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 template <class _Duration>
  30 class hh_mm_ss {
  31 private:
  32   static_assert(__is_duration_v<_Duration>, "template parameter of hh_mm_ss must be a std::chrono::duration");
  33   using __CommonType = common_type_t<_Duration, chrono::seconds>;
  34
  35   _LIBCPP_HIDE_FROM_ABI static constexpr uint64_t __pow10(unsigned __exp) {
  36     uint64_t __ret = 1;
  37     for (unsigned __i = 0; __i < __exp; ++__i)
  38       __ret *= 10U;
  39     return __ret;
  40   }
  41
  42   _LIBCPP_HIDE_FROM_ABI static constexpr unsigned __width(uint64_t __n, uint64_t __d = 10, unsigned __w = 0) {
  43     if (__n >= 2 && __d != 0 && __w < 19)
  44       return 1 + __width(__n, __d % __n * 10, __w + 1);
  45     return 0;
  46   }
  47
  48 public:
  49   _LIBCPP_HIDE_FROM_ABI static unsigned constexpr fractional_width =
  50       __width(__CommonType::period::den) < 19 ? __width(__CommonType::period::den) : 6u;
  51   using precision = duration<typename __CommonType::rep, ratio<1, __pow10(fractional_width)>>;
  52
  53   _LIBCPP_HIDE_FROM_ABI constexpr hh_mm_ss() noexcept : hh_mm_ss{_Duration::zero()} {}
  54
  55   _LIBCPP_HIDE_FROM_ABI constexpr explicit hh_mm_ss(_Duration __d) noexcept
  56       : __is_neg_(__d < _Duration(0)),
  57         __h_(chrono::duration_cast<chrono::hours>(chrono::abs(__d))),
  58         __m_(chrono::duration_cast<chrono::minutes>(chrono::abs(__d) - hours())),
  59         __s_(chrono::duration_cast<chrono::seconds>(chrono::abs(__d) - hours() - minutes())),
  60         __f_(chrono::duration_cast<precision>(chrono::abs(__d) - hours() - minutes() - seconds())) {}
  61
  62   _LIBCPP_HIDE_FROM_ABI constexpr bool is_negative() const noexcept { return __is_neg_; }
  63   _LIBCPP_HIDE_FROM_ABI constexpr chrono::hours hours() const noexcept { return __h_; }
  64   _LIBCPP_HIDE_FROM_ABI constexpr chrono::minutes minutes() const noexcept { return __m_; }
  65   _LIBCPP_HIDE_FROM_ABI constexpr chrono::seconds seconds() const noexcept { return __s_; }
  66   _LIBCPP_HIDE_FROM_ABI constexpr precision subseconds() const noexcept { return __f_; }
  67
  68   _LIBCPP_HIDE_FROM_ABI constexpr precision to_duration() const noexcept {
  69     auto __dur = __h_ + __m_ + __s_ + __f_;
  70     return __is_neg_ ? -__dur : __dur;
  71   }
  72
  73   _LIBCPP_HIDE_FROM_ABI constexpr explicit operator precision() const noexcept { return to_duration(); }
  74
  75 private:
  76   bool __is_neg_;
  77   chrono::hours __h_;
  78   chrono::minutes __m_;
  79   chrono::seconds __s_;
  80   precision __f_;
  81 };
  82 _LIBCPP_CTAD_SUPPORTED_FOR_TYPE(hh_mm_ss);
  83
  84 _LIBCPP_HIDE_FROM_ABI inline constexpr bool is_am(const hours& __h) noexcept {
  85   return __h >= hours(0) && __h < hours(12);
  86 }
  87 _LIBCPP_HIDE_FROM_ABI inline constexpr bool is_pm(const hours& __h) noexcept {
  88   return __h >= hours(12) && __h < hours(24);
  89 }
  90
  91 _LIBCPP_HIDE_FROM_ABI inline constexpr hours make12(const hours& __h) noexcept {
  92   if (__h == hours(0))
  93     return hours(12);
  94   else if (__h <= hours(12))
  95     return __h;
  96   else
  97     return __h - hours(12);
  98 }
  99
 100 _LIBCPP_HIDE_FROM_ABI inline constexpr hours make24(const hours& __h, bool __is_pm) noexcept {
 101   if (__is_pm)
 102     return __h == hours(12) ? __h : __h + hours(12);
 103   else
 104     return __h == hours(12) ? hours(0) : __h;
 105 }
 106 } // namespace chrono
 107
 108 _LIBCPP_END_NAMESPACE_STD
 109
 110 #endif // _LIBCPP_STD_VER >= 20
 111
 112 #endif // _LIBCPP___CHRONO_HH_MM_SS_H