diff options
Diffstat (limited to 'libcxx/include/__chrono/convert_to_timespec.h')
-rw-r--r-- | libcxx/include/__chrono/convert_to_timespec.h | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/libcxx/include/__chrono/convert_to_timespec.h b/libcxx/include/__chrono/convert_to_timespec.h new file mode 100644 index 000000000000..0106e6dec3e1 --- /dev/null +++ b/libcxx/include/__chrono/convert_to_timespec.h @@ -0,0 +1,55 @@ +// -*- C++ -*- +//===----------------------------------------------------------------------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// +#ifndef _LIBCPP___CHRONO_CONVERT_TO_TIMESPEC_H +#define _LIBCPP___CHRONO_CONVERT_TO_TIMESPEC_H + +#include <__chrono/duration.h> +#include <__config> +#include <limits> + +#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER) +#pragma GCC system_header +#endif + +_LIBCPP_PUSH_MACROS +#include <__undef_macros> + +_LIBCPP_BEGIN_NAMESPACE_STD + +// Convert a nanoseconds duration to the given TimeSpec type, which must have +// the same properties as std::timespec. +template <class _TimeSpec> +_LIBCPP_HIDE_FROM_ABI inline +_TimeSpec __convert_to_timespec(const chrono::nanoseconds& __ns) +{ + using namespace chrono; + seconds __s = duration_cast<seconds>(__ns); + _TimeSpec __ts; + typedef decltype(__ts.tv_sec) __ts_sec; + const __ts_sec __ts_sec_max = numeric_limits<__ts_sec>::max(); + + if (__s.count() < __ts_sec_max) + { + __ts.tv_sec = static_cast<__ts_sec>(__s.count()); + __ts.tv_nsec = static_cast<decltype(__ts.tv_nsec)>((__ns - __s).count()); + } + else + { + __ts.tv_sec = __ts_sec_max; + __ts.tv_nsec = 999999999; // (10^9 - 1) + } + + return __ts; +} + +_LIBCPP_END_NAMESPACE_STD + +_LIBCPP_POP_MACROS + +#endif // _LIBCPP___CHRONO_CONVERT_TO_TIMESPEC_H |