libstdc++
chrono
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1 // <chrono> -*- C++ -*-
2 
3 // Copyright (C) 2008-2019 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/chrono
26  * This is a Standard C++ Library header.
27  */
28 
29 #ifndef _GLIBCXX_CHRONO
30 #define _GLIBCXX_CHRONO 1
31 
32 #pragma GCC system_header
33 
34 #if __cplusplus < 201103L
35 # include <bits/c++0x_warning.h>
36 #else
37 
38 #include <ratio>
39 #include <type_traits>
40 #include <limits>
41 #include <ctime>
42 #include <bits/parse_numbers.h> // for literals support.
43 
44 namespace std _GLIBCXX_VISIBILITY(default)
45 {
46 _GLIBCXX_BEGIN_NAMESPACE_VERSION
47 
48  /**
49  * @defgroup chrono Time
50  * @ingroup utilities
51  *
52  * Classes and functions for time.
53  * @{
54  */
55 
56  /** @namespace std::chrono
57  * @brief ISO C++ 2011 entities sub-namespace for time and date.
58  */
59  namespace chrono
60  {
61  template<typename _Rep, typename _Period = ratio<1>>
62  struct duration;
63 
64  template<typename _Clock, typename _Dur = typename _Clock::duration>
65  struct time_point;
66  }
67 
68  // 20.11.4.3 specialization of common_type (for duration, sfinae-friendly)
69 
70  template<typename _CT, typename _Period1, typename _Period2>
71  struct __duration_common_type_wrapper
72  {
73  private:
74  typedef __static_gcd<_Period1::num, _Period2::num> __gcd_num;
75  typedef __static_gcd<_Period1::den, _Period2::den> __gcd_den;
76  typedef typename _CT::type __cr;
77  typedef ratio<__gcd_num::value,
78  (_Period1::den / __gcd_den::value) * _Period2::den> __r;
79  public:
80  typedef __success_type<chrono::duration<__cr, __r>> type;
81  };
82 
83  template<typename _Period1, typename _Period2>
84  struct __duration_common_type_wrapper<__failure_type, _Period1, _Period2>
85  { typedef __failure_type type; };
86 
87  template<typename _Rep1, typename _Period1, typename _Rep2, typename _Period2>
88  struct common_type<chrono::duration<_Rep1, _Period1>,
89  chrono::duration<_Rep2, _Period2>>
90  : public __duration_common_type_wrapper<typename __member_type_wrapper<
91  common_type<_Rep1, _Rep2>>::type, _Period1, _Period2>::type
92  { };
93 
94  // 20.11.4.3 specialization of common_type (for time_point, sfinae-friendly)
95 
96  template<typename _CT, typename _Clock>
97  struct __timepoint_common_type_wrapper
98  {
99  typedef __success_type<chrono::time_point<_Clock, typename _CT::type>>
100  type;
101  };
102 
103  template<typename _Clock>
104  struct __timepoint_common_type_wrapper<__failure_type, _Clock>
105  { typedef __failure_type type; };
106 
107  template<typename _Clock, typename _Duration1, typename _Duration2>
108  struct common_type<chrono::time_point<_Clock, _Duration1>,
109  chrono::time_point<_Clock, _Duration2>>
110  : public __timepoint_common_type_wrapper<typename __member_type_wrapper<
111  common_type<_Duration1, _Duration2>>::type, _Clock>::type
112  { };
113 
114  namespace chrono
115  {
116  // Primary template for duration_cast impl.
117  template<typename _ToDur, typename _CF, typename _CR,
118  bool _NumIsOne = false, bool _DenIsOne = false>
119  struct __duration_cast_impl
120  {
121  template<typename _Rep, typename _Period>
122  static constexpr _ToDur
123  __cast(const duration<_Rep, _Period>& __d)
124  {
125  typedef typename _ToDur::rep __to_rep;
126  return _ToDur(static_cast<__to_rep>(static_cast<_CR>(__d.count())
127  * static_cast<_CR>(_CF::num)
128  / static_cast<_CR>(_CF::den)));
129  }
130  };
131 
132  template<typename _ToDur, typename _CF, typename _CR>
133  struct __duration_cast_impl<_ToDur, _CF, _CR, true, true>
134  {
135  template<typename _Rep, typename _Period>
136  static constexpr _ToDur
137  __cast(const duration<_Rep, _Period>& __d)
138  {
139  typedef typename _ToDur::rep __to_rep;
140  return _ToDur(static_cast<__to_rep>(__d.count()));
141  }
142  };
143 
144  template<typename _ToDur, typename _CF, typename _CR>
145  struct __duration_cast_impl<_ToDur, _CF, _CR, true, false>
146  {
147  template<typename _Rep, typename _Period>
148  static constexpr _ToDur
149  __cast(const duration<_Rep, _Period>& __d)
150  {
151  typedef typename _ToDur::rep __to_rep;
152  return _ToDur(static_cast<__to_rep>(
153  static_cast<_CR>(__d.count()) / static_cast<_CR>(_CF::den)));
154  }
155  };
156 
157  template<typename _ToDur, typename _CF, typename _CR>
158  struct __duration_cast_impl<_ToDur, _CF, _CR, false, true>
159  {
160  template<typename _Rep, typename _Period>
161  static constexpr _ToDur
162  __cast(const duration<_Rep, _Period>& __d)
163  {
164  typedef typename _ToDur::rep __to_rep;
165  return _ToDur(static_cast<__to_rep>(
166  static_cast<_CR>(__d.count()) * static_cast<_CR>(_CF::num)));
167  }
168  };
169 
170  template<typename _Tp>
171  struct __is_duration
172  : std::false_type
173  { };
174 
175  template<typename _Rep, typename _Period>
176  struct __is_duration<duration<_Rep, _Period>>
177  : std::true_type
178  { };
179 
180  template<typename _Tp>
181  using __enable_if_is_duration
182  = typename enable_if<__is_duration<_Tp>::value, _Tp>::type;
183 
184  template<typename _Tp>
185  using __disable_if_is_duration
186  = typename enable_if<!__is_duration<_Tp>::value, _Tp>::type;
187 
188  /// duration_cast
189  template<typename _ToDur, typename _Rep, typename _Period>
190  constexpr __enable_if_is_duration<_ToDur>
191  duration_cast(const duration<_Rep, _Period>& __d)
192  {
193  typedef typename _ToDur::period __to_period;
194  typedef typename _ToDur::rep __to_rep;
195  typedef ratio_divide<_Period, __to_period> __cf;
196  typedef typename common_type<__to_rep, _Rep, intmax_t>::type
197  __cr;
198  typedef __duration_cast_impl<_ToDur, __cf, __cr,
199  __cf::num == 1, __cf::den == 1> __dc;
200  return __dc::__cast(__d);
201  }
202 
203  /// treat_as_floating_point
204  template<typename _Rep>
205  struct treat_as_floating_point
206  : is_floating_point<_Rep>
207  { };
208 
209 #if __cplusplus > 201402L
210  template <typename _Rep>
211  inline constexpr bool treat_as_floating_point_v =
212  treat_as_floating_point<_Rep>::value;
213 #endif // C++17
214 
215 #if __cplusplus >= 201703L
216 # define __cpp_lib_chrono 201611
217 
218  template<typename _ToDur, typename _Rep, typename _Period>
219  constexpr __enable_if_is_duration<_ToDur>
220  floor(const duration<_Rep, _Period>& __d)
221  {
222  auto __to = chrono::duration_cast<_ToDur>(__d);
223  if (__to > __d)
224  return __to - _ToDur{1};
225  return __to;
226  }
227 
228  template<typename _ToDur, typename _Rep, typename _Period>
229  constexpr __enable_if_is_duration<_ToDur>
230  ceil(const duration<_Rep, _Period>& __d)
231  {
232  auto __to = chrono::duration_cast<_ToDur>(__d);
233  if (__to < __d)
234  return __to + _ToDur{1};
235  return __to;
236  }
237 
238  template <typename _ToDur, typename _Rep, typename _Period>
239  constexpr enable_if_t<
240  __and_<__is_duration<_ToDur>,
241  __not_<treat_as_floating_point<typename _ToDur::rep>>>::value,
242  _ToDur>
243  round(const duration<_Rep, _Period>& __d)
244  {
245  _ToDur __t0 = chrono::floor<_ToDur>(__d);
246  _ToDur __t1 = __t0 + _ToDur{1};
247  auto __diff0 = __d - __t0;
248  auto __diff1 = __t1 - __d;
249  if (__diff0 == __diff1)
250  {
251  if (__t0.count() & 1)
252  return __t1;
253  return __t0;
254  }
255  else if (__diff0 < __diff1)
256  return __t0;
257  return __t1;
258  }
259 
260  template<typename _Rep, typename _Period>
261  constexpr
262  enable_if_t<numeric_limits<_Rep>::is_signed, duration<_Rep, _Period>>
263  abs(duration<_Rep, _Period> __d)
264  {
265  if (__d >= __d.zero())
266  return __d;
267  return -__d;
268  }
269 #endif // C++17
270 
271  /// duration_values
272  template<typename _Rep>
273  struct duration_values
274  {
275  static constexpr _Rep
276  zero() noexcept
277  { return _Rep(0); }
278 
279  static constexpr _Rep
280  max() noexcept
281  { return numeric_limits<_Rep>::max(); }
282 
283  static constexpr _Rep
284  min() noexcept
285  { return numeric_limits<_Rep>::lowest(); }
286  };
287 
288  template<typename _Tp>
289  struct __is_ratio
290  : std::false_type
291  { };
292 
293  template<intmax_t _Num, intmax_t _Den>
294  struct __is_ratio<ratio<_Num, _Den>>
295  : std::true_type
296  { };
297 
298  /// duration
299  template<typename _Rep, typename _Period>
300  struct duration
301  {
302  private:
303  template<typename _Rep2>
304  using __is_float = treat_as_floating_point<_Rep2>;
305 
306  // _Period2 is an exact multiple of _Period
307  template<typename _Period2>
308  using __is_harmonic
309  = __bool_constant<ratio_divide<_Period2, _Period>::den == 1>;
310 
311  public:
312 
313  typedef _Rep rep;
314  typedef _Period period;
315 
316  static_assert(!__is_duration<_Rep>::value, "rep cannot be a duration");
317  static_assert(__is_ratio<_Period>::value,
318  "period must be a specialization of ratio");
319  static_assert(_Period::num > 0, "period must be positive");
320 
321  // 20.11.5.1 construction / copy / destroy
322  constexpr duration() = default;
323 
324  duration(const duration&) = default;
325 
326  // _GLIBCXX_RESOLVE_LIB_DEFECTS
327  // 3050. Conversion specification problem in chrono::duration
328  template<typename _Rep2, typename = _Require<
329  is_convertible<const _Rep2&, rep>,
330  __or_<__is_float<rep>, __not_<__is_float<_Rep2>>>>>
331  constexpr explicit duration(const _Rep2& __rep)
332  : __r(static_cast<rep>(__rep)) { }
333 
334  template<typename _Rep2, typename _Period2, typename = _Require<
335  __or_<__is_float<rep>,
336  __and_<__is_harmonic<_Period2>,
337  __not_<__is_float<_Rep2>>>>>>
338  constexpr duration(const duration<_Rep2, _Period2>& __d)
339  : __r(duration_cast<duration>(__d).count()) { }
340 
341  ~duration() = default;
342  duration& operator=(const duration&) = default;
343 
344  // 20.11.5.2 observer
345  constexpr rep
346  count() const
347  { return __r; }
348 
349  // 20.11.5.3 arithmetic
350  constexpr duration
351  operator+() const
352  { return *this; }
353 
354  constexpr duration
355  operator-() const
356  { return duration(-__r); }
357 
358  _GLIBCXX17_CONSTEXPR duration&
359  operator++()
360  {
361  ++__r;
362  return *this;
363  }
364 
365  _GLIBCXX17_CONSTEXPR duration
366  operator++(int)
367  { return duration(__r++); }
368 
369  _GLIBCXX17_CONSTEXPR duration&
370  operator--()
371  {
372  --__r;
373  return *this;
374  }
375 
376  _GLIBCXX17_CONSTEXPR duration
377  operator--(int)
378  { return duration(__r--); }
379 
380  _GLIBCXX17_CONSTEXPR duration&
381  operator+=(const duration& __d)
382  {
383  __r += __d.count();
384  return *this;
385  }
386 
387  _GLIBCXX17_CONSTEXPR duration&
388  operator-=(const duration& __d)
389  {
390  __r -= __d.count();
391  return *this;
392  }
393 
394  _GLIBCXX17_CONSTEXPR duration&
395  operator*=(const rep& __rhs)
396  {
397  __r *= __rhs;
398  return *this;
399  }
400 
401  _GLIBCXX17_CONSTEXPR duration&
402  operator/=(const rep& __rhs)
403  {
404  __r /= __rhs;
405  return *this;
406  }
407 
408  // DR 934.
409  template<typename _Rep2 = rep>
410  _GLIBCXX17_CONSTEXPR
411  typename enable_if<!treat_as_floating_point<_Rep2>::value,
412  duration&>::type
413  operator%=(const rep& __rhs)
414  {
415  __r %= __rhs;
416  return *this;
417  }
418 
419  template<typename _Rep2 = rep>
420  _GLIBCXX17_CONSTEXPR
421  typename enable_if<!treat_as_floating_point<_Rep2>::value,
422  duration&>::type
423  operator%=(const duration& __d)
424  {
425  __r %= __d.count();
426  return *this;
427  }
428 
429  // 20.11.5.4 special values
430  static constexpr duration
431  zero() noexcept
432  { return duration(duration_values<rep>::zero()); }
433 
434  static constexpr duration
435  min() noexcept
436  { return duration(duration_values<rep>::min()); }
437 
438  static constexpr duration
439  max() noexcept
440  { return duration(duration_values<rep>::max()); }
441 
442  private:
443  rep __r;
444  };
445 
446  template<typename _Rep1, typename _Period1,
447  typename _Rep2, typename _Period2>
448  constexpr typename common_type<duration<_Rep1, _Period1>,
449  duration<_Rep2, _Period2>>::type
450  operator+(const duration<_Rep1, _Period1>& __lhs,
451  const duration<_Rep2, _Period2>& __rhs)
452  {
453  typedef duration<_Rep1, _Period1> __dur1;
454  typedef duration<_Rep2, _Period2> __dur2;
455  typedef typename common_type<__dur1,__dur2>::type __cd;
456  return __cd(__cd(__lhs).count() + __cd(__rhs).count());
457  }
458 
459  template<typename _Rep1, typename _Period1,
460  typename _Rep2, typename _Period2>
461  constexpr typename common_type<duration<_Rep1, _Period1>,
462  duration<_Rep2, _Period2>>::type
463  operator-(const duration<_Rep1, _Period1>& __lhs,
464  const duration<_Rep2, _Period2>& __rhs)
465  {
466  typedef duration<_Rep1, _Period1> __dur1;
467  typedef duration<_Rep2, _Period2> __dur2;
468  typedef typename common_type<__dur1,__dur2>::type __cd;
469  return __cd(__cd(__lhs).count() - __cd(__rhs).count());
470  }
471 
472  // SFINAE helper to obtain common_type<_Rep1, _Rep2> only if _Rep2
473  // is implicitly convertible to it.
474  // _GLIBCXX_RESOLVE_LIB_DEFECTS
475  // 3050. Conversion specification problem in chrono::duration constructor
476  template<typename _Rep1, typename _Rep2,
477  typename _CRep = typename common_type<_Rep1, _Rep2>::type>
478  using __common_rep_t = typename
479  enable_if<is_convertible<const _Rep2&, _CRep>::value, _CRep>::type;
480 
481  template<typename _Rep1, typename _Period, typename _Rep2>
482  constexpr duration<__common_rep_t<_Rep1, _Rep2>, _Period>
483  operator*(const duration<_Rep1, _Period>& __d, const _Rep2& __s)
484  {
485  typedef duration<typename common_type<_Rep1, _Rep2>::type, _Period>
486  __cd;
487  return __cd(__cd(__d).count() * __s);
488  }
489 
490  template<typename _Rep1, typename _Rep2, typename _Period>
491  constexpr duration<__common_rep_t<_Rep2, _Rep1>, _Period>
492  operator*(const _Rep1& __s, const duration<_Rep2, _Period>& __d)
493  { return __d * __s; }
494 
495  template<typename _Rep1, typename _Period, typename _Rep2>
496  constexpr
497  duration<__common_rep_t<_Rep1, __disable_if_is_duration<_Rep2>>, _Period>
498  operator/(const duration<_Rep1, _Period>& __d, const _Rep2& __s)
499  {
500  typedef duration<typename common_type<_Rep1, _Rep2>::type, _Period>
501  __cd;
502  return __cd(__cd(__d).count() / __s);
503  }
504 
505  template<typename _Rep1, typename _Period1,
506  typename _Rep2, typename _Period2>
507  constexpr typename common_type<_Rep1, _Rep2>::type
508  operator/(const duration<_Rep1, _Period1>& __lhs,
509  const duration<_Rep2, _Period2>& __rhs)
510  {
511  typedef duration<_Rep1, _Period1> __dur1;
512  typedef duration<_Rep2, _Period2> __dur2;
513  typedef typename common_type<__dur1,__dur2>::type __cd;
514  return __cd(__lhs).count() / __cd(__rhs).count();
515  }
516 
517  // DR 934.
518  template<typename _Rep1, typename _Period, typename _Rep2>
519  constexpr
520  duration<__common_rep_t<_Rep1, __disable_if_is_duration<_Rep2>>, _Period>
521  operator%(const duration<_Rep1, _Period>& __d, const _Rep2& __s)
522  {
523  typedef duration<typename common_type<_Rep1, _Rep2>::type, _Period>
524  __cd;
525  return __cd(__cd(__d).count() % __s);
526  }
527 
528  template<typename _Rep1, typename _Period1,
529  typename _Rep2, typename _Period2>
530  constexpr typename common_type<duration<_Rep1, _Period1>,
531  duration<_Rep2, _Period2>>::type
532  operator%(const duration<_Rep1, _Period1>& __lhs,
533  const duration<_Rep2, _Period2>& __rhs)
534  {
535  typedef duration<_Rep1, _Period1> __dur1;
536  typedef duration<_Rep2, _Period2> __dur2;
537  typedef typename common_type<__dur1,__dur2>::type __cd;
538  return __cd(__cd(__lhs).count() % __cd(__rhs).count());
539  }
540 
541  // comparisons
542  template<typename _Rep1, typename _Period1,
543  typename _Rep2, typename _Period2>
544  constexpr bool
545  operator==(const duration<_Rep1, _Period1>& __lhs,
546  const duration<_Rep2, _Period2>& __rhs)
547  {
548  typedef duration<_Rep1, _Period1> __dur1;
549  typedef duration<_Rep2, _Period2> __dur2;
550  typedef typename common_type<__dur1,__dur2>::type __ct;
551  return __ct(__lhs).count() == __ct(__rhs).count();
552  }
553 
554  template<typename _Rep1, typename _Period1,
555  typename _Rep2, typename _Period2>
556  constexpr bool
557  operator<(const duration<_Rep1, _Period1>& __lhs,
558  const duration<_Rep2, _Period2>& __rhs)
559  {
560  typedef duration<_Rep1, _Period1> __dur1;
561  typedef duration<_Rep2, _Period2> __dur2;
562  typedef typename common_type<__dur1,__dur2>::type __ct;
563  return __ct(__lhs).count() < __ct(__rhs).count();
564  }
565 
566  template<typename _Rep1, typename _Period1,
567  typename _Rep2, typename _Period2>
568  constexpr bool
569  operator!=(const duration<_Rep1, _Period1>& __lhs,
570  const duration<_Rep2, _Period2>& __rhs)
571  { return !(__lhs == __rhs); }
572 
573  template<typename _Rep1, typename _Period1,
574  typename _Rep2, typename _Period2>
575  constexpr bool
576  operator<=(const duration<_Rep1, _Period1>& __lhs,
577  const duration<_Rep2, _Period2>& __rhs)
578  { return !(__rhs < __lhs); }
579 
580  template<typename _Rep1, typename _Period1,
581  typename _Rep2, typename _Period2>
582  constexpr bool
583  operator>(const duration<_Rep1, _Period1>& __lhs,
584  const duration<_Rep2, _Period2>& __rhs)
585  { return __rhs < __lhs; }
586 
587  template<typename _Rep1, typename _Period1,
588  typename _Rep2, typename _Period2>
589  constexpr bool
590  operator>=(const duration<_Rep1, _Period1>& __lhs,
591  const duration<_Rep2, _Period2>& __rhs)
592  { return !(__lhs < __rhs); }
593 
594 #ifdef _GLIBCXX_USE_C99_STDINT_TR1
595 # define _GLIBCXX_CHRONO_INT64_T int64_t
596 #elif defined __INT64_TYPE__
597 # define _GLIBCXX_CHRONO_INT64_T __INT64_TYPE__
598 #else
599  static_assert(std::numeric_limits<unsigned long long>::digits >= 64,
600  "Representation type for nanoseconds must have at least 64 bits");
601 # define _GLIBCXX_CHRONO_INT64_T long long
602 #endif
603 
604  /// nanoseconds
605  typedef duration<_GLIBCXX_CHRONO_INT64_T, nano> nanoseconds;
606 
607  /// microseconds
608  typedef duration<_GLIBCXX_CHRONO_INT64_T, micro> microseconds;
609 
610  /// milliseconds
611  typedef duration<_GLIBCXX_CHRONO_INT64_T, milli> milliseconds;
612 
613  /// seconds
614  typedef duration<_GLIBCXX_CHRONO_INT64_T> seconds;
615 
616  /// minutes
617  typedef duration<_GLIBCXX_CHRONO_INT64_T, ratio< 60>> minutes;
618 
619  /// hours
620  typedef duration<_GLIBCXX_CHRONO_INT64_T, ratio<3600>> hours;
621 
622 #undef _GLIBCXX_CHRONO_INT64_T
623 
624  /// time_point
625  template<typename _Clock, typename _Dur>
626  struct time_point
627  {
628  typedef _Clock clock;
629  typedef _Dur duration;
630  typedef typename duration::rep rep;
631  typedef typename duration::period period;
632 
633  constexpr time_point() : __d(duration::zero())
634  { }
635 
636  constexpr explicit time_point(const duration& __dur)
637  : __d(__dur)
638  { }
639 
640  // conversions
641  template<typename _Dur2,
642  typename = _Require<is_convertible<_Dur2, _Dur>>>
643  constexpr time_point(const time_point<clock, _Dur2>& __t)
644  : __d(__t.time_since_epoch())
645  { }
646 
647  // observer
648  constexpr duration
649  time_since_epoch() const
650  { return __d; }
651 
652  // arithmetic
653  _GLIBCXX17_CONSTEXPR time_point&
654  operator+=(const duration& __dur)
655  {
656  __d += __dur;
657  return *this;
658  }
659 
660  _GLIBCXX17_CONSTEXPR time_point&
661  operator-=(const duration& __dur)
662  {
663  __d -= __dur;
664  return *this;
665  }
666 
667  // special values
668  static constexpr time_point
669  min() noexcept
670  { return time_point(duration::min()); }
671 
672  static constexpr time_point
673  max() noexcept
674  { return time_point(duration::max()); }
675 
676  private:
677  duration __d;
678  };
679 
680  /// time_point_cast
681  template<typename _ToDur, typename _Clock, typename _Dur>
682  constexpr typename enable_if<__is_duration<_ToDur>::value,
683  time_point<_Clock, _ToDur>>::type
684  time_point_cast(const time_point<_Clock, _Dur>& __t)
685  {
686  typedef time_point<_Clock, _ToDur> __time_point;
687  return __time_point(duration_cast<_ToDur>(__t.time_since_epoch()));
688  }
689 
690 #if __cplusplus > 201402L
691  template<typename _ToDur, typename _Clock, typename _Dur>
692  constexpr
693  enable_if_t<__is_duration<_ToDur>::value, time_point<_Clock, _ToDur>>
694  floor(const time_point<_Clock, _Dur>& __tp)
695  {
696  return time_point<_Clock, _ToDur>{
697  chrono::floor<_ToDur>(__tp.time_since_epoch())};
698  }
699 
700  template<typename _ToDur, typename _Clock, typename _Dur>
701  constexpr
702  enable_if_t<__is_duration<_ToDur>::value, time_point<_Clock, _ToDur>>
703  ceil(const time_point<_Clock, _Dur>& __tp)
704  {
705  return time_point<_Clock, _ToDur>{
706  chrono::ceil<_ToDur>(__tp.time_since_epoch())};
707  }
708 
709  template<typename _ToDur, typename _Clock, typename _Dur>
710  constexpr enable_if_t<
711  __and_<__is_duration<_ToDur>,
712  __not_<treat_as_floating_point<typename _ToDur::rep>>>::value,
713  time_point<_Clock, _ToDur>>
714  round(const time_point<_Clock, _Dur>& __tp)
715  {
716  return time_point<_Clock, _ToDur>{
717  chrono::round<_ToDur>(__tp.time_since_epoch())};
718  }
719 #endif // C++17
720 
721  template<typename _Clock, typename _Dur1,
722  typename _Rep2, typename _Period2>
723  constexpr time_point<_Clock,
724  typename common_type<_Dur1, duration<_Rep2, _Period2>>::type>
725  operator+(const time_point<_Clock, _Dur1>& __lhs,
726  const duration<_Rep2, _Period2>& __rhs)
727  {
728  typedef duration<_Rep2, _Period2> __dur2;
729  typedef typename common_type<_Dur1,__dur2>::type __ct;
730  typedef time_point<_Clock, __ct> __time_point;
731  return __time_point(__lhs.time_since_epoch() + __rhs);
732  }
733 
734  template<typename _Rep1, typename _Period1,
735  typename _Clock, typename _Dur2>
736  constexpr time_point<_Clock,
737  typename common_type<duration<_Rep1, _Period1>, _Dur2>::type>
738  operator+(const duration<_Rep1, _Period1>& __lhs,
739  const time_point<_Clock, _Dur2>& __rhs)
740  {
741  typedef duration<_Rep1, _Period1> __dur1;
742  typedef typename common_type<__dur1,_Dur2>::type __ct;
743  typedef time_point<_Clock, __ct> __time_point;
744  return __time_point(__rhs.time_since_epoch() + __lhs);
745  }
746 
747  template<typename _Clock, typename _Dur1,
748  typename _Rep2, typename _Period2>
749  constexpr time_point<_Clock,
750  typename common_type<_Dur1, duration<_Rep2, _Period2>>::type>
751  operator-(const time_point<_Clock, _Dur1>& __lhs,
752  const duration<_Rep2, _Period2>& __rhs)
753  {
754  typedef duration<_Rep2, _Period2> __dur2;
755  typedef typename common_type<_Dur1,__dur2>::type __ct;
756  typedef time_point<_Clock, __ct> __time_point;
757  return __time_point(__lhs.time_since_epoch() -__rhs);
758  }
759 
760  template<typename _Clock, typename _Dur1, typename _Dur2>
761  constexpr typename common_type<_Dur1, _Dur2>::type
762  operator-(const time_point<_Clock, _Dur1>& __lhs,
763  const time_point<_Clock, _Dur2>& __rhs)
764  { return __lhs.time_since_epoch() - __rhs.time_since_epoch(); }
765 
766  template<typename _Clock, typename _Dur1, typename _Dur2>
767  constexpr bool
768  operator==(const time_point<_Clock, _Dur1>& __lhs,
769  const time_point<_Clock, _Dur2>& __rhs)
770  { return __lhs.time_since_epoch() == __rhs.time_since_epoch(); }
771 
772  template<typename _Clock, typename _Dur1, typename _Dur2>
773  constexpr bool
774  operator!=(const time_point<_Clock, _Dur1>& __lhs,
775  const time_point<_Clock, _Dur2>& __rhs)
776  { return !(__lhs == __rhs); }
777 
778  template<typename _Clock, typename _Dur1, typename _Dur2>
779  constexpr bool
780  operator<(const time_point<_Clock, _Dur1>& __lhs,
781  const time_point<_Clock, _Dur2>& __rhs)
782  { return __lhs.time_since_epoch() < __rhs.time_since_epoch(); }
783 
784  template<typename _Clock, typename _Dur1, typename _Dur2>
785  constexpr bool
786  operator<=(const time_point<_Clock, _Dur1>& __lhs,
787  const time_point<_Clock, _Dur2>& __rhs)
788  { return !(__rhs < __lhs); }
789 
790  template<typename _Clock, typename _Dur1, typename _Dur2>
791  constexpr bool
792  operator>(const time_point<_Clock, _Dur1>& __lhs,
793  const time_point<_Clock, _Dur2>& __rhs)
794  { return __rhs < __lhs; }
795 
796  template<typename _Clock, typename _Dur1, typename _Dur2>
797  constexpr bool
798  operator>=(const time_point<_Clock, _Dur1>& __lhs,
799  const time_point<_Clock, _Dur2>& __rhs)
800  { return !(__lhs < __rhs); }
801 
802 
803  // Clocks.
804 
805  // Why nanosecond resolution as the default?
806  // Why have std::system_clock always count in the highest
807  // resolution (ie nanoseconds), even if on some OSes the low 3
808  // or 9 decimal digits will be always zero? This allows later
809  // implementations to change the system_clock::now()
810  // implementation any time to provide better resolution without
811  // changing function signature or units.
812 
813  // To support the (forward) evolution of the library's defined
814  // clocks, wrap inside inline namespace so that the current
815  // defintions of system_clock, steady_clock, and
816  // high_resolution_clock types are uniquely mangled. This way, new
817  // code can use the latests clocks, while the library can contain
818  // compatibility definitions for previous versions. At some
819  // point, when these clocks settle down, the inlined namespaces
820  // can be removed. XXX GLIBCXX_ABI Deprecated
821  inline namespace _V2 {
822 
823  /**
824  * @brief System clock.
825  *
826  * Time returned represents wall time from the system-wide clock.
827  */
828  struct system_clock
829  {
830  typedef chrono::nanoseconds duration;
831  typedef duration::rep rep;
832  typedef duration::period period;
833  typedef chrono::time_point<system_clock, duration> time_point;
834 
835  static_assert(system_clock::duration::min()
836  < system_clock::duration::zero(),
837  "a clock's minimum duration cannot be less than its epoch");
838 
839  static constexpr bool is_steady = false;
840 
841  static time_point
842  now() noexcept;
843 
844  // Map to C API
845  static std::time_t
846  to_time_t(const time_point& __t) noexcept
847  {
848  return std::time_t(duration_cast<chrono::seconds>
849  (__t.time_since_epoch()).count());
850  }
851 
852  static time_point
853  from_time_t(std::time_t __t) noexcept
854  {
855  typedef chrono::time_point<system_clock, seconds> __from;
856  return time_point_cast<system_clock::duration>
857  (__from(chrono::seconds(__t)));
858  }
859  };
860 
861 
862  /**
863  * @brief Monotonic clock
864  *
865  * Time returned has the property of only increasing at a uniform rate.
866  */
867  struct steady_clock
868  {
869  typedef chrono::nanoseconds duration;
870  typedef duration::rep rep;
871  typedef duration::period period;
872  typedef chrono::time_point<steady_clock, duration> time_point;
873 
874  static constexpr bool is_steady = true;
875 
876  static time_point
877  now() noexcept;
878  };
879 
880 
881  /**
882  * @brief Highest-resolution clock
883  *
884  * This is the clock "with the shortest tick period." Alias to
885  * std::system_clock until higher-than-nanosecond definitions
886  * become feasible.
887  */
888  using high_resolution_clock = system_clock;
889 
890  } // end inline namespace _V2
891  } // namespace chrono
892 
893 #if __cplusplus > 201103L
894 
895 #define __cpp_lib_chrono_udls 201304
896 
897  inline namespace literals
898  {
899  inline namespace chrono_literals
900  {
901 #pragma GCC diagnostic push
902 #pragma GCC diagnostic ignored "-Wliteral-suffix"
903  template<typename _Dur, char... _Digits>
904  constexpr _Dur __check_overflow()
905  {
906  using _Val = __parse_int::_Parse_int<_Digits...>;
907  constexpr typename _Dur::rep __repval = _Val::value;
908  static_assert(__repval >= 0 && __repval == _Val::value,
909  "literal value cannot be represented by duration type");
910  return _Dur(__repval);
911  }
912 
913  constexpr chrono::duration<long double, ratio<3600,1>>
914  operator""h(long double __hours)
915  { return chrono::duration<long double, ratio<3600,1>>{__hours}; }
916 
917  template <char... _Digits>
918  constexpr chrono::hours
919  operator""h()
920  { return __check_overflow<chrono::hours, _Digits...>(); }
921 
922  constexpr chrono::duration<long double, ratio<60,1>>
923  operator""min(long double __mins)
924  { return chrono::duration<long double, ratio<60,1>>{__mins}; }
925 
926  template <char... _Digits>
927  constexpr chrono::minutes
928  operator""min()
929  { return __check_overflow<chrono::minutes, _Digits...>(); }
930 
931  constexpr chrono::duration<long double>
932  operator""s(long double __secs)
933  { return chrono::duration<long double>{__secs}; }
934 
935  template <char... _Digits>
936  constexpr chrono::seconds
937  operator""s()
938  { return __check_overflow<chrono::seconds, _Digits...>(); }
939 
940  constexpr chrono::duration<long double, milli>
941  operator""ms(long double __msecs)
942  { return chrono::duration<long double, milli>{__msecs}; }
943 
944  template <char... _Digits>
945  constexpr chrono::milliseconds
946  operator""ms()
947  { return __check_overflow<chrono::milliseconds, _Digits...>(); }
948 
949  constexpr chrono::duration<long double, micro>
950  operator""us(long double __usecs)
951  { return chrono::duration<long double, micro>{__usecs}; }
952 
953  template <char... _Digits>
954  constexpr chrono::microseconds
955  operator""us()
956  { return __check_overflow<chrono::microseconds, _Digits...>(); }
957 
958  constexpr chrono::duration<long double, nano>
959  operator""ns(long double __nsecs)
960  { return chrono::duration<long double, nano>{__nsecs}; }
961 
962  template <char... _Digits>
963  constexpr chrono::nanoseconds
964  operator""ns()
965  { return __check_overflow<chrono::nanoseconds, _Digits...>(); }
966 
967 #pragma GCC diagnostic pop
968  } // inline namespace chrono_literals
969  } // inline namespace literals
970 
971  namespace chrono
972  {
973  using namespace literals::chrono_literals;
974  } // namespace chrono
975 
976 #endif // C++14
977 
978  // @} group chrono
979 
980 _GLIBCXX_END_NAMESPACE_VERSION
981 } // namespace std
982 
983 #endif // C++11
984 
985 #endif //_GLIBCXX_CHRONO