Merge from gnulib

This incorporates:
2017-05-01 New module 'localtime-buffer'
2017-04-30 utimens: Add support for native Windows
* admin/merge-gnulib (AVOIDED_MODULES): Add tzset.
* configure.ac (tzset): No need for Emacs itself to check now.
* lib/gettimeofday.c, lib/time.in.h, lib/time_rz.c, lib/utimens.c:
* m4/gettimeofday.m4, m4/time_h.m4, m4/time_rz.m4: Copy from gnulib.
* lib/gnulib.mk.in, m4/gnulib-comp.m4: Regenerate.
* lib/localtime-buffer.c, lib/localtime-buffer.h:
* m4/localtime-buffer.m4: New files, copied from gnulib.
* src/editfns.c (init_editfns): Assume tzset is callable.

1 files changed, 82 insertions, 0 deletions

diff --git a/lib/utimens.c b/lib/utimens.c
index 3b451193350..0b3b8e2f3af 100644
--- a/lib/utimens.c
+++ b/lib/utimens.c
@@ -35,6 +35,12 @@
 #include "stat-time.h"
 #include "timespec.h"
 
+#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+# define WIN32_LEAN_AND_MEAN
+# include <windows.h>
+# include "msvc-nothrow.h"
+#endif
+
 /* Avoid recursion with rpl_futimens or rpl_utimensat.  */
 #undef futimens
 #undef utimensat
@@ -271,6 +277,82 @@ fdutimens (int fd, char const *file, struct timespec const timespec[2])
   lutimensat_works_really = -1;
 #endif /* HAVE_UTIMENSAT || HAVE_FUTIMENS */
 
+#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+  /* On native Windows, use SetFileTime(). See
+     <https://msdn.microsoft.com/en-us/library/ms724933.aspx>
+     <https://msdn.microsoft.com/en-us/library/ms724284.aspx>  */
+  if (0 <= fd)
+    {
+      HANDLE handle;
+      FILETIME current_time;
+      FILETIME last_access_time;
+      FILETIME last_write_time;
+
+      handle = (HANDLE) _get_osfhandle (fd);
+      if (handle == INVALID_HANDLE_VALUE)
+        {
+          errno = EBADF;
+          return -1;
+        }
+
+      if (ts == NULL || ts[0].tv_nsec == UTIME_NOW || ts[1].tv_nsec == UTIME_NOW)
+        {
+          /* GetSystemTimeAsFileTime
+             <https://msdn.microsoft.com/en-us/library/ms724397.aspx>.
+             It would be overkill to use
+             GetSystemTimePreciseAsFileTime
+             <https://msdn.microsoft.com/en-us/library/hh706895.aspx>.  */
+          GetSystemTimeAsFileTime (&current_time);
+        }
+
+      if (ts == NULL || ts[0].tv_nsec == UTIME_NOW)
+        {
+          last_access_time = current_time;
+        }
+      else if (ts[0].tv_nsec == UTIME_OMIT)
+        {
+          last_access_time.dwLowDateTime = 0;
+          last_access_time.dwHighDateTime = 0;
+        }
+      else
+        {
+          ULONGLONG time_since_16010101 =
+            (ULONGLONG) ts[0].tv_sec * 10000000 + ts[0].tv_nsec / 100 + 116444736000000000LL;
+          last_access_time.dwLowDateTime = (DWORD) time_since_16010101;
+          last_access_time.dwHighDateTime = time_since_16010101 >> 32;
+        }
+
+      if (ts == NULL || ts[1].tv_nsec == UTIME_NOW)
+        {
+          last_write_time = current_time;
+        }
+      else if (ts[1].tv_nsec == UTIME_OMIT)
+        {
+          last_write_time.dwLowDateTime = 0;
+          last_write_time.dwHighDateTime = 0;
+        }
+      else
+        {
+          ULONGLONG time_since_16010101 =
+            (ULONGLONG) ts[1].tv_sec * 10000000 + ts[1].tv_nsec / 100 + 116444736000000000LL;
+          last_write_time.dwLowDateTime = (DWORD) time_since_16010101;
+          last_write_time.dwHighDateTime = time_since_16010101 >> 32;
+        }
+
+      if (SetFileTime (handle, NULL, &last_access_time, &last_write_time))
+        return 0;
+      else
+        {
+          #if 0
+          DWORD sft_error = GetLastError ();
+          fprintf (stderr, "utime SetFileTime error 0x%x\n", (unsigned int) sft_error);
+          #endif
+          errno = EINVAL;
+          return -1;
+        }
+    }
+#endif
+
   /* The platform lacks an interface to set file timestamps with
      nanosecond resolution, so do the best we can, discarding any
      fractional part of the timestamp.  */