Am I right in thinking that taking the --disable-upower code path "does the right thing", because we already listen for login1's PrepareForSleep signal? If so, we could just delete that code (and you could --disable-upower on autobuilders in the meantime).

Indeed,

https://git.gnome.org/browse/gnome-continuous/commit/?id=0fb7473576f3413a8ec0a95645a169e1cd6f4688

Created attachment 87662 [details] [review]
Remove support for UPower

As of git master, it no longer has the API we use. On Linux, the
recommended way to be notified about suspend this week appears to
be logind, for which support was added in 5.15.1. Elsewhere, this
is a regression, but if UPower is deleting this functionality
we don't have much choice.

fwiw, UPower master isn't targetted for GNOME 3.10, but for GNOME 3.12.

(In reply to comment #4)
> fwiw, UPower master isn't targetted for GNOME 3.10, but for GNOME 3.12.

Mission Control 5.16.x has both UPower and logind suspend-detection, and is recommended for use with GNOME 3.10. 5.17.x (where I suggest this change) targets GNOME 3.12.

However, we do try to avoid being tied to particular GNOME releases: Telepathy is a cross-desktop project (also used in KDE, for a start), and we aim for it to be safe for distros to upgrade Telepathy while using the previous GNOME release.

If the UPower release that deletes this API will have a known version number, we could change the pkg-config check from [upower-glib] to [upower-glib < 0.10] or [upower-glib < 0.9.23] or something, resulting in our UPower support being disabled for newer upower-glib?

(That would be better for the 5.16.x branch, anyway - I'm not going to remove features from a stable-branch, but I wouldn't mind tightening the condition under which that feature is available.)

I'd rather not get into AC_CHECK_FUNC([up_client_suspend_sync]) or similar, since it doesn't combine well with pkg-config.

Comment on attachment 87662 [details] [review]
Remove support for UPower

Review of attachment 87662 [details] [review]:
-----------------------------------------------------------------

Not a tp-mission-control reviewer, but it does look to me like you've correctly deleted the code.

For what it's worth regarding non-systemd platforms, I think several projects like Upstart and OpenRC are looking at reimplementing the logind API.

Comment on attachment 87662 [details] [review]
Remove support for UPower

Review of attachment 87662 [details] [review]:
-----------------------------------------------------------------

Yep, looks good.

Fixed in git for 5.17.0.

I'm not going to remove this feature from 5.16.0. Please compile with --disable-upower to avoid the deprecated UPower functions.

If someone tells me the right "threshold" UPower version number for the branch that deleted these functions, I'd be OK with changing the PKG_CHECK_MODULES from

    PKG_CHECK_MODULES([UPOWER_GLIB], [upower-glib],

to something like

    PKG_CHECK_MODULES([UPOWER_GLIB], [upower-glib < 0.99],

for the 5.16 branch.

(In reply to comment #8)
> Fixed in git for 5.17.0.
> 
> I'm not going to remove this feature from 5.16.0. Please compile with
> --disable-upower to avoid the deprecated UPower functions.
> 
> If someone tells me the right "threshold" UPower version number for the
> branch that deleted these functions, I'd be OK with changing the
> PKG_CHECK_MODULES from
> 
>     PKG_CHECK_MODULES([UPOWER_GLIB], [upower-glib],
> 
> to something like
> 
>     PKG_CHECK_MODULES([UPOWER_GLIB], [upower-glib < 0.99],
> 
> for the 5.16 branch.

0.99.0 is the first release with the new API, so that should work.

*** Bug 96779 has been marked as a duplicate of this bug. ***

commit cbe4ec1a4e1167ce8231849bcbbdec44d48422f2
Author: George Kiagiadakis <gkiagia@tolabaki.gr>
Date:   Wed Jul 13 17:34:39 2016 +0300

    configure: do not enable upower support if upower is >=0.99
    
    The code doesn't compile anymore, the features used have been removed.
    The replacement is logind, for which support exists in MC since 5.15.1.
    
    https://bugs.freedesktop.org/show_bug.cgi?id=70458