[linux-cifs-client] Re: [PATCH] CIFS: convert all delimiters in prefix path to match unix extensions

[simo]

On Mon, 2008-02-25 at 07:37 -0500, Jeff Layton wrote:
> On Fri, 15 Feb 2008 15:08:03 -0500
> Jeff Layton <jlayton at redhat.com> wrote:
> 
> > On Fri, 15 Feb 2008 13:08:20 -0600
> > "Steve French" <smfrench at gmail.com> wrote:
> > 
> > > I don't think it is worth the trouble or memory to store the path
> > > twice although I don't mind handling the easy case in which we
> > > reconnect to Windows after being Samba, and log an error and/or refuse
> > > reconnect if we switch the other way on reconnect and there is a long
> > > prefixpath.
> > > 
> > > Your patch was not quite right since posix path support are an
> > > optional capability even if Unix Extensions are on.  This fixes the
> > > flag check and also adds a reconnect warning error for the case we
> > > discussed.   Thoughts?
> > > 
> > > http://git.kernel.org/?p=linux/kernel/git/sfrench/cifs-2.6.git;a=commit;h=11b6d6450c10066e83e19f6ff57d55678c3e9f13
> > > 
> > 
> > Good catch. The patch looks good to me.
> > 
> > I'll start work on a respun mount.cifs patch in the near future, and
> > I'll also see about adding a section about delimiters to the mount.cifs
> > manpage too.
> > 
> 
> Ok, I've gotten a few things off of my plate and am going to start
> working on respinning the userspace patch soon. That means that we need
> to decide on what sort of behavior we want mount.cifs to implement for
> converting delimiters.
> 
> We know that we want mount.cifs to send paths with '/' exclusively as a
> delimiter so that we can allow for embedded '\' in the path. As I see
> it, we have 3 possible approaches:
> 
> 1) autoconvert '\' to '/', but only where possible. This means the
> first 2 characters before the server piece and the character following
> it (presuming of course that '\' is never a valid character in a
> hostname or address). Everything else we would assume is set up
> correctly already.
> 
> 2) autoconvert '\' to '/' everywhere, but allow for some mechanism to
> escape embedded '\' characters (maybe convert double backslashes to
> embedded singles). 
> 
> 3) assume that the path is already using '/' as a delimiter, and don't
> try to convert anything. If we get a path with a backslash where we
> expect a slash, throw an error back to the user saying that we require
> '/' as a delimiter and anything else is invalid.
> 
> Personally, I think #3 would be the most clear for users. The downside
> is that it might break some existing setups that are currently
> functioning. #1 seems like it would be confusing to users and #2 seems
> like overkill to me.
> 
> I'm open to any of the three, however (or even another option if
> someone wants to suggest something). Regardless of which option we
> pick, I think a paragraph in the mount.cifs manpage clarifying
> delimiter usage is needed.
> 
> Thoughts?

I am for #3, and second choice #1

Simo.

-- 
Simo Sorce
Samba Team GPL Compliance Officer <simo at samba.org>
Senior Software Engineer at Red Hat Inc. <ssorce at redhat.com>