libstdc++
chrono.h
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1 // chrono::duration and chrono::time_point -*- C++ -*-
2 
3 // Copyright (C) 2008-2022 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/bits/chrono.h
26  * This is an internal header file, included by other library headers.
27  * Do not attempt to use it directly. @headername{chrono}
28  */
29 
30 #ifndef _GLIBCXX_CHRONO_H
31 #define _GLIBCXX_CHRONO_H 1
32 
33 #pragma GCC system_header
34 
35 #if __cplusplus >= 201103L
36 
37 #include <ratio>
38 #include <type_traits>
39 #include <limits>
40 #include <ctime>
41 #include <bits/parse_numbers.h> // for literals support.
42 #if __cplusplus >= 202002L
43 # include <concepts>
44 # include <compare>
45 #endif
46 
47 namespace std _GLIBCXX_VISIBILITY(default)
48 {
49 _GLIBCXX_BEGIN_NAMESPACE_VERSION
50 
51 #if __cplusplus >= 201703L
52  namespace filesystem { struct __file_clock; };
53 #endif
54 
55  namespace chrono
56  {
57  /// @addtogroup chrono
58  /// @{
59 
60  /// `chrono::duration` represents a distance between two points in time
61  template<typename _Rep, typename _Period = ratio<1>>
62  class duration;
63 
64  /// `chrono::time_point` represents a point in time as measured by a clock
65  template<typename _Clock, typename _Dur = typename _Clock::duration>
66  class time_point;
67  /// @}
68  }
69 
70  /// @addtogroup chrono
71  /// @{
72 
73  // 20.11.4.3 specialization of common_type (for duration, sfinae-friendly)
74 
75  /// @cond undocumented
76 
77  template<typename _CT, typename _Period1, typename _Period2, typename = void>
78  struct __duration_common_type
79  { };
80 
81  template<typename _CT, typename _Period1, typename _Period2>
82  struct __duration_common_type<_CT, _Period1, _Period2,
83  __void_t<typename _CT::type>>
84  {
85  private:
86  using __gcd_num = __static_gcd<_Period1::num, _Period2::num>;
87  using __gcd_den = __static_gcd<_Period1::den, _Period2::den>;
88  using __cr = typename _CT::type;
89  using __r = ratio<__gcd_num::value,
90  (_Period1::den / __gcd_den::value) * _Period2::den>;
91 
92  public:
93  using type = chrono::duration<__cr, typename __r::type>;
94  };
95 
96  /// @endcond
97 
98  /// @{
99  /// @relates chrono::duration
100 
101  /// Specialization of common_type for chrono::duration types.
102  template<typename _Rep1, typename _Period1, typename _Rep2, typename _Period2>
103  struct common_type<chrono::duration<_Rep1, _Period1>,
104  chrono::duration<_Rep2, _Period2>>
105  : __duration_common_type<common_type<_Rep1, _Rep2>,
106  typename _Period1::type,
107  typename _Period2::type>
108  { };
109 
110  /// Specialization of common_type for two identical chrono::duration types.
111  template<typename _Rep, typename _Period>
112  struct common_type<chrono::duration<_Rep, _Period>,
113  chrono::duration<_Rep, _Period>>
114  {
116  typename _Period::type>;
117  };
118 
119  /// Specialization of common_type for one chrono::duration type.
120  template<typename _Rep, typename _Period>
121  struct common_type<chrono::duration<_Rep, _Period>>
122  {
124  typename _Period::type>;
125  };
126  /// @}
127 
128  // 20.11.4.3 specialization of common_type (for time_point, sfinae-friendly)
129 
130  /// @cond undocumented
131 
132  template<typename _CT, typename _Clock, typename = void>
133  struct __timepoint_common_type
134  { };
135 
136  template<typename _CT, typename _Clock>
137  struct __timepoint_common_type<_CT, _Clock, __void_t<typename _CT::type>>
138  {
139  using type = chrono::time_point<_Clock, typename _CT::type>;
140  };
141 
142  /// @endcond
143 
144  /// @{
145  /// @relates chrono::time_point
146 
147  /// Specialization of common_type for chrono::time_point types.
148  template<typename _Clock, typename _Duration1, typename _Duration2>
149  struct common_type<chrono::time_point<_Clock, _Duration1>,
150  chrono::time_point<_Clock, _Duration2>>
151  : __timepoint_common_type<common_type<_Duration1, _Duration2>, _Clock>
152  { };
153 
154  /// Specialization of common_type for two identical chrono::time_point types.
155  template<typename _Clock, typename _Duration>
156  struct common_type<chrono::time_point<_Clock, _Duration>,
157  chrono::time_point<_Clock, _Duration>>
159 
160  /// Specialization of common_type for one chrono::time_point type.
161  template<typename _Clock, typename _Duration>
162  struct common_type<chrono::time_point<_Clock, _Duration>>
164  /// @}
165 
166  /// @} group chrono
167 
168  namespace chrono
169  {
170  /// @addtogroup chrono
171  /// @{
172 
173  /// @cond undocumented
174 
175  // Primary template for duration_cast impl.
176  template<typename _ToDur, typename _CF, typename _CR,
177  bool _NumIsOne = false, bool _DenIsOne = false>
178  struct __duration_cast_impl
179  {
180  template<typename _Rep, typename _Period>
181  static constexpr _ToDur
182  __cast(const duration<_Rep, _Period>& __d)
183  {
184  typedef typename _ToDur::rep __to_rep;
185  return _ToDur(static_cast<__to_rep>(static_cast<_CR>(__d.count())
186  * static_cast<_CR>(_CF::num)
187  / static_cast<_CR>(_CF::den)));
188  }
189  };
190 
191  template<typename _ToDur, typename _CF, typename _CR>
192  struct __duration_cast_impl<_ToDur, _CF, _CR, true, true>
193  {
194  template<typename _Rep, typename _Period>
195  static constexpr _ToDur
196  __cast(const duration<_Rep, _Period>& __d)
197  {
198  typedef typename _ToDur::rep __to_rep;
199  return _ToDur(static_cast<__to_rep>(__d.count()));
200  }
201  };
202 
203  template<typename _ToDur, typename _CF, typename _CR>
204  struct __duration_cast_impl<_ToDur, _CF, _CR, true, false>
205  {
206  template<typename _Rep, typename _Period>
207  static constexpr _ToDur
208  __cast(const duration<_Rep, _Period>& __d)
209  {
210  typedef typename _ToDur::rep __to_rep;
211  return _ToDur(static_cast<__to_rep>(
212  static_cast<_CR>(__d.count()) / static_cast<_CR>(_CF::den)));
213  }
214  };
215 
216  template<typename _ToDur, typename _CF, typename _CR>
217  struct __duration_cast_impl<_ToDur, _CF, _CR, false, true>
218  {
219  template<typename _Rep, typename _Period>
220  static constexpr _ToDur
221  __cast(const duration<_Rep, _Period>& __d)
222  {
223  typedef typename _ToDur::rep __to_rep;
224  return _ToDur(static_cast<__to_rep>(
225  static_cast<_CR>(__d.count()) * static_cast<_CR>(_CF::num)));
226  }
227  };
228 
229  template<typename _Tp>
230  struct __is_duration
232  { };
233 
234  template<typename _Rep, typename _Period>
235  struct __is_duration<duration<_Rep, _Period>>
237  { };
238 
239  template<typename _Tp>
240  using __enable_if_is_duration
241  = typename enable_if<__is_duration<_Tp>::value, _Tp>::type;
242 
243  template<typename _Tp>
244  using __disable_if_is_duration
245  = typename enable_if<!__is_duration<_Tp>::value, _Tp>::type;
246 
247  /// @endcond
248 
249  /** Convert a `duration` to type `ToDur`.
250  *
251  * If the duration cannot be represented accurately in the result type,
252  * returns the result of integer truncation (i.e., rounded towards zero).
253  *
254  * @tparam _ToDur The result type must be a `duration`.
255  * @param __d A duration.
256  * @return The value of `__d` converted to type `_ToDur`.
257  * @since C++11
258  */
259  template<typename _ToDur, typename _Rep, typename _Period>
260  _GLIBCXX_NODISCARD
261  constexpr __enable_if_is_duration<_ToDur>
263  {
264  typedef typename _ToDur::period __to_period;
265  typedef typename _ToDur::rep __to_rep;
267  typedef typename common_type<__to_rep, _Rep, intmax_t>::type __cr;
268  typedef __duration_cast_impl<_ToDur, __cf, __cr,
269  __cf::num == 1, __cf::den == 1> __dc;
270  return __dc::__cast(__d);
271  }
272 
273  /** Trait indicating whether to treat a type as a floating-point type.
274  *
275  * The chrono library uses this trait to tell whether a `duration` can
276  * represent fractional values of the given precision, or only integral
277  * values.
278  *
279  * You should specialize this trait for your own numeric types that are
280  * used with `duration` and can represent non-integral values.
281  *
282  * @since C++11
283  */
284  template<typename _Rep>
286  : is_floating_point<_Rep>
287  { };
288 
289 #if __cplusplus > 201402L
290  template <typename _Rep>
291  inline constexpr bool treat_as_floating_point_v =
293 #endif // C++17
294 
295 #if __cplusplus > 201703L
296  template<typename _Tp>
297  struct is_clock;
298 
299  template<typename _Tp>
300  inline constexpr bool is_clock_v = is_clock<_Tp>::value;
301 
302 #if __cpp_lib_concepts
303  template<typename _Tp>
304  struct is_clock : false_type
305  { };
306 
307  template<typename _Tp>
308  requires requires {
309  typename _Tp::rep;
310  typename _Tp::period;
311  typename _Tp::duration;
312  typename _Tp::time_point::clock;
313  typename _Tp::time_point::duration;
314  { &_Tp::is_steady } -> same_as<const bool*>;
315  { _Tp::now() } -> same_as<typename _Tp::time_point>;
316  requires same_as<typename _Tp::duration,
317  duration<typename _Tp::rep, typename _Tp::period>>;
318  requires same_as<typename _Tp::time_point::duration,
319  typename _Tp::duration>;
320  }
321  struct is_clock<_Tp> : true_type
322  { };
323 #else
324  template<typename _Tp, typename = void>
325  struct __is_clock_impl : false_type
326  { };
327 
328  template<typename _Tp>
329  struct __is_clock_impl<_Tp,
330  void_t<typename _Tp::rep, typename _Tp::period,
331  typename _Tp::duration,
332  typename _Tp::time_point::duration,
333  decltype(_Tp::is_steady),
334  decltype(_Tp::now())>>
335  : __and_<is_same<typename _Tp::duration,
336  duration<typename _Tp::rep, typename _Tp::period>>,
337  is_same<typename _Tp::time_point::duration,
338  typename _Tp::duration>,
339  is_same<decltype(&_Tp::is_steady), const bool*>,
340  is_same<decltype(_Tp::now()), typename _Tp::time_point>>::type
341  { };
342 
343  template<typename _Tp>
344  struct is_clock : __is_clock_impl<_Tp>::type
345  { };
346 #endif
347 #endif // C++20
348 
349 #if __cplusplus >= 201703L
350 # define __cpp_lib_chrono 201611L
351 
352  /** Convert a `duration` to type `ToDur` and round down.
353  *
354  * If the duration cannot be represented exactly in the result type,
355  * returns the closest value that is less than the argument.
356  *
357  * @tparam _ToDur The result type must be a `duration`.
358  * @param __d A duration.
359  * @return The value of `__d` converted to type `_ToDur`.
360  * @since C++17
361  */
362  template<typename _ToDur, typename _Rep, typename _Period>
363  [[nodiscard]] constexpr __enable_if_is_duration<_ToDur>
365  {
366  auto __to = chrono::duration_cast<_ToDur>(__d);
367  if (__to > __d)
368  return __to - _ToDur{1};
369  return __to;
370  }
371 
372  /** Convert a `duration` to type `ToDur` and round up.
373  *
374  * If the duration cannot be represented exactly in the result type,
375  * returns the closest value that is greater than the argument.
376  *
377  * @tparam _ToDur The result type must be a `duration`.
378  * @param __d A duration.
379  * @return The value of `__d` converted to type `_ToDur`.
380  * @since C++17
381  */
382  template<typename _ToDur, typename _Rep, typename _Period>
383  [[nodiscard]] constexpr __enable_if_is_duration<_ToDur>
385  {
386  auto __to = chrono::duration_cast<_ToDur>(__d);
387  if (__to < __d)
388  return __to + _ToDur{1};
389  return __to;
390  }
391 
392  /** Convert a `duration` to type `ToDur` and round to the closest value.
393  *
394  * If the duration cannot be represented exactly in the result type,
395  * returns the closest value, rounding ties to even.
396  *
397  * @tparam _ToDur The result type must be a `duration` with a
398  * non-floating-point `rep` type.
399  * @param __d A duration.
400  * @return The value of `__d` converted to type `_ToDur`.
401  * @since C++17
402  */
403  template <typename _ToDur, typename _Rep, typename _Period>
404  [[nodiscard]] constexpr
405  enable_if_t<
406  __and_<__is_duration<_ToDur>,
407  __not_<treat_as_floating_point<typename _ToDur::rep>>>::value,
408  _ToDur>
410  {
411  _ToDur __t0 = chrono::floor<_ToDur>(__d);
412  _ToDur __t1 = __t0 + _ToDur{1};
413  auto __diff0 = __d - __t0;
414  auto __diff1 = __t1 - __d;
415  if (__diff0 == __diff1)
416  {
417  if (__t0.count() & 1)
418  return __t1;
419  return __t0;
420  }
421  else if (__diff0 < __diff1)
422  return __t0;
423  return __t1;
424  }
425 
426  /** The absolute (non-negative) value of a duration.
427  *
428  * @param __d A duration with a signed `rep` type.
429  * @return A duration of the same type as the argument, with value |d|.
430  * @since C++17
431  */
432  template<typename _Rep, typename _Period>
433  [[nodiscard]] constexpr
434  enable_if_t<numeric_limits<_Rep>::is_signed, duration<_Rep, _Period>>
436  {
437  if (__d >= __d.zero())
438  return __d;
439  return -__d;
440  }
441 
442  // Make chrono::ceil<D> also usable as chrono::__detail::ceil<D>.
443  namespace __detail { using chrono::ceil; }
444 
445 #else // ! C++17
446 
447  // We want to use ceil even when compiling for earlier standards versions.
448  // C++11 only allows a single statement in a constexpr function, so we
449  // need to move the comparison into a separate function, __ceil_impl.
450  namespace __detail
451  {
452  template<typename _Tp, typename _Up>
453  constexpr _Tp
454  __ceil_impl(const _Tp& __t, const _Up& __u)
455  {
456  return (__t < __u) ? (__t + _Tp{1}) : __t;
457  }
458 
459  // C++11-friendly version of std::chrono::ceil<D> for internal use.
460  template<typename _ToDur, typename _Rep, typename _Period>
461  constexpr _ToDur
462  ceil(const duration<_Rep, _Period>& __d)
463  {
464  return __detail::__ceil_impl(chrono::duration_cast<_ToDur>(__d), __d);
465  }
466  }
467 #endif // C++17
468 
469  /// duration_values
470  template<typename _Rep>
472  {
473  static constexpr _Rep
474  zero() noexcept
475  { return _Rep(0); }
476 
477  static constexpr _Rep
478  max() noexcept
479  { return numeric_limits<_Rep>::max(); }
480 
481  static constexpr _Rep
482  min() noexcept
483  { return numeric_limits<_Rep>::lowest(); }
484  };
485 
486  /// @cond undocumented
487 
488  template<typename _Tp>
489  struct __is_ratio
491  { };
492 
493  template<intmax_t _Num, intmax_t _Den>
494  struct __is_ratio<ratio<_Num, _Den>>
496  { };
497 
498  /// @endcond
499 
500  template<typename _Rep, typename _Period>
501  class duration
502  {
503  static_assert(!__is_duration<_Rep>::value, "rep cannot be a duration");
504  static_assert(__is_ratio<_Period>::value,
505  "period must be a specialization of ratio");
506  static_assert(_Period::num > 0, "period must be positive");
507 
508  template<typename _Rep2>
510 
511  static constexpr intmax_t
512  _S_gcd(intmax_t __m, intmax_t __n) noexcept
513  {
514  // Duration only allows positive periods so we don't need to
515  // handle negative values here (unlike __static_gcd and std::gcd).
516 #if __cplusplus >= 201402L
517  do
518  {
519  intmax_t __rem = __m % __n;
520  __m = __n;
521  __n = __rem;
522  }
523  while (__n != 0);
524  return __m;
525 #else
526  // C++11 doesn't allow loops in constexpr functions, but this
527  // recursive version can be more expensive to evaluate.
528  return (__n == 0) ? __m : _S_gcd(__n, __m % __n);
529 #endif
530  }
531 
532  // _GLIBCXX_RESOLVE_LIB_DEFECTS
533  // 2094. overflow shouldn't participate in overload resolution
534  // 3090. What is [2094] intended to mean?
535  // This only produces a valid type if no overflow occurs.
536  template<typename _R1, typename _R2,
537  intmax_t __gcd1 = _S_gcd(_R1::num, _R2::num),
538  intmax_t __gcd2 = _S_gcd(_R1::den, _R2::den)>
539  using __divide = ratio<(_R1::num / __gcd1) * (_R2::den / __gcd2),
540  (_R1::den / __gcd2) * (_R2::num / __gcd1)>;
541 
542  // _Period2 is an exact multiple of _Period
543  template<typename _Period2>
544  using __is_harmonic
545  = __bool_constant<__divide<_Period2, _Period>::den == 1>;
546 
547  public:
548 
549  using rep = _Rep;
550  using period = typename _Period::type;
551 
552  // 20.11.5.1 construction / copy / destroy
553  constexpr duration() = default;
554 
555  duration(const duration&) = default;
556 
557  // _GLIBCXX_RESOLVE_LIB_DEFECTS
558  // 3050. Conversion specification problem in chrono::duration
559  template<typename _Rep2, typename = _Require<
561  __or_<__is_float<rep>, __not_<__is_float<_Rep2>>>>>
562  constexpr explicit duration(const _Rep2& __rep)
563  : __r(static_cast<rep>(__rep)) { }
564 
565  template<typename _Rep2, typename _Period2, typename = _Require<
567  __or_<__is_float<rep>,
568  __and_<__is_harmonic<_Period2>,
569  __not_<__is_float<_Rep2>>>>>>
570  constexpr duration(const duration<_Rep2, _Period2>& __d)
571  : __r(duration_cast<duration>(__d).count()) { }
572 
573  ~duration() = default;
574  duration& operator=(const duration&) = default;
575 
576  // 20.11.5.2 observer
577  constexpr rep
578  count() const
579  { return __r; }
580 
581  // 20.11.5.3 arithmetic
582 
584  operator+() const
585  { return duration<typename common_type<rep>::type, period>(__r); }
586 
588  operator-() const
589  { return duration<typename common_type<rep>::type, period>(-__r); }
590 
591  _GLIBCXX17_CONSTEXPR duration&
592  operator++()
593  {
594  ++__r;
595  return *this;
596  }
597 
598  _GLIBCXX17_CONSTEXPR duration
599  operator++(int)
600  { return duration(__r++); }
601 
602  _GLIBCXX17_CONSTEXPR duration&
603  operator--()
604  {
605  --__r;
606  return *this;
607  }
608 
609  _GLIBCXX17_CONSTEXPR duration
610  operator--(int)
611  { return duration(__r--); }
612 
613  _GLIBCXX17_CONSTEXPR duration&
614  operator+=(const duration& __d)
615  {
616  __r += __d.count();
617  return *this;
618  }
619 
620  _GLIBCXX17_CONSTEXPR duration&
621  operator-=(const duration& __d)
622  {
623  __r -= __d.count();
624  return *this;
625  }
626 
627  _GLIBCXX17_CONSTEXPR duration&
628  operator*=(const rep& __rhs)
629  {
630  __r *= __rhs;
631  return *this;
632  }
633 
634  _GLIBCXX17_CONSTEXPR duration&
635  operator/=(const rep& __rhs)
636  {
637  __r /= __rhs;
638  return *this;
639  }
640 
641  // DR 934.
642  template<typename _Rep2 = rep>
643  _GLIBCXX17_CONSTEXPR
645  duration&>::type
646  operator%=(const rep& __rhs)
647  {
648  __r %= __rhs;
649  return *this;
650  }
651 
652  template<typename _Rep2 = rep>
653  _GLIBCXX17_CONSTEXPR
655  duration&>::type
656  operator%=(const duration& __d)
657  {
658  __r %= __d.count();
659  return *this;
660  }
661 
662  // 20.11.5.4 special values
663  static constexpr duration
664  zero() noexcept
665  { return duration(duration_values<rep>::zero()); }
666 
667  static constexpr duration
668  min() noexcept
669  { return duration(duration_values<rep>::min()); }
670 
671  static constexpr duration
672  max() noexcept
673  { return duration(duration_values<rep>::max()); }
674 
675  private:
676  rep __r;
677  };
678 
679  /// @{
680  /// @relates std::chrono::duration
681 
682  /// The sum of two durations.
683  template<typename _Rep1, typename _Period1,
684  typename _Rep2, typename _Period2>
685  constexpr typename common_type<duration<_Rep1, _Period1>,
688  const duration<_Rep2, _Period2>& __rhs)
689  {
690  typedef duration<_Rep1, _Period1> __dur1;
691  typedef duration<_Rep2, _Period2> __dur2;
692  typedef typename common_type<__dur1,__dur2>::type __cd;
693  return __cd(__cd(__lhs).count() + __cd(__rhs).count());
694  }
695 
696  /// The difference between two durations.
697  template<typename _Rep1, typename _Period1,
698  typename _Rep2, typename _Period2>
699  constexpr typename common_type<duration<_Rep1, _Period1>,
702  const duration<_Rep2, _Period2>& __rhs)
703  {
704  typedef duration<_Rep1, _Period1> __dur1;
705  typedef duration<_Rep2, _Period2> __dur2;
706  typedef typename common_type<__dur1,__dur2>::type __cd;
707  return __cd(__cd(__lhs).count() - __cd(__rhs).count());
708  }
709 
710  /// @}
711 
712  /// @cond undocumented
713 
714  // SFINAE helper to obtain common_type<_Rep1, _Rep2> only if _Rep2
715  // is implicitly convertible to it.
716  // _GLIBCXX_RESOLVE_LIB_DEFECTS
717  // 3050. Conversion specification problem in chrono::duration constructor
718  template<typename _Rep1, typename _Rep2,
719  typename _CRep = typename common_type<_Rep1, _Rep2>::type>
720  using __common_rep_t = typename
722 
723  /// @endcond
724 
725  /** @{
726  * Arithmetic operators for chrono::duration
727  * @relates std::chrono::duration
728  */
729 
730  template<typename _Rep1, typename _Period, typename _Rep2>
731  constexpr duration<__common_rep_t<_Rep1, _Rep2>, _Period>
732  operator*(const duration<_Rep1, _Period>& __d, const _Rep2& __s)
733  {
735  __cd;
736  return __cd(__cd(__d).count() * __s);
737  }
738 
739  template<typename _Rep1, typename _Rep2, typename _Period>
740  constexpr duration<__common_rep_t<_Rep2, _Rep1>, _Period>
741  operator*(const _Rep1& __s, const duration<_Rep2, _Period>& __d)
742  { return __d * __s; }
743 
744  template<typename _Rep1, typename _Period, typename _Rep2>
745  constexpr
746  duration<__common_rep_t<_Rep1, __disable_if_is_duration<_Rep2>>, _Period>
747  operator/(const duration<_Rep1, _Period>& __d, const _Rep2& __s)
748  {
750  __cd;
751  return __cd(__cd(__d).count() / __s);
752  }
753 
754  template<typename _Rep1, typename _Period1,
755  typename _Rep2, typename _Period2>
756  constexpr typename common_type<_Rep1, _Rep2>::type
758  const duration<_Rep2, _Period2>& __rhs)
759  {
760  typedef duration<_Rep1, _Period1> __dur1;
761  typedef duration<_Rep2, _Period2> __dur2;
762  typedef typename common_type<__dur1,__dur2>::type __cd;
763  return __cd(__lhs).count() / __cd(__rhs).count();
764  }
765 
766  // DR 934.
767  template<typename _Rep1, typename _Period, typename _Rep2>
768  constexpr
769  duration<__common_rep_t<_Rep1, __disable_if_is_duration<_Rep2>>, _Period>
770  operator%(const duration<_Rep1, _Period>& __d, const _Rep2& __s)
771  {
773  __cd;
774  return __cd(__cd(__d).count() % __s);
775  }
776 
777  template<typename _Rep1, typename _Period1,
778  typename _Rep2, typename _Period2>
779  constexpr typename common_type<duration<_Rep1, _Period1>,
780  duration<_Rep2, _Period2>>::type
782  const duration<_Rep2, _Period2>& __rhs)
783  {
784  typedef duration<_Rep1, _Period1> __dur1;
785  typedef duration<_Rep2, _Period2> __dur2;
786  typedef typename common_type<__dur1,__dur2>::type __cd;
787  return __cd(__cd(__lhs).count() % __cd(__rhs).count());
788  }
789  /// @}
790 
791  // comparisons
792 
793  /** @{
794  * Comparisons for chrono::duration
795  * @relates std::chrono::duration
796  */
797 
798  template<typename _Rep1, typename _Period1,
799  typename _Rep2, typename _Period2>
800  constexpr bool
802  const duration<_Rep2, _Period2>& __rhs)
803  {
804  typedef duration<_Rep1, _Period1> __dur1;
805  typedef duration<_Rep2, _Period2> __dur2;
806  typedef typename common_type<__dur1,__dur2>::type __ct;
807  return __ct(__lhs).count() == __ct(__rhs).count();
808  }
809 
810  template<typename _Rep1, typename _Period1,
811  typename _Rep2, typename _Period2>
812  constexpr bool
814  const duration<_Rep2, _Period2>& __rhs)
815  {
816  typedef duration<_Rep1, _Period1> __dur1;
817  typedef duration<_Rep2, _Period2> __dur2;
818  typedef typename common_type<__dur1,__dur2>::type __ct;
819  return __ct(__lhs).count() < __ct(__rhs).count();
820  }
821 
822 #if __cpp_lib_three_way_comparison
823  template<typename _Rep1, typename _Period1,
824  typename _Rep2, typename _Period2>
825  requires three_way_comparable<common_type_t<_Rep1, _Rep2>>
826  constexpr auto
827  operator<=>(const duration<_Rep1, _Period1>& __lhs,
828  const duration<_Rep2, _Period2>& __rhs)
829  {
831  duration<_Rep2, _Period2>>;
832  return __ct(__lhs).count() <=> __ct(__rhs).count();
833  }
834 #else
835  template<typename _Rep1, typename _Period1,
836  typename _Rep2, typename _Period2>
837  constexpr bool
839  const duration<_Rep2, _Period2>& __rhs)
840  { return !(__lhs == __rhs); }
841 #endif
842 
843  template<typename _Rep1, typename _Period1,
844  typename _Rep2, typename _Period2>
845  constexpr bool
847  const duration<_Rep2, _Period2>& __rhs)
848  { return !(__rhs < __lhs); }
849 
850  template<typename _Rep1, typename _Period1,
851  typename _Rep2, typename _Period2>
852  constexpr bool
854  const duration<_Rep2, _Period2>& __rhs)
855  { return __rhs < __lhs; }
856 
857  template<typename _Rep1, typename _Period1,
858  typename _Rep2, typename _Period2>
859  constexpr bool
861  const duration<_Rep2, _Period2>& __rhs)
862  { return !(__lhs < __rhs); }
863 
864  /// @}
865 
866  /// @cond undocumented
867 #ifdef _GLIBCXX_USE_C99_STDINT_TR1
868 # define _GLIBCXX_CHRONO_INT64_T int64_t
869 #elif defined __INT64_TYPE__
870 # define _GLIBCXX_CHRONO_INT64_T __INT64_TYPE__
871 #else
873  "Representation type for nanoseconds must have at least 64 bits");
874 # define _GLIBCXX_CHRONO_INT64_T long long
875 #endif
876  /// @endcond
877 
878  /// nanoseconds
880 
881  /// microseconds
883 
884  /// milliseconds
886 
887  /// seconds
889 
890  /// minutes
892 
893  /// hours
895 
896 #if __cplusplus > 201703L
897  /// days
899 
900  /// weeks
902 
903  /// years
905 
906  /// months
908 #endif // C++20
909 
910 #undef _GLIBCXX_CHRONO_INT64_T
911 
912  template<typename _Clock, typename _Dur>
914  {
915  static_assert(__is_duration<_Dur>::value,
916  "duration must be a specialization of std::chrono::duration");
917 
918  public:
919  typedef _Clock clock;
920  typedef _Dur duration;
921  typedef typename duration::rep rep;
922  typedef typename duration::period period;
923 
924  constexpr time_point() : __d(duration::zero())
925  { }
926 
927  constexpr explicit time_point(const duration& __dur)
928  : __d(__dur)
929  { }
930 
931  // conversions
932  template<typename _Dur2,
933  typename = _Require<is_convertible<_Dur2, _Dur>>>
934  constexpr time_point(const time_point<clock, _Dur2>& __t)
935  : __d(__t.time_since_epoch())
936  { }
937 
938  // observer
939  constexpr duration
940  time_since_epoch() const
941  { return __d; }
942 
943 #if __cplusplus > 201703L
944  constexpr time_point&
945  operator++()
946  {
947  ++__d;
948  return *this;
949  }
950 
951  constexpr time_point
952  operator++(int)
953  { return time_point{__d++}; }
954 
955  constexpr time_point&
956  operator--()
957  {
958  --__d;
959  return *this;
960  }
961 
962  constexpr time_point
963  operator--(int)
964  { return time_point{__d--}; }
965 #endif
966 
967  // arithmetic
968  _GLIBCXX17_CONSTEXPR time_point&
969  operator+=(const duration& __dur)
970  {
971  __d += __dur;
972  return *this;
973  }
974 
975  _GLIBCXX17_CONSTEXPR time_point&
976  operator-=(const duration& __dur)
977  {
978  __d -= __dur;
979  return *this;
980  }
981 
982  // special values
983  static constexpr time_point
984  min() noexcept
985  { return time_point(duration::min()); }
986 
987  static constexpr time_point
988  max() noexcept
989  { return time_point(duration::max()); }
990 
991  private:
992  duration __d;
993  };
994 
995  /** Convert a `time_point` to use `duration` type `ToDur`.
996  *
997  * The result is the same time point as measured by the same clock, but
998  * using the specified `duration` to represent the time.
999  * If the time point cannot be represented accurately in the result type,
1000  * returns the result of integer truncation (i.e., rounded towards zero).
1001  *
1002  * @tparam _ToDur The `duration` type to use for the result.
1003  * @param __t A time point.
1004  * @return The value of `__t` converted to use type `_ToDur`.
1005  * @since C++11
1006  */
1007  template<typename _ToDur, typename _Clock, typename _Dur>
1008  _GLIBCXX_NODISCARD constexpr
1009  __enable_if_t<__is_duration<_ToDur>::value, time_point<_Clock, _ToDur>>
1011  {
1012  typedef time_point<_Clock, _ToDur> __time_point;
1013  return __time_point(duration_cast<_ToDur>(__t.time_since_epoch()));
1014  }
1015 
1016 #if __cplusplus > 201402L
1017  /** Convert a `time_point` to type `ToDur` and round down.
1018  *
1019  * The result is the same time point as measured by the same clock, but
1020  * using the specified `duration` to represent the time.
1021  * If the time point cannot be represented exactly in the result type,
1022  * returns the closest value that is less than the argument.
1023  *
1024  * @tparam _ToDur The `duration` type to use for the result.
1025  * @param __t A time point.
1026  * @return The value of `__d` converted to type `_ToDur`.
1027  * @since C++17
1028  */
1029  template<typename _ToDur, typename _Clock, typename _Dur>
1030  [[nodiscard]] constexpr
1031  enable_if_t<__is_duration<_ToDur>::value, time_point<_Clock, _ToDur>>
1033  {
1035  chrono::floor<_ToDur>(__tp.time_since_epoch())};
1036  }
1037 
1038  /** Convert a `time_point` to type `ToDur` and round up.
1039  *
1040  * The result is the same time point as measured by the same clock, but
1041  * using the specified `duration` to represent the time.
1042  * If the time point cannot be represented exactly in the result type,
1043  * returns the closest value that is greater than the argument.
1044  *
1045  * @tparam _ToDur The `duration` type to use for the result.
1046  * @param __t A time point.
1047  * @return The value of `__d` converted to type `_ToDur`.
1048  * @since C++17
1049  */
1050  template<typename _ToDur, typename _Clock, typename _Dur>
1051  [[nodiscard]] constexpr
1052  enable_if_t<__is_duration<_ToDur>::value, time_point<_Clock, _ToDur>>
1054  {
1056  chrono::ceil<_ToDur>(__tp.time_since_epoch())};
1057  }
1058 
1059  /** Convert a `time_point` to type `ToDur` and round to the closest value.
1060  *
1061  * The result is the same time point as measured by the same clock, but
1062  * using the specified `duration` to represent the time.
1063  * If the time point cannot be represented exactly in the result type,
1064  * returns the closest value, rounding ties to even.
1065  *
1066  * @tparam _ToDur The `duration` type to use for the result,
1067  * which must have a non-floating-point `rep` type.
1068  * @param __t A time point.
1069  * @return The value of `__d` converted to type `_ToDur`.
1070  * @since C++17
1071  */
1072  template<typename _ToDur, typename _Clock, typename _Dur>
1073  [[nodiscard]] constexpr
1074  enable_if_t<
1075  __and_<__is_duration<_ToDur>,
1076  __not_<treat_as_floating_point<typename _ToDur::rep>>>::value,
1077  time_point<_Clock, _ToDur>>
1079  {
1081  chrono::round<_ToDur>(__tp.time_since_epoch())};
1082  }
1083 #endif // C++17
1084 
1085  /// @{
1086  /// @relates time_point
1087 
1088  /// Adjust a time point forwards by the given duration.
1089  template<typename _Clock, typename _Dur1,
1090  typename _Rep2, typename _Period2>
1091  constexpr time_point<_Clock,
1094  const duration<_Rep2, _Period2>& __rhs)
1095  {
1096  typedef duration<_Rep2, _Period2> __dur2;
1097  typedef typename common_type<_Dur1,__dur2>::type __ct;
1098  typedef time_point<_Clock, __ct> __time_point;
1099  return __time_point(__lhs.time_since_epoch() + __rhs);
1100  }
1101 
1102  /// Adjust a time point forwards by the given duration.
1103  template<typename _Rep1, typename _Period1,
1104  typename _Clock, typename _Dur2>
1105  constexpr time_point<_Clock,
1106  typename common_type<duration<_Rep1, _Period1>, _Dur2>::type>
1108  const time_point<_Clock, _Dur2>& __rhs)
1109  {
1110  typedef duration<_Rep1, _Period1> __dur1;
1111  typedef typename common_type<__dur1,_Dur2>::type __ct;
1112  typedef time_point<_Clock, __ct> __time_point;
1113  return __time_point(__rhs.time_since_epoch() + __lhs);
1114  }
1115 
1116  /// Adjust a time point backwards by the given duration.
1117  template<typename _Clock, typename _Dur1,
1118  typename _Rep2, typename _Period2>
1119  constexpr time_point<_Clock,
1122  const duration<_Rep2, _Period2>& __rhs)
1123  {
1124  typedef duration<_Rep2, _Period2> __dur2;
1125  typedef typename common_type<_Dur1,__dur2>::type __ct;
1126  typedef time_point<_Clock, __ct> __time_point;
1127  return __time_point(__lhs.time_since_epoch() -__rhs);
1128  }
1129 
1130  /// The difference between two time points (as a duration)
1131  template<typename _Clock, typename _Dur1, typename _Dur2>
1132  constexpr typename common_type<_Dur1, _Dur2>::type
1134  const time_point<_Clock, _Dur2>& __rhs)
1135  { return __lhs.time_since_epoch() - __rhs.time_since_epoch(); }
1136  /// @}
1137 
1138  /** @{
1139  * Comparisons for time_point
1140  * @relates chrono::time_point
1141  */
1142 
1143  template<typename _Clock, typename _Dur1, typename _Dur2>
1144  constexpr bool
1145  operator==(const time_point<_Clock, _Dur1>& __lhs,
1146  const time_point<_Clock, _Dur2>& __rhs)
1147  { return __lhs.time_since_epoch() == __rhs.time_since_epoch(); }
1148 
1149 #if __cpp_lib_three_way_comparison
1150  template<typename _Clock, typename _Dur1,
1151  three_way_comparable_with<_Dur1> _Dur2>
1152  constexpr auto
1153  operator<=>(const time_point<_Clock, _Dur1>& __lhs,
1154  const time_point<_Clock, _Dur2>& __rhs)
1155  { return __lhs.time_since_epoch() <=> __rhs.time_since_epoch(); }
1156 #else
1157  template<typename _Clock, typename _Dur1, typename _Dur2>
1158  constexpr bool
1159  operator!=(const time_point<_Clock, _Dur1>& __lhs,
1160  const time_point<_Clock, _Dur2>& __rhs)
1161  { return !(__lhs == __rhs); }
1162 #endif
1163 
1164  template<typename _Clock, typename _Dur1, typename _Dur2>
1165  constexpr bool
1166  operator<(const time_point<_Clock, _Dur1>& __lhs,
1167  const time_point<_Clock, _Dur2>& __rhs)
1168  { return __lhs.time_since_epoch() < __rhs.time_since_epoch(); }
1169 
1170  template<typename _Clock, typename _Dur1, typename _Dur2>
1171  constexpr bool
1172  operator<=(const time_point<_Clock, _Dur1>& __lhs,
1173  const time_point<_Clock, _Dur2>& __rhs)
1174  { return !(__rhs < __lhs); }
1175 
1176  template<typename _Clock, typename _Dur1, typename _Dur2>
1177  constexpr bool
1178  operator>(const time_point<_Clock, _Dur1>& __lhs,
1179  const time_point<_Clock, _Dur2>& __rhs)
1180  { return __rhs < __lhs; }
1181 
1182  template<typename _Clock, typename _Dur1, typename _Dur2>
1183  constexpr bool
1184  operator>=(const time_point<_Clock, _Dur1>& __lhs,
1185  const time_point<_Clock, _Dur2>& __rhs)
1186  { return !(__lhs < __rhs); }
1187 
1188  /// @}
1189  /// @} group chrono
1190 
1191  // Clocks.
1192 
1193  // Why nanosecond resolution as the default?
1194  // Why have std::system_clock always count in the highest
1195  // resolution (ie nanoseconds), even if on some OSes the low 3
1196  // or 9 decimal digits will be always zero? This allows later
1197  // implementations to change the system_clock::now()
1198  // implementation any time to provide better resolution without
1199  // changing function signature or units.
1200 
1201  // To support the (forward) evolution of the library's defined
1202  // clocks, wrap inside inline namespace so that the current
1203  // defintions of system_clock, steady_clock, and
1204  // high_resolution_clock types are uniquely mangled. This way, new
1205  // code can use the latests clocks, while the library can contain
1206  // compatibility definitions for previous versions. At some
1207  // point, when these clocks settle down, the inlined namespaces
1208  // can be removed. XXX GLIBCXX_ABI Deprecated
1209  inline namespace _V2 {
1210 
1211  /**
1212  * @brief System clock.
1213  *
1214  * Time returned represents wall time from the system-wide clock.
1215  * @ingroup chrono
1216  */
1218  {
1219  typedef chrono::nanoseconds duration;
1220  typedef duration::rep rep;
1221  typedef duration::period period;
1223 
1224  static_assert(system_clock::duration::min()
1225  < system_clock::duration::zero(),
1226  "a clock's minimum duration cannot be less than its epoch");
1227 
1228  static constexpr bool is_steady = false;
1229 
1230  static time_point
1231  now() noexcept;
1232 
1233  // Map to C API
1234  static std::time_t
1235  to_time_t(const time_point& __t) noexcept
1236  {
1237  return std::time_t(duration_cast<chrono::seconds>
1238  (__t.time_since_epoch()).count());
1239  }
1240 
1241  static time_point
1242  from_time_t(std::time_t __t) noexcept
1243  {
1245  return time_point_cast<system_clock::duration>
1246  (__from(chrono::seconds(__t)));
1247  }
1248  };
1249 
1250 
1251  /**
1252  * @brief Monotonic clock
1253  *
1254  * Time returned has the property of only increasing at a uniform rate.
1255  * @ingroup chrono
1256  */
1258  {
1259  typedef chrono::nanoseconds duration;
1260  typedef duration::rep rep;
1261  typedef duration::period period;
1263 
1264  static constexpr bool is_steady = true;
1265 
1266  static time_point
1267  now() noexcept;
1268  };
1269 
1270 
1271  /**
1272  * @brief Highest-resolution clock
1273  *
1274  * This is the clock "with the shortest tick period." Alias to
1275  * std::system_clock until higher-than-nanosecond definitions
1276  * become feasible.
1277  * @ingroup chrono
1278  */
1280 
1281  } // end inline namespace _V2
1282 
1283 #if __cplusplus >= 202002L
1284  /// @addtogroup chrono
1285  /// @{
1286  template<typename _Duration>
1289  using sys_days = sys_time<days>;
1290 
1291  using file_clock = ::std::filesystem::__file_clock;
1292 
1293  template<typename _Duration>
1295 
1296  template<> struct is_clock<system_clock> : true_type { };
1297  template<> struct is_clock<steady_clock> : true_type { };
1298  template<> struct is_clock<file_clock> : true_type { };
1299 
1300  template<> inline constexpr bool is_clock_v<system_clock> = true;
1301  template<> inline constexpr bool is_clock_v<steady_clock> = true;
1302  template<> inline constexpr bool is_clock_v<file_clock> = true;
1303  /// @}
1304 #endif // C++20
1305  } // namespace chrono
1306 
1307 #if __cplusplus >= 201402L
1308 #define __cpp_lib_chrono_udls 201304L
1309 
1310  inline namespace literals
1311  {
1312  /** ISO C++ 2014 namespace for suffixes for duration literals.
1313  *
1314  * These suffixes can be used to create `chrono::duration` values with
1315  * tick periods of hours, minutes, seconds, milliseconds, microseconds
1316  * or nanoseconds. For example, `std::chrono::seconds(5)` can be written
1317  * as `5s` after making the suffix visible in the current scope.
1318  * The suffixes can be made visible by a using-directive or
1319  * using-declaration such as:
1320  * - `using namespace std::chrono_literals;`
1321  * - `using namespace std::literals;`
1322  * - `using namespace std::chrono;`
1323  * - `using namespace std;`
1324  * - `using std::chrono_literals::operator""s;`
1325  *
1326  * The result of these suffixes on an integer literal is one of the
1327  * standard typedefs such as `std::chrono::hours`.
1328  * The result on a floating-point literal is a duration type with the
1329  * specified tick period and an unspecified floating-point representation,
1330  * for example `1.5e2ms` might be equivalent to
1331  * `chrono::duration<long double, chrono::milli>(1.5e2)`.
1332  *
1333  * @since C+14
1334  * @ingroup chrono
1335  */
1336  inline namespace chrono_literals
1337  {
1338  /// @addtogroup chrono
1339  /// @{
1340 
1341 #pragma GCC diagnostic push
1342 #pragma GCC diagnostic ignored "-Wliteral-suffix"
1343  /// @cond undocumented
1344  template<typename _Dur, char... _Digits>
1345  constexpr _Dur __check_overflow()
1346  {
1347  using _Val = __parse_int::_Parse_int<_Digits...>;
1348  constexpr typename _Dur::rep __repval = _Val::value;
1349  static_assert(__repval >= 0 && __repval == _Val::value,
1350  "literal value cannot be represented by duration type");
1351  return _Dur(__repval);
1352  }
1353  /// @endcond
1354 
1355  /// Literal suffix for durations representing non-integer hours
1356  constexpr chrono::duration<long double, ratio<3600,1>>
1357  operator""h(long double __hours)
1358  { return chrono::duration<long double, ratio<3600,1>>{__hours}; }
1359 
1360  /// Literal suffix for durations of type `std::chrono::hours`
1361  template <char... _Digits>
1362  constexpr chrono::hours
1363  operator""h()
1364  { return __check_overflow<chrono::hours, _Digits...>(); }
1365 
1366  /// Literal suffix for durations representing non-integer minutes
1368  operator""min(long double __mins)
1369  { return chrono::duration<long double, ratio<60,1>>{__mins}; }
1370 
1371  /// Literal suffix for durations of type `std::chrono::minutes`
1372  template <char... _Digits>
1373  constexpr chrono::minutes
1374  operator""min()
1375  { return __check_overflow<chrono::minutes, _Digits...>(); }
1376 
1377  /// Literal suffix for durations representing non-integer seconds
1379  operator""s(long double __secs)
1380  { return chrono::duration<long double>{__secs}; }
1381 
1382  /// Literal suffix for durations of type `std::chrono::seconds`
1383  template <char... _Digits>
1384  constexpr chrono::seconds
1385  operator""s()
1386  { return __check_overflow<chrono::seconds, _Digits...>(); }
1387 
1388  /// Literal suffix for durations representing non-integer milliseconds
1390  operator""ms(long double __msecs)
1391  { return chrono::duration<long double, milli>{__msecs}; }
1392 
1393  /// Literal suffix for durations of type `std::chrono::milliseconds`
1394  template <char... _Digits>
1395  constexpr chrono::milliseconds
1396  operator""ms()
1397  { return __check_overflow<chrono::milliseconds, _Digits...>(); }
1398 
1399  /// Literal suffix for durations representing non-integer microseconds
1401  operator""us(long double __usecs)
1402  { return chrono::duration<long double, micro>{__usecs}; }
1403 
1404  /// Literal suffix for durations of type `std::chrono::microseconds`
1405  template <char... _Digits>
1406  constexpr chrono::microseconds
1407  operator""us()
1408  { return __check_overflow<chrono::microseconds, _Digits...>(); }
1409 
1410  /// Literal suffix for durations representing non-integer nanoseconds
1412  operator""ns(long double __nsecs)
1413  { return chrono::duration<long double, nano>{__nsecs}; }
1414 
1415  /// Literal suffix for durations of type `std::chrono::nanoseconds`
1416  template <char... _Digits>
1417  constexpr chrono::nanoseconds
1418  operator""ns()
1419  { return __check_overflow<chrono::nanoseconds, _Digits...>(); }
1420 
1421 #pragma GCC diagnostic pop
1422  /// @}
1423  } // inline namespace chrono_literals
1424  } // inline namespace literals
1425 
1426  namespace chrono
1427  {
1428  using namespace literals::chrono_literals;
1429  } // namespace chrono
1430 #endif // C++14
1431 
1432 #if __cplusplus >= 201703L
1433  namespace filesystem
1434  {
1435  struct __file_clock
1436  {
1437  using duration = chrono::nanoseconds;
1438  using rep = duration::rep;
1439  using period = duration::period;
1440  using time_point = chrono::time_point<__file_clock>;
1441  static constexpr bool is_steady = false;
1442 
1443  static time_point
1444  now() noexcept
1445  { return _S_from_sys(chrono::system_clock::now()); }
1446 
1447 #if __cplusplus > 201703L
1448  template<typename _Dur>
1449  static
1450  chrono::file_time<_Dur>
1451  from_sys(const chrono::sys_time<_Dur>& __t) noexcept
1452  { return _S_from_sys(__t); }
1453 
1454  // For internal use only
1455  template<typename _Dur>
1456  static
1457  chrono::sys_time<_Dur>
1458  to_sys(const chrono::file_time<_Dur>& __t) noexcept
1459  { return _S_to_sys(__t); }
1460 #endif // C++20
1461 
1462  private:
1463  using __sys_clock = chrono::system_clock;
1464 
1465  // This clock's (unspecified) epoch is 2174-01-01 00:00:00 UTC.
1466  // A signed 64-bit duration with nanosecond resolution gives roughly
1467  // +/- 292 years, which covers the 1901-2446 date range for ext4.
1468  static constexpr chrono::seconds _S_epoch_diff{6437664000};
1469 
1470  protected:
1471  // For internal use only
1472  template<typename _Dur>
1473  static
1474  chrono::time_point<__file_clock, _Dur>
1475  _S_from_sys(const chrono::time_point<__sys_clock, _Dur>& __t) noexcept
1476  {
1477  using __file_time = chrono::time_point<__file_clock, _Dur>;
1478  return __file_time{__t.time_since_epoch()} - _S_epoch_diff;
1479  }
1480 
1481  // For internal use only
1482  template<typename _Dur>
1483  static
1484  chrono::time_point<__sys_clock, _Dur>
1485  _S_to_sys(const chrono::time_point<__file_clock, _Dur>& __t) noexcept
1486  {
1487  using __sys_time = chrono::time_point<__sys_clock, _Dur>;
1488  return __sys_time{__t.time_since_epoch()} + _S_epoch_diff;
1489  }
1490  };
1491  } // namespace filesystem
1492 #endif // C++17
1493 
1494 _GLIBCXX_END_NAMESPACE_VERSION
1495 } // namespace std
1496 
1497 #endif // C++11
1498 
1499 #endif //_GLIBCXX_CHRONO_H
constexpr duration< __common_rep_t< _Rep1, __disable_if_is_duration< _Rep2 > >, _Period > operator%(const duration< _Rep1, _Period > &__d, const _Rep2 &__s)
Definition: chrono.h:770
constexpr bool operator==(const duration< _Rep1, _Period1 > &__lhs, const duration< _Rep2, _Period2 > &__rhs)
Definition: chrono.h:801
duration< int64_t > seconds
seconds
Definition: chrono.h:888
constexpr enable_if_t< numeric_limits< _Rep >::is_signed, duration< _Rep, _Period > > abs(duration< _Rep, _Period > __d)
Definition: chrono.h:435
constexpr bool operator<=(const duration< _Rep1, _Period1 > &__lhs, const duration< _Rep2, _Period2 > &__rhs)
Definition: chrono.h:846
duration< int64_t, ratio< 3600 > > hours
hours
Definition: chrono.h:894
duration< int64_t, milli > milliseconds
milliseconds
Definition: chrono.h:885
constexpr __enable_if_is_duration< _ToDur > duration_cast(const duration< _Rep, _Period > &__d)
Definition: chrono.h:262
duration< int64_t, micro > microseconds
microseconds
Definition: chrono.h:882
constexpr bool operator>=(const duration< _Rep1, _Period1 > &__lhs, const duration< _Rep2, _Period2 > &__rhs)
Definition: chrono.h:860
constexpr bool operator!=(const duration< _Rep1, _Period1 > &__lhs, const duration< _Rep2, _Period2 > &__rhs)
Definition: chrono.h:838
duration< int64_t, nano > nanoseconds
nanoseconds
Definition: chrono.h:879
constexpr time_point< _Clock, typename common_type< duration< _Rep1, _Period1 >, _Dur2 >::type > operator+(const duration< _Rep1, _Period1 > &__lhs, const time_point< _Clock, _Dur2 > &__rhs)
Adjust a time point forwards by the given duration.
Definition: chrono.h:1107
constexpr time_point< _Clock, typename common_type< _Dur1, duration< _Rep2, _Period2 > >::type > operator+(const time_point< _Clock, _Dur1 > &__lhs, const duration< _Rep2, _Period2 > &__rhs)
Definition: chrono.h:1093
constexpr duration< __common_rep_t< _Rep2, _Rep1 >, _Period > operator*(const _Rep1 &__s, const duration< _Rep2, _Period > &__d)
Definition: chrono.h:741
constexpr __enable_if_is_duration< _ToDur > floor(const duration< _Rep, _Period > &__d)
Definition: chrono.h:364
constexpr common_type< duration< _Rep1, _Period1 >, duration< _Rep2, _Period2 > >::type operator-(const duration< _Rep1, _Period1 > &__lhs, const duration< _Rep2, _Period2 > &__rhs)
The difference between two durations.
Definition: chrono.h:701
duration< int64_t, ratio< 60 > > minutes
minutes
Definition: chrono.h:891
constexpr __enable_if_is_duration< _ToDur > ceil(const duration< _Rep, _Period > &__d)
Definition: chrono.h:384
constexpr common_type< duration< _Rep1, _Period1 >, duration< _Rep2, _Period2 > >::type operator+(const duration< _Rep1, _Period1 > &__lhs, const duration< _Rep2, _Period2 > &__rhs)
Definition: chrono.h:687
constexpr bool operator<(const duration< _Rep1, _Period1 > &__lhs, const duration< _Rep2, _Period2 > &__rhs)
Definition: chrono.h:813
constexpr enable_if_t< __and_< __is_duration< _ToDur >, __not_< treat_as_floating_point< typename _ToDur::rep > > >::value, _ToDur > round(const duration< _Rep, _Period > &__d)
Definition: chrono.h:409
constexpr duration< __common_rep_t< _Rep1, __disable_if_is_duration< _Rep2 > >, _Period > operator/(const duration< _Rep1, _Period > &__d, const _Rep2 &__s)
Definition: chrono.h:747
constexpr bool operator>(const duration< _Rep1, _Period1 > &__lhs, const duration< _Rep2, _Period2 > &__rhs)
Definition: chrono.h:853
constexpr duration< __common_rep_t< _Rep1, _Rep2 >, _Period > operator*(const duration< _Rep1, _Period > &__d, const _Rep2 &__s)
Definition: chrono.h:732
constexpr __enable_if_t< __is_duration< _ToDur >::value, time_point< _Clock, _ToDur > > time_point_cast(const time_point< _Clock, _Dur > &__t)
Definition: chrono.h:1010
typename __ratio_divide< _R1, _R2 >::type ratio_divide
ratio_divide
Definition: ratio:353
void void_t
A metafunction that always yields void, used for detecting valid types.
Definition: type_traits:2630
integral_constant< bool, true > true_type
The type used as a compile-time boolean with true value.
Definition: type_traits:82
typename common_type< _Tp... >::type common_type_t
Alias template for common_type.
Definition: type_traits:2616
integral_constant< bool, false > false_type
The type used as a compile-time boolean with false value.
Definition: type_traits:85
typename enable_if< _Cond, _Tp >::type enable_if_t
Alias template for enable_if.
Definition: type_traits:2608
constexpr const _Tp & min(const _Tp &, const _Tp &)
This does what you think it does.
Definition: stl_algobase.h:230
ISO C++ entities toplevel namespace is std.
concept same_as
[concept.same], concept same_as
Definition: concepts:63
Properties of fundamental types.
Definition: limits:313
static constexpr _Tp max() noexcept
Definition: limits:321
static constexpr _Tp lowest() noexcept
Definition: limits:327
Provides compile-time rational arithmetic.
Definition: ratio:267
integral_constant
Definition: type_traits:63
is_floating_point
Definition: type_traits:445
is_convertible
Definition: type_traits:1484
Define a member typedef type only if a boolean constant is true.
Definition: type_traits:2223
common_type
Definition: type_traits:2259
chrono::duration represents a distance between two points in time
Definition: chrono.h:502
chrono::time_point represents a point in time as measured by a clock
Definition: chrono.h:914
duration_values
Definition: chrono.h:472