libcxx/include/__chrono/system_clock.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_SYSTEM_CLOCK_H
  11 #define _LIBCPP___CHRONO_SYSTEM_CLOCK_H
  12
  13 #include <__chrono/duration.h>
  14 #include <__chrono/time_point.h>
  15 #include <__config>
  16 #include <ctime>
  17
  18 #if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
  19 #  pragma GCC system_header
  20 #endif
  21
  22 _LIBCPP_BEGIN_NAMESPACE_STD
  23
  24 namespace chrono {
  25
  26 class _LIBCPP_EXPORTED_FROM_ABI system_clock {
  27 public:
  28   typedef microseconds duration;
  29   typedef duration::rep rep;
  30   typedef duration::period period;
  31   typedef chrono::time_point<system_clock> time_point;
  32   static _LIBCPP_CONSTEXPR_SINCE_CXX14 const bool is_steady = false;
  33
  34   static time_point now() _NOEXCEPT;
  35   static time_t to_time_t(const time_point& __t) _NOEXCEPT;
  36   static time_point from_time_t(time_t __t) _NOEXCEPT;
  37 };
  38
  39 #if _LIBCPP_STD_VER >= 20
  40
  41 template <class _Duration>
  42 using sys_time    = time_point<system_clock, _Duration>;
  43 using sys_seconds = sys_time<seconds>;
  44 using sys_days    = sys_time<days>;
  45
  46 #endif
  47
  48 } // namespace chrono
  49
  50 _LIBCPP_END_NAMESPACE_STD
  51
  52 #endif // _LIBCPP___CHRONO_SYSTEM_CLOCK_H