Implement OpenRC support on Systemd based project

Message

archenroot · Post by **archenroot** » Tue Nov 07, 2017 2:42 pm

I am interested in adoption of miraclecast project which supports on Linux systems sharing screen on projectors via Wifi connection.
https://github.com/albfan/miraclecast

But it depends on SystemD....

I raised the request as well, but no asnwer so far:
https://bugs.gentoo.org/636016

I can do the ebuild myself, the real problem I would like to make the project compatible with OpenRC, not only SystemD and here I would welcome any kind of guide, etc. maybe it is very simple, but I don't know where and how to start to work on support.

Any online documents about this, or personal hints are more than welcomed.

Naib · Post by **Naib** » Tue Nov 07, 2017 3:04 pm

Do you know what aspects of systemd it depends upon? If it is just as a service start/stop then the unit file can easily be rewritten as an openrc unit file. If it is on logging login etc it may become ugly

eccerr0r · Post by **eccerr0r** » Tue Nov 07, 2017 3:15 pm

Quick check of the code looks like it's deeply in bed with systemd, at least it's using it for the automated nature of it and actually #includes <systemd header files>. It may well be that all that's needed is udev, but it won't be a simple task.

-> someone needs to be really enthusiastic about it and also a programmer to port it back from systemd.

So are there any capable volunteers?

I don't have the hardware so unfortunately it's a pass for me.

archenroot · Post by **archenroot** » Tue Nov 07, 2017 3:41 pm

I asked the creator to jump here as he is will to help. In meanwhile I created systemd virtual machine where I will do the ebuild limited to systemd and will wait if we find any "easy" solution to this. Thanks again guys for any hints.

albfan · Post by **albfan** » Mon Dec 25, 2017 6:57 am

Hi all, this is albfan, the miraclecast maintainer

Any access to instructions of that ebuild system? Would be cool to work on that or in the non systemd way.

There're people of other distros interested on package miraclecast properly, (like Red Hat with fedora) and there's cool things to work on, like delegate on NetworkManager WiFi Direct managing

bunder · Post by **bunder** » Mon Dec 25, 2017 9:21 am

albfan wrote:Any access to instructions of that ebuild system? Would be cool to work on that or in the non systemd way.

https://wiki.gentoo.org/wiki/Basic_guid ... oo_Ebuilds
https://wiki.gentoo.org/wiki/Package_Ma ... cification
https://wiki.gentoo.org/wiki/Submitting_ebuilds

Hopefully this should get you started. If you need more help, I'm sure someone here would be glad to help.

rburcham · Post by **rburcham** » Tue Dec 26, 2017 6:22 pm

Merry Xmas @albfan. I have a Samsung Allshare cast dongle, which I have read *should* be compatible, but if not I am willing to pick up the MS dongle and work with that. Let me know how I can help.

geki · Post by **geki** » Sat Mar 03, 2018 11:37 am

I had a quicklook at the miraclecast sources, which depend on systemd parts sd-bus, sd-daemon and sd-journal.

The TODO would be:
- extract sd-bus, sd-event, sd-id128 parts from libsystemd into libsd-bus; seems quite easy if you know meson build
- extend with syslog api; ifdef sd-journal else syslog endif example
- sd-daemon parts need a closer look

Replacing sd-bus api would be a major rework far more difficult and time-consuming than ripping sd-bus out of libsystemd somewhat like elogind.
I wonder if Yamakuzure - developer of elogind AFAIK - would help to get started.

Well, I had a look at how to extract sd-bus from systemd to get dbus-broker working without systemd for better performance(?) than old dbus.
I just have no spare time to actually do the necessary work these days.

So, if anyone is interested.

geki · Post by **geki** » Sat Mar 03, 2018 10:58 pm

I actually was in mood this evening ~ it seems I cannot trust myself these days

~ to strip sys-apps/systemd down to libsystemd with only sd-bus, sd-event, sd-id128 and sd-daemon.
I share my hacks, so if anyone feels like doing a clean independent meson.build, instead of patching. I just want to see, if dbus-broker works with this cleansed libsystemd. for funs sake(=ffs, right?

).

I do NOT recommend to merge the hacked systemd ebuild and source. You will trash your system. It needs above-mentioned cleanup and maybe renaming.

Patch to ebuild, source and finally files to cherry-pick.

geki · Post by **geki** » Sun Mar 04, 2018 8:38 am

Further discussion about extracting sd-bus from systemd may happen here: Extract sd-bus from systemd to build dbus-broker/miraclecast.

rburcham · Post by **rburcham** » Fri Jul 13, 2018 6:54 pm

@geki has refactored critical pieces of systemd into a practical libsd-bus complete with bundled busctl. That's pretty cool. We should even be able to build miraclecast too by referring to the libsd-bus includes.

That just leaves the connman dependecy... I have to assume that most systems are NetworkManager, meaning it would have to be disabled (and therefore networking disabled) in order for connman to be able to control the P2P wifi interface.

archenroot · Post by **archenroot** » Wed Oct 10, 2018 12:22 pm

make sense to me, maybe (if one day miraclecast ready for openrc) we could integrate it with NetworkManger via upstream reuqest and see if they will be interested.

I found some resource referring to this already on Fedora:
https://wiki.gnome.org/NetworkManager/WifiDirect

But no progress at all, still we have miraclecast ebuild available (on systemd):
viewtopic-t-1070784-start-0.html

And here is discussion about helping porting to openrc
viewtopic-t-1077936.html