xref: /freebsd/contrib/llvm-project/libcxx/include/system_error (revision 0eae32dcef82f6f06de6419a0d623d7def0cc8f6) 
1// -*- C++ -*-
2//===----------------------------------------------------------------------===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef _LIBCPP_SYSTEM_ERROR
11#define _LIBCPP_SYSTEM_ERROR
12
13/*
14    system_error synopsis
15
16namespace std
17{
18
19class error_category
20{
21public:
22    virtual ~error_category() noexcept;
23
24    constexpr error_category();
25    error_category(const error_category&) = delete;
26    error_category& operator=(const error_category&) = delete;
27
28    virtual const char* name() const noexcept = 0;
29    virtual error_condition default_error_condition(int ev) const noexcept;
30    virtual bool equivalent(int code, const error_condition& condition) const noexcept;
31    virtual bool equivalent(const error_code& code, int condition) const noexcept;
32    virtual string message(int ev) const = 0;
33
34    bool operator==(const error_category& rhs) const noexcept;
35    bool operator!=(const error_category& rhs) const noexcept;
36    bool operator<(const error_category& rhs) const noexcept;
37};
38
39const error_category& generic_category() noexcept;
40const error_category& system_category() noexcept;
41
42template <class T> struct is_error_code_enum
43    : public false_type {};
44
45template <class T> struct is_error_condition_enum
46    : public false_type {};
47
48template <class _Tp>
49inline constexpr bool is_error_condition_enum_v = is_error_condition_enum<_Tp>::value; // C++17
50
51template <class _Tp>
52inline constexpr bool is_error_code_enum_v = is_error_code_enum<_Tp>::value; // C++17
53
54class error_code
55{
56public:
57    // constructors:
58    error_code() noexcept;
59    error_code(int val, const error_category& cat) noexcept;
60    template <class ErrorCodeEnum>
61        error_code(ErrorCodeEnum e) noexcept;
62
63    // modifiers:
64    void assign(int val, const error_category& cat) noexcept;
65    template <class ErrorCodeEnum>
66        error_code& operator=(ErrorCodeEnum e) noexcept;
67    void clear() noexcept;
68
69    // observers:
70    int value() const noexcept;
71    const error_category& category() const noexcept;
72    error_condition default_error_condition() const noexcept;
73    string message() const;
74    explicit operator bool() const noexcept;
75};
76
77// non-member functions:
78bool operator<(const error_code& lhs, const error_code& rhs) noexcept;
79template <class charT, class traits>
80    basic_ostream<charT,traits>&
81    operator<<(basic_ostream<charT,traits>& os, const error_code& ec);
82
83class error_condition
84{
85public:
86    // constructors:
87    error_condition() noexcept;
88    error_condition(int val, const error_category& cat) noexcept;
89    template <class ErrorConditionEnum>
90        error_condition(ErrorConditionEnum e) noexcept;
91
92    // modifiers:
93    void assign(int val, const error_category& cat) noexcept;
94    template <class ErrorConditionEnum>
95        error_condition& operator=(ErrorConditionEnum e) noexcept;
96    void clear() noexcept;
97
98    // observers:
99    int value() const noexcept;
100    const error_category& category() const noexcept;
101    string message() const noexcept;
102    explicit operator bool() const noexcept;
103};
104
105bool operator<(const error_condition& lhs, const error_condition& rhs) noexcept;
106
107class system_error
108    : public runtime_error
109{
110public:
111    system_error(error_code ec, const string& what_arg);
112    system_error(error_code ec, const char* what_arg);
113    system_error(error_code ec);
114    system_error(int ev, const error_category& ecat, const string& what_arg);
115    system_error(int ev, const error_category& ecat, const char* what_arg);
116    system_error(int ev, const error_category& ecat);
117
118    const error_code& code() const noexcept;
119    const char* what() const noexcept;
120};
121
122template <> struct is_error_condition_enum<errc>
123    : true_type { }
124
125error_code make_error_code(errc e) noexcept;
126error_condition make_error_condition(errc e) noexcept;
127
128// Comparison operators:
129bool operator==(const error_code& lhs, const error_code& rhs) noexcept;
130bool operator==(const error_code& lhs, const error_condition& rhs) noexcept;
131bool operator==(const error_condition& lhs, const error_code& rhs) noexcept;
132bool operator==(const error_condition& lhs, const error_condition& rhs) noexcept;
133bool operator!=(const error_code& lhs, const error_code& rhs) noexcept;
134bool operator!=(const error_code& lhs, const error_condition& rhs) noexcept;
135bool operator!=(const error_condition& lhs, const error_code& rhs) noexcept;
136bool operator!=(const error_condition& lhs, const error_condition& rhs) noexcept;
137
138template <> struct hash<std::error_code>;
139template <> struct hash<std::error_condition>;
140
141}  // std
142
143*/
144
145#include <__config>
146#include <__errc>
147#include <__functional/unary_function.h>
148#include <__functional_base>
149#include <compare>
150#include <stdexcept>
151#include <string>
152#include <type_traits>
153
154#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
155#pragma GCC system_header
156#endif
157
158_LIBCPP_BEGIN_NAMESPACE_STD
159
160// is_error_code_enum
161
162template <class _Tp>
163struct _LIBCPP_TEMPLATE_VIS is_error_code_enum
164    : public false_type {};
165
166#if _LIBCPP_STD_VER > 14
167template <class _Tp>
168inline constexpr bool is_error_code_enum_v = is_error_code_enum<_Tp>::value;
169#endif
170
171// is_error_condition_enum
172
173template <class _Tp>
174struct _LIBCPP_TEMPLATE_VIS is_error_condition_enum
175    : public false_type {};
176
177#if _LIBCPP_STD_VER > 14
178template <class _Tp>
179inline constexpr bool is_error_condition_enum_v = is_error_condition_enum<_Tp>::value;
180#endif
181
182template <>
183struct _LIBCPP_TEMPLATE_VIS is_error_condition_enum<errc>
184    : true_type { };
185
186#ifdef _LIBCPP_HAS_NO_STRONG_ENUMS
187template <>
188struct _LIBCPP_TEMPLATE_VIS is_error_condition_enum<errc::__lx>
189    : true_type { };
190#endif
191
192class _LIBCPP_TYPE_VIS error_condition;
193class _LIBCPP_TYPE_VIS error_code;
194
195// class error_category
196
197class _LIBCPP_HIDDEN __do_message;
198
199class _LIBCPP_TYPE_VIS error_category
200{
201public:
202    virtual ~error_category() _NOEXCEPT;
203
204#if defined(_LIBCPP_BUILDING_LIBRARY) && \
205    defined(_LIBCPP_DEPRECATED_ABI_LEGACY_LIBRARY_DEFINITIONS_FOR_INLINE_FUNCTIONS)
206    error_category() _NOEXCEPT;
207#else
208    _LIBCPP_INLINE_VISIBILITY
209    _LIBCPP_CONSTEXPR_AFTER_CXX11 error_category() _NOEXCEPT = default;
210#endif
211    error_category(const error_category&) = delete;
212    error_category& operator=(const error_category&) = delete;
213
214    virtual const char* name() const _NOEXCEPT = 0;
215    virtual error_condition default_error_condition(int __ev) const _NOEXCEPT;
216    virtual bool equivalent(int __code, const error_condition& __condition) const _NOEXCEPT;
217    virtual bool equivalent(const error_code& __code, int __condition) const _NOEXCEPT;
218    virtual string message(int __ev) const = 0;
219
220    _LIBCPP_INLINE_VISIBILITY
221    bool operator==(const error_category& __rhs) const _NOEXCEPT {return this == &__rhs;}
222
223    _LIBCPP_INLINE_VISIBILITY
224    bool operator!=(const error_category& __rhs) const _NOEXCEPT {return !(*this == __rhs);}
225
226    _LIBCPP_INLINE_VISIBILITY
227    bool operator< (const error_category& __rhs) const _NOEXCEPT {return this < &__rhs;}
228
229    friend class _LIBCPP_HIDDEN __do_message;
230};
231
232class _LIBCPP_HIDDEN __do_message
233    : public error_category
234{
235public:
236    virtual string message(int ev) const;
237};
238
239_LIBCPP_FUNC_VIS const error_category& generic_category() _NOEXCEPT;
240_LIBCPP_FUNC_VIS const error_category& system_category() _NOEXCEPT;
241
242class _LIBCPP_TYPE_VIS error_condition
243{
244    int __val_;
245    const error_category* __cat_;
246public:
247    _LIBCPP_INLINE_VISIBILITY
248    error_condition() _NOEXCEPT : __val_(0), __cat_(&generic_category()) {}
249
250    _LIBCPP_INLINE_VISIBILITY
251    error_condition(int __val, const error_category& __cat) _NOEXCEPT
252        : __val_(__val), __cat_(&__cat) {}
253
254    template <class _Ep>
255        _LIBCPP_INLINE_VISIBILITY
256        error_condition(_Ep __e,
257              typename enable_if<is_error_condition_enum<_Ep>::value>::type* = nullptr
258                                                                     ) _NOEXCEPT
259            {*this = make_error_condition(__e);}
260
261    _LIBCPP_INLINE_VISIBILITY
262    void assign(int __val, const error_category& __cat) _NOEXCEPT
263    {
264        __val_ = __val;
265        __cat_ = &__cat;
266    }
267
268    template <class _Ep>
269        _LIBCPP_INLINE_VISIBILITY
270        typename enable_if
271        <
272            is_error_condition_enum<_Ep>::value,
273            error_condition&
274        >::type
275        operator=(_Ep __e) _NOEXCEPT
276            {*this = make_error_condition(__e); return *this;}
277
278    _LIBCPP_INLINE_VISIBILITY
279    void clear() _NOEXCEPT
280    {
281        __val_ = 0;
282        __cat_ = &generic_category();
283    }
284
285    _LIBCPP_INLINE_VISIBILITY
286    int value() const _NOEXCEPT {return __val_;}
287
288    _LIBCPP_INLINE_VISIBILITY
289    const error_category& category() const _NOEXCEPT {return *__cat_;}
290    string message() const;
291
292    _LIBCPP_INLINE_VISIBILITY
293    explicit operator bool() const _NOEXCEPT {return __val_ != 0;}
294};
295
296inline _LIBCPP_INLINE_VISIBILITY
297error_condition
298make_error_condition(errc __e) _NOEXCEPT
299{
300    return error_condition(static_cast<int>(__e), generic_category());
301}
302
303inline _LIBCPP_INLINE_VISIBILITY
304bool
305operator<(const error_condition& __x, const error_condition& __y) _NOEXCEPT
306{
307    return __x.category() < __y.category()
308        || (__x.category() == __y.category() && __x.value() < __y.value());
309}
310
311// error_code
312
313class _LIBCPP_TYPE_VIS error_code
314{
315    int __val_;
316    const error_category* __cat_;
317public:
318    _LIBCPP_INLINE_VISIBILITY
319    error_code() _NOEXCEPT : __val_(0), __cat_(&system_category()) {}
320
321    _LIBCPP_INLINE_VISIBILITY
322    error_code(int __val, const error_category& __cat) _NOEXCEPT
323        : __val_(__val), __cat_(&__cat) {}
324
325    template <class _Ep>
326        _LIBCPP_INLINE_VISIBILITY
327        error_code(_Ep __e,
328                   typename enable_if<is_error_code_enum<_Ep>::value>::type* = nullptr
329                                                                     ) _NOEXCEPT
330            {*this = make_error_code(__e);}
331
332    _LIBCPP_INLINE_VISIBILITY
333    void assign(int __val, const error_category& __cat) _NOEXCEPT
334    {
335        __val_ = __val;
336        __cat_ = &__cat;
337    }
338
339    template <class _Ep>
340        _LIBCPP_INLINE_VISIBILITY
341        typename enable_if
342        <
343            is_error_code_enum<_Ep>::value,
344            error_code&
345        >::type
346        operator=(_Ep __e) _NOEXCEPT
347            {*this = make_error_code(__e); return *this;}
348
349    _LIBCPP_INLINE_VISIBILITY
350    void clear() _NOEXCEPT
351    {
352        __val_ = 0;
353        __cat_ = &system_category();
354    }
355
356    _LIBCPP_INLINE_VISIBILITY
357    int value() const _NOEXCEPT {return __val_;}
358
359    _LIBCPP_INLINE_VISIBILITY
360    const error_category& category() const _NOEXCEPT {return *__cat_;}
361
362    _LIBCPP_INLINE_VISIBILITY
363    error_condition default_error_condition() const _NOEXCEPT
364        {return __cat_->default_error_condition(__val_);}
365
366    string message() const;
367
368    _LIBCPP_INLINE_VISIBILITY
369    explicit operator bool() const _NOEXCEPT {return __val_ != 0;}
370};
371
372inline _LIBCPP_INLINE_VISIBILITY
373error_code
374make_error_code(errc __e) _NOEXCEPT
375{
376    return error_code(static_cast<int>(__e), generic_category());
377}
378
379inline _LIBCPP_INLINE_VISIBILITY
380bool
381operator<(const error_code& __x, const error_code& __y) _NOEXCEPT
382{
383    return __x.category() < __y.category()
384        || (__x.category() == __y.category() && __x.value() < __y.value());
385}
386
387inline _LIBCPP_INLINE_VISIBILITY
388bool
389operator==(const error_code& __x, const error_code& __y) _NOEXCEPT
390{
391    return __x.category() == __y.category() && __x.value() == __y.value();
392}
393
394inline _LIBCPP_INLINE_VISIBILITY
395bool
396operator==(const error_code& __x, const error_condition& __y) _NOEXCEPT
397{
398    return __x.category().equivalent(__x.value(), __y)
399        || __y.category().equivalent(__x, __y.value());
400}
401
402inline _LIBCPP_INLINE_VISIBILITY
403bool
404operator==(const error_condition& __x, const error_code& __y) _NOEXCEPT
405{
406    return __y == __x;
407}
408
409inline _LIBCPP_INLINE_VISIBILITY
410bool
411operator==(const error_condition& __x, const error_condition& __y) _NOEXCEPT
412{
413    return __x.category() == __y.category() && __x.value() == __y.value();
414}
415
416inline _LIBCPP_INLINE_VISIBILITY
417bool
418operator!=(const error_code& __x, const error_code& __y) _NOEXCEPT
419{return !(__x == __y);}
420
421inline _LIBCPP_INLINE_VISIBILITY
422bool
423operator!=(const error_code& __x, const error_condition& __y) _NOEXCEPT
424{return !(__x == __y);}
425
426inline _LIBCPP_INLINE_VISIBILITY
427bool
428operator!=(const error_condition& __x, const error_code& __y) _NOEXCEPT
429{return !(__x == __y);}
430
431inline _LIBCPP_INLINE_VISIBILITY
432bool
433operator!=(const error_condition& __x, const error_condition& __y) _NOEXCEPT
434{return !(__x == __y);}
435
436template <>
437struct _LIBCPP_TEMPLATE_VIS hash<error_code>
438    : public unary_function<error_code, size_t>
439{
440    _LIBCPP_INLINE_VISIBILITY
441    size_t operator()(const error_code& __ec) const _NOEXCEPT
442    {
443        return static_cast<size_t>(__ec.value());
444    }
445};
446
447template <>
448struct _LIBCPP_TEMPLATE_VIS hash<error_condition>
449    : public unary_function<error_condition, size_t>
450{
451    _LIBCPP_INLINE_VISIBILITY
452    size_t operator()(const error_condition& __ec) const _NOEXCEPT
453    {
454        return static_cast<size_t>(__ec.value());
455    }
456};
457
458// system_error
459
460class _LIBCPP_TYPE_VIS system_error
461    : public runtime_error
462{
463    error_code __ec_;
464public:
465    system_error(error_code __ec, const string& __what_arg);
466    system_error(error_code __ec, const char* __what_arg);
467    system_error(error_code __ec);
468    system_error(int __ev, const error_category& __ecat, const string& __what_arg);
469    system_error(int __ev, const error_category& __ecat, const char* __what_arg);
470    system_error(int __ev, const error_category& __ecat);
471    system_error(const system_error&) _NOEXCEPT = default;
472    ~system_error() _NOEXCEPT;
473
474    _LIBCPP_INLINE_VISIBILITY
475    const error_code& code() const _NOEXCEPT {return __ec_;}
476
477private:
478    static string __init(const error_code&, string);
479};
480
481_LIBCPP_NORETURN _LIBCPP_FUNC_VIS
482void __throw_system_error(int ev, const char* what_arg);
483
484_LIBCPP_END_NAMESPACE_STD
485
486#endif // _LIBCPP_SYSTEM_ERROR
487