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. 28 template <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