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
47namespace 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 {
115 using type = chrono::duration<typename common_type<_Rep>::type,
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 {
123 using type = chrono::duration<typename common_type<_Rep>::type,
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>>
158 { using type = 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>>
163 { using 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
231 : std::false_type
232 { };
233
234 template<typename _Rep, typename _Period>
235 struct __is_duration<duration<_Rep, _Period>>
236 : std::true_type
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>
262 duration_cast(const duration<_Rep, _Period>& __d)
263 {
264 typedef typename _ToDur::period __to_period;
265 typedef typename _ToDur::rep __to_rep;
266 typedef ratio_divide<_Period, __to_period> __cf;
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>
285 struct treat_as_floating_point
286 : is_floating_point<_Rep>
287 { };
288
289#if __cplusplus > 201402L
290 template <typename _Rep>
291 inline constexpr bool treat_as_floating_point_v =
292 treat_as_floating_point<_Rep>::value;
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>
364 floor(const duration<_Rep, _Period>& __d)
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>
384 ceil(const duration<_Rep, _Period>& __d)
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>
409 round(const duration<_Rep, _Period>& __d)
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>>
435 abs(duration<_Rep, _Period> __d)
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>
471 struct duration_values
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
490 : std::false_type
491 { };
492
493 template<intmax_t _Num, intmax_t _Den>
494 struct __is_ratio<ratio<_Num, _Den>>
495 : std::true_type
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>
509 using __is_float = treat_as_floating_point<_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(m: _R1::num, n: _R2::num),
538 intmax_t __gcd2 = _S_gcd(m: _R1::den, n: _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<
560 is_convertible<const _Rep2&, rep>,
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<
566 is_convertible<const _Rep2&, rep>,
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
583 constexpr duration<typename common_type<rep>::type, period>
584 operator+() const
585 { return duration<typename common_type<rep>::type, period>(__r); }
586
587 constexpr duration<typename common_type<rep>::type, period>
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
644 typename enable_if<!treat_as_floating_point<_Rep2>::value,
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
654 typename enable_if<!treat_as_floating_point<_Rep2>::value,
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>,
686 duration<_Rep2, _Period2>>::type
687 operator+(const duration<_Rep1, _Period1>& __lhs,
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>,
700 duration<_Rep2, _Period2>>::type
701 operator-(const duration<_Rep1, _Period1>& __lhs,
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
721 enable_if<is_convertible<const _Rep2&, _CRep>::value, _CRep>::type;
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 {
734 typedef duration<typename common_type<_Rep1, _Rep2>::type, _Period>
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 {
749 typedef duration<typename common_type<_Rep1, _Rep2>::type, _Period>
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
757 operator/(const duration<_Rep1, _Period1>& __lhs,
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 {
772 typedef duration<typename common_type<_Rep1, _Rep2>::type, _Period>
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
781 operator%(const duration<_Rep1, _Period1>& __lhs,
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
801 operator==(const duration<_Rep1, _Period1>& __lhs,
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
813 operator<(const duration<_Rep1, _Period1>& __lhs,
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 {
830 using __ct = common_type_t<duration<_Rep1, _Period1>,
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
838 operator!=(const duration<_Rep1, _Period1>& __lhs,
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
846 operator<=(const duration<_Rep1, _Period1>& __lhs,
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
853 operator>(const duration<_Rep1, _Period1>& __lhs,
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
860 operator>=(const duration<_Rep1, _Period1>& __lhs,
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
872 static_assert(std::numeric_limits<unsigned long long>::digits >= 64,
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
879 using nanoseconds = duration<_GLIBCXX_CHRONO_INT64_T, nano>;
880
881 /// microseconds
882 using microseconds = duration<_GLIBCXX_CHRONO_INT64_T, micro>;
883
884 /// milliseconds
885 using milliseconds = duration<_GLIBCXX_CHRONO_INT64_T, milli>;
886
887 /// seconds
888 using seconds = duration<_GLIBCXX_CHRONO_INT64_T>;
889
890 /// minutes
891 using minutes = duration<_GLIBCXX_CHRONO_INT64_T, ratio< 60>>;
892
893 /// hours
894 using hours = duration<_GLIBCXX_CHRONO_INT64_T, ratio<3600>>;
895
896#if __cplusplus > 201703L
897 /// days
898 using days = duration<_GLIBCXX_CHRONO_INT64_T, ratio<86400>>;
899
900 /// weeks
901 using weeks = duration<_GLIBCXX_CHRONO_INT64_T, ratio<604800>>;
902
903 /// years
904 using years = duration<_GLIBCXX_CHRONO_INT64_T, ratio<31556952>>;
905
906 /// months
907 using months = duration<_GLIBCXX_CHRONO_INT64_T, ratio<2629746>>;
908#endif // C++20
909
910#undef _GLIBCXX_CHRONO_INT64_T
911
912 template<typename _Clock, typename _Dur>
913 class time_point
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>>
1010 time_point_cast(const time_point<_Clock, _Dur>& __t)
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>>
1032 floor(const time_point<_Clock, _Dur>& __tp)
1033 {
1034 return time_point<_Clock, _ToDur>{
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>>
1053 ceil(const time_point<_Clock, _Dur>& __tp)
1054 {
1055 return time_point<_Clock, _ToDur>{
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>>
1078 round(const time_point<_Clock, _Dur>& __tp)
1079 {
1080 return time_point<_Clock, _ToDur>{
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,
1092 typename common_type<_Dur1, duration<_Rep2, _Period2>>::type>
1093 operator+(const time_point<_Clock, _Dur1>& __lhs,
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>
1107 operator+(const duration<_Rep1, _Period1>& __lhs,
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,
1120 typename common_type<_Dur1, duration<_Rep2, _Period2>>::type>
1121 operator-(const time_point<_Clock, _Dur1>& __lhs,
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
1133 operator-(const time_point<_Clock, _Dur1>& __lhs,
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 */
1217 struct system_clock
1218 {
1219 typedef chrono::nanoseconds duration;
1220 typedef duration::rep rep;
1221 typedef duration::period period;
1222 typedef chrono::time_point<system_clock, duration> time_point;
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 (d: __t.time_since_epoch()).count());
1239 }
1240
1241 static time_point
1242 from_time_t(std::time_t __t) noexcept
1243 {
1244 typedef chrono::time_point<system_clock, seconds> __from;
1245 return time_point_cast<system_clock::duration>
1246 (t: __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 */
1257 struct steady_clock
1258 {
1259 typedef chrono::nanoseconds duration;
1260 typedef duration::rep rep;
1261 typedef duration::period period;
1262 typedef chrono::time_point<steady_clock, duration> time_point;
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 */
1279 using high_resolution_clock = system_clock;
1280
1281 } // end inline namespace _V2
1282
1283#if __cplusplus >= 202002L
1284 /// @addtogroup chrono
1285 /// @{
1286 template<typename _Duration>
1287 using sys_time = time_point<system_clock, _Duration>;
1288 using sys_seconds = sys_time<seconds>;
1289 using sys_days = sys_time<days>;
1290
1291 using file_clock = ::std::filesystem::__file_clock;
1292
1293 template<typename _Duration>
1294 using file_time = time_point<file_clock, _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
1367 constexpr chrono::duration<long double, ratio<60,1>>
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
1378 constexpr chrono::duration<long double>
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
1389 constexpr chrono::duration<long double, milli>
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
1400 constexpr chrono::duration<long double, micro>
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
1411 constexpr chrono::duration<long double, nano>
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(t: 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
1500