((__pure__));
145
146 const class std::type_info*
147 __cxa_exception_type() const _GLIBCXX_USE_NOEXCEPT
148 __attribute__ ((__pure__));
149 };
150
151 bool
152 operator==(const exception_ptr&, const exception_ptr&)
153 _GLIBCXX_USE_NOEXCEPT __attribute__ ((__pure__));
154
155 bool
156 operator!=(const exception_ptr&, const exception_ptr&)
157 _GLIBCXX_USE_NOEXCEPT __attribute__ ((__pure__));
158
159 inline void
160 swap(exception_ptr& __lhs, exception_ptr& __rhs)
161 { __lhs.swap(__rhs); }
162
163 } // namespace __exception_ptr
164
165
166 /// Obtain an exception_ptr pointing to a copy of the supplied object.
167 template<typename _Ex>
168 exception_ptr
169 copy_exception(_Ex __ex) _GLIBCXX_USE_NOEXCEPT
170 {
171 __try
172 {
173 #ifdef __EXCEPTIONS
174 throw __ex;
175 #endif
176 }
177 __catch(...)
178 {
179 return current_exception();
180 }
181 }
182
183 // _GLIBCXX_RESOLVE_LIB_DEFECTS
184 // 1130. copy_exception name misleading
185 /// Obtain an exception_ptr pointing to a copy of the supplied object.
186 template<typename _Ex>
187 exception_ptr
188 make_exception_ptr(_Ex __ex) _GLIBCXX_USE_NOEXCEPT
189 { return std::copy_exception<_Ex>(__ex); }
190
191 // @} group exceptions
192 } // namespace std
193
194 } // extern "C++"
195
196 #pragma GCC visibility pop
197
198 #endif
199