profile library should check high-resolution timestamps if available

With the current profile code, it's possible for a file to be read when
partially written, with the writing of the new file contents being completed
within the same 1-second clock value, causing the profile code not to re-read
the contents.  Using a higher-resolution timestamp, available on many systems
now, should help reduce that window.  (Checking file sizes should also,
consider doing that separately.)

* configure.in: Check struct stat for fields st_mtimensec,
st_mtimespec.tv_nsec, and st_mtim.tv_usec.
* prof_file.c (profile_update_file_data): If one of them is found, use it as
the fractional part of the timestamp.  Do re-read the file if the fractional
parts don't match.
* prof_int.h (struct _prf_data_t): Add new field frac_ts.

ticket: new
status: open

git-svn-id: svn://anonsvn.mit.edu/krb5/trunk@17121 dc483132-0cff-0310-8789-dd5450dbe970

0 files changed, 0 insertions, 0 deletions