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_CONVERT_TO_TIMESPEC_H 11#define _LIBCPP___CHRONO_CONVERT_TO_TIMESPEC_H 12 13#include <__chrono/duration.h> 14#include <__config> 15#include <limits> 16 17#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) 18# pragma GCC system_header 19#endif 20 21_LIBCPP_PUSH_MACROS 22#include <__undef_macros> 23 24_LIBCPP_BEGIN_NAMESPACE_STD 25 26// Convert a nanoseconds duration to the given TimeSpec type, which must have 27// the same properties as std::timespec. 28template <class _TimeSpec> 29_LIBCPP_HIDE_FROM_ABI inline _TimeSpec __convert_to_timespec(const chrono::nanoseconds& __ns) { 30 using namespace chrono; 31 seconds __s = duration_cast<seconds>(__ns); 32 _TimeSpec __ts; 33 typedef decltype(__ts.tv_sec) __ts_sec; 34 const __ts_sec __ts_sec_max = numeric_limits<__ts_sec>::max(); 35 36 if (__s.count() < __ts_sec_max) { 37 __ts.tv_sec = static_cast<__ts_sec>(__s.count()); 38 __ts.tv_nsec = static_cast<decltype(__ts.tv_nsec)>((__ns - __s).count()); 39 } else { 40 __ts.tv_sec = __ts_sec_max; 41 __ts.tv_nsec = 999999999; // (10^9 - 1) 42 } 43 44 return __ts; 45} 46 47_LIBCPP_END_NAMESPACE_STD 48 49_LIBCPP_POP_MACROS 50 51#endif // _LIBCPP___CHRONO_CONVERT_TO_TIMESPEC_H 52