[systemd-devel] RFC: creating a set of systemd RPM macros across distributions ?

[Frederic Crozat]

Le mardi 05 juillet 2011 à 23:39 +0200, Lennart Poettering a écrit :
> On Tue, 05.07.11 18:37, Frederic Crozat (fcrozat at suse.com) wrote:
> 
> > > > the point is to have a common macro which would allow packagers to
> > > > ensure they don't forget anything. The name of the package pulled by
> > > > this macro is not relevant.
> > > 
> > > Yeah, and again, it's just 'Requires: systemd', and I think no need to
> > > play distro-package indirection/abstraction games here.
> > 
> > No, it is :
> > Requires(post)
> > Requires(preun)
> > Requires(postun)
> > 
> > and from experience, people tends to forgot one or another. Using a
> > macro helps for readability and consistency.
> > 
> > But if you really don't want this macro, I guess it will be SUSE only..
> 
> Oh, we all want standardized systemd macros for RPM, there's not doubt
> on that. The question is just how exactly they should look like. And
> that means two things: first we have to agree how the macro should be
> called (and that implies figuring out policy of enabling and stuff,
> since we probably shouldn't suggest in the name of a macro that it does
> specific policy decisions if later on we decide to do policy completely
> differently -- for example with the preset stuff I just posted the RFC
> about), and secondly we have to agree how the default macro definitions
> should look like.

Agreed :)

> Kay just wanted to point out that the Requires(post) might not be the
> right choice to place in the default macross. 
> 
> The simple thing is that if we add this to systemd (or RPM, but I prefer
> systemd) then this will be something gazillions of packages will rely
> on, or will even copy, so we really should get it right. And that
> includes that we need to question every single line of it, which in this
> case raised some eyebrows on the usefulness of Requires(post) and
> friends if Requires is already in the header anyway.
> 
> The simple fact is that we need a dependency on systemd anyway in the
> RPMS to get the ownership for the units directory right. Now, if we have
> "Requires: systemd" in the header, why do we also need "Requires(post):
> systemd"? What does this buy us?

Requires(post/preun/postun) on the package containing systemctl is
needed as soon as systemctl is called in %post/preun/postun. A simple
Requires is not enough, because you might end up installing systemd and
the package requiring it in the same rpm transaction, but in the
incorrect order. 
-- 
Frederic Crozat <fcrozat at suse.com>
SUSE