[PATCHSET]: let configure(waf) fail if --with-ads was specified but ad support was not found

[Andrew Bartlett]

On Fri, 2012-11-02 at 13:59 +0100, Michael Adam wrote:
> On 2012-11-02 at 23:26 +1100, Andrew Bartlett wrote:
> > 
> > You are not missing anything.  Back in May or so we talked about having
> > Samba require krb5, ldap and ACL headers by default, so users would not
> > be surprised by the lack of these features in compiled binaries.  It
> > would make --with-ads the default, and require an explicit --without-ads
> > if you didn't want it.
> 
> Ah, now I understand your point. :-)
> 
> The above would be achieved by failing configure if "with_ads" was
> set to True and support was not found. And of course letting the default
> at "true" where it currently is.
> 
> The proposed patchset does a bit more: It lets configure fail
> if --with-ads is specified, but it adds the None default, which
> is effectively the auto mode, thereby _not_ changing the default
> behaviour.
> 
> Not reading back the discussions, I think the default to "auto"
> is quite reasonable. If you don't specify anyhting, you'll get
> what is there. If you want to enforce it (like packagers will),
> you specify --with-ads, and then you don't get surprises.
> 
> This is exactly the mode that distributors are used to from
> the s3 autoconf build.
> 
> What do you think?
> Thanks - Michael

This all started because at the time, a large number of users trying out
the then-new samba3upgrade (now samba-tool domain classicupgrade) code
had it fail, because Samba built without ldap headers.  Nothing at build
time warned them (or warned them clearly enough) that they were missing
this feature.  

The same happened with ACLs, getting to the point that I had to add a
clear test to the provision stage to give a clear 'you didn't build with
ACL headers' error.  (For smbd file server users, it is even less clear,
as there are no errors, just less features). 

The users would eventually rebuild, but felt that configure should have
made it harder to proceed to build something less than 'the complete
samba'. 

It hasn't come up as much recently, as we changed the list of packages
in the Samba4 HOWTO to include the critical packages here.  I still
think we should encourage a situation where users have to explicitly
choose to build without these important features.

Andrew Bartlett

-- 
Andrew Bartlett                                http://samba.org/~abartlet/
Authentication Developer, Samba Team           http://samba.org