rsync - Mar 2008 - Rsync itemizing "t" (should be "T") when lutimes fails on recreated symlink

IIUC, the new philosophy of symlink times is that -t preserves them to
the extent that they are settable; when they aren't, it's just as if -t
wasn't given.  But rsync breaks this principle in the following case.

Suppose rsync is configured with HAVE_LUTIMES enabled but the lutimes
call doesn't actually work (I simulated this via the attached patch).
When rsync recreates a destination symlink to update its target path,
rsync will fail to preserve the time, but it nevertheless itemizes
"t".
It should itemize "T" because the time is being incidentally changed,
not preserved.

To reproduce:

ln -s ta a
sleep 1
ln -s tb b
rsync-dev -i -lt a b
stat --format='%Y %n' a b

Output:

# Rsync claims to have preserved the time...
cL..t...... a -> ta
# ... but it differs
1205122328 a
1205122329 b

The problem is that, for a recreated symlink (as opposed to a tweaked
one), the generator itemizes ITEM_REPORT_TIME whether it succeeded or
failed in setting the time.  On a push, the sender is doing the logging
and can't check the generator's FLAG_TIME_FAILED, so there is no way for
it to tell these two cases apart; they have to look different in the
itemize flags.

Matt
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On Mon, Mar 10, 2008 at 12:23:15AM -0400, Matt McCutchen
wrote:
> When rsync recreates a destination symlink to update its target path,
> rsync will fail to preserve the time, but it nevertheless itemizes
"t".
This is now fixed in the git repository along with a couple other
glitches that I turned up in the itemized output.  As a part of all the
fixing, I changed the itemized output of symlinks, devices, and special
files to put a 'c' into the checksum/change field.  This ensures that
changes that are happening show up in the itemized output and are able
to be differentiated from the copying of unchanged items when using the
--copy-dest option.

..wayne..

On Mon, 2008-03-10 at 21:44 -0700, Wayne Davison wrote:
> On Mon, Mar 10, 2008 at 12:23:15AM -0400, Matt McCutchen wrote:
> > When rsync recreates a destination symlink to update its target path,
> > rsync will fail to preserve the time, but it nevertheless itemizes
"t".
> 
> This is now fixed in the git repository along with a couple other
> glitches that I turned up in the itemized output.
Nice!  It works!  I see you also converted the non-symlink itemize
condition to a ?:, which I had been thinking of proposing.

Matt