Journal phantomfive's Journal: 8 - Does Gnome depend on systemd, or just logind? 7
The previous entry investigated Gnome and logind, and found that practically speaking, Gnome does depend on logind. There are some alternatives, but they are not complete or well-maintained.
This entry discusses the dependency between logind and systemd.
Logind is deeply embedded in systemd. Here is a list of logind features, which seem like a grab-bag of vaguely related requirements. If anything, their relation seems to be they are goals of GnomeOS. Maybe Poettering looked at that list and tried to implement as many as possible to convince Gnome to adopt his software.
At a minimum we can say the name 'logind' is a poor choice for a name, since it does much more than that: the name doesn't describe what the product does.
Logind depends on systemd (for example) for calling unit scripts to shutdown or put the computer in sleep mode. In logind-dbus.c function execute_shutdown_or_sleep() you can see an example. Systemd also seems to be required for detecting hot-plugged devices and probably for other stuff. Note also there is a clear dependency on DBUS.
Logind is described as a tiny daemon. That's a lie, the thing has 15491 lines, with the largest file having 3023 lines (3023 lines is large but not necessarily bad).
As always, if you find any errors, please let me know. I'm trying to find the truth, not start fights.
misnomer (Score:2)
It makes a little more sense to me if I think of it as "whoisloggedind" rather than "letmelogind". (It gets used *AFTER* PAM has already logged the user in - it then tracks the login.)
As far as I can tell, the purpose of the various features is largely around being able to tell who is logged in where and what that implies about their hardware access. (Imagine a grown-up version of "/etc/shutdown.allow".)
As such, I don't see why it need to depend on systemd at all, and I've planned, but not got around to, wr
Re: (Score:2)
As such, I don't see why it need to depend on systemd at all, and I've planned, but not got around to, writing a version that keeps the same state information, but doesn't use systemd.
That's an interesting idea. For my next post I'm planning on investigating how stable the systemd APIs have been over time.
You can see the full API here [freedesktop.org] (as you probably already know). Note that a lot of the functionality is dealing with sleep/shutdown (and sending notifications of that).
Re: (Score:2)
Supposedly they tried to create such a independent tracker in the form of Consolekit.
You will find a fork of it at https://github.com/ConsoleKit2... [github.com].
It got forked because the project was shut down and left to rot by no other than Poettering, who was co-maintainer at the time.
False assumptions (Score:2)
I'm sorry, couldn't comment on your previous journal entries, but I think you're maybe going about this with a false set of assumptions.
For instance, regarding portability, you have apparently missed the part where Lennart explained that he's previously written portable software (e.g. PulseAudio) and that he knows about the tradeoffs. Maybe you think of the tradeoff differently, but it wasn't you who had to implement it so that's sort of a moot point.
Regarding GNOME's use of logind, you have to remember th
Re: (Score:2)
I'm sorry, couldn't comment on your previous journal entries, but I think you're maybe going about this with a false set of assumptions.
Thankyou for your suggestion. I'd like to enable comments on older entries, but I don't know how.
For instance, regarding portability, you have apparently missed the part where Lennart explained that he's previously written portable software (e.g. PulseAudio) and that he knows about the tradeoffs.
Yes, he has, so it would be reasonable to assume he understands how to do it. I don't know why he has so much trouble with it, but there he was (quote linked to in that journal), saying himself that to write portable software he'd need to have #ifdefs on every other line. Of course, that is false, and does produce ugly code.
Regarding GNOME's use of logind, you have to remember that ConsoleKit was dead. Instead systemd showed up with manpower and momentum. This is actually common theme among many of the small utilities bundled with systemd.
Yeah, you are right. The point of this series is to examine code quality though......if p
Re: (Score:2)
Yeah, Consolekit was dead. This in large part to the same people that are so heavily pushing systemd...
GnomeOS?! (Score:2)
Well that explains quite a bit...
Btw. While Gnome exist as a "independent" foundation, quite a number of the core devs seems to work for Red Hat. This to the point that some of them use Gnome blogs to talk about Red Hat news from the insider perspective.