Re: [meta-arm][PATCH v2 2/3] optee-client: Add sysVinit service

From: "Denys Dmytriyenko" <denis@denix.org>
To: Joshua Watt <JPEWhacker@gmail.com>
Cc: William Mills <wmills@ti.com>, meta-arm@lists.yoctoproject.org
Subject: Re: [meta-arm][PATCH v2 2/3] optee-client: Add sysVinit service
Date: Mon, 18 May 2020 14:58:43 -0400	[thread overview]
Message-ID: <20200518185843.GM11927@denix.org> (raw)
In-Reply-To: <2530da10-ae67-3f05-8afb-f3130cb9510c@gmail.com>

On Mon, May 18, 2020 at 01:03:01PM -0500, Joshua Watt wrote:
> 
> On 5/18/20 12:04 PM, William Mills wrote:
> >
> >On 5/17/20 12:44 PM, Denys Dmytriyenko wrote:
> >>On Fri, May 15, 2020 at 11:02:39AM -0500, Joshua Watt wrote:
> >>>Adds a sysVinit service to start tee-supplicant so that the optee-client
> >>>package can be used on distros where systemd is not used. Also does some
> >>>cleanup of the recipe including:
> >>>  1) Using @path@ tokens for replacemane in the .service file instead of
> >>>     paths
> >>>  2) Replacing tokens in the .service file after it is installed instead
> >>>     of editing the source file in ${WORKDIR}
> >>Overall looks fine. Quick question - if both sysvinit and systemd are in
> >>DISTRO_FEATURES - will it start tee-supplicant twice? This was never clear
> >>to me - I see some recipes go the extra mile to check the DISTRO_FEATURES
> >>and only install/enable the service accordingly, while some completely rely
> >>on the corresponding bbclass.
> >>
> >I had to look into this on ubuntu/debian recently.
> >systemd's sysvinit emulation will skip any sysvinit script that has the
> >same name as a *.service file.
> >
> > From [1]:
> >"""
> >systemd-sysv-generator generates the service units that run the van
> >Smoorenburg rc scripts from /etc/init.d, if it doesn't find a native
> >systemd service unit by that name already existing in the other six
> >locations.
> >"""
> >
> >I don't know if that is systemd default or Debian enhancement but OE
> >should follow that rule if it does not already IMHO.
> 
> systemd.bbclass and update-rc.d.bbclass work together to do the
> correct things based on the existence of the "sysvinit" and
> "systemd" DISTRO_FEATURES, so its fine to include both in a recipe.

So, if both are included and have the same name, systemd will skip the 
sysvinit emulation and load the correct service only once, correct?

> >This is not clear in the man pages [2][3].
> >
> >[1]
> >https://unix.stackexchange.com/questions/233468/how-does-systemd-use-etc-init-d-scripts
> >
> >[2]
> >http://manpages.ubuntu.com/manpages/bionic/man8/systemd-sysv-generator.8.html
> >
> >[3]
> >https://www.freedesktop.org/software/systemd/man/systemd-sysv-generator.html
> >
> >Bill

> 