[libcxx] r337960 - [libc++] Use __int128_t to represent file_time_type.

Eric Fiselier via cfe-commits cfe-commits at lists.llvm.org
Wed Jul 25 15:03:00 PDT 2018


On Wed, Jul 25, 2018 at 3:39 PM Alex L <arphaman at gmail.com> wrote:

> Looks like this works:
>
> +++ b/src/experimental/filesystem/filesystem_common.h
> @@ -393,7 +393,7 @@ bool set_file_times(const path& p,
> std::array<TimeSpec, 2> const& TS,
>                      error_code& ec) {
>  #if !defined(_LIBCPP_USE_UTIMENSAT)
>    using namespace chrono;
> -  auto Convert = [](long nsec) {
> +  auto Convert = [](long nsec) ->
> decltype(std::declval<::timeval>().tv_usec) {
>      return duration_cast<microseconds>(nanoseconds(nsec)).count();
>    };
>    struct ::timeval ConvertedTS[2] = {{TS[0].tv_sec,
> Convert(TS[0].tv_nsec)},
>
> I will commit this fix in a couple of minutes.
>

I think I would prefer an explicit cast to an implicit one since the
narrowing is intended, and should be safe.

Maybe:

auto Convert [](long nsec) {
  using int_type = decltype(::timeval::tv_usec);
  auto dur = duration_cast<microseconds>(nanoseconds(nsec)).count();
  return static_cast<int_type>(dur);
};

?

>
> On 25 July 2018 at 14:27, Eric Fiselier <eric at efcs.ca> wrote:
>
>> Thanks. let me know if you want me to take over
>>
>> On Wed, Jul 25, 2018, 3:22 PM Alex L, <arphaman at gmail.com> wrote:
>>
>>>
>>>
>>> On 25 July 2018 at 13:51, Eric Fiselier via cfe-commits <
>>> cfe-commits at lists.llvm.org> wrote:
>>>
>>>> Author: ericwf
>>>> Date: Wed Jul 25 13:51:49 2018
>>>> New Revision: 337960
>>>>
>>>> URL: http://llvm.org/viewvc/llvm-project?rev=337960&view=rev
>>>> Log:
>>>> [libc++] Use __int128_t to represent file_time_type.
>>>>
>>>> Summary:
>>>> The ``file_time_type`` time point is used to represent the write times
>>>> for files.
>>>> Its job is to act as part of a C++ wrapper for less ideal system
>>>> interfaces. The
>>>> underlying filesystem uses the ``timespec`` struct for the same purpose.
>>>>
>>>> However, the initial implementation of ``file_time_type`` could not
>>>> represent
>>>> either the range or resolution of ``timespec``, making it unsuitable.
>>>> Fixing
>>>> this requires an implementation which uses more than 64 bits to store
>>>> the
>>>> time point.
>>>>
>>>> I primarily considered two solutions: Using ``__int128_t`` and using a
>>>> arithmetic emulation of ``timespec``. Each has its pros and cons, and
>>>> both
>>>> come with more than one complication.
>>>>
>>>> However, after a lot of consideration, I decided on using `__int128_t`.
>>>> This patch implements that change.
>>>>
>>>> Please see the [FileTimeType Design Document](
>>>> http://libcxx.llvm.org/docs/DesignDocs/FileTimeType.html) for more
>>>> information.
>>>>
>>>> Reviewers: mclow.lists, ldionne, joerg, arthur.j.odwyer, EricWF
>>>>
>>>> Reviewed By: EricWF
>>>>
>>>> Subscribers: christof, K-ballo, cfe-commits, BillyONeal
>>>>
>>>> Differential Revision: https://reviews.llvm.org/D49774
>>>>
>>>> Added:
>>>>     libcxx/trunk/src/include/apple_availability.h
>>>> Modified:
>>>>     libcxx/trunk/include/experimental/filesystem
>>>>     libcxx/trunk/src/chrono.cpp
>>>>     libcxx/trunk/src/experimental/filesystem/filesystem_common.h
>>>>     libcxx/trunk/src/experimental/filesystem/operations.cpp
>>>>
>>>> libcxx/trunk/test/libcxx/experimental/filesystem/class.directory_entry/directory_entry.mods/last_write_time.sh.cpp
>>>>
>>>> libcxx/trunk/test/libcxx/experimental/filesystem/convert_file_time.sh.cpp
>>>>
>>>> libcxx/trunk/test/std/experimental/filesystem/fs.filesystem.synopsis/file_time_type.pass.cpp
>>>>
>>>> libcxx/trunk/test/std/experimental/filesystem/fs.op.funcs/fs.op.last_write_time/last_write_time.pass.cpp
>>>>
>>>> Modified: libcxx/trunk/include/experimental/filesystem
>>>> URL:
>>>> http://llvm.org/viewvc/llvm-project/libcxx/trunk/include/experimental/filesystem?rev=337960&r1=337959&r2=337960&view=diff
>>>>
>>>> ==============================================================================
>>>> --- libcxx/trunk/include/experimental/filesystem (original)
>>>> +++ libcxx/trunk/include/experimental/filesystem Wed Jul 25 13:51:49
>>>> 2018
>>>> @@ -260,7 +260,37 @@ _LIBCPP_PUSH_MACROS
>>>>
>>>>  _LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL_FILESYSTEM
>>>>
>>>> -typedef chrono::time_point<std::chrono::system_clock>  file_time_type;
>>>> +struct _FilesystemClock {
>>>> +#if !defined(_LIBCPP_HAS_NO_INT128)
>>>> +  typedef __int128_t rep;
>>>> +  typedef nano period;
>>>> +#else
>>>> +  typedef long long rep;
>>>> +  typedef nano period;
>>>> +#endif
>>>> +
>>>> +  typedef chrono::duration<rep, period> duration;
>>>> +  typedef chrono::time_point<_FilesystemClock> time_point;
>>>> +
>>>> +  static _LIBCPP_CONSTEXPR_AFTER_CXX11 const bool is_steady = false;
>>>> +
>>>> +  _LIBCPP_FUNC_VIS static time_point now() noexcept;
>>>> +
>>>> +  _LIBCPP_INLINE_VISIBILITY
>>>> +  static time_t to_time_t(const time_point& __t) noexcept {
>>>> +    typedef chrono::duration<rep> __secs;
>>>> +    return time_t(
>>>> +        chrono::duration_cast<__secs>(__t.time_since_epoch()).count());
>>>> +  }
>>>> +
>>>> +  _LIBCPP_INLINE_VISIBILITY
>>>> +  static time_point from_time_t(time_t __t) noexcept {
>>>> +    typedef chrono::duration<rep> __secs;
>>>> +    return time_point(__secs(__t));
>>>> +  }
>>>> +};
>>>> +
>>>> +typedef chrono::time_point<_FilesystemClock> file_time_type;
>>>>
>>>>  struct _LIBCPP_TYPE_VIS space_info
>>>>  {
>>>>
>>>> Modified: libcxx/trunk/src/chrono.cpp
>>>> URL:
>>>> http://llvm.org/viewvc/llvm-project/libcxx/trunk/src/chrono.cpp?rev=337960&r1=337959&r2=337960&view=diff
>>>>
>>>> ==============================================================================
>>>> --- libcxx/trunk/src/chrono.cpp (original)
>>>> +++ libcxx/trunk/src/chrono.cpp Wed Jul 25 13:51:49 2018
>>>> @@ -11,27 +11,10 @@
>>>>  #include "cerrno"        // errno
>>>>  #include "system_error"  // __throw_system_error
>>>>  #include <time.h>        // clock_gettime, CLOCK_MONOTONIC and
>>>> CLOCK_REALTIME
>>>> +#include "include/apple_availability.h"
>>>>
>>>> -#if (__APPLE__)
>>>> -#if defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__)
>>>> -#if __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ >= 101200
>>>> -#define _LIBCXX_USE_CLOCK_GETTIME
>>>> -#endif
>>>> -#elif defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__)
>>>> -#if __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ >= 100000
>>>> -#define _LIBCXX_USE_CLOCK_GETTIME
>>>> -#endif
>>>> -#elif defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__)
>>>> -#if __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ >= 100000
>>>> -#define _LIBCXX_USE_CLOCK_GETTIME
>>>> -#endif
>>>> -#elif defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__)
>>>> -#if __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ >= 30000
>>>> -#define _LIBCXX_USE_CLOCK_GETTIME
>>>> -#endif
>>>> -#endif // __ENVIRONMENT_.*_VERSION_MIN_REQUIRED__
>>>> -#else
>>>> -#define _LIBCXX_USE_CLOCK_GETTIME
>>>> +#if !defined(__APPLE__)
>>>> +#define _LIBCPP_USE_CLOCK_GETTIME
>>>>  #endif // __APPLE__
>>>>
>>>>  #if defined(_LIBCPP_WIN32API)
>>>> @@ -42,7 +25,7 @@
>>>>  #include <winapifamily.h>
>>>>  #endif
>>>>  #else
>>>> -#if !defined(CLOCK_REALTIME) || !defined(_LIBCXX_USE_CLOCK_GETTIME)
>>>> +#if !defined(CLOCK_REALTIME) || !defined(_LIBCPP_USE_CLOCK_GETTIME)
>>>>  #include <sys/time.h>        // for gettimeofday and timeval
>>>>  #endif // !defined(CLOCK_REALTIME)
>>>>  #endif // defined(_LIBCPP_WIN32API)
>>>> @@ -92,16 +75,16 @@ system_clock::now() _NOEXCEPT
>>>>                         static_cast<__int64>(ft.dwLowDateTime)};
>>>>    return time_point(duration_cast<duration>(d - nt_to_unix_epoch));
>>>>  #else
>>>> -#if defined(_LIBCXX_USE_CLOCK_GETTIME) && defined(CLOCK_REALTIME)
>>>> -    struct timespec tp;
>>>> -    if (0 != clock_gettime(CLOCK_REALTIME, &tp))
>>>> -        __throw_system_error(errno, "clock_gettime(CLOCK_REALTIME)
>>>> failed");
>>>> -    return time_point(seconds(tp.tv_sec) + microseconds(tp.tv_nsec /
>>>> 1000));
>>>> +#if defined(_LIBCPP_USE_CLOCK_GETTIME) && defined(CLOCK_REALTIME)
>>>> +  struct timespec tp;
>>>> +  if (0 != clock_gettime(CLOCK_REALTIME, &tp))
>>>> +    __throw_system_error(errno, "clock_gettime(CLOCK_REALTIME)
>>>> failed");
>>>> +  return time_point(seconds(tp.tv_sec) + microseconds(tp.tv_nsec /
>>>> 1000));
>>>>  #else
>>>>      timeval tv;
>>>>      gettimeofday(&tv, 0);
>>>>      return time_point(seconds(tv.tv_sec) + microseconds(tv.tv_usec));
>>>> -#endif // _LIBCXX_USE_CLOCK_GETTIME && CLOCK_REALTIME
>>>> +#endif // _LIBCPP_USE_CLOCK_GETTIME && CLOCK_REALTIME
>>>>  #endif
>>>>  }
>>>>
>>>> @@ -129,7 +112,7 @@ const bool steady_clock::is_steady;
>>>>  #if defined(__APPLE__)
>>>>
>>>>  // Darwin libc versions >= 1133 provide ns precision via
>>>> CLOCK_UPTIME_RAW
>>>> -#if defined(_LIBCXX_USE_CLOCK_GETTIME) && defined(CLOCK_UPTIME_RAW)
>>>> +#if defined(_LIBCPP_USE_CLOCK_GETTIME) && defined(CLOCK_UPTIME_RAW)
>>>>  steady_clock::time_point
>>>>  steady_clock::now() _NOEXCEPT
>>>>  {
>>>> @@ -191,7 +174,7 @@ steady_clock::now() _NOEXCEPT
>>>>      static FP fp = init_steady_clock();
>>>>      return time_point(duration(fp()));
>>>>  }
>>>> -#endif // defined(_LIBCXX_USE_CLOCK_GETTIME) &&
>>>> defined(CLOCK_UPTIME_RAW)
>>>> +#endif // defined(_LIBCPP_USE_CLOCK_GETTIME) &&
>>>> defined(CLOCK_UPTIME_RAW)
>>>>
>>>>  #elif defined(_LIBCPP_WIN32API)
>>>>
>>>>
>>>> Modified: libcxx/trunk/src/experimental/filesystem/filesystem_common.h
>>>> URL:
>>>> http://llvm.org/viewvc/llvm-project/libcxx/trunk/src/experimental/filesystem/filesystem_common.h?rev=337960&r1=337959&r2=337960&view=diff
>>>>
>>>> ==============================================================================
>>>> --- libcxx/trunk/src/experimental/filesystem/filesystem_common.h
>>>> (original)
>>>> +++ libcxx/trunk/src/experimental/filesystem/filesystem_common.h Wed
>>>> Jul 25 13:51:49 2018
>>>> @@ -23,33 +23,17 @@
>>>>
>>>>  #include <experimental/filesystem>
>>>>
>>>> -#if (__APPLE__)
>>>> -#if defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__)
>>>> -#if __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ >= 101300
>>>> -#define _LIBCXX_USE_UTIMENSAT
>>>> -#endif
>>>> -#elif defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__)
>>>> -#if __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ >= 110000
>>>> -#define _LIBCXX_USE_UTIMENSAT
>>>> -#endif
>>>> -#elif defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__)
>>>> -#if __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ >= 110000
>>>> -#define _LIBCXX_USE_UTIMENSAT
>>>> -#endif
>>>> -#elif defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__)
>>>> -#if __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ >= 40000
>>>> -#define _LIBCXX_USE_UTIMENSAT
>>>> -#endif
>>>> -#endif // __ENVIRONMENT_.*_VERSION_MIN_REQUIRED__
>>>> -#else
>>>> +#include "../../include/apple_availability.h"
>>>> +
>>>> +#if !defined(__APPLE__)
>>>>  // We can use the presence of UTIME_OMIT to detect platforms that
>>>> provide
>>>>  // utimensat.
>>>>  #if defined(UTIME_OMIT)
>>>> -#define _LIBCXX_USE_UTIMENSAT
>>>> +#define _LIBCPP_USE_UTIMENSAT
>>>> +#endif
>>>>  #endif
>>>> -#endif // __APPLE__
>>>>
>>>> -#if !defined(_LIBCXX_USE_UTIMENSAT)
>>>> +#if !defined(_LIBCPP_USE_UTIMENSAT)
>>>>  #include <sys/time.h> // for ::utimes as used in __last_write_time
>>>>  #endif
>>>>
>>>> @@ -212,76 +196,119 @@ private:
>>>>    ErrorHandler& operator=(ErrorHandler const&) = delete;
>>>>  };
>>>>
>>>> -namespace time_util {
>>>> +using chrono::duration;
>>>> +using chrono::duration_cast;
>>>>
>>>> -using namespace chrono;
>>>> +using TimeSpec = struct ::timespec;
>>>> +using StatT = struct ::stat;
>>>>
>>>> -template <class FileTimeT,
>>>> +template <class FileTimeT, class TimeT,
>>>>            bool IsFloat = is_floating_point<typename
>>>> FileTimeT::rep>::value>
>>>> -struct fs_time_util_base {
>>>> -  static constexpr seconds::rep max_seconds =
>>>> -      duration_cast<seconds>(FileTimeT::duration::max()).count();
>>>> -
>>>> -  static constexpr nanoseconds::rep max_nsec =
>>>> -      duration_cast<nanoseconds>(FileTimeT::duration::max() -
>>>> -                                 seconds(max_seconds))
>>>> +struct time_util_base {
>>>> +  using rep = typename FileTimeT::rep;
>>>> +  using fs_duration = typename FileTimeT::duration;
>>>> +  using fs_seconds = duration<rep>;
>>>> +  using fs_nanoseconds = duration<rep, nano>;
>>>> +  using fs_microseconds = duration<rep, micro>;
>>>> +
>>>> +  static constexpr rep max_seconds =
>>>> +      duration_cast<fs_seconds>(FileTimeT::duration::max()).count();
>>>> +
>>>> +  static constexpr rep max_nsec =
>>>> +      duration_cast<fs_nanoseconds>(FileTimeT::duration::max() -
>>>> +                                    fs_seconds(max_seconds))
>>>>            .count();
>>>>
>>>> -  static constexpr seconds::rep min_seconds =
>>>> -      duration_cast<seconds>(FileTimeT::duration::min()).count();
>>>> +  static constexpr rep min_seconds =
>>>> +      duration_cast<fs_seconds>(FileTimeT::duration::min()).count();
>>>>
>>>> -  static constexpr nanoseconds::rep min_nsec_timespec =
>>>> -      duration_cast<nanoseconds>(
>>>> -          (FileTimeT::duration::min() - seconds(min_seconds)) +
>>>> seconds(1))
>>>> +  static constexpr rep min_nsec_timespec =
>>>> +      duration_cast<fs_nanoseconds>(
>>>> +          (FileTimeT::duration::min() - fs_seconds(min_seconds)) +
>>>> +          fs_seconds(1))
>>>>            .count();
>>>>
>>>> +private:
>>>> +#if _LIBCPP_STD_VER > 11
>>>> +  static constexpr fs_duration get_min_nsecs() {
>>>> +    return duration_cast<fs_duration>(
>>>> +        fs_nanoseconds(min_nsec_timespec) -
>>>> +        duration_cast<fs_nanoseconds>(fs_seconds(1)));
>>>> +  }
>>>>    // Static assert that these values properly round trip.
>>>> -  static_assert((seconds(min_seconds) +
>>>> -
>>>>  duration_cast<microseconds>(nanoseconds(min_nsec_timespec))) -
>>>> -                        duration_cast<microseconds>(seconds(1)) ==
>>>> +  static_assert(fs_seconds(min_seconds) + get_min_nsecs() ==
>>>>                      FileTimeT::duration::min(),
>>>> -                "");
>>>> +                "value doesn't roundtrip");
>>>> +
>>>> +  static constexpr bool check_range() {
>>>> +    // This kinda sucks, but it's what happens when we don't have
>>>> __int128_t.
>>>> +    if (sizeof(TimeT) == sizeof(rep)) {
>>>> +      typedef duration<long long, ratio<3600 * 24 * 365> > Years;
>>>> +      return duration_cast<Years>(fs_seconds(max_seconds)) >
>>>> Years(250) &&
>>>> +             duration_cast<Years>(fs_seconds(min_seconds)) <
>>>> Years(-250);
>>>> +    }
>>>> +    return max_seconds >= numeric_limits<TimeT>::max() &&
>>>> +           min_seconds <= numeric_limits<TimeT>::min();
>>>> +  }
>>>> +  static_assert(check_range(), "the representable range is
>>>> unacceptable small");
>>>> +#endif
>>>>  };
>>>>
>>>> -template <class FileTimeT>
>>>> -struct fs_time_util_base<FileTimeT, true> {
>>>> -  static const long long max_seconds;
>>>> -  static const long long max_nsec;
>>>> -  static const long long min_seconds;
>>>> -  static const long long min_nsec_timespec;
>>>> +template <class FileTimeT, class TimeT>
>>>> +struct time_util_base<FileTimeT, TimeT, true> {
>>>> +  using rep = typename FileTimeT::rep;
>>>> +  using fs_duration = typename FileTimeT::duration;
>>>> +  using fs_seconds = duration<rep>;
>>>> +  using fs_nanoseconds = duration<rep, nano>;
>>>> +  using fs_microseconds = duration<rep, micro>;
>>>> +
>>>> +  static const rep max_seconds;
>>>> +  static const rep max_nsec;
>>>> +  static const rep min_seconds;
>>>> +  static const rep min_nsec_timespec;
>>>>  };
>>>>
>>>> -template <class FileTimeT>
>>>> -const long long fs_time_util_base<FileTimeT, true>::max_seconds =
>>>> -    duration_cast<seconds>(FileTimeT::duration::max()).count();
>>>> -
>>>> -template <class FileTimeT>
>>>> -const long long fs_time_util_base<FileTimeT, true>::max_nsec =
>>>> -    duration_cast<nanoseconds>(FileTimeT::duration::max() -
>>>> -                               seconds(max_seconds))
>>>> +template <class FileTimeT, class TimeT>
>>>> +const typename FileTimeT::rep
>>>> +    time_util_base<FileTimeT, TimeT, true>::max_seconds =
>>>> +        duration_cast<fs_seconds>(FileTimeT::duration::max()).count();
>>>> +
>>>> +template <class FileTimeT, class TimeT>
>>>> +const typename FileTimeT::rep time_util_base<FileTimeT, TimeT,
>>>> true>::max_nsec =
>>>> +    duration_cast<fs_nanoseconds>(FileTimeT::duration::max() -
>>>> +                                  fs_seconds(max_seconds))
>>>>          .count();
>>>>
>>>> -template <class FileTimeT>
>>>> -const long long fs_time_util_base<FileTimeT, true>::min_seconds =
>>>> -    duration_cast<seconds>(FileTimeT::duration::min()).count();
>>>> -
>>>> -template <class FileTimeT>
>>>> -const long long fs_time_util_base<FileTimeT, true>::min_nsec_timespec =
>>>> -    duration_cast<nanoseconds>(
>>>> -        (FileTimeT::duration::min() - seconds(min_seconds)) +
>>>> seconds(1))
>>>> -        .count();
>>>> +template <class FileTimeT, class TimeT>
>>>> +const typename FileTimeT::rep
>>>> +    time_util_base<FileTimeT, TimeT, true>::min_seconds =
>>>> +        duration_cast<fs_seconds>(FileTimeT::duration::min()).count();
>>>> +
>>>> +template <class FileTimeT, class TimeT>
>>>> +const typename FileTimeT::rep
>>>> +    time_util_base<FileTimeT, TimeT, true>::min_nsec_timespec =
>>>> +        duration_cast<fs_nanoseconds>((FileTimeT::duration::min() -
>>>> +                                       fs_seconds(min_seconds)) +
>>>> +                                      fs_seconds(1))
>>>> +            .count();
>>>>
>>>>  template <class FileTimeT, class TimeT, class TimeSpecT>
>>>> -struct fs_time_util : fs_time_util_base<FileTimeT> {
>>>> -  using Base = fs_time_util_base<FileTimeT>;
>>>> +struct time_util : time_util_base<FileTimeT, TimeT> {
>>>> +  using Base = time_util_base<FileTimeT, TimeT>;
>>>>    using Base::max_nsec;
>>>>    using Base::max_seconds;
>>>>    using Base::min_nsec_timespec;
>>>>    using Base::min_seconds;
>>>>
>>>> +  using typename Base::fs_duration;
>>>> +  using typename Base::fs_microseconds;
>>>> +  using typename Base::fs_nanoseconds;
>>>> +  using typename Base::fs_seconds;
>>>> +
>>>>  public:
>>>>    template <class CType, class ChronoType>
>>>> -  static bool checked_set(CType* out, ChronoType time) {
>>>> +  static _LIBCPP_CONSTEXPR_AFTER_CXX11 bool checked_set(CType* out,
>>>> +                                                        ChronoType
>>>> time) {
>>>>      using Lim = numeric_limits<CType>;
>>>>      if (time > Lim::max() || time < Lim::min())
>>>>        return false;
>>>> @@ -291,21 +318,21 @@ public:
>>>>
>>>>    static _LIBCPP_CONSTEXPR_AFTER_CXX11 bool is_representable(TimeSpecT
>>>> tm) {
>>>>      if (tm.tv_sec >= 0) {
>>>> -      return (tm.tv_sec < max_seconds) ||
>>>> +      return tm.tv_sec < max_seconds ||
>>>>               (tm.tv_sec == max_seconds && tm.tv_nsec <= max_nsec);
>>>>      } else if (tm.tv_sec == (min_seconds - 1)) {
>>>>        return tm.tv_nsec >= min_nsec_timespec;
>>>>      } else {
>>>> -      return (tm.tv_sec >= min_seconds);
>>>> +      return tm.tv_sec >= min_seconds;
>>>>      }
>>>>    }
>>>>
>>>>    static _LIBCPP_CONSTEXPR_AFTER_CXX11 bool is_representable(FileTimeT
>>>> tm) {
>>>> -    auto secs = duration_cast<seconds>(tm.time_since_epoch());
>>>> -    auto nsecs = duration_cast<nanoseconds>(tm.time_since_epoch() -
>>>> secs);
>>>> +    auto secs = duration_cast<fs_seconds>(tm.time_since_epoch());
>>>> +    auto nsecs = duration_cast<fs_nanoseconds>(tm.time_since_epoch() -
>>>> secs);
>>>>      if (nsecs.count() < 0) {
>>>> -      secs = secs + seconds(1);
>>>> -      nsecs = nsecs + seconds(1);
>>>> +      secs = secs + fs_seconds(1);
>>>> +      nsecs = nsecs + fs_seconds(1);
>>>>      }
>>>>      using TLim = numeric_limits<TimeT>;
>>>>      if (secs.count() >= 0)
>>>> @@ -314,49 +341,45 @@ public:
>>>>    }
>>>>
>>>>    static _LIBCPP_CONSTEXPR_AFTER_CXX11 FileTimeT
>>>> -  convert_timespec(TimeSpecT tm) {
>>>> -    auto adj_msec =
>>>> duration_cast<microseconds>(nanoseconds(tm.tv_nsec));
>>>> -    if (tm.tv_sec >= 0) {
>>>> -      auto Dur = seconds(tm.tv_sec) + microseconds(adj_msec);
>>>> -      return FileTimeT(Dur);
>>>> -    } else if
>>>> (duration_cast<microseconds>(nanoseconds(tm.tv_nsec)).count() ==
>>>> -               0) {
>>>> -      return FileTimeT(seconds(tm.tv_sec));
>>>> +  convert_from_timespec(TimeSpecT tm) {
>>>> +    if (tm.tv_sec >= 0 || tm.tv_nsec == 0) {
>>>> +      return FileTimeT(fs_seconds(tm.tv_sec) +
>>>> +
>>>>  duration_cast<fs_duration>(fs_nanoseconds(tm.tv_nsec)));
>>>>      } else { // tm.tv_sec < 0
>>>> -      auto adj_subsec =
>>>> -          duration_cast<microseconds>(seconds(1) -
>>>> nanoseconds(tm.tv_nsec));
>>>> -      auto Dur = seconds(tm.tv_sec + 1) - adj_subsec;
>>>> +      auto adj_subsec = duration_cast<fs_duration>(fs_seconds(1) -
>>>> +
>>>>  fs_nanoseconds(tm.tv_nsec));
>>>> +      auto Dur = fs_seconds(tm.tv_sec + 1) - adj_subsec;
>>>>        return FileTimeT(Dur);
>>>>      }
>>>>    }
>>>>
>>>> -  template <class SubSecDurT, class SubSecT>
>>>> -  static bool set_times_checked(TimeT* sec_out, SubSecT* subsec_out,
>>>> -                                FileTimeT tp) {
>>>> +  template <class SubSecT>
>>>> +  static _LIBCPP_CONSTEXPR_AFTER_CXX11 bool
>>>> +  set_times_checked(TimeT* sec_out, SubSecT* subsec_out, FileTimeT tp)
>>>> {
>>>>      auto dur = tp.time_since_epoch();
>>>> -    auto sec_dur = duration_cast<seconds>(dur);
>>>> -    auto subsec_dur = duration_cast<SubSecDurT>(dur - sec_dur);
>>>> +    auto sec_dur = duration_cast<fs_seconds>(dur);
>>>> +    auto subsec_dur = duration_cast<fs_nanoseconds>(dur - sec_dur);
>>>>      // The tv_nsec and tv_usec fields must not be negative so adjust
>>>> accordingly
>>>>      if (subsec_dur.count() < 0) {
>>>>        if (sec_dur.count() > min_seconds) {
>>>> -        sec_dur -= seconds(1);
>>>> -        subsec_dur += seconds(1);
>>>> +        sec_dur -= fs_seconds(1);
>>>> +        subsec_dur += fs_seconds(1);
>>>>        } else {
>>>> -        subsec_dur = SubSecDurT::zero();
>>>> +        subsec_dur = fs_nanoseconds::zero();
>>>>        }
>>>>      }
>>>>      return checked_set(sec_out, sec_dur.count()) &&
>>>>             checked_set(subsec_out, subsec_dur.count());
>>>>    }
>>>> +  static _LIBCPP_CONSTEXPR_AFTER_CXX11 bool
>>>> convert_to_timespec(TimeSpecT& dest,
>>>> +
>>>> FileTimeT tp) {
>>>> +    if (!is_representable(tp))
>>>> +      return false;
>>>> +    return set_times_checked(&dest.tv_sec, &dest.tv_nsec, tp);
>>>> +  }
>>>>  };
>>>>
>>>> -} // namespace time_util
>>>> -
>>>> -
>>>> -using TimeSpec = struct ::timespec;
>>>> -using StatT = struct ::stat;
>>>> -
>>>> -using FSTime = time_util::fs_time_util<file_time_type, time_t, struct
>>>> timespec>;
>>>> +using fs_time = time_util<file_time_type, time_t, TimeSpec>;
>>>>
>>>>  #if defined(__APPLE__)
>>>>  TimeSpec extract_mtime(StatT const& st) { return st.st_mtimespec; }
>>>> @@ -366,20 +389,18 @@ TimeSpec extract_mtime(StatT const& st)
>>>>  TimeSpec extract_atime(StatT const& st) { return st.st_atim; }
>>>>  #endif
>>>>
>>>> -#if !defined(_LIBCXX_USE_UTIMENSAT)
>>>> -using TimeStruct = struct ::timeval;
>>>> -using TimeStructArray = TimeStruct[2];
>>>> -#else
>>>> -using TimeStruct = TimeSpec;
>>>> -using TimeStructArray = TimeStruct[2];
>>>> -#endif
>>>> -
>>>> -bool SetFileTimes(const path& p, TimeStructArray const& TS,
>>>> -                  error_code& ec) {
>>>> -#if !defined(_LIBCXX_USE_UTIMENSAT)
>>>> -  if (::utimes(p.c_str(), TS) == -1)
>>>> +bool set_file_times(const path& p, std::array<TimeSpec, 2> const& TS,
>>>> +                    error_code& ec) {
>>>> +#if !defined(_LIBCPP_USE_UTIMENSAT)
>>>> +  using namespace chrono;
>>>> +  auto Convert = [](long nsec) {
>>>> +    return duration_cast<microseconds>(nanoseconds(nsec)).count();
>>>> +  };
>>>> +  struct ::timeval ConvertedTS[2] = {{TS[0].tv_sec,
>>>> Convert(TS[0].tv_nsec)},
>>>> +                                     {TS[1].tv_sec,
>>>> Convert(TS[1].tv_nsec)}};
>>>>
>>>
>>> This causes the '-Wc++11-narrowing' warning on Darwin:
>>>
>>> filesystem_common.h:399:53: error: non-constant-expression cannot be
>>> narrowed from type 'long long' to '__darwin_suseconds_t' (aka 'int') in
>>> initializer list [-Wc++11-narrowing] struct ::timeval ConvertedTS[2] =
>>> {{TS[0].tv_sec, Convert(TS[0].tv_nsec)}, ^~~~~~~~~~~~~~~~~~~~~~
>>> I'll work on a fix commit.
>>>
>>>
>>>> +  if (::utimes(p.c_str(), ConvertedTS) == -1)
>>>>  #else
>>>> -  if (::utimensat(AT_FDCWD, p.c_str(), TS, 0) == -1)
>>>> +  if (::utimensat(AT_FDCWD, p.c_str(), TS.data(), 0) == -1)
>>>>  #endif
>>>>    {
>>>>      ec = capture_errno();
>>>> @@ -388,25 +409,9 @@ bool SetFileTimes(const path& p, TimeStr
>>>>    return false;
>>>>  }
>>>>
>>>> -void SetTimeStructTo(TimeStruct& TS, TimeSpec ToTS) {
>>>> -  using namespace chrono;
>>>> -  TS.tv_sec = ToTS.tv_sec;
>>>> -#if !defined(_LIBCXX_USE_UTIMENSAT)
>>>> -  TS.tv_usec =
>>>> duration_cast<microseconds>(nanoseconds(ToTS.tv_nsec)).count();
>>>> -#else
>>>> -  TS.tv_nsec = ToTS.tv_nsec;
>>>> -#endif
>>>> -}
>>>> -
>>>> -bool SetTimeStructTo(TimeStruct& TS, file_time_type NewTime) {
>>>> -  using namespace chrono;
>>>> -#if !defined(_LIBCXX_USE_UTIMENSAT)
>>>> -  return !FSTime::set_times_checked<microseconds>(&TS.tv_sec,
>>>> &TS.tv_usec,
>>>> -                                                  NewTime);
>>>> -#else
>>>> -  return !FSTime::set_times_checked<nanoseconds>(&TS.tv_sec,
>>>> &TS.tv_nsec,
>>>> -                                                 NewTime);
>>>> -#endif
>>>> +bool set_time_spec_to(TimeSpec& TS, file_time_type NewTime) {
>>>> +  return !fs_time::set_times_checked(
>>>> +      &TS.tv_sec, &TS.tv_nsec, NewTime);
>>>>  }
>>>>
>>>>  } // namespace
>>>>
>>>> Modified: libcxx/trunk/src/experimental/filesystem/operations.cpp
>>>> URL:
>>>> http://llvm.org/viewvc/llvm-project/libcxx/trunk/src/experimental/filesystem/operations.cpp?rev=337960&r1=337959&r2=337960&view=diff
>>>>
>>>> ==============================================================================
>>>> --- libcxx/trunk/src/experimental/filesystem/operations.cpp (original)
>>>> +++ libcxx/trunk/src/experimental/filesystem/operations.cpp Wed Jul 25
>>>> 13:51:49 2018
>>>> @@ -23,6 +23,7 @@
>>>>  #include <unistd.h>
>>>>  #include <sys/stat.h>
>>>>  #include <sys/statvfs.h>
>>>> +#include <time.h>
>>>>  #include <fcntl.h>  /* values for fchmodat */
>>>>
>>>>  #if defined(__linux__)
>>>> @@ -36,6 +37,14 @@
>>>>  # define _LIBCPP_USE_COPYFILE
>>>>  #endif
>>>>
>>>> +#if !defined(__APPLE__)
>>>> +#define _LIBCPP_USE_CLOCK_GETTIME
>>>> +#endif
>>>> +
>>>> +#if !defined(CLOCK_REALTIME) || !defined(_LIBCPP_USE_CLOCK_GETTIME)
>>>> +#include <sys/time.h> // for gettimeofday and timeval
>>>> +#endif                // !defined(CLOCK_REALTIME)
>>>> +
>>>>  #if defined(_LIBCPP_COMPILER_GCC)
>>>>  #if _GNUC_VER < 500
>>>>  #pragma GCC diagnostic ignored "-Wmissing-field-initializers"
>>>> @@ -44,9 +53,6 @@
>>>>
>>>>  _LIBCPP_BEGIN_NAMESPACE_EXPERIMENTAL_FILESYSTEM
>>>>
>>>> -filesystem_error::~filesystem_error() {}
>>>> -
>>>> -
>>>>  namespace { namespace parser
>>>>  {
>>>>
>>>> @@ -355,7 +361,7 @@ private:
>>>>    explicit FileDescriptor(const path* p, int fd = -1) : name(*p),
>>>> fd(fd) {}
>>>>  };
>>>>
>>>> -perms posix_get_perms(const struct ::stat& st) noexcept {
>>>> +perms posix_get_perms(const StatT& st) noexcept {
>>>>    return static_cast<perms>(st.st_mode) & perms::mask;
>>>>  }
>>>>
>>>> @@ -364,8 +370,7 @@ perms posix_get_perms(const struct ::sta
>>>>  }
>>>>
>>>>  file_status create_file_status(error_code& m_ec, path const& p,
>>>> -                               const struct ::stat& path_stat,
>>>> -                               error_code* ec) {
>>>> +                               const StatT& path_stat, error_code* ec)
>>>> {
>>>>    if (ec)
>>>>      *ec = m_ec;
>>>>    if (m_ec && (m_ec.value() == ENOENT || m_ec.value() == ENOTDIR)) {
>>>> @@ -400,8 +405,7 @@ file_status create_file_status(error_cod
>>>>    return fs_tmp;
>>>>  }
>>>>
>>>> -file_status posix_stat(path const& p, struct ::stat& path_stat,
>>>> -                       error_code* ec) {
>>>> +file_status posix_stat(path const& p, StatT& path_stat, error_code*
>>>> ec) {
>>>>    error_code m_ec;
>>>>    if (::stat(p.c_str(), &path_stat) == -1)
>>>>      m_ec = detail::capture_errno();
>>>> @@ -409,12 +413,11 @@ file_status posix_stat(path const& p, st
>>>>  }
>>>>
>>>>  file_status posix_stat(path const& p, error_code* ec) {
>>>> -  struct ::stat path_stat;
>>>> +  StatT path_stat;
>>>>    return posix_stat(p, path_stat, ec);
>>>>  }
>>>>
>>>> -file_status posix_lstat(path const& p, struct ::stat& path_stat,
>>>> -                        error_code* ec) {
>>>> +file_status posix_lstat(path const& p, StatT& path_stat, error_code*
>>>> ec) {
>>>>    error_code m_ec;
>>>>    if (::lstat(p.c_str(), &path_stat) == -1)
>>>>      m_ec = detail::capture_errno();
>>>> @@ -422,7 +425,7 @@ file_status posix_lstat(path const& p, s
>>>>  }
>>>>
>>>>  file_status posix_lstat(path const& p, error_code* ec) {
>>>> -  struct ::stat path_stat;
>>>> +  StatT path_stat;
>>>>    return posix_lstat(p, path_stat, ec);
>>>>  }
>>>>
>>>> @@ -464,10 +467,32 @@ file_status FileDescriptor::refresh_stat
>>>>  using detail::capture_errno;
>>>>  using detail::ErrorHandler;
>>>>  using detail::StatT;
>>>> +using detail::TimeSpec;
>>>>  using parser::createView;
>>>>  using parser::PathParser;
>>>>  using parser::string_view_t;
>>>>
>>>> +const bool _FilesystemClock::is_steady;
>>>> +
>>>> +_FilesystemClock::time_point _FilesystemClock::now() noexcept {
>>>> +  typedef chrono::duration<rep> __secs;
>>>> +#if defined(_LIBCPP_USE_CLOCK_GETTIME) && defined(CLOCK_REALTIME)
>>>> +  typedef chrono::duration<rep, nano> __nsecs;
>>>> +  struct timespec tp;
>>>> +  if (0 != clock_gettime(CLOCK_REALTIME, &tp))
>>>> +    __throw_system_error(errno, "clock_gettime(CLOCK_REALTIME)
>>>> failed");
>>>> +  return time_point(__secs(tp.tv_sec) +
>>>> +
>>>> chrono::duration_cast<duration>(__nsecs(tp.tv_nsec)));
>>>> +#else
>>>> +  typedef chrono::duration<rep, micro> __microsecs;
>>>> +  timeval tv;
>>>> +  gettimeofday(&tv, 0);
>>>> +  return time_point(__secs(tv.tv_sec) + __microsecs(tv.tv_usec));
>>>> +#endif // _LIBCPP_USE_CLOCK_GETTIME && CLOCK_REALTIME
>>>> +}
>>>> +
>>>> +filesystem_error::~filesystem_error() {}
>>>> +
>>>>  void filesystem_error::__create_what(int __num_paths) {
>>>>    const char* derived_what = system_error::what();
>>>>    __storage_->__what_ = [&]() -> string {
>>>> @@ -525,14 +550,14 @@ void __copy(const path& from, const path
>>>>    const bool sym_status2 = bool(options & copy_options::copy_symlinks);
>>>>
>>>>    error_code m_ec1;
>>>> -  struct ::stat f_st = {};
>>>> +  StatT f_st = {};
>>>>    const file_status f = sym_status || sym_status2
>>>>                              ? detail::posix_lstat(from, f_st, &m_ec1)
>>>>                              : detail::posix_stat(from, f_st, &m_ec1);
>>>>    if (m_ec1)
>>>>      return err.report(m_ec1);
>>>>
>>>> -  struct ::stat t_st = {};
>>>> +  StatT t_st = {};
>>>>    const file_status t = sym_status ? detail::posix_lstat(to, t_st,
>>>> &m_ec1)
>>>>                                     : detail::posix_stat(to, t_st,
>>>> &m_ec1);
>>>>
>>>> @@ -916,7 +941,7 @@ uintmax_t __file_size(const path& p, err
>>>>    ErrorHandler<uintmax_t> err("file_size", ec, &p);
>>>>
>>>>    error_code m_ec;
>>>> -  struct ::stat st;
>>>> +  StatT st;
>>>>    file_status fst = detail::posix_stat(p, st, &m_ec);
>>>>    if (!exists(fst) || !is_regular_file(fst)) {
>>>>      errc error_kind =
>>>> @@ -966,14 +991,14 @@ bool __fs_is_empty(const path& p, error_
>>>>
>>>>  static file_time_type __extract_last_write_time(const path& p, const
>>>> StatT& st,
>>>>                                                  error_code* ec) {
>>>> -  using detail::FSTime;
>>>> +  using detail::fs_time;
>>>>    ErrorHandler<file_time_type> err("last_write_time", ec, &p);
>>>>
>>>>    auto ts = detail::extract_mtime(st);
>>>> -  if (!FSTime::is_representable(ts))
>>>> +  if (!fs_time::is_representable(ts))
>>>>      return err.report(errc::value_too_large);
>>>>
>>>> -  return FSTime::convert_timespec(ts);
>>>> +  return fs_time::convert_from_timespec(ts);
>>>>  }
>>>>
>>>>  file_time_type __last_write_time(const path& p, error_code *ec)
>>>> @@ -992,30 +1017,27 @@ file_time_type __last_write_time(const p
>>>>  void __last_write_time(const path& p, file_time_type new_time,
>>>>                         error_code *ec)
>>>>  {
>>>> -    using namespace chrono;
>>>> -    using namespace detail;
>>>> -
>>>>      ErrorHandler<void> err("last_write_time", ec, &p);
>>>>
>>>>      error_code m_ec;
>>>> -    TimeStructArray tbuf;
>>>> -#if !defined(_LIBCXX_USE_UTIMENSAT)
>>>> +    array<TimeSpec, 2> tbuf;
>>>> +#if !defined(_LIBCPP_USE_UTIMENSAT)
>>>>      // This implementation has a race condition between determining the
>>>>      // last access time and attempting to set it to the same value
>>>> using
>>>>      // ::utimes
>>>> -    struct ::stat st;
>>>> +    StatT st;
>>>>      file_status fst = detail::posix_stat(p, st, &m_ec);
>>>> -    if (m_ec && !status_known(fst))
>>>> +    if (m_ec)
>>>>        return err.report(m_ec);
>>>> -    SetTimeStructTo(tbuf[0], detail::extract_atime(st));
>>>> +    tbuf[0] = detail::extract_atime(st);
>>>>  #else
>>>>      tbuf[0].tv_sec = 0;
>>>>      tbuf[0].tv_nsec = UTIME_OMIT;
>>>>  #endif
>>>> -    if (SetTimeStructTo(tbuf[1], new_time))
>>>> -      return err.report(errc::invalid_argument);
>>>> +    if (detail::set_time_spec_to(tbuf[1], new_time))
>>>> +      return err.report(errc::value_too_large);
>>>>
>>>> -    SetFileTimes(p, tbuf, m_ec);
>>>> +    detail::set_file_times(p, tbuf, m_ec);
>>>>      if (m_ec)
>>>>        return err.report(m_ec);
>>>>  }
>>>> @@ -1591,7 +1613,7 @@ error_code directory_entry::__do_refresh
>>>>    __data_.__reset();
>>>>    error_code failure_ec;
>>>>
>>>> -  struct ::stat full_st;
>>>> +  StatT full_st;
>>>>    file_status st = detail::posix_lstat(__p_, full_st, &failure_ec);
>>>>    if (!status_known(st)) {
>>>>      __data_.__reset();
>>>>
>>>> Added: libcxx/trunk/src/include/apple_availability.h
>>>> URL:
>>>> http://llvm.org/viewvc/llvm-project/libcxx/trunk/src/include/apple_availability.h?rev=337960&view=auto
>>>>
>>>> ==============================================================================
>>>> --- libcxx/trunk/src/include/apple_availability.h (added)
>>>> +++ libcxx/trunk/src/include/apple_availability.h Wed Jul 25 13:51:49
>>>> 2018
>>>> @@ -0,0 +1,52 @@
>>>> +//===------------------------ apple_availability.h
>>>> ------------------------===//
>>>> +//
>>>> +//                     The LLVM Compiler Infrastructure
>>>> +//
>>>> +// This file is dual licensed under the MIT and the University of
>>>> Illinois Open
>>>> +// Source Licenses. See LICENSE.TXT for details.
>>>> +//
>>>>
>>>> +//===----------------------------------------------------------------------===//
>>>> +#ifndef _LIBCPP_SRC_INCLUDE_APPLE_AVAILABILITY_H
>>>> +#define _LIBCPP_SRC_INCLUDE_APPLE_AVAILABILITY_H
>>>> +
>>>> +#if defined(__APPLE__)
>>>> +
>>>> +#if defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__)
>>>> +#if __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ >= 101300
>>>> +#define _LIBCPP_USE_UTIMENSAT
>>>> +#endif
>>>> +#elif defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__)
>>>> +#if __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ >= 110000
>>>> +#define _LIBCPP_USE_UTIMENSAT
>>>> +#endif
>>>> +#elif defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__)
>>>> +#if __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ >= 110000
>>>> +#define _LIBCPP_USE_UTIMENSAT
>>>> +#endif
>>>> +#elif defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__)
>>>> +#if __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ >= 40000
>>>> +#define _LIBCPP_USE_UTIMENSAT
>>>> +#endif
>>>> +#endif // __ENVIRONMENT_.*_VERSION_MIN_REQUIRED__
>>>> +
>>>> +#if defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__)
>>>> +#if __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ >= 101200
>>>> +#define _LIBCPP_USE_CLOCK_GETTIME
>>>> +#endif
>>>> +#elif defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__)
>>>> +#if __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ >= 100000
>>>> +#define _LIBCPP_USE_CLOCK_GETTIME
>>>> +#endif
>>>> +#elif defined(__ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__)
>>>> +#if __ENVIRONMENT_TV_OS_VERSION_MIN_REQUIRED__ >= 100000
>>>> +#define _LIBCPP_USE_CLOCK_GETTIME
>>>> +#endif
>>>> +#elif defined(__ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__)
>>>> +#if __ENVIRONMENT_WATCH_OS_VERSION_MIN_REQUIRED__ >= 30000
>>>> +#define _LIBCPP_USE_CLOCK_GETTIME
>>>> +#endif
>>>> +#endif // __ENVIRONMENT_.*_VERSION_MIN_REQUIRED__
>>>> +
>>>> +#endif // __APPLE__
>>>> +
>>>> +#endif // _LIBCPP_SRC_INCLUDE_APPLE_AVAILABILITY_H
>>>>
>>>> Modified:
>>>> libcxx/trunk/test/libcxx/experimental/filesystem/class.directory_entry/directory_entry.mods/last_write_time.sh.cpp
>>>> URL:
>>>> http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/libcxx/experimental/filesystem/class.directory_entry/directory_entry.mods/last_write_time.sh.cpp?rev=337960&r1=337959&r2=337960&view=diff
>>>>
>>>> ==============================================================================
>>>> ---
>>>> libcxx/trunk/test/libcxx/experimental/filesystem/class.directory_entry/directory_entry.mods/last_write_time.sh.cpp
>>>> (original)
>>>> +++
>>>> libcxx/trunk/test/libcxx/experimental/filesystem/class.directory_entry/directory_entry.mods/last_write_time.sh.cpp
>>>> Wed Jul 25 13:51:49 2018
>>>> @@ -41,9 +41,7 @@ TEST_CASE(last_write_time_not_representa
>>>>    ToTime.tv_sec = std::numeric_limits<decltype(ToTime.tv_sec)>::max();
>>>>    ToTime.tv_nsec = duration_cast<nanoseconds>(seconds(1)).count() - 1;
>>>>
>>>> -  TimeStructArray TS;
>>>> -  SetTimeStructTo(TS[0], ToTime);
>>>> -  SetTimeStructTo(TS[1], ToTime);
>>>> +  std::array<TimeSpec, 2> TS = {ToTime, ToTime};
>>>>
>>>>    file_time_type old_time = last_write_time(file);
>>>>    directory_entry ent(file);
>>>> @@ -57,9 +55,7 @@ TEST_CASE(last_write_time_not_representa
>>>>    file_time_type rep_value;
>>>>    {
>>>>      std::error_code ec;
>>>> -    if (SetFileTimes(file, TS, ec)) {
>>>> -      TEST_REQUIRE(false && "unsupported");
>>>> -    }
>>>> +    TEST_REQUIRE(!set_file_times(file, TS, ec));
>>>>      ec.clear();
>>>>      rep_value = last_write_time(file, ec);
>>>>      IsRepresentable = !bool(ec);
>>>> @@ -82,7 +78,7 @@ TEST_CASE(last_write_time_not_representa
>>>>
>>>>      ExceptionChecker CheckExcept(file, expected_err,
>>>>                                   "directory_entry::last_write_time");
>>>> -    TEST_CHECK_THROW_RESULT(fs::filesystem_error, CheckExcept,
>>>> +    TEST_CHECK_THROW_RESULT(filesystem_error, CheckExcept,
>>>>                              ent.last_write_time());
>>>>
>>>>    } else {
>>>>
>>>> Modified:
>>>> libcxx/trunk/test/libcxx/experimental/filesystem/convert_file_time.sh.cpp
>>>> URL:
>>>> http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/libcxx/experimental/filesystem/convert_file_time.sh.cpp?rev=337960&r1=337959&r2=337960&view=diff
>>>>
>>>> ==============================================================================
>>>> ---
>>>> libcxx/trunk/test/libcxx/experimental/filesystem/convert_file_time.sh.cpp
>>>> (original)
>>>> +++
>>>> libcxx/trunk/test/libcxx/experimental/filesystem/convert_file_time.sh.cpp
>>>> Wed Jul 25 13:51:49 2018
>>>> @@ -25,15 +25,23 @@
>>>>
>>>>  #include "filesystem_common.h"
>>>>
>>>> +#ifndef __SIZEOF_INT128__
>>>> +#define TEST_HAS_NO_INT128_T
>>>> +#endif
>>>> +
>>>>  using namespace std::chrono;
>>>>  namespace fs = std::experimental::filesystem;
>>>>  using fs::file_time_type;
>>>> -using fs::detail::time_util::fs_time_util;
>>>> +using fs::detail::time_util;
>>>> +
>>>> +#ifdef TEST_HAS_NO_INT128_T
>>>> +static_assert(sizeof(fs::file_time_type::rep) <= 8, "");
>>>> +#endif
>>>>
>>>> -enum TestKind { TK_64Bit, TK_32Bit, TK_FloatingPoint };
>>>> +enum TestKind { TK_128Bit, TK_64Bit, TK_32Bit, TK_FloatingPoint };
>>>>
>>>> -template <class FileTimeT, class TimeT, class TimeSpec>
>>>> -constexpr TestKind getTestKind() {
>>>> +template <class TimeT>
>>>> +constexpr TestKind getTimeTTestKind() {
>>>>    if (sizeof(TimeT) == 8 && !std::is_floating_point<TimeT>::value)
>>>>      return TK_64Bit;
>>>>    else if (sizeof(TimeT) == 4 && !std::is_floating_point<TimeT>::value)
>>>> @@ -43,17 +51,99 @@ constexpr TestKind getTestKind() {
>>>>    else
>>>>      assert(false && "test kind not supported");
>>>>  }
>>>> +template <class FileTimeT>
>>>> +constexpr TestKind getFileTimeTestKind() {
>>>> +  using Rep = typename FileTimeT::rep;
>>>> +  if (std::is_floating_point<Rep>::value)
>>>> +    return TK_FloatingPoint;
>>>> +  if (sizeof(Rep) == 16)
>>>> +    return TK_128Bit;
>>>> +  if (sizeof(Rep) == 8)
>>>> +    return TK_64Bit;
>>>> +  assert(false && "test kind not supported");
>>>> +}
>>>>
>>>>  template <class FileTimeT, class TimeT, class TimeSpecT,
>>>> -          class Base = fs_time_util<FileTimeT, TimeT, TimeSpecT>,
>>>> -          TestKind = getTestKind<FileTimeT, TimeT, TimeSpecT>()>
>>>> -struct check_is_representable;
>>>> +          class Base = time_util<FileTimeT, TimeT, TimeSpecT>,
>>>> +          TestKind = getTimeTTestKind<TimeT>(),
>>>> +          TestKind = getFileTimeTestKind<FileTimeT>()>
>>>> +struct test_case;
>>>>
>>>>  template <class FileTimeT, class TimeT, class TimeSpecT, class Base>
>>>> -struct check_is_representable<FileTimeT, TimeT, TimeSpecT, Base,
>>>> TK_64Bit>
>>>> +struct test_case<FileTimeT, TimeT, TimeSpecT, Base, TK_64Bit,
>>>> TK_128Bit>
>>>>      : public Base {
>>>>
>>>> -  using Base::convert_timespec;
>>>> +  using Base::convert_from_timespec;
>>>> +  using Base::convert_to_timespec;
>>>> +  using Base::is_representable;
>>>> +  using Base::max_nsec;
>>>> +  using Base::max_seconds;
>>>> +  using Base::min_nsec_timespec;
>>>> +  using Base::min_seconds;
>>>> +
>>>> +  static constexpr auto max_time_t = std::numeric_limits<TimeT>::max();
>>>> +  static constexpr auto min_time_t = std::numeric_limits<TimeT>::min();
>>>> +
>>>> +  static constexpr bool test_timespec() {
>>>> +    static_assert(is_representable(TimeSpecT{max_time_t, 0}), "");
>>>> +    static_assert(is_representable(TimeSpecT{max_time_t, 999999999}),
>>>> "");
>>>> +    static_assert(is_representable(TimeSpecT{max_time_t, 1000000000}),
>>>> "");
>>>> +    static_assert(is_representable(TimeSpecT{max_time_t, max_nsec}),
>>>> "");
>>>> +
>>>> +    static_assert(is_representable(TimeSpecT{min_time_t, 0}), "");
>>>> +    static_assert(is_representable(TimeSpecT{min_time_t, 999999999}),
>>>> "");
>>>> +    static_assert(is_representable(TimeSpecT{min_time_t, 1000000000}),
>>>> "");
>>>> +    static_assert(is_representable(TimeSpecT{min_time_t,
>>>> min_nsec_timespec}),
>>>> +                  "");
>>>> +
>>>> +    return true;
>>>> +  }
>>>> +
>>>> +  static constexpr bool test_file_time_type() {
>>>> +    // This kinda sucks. Oh well.
>>>> +    static_assert(!Base::is_representable(FileTimeT::max()), "");
>>>> +    static_assert(!Base::is_representable(FileTimeT::min()), "");
>>>> +    return true;
>>>> +  }
>>>> +
>>>> +  static constexpr bool check_round_trip(TimeSpecT orig) {
>>>> +    TimeSpecT new_ts = {};
>>>> +    FileTimeT out = convert_from_timespec(orig);
>>>> +    assert(convert_to_timespec(new_ts, out));
>>>> +    return new_ts.tv_sec == orig.tv_sec && new_ts.tv_nsec ==
>>>> orig.tv_nsec;
>>>> +  }
>>>> +
>>>> +  static constexpr bool test_convert_timespec() {
>>>> +    static_assert(check_round_trip({0, 0}), "");
>>>> +    static_assert(check_round_trip({0, 1}), "");
>>>> +    static_assert(check_round_trip({1, 1}), "");
>>>> +    static_assert(check_round_trip({-1, 1}), "");
>>>> +    static_assert(check_round_trip({max_time_t, max_nsec}), "");
>>>> +    static_assert(check_round_trip({max_time_t, 123}), "");
>>>> +    static_assert(check_round_trip({min_time_t, min_nsec_timespec}),
>>>> "");
>>>> +    static_assert(check_round_trip({min_time_t, 123}), "");
>>>> +    return true;
>>>> +  }
>>>> +
>>>> +  static bool test() {
>>>> +    static_assert(test_timespec(), "");
>>>> +    static_assert(test_file_time_type(), "");
>>>> +    static_assert(test_convert_timespec(), "");
>>>> +    return true;
>>>> +  }
>>>> +};
>>>> +
>>>> +template <class FileTimeT, class TimeT, class TimeSpecT, class Base>
>>>> +struct test_case<FileTimeT, TimeT, TimeSpecT, Base, TK_32Bit,
>>>> TK_128Bit>
>>>> +    : public test_case<FileTimeT, TimeT, TimeSpecT, Base, TK_64Bit,
>>>> TK_128Bit> {
>>>> +
>>>> +};
>>>> +
>>>> +template <class FileTimeT, class TimeT, class TimeSpecT, class Base>
>>>> +struct test_case<FileTimeT, TimeT, TimeSpecT, Base, TK_64Bit, TK_64Bit>
>>>> +    : public Base {
>>>> +
>>>> +  using Base::convert_from_timespec;
>>>>    using Base::is_representable;
>>>>    using Base::max_nsec;
>>>>    using Base::max_seconds;
>>>> @@ -88,24 +178,25 @@ struct check_is_representable<FileTimeT,
>>>>    }
>>>>
>>>>    static constexpr bool test_convert_timespec() {
>>>> -    static_assert(convert_timespec(TimeSpecT{max_seconds, max_nsec}) ==
>>>> +    static_assert(convert_from_timespec(TimeSpecT{max_seconds,
>>>> max_nsec}) ==
>>>>                        FileTimeT::max(),
>>>>                    "");
>>>> -    static_assert(convert_timespec(TimeSpecT{max_seconds, max_nsec -
>>>> 1}) <
>>>> +    static_assert(convert_from_timespec(TimeSpecT{max_seconds,
>>>> max_nsec - 1}) <
>>>>                        FileTimeT::max(),
>>>>                    "");
>>>> -    static_assert(convert_timespec(TimeSpecT{max_seconds - 1,
>>>> 999999999}) <
>>>> +    static_assert(convert_from_timespec(TimeSpecT{max_seconds - 1,
>>>> 999999999}) <
>>>>                        FileTimeT::max(),
>>>>                    "");
>>>> -    static_assert(convert_timespec(TimeSpecT{
>>>> +    static_assert(convert_from_timespec(TimeSpecT{
>>>>                        min_seconds - 1, min_nsec_timespec}) ==
>>>> FileTimeT::min(),
>>>>                    "");
>>>> -    static_assert(
>>>> -        convert_timespec(TimeSpecT{min_seconds - 1, min_nsec_timespec
>>>> + 1}) >
>>>> -            FileTimeT::min(),
>>>> -        "");
>>>> -    static_assert(
>>>> -        convert_timespec(TimeSpecT{min_seconds, 0}) >
>>>> FileTimeT::min(), "");
>>>> +    static_assert(convert_from_timespec(
>>>> +                      TimeSpecT{min_seconds - 1, min_nsec_timespec +
>>>> 1}) >
>>>> +                      FileTimeT::min(),
>>>> +                  "");
>>>> +    static_assert(convert_from_timespec(TimeSpecT{min_seconds, 0}) >
>>>> +                      FileTimeT::min(),
>>>> +                  "");
>>>>      return true;
>>>>    }
>>>>
>>>> @@ -118,12 +209,12 @@ struct check_is_representable<FileTimeT,
>>>>  };
>>>>
>>>>  template <class FileTimeT, class TimeT, class TimeSpecT, class Base>
>>>> -struct check_is_representable<FileTimeT, TimeT, TimeSpecT, Base,
>>>> TK_32Bit>
>>>> +struct test_case<FileTimeT, TimeT, TimeSpecT, Base, TK_32Bit, TK_64Bit>
>>>>      : public Base {
>>>>    static constexpr auto max_time_t = std::numeric_limits<TimeT>::max();
>>>>    static constexpr auto min_time_t = std::numeric_limits<TimeT>::min();
>>>>
>>>> -  using Base::convert_timespec;
>>>> +  using Base::convert_from_timespec;
>>>>    using Base::is_representable;
>>>>    using Base::max_nsec;
>>>>    using Base::max_seconds;
>>>> @@ -158,9 +249,10 @@ struct check_is_representable<FileTimeT,
>>>>    }
>>>>  };
>>>>
>>>> -template <class FileTimeT, class TimeT, class TimeSpec, class Base>
>>>> -struct check_is_representable<FileTimeT, TimeT, TimeSpec, Base,
>>>> -                              TK_FloatingPoint> : public Base {
>>>> +template <class FileTimeT, class TimeT, class TimeSpec, class Base,
>>>> +          TestKind FileTimeTKind>
>>>> +struct test_case<FileTimeT, TimeT, TimeSpec, Base, TK_FloatingPoint,
>>>> +                 FileTimeTKind> : public Base {
>>>>
>>>>    static bool test() { return true; }
>>>>  };
>>>> @@ -182,19 +274,33 @@ struct TestClock {
>>>>    static time_point now() noexcept { return {}; }
>>>>  };
>>>>
>>>> -template <class IntType, class Dur = duration<IntType, std::micro> >
>>>> -using TestFileTimeT = time_point<TestClock<Dur> >;
>>>> +template <class IntType, class Period = std::micro>
>>>> +using TestFileTimeT = time_point<TestClock<duration<IntType, Period> >
>>>> >;
>>>>
>>>>  int main() {
>>>> -  assert((
>>>> -      check_is_representable<file_time_type, time_t, struct
>>>> timespec>::test()));
>>>> -  assert((check_is_representable<TestFileTimeT<int64_t>, int64_t,
>>>> -                                 TestTimeSpec<int64_t, long>
>>>> >::test()));
>>>> -  assert((check_is_representable<TestFileTimeT<long long>, int32_t,
>>>> -                                 TestTimeSpec<int32_t, int32_t>
>>>> >::test()));
>>>> -
>>>> -  // Test that insane platforms like ppc64 linux, which use long
>>>> double as time_t,
>>>> -  // at least compile.
>>>> -  assert((check_is_representable<TestFileTimeT<long double>, double,
>>>> -                                 TestTimeSpec<long double, long>
>>>> >::test()));
>>>> +  { assert((test_case<file_time_type, time_t, struct
>>>> timespec>::test())); }
>>>> +  {
>>>> +    assert((test_case<TestFileTimeT<int64_t>, int64_t,
>>>> +                      TestTimeSpec<int64_t, long> >::test()));
>>>> +  }
>>>> +  {
>>>> +    assert((test_case<TestFileTimeT<long long>, int32_t,
>>>> +                      TestTimeSpec<int32_t, int32_t> >::test()));
>>>> +  }
>>>> +  {
>>>> +    // Test that insane platforms like ppc64 linux, which use long
>>>> double as time_t,
>>>> +    // at least compile.
>>>> +    assert((test_case<TestFileTimeT<long double>, double,
>>>> +                      TestTimeSpec<long double, long> >::test()));
>>>> +  }
>>>> +#ifndef TEST_HAS_NO_INT128_T
>>>> +  {
>>>> +    assert((test_case<TestFileTimeT<__int128_t, std::nano>, int64_t,
>>>> +                      TestTimeSpec<int64_t, long> >::test()));
>>>> +  }
>>>> +  {
>>>> +    assert((test_case<TestFileTimeT<__int128_t, std::nano>, int32_t,
>>>> +                      TestTimeSpec<int32_t, int32_t> >::test()));
>>>> +  }
>>>> +#endif
>>>>  }
>>>>
>>>> Modified:
>>>> libcxx/trunk/test/std/experimental/filesystem/fs.filesystem.synopsis/file_time_type.pass.cpp
>>>> URL:
>>>> http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/std/experimental/filesystem/fs.filesystem.synopsis/file_time_type.pass.cpp?rev=337960&r1=337959&r2=337960&view=diff
>>>>
>>>> ==============================================================================
>>>> ---
>>>> libcxx/trunk/test/std/experimental/filesystem/fs.filesystem.synopsis/file_time_type.pass.cpp
>>>> (original)
>>>> +++
>>>> libcxx/trunk/test/std/experimental/filesystem/fs.filesystem.synopsis/file_time_type.pass.cpp
>>>> Wed Jul 25 13:51:49 2018
>>>> @@ -17,15 +17,30 @@
>>>>  #include <chrono>
>>>>  #include <type_traits>
>>>>
>>>> +#include "test_macros.h"
>>>> +
>>>>  // system_clock is used because it meets the requirements of
>>>> TrivialClock,
>>>>  // and the resolution and range of system_clock should match the
>>>> operating
>>>>  // system's file time type.
>>>> -typedef std::chrono::system_clock              ExpectedClock;
>>>> -typedef std::chrono::time_point<ExpectedClock> ExpectedTimePoint;
>>>> +
>>>> +void test_trivial_clock() {
>>>> +  using namespace fs;
>>>> +  using Clock = file_time_type::clock;
>>>> +  ASSERT_NOEXCEPT(Clock::now());
>>>> +  ASSERT_SAME_TYPE(decltype(Clock::now()), file_time_type);
>>>> +  ASSERT_SAME_TYPE(Clock::time_point, file_time_type);
>>>> +  volatile auto* odr_use = &Clock::is_steady;
>>>> +  ((void)odr_use);
>>>> +}
>>>> +
>>>> +void test_time_point_resolution_and_range() {
>>>> +  using namespace fs;
>>>> +  using Dur = file_time_type::duration;
>>>> +  using Period = Dur::period;
>>>> +  ASSERT_SAME_TYPE(Period, std::nano);
>>>> +}
>>>>
>>>>  int main() {
>>>> -  static_assert(std::is_same<
>>>> -          fs::file_time_type,
>>>> -          ExpectedTimePoint
>>>> -      >::value, "");
>>>> +  test_trivial_clock();
>>>> +  test_time_point_resolution_and_range();
>>>>  }
>>>>
>>>> Modified:
>>>> libcxx/trunk/test/std/experimental/filesystem/fs.op.funcs/fs.op.last_write_time/last_write_time.pass.cpp
>>>> URL:
>>>> http://llvm.org/viewvc/llvm-project/libcxx/trunk/test/std/experimental/filesystem/fs.op.funcs/fs.op.last_write_time/last_write_time.pass.cpp?rev=337960&r1=337959&r2=337960&view=diff
>>>>
>>>> ==============================================================================
>>>> ---
>>>> libcxx/trunk/test/std/experimental/filesystem/fs.op.funcs/fs.op.last_write_time/last_write_time.pass.cpp
>>>> (original)
>>>> +++
>>>> libcxx/trunk/test/std/experimental/filesystem/fs.op.funcs/fs.op.last_write_time/last_write_time.pass.cpp
>>>> Wed Jul 25 13:51:49 2018
>>>> @@ -30,13 +30,86 @@
>>>>  #include <sys/stat.h>
>>>>  #include <iostream>
>>>>
>>>> +#include <fcntl.h>
>>>> +#include <sys/time.h>
>>>> +
>>>>  using namespace fs;
>>>>
>>>> -struct Times { std::time_t access, write; };
>>>> +using TimeSpec = struct ::timespec;
>>>> +using StatT = struct ::stat;
>>>> +
>>>> +using Sec = std::chrono::duration<file_time_type::rep>;
>>>> +using Hours = std::chrono::hours;
>>>> +using Minutes = std::chrono::minutes;
>>>> +using MicroSec = std::chrono::duration<file_time_type::rep,
>>>> std::micro>;
>>>> +using NanoSec = std::chrono::duration<file_time_type::rep, std::nano>;
>>>> +using std::chrono::duration_cast;
>>>> +
>>>> +#if defined(__APPLE__)
>>>> +TimeSpec extract_mtime(StatT const& st) { return st.st_mtimespec; }
>>>> +TimeSpec extract_atime(StatT const& st) { return st.st_atimespec; }
>>>> +#else
>>>> +TimeSpec extract_mtime(StatT const& st) { return st.st_mtim; }
>>>> +TimeSpec extract_atime(StatT const& st) { return st.st_atim; }
>>>> +#endif
>>>> +
>>>> +bool ConvertToTimeSpec(TimeSpec& ts, file_time_type ft) {
>>>> +  using SecFieldT = decltype(TimeSpec::tv_sec);
>>>> +  using NSecFieldT = decltype(TimeSpec::tv_nsec);
>>>> +  using SecLim = std::numeric_limits<SecFieldT>;
>>>> +  using NSecLim = std::numeric_limits<NSecFieldT>;
>>>> +
>>>> +  auto secs = duration_cast<Sec>(ft.time_since_epoch());
>>>> +  auto nsecs = duration_cast<NanoSec>(ft.time_since_epoch() - secs);
>>>> +  if (nsecs.count() < 0) {
>>>> +    if (Sec::min().count() > SecLim::min()) {
>>>> +      secs += Sec(1);
>>>> +      nsecs -= Sec(1);
>>>> +    } else {
>>>> +      nsecs = NanoSec(0);
>>>> +    }
>>>> +  }
>>>> +  if (SecLim::max() < secs.count() || SecLim::min() > secs.count())
>>>> +    return false;
>>>> +  if (NSecLim::max() < nsecs.count() || NSecLim::min() > nsecs.count())
>>>> +    return false;
>>>> +  ts.tv_sec = secs.count();
>>>> +  ts.tv_nsec = nsecs.count();
>>>> +  return true;
>>>> +}
>>>> +
>>>> +bool ConvertFromTimeSpec(file_time_type& ft, TimeSpec ts) {
>>>> +  auto secs_part =
>>>> duration_cast<file_time_type::duration>(Sec(ts.tv_sec));
>>>> +  if (duration_cast<Sec>(secs_part).count() != ts.tv_sec)
>>>> +    return false;
>>>> +  auto subsecs =
>>>> duration_cast<file_time_type::duration>(NanoSec(ts.tv_nsec));
>>>> +  auto dur = secs_part + subsecs;
>>>> +  if (dur < secs_part && subsecs.count() >= 0)
>>>> +    return false;
>>>> +  ft = file_time_type(dur);
>>>> +  return true;
>>>> +}
>>>> +
>>>> +bool CompareTimeExact(TimeSpec ts, TimeSpec ts2) {
>>>> +  return ts2.tv_sec == ts.tv_sec && ts2.tv_nsec == ts.tv_nsec;
>>>> +}
>>>> +bool CompareTimeExact(file_time_type ft, TimeSpec ts) {
>>>> +  TimeSpec ts2 = {};
>>>> +  if (!ConvertToTimeSpec(ts2, ft))
>>>> +    return false;
>>>> +  return CompareTimeExact(ts, ts2);
>>>> +}
>>>> +bool CompareTimeExact(TimeSpec ts, file_time_type ft) {
>>>> +  return CompareTimeExact(ft, ts);
>>>> +}
>>>> +
>>>> +struct Times {
>>>> +  TimeSpec access, write;
>>>> +};
>>>>
>>>>  Times GetTimes(path const& p) {
>>>>      using Clock = file_time_type::clock;
>>>> -    struct ::stat st;
>>>> +    StatT st;
>>>>      if (::stat(p.c_str(), &st) == -1) {
>>>>          std::error_code ec(errno, std::generic_category());
>>>>  #ifndef TEST_HAS_NO_EXCEPTIONS
>>>> @@ -46,22 +119,18 @@ Times GetTimes(path const& p) {
>>>>          std::exit(EXIT_FAILURE);
>>>>  #endif
>>>>      }
>>>> -    return {st.st_atime, st.st_mtime};
>>>> +    return {extract_atime(st), extract_mtime(st)};
>>>>  }
>>>>
>>>> -std::time_t LastAccessTime(path const& p) {
>>>> -    return GetTimes(p).access;
>>>> -}
>>>> +TimeSpec LastAccessTime(path const& p) { return GetTimes(p).access; }
>>>>
>>>> -std::time_t LastWriteTime(path const& p) {
>>>> -    return GetTimes(p).write;
>>>> -}
>>>> +TimeSpec LastWriteTime(path const& p) { return GetTimes(p).write; }
>>>>
>>>> -std::pair<std::time_t, std::time_t> GetSymlinkTimes(path const& p) {
>>>> -    using Clock = file_time_type::clock;
>>>> -    struct ::stat st;
>>>> -    if (::lstat(p.c_str(), &st) == -1) {
>>>> -        std::error_code ec(errno, std::generic_category());
>>>> +std::pair<TimeSpec, TimeSpec> GetSymlinkTimes(path const& p) {
>>>> +  using Clock = file_time_type::clock;
>>>> +  StatT st;
>>>> +  if (::lstat(p.c_str(), &st) == -1) {
>>>> +    std::error_code ec(errno, std::generic_category());
>>>>  #ifndef TEST_HAS_NO_EXCEPTIONS
>>>>          throw ec;
>>>>  #else
>>>> @@ -69,24 +138,10 @@ std::pair<std::time_t, std::time_t> GetS
>>>>          std::exit(EXIT_FAILURE);
>>>>  #endif
>>>>      }
>>>> -    return {st.st_atime, st.st_mtime};
>>>> +    return {extract_atime(st), extract_mtime(st)};
>>>>  }
>>>>
>>>>  namespace {
>>>> -bool TestSupportsNegativeTimes() {
>>>> -    using namespace std::chrono;
>>>> -    std::error_code ec;
>>>> -    std::time_t old_write_time, new_write_time;
>>>> -    { // WARNING: Do not assert in this scope.
>>>> -        scoped_test_env env;
>>>> -        const path file = env.create_file("file", 42);
>>>> -        old_write_time = LastWriteTime(file);
>>>> -        file_time_type tp(seconds(-5));
>>>> -        fs::last_write_time(file, tp, ec);
>>>> -        new_write_time = LastWriteTime(file);
>>>> -    }
>>>> -    return !ec && new_write_time <= -5;
>>>> -}
>>>>
>>>>  // In some configurations, the comparison is tautological and the test
>>>> is valid.
>>>>  // We disable the warning so that we can actually test it regardless.
>>>> Also, that
>>>> @@ -98,61 +153,131 @@ bool TestSupportsNegativeTimes() {
>>>>  #pragma clang diagnostic ignored "-Wtautological-constant-compare"
>>>>  #endif
>>>>
>>>> -bool TestSupportsMaxTime() {
>>>> -    using namespace std::chrono;
>>>> -    using Lim = std::numeric_limits<std::time_t>;
>>>> -    auto max_sec =
>>>> duration_cast<seconds>(file_time_type::max().time_since_epoch()).count();
>>>> -    if (max_sec > Lim::max()) return false;
>>>> -    std::error_code ec;
>>>> -    std::time_t old_write_time, new_write_time;
>>>> -    { // WARNING: Do not assert in this scope.
>>>> -        scoped_test_env env;
>>>> -        const path file = env.create_file("file", 42);
>>>> -        old_write_time = LastWriteTime(file);
>>>> -        file_time_type tp = file_time_type::max();
>>>> -        fs::last_write_time(file, tp, ec);
>>>> -        new_write_time = LastWriteTime(file);
>>>> -    }
>>>> -    return !ec && new_write_time > max_sec - 1;
>>>> -}
>>>> -
>>>> -bool TestSupportsMinTime() {
>>>> -    using namespace std::chrono;
>>>> -    using Lim = std::numeric_limits<std::time_t>;
>>>> -    auto min_sec =
>>>> duration_cast<seconds>(file_time_type::min().time_since_epoch()).count();
>>>> -    if (min_sec < Lim::min()) return false;
>>>> -    std::error_code ec;
>>>> -    std::time_t old_write_time, new_write_time;
>>>> -    { // WARNING: Do not assert in this scope.
>>>> -      scoped_test_env env;
>>>> -      const path file = env.create_file("file", 42);
>>>> -      old_write_time = LastWriteTime(file);
>>>> -      file_time_type tp = file_time_type::min();
>>>> -      fs::last_write_time(file, tp, ec);
>>>> -      new_write_time = LastWriteTime(file);
>>>> -    }
>>>> -    return !ec && new_write_time < min_sec + 1;
>>>> -}
>>>> -
>>>> -#if defined(__clang__)
>>>> -#pragma clang diagnostic pop
>>>> -#endif
>>>> -
>>>> -static const bool SupportsNegativeTimes = TestSupportsNegativeTimes();
>>>> -static const bool SupportsMaxTime = TestSupportsMaxTime();
>>>> -static const bool SupportsMinTime = TestSupportsMinTime();
>>>> +static const bool SupportsNegativeTimes = [] {
>>>> +  using namespace std::chrono;
>>>> +  std::error_code ec;
>>>> +  TimeSpec old_write_time, new_write_time;
>>>> +  { // WARNING: Do not assert in this scope.
>>>> +    scoped_test_env env;
>>>> +    const path file = env.create_file("file", 42);
>>>> +    old_write_time = LastWriteTime(file);
>>>> +    file_time_type tp(seconds(-5));
>>>> +    fs::last_write_time(file, tp, ec);
>>>> +    new_write_time = LastWriteTime(file);
>>>> +  }
>>>> +
>>>> +  return !ec && new_write_time.tv_sec < 0;
>>>> +}();
>>>> +
>>>> +static const bool SupportsMaxTime = [] {
>>>> +  using namespace std::chrono;
>>>> +  TimeSpec max_ts = {};
>>>> +  if (!ConvertToTimeSpec(max_ts, file_time_type::max()))
>>>> +    return false;
>>>> +
>>>> +  std::error_code ec;
>>>> +  TimeSpec old_write_time, new_write_time;
>>>> +  { // WARNING: Do not assert in this scope.
>>>> +    scoped_test_env env;
>>>> +    const path file = env.create_file("file", 42);
>>>> +    old_write_time = LastWriteTime(file);
>>>> +    file_time_type tp = file_time_type::max();
>>>> +    fs::last_write_time(file, tp, ec);
>>>> +    new_write_time = LastWriteTime(file);
>>>> +  }
>>>> +  return !ec && new_write_time.tv_sec > max_ts.tv_sec - 1;
>>>> +}();
>>>> +
>>>> +static const bool SupportsMinTime = [] {
>>>> +  using namespace std::chrono;
>>>> +  TimeSpec min_ts = {};
>>>> +  if (!ConvertToTimeSpec(min_ts, file_time_type::min()))
>>>> +    return false;
>>>> +  std::error_code ec;
>>>> +  TimeSpec old_write_time, new_write_time;
>>>> +  { // WARNING: Do not assert in this scope.
>>>> +    scoped_test_env env;
>>>> +    const path file = env.create_file("file", 42);
>>>> +    old_write_time = LastWriteTime(file);
>>>> +    file_time_type tp = file_time_type::min();
>>>> +    fs::last_write_time(file, tp, ec);
>>>> +    new_write_time = LastWriteTime(file);
>>>> +  }
>>>> +  return !ec && new_write_time.tv_sec < min_ts.tv_sec + 1;
>>>> +}();
>>>> +
>>>> +static const bool SupportsNanosecondRoundTrip = [] {
>>>> +  NanoSec ns(3);
>>>> +
>>>> +  // Test if the file_time_type period is less than that of
>>>> nanoseconds.
>>>> +  auto ft_dur = duration_cast<file_time_type::duration>(ns);
>>>> +  if (duration_cast<NanoSec>(ft_dur) != ns)
>>>> +    return false;
>>>> +
>>>> +  // Test that the system call we use to set the times also supports
>>>> nanosecond
>>>> +  // resolution. (utimes does not)
>>>> +  file_time_type ft(ft_dur);
>>>> +  {
>>>> +    scoped_test_env env;
>>>> +    const path p = env.create_file("file", 42);
>>>> +    last_write_time(p, ft);
>>>> +    return last_write_time(p) == ft;
>>>> +  }
>>>> +}();
>>>> +
>>>> +static const bool SupportsMinRoundTrip = [] {
>>>> +  TimeSpec ts = {};
>>>> +  if (!ConvertToTimeSpec(ts, file_time_type::min()))
>>>> +    return false;
>>>> +  file_time_type min_val = {};
>>>> +  if (!ConvertFromTimeSpec(min_val, ts))
>>>> +    return false;
>>>> +  return min_val == file_time_type::min();
>>>> +}();
>>>>
>>>>  } // end namespace
>>>>
>>>> -// In some configurations, the comparison is tautological and the test
>>>> is valid.
>>>> -// We disable the warning so that we can actually test it regardless.
>>>> Also, that
>>>> -// diagnostic is pretty new, so also don't fail if old clang does not
>>>> support it
>>>> -#if defined(__clang__)
>>>> -#pragma clang diagnostic push
>>>> -#pragma clang diagnostic ignored "-Wunknown-warning-option"
>>>> -#pragma clang diagnostic ignored "-Wunknown-pragmas"
>>>> -#pragma clang diagnostic ignored "-Wtautological-constant-compare"
>>>> -#endif
>>>> +static bool CompareTime(TimeSpec t1, TimeSpec t2) {
>>>> +  if (SupportsNanosecondRoundTrip)
>>>> +    return CompareTimeExact(t1, t2);
>>>> +  if (t1.tv_sec != t2.tv_sec)
>>>> +    return false;
>>>> +
>>>> +  auto diff = std::abs(t1.tv_nsec - t2.tv_nsec);
>>>> +
>>>> +  return diff < duration_cast<NanoSec>(MicroSec(1)).count();
>>>> +}
>>>> +
>>>> +static bool CompareTime(file_time_type t1, TimeSpec t2) {
>>>> +  TimeSpec ts1 = {};
>>>> +  if (!ConvertToTimeSpec(ts1, t1))
>>>> +    return false;
>>>> +  return CompareTime(ts1, t2);
>>>> +}
>>>> +
>>>> +static bool CompareTime(TimeSpec t1, file_time_type t2) {
>>>> +  return CompareTime(t2, t1);
>>>> +}
>>>> +
>>>> +static bool CompareTime(file_time_type t1, file_time_type t2) {
>>>> +  auto min_secs =
>>>> duration_cast<Sec>(file_time_type::min().time_since_epoch());
>>>> +  bool IsMin =
>>>> +      t1.time_since_epoch() < min_secs || t2.time_since_epoch() <
>>>> min_secs;
>>>> +
>>>> +  if (SupportsNanosecondRoundTrip && (!IsMin || SupportsMinRoundTrip))
>>>> +    return t1 == t2;
>>>> +  if (IsMin) {
>>>> +    return duration_cast<Sec>(t1.time_since_epoch()) ==
>>>> +           duration_cast<Sec>(t2.time_since_epoch());
>>>> +  }
>>>> +  file_time_type::duration dur;
>>>> +  if (t1 > t2)
>>>> +    dur = t1 - t2;
>>>> +  else
>>>> +    dur = t2 - t1;
>>>> +
>>>> +  return duration_cast<MicroSec>(dur).count() < 1;
>>>> +}
>>>>
>>>>  // Check if a time point is representable on a given filesystem. Check
>>>> that:
>>>>  // (A) 'tp' is representable as a time_t
>>>> @@ -162,22 +287,33 @@ static const bool SupportsMinTime = Test
>>>>  // (D) 'tp' is not 'file_time_type::min()' or the filesystem supports
>>>> the min
>>>>  //     value.
>>>>  inline bool TimeIsRepresentableByFilesystem(file_time_type tp) {
>>>> -    using namespace std::chrono;
>>>> -    using Lim = std::numeric_limits<std::time_t>;
>>>> -    auto sec = duration_cast<seconds>(tp.time_since_epoch()).count();
>>>> -    auto microsec =
>>>> duration_cast<microseconds>(tp.time_since_epoch()).count();
>>>> -    if (sec < Lim::min() || sec > Lim::max())   return false;
>>>> -    else if (microsec < 0 && !SupportsNegativeTimes) return false;
>>>> -    else if (tp == file_time_type::max() && !SupportsMaxTime) return
>>>> false;
>>>> -    else if (tp == file_time_type::min() && !SupportsMinTime) return
>>>> false;
>>>> -    return true;
>>>> +  TimeSpec ts = {};
>>>> +  if (!ConvertToTimeSpec(ts, tp))
>>>> +    return false;
>>>> +  else if (tp.time_since_epoch().count() < 0 && !SupportsNegativeTimes)
>>>> +    return false;
>>>> +  else if (tp == file_time_type::max() && !SupportsMaxTime)
>>>> +    return false;
>>>> +  else if (tp == file_time_type::min() && !SupportsMinTime)
>>>> +    return false;
>>>> +  return true;
>>>>  }
>>>>
>>>>  #if defined(__clang__)
>>>>  #pragma clang diagnostic pop
>>>>  #endif
>>>>
>>>> -TEST_SUITE(exists_test_suite)
>>>> +// Create a sub-second duration using the smallest period the
>>>> filesystem supports.
>>>> +file_time_type::duration SubSec(long long val) {
>>>> +  using SubSecT = file_time_type::duration;
>>>> +  if (SupportsNanosecondRoundTrip) {
>>>> +    return duration_cast<SubSecT>(NanoSec(val));
>>>> +  } else {
>>>> +    return duration_cast<SubSecT>(MicroSec(val));
>>>> +  }
>>>> +}
>>>> +
>>>> +TEST_SUITE(last_write_time_test_suite)
>>>>
>>>>  TEST_CASE(signature_test)
>>>>  {
>>>> @@ -202,21 +338,21 @@ TEST_CASE(read_last_write_time_static_en
>>>>          file_time_type ret = last_write_time(StaticEnv::File);
>>>>          TEST_CHECK(ret != min);
>>>>          TEST_CHECK(ret < C::now());
>>>> -        TEST_CHECK(C::to_time_t(ret) ==
>>>> LastWriteTime(StaticEnv::File));
>>>> +        TEST_CHECK(CompareTime(ret, LastWriteTime(StaticEnv::File)));
>>>>
>>>>          file_time_type ret2 =
>>>> last_write_time(StaticEnv::SymlinkToFile);
>>>> -        TEST_CHECK(ret == ret2);
>>>> -        TEST_CHECK(C::to_time_t(ret2) ==
>>>> LastWriteTime(StaticEnv::SymlinkToFile));
>>>> +        TEST_CHECK(CompareTime(ret, ret2));
>>>> +        TEST_CHECK(CompareTime(ret2,
>>>> LastWriteTime(StaticEnv::SymlinkToFile)));
>>>>      }
>>>>      {
>>>>          file_time_type ret = last_write_time(StaticEnv::Dir);
>>>>          TEST_CHECK(ret != min);
>>>>          TEST_CHECK(ret < C::now());
>>>> -        TEST_CHECK(C::to_time_t(ret) == LastWriteTime(StaticEnv::Dir));
>>>> +        TEST_CHECK(CompareTime(ret, LastWriteTime(StaticEnv::Dir)));
>>>>
>>>>          file_time_type ret2 = last_write_time(StaticEnv::SymlinkToDir);
>>>> -        TEST_CHECK(ret == ret2);
>>>> -        TEST_CHECK(C::to_time_t(ret2) ==
>>>> LastWriteTime(StaticEnv::SymlinkToDir));
>>>> +        TEST_CHECK(CompareTime(ret, ret2));
>>>> +        TEST_CHECK(CompareTime(ret2,
>>>> LastWriteTime(StaticEnv::SymlinkToDir)));
>>>>      }
>>>>  }
>>>>
>>>> @@ -230,15 +366,17 @@ TEST_CASE(get_last_write_time_dynamic_en
>>>>      const path dir = env.create_dir("dir");
>>>>
>>>>      const auto file_times = GetTimes(file);
>>>> -    const std::time_t file_write_time = file_times.write;
>>>> +    const TimeSpec file_write_time = file_times.write;
>>>>      const auto dir_times = GetTimes(dir);
>>>> -    const std::time_t dir_write_time = dir_times.write;
>>>> +    const TimeSpec dir_write_time = dir_times.write;
>>>>
>>>>      file_time_type ftime = last_write_time(file);
>>>> -    TEST_CHECK(Clock::to_time_t(ftime) == file_write_time);
>>>> +    TEST_CHECK(Clock::to_time_t(ftime) == file_write_time.tv_sec);
>>>> +    TEST_CHECK(CompareTime(ftime, file_write_time));
>>>>
>>>>      file_time_type dtime = last_write_time(dir);
>>>> -    TEST_CHECK(Clock::to_time_t(dtime) == dir_write_time);
>>>> +    TEST_CHECK(Clock::to_time_t(dtime) == dir_write_time.tv_sec);
>>>> +    TEST_CHECK(CompareTime(dtime, dir_write_time));
>>>>
>>>>      SleepFor(Sec(2));
>>>>
>>>> @@ -253,18 +391,15 @@ TEST_CASE(get_last_write_time_dynamic_en
>>>>
>>>>      TEST_CHECK(ftime2 > ftime);
>>>>      TEST_CHECK(dtime2 > dtime);
>>>> -    TEST_CHECK(LastWriteTime(file) == Clock::to_time_t(ftime2));
>>>> -    TEST_CHECK(LastWriteTime(dir) == Clock::to_time_t(dtime2));
>>>> +    TEST_CHECK(CompareTime(LastWriteTime(file), ftime2));
>>>> +    TEST_CHECK(CompareTime(LastWriteTime(dir), dtime2));
>>>>  }
>>>>
>>>>
>>>>  TEST_CASE(set_last_write_time_dynamic_env_test)
>>>>  {
>>>>      using Clock = file_time_type::clock;
>>>> -    using Sec = std::chrono::seconds;
>>>> -    using Hours = std::chrono::hours;
>>>> -    using Minutes = std::chrono::minutes;
>>>> -    using MicroSec = std::chrono::microseconds;
>>>> +    using SubSecT = file_time_type::duration;
>>>>      scoped_test_env env;
>>>>
>>>>      const path file = env.create_file("file", 42);
>>>> @@ -272,15 +407,17 @@ TEST_CASE(set_last_write_time_dynamic_en
>>>>      const auto now = Clock::now();
>>>>      const file_time_type epoch_time = now - now.time_since_epoch();
>>>>
>>>> -    const file_time_type future_time = now + Hours(3) + Sec(42) +
>>>> MicroSec(17);
>>>> -    const file_time_type past_time = now - Minutes(3) - Sec(42) -
>>>> MicroSec(17);
>>>> -    const file_time_type before_epoch_time = epoch_time - Minutes(3) -
>>>> Sec(42) - MicroSec(17);
>>>> +    const file_time_type future_time = now + Hours(3) + Sec(42) +
>>>> SubSec(17);
>>>> +    const file_time_type past_time = now - Minutes(3) - Sec(42) -
>>>> SubSec(17);
>>>> +    const file_time_type before_epoch_time =
>>>> +        epoch_time - Minutes(3) - Sec(42) - SubSec(17);
>>>>      // FreeBSD has a bug in their utimes implementation where the time
>>>> is not update
>>>>      // when the number of seconds is '-1'.
>>>>  #if defined(__FreeBSD__)
>>>> -    const file_time_type just_before_epoch_time = epoch_time - Sec(2)
>>>> - MicroSec(17);
>>>> +    const file_time_type just_before_epoch_time =
>>>> +        epoch_time - Sec(2) - SubSec(17);
>>>>  #else
>>>> -    const file_time_type just_before_epoch_time = epoch_time -
>>>> MicroSec(17);
>>>> +    const file_time_type just_before_epoch_time = epoch_time -
>>>> SubSec(17);
>>>>  #endif
>>>>
>>>>      struct TestCase {
>>>> @@ -300,7 +437,8 @@ TEST_CASE(set_last_write_time_dynamic_en
>>>>      };
>>>>      for (const auto& TC : cases) {
>>>>          const auto old_times = GetTimes(TC.p);
>>>> -        file_time_type old_time(Sec(old_times.write));
>>>> +        file_time_type old_time;
>>>> +        TEST_REQUIRE(ConvertFromTimeSpec(old_time, old_times.write));
>>>>
>>>>          std::error_code ec = GetTestEC();
>>>>          last_write_time(TC.p, TC.new_time, ec);
>>>> @@ -310,14 +448,8 @@ TEST_CASE(set_last_write_time_dynamic_en
>>>>
>>>>          if (TimeIsRepresentableByFilesystem(TC.new_time)) {
>>>>              TEST_CHECK(got_time != old_time);
>>>> -            if (TC.new_time < epoch_time) {
>>>> -                TEST_CHECK(got_time <= TC.new_time);
>>>> -                TEST_CHECK(got_time > TC.new_time - Sec(1));
>>>> -            } else {
>>>> -                TEST_CHECK(got_time <= TC.new_time + Sec(1));
>>>> -                TEST_CHECK(got_time >= TC.new_time - Sec(1));
>>>> -            }
>>>> -            TEST_CHECK(LastAccessTime(TC.p) == old_times.access);
>>>> +            TEST_CHECK(CompareTime(got_time, TC.new_time));
>>>> +            TEST_CHECK(CompareTime(LastAccessTime(TC.p),
>>>> old_times.access));
>>>>          }
>>>>      }
>>>>  }
>>>> @@ -325,9 +457,6 @@ TEST_CASE(set_last_write_time_dynamic_en
>>>>  TEST_CASE(last_write_time_symlink_test)
>>>>  {
>>>>      using Clock = file_time_type::clock;
>>>> -    using Sec = std::chrono::seconds;
>>>> -    using Hours = std::chrono::hours;
>>>> -    using Minutes = std::chrono::minutes;
>>>>
>>>>      scoped_test_env env;
>>>>
>>>> @@ -343,77 +472,75 @@ TEST_CASE(last_write_time_symlink_test)
>>>>      last_write_time(sym, new_time, ec);
>>>>      TEST_CHECK(!ec);
>>>>
>>>> -    const std::time_t new_time_t = Clock::to_time_t(new_time);
>>>>      file_time_type  got_time = last_write_time(sym);
>>>> -    std::time_t got_time_t = Clock::to_time_t(got_time);
>>>> +    TEST_CHECK(!CompareTime(got_time, old_times.write));
>>>> +    TEST_CHECK(got_time == new_time);
>>>>
>>>> -    TEST_CHECK(got_time_t != old_times.write);
>>>> -    TEST_CHECK(got_time_t == new_time_t);
>>>> -    TEST_CHECK(LastWriteTime(file) == new_time_t);
>>>> -    TEST_CHECK(LastAccessTime(sym) == old_times.access);
>>>> -    TEST_CHECK(GetSymlinkTimes(sym) == old_sym_times);
>>>> +    TEST_CHECK(CompareTime(LastWriteTime(file), new_time));
>>>> +    TEST_CHECK(CompareTime(LastAccessTime(sym), old_times.access));
>>>> +    std::pair<TimeSpec, TimeSpec> sym_times = GetSymlinkTimes(sym);
>>>> +    TEST_CHECK(CompareTime(sym_times.first, old_sym_times.first));
>>>> +    TEST_CHECK(CompareTime(sym_times.second, old_sym_times.second));
>>>>  }
>>>>
>>>>
>>>>  TEST_CASE(test_write_min_time)
>>>>  {
>>>>      using Clock = file_time_type::clock;
>>>> -    using Sec = std::chrono::seconds;
>>>> -    using MicroSec = std::chrono::microseconds;
>>>> -    using Lim = std::numeric_limits<std::time_t>;
>>>>      scoped_test_env env;
>>>>      const path p = env.create_file("file", 42);
>>>> -
>>>> -    std::error_code ec = GetTestEC();
>>>> +    const file_time_type old_time = last_write_time(p);
>>>>      file_time_type new_time = file_time_type::min();
>>>>
>>>> +    std::error_code ec = GetTestEC();
>>>>      last_write_time(p, new_time, ec);
>>>>      file_time_type tt = last_write_time(p);
>>>>
>>>>      if (TimeIsRepresentableByFilesystem(new_time)) {
>>>>          TEST_CHECK(!ec);
>>>> -        TEST_CHECK(tt >= new_time);
>>>> -        TEST_CHECK(tt < new_time + Sec(1));
>>>> -
>>>> -        ec = GetTestEC();
>>>> -        last_write_time(p, Clock::now());
>>>> +        TEST_CHECK(CompareTime(tt, new_time));
>>>>
>>>> -        new_time = file_time_type::min() + MicroSec(1);
>>>> +        last_write_time(p, old_time);
>>>> +        new_time = file_time_type::min() + SubSec(1);
>>>>
>>>> +        ec = GetTestEC();
>>>>          last_write_time(p, new_time, ec);
>>>>          tt = last_write_time(p);
>>>>
>>>>          if (TimeIsRepresentableByFilesystem(new_time)) {
>>>>              TEST_CHECK(!ec);
>>>> -            TEST_CHECK(tt >= new_time);
>>>> -            TEST_CHECK(tt < new_time + Sec(1));
>>>> +            TEST_CHECK(CompareTime(tt, new_time));
>>>> +        } else {
>>>> +          TEST_CHECK(ErrorIs(ec, std::errc::value_too_large));
>>>> +          TEST_CHECK(tt == old_time);
>>>>          }
>>>> +    } else {
>>>> +      TEST_CHECK(ErrorIs(ec, std::errc::value_too_large));
>>>> +      TEST_CHECK(tt == old_time);
>>>>      }
>>>>  }
>>>>
>>>> +TEST_CASE(test_write_max_time) {
>>>> +  using Clock = file_time_type::clock;
>>>> +  using Sec = std::chrono::seconds;
>>>> +  using Hours = std::chrono::hours;
>>>> +
>>>> +  scoped_test_env env;
>>>> +  const path p = env.create_file("file", 42);
>>>> +  const file_time_type old_time = last_write_time(p);
>>>> +  file_time_type new_time = file_time_type::max();
>>>> +
>>>> +  std::error_code ec = GetTestEC();
>>>> +  last_write_time(p, new_time, ec);
>>>> +  file_time_type tt = last_write_time(p);
>>>>
>>>> -
>>>> -TEST_CASE(test_write_min_max_time)
>>>> -{
>>>> -    using Clock = file_time_type::clock;
>>>> -    using Sec = std::chrono::seconds;
>>>> -    using Hours = std::chrono::hours;
>>>> -    using Lim = std::numeric_limits<std::time_t>;
>>>> -    scoped_test_env env;
>>>> -    const path p = env.create_file("file", 42);
>>>> -
>>>> -    std::error_code ec = GetTestEC();
>>>> -    file_time_type new_time = file_time_type::max();
>>>> -
>>>> -    ec = GetTestEC();
>>>> -    last_write_time(p, new_time, ec);
>>>> -    file_time_type tt = last_write_time(p);
>>>> -
>>>> -    if (TimeIsRepresentableByFilesystem(new_time)) {
>>>> -        TEST_CHECK(!ec);
>>>> -        TEST_CHECK(tt > new_time - Sec(1));
>>>> -        TEST_CHECK(tt <= new_time);
>>>> -    }
>>>> +  if (TimeIsRepresentableByFilesystem(new_time)) {
>>>> +    TEST_CHECK(!ec);
>>>> +    TEST_CHECK(CompareTime(tt, new_time));
>>>> +  } else {
>>>> +    TEST_CHECK(ErrorIs(ec, std::errc::value_too_large));
>>>> +    TEST_CHECK(tt == old_time);
>>>> +  }
>>>>  }
>>>>
>>>>  TEST_CASE(test_value_on_failure)
>>>> @@ -421,8 +548,7 @@ TEST_CASE(test_value_on_failure)
>>>>      const path p = StaticEnv::DNE;
>>>>      std::error_code ec = GetTestEC();
>>>>      TEST_CHECK(last_write_time(p, ec) == file_time_type::min());
>>>> -    TEST_CHECK(ec);
>>>> -    TEST_CHECK(ec != GetTestEC());
>>>> +    TEST_CHECK(ErrorIs(ec, std::errc::no_such_file_or_directory));
>>>>  }
>>>>
>>>>  TEST_CASE(test_exists_fails)
>>>> @@ -434,10 +560,30 @@ TEST_CASE(test_exists_fails)
>>>>
>>>>      std::error_code ec = GetTestEC();
>>>>      TEST_CHECK(last_write_time(file, ec) == file_time_type::min());
>>>> -    TEST_CHECK(ec);
>>>> -    TEST_CHECK(ec != GetTestEC());
>>>> +    TEST_CHECK(ErrorIs(ec, std::errc::permission_denied));
>>>>
>>>> -    TEST_CHECK_THROW(filesystem_error, last_write_time(file));
>>>> +    ExceptionChecker Checker(file, std::errc::permission_denied,
>>>> +                             "last_write_time");
>>>> +    TEST_CHECK_THROW_RESULT(filesystem_error, Checker,
>>>> last_write_time(file));
>>>> +}
>>>> +
>>>> +TEST_CASE(my_test) {
>>>> +  scoped_test_env env;
>>>> +  const path p = env.create_file("file", 42);
>>>> +  using namespace std::chrono;
>>>> +  using TimeSpec = struct ::timespec;
>>>> +  TimeSpec ts[2];
>>>> +  ts[0].tv_sec = 0;
>>>> +  ts[0].tv_nsec = UTIME_OMIT;
>>>> +  ts[1].tv_sec = -1;
>>>> +  ts[1].tv_nsec =
>>>> +      duration_cast<nanoseconds>(seconds(1) - nanoseconds(13)).count();
>>>> +  if (::utimensat(AT_FDCWD, p.c_str(), ts, 0) == -1) {
>>>> +    TEST_CHECK(false);
>>>> +  }
>>>> +  TimeSpec new_ts = LastWriteTime(p);
>>>> +  TEST_CHECK(ts[1].tv_sec == new_ts.tv_sec);
>>>> +  TEST_CHECK(ts[1].tv_nsec == new_ts.tv_nsec);
>>>>  }
>>>>
>>>>  TEST_SUITE_END()
>>>>
>>>>
>>>> _______________________________________________
>>>> cfe-commits mailing list
>>>> cfe-commits at lists.llvm.org
>>>> http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
>>>>
>>>
>>>
>
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