[Bug 1157122] [NEW] PrepareFor{Sleep, Shutdown} (false) signals not emitted

[Iain Lane]

Public bug reported:

Per

  http://www.freedesktop.org/wiki/Software/systemd/inhibit

"PrepareForShutdown(false) may be subscribed to by applications which
want to be notified about system resume events. Note that this will only
be sent out for suspend/resume cycles done via logind, i.e. generally
only for high-level user-induced suspend cycles, and not automatic, low-
level kernel induced ones which might exist on certain devices with more
aggressive power management. "

(I think it means s/Shutdown/Sleep in the first sentence)

Our systemd has a patch 0016-Add-poweroff-reboot-suspend-hibernate-
fallback.patch which calls the executables from pm-utils in the case
that the systemd D-Bus API isn't available (which is the case for us).
Usually, logind calls shutdown/suspend/... methods via systemd jobs. In
our case, since we call these executables directly, the jobs aren't used
and so the standard systemd Job* signals aren't sent. It's these signals
that logind listens for to know when to emit the
PrepareFor{Sleep,Shutdown} (false) signals.

I attach a strawman patch (diff of a diff - look at it after applying)
which explicitly sends the signal and does some other needed cleanups
(see bus_message_filter for the call site for where the signal is
usually sent). Let me know what you think.

** Affects: systemd (Ubuntu)
     Importance: Undecided
         Status: New

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to systemd in Ubuntu.
https://bugs.launchpad.net/bugs/1157122

Title:
  PrepareFor{Sleep,Shutdown} (false) signals not emitted

Status in “systemd” package in Ubuntu:
  New

Bug description:
  Per

    http://www.freedesktop.org/wiki/Software/systemd/inhibit

  "PrepareForShutdown(false) may be subscribed to by applications which
  want to be notified about system resume events. Note that this will
  only be sent out for suspend/resume cycles done via logind, i.e.
  generally only for high-level user-induced suspend cycles, and not
  automatic, low-level kernel induced ones which might exist on certain
  devices with more aggressive power management. "

  (I think it means s/Shutdown/Sleep in the first sentence)

  Our systemd has a patch 0016-Add-poweroff-reboot-suspend-hibernate-
  fallback.patch which calls the executables from pm-utils in the case
  that the systemd D-Bus API isn't available (which is the case for us).
  Usually, logind calls shutdown/suspend/... methods via systemd jobs.
  In our case, since we call these executables directly, the jobs aren't
  used and so the standard systemd Job* signals aren't sent. It's these
  signals that logind listens for to know when to emit the
  PrepareFor{Sleep,Shutdown} (false) signals.

  I attach a strawman patch (diff of a diff - look at it after applying)
  which explicitly sends the signal and does some other needed cleanups
  (see bus_message_filter for the call site for where the signal is
  usually sent). Let me know what you think.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1157122/+subscriptions