On Jan 25 12:24, Ken Brown via Cygwin-patches wrote:
> Following POSIX, ensure that ctime is updated if chown succeeds,
> unless the new owner is specified as (uid_t)-1 and the new group is
> specified as (gid_t)-1. Previously, ctime was unchanged whenever the
> owner and group were both unchanged.
>
> Aside from POSIX compliance, this fix makes gnulib report that chown
> works on Cygwin. This improves the efficiency of packages like GNU
> tar that use gnulib's chown module. Previously such packages would
> use a gnulib replacement for chown on Cygwin.
> ---
> winsup/cygwin/fhandler_disk_file.cc | 10 +++++++++-
> 1 file changed, 9 insertions(+), 1 deletion(-)
>
> diff --git a/winsup/cygwin/fhandler_disk_file.cc
> b/winsup/cygwin/fhandler_disk_file.cc
> index 07f9c513a..72d259579 100644
> --- a/winsup/cygwin/fhandler_disk_file.cc
> +++ b/winsup/cygwin/fhandler_disk_file.cc
> @@ -863,6 +863,7 @@ fhandler_disk_file::fchown (uid_t uid, gid_t gid)
> tmp_pathbuf tp;
> aclent_t *aclp;
> int nentries;
> + bool noop = true;
>
> if (!pc.has_acls ())
> {
> @@ -887,11 +888,18 @@ fhandler_disk_file::fchown (uid_t uid, gid_t gid)
> aclp, MAX_ACL_ENTRIES)) < 0)
> goto out;
>
> + /* According to POSIX, chown can be a no-op if uid is (uid_t)-1 and
> + gid is (gid_t)-1. Otherwise, even if uid and gid are unchanged,
> + we must ensure that ctime is updated. */
> if (uid == ILLEGAL_UID)
> uid = old_uid;
> + else
> + noop = false;
> if (gid == ILLEGAL_GID)
> gid = old_gid;
> - if (uid == old_uid && gid == old_gid)
Basically ok, but why not just
if (uid == ILLEGAL_UID && gid == ILLEGAL_GID)
instead of the noop var?
Corinna
