bug#63982: Shepherd can crash when a user service fails to start

[Ludovic Courtès]

Hi,

Maxim Cournoyer <maxim.cournoyer@gmail.com> skribis:

>> I believe this is fixed by Shepherd commit
>> 24c964021ebd3d63ce6e22808dd09dbe16116a6c, which introduces an additional
>> change: loading the config file asynchronously.
>
> Nitpick: I'd use a git message tag for 'Reported-by', as can be inserted
> in the commit buffer in Magit with C-c C-p.  They should be placed at
> the bottom of the git message to be considered by tools parsing them.

Neat, I didn’t know about it, I’ll do that now (I think I started using
the “Reported by” convention before Git came into existence…).

>> If you wish to test it, you can use the ‘shepherd’ channel.
>
> I've done so by placing in my ~/.config/guix/channels.scm file:
>
>        (channel
>         (name 'shepherd)
>         (url "https://git.savannah.gnu.org/git/shepherd.git";)
>         (introduction
>          (make-channel-introduction
>           "788a6d6f1d5c170db68aa4bbfb77024fdc468ed3"  ;2022-05-21
>           (openpgp-fingerprint
>            "3CE4 6455 8A84 FDC6 9DB4  0CFB 090B 1199 3D9A EBB5"))))
>            
>
> It'd be nice to have this in the Shepherd doc for easy copy & paste.

I’ll add that to ‘README’.

>> Let me know how it goes!
>
> I've edited my ~/.xsession file to use
> /gnu/store/ahzl8vxxcd5bqlljwgn8wkp4884sr72l-shepherd-0.10.99-tarball,
> and I'm now seeing this:
>
> $ herd status
> Démarrés :
>  + root
> Starting:
>  ^ emacs
> Arrêtés :
>  - gpg-agent
>  - ibus-daemon
>  - jackd
>  - workrave

Uh, so it remains in “starting” state?

> Interestingly, the Emacs client is usable.  It doesn't change from
> there, and requesting it to be stopped hangs Shepherd:

Technically it’s waiting for ‘emacs’ to be in “running” state before
attempting to stop it.

> If I comment out the Emacs service from the ~/.config/shepherd/init.scm
> file, the same seems to happen on my next service, gpg-agent:
>
> $ herd status
> Démarrés :
>  + root
> Starting:
>  ^ gpg-agent
> Arrêtés :
>  - emacs
>  - ibus-daemon
>  - jackd
>  - workrave
>
> Etc. if I comment that one (now hanging on starting ibus-daemon).  It
> seems something is still off?

Looks like it.  Could you share ~/.local/var/log/shepherd.log?

Thanks,
Ludo’.