libstdc++
chrono
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1 // <chrono> -*- C++ -*-
2 
3 // Copyright (C) 2008-2017 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  /**
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  _GLIBCXX_BEGIN_NAMESPACE_VERSION
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  _GLIBCXX_END_NAMESPACE_VERSION
70  }
71 
72 _GLIBCXX_BEGIN_NAMESPACE_VERSION
73 
74  // 20.11.4.3 specialization of common_type (for duration, sfinae-friendly)
75 
76  template<typename _CT, typename _Period1, typename _Period2>
77  struct __duration_common_type_wrapper
78  {
79  private:
80  typedef __static_gcd<_Period1::num, _Period2::num> __gcd_num;
81  typedef __static_gcd<_Period1::den, _Period2::den> __gcd_den;
82  typedef typename _CT::type __cr;
83  typedef ratio<__gcd_num::value,
84  (_Period1::den / __gcd_den::value) * _Period2::den> __r;
85  public:
86  typedef __success_type<chrono::duration<__cr, __r>> type;
87  };
88 
89  template<typename _Period1, typename _Period2>
90  struct __duration_common_type_wrapper<__failure_type, _Period1, _Period2>
91  { typedef __failure_type type; };
92 
93  template<typename _Rep1, typename _Period1, typename _Rep2, typename _Period2>
94  struct common_type<chrono::duration<_Rep1, _Period1>,
95  chrono::duration<_Rep2, _Period2>>
96  : public __duration_common_type_wrapper<typename __member_type_wrapper<
97  common_type<_Rep1, _Rep2>>::type, _Period1, _Period2>::type
98  { };
99 
100  // 20.11.4.3 specialization of common_type (for time_point, sfinae-friendly)
101 
102  template<typename _CT, typename _Clock>
103  struct __timepoint_common_type_wrapper
104  {
105  typedef __success_type<chrono::time_point<_Clock, typename _CT::type>>
106  type;
107  };
108 
109  template<typename _Clock>
110  struct __timepoint_common_type_wrapper<__failure_type, _Clock>
111  { typedef __failure_type type; };
112 
113  template<typename _Clock, typename _Duration1, typename _Duration2>
114  struct common_type<chrono::time_point<_Clock, _Duration1>,
115  chrono::time_point<_Clock, _Duration2>>
116  : public __timepoint_common_type_wrapper<typename __member_type_wrapper<
117  common_type<_Duration1, _Duration2>>::type, _Clock>::type
118  { };
119 
120 _GLIBCXX_END_NAMESPACE_VERSION
121 
122  namespace chrono
123  {
124  _GLIBCXX_BEGIN_NAMESPACE_VERSION
125 
126  // Primary template for duration_cast impl.
127  template<typename _ToDur, typename _CF, typename _CR,
128  bool _NumIsOne = false, bool _DenIsOne = false>
129  struct __duration_cast_impl
130  {
131  template<typename _Rep, typename _Period>
132  static constexpr _ToDur
133  __cast(const duration<_Rep, _Period>& __d)
134  {
135  typedef typename _ToDur::rep __to_rep;
136  return _ToDur(static_cast<__to_rep>(static_cast<_CR>(__d.count())
137  * static_cast<_CR>(_CF::num)
138  / static_cast<_CR>(_CF::den)));
139  }
140  };
141 
142  template<typename _ToDur, typename _CF, typename _CR>
143  struct __duration_cast_impl<_ToDur, _CF, _CR, true, true>
144  {
145  template<typename _Rep, typename _Period>
146  static constexpr _ToDur
147  __cast(const duration<_Rep, _Period>& __d)
148  {
149  typedef typename _ToDur::rep __to_rep;
150  return _ToDur(static_cast<__to_rep>(__d.count()));
151  }
152  };
153 
154  template<typename _ToDur, typename _CF, typename _CR>
155  struct __duration_cast_impl<_ToDur, _CF, _CR, true, false>
156  {
157  template<typename _Rep, typename _Period>
158  static constexpr _ToDur
159  __cast(const duration<_Rep, _Period>& __d)
160  {
161  typedef typename _ToDur::rep __to_rep;
162  return _ToDur(static_cast<__to_rep>(
163  static_cast<_CR>(__d.count()) / static_cast<_CR>(_CF::den)));
164  }
165  };
166 
167  template<typename _ToDur, typename _CF, typename _CR>
168  struct __duration_cast_impl<_ToDur, _CF, _CR, false, true>
169  {
170  template<typename _Rep, typename _Period>
171  static constexpr _ToDur
172  __cast(const duration<_Rep, _Period>& __d)
173  {
174  typedef typename _ToDur::rep __to_rep;
175  return _ToDur(static_cast<__to_rep>(
176  static_cast<_CR>(__d.count()) * static_cast<_CR>(_CF::num)));
177  }
178  };
179 
180  template<typename _Tp>
181  struct __is_duration
183  { };
184 
185  template<typename _Rep, typename _Period>
186  struct __is_duration<duration<_Rep, _Period>>
188  { };
189 
190  /// duration_cast
191  template<typename _ToDur, typename _Rep, typename _Period>
192  constexpr typename enable_if<__is_duration<_ToDur>::value,
193  _ToDur>::type
195  {
196  typedef typename _ToDur::period __to_period;
197  typedef typename _ToDur::rep __to_rep;
199  typedef typename common_type<__to_rep, _Rep, intmax_t>::type
200  __cr;
201  typedef __duration_cast_impl<_ToDur, __cf, __cr,
202  __cf::num == 1, __cf::den == 1> __dc;
203  return __dc::__cast(__d);
204  }
205 
206  /// treat_as_floating_point
207  template<typename _Rep>
209  : is_floating_point<_Rep>
210  { };
211 
212 #if __cplusplus > 201402L
213  template <typename _Rep>
214  inline constexpr bool treat_as_floating_point_v =
216 #endif // C++17
217 
218 #if __cplusplus > 201402L
219 # define __cpp_lib_chrono 201510
220 
221  template<typename _ToDur, typename _Rep, typename _Period>
222  constexpr enable_if_t<__is_duration<_ToDur>::value, _ToDur>
223  floor(const duration<_Rep, _Period>& __d)
224  {
225  auto __to = chrono::duration_cast<_ToDur>(__d);
226  if (__to > __d)
227  return __to - _ToDur{1};
228  return __to;
229  }
230 
231  template<typename _ToDur, typename _Rep, typename _Period>
232  constexpr enable_if_t<__is_duration<_ToDur>::value, _ToDur>
233  ceil(const duration<_Rep, _Period>& __d)
234  {
235  auto __to = chrono::duration_cast<_ToDur>(__d);
236  if (__to < __d)
237  return __to + _ToDur{1};
238  return __to;
239  }
240 
241  template <typename _ToDur, typename _Rep, typename _Period>
242  constexpr enable_if_t<
243  __and_<__is_duration<_ToDur>,
244  __not_<treat_as_floating_point<typename _ToDur::rep>>>::value,
245  _ToDur>
246  round(const duration<_Rep, _Period>& __d)
247  {
248  _ToDur __t0 = chrono::floor<_ToDur>(__d);
249  _ToDur __t1 = __t0 + _ToDur{1};
250  auto __diff0 = __d - __t0;
251  auto __diff1 = __t1 - __d;
252  if (__diff0 == __diff1)
253  {
254  if (__t0.count() & 1)
255  return __t1;
256  return __t0;
257  }
258  else if (__diff0 < __diff1)
259  return __t0;
260  return __t1;
261  }
262 
263  template<typename _Rep, typename _Period>
264  constexpr
265  enable_if_t<numeric_limits<_Rep>::is_signed, duration<_Rep, _Period>>
267  {
268  if (__d >= __d.zero())
269  return __d;
270  return -__d;
271  }
272 #endif // C++17
273 
274  /// duration_values
275  template<typename _Rep>
277  {
278  static constexpr _Rep
279  zero()
280  { return _Rep(0); }
281 
282  static constexpr _Rep
283  max()
284  { return numeric_limits<_Rep>::max(); }
285 
286  static constexpr _Rep
287  min()
288  { return numeric_limits<_Rep>::lowest(); }
289  };
290 
291  template<typename _Tp>
292  struct __is_ratio
294  { };
295 
296  template<intmax_t _Num, intmax_t _Den>
297  struct __is_ratio<ratio<_Num, _Den>>
299  { };
300 
301  /// duration
302  template<typename _Rep, typename _Period>
303  struct duration
304  {
305  typedef _Rep rep;
306  typedef _Period period;
307 
308  static_assert(!__is_duration<_Rep>::value, "rep cannot be a duration");
309  static_assert(__is_ratio<_Period>::value,
310  "period must be a specialization of ratio");
311  static_assert(_Period::num > 0, "period must be positive");
312 
313  // 20.11.5.1 construction / copy / destroy
314  constexpr duration() = default;
315 
316  // NB: Make constexpr implicit. This cannot be explicitly
317  // constexpr, as any UDT that is not a literal type with a
318  // constexpr copy constructor will be ill-formed.
319  duration(const duration&) = default;
320 
321  template<typename _Rep2, typename = typename
322  enable_if<is_convertible<_Rep2, rep>::value
325  constexpr explicit duration(const _Rep2& __rep)
326  : __r(static_cast<rep>(__rep)) { }
327 
328  template<typename _Rep2, typename _Period2, typename = typename
329  enable_if<treat_as_floating_point<rep>::value
332  constexpr duration(const duration<_Rep2, _Period2>& __d)
333  : __r(duration_cast<duration>(__d).count()) { }
334 
335  ~duration() = default;
336  duration& operator=(const duration&) = default;
337 
338  // 20.11.5.2 observer
339  constexpr rep
340  count() const
341  { return __r; }
342 
343  // 20.11.5.3 arithmetic
344  constexpr duration
345  operator+() const
346  { return *this; }
347 
348  constexpr duration
349  operator-() const
350  { return duration(-__r); }
351 
352  _GLIBCXX17_CONSTEXPR duration&
353  operator++()
354  {
355  ++__r;
356  return *this;
357  }
358 
359  _GLIBCXX17_CONSTEXPR duration
360  operator++(int)
361  { return duration(__r++); }
362 
363  _GLIBCXX17_CONSTEXPR duration&
364  operator--()
365  {
366  --__r;
367  return *this;
368  }
369 
370  _GLIBCXX17_CONSTEXPR duration
371  operator--(int)
372  { return duration(__r--); }
373 
374  _GLIBCXX17_CONSTEXPR duration&
375  operator+=(const duration& __d)
376  {
377  __r += __d.count();
378  return *this;
379  }
380 
381  _GLIBCXX17_CONSTEXPR duration&
382  operator-=(const duration& __d)
383  {
384  __r -= __d.count();
385  return *this;
386  }
387 
388  _GLIBCXX17_CONSTEXPR duration&
389  operator*=(const rep& __rhs)
390  {
391  __r *= __rhs;
392  return *this;
393  }
394 
395  _GLIBCXX17_CONSTEXPR duration&
396  operator/=(const rep& __rhs)
397  {
398  __r /= __rhs;
399  return *this;
400  }
401 
402  // DR 934.
403  template<typename _Rep2 = rep>
404  _GLIBCXX17_CONSTEXPR
405  typename enable_if<!treat_as_floating_point<_Rep2>::value,
406  duration&>::type
407  operator%=(const rep& __rhs)
408  {
409  __r %= __rhs;
410  return *this;
411  }
412 
413  template<typename _Rep2 = rep>
414  _GLIBCXX17_CONSTEXPR
415  typename enable_if<!treat_as_floating_point<_Rep2>::value,
416  duration&>::type
417  operator%=(const duration& __d)
418  {
419  __r %= __d.count();
420  return *this;
421  }
422 
423  // 20.11.5.4 special values
424  static constexpr duration
425  zero()
426  { return duration(duration_values<rep>::zero()); }
427 
428  static constexpr duration
429  min()
430  { return duration(duration_values<rep>::min()); }
431 
432  static constexpr duration
433  max()
434  { return duration(duration_values<rep>::max()); }
435 
436  private:
437  rep __r;
438  };
439 
440  template<typename _Rep1, typename _Period1,
441  typename _Rep2, typename _Period2>
442  constexpr typename common_type<duration<_Rep1, _Period1>,
444  operator+(const duration<_Rep1, _Period1>& __lhs,
445  const duration<_Rep2, _Period2>& __rhs)
446  {
447  typedef duration<_Rep1, _Period1> __dur1;
448  typedef duration<_Rep2, _Period2> __dur2;
449  typedef typename common_type<__dur1,__dur2>::type __cd;
450  return __cd(__cd(__lhs).count() + __cd(__rhs).count());
451  }
452 
453  template<typename _Rep1, typename _Period1,
454  typename _Rep2, typename _Period2>
455  constexpr typename common_type<duration<_Rep1, _Period1>,
457  operator-(const duration<_Rep1, _Period1>& __lhs,
458  const duration<_Rep2, _Period2>& __rhs)
459  {
460  typedef duration<_Rep1, _Period1> __dur1;
461  typedef duration<_Rep2, _Period2> __dur2;
462  typedef typename common_type<__dur1,__dur2>::type __cd;
463  return __cd(__cd(__lhs).count() - __cd(__rhs).count());
464  }
465 
466  template<typename _Rep1, typename _Rep2, bool =
467  is_convertible<_Rep2,
468  typename common_type<_Rep1, _Rep2>::type>::value>
469  struct __common_rep_type { };
470 
471  template<typename _Rep1, typename _Rep2>
472  struct __common_rep_type<_Rep1, _Rep2, true>
473  { typedef typename common_type<_Rep1, _Rep2>::type type; };
474 
475  template<typename _Rep1, typename _Period, typename _Rep2>
476  constexpr
478  operator*(const duration<_Rep1, _Period>& __d, const _Rep2& __s)
479  {
481  __cd;
482  return __cd(__cd(__d).count() * __s);
483  }
484 
485  template<typename _Rep1, typename _Rep2, typename _Period>
486  constexpr
488  operator*(const _Rep1& __s, const duration<_Rep2, _Period>& __d)
489  { return __d * __s; }
490 
491  template<typename _Rep1, typename _Period, typename _Rep2>
492  constexpr duration<typename __common_rep_type<_Rep1, typename
493  enable_if<!__is_duration<_Rep2>::value, _Rep2>::type>::type, _Period>
494  operator/(const duration<_Rep1, _Period>& __d, const _Rep2& __s)
495  {
497  __cd;
498  return __cd(__cd(__d).count() / __s);
499  }
500 
501  template<typename _Rep1, typename _Period1,
502  typename _Rep2, typename _Period2>
503  constexpr typename common_type<_Rep1, _Rep2>::type
504  operator/(const duration<_Rep1, _Period1>& __lhs,
505  const duration<_Rep2, _Period2>& __rhs)
506  {
507  typedef duration<_Rep1, _Period1> __dur1;
508  typedef duration<_Rep2, _Period2> __dur2;
509  typedef typename common_type<__dur1,__dur2>::type __cd;
510  return __cd(__lhs).count() / __cd(__rhs).count();
511  }
512 
513  // DR 934.
514  template<typename _Rep1, typename _Period, typename _Rep2>
515  constexpr duration<typename __common_rep_type<_Rep1, typename
516  enable_if<!__is_duration<_Rep2>::value, _Rep2>::type>::type, _Period>
517  operator%(const duration<_Rep1, _Period>& __d, const _Rep2& __s)
518  {
520  __cd;
521  return __cd(__cd(__d).count() % __s);
522  }
523 
524  template<typename _Rep1, typename _Period1,
525  typename _Rep2, typename _Period2>
526  constexpr typename common_type<duration<_Rep1, _Period1>,
528  operator%(const duration<_Rep1, _Period1>& __lhs,
529  const duration<_Rep2, _Period2>& __rhs)
530  {
531  typedef duration<_Rep1, _Period1> __dur1;
532  typedef duration<_Rep2, _Period2> __dur2;
533  typedef typename common_type<__dur1,__dur2>::type __cd;
534  return __cd(__cd(__lhs).count() % __cd(__rhs).count());
535  }
536 
537  // comparisons
538  template<typename _Rep1, typename _Period1,
539  typename _Rep2, typename _Period2>
540  constexpr bool
541  operator==(const duration<_Rep1, _Period1>& __lhs,
542  const duration<_Rep2, _Period2>& __rhs)
543  {
544  typedef duration<_Rep1, _Period1> __dur1;
545  typedef duration<_Rep2, _Period2> __dur2;
546  typedef typename common_type<__dur1,__dur2>::type __ct;
547  return __ct(__lhs).count() == __ct(__rhs).count();
548  }
549 
550  template<typename _Rep1, typename _Period1,
551  typename _Rep2, typename _Period2>
552  constexpr bool
553  operator<(const duration<_Rep1, _Period1>& __lhs,
554  const duration<_Rep2, _Period2>& __rhs)
555  {
556  typedef duration<_Rep1, _Period1> __dur1;
557  typedef duration<_Rep2, _Period2> __dur2;
558  typedef typename common_type<__dur1,__dur2>::type __ct;
559  return __ct(__lhs).count() < __ct(__rhs).count();
560  }
561 
562  template<typename _Rep1, typename _Period1,
563  typename _Rep2, typename _Period2>
564  constexpr bool
565  operator!=(const duration<_Rep1, _Period1>& __lhs,
566  const duration<_Rep2, _Period2>& __rhs)
567  { return !(__lhs == __rhs); }
568 
569  template<typename _Rep1, typename _Period1,
570  typename _Rep2, typename _Period2>
571  constexpr bool
572  operator<=(const duration<_Rep1, _Period1>& __lhs,
573  const duration<_Rep2, _Period2>& __rhs)
574  { return !(__rhs < __lhs); }
575 
576  template<typename _Rep1, typename _Period1,
577  typename _Rep2, typename _Period2>
578  constexpr bool
579  operator>(const duration<_Rep1, _Period1>& __lhs,
580  const duration<_Rep2, _Period2>& __rhs)
581  { return __rhs < __lhs; }
582 
583  template<typename _Rep1, typename _Period1,
584  typename _Rep2, typename _Period2>
585  constexpr bool
586  operator>=(const duration<_Rep1, _Period1>& __lhs,
587  const duration<_Rep2, _Period2>& __rhs)
588  { return !(__lhs < __rhs); }
589 
590  /// nanoseconds
592 
593  /// microseconds
595 
596  /// milliseconds
598 
599  /// seconds
601 
602  /// minutes
604 
605  /// hours
607 
608  /// time_point
609  template<typename _Clock, typename _Dur>
610  struct time_point
611  {
612  typedef _Clock clock;
613  typedef _Dur duration;
614  typedef typename duration::rep rep;
615  typedef typename duration::period period;
616 
617  constexpr time_point() : __d(duration::zero())
618  { }
619 
620  constexpr explicit time_point(const duration& __dur)
621  : __d(__dur)
622  { }
623 
624  // conversions
625  template<typename _Dur2>
626  constexpr time_point(const time_point<clock, _Dur2>& __t)
627  : __d(__t.time_since_epoch())
628  { }
629 
630  // observer
631  constexpr duration
632  time_since_epoch() const
633  { return __d; }
634 
635  // arithmetic
636  _GLIBCXX17_CONSTEXPR time_point&
637  operator+=(const duration& __dur)
638  {
639  __d += __dur;
640  return *this;
641  }
642 
643  _GLIBCXX17_CONSTEXPR time_point&
644  operator-=(const duration& __dur)
645  {
646  __d -= __dur;
647  return *this;
648  }
649 
650  // special values
651  static constexpr time_point
652  min()
653  { return time_point(duration::min()); }
654 
655  static constexpr time_point
656  max()
657  { return time_point(duration::max()); }
658 
659  private:
660  duration __d;
661  };
662 
663  /// time_point_cast
664  template<typename _ToDur, typename _Clock, typename _Dur>
665  constexpr typename enable_if<__is_duration<_ToDur>::value,
668  {
669  typedef time_point<_Clock, _ToDur> __time_point;
670  return __time_point(duration_cast<_ToDur>(__t.time_since_epoch()));
671  }
672 
673 #if __cplusplus > 201402L
674  template<typename _ToDur, typename _Clock, typename _Dur>
675  constexpr
676  enable_if_t<__is_duration<_ToDur>::value, time_point<_Clock, _ToDur>>
677  floor(const time_point<_Clock, _Dur>& __tp)
678  {
680  chrono::floor<_ToDur>(__tp.time_since_epoch())};
681  }
682 
683  template<typename _ToDur, typename _Clock, typename _Dur>
684  constexpr
685  enable_if_t<__is_duration<_ToDur>::value, time_point<_Clock, _ToDur>>
686  ceil(const time_point<_Clock, _Dur>& __tp)
687  {
689  chrono::ceil<_ToDur>(__tp.time_since_epoch())};
690  }
691 
692  template<typename _ToDur, typename _Clock, typename _Dur>
693  constexpr enable_if_t<
694  __and_<__is_duration<_ToDur>,
695  __not_<treat_as_floating_point<typename _ToDur::rep>>>::value,
697  round(const time_point<_Clock, _Dur>& __tp)
698  {
700  chrono::round<_ToDur>(__tp.time_since_epoch())};
701  }
702 #endif // C++17
703 
704  template<typename _Clock, typename _Dur1,
705  typename _Rep2, typename _Period2>
706  constexpr time_point<_Clock,
707  typename common_type<_Dur1, duration<_Rep2, _Period2>>::type>
708  operator+(const time_point<_Clock, _Dur1>& __lhs,
709  const duration<_Rep2, _Period2>& __rhs)
710  {
711  typedef duration<_Rep2, _Period2> __dur2;
712  typedef typename common_type<_Dur1,__dur2>::type __ct;
713  typedef time_point<_Clock, __ct> __time_point;
714  return __time_point(__lhs.time_since_epoch() + __rhs);
715  }
716 
717  template<typename _Rep1, typename _Period1,
718  typename _Clock, typename _Dur2>
719  constexpr time_point<_Clock,
720  typename common_type<duration<_Rep1, _Period1>, _Dur2>::type>
721  operator+(const duration<_Rep1, _Period1>& __lhs,
722  const time_point<_Clock, _Dur2>& __rhs)
723  {
724  typedef duration<_Rep1, _Period1> __dur1;
725  typedef typename common_type<__dur1,_Dur2>::type __ct;
726  typedef time_point<_Clock, __ct> __time_point;
727  return __time_point(__rhs.time_since_epoch() + __lhs);
728  }
729 
730  template<typename _Clock, typename _Dur1,
731  typename _Rep2, typename _Period2>
732  constexpr time_point<_Clock,
733  typename common_type<_Dur1, duration<_Rep2, _Period2>>::type>
734  operator-(const time_point<_Clock, _Dur1>& __lhs,
735  const duration<_Rep2, _Period2>& __rhs)
736  {
737  typedef duration<_Rep2, _Period2> __dur2;
738  typedef typename common_type<_Dur1,__dur2>::type __ct;
739  typedef time_point<_Clock, __ct> __time_point;
740  return __time_point(__lhs.time_since_epoch() -__rhs);
741  }
742 
743  template<typename _Clock, typename _Dur1, typename _Dur2>
744  constexpr typename common_type<_Dur1, _Dur2>::type
745  operator-(const time_point<_Clock, _Dur1>& __lhs,
746  const time_point<_Clock, _Dur2>& __rhs)
747  { return __lhs.time_since_epoch() - __rhs.time_since_epoch(); }
748 
749  template<typename _Clock, typename _Dur1, typename _Dur2>
750  constexpr bool
751  operator==(const time_point<_Clock, _Dur1>& __lhs,
752  const time_point<_Clock, _Dur2>& __rhs)
753  { return __lhs.time_since_epoch() == __rhs.time_since_epoch(); }
754 
755  template<typename _Clock, typename _Dur1, typename _Dur2>
756  constexpr bool
757  operator!=(const time_point<_Clock, _Dur1>& __lhs,
758  const time_point<_Clock, _Dur2>& __rhs)
759  { return !(__lhs == __rhs); }
760 
761  template<typename _Clock, typename _Dur1, typename _Dur2>
762  constexpr bool
763  operator<(const time_point<_Clock, _Dur1>& __lhs,
764  const time_point<_Clock, _Dur2>& __rhs)
765  { return __lhs.time_since_epoch() < __rhs.time_since_epoch(); }
766 
767  template<typename _Clock, typename _Dur1, typename _Dur2>
768  constexpr bool
769  operator<=(const time_point<_Clock, _Dur1>& __lhs,
770  const time_point<_Clock, _Dur2>& __rhs)
771  { return !(__rhs < __lhs); }
772 
773  template<typename _Clock, typename _Dur1, typename _Dur2>
774  constexpr bool
775  operator>(const time_point<_Clock, _Dur1>& __lhs,
776  const time_point<_Clock, _Dur2>& __rhs)
777  { return __rhs < __lhs; }
778 
779  template<typename _Clock, typename _Dur1, typename _Dur2>
780  constexpr bool
781  operator>=(const time_point<_Clock, _Dur1>& __lhs,
782  const time_point<_Clock, _Dur2>& __rhs)
783  { return !(__lhs < __rhs); }
784 
785 
786  // Clocks.
787 
788  // Why nanosecond resolution as the default?
789  // Why have std::system_clock always count in the highest
790  // resolution (ie nanoseconds), even if on some OSes the low 3
791  // or 9 decimal digits will be always zero? This allows later
792  // implementations to change the system_clock::now()
793  // implementation any time to provide better resolution without
794  // changing function signature or units.
795 
796  // To support the (forward) evolution of the library's defined
797  // clocks, wrap inside inline namespace so that the current
798  // defintions of system_clock, steady_clock, and
799  // high_resolution_clock types are uniquely mangled. This way, new
800  // code can use the latests clocks, while the library can contain
801  // compatibility definitions for previous versions. At some
802  // point, when these clocks settle down, the inlined namespaces
803  // can be removed. XXX GLIBCXX_ABI Deprecated
804  inline namespace _V2 {
805 
806  /**
807  * @brief System clock.
808  *
809  * Time returned represents wall time from the system-wide clock.
810  */
812  {
814  typedef duration::rep rep;
815  typedef duration::period period;
817 
818  static_assert(system_clock::duration::min()
819  < system_clock::duration::zero(),
820  "a clock's minimum duration cannot be less than its epoch");
821 
822  static constexpr bool is_steady = false;
823 
824  static time_point
825  now() noexcept;
826 
827  // Map to C API
828  static std::time_t
829  to_time_t(const time_point& __t) noexcept
830  {
831  return std::time_t(duration_cast<chrono::seconds>
832  (__t.time_since_epoch()).count());
833  }
834 
835  static time_point
836  from_time_t(std::time_t __t) noexcept
837  {
840  (__from(chrono::seconds(__t)));
841  }
842  };
843 
844 
845  /**
846  * @brief Monotonic clock
847  *
848  * Time returned has the property of only increasing at a uniform rate.
849  */
851  {
853  typedef duration::rep rep;
854  typedef duration::period period;
856 
857  static constexpr bool is_steady = true;
858 
859  static time_point
860  now() noexcept;
861  };
862 
863 
864  /**
865  * @brief Highest-resolution clock
866  *
867  * This is the clock "with the shortest tick period." Alias to
868  * std::system_clock until higher-than-nanosecond definitions
869  * become feasible.
870  */
872 
873  } // end inline namespace _V2
874 
875  _GLIBCXX_END_NAMESPACE_VERSION
876  } // namespace chrono
877 
878 #if __cplusplus > 201103L
879 
880 #define __cpp_lib_chrono_udls 201304
881 
882  inline namespace literals
883  {
884  inline namespace chrono_literals
885  {
886  _GLIBCXX_BEGIN_NAMESPACE_VERSION
887 
888  template<typename _Rep, unsigned long long _Val>
889  struct _Checked_integral_constant
890  : integral_constant<_Rep, static_cast<_Rep>(_Val)>
891  {
892  static_assert(_Checked_integral_constant::value >= 0
893  && _Checked_integral_constant::value == _Val,
894  "literal value cannot be represented by duration type");
895  };
896 
897  template<typename _Dur, char... _Digits>
898  constexpr _Dur __check_overflow()
899  {
900  using _Val = __parse_int::_Parse_int<_Digits...>;
901  using _Rep = typename _Dur::rep;
902  // TODO: should be simply integral_constant<_Rep, _Val::value>
903  // but GCC doesn't reject narrowing conversions to _Rep.
904  using _CheckedVal = _Checked_integral_constant<_Rep, _Val::value>;
905  return _Dur{_CheckedVal::value};
906  }
907 
909  operator""h(long double __hours)
910  { return chrono::duration<long double, ratio<3600,1>>{__hours}; }
911 
912  template <char... _Digits>
913  constexpr chrono::hours
914  operator""h()
915  { return __check_overflow<chrono::hours, _Digits...>(); }
916 
918  operator""min(long double __mins)
919  { return chrono::duration<long double, ratio<60,1>>{__mins}; }
920 
921  template <char... _Digits>
922  constexpr chrono::minutes
923  operator""min()
924  { return __check_overflow<chrono::minutes, _Digits...>(); }
925 
927  operator""s(long double __secs)
928  { return chrono::duration<long double>{__secs}; }
929 
930  template <char... _Digits>
931  constexpr chrono::seconds
932  operator""s()
933  { return __check_overflow<chrono::seconds, _Digits...>(); }
934 
936  operator""ms(long double __msecs)
937  { return chrono::duration<long double, milli>{__msecs}; }
938 
939  template <char... _Digits>
940  constexpr chrono::milliseconds
941  operator""ms()
942  { return __check_overflow<chrono::milliseconds, _Digits...>(); }
943 
945  operator""us(long double __usecs)
946  { return chrono::duration<long double, micro>{__usecs}; }
947 
948  template <char... _Digits>
949  constexpr chrono::microseconds
950  operator""us()
951  { return __check_overflow<chrono::microseconds, _Digits...>(); }
952 
954  operator""ns(long double __nsecs)
955  { return chrono::duration<long double, nano>{__nsecs}; }
956 
957  template <char... _Digits>
958  constexpr chrono::nanoseconds
959  operator""ns()
960  { return __check_overflow<chrono::nanoseconds, _Digits...>(); }
961 
962  _GLIBCXX_END_NAMESPACE_VERSION
963  } // inline namespace chrono_literals
964  } // inline namespace literals
965 
966  namespace chrono
967  {
968  _GLIBCXX_BEGIN_NAMESPACE_VERSION
969 
970  using namespace literals::chrono_literals;
971 
972  _GLIBCXX_END_NAMESPACE_VERSION
973  } // namespace chrono
974 
975 #endif // __cplusplus > 201103L
976 
977  // @} group chrono
978 } // namespace std
979 
980 #endif //_GLIBCXX_USE_C99_STDINT_TR1
981 
982 #endif // C++11
983 
984 #endif //_GLIBCXX_CHRONO
duration_values
Definition: chrono:276
duration< int64_t > seconds
seconds
Definition: chrono:600
_Tp abs(const complex< _Tp > &)
Return magnitude of z.
Definition: complex:601
Provides compile-time rational arithmetic.
Definition: ratio:263
Monotonic clock.
Definition: chrono:850
duration< int64_t, nano > nanoseconds
nanoseconds
Definition: chrono:591
time_point
Definition: chrono:67
integral_constant
Definition: type_traits:69
ISO C++ entities toplevel namespace is std.
treat_as_floating_point
Definition: chrono:208
duration< int64_t, milli > milliseconds
milliseconds
Definition: chrono:597
_GLIBCXX14_CONSTEXPR const _Tp & max(const _Tp &, const _Tp &)
This does what you think it does.
Definition: stl_algobase.h:219
typename __ratio_divide< _R1, _R2 >::type ratio_divide
ratio_divide
Definition: ratio:336
constexpr enable_if< __is_duration< _ToDur >::value, _ToDur >::type duration_cast(const duration< _Rep, _Period > &__d)
duration_cast
Definition: chrono:194
constexpr enable_if< __is_duration< _ToDur >::value, time_point< _Clock, _ToDur > >::type time_point_cast(const time_point< _Clock, _Dur > &__t)
time_point_cast
Definition: chrono:667
duration
Definition: chrono:64
static constexpr _Tp lowest() noexcept
Definition: limits:327
duration< int64_t, micro > microseconds
microseconds
Definition: chrono:594
static constexpr _Tp max() noexcept
Definition: limits:321
duration< int64_t, ratio< 3600 > > hours
hours
Definition: chrono:606
_GLIBCXX14_CONSTEXPR const _Tp & min(const _Tp &, const _Tp &)
This does what you think it does.
Definition: stl_algobase.h:195
is_floating_point
Definition: type_traits:356
duration< int64_t, ratio< 60 > > minutes
minutes
Definition: chrono:603