[Pkg-e-devel] Bug#836089: e17: don't run dbus-launch if XDG_RUNTIME_DIR/bus is available

[Simon McVittie]

Source: e17
Version: 0.17.6-1.1
Severity: normal
Tags: upstream
User: dbus at packages.debian.org
Usertags: dbus-launch dbus-launch-unless-dsba

As described in <https://lists.debian.org/debian-devel/2016/08/msg00554.html>
I'm trying to reduce how much dbus-launch is used in Debian.
e17 has code that explicitly runs dbus-launch if DBUS_SESSION_BUS_ADDRESS
isn't set.

The major D-Bus implementations (libdbus, GDBus, sd-bus) now have a
fallback code path, before trying X11 autolaunch, when
DBUS_SESSION_BUS_ADDRESS is unset: if XDG_RUNTIME_DIR is set, and
XDG_RUNTIME_DIR/bus exists, is a socket and is owned by the
process's uid, then they will use it. In particular, dbus-user-session
sets up that situation.

For the moment, dbus-user-session does make sure DBUS_SESSION_BUS_ADDRESS
is set, to be nice to packages that don't have this fallback path.
However, I'd like to avoid requiring that in future, by adapting
the dbus-launch code in session-starters like gnome-session and e17 to
look for XDG_RUNTIME_DIR/bus before trying dbus-launch.

The necessary change would look something like
<https://git.gnome.org/browse/gvfs/commit/?id=ac80e77f6e45a3b688238e1fbf5b8baba98b58b4>.

Thanks,
    S