1 | // <system_error> -*- C++ -*- |
2 | |
3 | // Copyright (C) 2007-2017 Free Software Foundation, Inc. |
4 | // |
5 | // This file is part of the GNU ISO C++ Library. This library is free |
6 | // software; you can redistribute it and/or modify it under the |
7 | // terms of the GNU General Public License as published by the |
8 | // Free Software Foundation; either version 3, or (at your option) |
9 | // any later version. |
10 | |
11 | // This library is distributed in the hope that it will be useful, |
12 | // but WITHOUT ANY WARRANTY; without even the implied warranty of |
13 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
14 | // GNU General Public License for more details. |
15 | |
16 | // Under Section 7 of GPL version 3, you are granted additional |
17 | // permissions described in the GCC Runtime Library Exception, version |
18 | // 3.1, as published by the Free Software Foundation. |
19 | |
20 | // You should have received a copy of the GNU General Public License and |
21 | // a copy of the GCC Runtime Library Exception along with this program; |
22 | // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
23 | // <http://www.gnu.org/licenses/>. |
24 | |
25 | /** @file include/system_error |
26 | * This is a Standard C++ Library header. |
27 | */ |
28 | |
29 | #ifndef _GLIBCXX_SYSTEM_ERROR |
30 | #define _GLIBCXX_SYSTEM_ERROR 1 |
31 | |
32 | #pragma GCC system_header |
33 | |
34 | #if __cplusplus < 201103L |
35 | # include <bits/c++0x_warning.h> |
36 | #else |
37 | |
38 | #include <bits/c++config.h> |
39 | #include <bits/error_constants.h> |
40 | #include <iosfwd> |
41 | #include <stdexcept> |
42 | |
43 | namespace std _GLIBCXX_VISIBILITY(default) |
44 | { |
45 | _GLIBCXX_BEGIN_NAMESPACE_VERSION |
46 | |
47 | class error_code; |
48 | class error_condition; |
49 | class system_error; |
50 | |
51 | /// is_error_code_enum |
52 | template<typename _Tp> |
53 | struct is_error_code_enum : public false_type { }; |
54 | |
55 | /// is_error_condition_enum |
56 | template<typename _Tp> |
57 | struct is_error_condition_enum : public false_type { }; |
58 | |
59 | template<> |
60 | struct is_error_condition_enum<errc> |
61 | : public true_type { }; |
62 | |
63 | #if __cplusplus > 201402L |
64 | template <typename _Tp> |
65 | inline constexpr bool is_error_code_enum_v = |
66 | is_error_code_enum<_Tp>::value; |
67 | template <typename _Tp> |
68 | inline constexpr bool is_error_condition_enum_v = |
69 | is_error_condition_enum<_Tp>::value; |
70 | #endif // C++17 |
71 | inline namespace _V2 { |
72 | |
73 | /// error_category |
74 | class error_category |
75 | { |
76 | public: |
77 | constexpr error_category() noexcept = default; |
78 | |
79 | virtual ~error_category(); |
80 | |
81 | error_category(const error_category&) = delete; |
82 | error_category& operator=(const error_category&) = delete; |
83 | |
84 | virtual const char* |
85 | name() const noexcept = 0; |
86 | |
87 | // We need two different virtual functions here, one returning a |
88 | // COW string and one returning an SSO string. Their positions in the |
89 | // vtable must be consistent for dynamic dispatch to work, but which one |
90 | // the name "message()" finds depends on which ABI the caller is using. |
91 | #if _GLIBCXX_USE_CXX11_ABI |
92 | private: |
93 | _GLIBCXX_DEFAULT_ABI_TAG |
94 | virtual __cow_string |
95 | _M_message(int) const; |
96 | |
97 | public: |
98 | _GLIBCXX_DEFAULT_ABI_TAG |
99 | virtual string |
100 | message(int) const = 0; |
101 | #else |
102 | virtual string |
103 | message(int) const = 0; |
104 | |
105 | private: |
106 | virtual __sso_string |
107 | _M_message(int) const; |
108 | #endif |
109 | |
110 | public: |
111 | virtual error_condition |
112 | default_error_condition(int __i) const noexcept; |
113 | |
114 | virtual bool |
115 | equivalent(int __i, const error_condition& __cond) const noexcept; |
116 | |
117 | virtual bool |
118 | equivalent(const error_code& __code, int __i) const noexcept; |
119 | |
120 | bool |
121 | operator<(const error_category& __other) const noexcept |
122 | { return less<const error_category*>()(this, &__other); } |
123 | |
124 | bool |
125 | operator==(const error_category& __other) const noexcept |
126 | { return this == &__other; } |
127 | |
128 | bool |
129 | operator!=(const error_category& __other) const noexcept |
130 | { return this != &__other; } |
131 | }; |
132 | |
133 | // DR 890. |
134 | _GLIBCXX_CONST const error_category& system_category() noexcept; |
135 | _GLIBCXX_CONST const error_category& generic_category() noexcept; |
136 | |
137 | } // end inline namespace |
138 | |
139 | error_code make_error_code(errc) noexcept; |
140 | |
141 | template<typename _Tp> |
142 | struct hash; |
143 | |
144 | /// error_code |
145 | // Implementation-specific error identification |
146 | struct error_code |
147 | { |
148 | error_code() noexcept |
149 | : _M_value(0), _M_cat(&system_category()) { } |
150 | |
151 | error_code(int __v, const error_category& __cat) noexcept |
152 | : _M_value(__v), _M_cat(&__cat) { } |
153 | |
154 | template<typename _ErrorCodeEnum, typename = typename |
155 | enable_if<is_error_code_enum<_ErrorCodeEnum>::value>::type> |
156 | error_code(_ErrorCodeEnum __e) noexcept |
157 | { *this = make_error_code(__e); } |
158 | |
159 | void |
160 | assign(int __v, const error_category& __cat) noexcept |
161 | { |
162 | _M_value = __v; |
163 | _M_cat = &__cat; |
164 | } |
165 | |
166 | void |
167 | clear() noexcept |
168 | { assign(0, system_category()); } |
169 | |
170 | // DR 804. |
171 | template<typename _ErrorCodeEnum> |
172 | typename enable_if<is_error_code_enum<_ErrorCodeEnum>::value, |
173 | error_code&>::type |
174 | operator=(_ErrorCodeEnum __e) noexcept |
175 | { return *this = make_error_code(__e); } |
176 | |
177 | int |
178 | value() const noexcept { return _M_value; } |
179 | |
180 | const error_category& |
181 | category() const noexcept { return *_M_cat; } |
182 | |
183 | error_condition |
184 | default_error_condition() const noexcept; |
185 | |
186 | _GLIBCXX_DEFAULT_ABI_TAG |
187 | string |
188 | message() const |
189 | { return category().message(value()); } |
190 | |
191 | explicit operator bool() const noexcept |
192 | { return _M_value != 0; } |
193 | |
194 | // DR 804. |
195 | private: |
196 | friend class hash<error_code>; |
197 | |
198 | int _M_value; |
199 | const error_category* _M_cat; |
200 | }; |
201 | |
202 | // 19.4.2.6 non-member functions |
203 | inline error_code |
204 | make_error_code(errc __e) noexcept |
205 | { return error_code(static_cast<int>(__e), generic_category()); } |
206 | |
207 | inline bool |
208 | operator<(const error_code& __lhs, const error_code& __rhs) noexcept |
209 | { |
210 | return (__lhs.category() < __rhs.category() |
211 | || (__lhs.category() == __rhs.category() |
212 | && __lhs.value() < __rhs.value())); |
213 | } |
214 | |
215 | template<typename _CharT, typename _Traits> |
216 | basic_ostream<_CharT, _Traits>& |
217 | operator<<(basic_ostream<_CharT, _Traits>& __os, const error_code& __e) |
218 | { return (__os << __e.category().name() << ':' << __e.value()); } |
219 | |
220 | error_condition make_error_condition(errc) noexcept; |
221 | |
222 | /// error_condition |
223 | // Portable error identification |
224 | struct error_condition |
225 | { |
226 | error_condition() noexcept |
227 | : _M_value(0), _M_cat(&generic_category()) { } |
228 | |
229 | error_condition(int __v, const error_category& __cat) noexcept |
230 | : _M_value(__v), _M_cat(&__cat) { } |
231 | |
232 | template<typename _ErrorConditionEnum, typename = typename |
233 | enable_if<is_error_condition_enum<_ErrorConditionEnum>::value>::type> |
234 | error_condition(_ErrorConditionEnum __e) noexcept |
235 | { *this = make_error_condition(__e); } |
236 | |
237 | void |
238 | assign(int __v, const error_category& __cat) noexcept |
239 | { |
240 | _M_value = __v; |
241 | _M_cat = &__cat; |
242 | } |
243 | |
244 | // DR 804. |
245 | template<typename _ErrorConditionEnum> |
246 | typename enable_if<is_error_condition_enum |
247 | <_ErrorConditionEnum>::value, error_condition&>::type |
248 | operator=(_ErrorConditionEnum __e) noexcept |
249 | { return *this = make_error_condition(__e); } |
250 | |
251 | void |
252 | clear() noexcept |
253 | { assign(0, generic_category()); } |
254 | |
255 | // 19.4.3.4 observers |
256 | int |
257 | value() const noexcept { return _M_value; } |
258 | |
259 | const error_category& |
260 | category() const noexcept { return *_M_cat; } |
261 | |
262 | _GLIBCXX_DEFAULT_ABI_TAG |
263 | string |
264 | message() const |
265 | { return category().message(value()); } |
266 | |
267 | explicit operator bool() const noexcept |
268 | { return _M_value != 0; } |
269 | |
270 | // DR 804. |
271 | private: |
272 | int _M_value; |
273 | const error_category* _M_cat; |
274 | }; |
275 | |
276 | // 19.4.3.6 non-member functions |
277 | inline error_condition |
278 | make_error_condition(errc __e) noexcept |
279 | { return error_condition(static_cast<int>(__e), generic_category()); } |
280 | |
281 | inline bool |
282 | operator<(const error_condition& __lhs, |
283 | const error_condition& __rhs) noexcept |
284 | { |
285 | return (__lhs.category() < __rhs.category() |
286 | || (__lhs.category() == __rhs.category() |
287 | && __lhs.value() < __rhs.value())); |
288 | } |
289 | |
290 | // 19.4.4 Comparison operators |
291 | inline bool |
292 | operator==(const error_code& __lhs, const error_code& __rhs) noexcept |
293 | { return (__lhs.category() == __rhs.category() |
294 | && __lhs.value() == __rhs.value()); } |
295 | |
296 | inline bool |
297 | operator==(const error_code& __lhs, const error_condition& __rhs) noexcept |
298 | { |
299 | return (__lhs.category().equivalent(__lhs.value(), __rhs) |
300 | || __rhs.category().equivalent(__lhs, __rhs.value())); |
301 | } |
302 | |
303 | inline bool |
304 | operator==(const error_condition& __lhs, const error_code& __rhs) noexcept |
305 | { |
306 | return (__rhs.category().equivalent(__rhs.value(), __lhs) |
307 | || __lhs.category().equivalent(__rhs, __lhs.value())); |
308 | } |
309 | |
310 | inline bool |
311 | operator==(const error_condition& __lhs, |
312 | const error_condition& __rhs) noexcept |
313 | { |
314 | return (__lhs.category() == __rhs.category() |
315 | && __lhs.value() == __rhs.value()); |
316 | } |
317 | |
318 | inline bool |
319 | operator!=(const error_code& __lhs, const error_code& __rhs) noexcept |
320 | { return !(__lhs == __rhs); } |
321 | |
322 | inline bool |
323 | operator!=(const error_code& __lhs, const error_condition& __rhs) noexcept |
324 | { return !(__lhs == __rhs); } |
325 | |
326 | inline bool |
327 | operator!=(const error_condition& __lhs, const error_code& __rhs) noexcept |
328 | { return !(__lhs == __rhs); } |
329 | |
330 | inline bool |
331 | operator!=(const error_condition& __lhs, |
332 | const error_condition& __rhs) noexcept |
333 | { return !(__lhs == __rhs); } |
334 | |
335 | |
336 | /** |
337 | * @brief Thrown to indicate error code of underlying system. |
338 | * |
339 | * @ingroup exceptions |
340 | */ |
341 | class system_error : public std::runtime_error |
342 | { |
343 | private: |
344 | error_code _M_code; |
345 | |
346 | public: |
347 | system_error(error_code __ec = error_code()) |
348 | : runtime_error(__ec.message()), _M_code(__ec) { } |
349 | |
350 | system_error(error_code __ec, const string& __what) |
351 | : runtime_error(__what + ": " + __ec.message()), _M_code(__ec) { } |
352 | |
353 | system_error(error_code __ec, const char* __what) |
354 | : runtime_error(__what + (": " + __ec.message())), _M_code(__ec) { } |
355 | |
356 | system_error(int __v, const error_category& __ecat, const char* __what) |
357 | : system_error(error_code(__v, __ecat), __what) { } |
358 | |
359 | system_error(int __v, const error_category& __ecat) |
360 | : runtime_error(error_code(__v, __ecat).message()), |
361 | _M_code(__v, __ecat) { } |
362 | |
363 | system_error(int __v, const error_category& __ecat, const string& __what) |
364 | : runtime_error(__what + ": " + error_code(__v, __ecat).message()), |
365 | _M_code(__v, __ecat) { } |
366 | |
367 | virtual ~system_error() noexcept; |
368 | |
369 | const error_code& |
370 | code() const noexcept { return _M_code; } |
371 | }; |
372 | |
373 | _GLIBCXX_END_NAMESPACE_VERSION |
374 | } // namespace |
375 | |
376 | #include <bits/functional_hash.h> |
377 | |
378 | namespace std _GLIBCXX_VISIBILITY(default) |
379 | { |
380 | _GLIBCXX_BEGIN_NAMESPACE_VERSION |
381 | |
382 | #ifndef _GLIBCXX_COMPATIBILITY_CXX0X |
383 | // DR 1182. |
384 | /// std::hash specialization for error_code. |
385 | template<> |
386 | struct hash<error_code> |
387 | : public __hash_base<size_t, error_code> |
388 | { |
389 | size_t |
390 | operator()(const error_code& __e) const noexcept |
391 | { |
392 | const size_t __tmp = std::_Hash_impl::hash(__e._M_value); |
393 | return std::_Hash_impl::__hash_combine(__e._M_cat, __tmp); |
394 | } |
395 | }; |
396 | #endif // _GLIBCXX_COMPATIBILITY_CXX0X |
397 | |
398 | #if __cplusplus > 201402L |
399 | // DR 2686. |
400 | /// std::hash specialization for error_condition. |
401 | template<> |
402 | struct hash<error_condition> |
403 | : public __hash_base<size_t, error_condition> |
404 | { |
405 | size_t |
406 | operator()(const error_condition& __e) const noexcept |
407 | { |
408 | const size_t __tmp = std::_Hash_impl::hash(__e.value()); |
409 | return std::_Hash_impl::__hash_combine(__e.category(), __tmp); |
410 | } |
411 | }; |
412 | #endif |
413 | |
414 | _GLIBCXX_END_NAMESPACE_VERSION |
415 | } // namespace |
416 | |
417 | #endif // C++11 |
418 | |
419 | #endif // _GLIBCXX_SYSTEM_ERROR |
420 | |