This part of the copyright blurb stems from the GPL use recommendations:
https://www.gnu.org/licenses/gpl-howto.en.html
The concept appears to originate in times where version control was per
file, instead of per tree, and was a way to glue the files together.
Ultimately, we nowadays don't live in that world anymore, and this
information is entirely useless anyway, as people are very welcome to
copy these files into any projects they like, and they shouldn't have to
change bits that are part of our copyright header for that.
hence, let's just get rid of this old cruft, and shorten our codebase a
bit.
Files which are installed as-is (any .service and other unit files, .conf
files, .policy files, etc), are left as is. My assumption is that SPDX
identifiers are not yet that well known, so it's better to retain the
extended header to avoid any doubt.
I also kept any copyright lines. We can probably remove them, but it'd nice to
obtain explicit acks from all involved authors before doing that.
We don't have plural in the name of any other -util files and this
inconsistency trips me up every time I try to type this file name
from memory. "formats-util" is even hard to pronounce.
It's possible that sd_bus_creds_get_tty() fails and thus
scheduled_shutdown_tty is NULL in method_schedule_shutdown().
Fix logind_wall_tty_filter() to get along with that, by showing the message on
all TTYs, instead of crashing in strcmp().
https://launchpad.net/bugs/1553040
The files are named too generically, so that they might conflict with
the upstream project headers. Hence, let's add a "-util" suffix, to
clarify that this are just our utility headers and not any official
upstream headers.
So far we had two pretty much identical calls in user-util.[ch]:
lookup_uid() and uid_to_name(). Get rid of the former, in favour of the
latter, and while we are at it, rewrite it, to use getpwuid_r()
correctly, inside an allocation loop, as POSIX intended.
Add a timer to print UTMP wall messages so that it repeatedly informs users
about a scheduled shutdown:
* every 1 minute with less than 10 minutes to go
* every 15 minutes with less than 60 minutes to go
* every 30 minutes with less than 180 minutes (3 hours) to go
* every 60 minutes if more than that to go
This functionality only active if the .EnableWallMessages DBus property
is set to true. Also, a custom string can be added to the wall message,
set through the WallMessagePrefix property.