RE: [PATCH] override HOME to isolate sbuild configuration

["Moessbauer, Felix" <felix.moessbauer@siemens.com>]

> -----Original Message-----
> From: Anton Mikanovich <amikan@ilbers.de>
> Sent: Friday, September 23, 2022 5:18 PM
> To: Moessbauer, Felix (T CED SES-DE) <felix.moessbauer@siemens.com>; Schild,
> Henning (T CED SES-DE) <henning.schild@siemens.com>
> Cc: isar-users@googlegroups.com; Bezdeka, Florian (T CED SES-DE)
> <florian.bezdeka@siemens.com>; ubely@ilbers.de
> Subject: Re: [PATCH] override HOME to isolate sbuild configuration
> 
> 20.09.2022 14:22, Moessbauer, Felix wrote:
> > I had the funny side effect that I could not build with ISAR on my sbuild +
> unshare enabled host.
> > Had a hard time to figure out why this did not work, especially as the sbuild
> man page is not very precise on the effect of the SBUILD_CONFIG env var.
> >
> > Setting HOME there is only relevant for the sbuild invocation and also there,
> the HOME variable is set but quite pointless as everything happens inside the
> schroot.
> > AFAIK there is no statement in the user_manual.md regarding the
> configuration of host tools.
> >
> > Let's put Anton in CC to get a statement from an maintainer of ISAR.
> >
> > Felix
> 
> Hello, Felix.
> 
> Thanks for pinging, I was sick a little bit this week, so unable to answer fast.
> 
> I think we can try to enable HOME override in the way like:
> 
> ISAR_BUILD_HOME ?= "${HOME}"
> ...
> export HOME="${ISAR_BUILD_HOME}"
> 
> This will allow user to override the value if needed, but still use the old one by
> default.

Hi Anton,

We could do it this way, but then the ISAR_BUILD_HOME would have to be injected from the users environment.
This would require an additional variable to be passed through various layers of shell-scripts and bitbake (and excluded from caching, etc...).
I already see people checking in the "ISAR_BUILD_HOME" variable in downstream layers' VCS.

Apart from that, I discovered that setting HOME itself is not sufficient to isolate the sbuildrc:
Still, /etc/sbuild/sbuild.conf is considered (but there are usually no breaking changes in it).

I personally use KAS anyways, there we don't have this issue.
But esp. Debian people who regularly use sbuild and want to try out ISAR will likely run into it.

Don't know how to proceed.
If nobody is interested in fixing this inconvenience, then let's keep it as it is.

Felix

> And this should be also documented.