How to move storage OEMs to Samba 4.0 ?

[Alexander Bokovoy]

On Sat, Jun 23, 2012 at 10:22 AM, Andrew Bartlett <abartlet at samba.org> wrote:
> On Sat, 2012-06-23 at 09:23 +0300, Alexander Bokovoy wrote:
>> On Sat, Jun 23, 2012 at 1:40 AM, Andrew Bartlett <abartlet at samba.org> wrote:
>> > On Fri, 2012-06-22 at 08:35 -0700, Jeremy Allison wrote:
>> >> On Thu, Jun 21, 2012 at 10:10:16PM -0400, simo wrote:
>> >> >
>> >> > I would say also that the actual vfs ABI should not change, that doesn't
>> >> > mean the rest of samba internal are untouchable, but why penalize people
>> >> > that use exclusively the VFS interface as published ?
>> >> >
>> >> > I generally agree with all, although I would prefer if we made an effort
>> >> > not to change the VFS ABI in a minor release. I am not to ask to be
>> >> > strict about that, the vfs is large enough that we may not hold to the
>> >> > promise, but I would like to avoid seeing deliberate ABI change without
>> >> > a good reason .. "because we can"
>> >>
>> >> I agree. I wouldn't break the ABI without good cause also, but
>> >> we only promise API compatibility, just like the Linux kernel
>> >> and for the same reason.
>> >
>> > What is the VFS API?
>> >
>> > Does it include all the other Samba functions that a VFS module could
>> > potentially call?
>> >
>> > (As an example of what I mean, a passdb module AB wrote recently started
>> > calling become_root()/unbecome_root())
>> The module does not call become_root()/unbecome_root(). Instead, the
>> callback for smbldap SASL bind operation is called under
>> become_root()/unbecome_root() from within smbldap code. All passdb use
>> is actually done with become_root()/unbecome_root() already.
>
> Ahh, thanks.  But my memory is you did have a module that did this, and
> it worked?
Yes, it worked, but then we discussed on IRC with you and came to
conclusion it is better to move the wrapping where the call happens.

> Putting aside this example, my point is just that the functions in the
> Samba VFS API could potentially be quite broad.  For example, we
> maintained for ages some lp_ helpers, and I presume some modules call
> DEBUG().
Yes. An issue with 4.0 is that headers are not installed which would
allowed to build VFS modules for smbd at all. We'll need to get smbd
source3/include headers back into WAF build. For example,
source3/include/proto.h is not installed, making hard to build any VFS
module that uses lp_parm_const_string() or vfs_file_id_from_sbuf(). Or
vfs.h/vfs_macros.h.
-- 
/ Alexander Bokovoy