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 >= 201703L
219 # define __cpp_lib_chrono 201611
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>>
266  abs(duration<_Rep, _Period> __d)
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
323  && (treat_as_floating_point<rep>::value
324  || !treat_as_floating_point<_Rep2>::value)>::type>
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
330  || (ratio_divide<_Period2, period>::den == 1
331  && !treat_as_floating_point<_Rep2>::value)>::type>
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>,
443  duration<_Rep2, _Period2>>::type
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>,
456  duration<_Rep2, _Period2>>::type
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
477  duration<typename __common_rep_type<_Rep1, _Rep2>::type, _Period>
478  operator*(const duration<_Rep1, _Period>& __d, const _Rep2& __s)
479  {
480  typedef duration<typename common_type<_Rep1, _Rep2>::type, _Period>
481  __cd;
482  return __cd(__cd(__d).count() * __s);
483  }
484 
485  template<typename _Rep1, typename _Rep2, typename _Period>
486  constexpr
487  duration<typename __common_rep_type<_Rep2, _Rep1>::type, _Period>
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  {
496  typedef duration<typename common_type<_Rep1, _Rep2>::type, _Period>
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  {
519  typedef duration<typename common_type<_Rep1, _Rep2>::type, _Period>
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>,
527  duration<_Rep2, _Period2>>::type
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  typename = _Require<is_convertible<_Dur2, _Dur>>>
627  constexpr time_point(const time_point<clock, _Dur2>& __t)
628  : __d(__t.time_since_epoch())
629  { }
630 
631  // observer
632  constexpr duration
633  time_since_epoch() const
634  { return __d; }
635 
636  // arithmetic
637  _GLIBCXX17_CONSTEXPR time_point&
638  operator+=(const duration& __dur)
639  {
640  __d += __dur;
641  return *this;
642  }
643 
644  _GLIBCXX17_CONSTEXPR time_point&
645  operator-=(const duration& __dur)
646  {
647  __d -= __dur;
648  return *this;
649  }
650 
651  // special values
652  static constexpr time_point
653  min()
654  { return time_point(duration::min()); }
655 
656  static constexpr time_point
657  max()
658  { return time_point(duration::max()); }
659 
660  private:
661  duration __d;
662  };
663 
664  /// time_point_cast
665  template<typename _ToDur, typename _Clock, typename _Dur>
666  constexpr typename enable_if<__is_duration<_ToDur>::value,
667  time_point<_Clock, _ToDur>>::type
669  {
670  typedef time_point<_Clock, _ToDur> __time_point;
671  return __time_point(duration_cast<_ToDur>(__t.time_since_epoch()));
672  }
673 
674 #if __cplusplus > 201402L
675  template<typename _ToDur, typename _Clock, typename _Dur>
676  constexpr
677  enable_if_t<__is_duration<_ToDur>::value, time_point<_Clock, _ToDur>>
678  floor(const time_point<_Clock, _Dur>& __tp)
679  {
680  return time_point<_Clock, _ToDur>{
681  chrono::floor<_ToDur>(__tp.time_since_epoch())};
682  }
683 
684  template<typename _ToDur, typename _Clock, typename _Dur>
685  constexpr
686  enable_if_t<__is_duration<_ToDur>::value, time_point<_Clock, _ToDur>>
687  ceil(const time_point<_Clock, _Dur>& __tp)
688  {
689  return time_point<_Clock, _ToDur>{
690  chrono::ceil<_ToDur>(__tp.time_since_epoch())};
691  }
692 
693  template<typename _ToDur, typename _Clock, typename _Dur>
694  constexpr enable_if_t<
695  __and_<__is_duration<_ToDur>,
696  __not_<treat_as_floating_point<typename _ToDur::rep>>>::value,
697  time_point<_Clock, _ToDur>>
698  round(const time_point<_Clock, _Dur>& __tp)
699  {
700  return time_point<_Clock, _ToDur>{
701  chrono::round<_ToDur>(__tp.time_since_epoch())};
702  }
703 #endif // C++17
704 
705  template<typename _Clock, typename _Dur1,
706  typename _Rep2, typename _Period2>
707  constexpr time_point<_Clock,
708  typename common_type<_Dur1, duration<_Rep2, _Period2>>::type>
709  operator+(const time_point<_Clock, _Dur1>& __lhs,
710  const duration<_Rep2, _Period2>& __rhs)
711  {
712  typedef duration<_Rep2, _Period2> __dur2;
713  typedef typename common_type<_Dur1,__dur2>::type __ct;
714  typedef time_point<_Clock, __ct> __time_point;
715  return __time_point(__lhs.time_since_epoch() + __rhs);
716  }
717 
718  template<typename _Rep1, typename _Period1,
719  typename _Clock, typename _Dur2>
720  constexpr time_point<_Clock,
721  typename common_type<duration<_Rep1, _Period1>, _Dur2>::type>
722  operator+(const duration<_Rep1, _Period1>& __lhs,
723  const time_point<_Clock, _Dur2>& __rhs)
724  {
725  typedef duration<_Rep1, _Period1> __dur1;
726  typedef typename common_type<__dur1,_Dur2>::type __ct;
727  typedef time_point<_Clock, __ct> __time_point;
728  return __time_point(__rhs.time_since_epoch() + __lhs);
729  }
730 
731  template<typename _Clock, typename _Dur1,
732  typename _Rep2, typename _Period2>
733  constexpr time_point<_Clock,
734  typename common_type<_Dur1, duration<_Rep2, _Period2>>::type>
735  operator-(const time_point<_Clock, _Dur1>& __lhs,
736  const duration<_Rep2, _Period2>& __rhs)
737  {
738  typedef duration<_Rep2, _Period2> __dur2;
739  typedef typename common_type<_Dur1,__dur2>::type __ct;
740  typedef time_point<_Clock, __ct> __time_point;
741  return __time_point(__lhs.time_since_epoch() -__rhs);
742  }
743 
744  template<typename _Clock, typename _Dur1, typename _Dur2>
745  constexpr typename common_type<_Dur1, _Dur2>::type
746  operator-(const time_point<_Clock, _Dur1>& __lhs,
747  const time_point<_Clock, _Dur2>& __rhs)
748  { return __lhs.time_since_epoch() - __rhs.time_since_epoch(); }
749 
750  template<typename _Clock, typename _Dur1, typename _Dur2>
751  constexpr bool
752  operator==(const time_point<_Clock, _Dur1>& __lhs,
753  const time_point<_Clock, _Dur2>& __rhs)
754  { return __lhs.time_since_epoch() == __rhs.time_since_epoch(); }
755 
756  template<typename _Clock, typename _Dur1, typename _Dur2>
757  constexpr bool
758  operator!=(const time_point<_Clock, _Dur1>& __lhs,
759  const time_point<_Clock, _Dur2>& __rhs)
760  { return !(__lhs == __rhs); }
761 
762  template<typename _Clock, typename _Dur1, typename _Dur2>
763  constexpr bool
764  operator<(const time_point<_Clock, _Dur1>& __lhs,
765  const time_point<_Clock, _Dur2>& __rhs)
766  { return __lhs.time_since_epoch() < __rhs.time_since_epoch(); }
767 
768  template<typename _Clock, typename _Dur1, typename _Dur2>
769  constexpr bool
770  operator<=(const time_point<_Clock, _Dur1>& __lhs,
771  const time_point<_Clock, _Dur2>& __rhs)
772  { return !(__rhs < __lhs); }
773 
774  template<typename _Clock, typename _Dur1, typename _Dur2>
775  constexpr bool
776  operator>(const time_point<_Clock, _Dur1>& __lhs,
777  const time_point<_Clock, _Dur2>& __rhs)
778  { return __rhs < __lhs; }
779 
780  template<typename _Clock, typename _Dur1, typename _Dur2>
781  constexpr bool
782  operator>=(const time_point<_Clock, _Dur1>& __lhs,
783  const time_point<_Clock, _Dur2>& __rhs)
784  { return !(__lhs < __rhs); }
785 
786 
787  // Clocks.
788 
789  // Why nanosecond resolution as the default?
790  // Why have std::system_clock always count in the highest
791  // resolution (ie nanoseconds), even if on some OSes the low 3
792  // or 9 decimal digits will be always zero? This allows later
793  // implementations to change the system_clock::now()
794  // implementation any time to provide better resolution without
795  // changing function signature or units.
796 
797  // To support the (forward) evolution of the library's defined
798  // clocks, wrap inside inline namespace so that the current
799  // defintions of system_clock, steady_clock, and
800  // high_resolution_clock types are uniquely mangled. This way, new
801  // code can use the latests clocks, while the library can contain
802  // compatibility definitions for previous versions. At some
803  // point, when these clocks settle down, the inlined namespaces
804  // can be removed. XXX GLIBCXX_ABI Deprecated
805  inline namespace _V2 {
806 
807  /**
808  * @brief System clock.
809  *
810  * Time returned represents wall time from the system-wide clock.
811  */
813  {
815  typedef duration::rep rep;
816  typedef duration::period period;
818 
819  static_assert(system_clock::duration::min()
820  < system_clock::duration::zero(),
821  "a clock's minimum duration cannot be less than its epoch");
822 
823  static constexpr bool is_steady = false;
824 
825  static time_point
826  now() noexcept;
827 
828  // Map to C API
829  static std::time_t
830  to_time_t(const time_point& __t) noexcept
831  {
832  return std::time_t(duration_cast<chrono::seconds>
833  (__t.time_since_epoch()).count());
834  }
835 
836  static time_point
837  from_time_t(std::time_t __t) noexcept
838  {
841  (__from(chrono::seconds(__t)));
842  }
843  };
844 
845 
846  /**
847  * @brief Monotonic clock
848  *
849  * Time returned has the property of only increasing at a uniform rate.
850  */
852  {
854  typedef duration::rep rep;
855  typedef duration::period period;
857 
858  static constexpr bool is_steady = true;
859 
860  static time_point
861  now() noexcept;
862  };
863 
864 
865  /**
866  * @brief Highest-resolution clock
867  *
868  * This is the clock "with the shortest tick period." Alias to
869  * std::system_clock until higher-than-nanosecond definitions
870  * become feasible.
871  */
873 
874  } // end inline namespace _V2
875 
876  _GLIBCXX_END_NAMESPACE_VERSION
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  _GLIBCXX_BEGIN_NAMESPACE_VERSION
888 
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  _GLIBCXX_END_NAMESPACE_VERSION
964  } // inline namespace chrono_literals
965  } // inline namespace literals
966 
967  namespace chrono
968  {
969  _GLIBCXX_BEGIN_NAMESPACE_VERSION
970 
971  using namespace literals::chrono_literals;
972 
973  _GLIBCXX_END_NAMESPACE_VERSION
974  } // namespace chrono
975 
976 #endif // __cplusplus > 201103L
977 
978  // @} group chrono
979 } // namespace std
980 
981 #endif //_GLIBCXX_USE_C99_STDINT_TR1
982 
983 #endif // C++11
984 
985 #endif //_GLIBCXX_CHRONO
complex< _Tp > operator-(const complex< _Tp > &__x, const complex< _Tp > &__y)
Return new complex value x minus y.
Definition: complex:356
treat_as_floating_point
Definition: chrono:208
_GLIBCXX14_CONSTEXPR const _Tp & min(const _Tp &, const _Tp &)
This does what you think it does.
Definition: stl_algobase.h:195
static constexpr _Tp lowest() noexcept
Definition: limits:327
complex< _Tp > operator+(const complex< _Tp > &__x, const complex< _Tp > &__y)
Return new complex value x plus y.
Definition: complex:326
complex< _Tp > operator/(const complex< _Tp > &__x, const complex< _Tp > &__y)
Return new complex value x divided by y.
Definition: complex:416
time_point
Definition: chrono:67
Provides compile-time rational arithmetic.
Definition: ratio:263
is_floating_point
Definition: type_traits:353
_GLIBCXX14_CONSTEXPR const _Tp & max(const _Tp &, const _Tp &)
This does what you think it does.
Definition: stl_algobase.h:219
Monotonic clock.
Definition: chrono:851
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
duration< int64_t > seconds
seconds
Definition: chrono:600
complex< _Tp > operator*(const complex< _Tp > &__x, const complex< _Tp > &__y)
Return new complex value x times y.
Definition: complex:386
duration< int64_t, nano > nanoseconds
nanoseconds
Definition: chrono:591
duration< int64_t, ratio< 3600 > > hours
hours
Definition: chrono:606
duration_values
Definition: chrono:276
duration< int64_t, milli > milliseconds
milliseconds
Definition: chrono:597
integral_constant
Definition: type_traits:69
_Tp abs(const complex< _Tp > &)
Return magnitude of z.
Definition: complex:603
duration< int64_t, ratio< 60 > > minutes
minutes
Definition: chrono:603
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:668
duration
Definition: chrono:64
duration< int64_t, micro > microseconds
microseconds
Definition: chrono:594
static constexpr _Tp max() noexcept
Definition: limits:321