Re: [PATCH v11 2/3] autoconf: xen: enable explicit preference option for xenstored preference

["Luis R. Rodriguez" <mcgrof@suse.com>]

On Mon, Sep 07, 2015 at 05:28:26PM +0100, George Dunlap wrote:
> On Wed, Jul 30, 2014 at 5:40 PM, Luis R. Rodriguez
> <mcgrof@do-not-panic.com> wrote:
> > From: "Luis R. Rodriguez" <mcgrof@suse.com>
> >
> > As it stands oxenstored will be used by default if ocaml tools are
> > found, the init system will also try to use oxenstored first if its
> > found otherwise the cxenstored will be used. Lets simplify the init
> > script and let users be explicit about the preference through configure.
> >
> > This adds support to let you be explicit about the xenstored preference,
> > you can only use one of these two options:
> >
> > ./configure --with-xenstored=xenstored
> > ./configure --with-xenstored=oxenstored
> >
> > We continue with the old behaviour and default oxenstored will be used
> > but only if you have ocaml dependencies. Since the xenstored preference
> > is explicit now and since we require configure substitutions for it we
> > make use of the AX_XEN_EXPAND_CONFIG() helpers as otherwise substitution
> > for SBINDIR is not propagated from the top level configuration.
> >
> > All this allows us to simplify the init script to use the configured
> > xenstore from the start. We update the sysconfig/default xencommons file
> > with the paths for the different options though, this can be used by
> > users to override the default xenstored, this follows the old behaviour
> > but we now just explicitly provide the full configured paths for users.
> 
> You keep saying "this follows the old behaviour", but it doesn't.
> Before, if I build oxenstored but put it in a separate package (say,
> xen-ocaml), it would run oxenstored if available, and if not run
> xenstored.  Now it will only try to run one, and if that's not
> available it will fail.  That's less of a feature IMHO.

George,

Wow, you're review is over 1 year late! You should have raised your concerns
when the patches were posted. I will note that I gave the community a shot at a
slew of options, one was a "laucher" solution [0] which would try one binary
first and then another, the solution we ended up using was what the community
decided, not me.

So -- if you'd like an alternative you can surely send a patch, but please
review early as well.

[0] http://lists.freedesktop.org/archives/systemd-devel/2014-June/019740.html

 Luis