libcxx/include/__chrono/hh_mm_ss.h

   1 // -*- C++ -*-
   2 //===----------------------------------------------------------------------===//
   3 //
   4 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   5 // See https://llvm.org/LICENSE.txt for license information.
   6 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #ifndef _LIBCPP___CHRONO_HH_MM_SS_H
  11 #define _LIBCPP___CHRONO_HH_MM_SS_H
  12
  13 #include <__chrono/duration.h>
  14 #include <__chrono/time_point.h>
  15 #include <__config>
  16 #include <__type_traits/common_type.h>
  17 #include <ratio>
  18
  19 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  20 #  pragma GCC system_header
  21 #endif
  22
  23 #if _LIBCPP_STD_VER >= 20
  24
  25 _LIBCPP_BEGIN_NAMESPACE_STD
  26
  27 namespace chrono
  28 {
  29
  30 template <class _Duration>
  31 class hh_mm_ss
  32 {
  33 private:
  34     static_assert(__is_duration<_Duration>::value, "template parameter of hh_mm_ss must be a std::chrono::duration");
  35     using __CommonType = common_type_t<_Duration, chrono::seconds>;
  36
  37     _LIBCPP_HIDE_FROM_ABI static constexpr uint64_t __pow10(unsigned __exp)
  38     {
  39         uint64_t __ret = 1;
  40         for (unsigned __i = 0; __i < __exp; ++__i)
  41             __ret *= 10U;
  42         return __ret;
  43     }
  44
  45     _LIBCPP_HIDE_FROM_ABI static constexpr unsigned __width(uint64_t __n, uint64_t __d = 10, unsigned __w = 0)
  46     {
  47         if (__n >= 2 && __d != 0 && __w < 19)
  48             return 1 + __width(__n, __d % __n * 10, __w+1);
  49         return 0;
  50     }
  51
  52 public:
  53     _LIBCPP_HIDE_FROM_ABI static unsigned constexpr fractional_width = __width(__CommonType::period::den) < 19 ?
  54                                                  __width(__CommonType::period::den) : 6u;
  55     using precision = duration<typename __CommonType::rep, ratio<1, __pow10(fractional_width)>>;
  56
  57     _LIBCPP_HIDE_FROM_ABI constexpr hh_mm_ss() noexcept : hh_mm_ss{_Duration::zero()} {}
  58
  59     _LIBCPP_HIDE_FROM_ABI constexpr explicit hh_mm_ss(_Duration __d) noexcept :
  60         __is_neg_(__d < _Duration(0)),
  61         __h_(chrono::duration_cast<chrono::hours>  (chrono::abs(__d))),
  62         __m_(chrono::duration_cast<chrono::minutes>(chrono::abs(__d) - hours())),
  63         __s_(chrono::duration_cast<chrono::seconds>(chrono::abs(__d) - hours() - minutes())),
  64         __f_(chrono::duration_cast<precision>      (chrono::abs(__d) - hours() - minutes() - seconds()))
  65         {}
  66
  67     _LIBCPP_HIDE_FROM_ABI constexpr bool is_negative()        const noexcept { return __is_neg_; }
  68     _LIBCPP_HIDE_FROM_ABI constexpr chrono::hours hours()     const noexcept { return __h_; }
  69     _LIBCPP_HIDE_FROM_ABI constexpr chrono::minutes minutes() const noexcept { return __m_; }
  70     _LIBCPP_HIDE_FROM_ABI constexpr chrono::seconds seconds() const noexcept { return __s_; }
  71     _LIBCPP_HIDE_FROM_ABI constexpr precision subseconds()    const noexcept { return __f_; }
  72
  73     _LIBCPP_HIDE_FROM_ABI constexpr precision to_duration() const noexcept
  74     {
  75         auto __dur = __h_ + __m_ + __s_ + __f_;
  76         return __is_neg_ ? -__dur : __dur;
  77     }
  78
  79     _LIBCPP_HIDE_FROM_ABI constexpr explicit operator precision() const noexcept { return to_duration(); }
  80
  81 private:
  82     bool            __is_neg_;
  83     chrono::hours   __h_;
  84     chrono::minutes __m_;
  85     chrono::seconds __s_;
  86     precision       __f_;
  87 };
  88 _LIBCPP_CTAD_SUPPORTED_FOR_TYPE(hh_mm_ss);
  89
  90 _LIBCPP_HIDE_FROM_ABI constexpr bool is_am(const hours& __h) noexcept { return __h >= hours( 0) && __h < hours(12); }
  91 _LIBCPP_HIDE_FROM_ABI constexpr bool is_pm(const hours& __h) noexcept { return __h >= hours(12) && __h < hours(24); }
  92
  93 _LIBCPP_HIDE_FROM_ABI constexpr hours make12(const hours& __h) noexcept
  94 {
  95     if      (__h == hours( 0)) return hours(12);
  96     else if (__h <= hours(12)) return __h;
  97     else                       return __h - hours(12);
  98 }
  99
 100 _LIBCPP_HIDE_FROM_ABI constexpr hours make24(const hours& __h, bool __is_pm) noexcept
 101 {
 102     if (__is_pm)
 103         return __h == hours(12) ? __h : __h + hours(12);
 104     else
 105         return __h == hours(12) ? hours(0) : __h;
 106 }
 107 } // namespace chrono
 108
 109 _LIBCPP_END_NAMESPACE_STD
 110
 111 #endif // _LIBCPP_STD_VER >= 20
 112
 113 #endif // _LIBCPP___CHRONO_HH_MM_SS_H