libstdc++
chrono
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1 // <chrono> -*- C++ -*-
2 
3 // Copyright (C) 2008-2018 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 #ifdef _GLIBCXX_USE_C99_STDINT_TR1
45 
46 namespace std _GLIBCXX_VISIBILITY(default)
47 {
48 _GLIBCXX_BEGIN_NAMESPACE_VERSION
49 
50  /**
51  * @defgroup chrono Time
52  * @ingroup utilities
53  *
54  * Classes and functions for time.
55  * @{
56  */
57 
58  /** @namespace std::chrono
59  * @brief ISO C++ 2011 entities sub-namespace for time and date.
60  */
61  namespace chrono
62  {
63  template<typename _Rep, typename _Period = ratio<1>>
64  struct duration;
65 
66  template<typename _Clock, typename _Dur = typename _Clock::duration>
67  struct time_point;
68  }
69 
70  // 20.11.4.3 specialization of common_type (for duration, sfinae-friendly)
71 
72  template<typename _CT, typename _Period1, typename _Period2>
73  struct __duration_common_type_wrapper
74  {
75  private:
76  typedef __static_gcd<_Period1::num, _Period2::num> __gcd_num;
77  typedef __static_gcd<_Period1::den, _Period2::den> __gcd_den;
78  typedef typename _CT::type __cr;
79  typedef ratio<__gcd_num::value,
80  (_Period1::den / __gcd_den::value) * _Period2::den> __r;
81  public:
82  typedef __success_type<chrono::duration<__cr, __r>> type;
83  };
84 
85  template<typename _Period1, typename _Period2>
86  struct __duration_common_type_wrapper<__failure_type, _Period1, _Period2>
87  { typedef __failure_type type; };
88 
89  template<typename _Rep1, typename _Period1, typename _Rep2, typename _Period2>
90  struct common_type<chrono::duration<_Rep1, _Period1>,
91  chrono::duration<_Rep2, _Period2>>
92  : public __duration_common_type_wrapper<typename __member_type_wrapper<
93  common_type<_Rep1, _Rep2>>::type, _Period1, _Period2>::type
94  { };
95 
96  // 20.11.4.3 specialization of common_type (for time_point, sfinae-friendly)
97 
98  template<typename _CT, typename _Clock>
99  struct __timepoint_common_type_wrapper
100  {
101  typedef __success_type<chrono::time_point<_Clock, typename _CT::type>>
102  type;
103  };
104 
105  template<typename _Clock>
106  struct __timepoint_common_type_wrapper<__failure_type, _Clock>
107  { typedef __failure_type type; };
108 
109  template<typename _Clock, typename _Duration1, typename _Duration2>
110  struct common_type<chrono::time_point<_Clock, _Duration1>,
111  chrono::time_point<_Clock, _Duration2>>
112  : public __timepoint_common_type_wrapper<typename __member_type_wrapper<
113  common_type<_Duration1, _Duration2>>::type, _Clock>::type
114  { };
115 
116  namespace chrono
117  {
118  // Primary template for duration_cast impl.
119  template<typename _ToDur, typename _CF, typename _CR,
120  bool _NumIsOne = false, bool _DenIsOne = false>
121  struct __duration_cast_impl
122  {
123  template<typename _Rep, typename _Period>
124  static constexpr _ToDur
125  __cast(const duration<_Rep, _Period>& __d)
126  {
127  typedef typename _ToDur::rep __to_rep;
128  return _ToDur(static_cast<__to_rep>(static_cast<_CR>(__d.count())
129  * static_cast<_CR>(_CF::num)
130  / static_cast<_CR>(_CF::den)));
131  }
132  };
133 
134  template<typename _ToDur, typename _CF, typename _CR>
135  struct __duration_cast_impl<_ToDur, _CF, _CR, true, true>
136  {
137  template<typename _Rep, typename _Period>
138  static constexpr _ToDur
139  __cast(const duration<_Rep, _Period>& __d)
140  {
141  typedef typename _ToDur::rep __to_rep;
142  return _ToDur(static_cast<__to_rep>(__d.count()));
143  }
144  };
145 
146  template<typename _ToDur, typename _CF, typename _CR>
147  struct __duration_cast_impl<_ToDur, _CF, _CR, true, false>
148  {
149  template<typename _Rep, typename _Period>
150  static constexpr _ToDur
151  __cast(const duration<_Rep, _Period>& __d)
152  {
153  typedef typename _ToDur::rep __to_rep;
154  return _ToDur(static_cast<__to_rep>(
155  static_cast<_CR>(__d.count()) / static_cast<_CR>(_CF::den)));
156  }
157  };
158 
159  template<typename _ToDur, typename _CF, typename _CR>
160  struct __duration_cast_impl<_ToDur, _CF, _CR, false, true>
161  {
162  template<typename _Rep, typename _Period>
163  static constexpr _ToDur
164  __cast(const duration<_Rep, _Period>& __d)
165  {
166  typedef typename _ToDur::rep __to_rep;
167  return _ToDur(static_cast<__to_rep>(
168  static_cast<_CR>(__d.count()) * static_cast<_CR>(_CF::num)));
169  }
170  };
171 
172  template<typename _Tp>
173  struct __is_duration
174  : std::false_type
175  { };
176 
177  template<typename _Rep, typename _Period>
178  struct __is_duration<duration<_Rep, _Period>>
179  : std::true_type
180  { };
181 
182  template<typename _Tp>
183  using __enable_if_is_duration
184  = typename enable_if<__is_duration<_Tp>::value, _Tp>::type;
185 
186  template<typename _Tp>
187  using __disable_if_is_duration
188  = typename enable_if<!__is_duration<_Tp>::value, _Tp>::type;
189 
190  /// duration_cast
191  template<typename _ToDur, typename _Rep, typename _Period>
192  constexpr __enable_if_is_duration<_ToDur>
193  duration_cast(const duration<_Rep, _Period>& __d)
194  {
195  typedef typename _ToDur::period __to_period;
196  typedef typename _ToDur::rep __to_rep;
197  typedef ratio_divide<_Period, __to_period> __cf;
198  typedef typename common_type<__to_rep, _Rep, intmax_t>::type
199  __cr;
200  typedef __duration_cast_impl<_ToDur, __cf, __cr,
201  __cf::num == 1, __cf::den == 1> __dc;
202  return __dc::__cast(__d);
203  }
204 
205  /// treat_as_floating_point
206  template<typename _Rep>
207  struct treat_as_floating_point
208  : is_floating_point<_Rep>
209  { };
210 
211 #if __cplusplus > 201402L
212  template <typename _Rep>
213  inline constexpr bool treat_as_floating_point_v =
214  treat_as_floating_point<_Rep>::value;
215 #endif // C++17
216 
217 #if __cplusplus >= 201703L
218 # define __cpp_lib_chrono 201611
219 
220  template<typename _ToDur, typename _Rep, typename _Period>
221  constexpr __enable_if_is_duration<_ToDur>
222  floor(const duration<_Rep, _Period>& __d)
223  {
224  auto __to = chrono::duration_cast<_ToDur>(__d);
225  if (__to > __d)
226  return __to - _ToDur{1};
227  return __to;
228  }
229 
230  template<typename _ToDur, typename _Rep, typename _Period>
231  constexpr __enable_if_is_duration<_ToDur>
232  ceil(const duration<_Rep, _Period>& __d)
233  {
234  auto __to = chrono::duration_cast<_ToDur>(__d);
235  if (__to < __d)
236  return __to + _ToDur{1};
237  return __to;
238  }
239 
240  template <typename _ToDur, typename _Rep, typename _Period>
241  constexpr enable_if_t<
242  __and_<__is_duration<_ToDur>,
243  __not_<treat_as_floating_point<typename _ToDur::rep>>>::value,
244  _ToDur>
245  round(const duration<_Rep, _Period>& __d)
246  {
247  _ToDur __t0 = chrono::floor<_ToDur>(__d);
248  _ToDur __t1 = __t0 + _ToDur{1};
249  auto __diff0 = __d - __t0;
250  auto __diff1 = __t1 - __d;
251  if (__diff0 == __diff1)
252  {
253  if (__t0.count() & 1)
254  return __t1;
255  return __t0;
256  }
257  else if (__diff0 < __diff1)
258  return __t0;
259  return __t1;
260  }
261 
262  template<typename _Rep, typename _Period>
263  constexpr
264  enable_if_t<numeric_limits<_Rep>::is_signed, duration<_Rep, _Period>>
265  abs(duration<_Rep, _Period> __d)
266  {
267  if (__d >= __d.zero())
268  return __d;
269  return -__d;
270  }
271 #endif // C++17
272 
273  /// duration_values
274  template<typename _Rep>
275  struct duration_values
276  {
277  static constexpr _Rep
278  zero()
279  { return _Rep(0); }
280 
281  static constexpr _Rep
282  max()
283  { return numeric_limits<_Rep>::max(); }
284 
285  static constexpr _Rep
286  min()
287  { return numeric_limits<_Rep>::lowest(); }
288  };
289 
290  template<typename _Tp>
291  struct __is_ratio
292  : std::false_type
293  { };
294 
295  template<intmax_t _Num, intmax_t _Den>
296  struct __is_ratio<ratio<_Num, _Den>>
297  : std::true_type
298  { };
299 
300  /// duration
301  template<typename _Rep, typename _Period>
302  struct duration
303  {
304  private:
305  template<typename _Rep2>
306  using __is_float = treat_as_floating_point<_Rep2>;
307 
308  // _Period2 is an exact multiple of _Period
309  template<typename _Period2>
310  using __is_harmonic
311  = __bool_constant<ratio_divide<_Period2, _Period>::den == 1>;
312 
313  public:
314 
315  typedef _Rep rep;
316  typedef _Period period;
317 
318  static_assert(!__is_duration<_Rep>::value, "rep cannot be a duration");
319  static_assert(__is_ratio<_Period>::value,
320  "period must be a specialization of ratio");
321  static_assert(_Period::num > 0, "period must be positive");
322 
323  // 20.11.5.1 construction / copy / destroy
324  constexpr duration() = default;
325 
326  duration(const duration&) = default;
327 
328  template<typename _Rep2, typename = _Require<
329  is_convertible<_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()
432  { return duration(duration_values<rep>::zero()); }
433 
434  static constexpr duration
435  min()
436  { return duration(duration_values<rep>::min()); }
437 
438  static constexpr duration
439  max()
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  template<typename _Rep1, typename _Rep2,
475  typename _CRep = typename common_type<_Rep1, _Rep2>::type>
476  using __common_rep_t
477  = typename enable_if<is_convertible<_Rep2, _CRep>::value, _CRep>::type;
478 
479  template<typename _Rep1, typename _Period, typename _Rep2>
480  constexpr duration<__common_rep_t<_Rep1, _Rep2>, _Period>
481  operator*(const duration<_Rep1, _Period>& __d, const _Rep2& __s)
482  {
483  typedef duration<typename common_type<_Rep1, _Rep2>::type, _Period>
484  __cd;
485  return __cd(__cd(__d).count() * __s);
486  }
487 
488  template<typename _Rep1, typename _Rep2, typename _Period>
489  constexpr duration<__common_rep_t<_Rep2, _Rep1>, _Period>
490  operator*(const _Rep1& __s, const duration<_Rep2, _Period>& __d)
491  { return __d * __s; }
492 
493  template<typename _Rep1, typename _Period, typename _Rep2>
494  constexpr
495  duration<__common_rep_t<_Rep1, __disable_if_is_duration<_Rep2>>, _Period>
496  operator/(const duration<_Rep1, _Period>& __d, const _Rep2& __s)
497  {
498  typedef duration<typename common_type<_Rep1, _Rep2>::type, _Period>
499  __cd;
500  return __cd(__cd(__d).count() / __s);
501  }
502 
503  template<typename _Rep1, typename _Period1,
504  typename _Rep2, typename _Period2>
505  constexpr typename common_type<_Rep1, _Rep2>::type
506  operator/(const duration<_Rep1, _Period1>& __lhs,
507  const duration<_Rep2, _Period2>& __rhs)
508  {
509  typedef duration<_Rep1, _Period1> __dur1;
510  typedef duration<_Rep2, _Period2> __dur2;
511  typedef typename common_type<__dur1,__dur2>::type __cd;
512  return __cd(__lhs).count() / __cd(__rhs).count();
513  }
514 
515  // DR 934.
516  template<typename _Rep1, typename _Period, typename _Rep2>
517  constexpr
518  duration<__common_rep_t<_Rep1, __disable_if_is_duration<_Rep2>>, _Period>
519  operator%(const duration<_Rep1, _Period>& __d, const _Rep2& __s)
520  {
521  typedef duration<typename common_type<_Rep1, _Rep2>::type, _Period>
522  __cd;
523  return __cd(__cd(__d).count() % __s);
524  }
525 
526  template<typename _Rep1, typename _Period1,
527  typename _Rep2, typename _Period2>
528  constexpr typename common_type<duration<_Rep1, _Period1>,
529  duration<_Rep2, _Period2>>::type
530  operator%(const duration<_Rep1, _Period1>& __lhs,
531  const duration<_Rep2, _Period2>& __rhs)
532  {
533  typedef duration<_Rep1, _Period1> __dur1;
534  typedef duration<_Rep2, _Period2> __dur2;
535  typedef typename common_type<__dur1,__dur2>::type __cd;
536  return __cd(__cd(__lhs).count() % __cd(__rhs).count());
537  }
538 
539  // comparisons
540  template<typename _Rep1, typename _Period1,
541  typename _Rep2, typename _Period2>
542  constexpr bool
543  operator==(const duration<_Rep1, _Period1>& __lhs,
544  const duration<_Rep2, _Period2>& __rhs)
545  {
546  typedef duration<_Rep1, _Period1> __dur1;
547  typedef duration<_Rep2, _Period2> __dur2;
548  typedef typename common_type<__dur1,__dur2>::type __ct;
549  return __ct(__lhs).count() == __ct(__rhs).count();
550  }
551 
552  template<typename _Rep1, typename _Period1,
553  typename _Rep2, typename _Period2>
554  constexpr bool
555  operator<(const duration<_Rep1, _Period1>& __lhs,
556  const duration<_Rep2, _Period2>& __rhs)
557  {
558  typedef duration<_Rep1, _Period1> __dur1;
559  typedef duration<_Rep2, _Period2> __dur2;
560  typedef typename common_type<__dur1,__dur2>::type __ct;
561  return __ct(__lhs).count() < __ct(__rhs).count();
562  }
563 
564  template<typename _Rep1, typename _Period1,
565  typename _Rep2, typename _Period2>
566  constexpr bool
567  operator!=(const duration<_Rep1, _Period1>& __lhs,
568  const duration<_Rep2, _Period2>& __rhs)
569  { return !(__lhs == __rhs); }
570 
571  template<typename _Rep1, typename _Period1,
572  typename _Rep2, typename _Period2>
573  constexpr bool
574  operator<=(const duration<_Rep1, _Period1>& __lhs,
575  const duration<_Rep2, _Period2>& __rhs)
576  { return !(__rhs < __lhs); }
577 
578  template<typename _Rep1, typename _Period1,
579  typename _Rep2, typename _Period2>
580  constexpr bool
581  operator>(const duration<_Rep1, _Period1>& __lhs,
582  const duration<_Rep2, _Period2>& __rhs)
583  { return __rhs < __lhs; }
584 
585  template<typename _Rep1, typename _Period1,
586  typename _Rep2, typename _Period2>
587  constexpr bool
588  operator>=(const duration<_Rep1, _Period1>& __lhs,
589  const duration<_Rep2, _Period2>& __rhs)
590  { return !(__lhs < __rhs); }
591 
592  /// nanoseconds
593  typedef duration<int64_t, nano> nanoseconds;
594 
595  /// microseconds
596  typedef duration<int64_t, micro> microseconds;
597 
598  /// milliseconds
599  typedef duration<int64_t, milli> milliseconds;
600 
601  /// seconds
602  typedef duration<int64_t> seconds;
603 
604  /// minutes
605  typedef duration<int64_t, ratio< 60>> minutes;
606 
607  /// hours
608  typedef duration<int64_t, ratio<3600>> hours;
609 
610  /// time_point
611  template<typename _Clock, typename _Dur>
612  struct time_point
613  {
614  typedef _Clock clock;
615  typedef _Dur duration;
616  typedef typename duration::rep rep;
617  typedef typename duration::period period;
618 
619  constexpr time_point() : __d(duration::zero())
620  { }
621 
622  constexpr explicit time_point(const duration& __dur)
623  : __d(__dur)
624  { }
625 
626  // conversions
627  template<typename _Dur2,
628  typename = _Require<is_convertible<_Dur2, _Dur>>>
629  constexpr time_point(const time_point<clock, _Dur2>& __t)
630  : __d(__t.time_since_epoch())
631  { }
632 
633  // observer
634  constexpr duration
635  time_since_epoch() const
636  { return __d; }
637 
638  // arithmetic
639  _GLIBCXX17_CONSTEXPR time_point&
640  operator+=(const duration& __dur)
641  {
642  __d += __dur;
643  return *this;
644  }
645 
646  _GLIBCXX17_CONSTEXPR time_point&
647  operator-=(const duration& __dur)
648  {
649  __d -= __dur;
650  return *this;
651  }
652 
653  // special values
654  static constexpr time_point
655  min()
656  { return time_point(duration::min()); }
657 
658  static constexpr time_point
659  max()
660  { return time_point(duration::max()); }
661 
662  private:
663  duration __d;
664  };
665 
666  /// time_point_cast
667  template<typename _ToDur, typename _Clock, typename _Dur>
668  constexpr typename enable_if<__is_duration<_ToDur>::value,
669  time_point<_Clock, _ToDur>>::type
670  time_point_cast(const time_point<_Clock, _Dur>& __t)
671  {
672  typedef time_point<_Clock, _ToDur> __time_point;
673  return __time_point(duration_cast<_ToDur>(__t.time_since_epoch()));
674  }
675 
676 #if __cplusplus > 201402L
677  template<typename _ToDur, typename _Clock, typename _Dur>
678  constexpr
679  enable_if_t<__is_duration<_ToDur>::value, time_point<_Clock, _ToDur>>
680  floor(const time_point<_Clock, _Dur>& __tp)
681  {
682  return time_point<_Clock, _ToDur>{
683  chrono::floor<_ToDur>(__tp.time_since_epoch())};
684  }
685 
686  template<typename _ToDur, typename _Clock, typename _Dur>
687  constexpr
688  enable_if_t<__is_duration<_ToDur>::value, time_point<_Clock, _ToDur>>
689  ceil(const time_point<_Clock, _Dur>& __tp)
690  {
691  return time_point<_Clock, _ToDur>{
692  chrono::ceil<_ToDur>(__tp.time_since_epoch())};
693  }
694 
695  template<typename _ToDur, typename _Clock, typename _Dur>
696  constexpr enable_if_t<
697  __and_<__is_duration<_ToDur>,
698  __not_<treat_as_floating_point<typename _ToDur::rep>>>::value,
699  time_point<_Clock, _ToDur>>
700  round(const time_point<_Clock, _Dur>& __tp)
701  {
702  return time_point<_Clock, _ToDur>{
703  chrono::round<_ToDur>(__tp.time_since_epoch())};
704  }
705 #endif // C++17
706 
707  template<typename _Clock, typename _Dur1,
708  typename _Rep2, typename _Period2>
709  constexpr time_point<_Clock,
710  typename common_type<_Dur1, duration<_Rep2, _Period2>>::type>
711  operator+(const time_point<_Clock, _Dur1>& __lhs,
712  const duration<_Rep2, _Period2>& __rhs)
713  {
714  typedef duration<_Rep2, _Period2> __dur2;
715  typedef typename common_type<_Dur1,__dur2>::type __ct;
716  typedef time_point<_Clock, __ct> __time_point;
717  return __time_point(__lhs.time_since_epoch() + __rhs);
718  }
719 
720  template<typename _Rep1, typename _Period1,
721  typename _Clock, typename _Dur2>
722  constexpr time_point<_Clock,
723  typename common_type<duration<_Rep1, _Period1>, _Dur2>::type>
724  operator+(const duration<_Rep1, _Period1>& __lhs,
725  const time_point<_Clock, _Dur2>& __rhs)
726  {
727  typedef duration<_Rep1, _Period1> __dur1;
728  typedef typename common_type<__dur1,_Dur2>::type __ct;
729  typedef time_point<_Clock, __ct> __time_point;
730  return __time_point(__rhs.time_since_epoch() + __lhs);
731  }
732 
733  template<typename _Clock, typename _Dur1,
734  typename _Rep2, typename _Period2>
735  constexpr time_point<_Clock,
736  typename common_type<_Dur1, duration<_Rep2, _Period2>>::type>
737  operator-(const time_point<_Clock, _Dur1>& __lhs,
738  const duration<_Rep2, _Period2>& __rhs)
739  {
740  typedef duration<_Rep2, _Period2> __dur2;
741  typedef typename common_type<_Dur1,__dur2>::type __ct;
742  typedef time_point<_Clock, __ct> __time_point;
743  return __time_point(__lhs.time_since_epoch() -__rhs);
744  }
745 
746  template<typename _Clock, typename _Dur1, typename _Dur2>
747  constexpr typename common_type<_Dur1, _Dur2>::type
748  operator-(const time_point<_Clock, _Dur1>& __lhs,
749  const time_point<_Clock, _Dur2>& __rhs)
750  { return __lhs.time_since_epoch() - __rhs.time_since_epoch(); }
751 
752  template<typename _Clock, typename _Dur1, typename _Dur2>
753  constexpr bool
754  operator==(const time_point<_Clock, _Dur1>& __lhs,
755  const time_point<_Clock, _Dur2>& __rhs)
756  { return __lhs.time_since_epoch() == __rhs.time_since_epoch(); }
757 
758  template<typename _Clock, typename _Dur1, typename _Dur2>
759  constexpr bool
760  operator!=(const time_point<_Clock, _Dur1>& __lhs,
761  const time_point<_Clock, _Dur2>& __rhs)
762  { return !(__lhs == __rhs); }
763 
764  template<typename _Clock, typename _Dur1, typename _Dur2>
765  constexpr bool
766  operator<(const time_point<_Clock, _Dur1>& __lhs,
767  const time_point<_Clock, _Dur2>& __rhs)
768  { return __lhs.time_since_epoch() < __rhs.time_since_epoch(); }
769 
770  template<typename _Clock, typename _Dur1, typename _Dur2>
771  constexpr bool
772  operator<=(const time_point<_Clock, _Dur1>& __lhs,
773  const time_point<_Clock, _Dur2>& __rhs)
774  { return !(__rhs < __lhs); }
775 
776  template<typename _Clock, typename _Dur1, typename _Dur2>
777  constexpr bool
778  operator>(const time_point<_Clock, _Dur1>& __lhs,
779  const time_point<_Clock, _Dur2>& __rhs)
780  { return __rhs < __lhs; }
781 
782  template<typename _Clock, typename _Dur1, typename _Dur2>
783  constexpr bool
784  operator>=(const time_point<_Clock, _Dur1>& __lhs,
785  const time_point<_Clock, _Dur2>& __rhs)
786  { return !(__lhs < __rhs); }
787 
788 
789  // Clocks.
790 
791  // Why nanosecond resolution as the default?
792  // Why have std::system_clock always count in the highest
793  // resolution (ie nanoseconds), even if on some OSes the low 3
794  // or 9 decimal digits will be always zero? This allows later
795  // implementations to change the system_clock::now()
796  // implementation any time to provide better resolution without
797  // changing function signature or units.
798 
799  // To support the (forward) evolution of the library's defined
800  // clocks, wrap inside inline namespace so that the current
801  // defintions of system_clock, steady_clock, and
802  // high_resolution_clock types are uniquely mangled. This way, new
803  // code can use the latests clocks, while the library can contain
804  // compatibility definitions for previous versions. At some
805  // point, when these clocks settle down, the inlined namespaces
806  // can be removed. XXX GLIBCXX_ABI Deprecated
807  inline namespace _V2 {
808 
809  /**
810  * @brief System clock.
811  *
812  * Time returned represents wall time from the system-wide clock.
813  */
814  struct system_clock
815  {
816  typedef chrono::nanoseconds duration;
817  typedef duration::rep rep;
818  typedef duration::period period;
819  typedef chrono::time_point<system_clock, duration> time_point;
820 
821  static_assert(system_clock::duration::min()
822  < system_clock::duration::zero(),
823  "a clock's minimum duration cannot be less than its epoch");
824 
825  static constexpr bool is_steady = false;
826 
827  static time_point
828  now() noexcept;
829 
830  // Map to C API
831  static std::time_t
832  to_time_t(const time_point& __t) noexcept
833  {
834  return std::time_t(duration_cast<chrono::seconds>
835  (__t.time_since_epoch()).count());
836  }
837 
838  static time_point
839  from_time_t(std::time_t __t) noexcept
840  {
841  typedef chrono::time_point<system_clock, seconds> __from;
842  return time_point_cast<system_clock::duration>
843  (__from(chrono::seconds(__t)));
844  }
845  };
846 
847 
848  /**
849  * @brief Monotonic clock
850  *
851  * Time returned has the property of only increasing at a uniform rate.
852  */
853  struct steady_clock
854  {
855  typedef chrono::nanoseconds duration;
856  typedef duration::rep rep;
857  typedef duration::period period;
858  typedef chrono::time_point<steady_clock, duration> time_point;
859 
860  static constexpr bool is_steady = true;
861 
862  static time_point
863  now() noexcept;
864  };
865 
866 
867  /**
868  * @brief Highest-resolution clock
869  *
870  * This is the clock "with the shortest tick period." Alias to
871  * std::system_clock until higher-than-nanosecond definitions
872  * become feasible.
873  */
874  using high_resolution_clock = system_clock;
875 
876  } // end inline namespace _V2
877  } // namespace chrono
878 
879 #if __cplusplus > 201103L
880 
881 #define __cpp_lib_chrono_udls 201304
882 
883  inline namespace literals
884  {
885  inline namespace chrono_literals
886  {
887 #pragma GCC diagnostic push
888 #pragma GCC diagnostic ignored "-Wliteral-suffix"
889  template<typename _Rep, unsigned long long _Val>
890  struct _Checked_integral_constant
891  : integral_constant<_Rep, static_cast<_Rep>(_Val)>
892  {
893  static_assert(_Checked_integral_constant::value >= 0
894  && _Checked_integral_constant::value == _Val,
895  "literal value cannot be represented by duration type");
896  };
897 
898  template<typename _Dur, char... _Digits>
899  constexpr _Dur __check_overflow()
900  {
901  using _Val = __parse_int::_Parse_int<_Digits...>;
902  using _Rep = typename _Dur::rep;
903  // TODO: should be simply integral_constant<_Rep, _Val::value>
904  // but GCC doesn't reject narrowing conversions to _Rep.
905  using _CheckedVal = _Checked_integral_constant<_Rep, _Val::value>;
906  return _Dur{_CheckedVal::value};
907  }
908 
909  constexpr chrono::duration<long double, ratio<3600,1>>
910  operator""h(long double __hours)
911  { return chrono::duration<long double, ratio<3600,1>>{__hours}; }
912 
913  template <char... _Digits>
914  constexpr chrono::hours
915  operator""h()
916  { return __check_overflow<chrono::hours, _Digits...>(); }
917 
918  constexpr chrono::duration<long double, ratio<60,1>>
919  operator""min(long double __mins)
920  { return chrono::duration<long double, ratio<60,1>>{__mins}; }
921 
922  template <char... _Digits>
923  constexpr chrono::minutes
924  operator""min()
925  { return __check_overflow<chrono::minutes, _Digits...>(); }
926 
927  constexpr chrono::duration<long double>
928  operator""s(long double __secs)
929  { return chrono::duration<long double>{__secs}; }
930 
931  template <char... _Digits>
932  constexpr chrono::seconds
933  operator""s()
934  { return __check_overflow<chrono::seconds, _Digits...>(); }
935 
936  constexpr chrono::duration<long double, milli>
937  operator""ms(long double __msecs)
938  { return chrono::duration<long double, milli>{__msecs}; }
939 
940  template <char... _Digits>
941  constexpr chrono::milliseconds
942  operator""ms()
943  { return __check_overflow<chrono::milliseconds, _Digits...>(); }
944 
945  constexpr chrono::duration<long double, micro>
946  operator""us(long double __usecs)
947  { return chrono::duration<long double, micro>{__usecs}; }
948 
949  template <char... _Digits>
950  constexpr chrono::microseconds
951  operator""us()
952  { return __check_overflow<chrono::microseconds, _Digits...>(); }
953 
954  constexpr chrono::duration<long double, nano>
955  operator""ns(long double __nsecs)
956  { return chrono::duration<long double, nano>{__nsecs}; }
957 
958  template <char... _Digits>
959  constexpr chrono::nanoseconds
960  operator""ns()
961  { return __check_overflow<chrono::nanoseconds, _Digits...>(); }
962 
963 #pragma GCC diagnostic pop
964  } // inline namespace chrono_literals
965  } // inline namespace literals
966 
967  namespace chrono
968  {
969  using namespace literals::chrono_literals;
970  } // namespace chrono
971 
972 #endif // C++14
973 
974  // @} group chrono
975 
976 _GLIBCXX_END_NAMESPACE_VERSION
977 } // namespace std
978 
979 #endif //_GLIBCXX_USE_C99_STDINT_TR1
980 
981 #endif // C++11
982 
983 #endif //_GLIBCXX_CHRONO