Running systemctl enable/disable/set-default/... with the --root
option under strace reveals that it accessed various files and
directories in the main fs, and not underneath the specified root.
This can lead to correct results only when the layout and
configuration in the container are identical, which often is not the
case. Fix this by adding the specified root to all file access
operations.
This patch does not handle some corner cases: symlinks which point
outside of the specified root might be interpreted differently than
they would be by the kernel if the specified root was the real root.
But systemctl does not create such symlinks by itself, and I think
this is enough of a corner case not to be worth the additional
complexity of reimplementing link chasing in systemd.
Also, simplify the code in a few places and remove an hypothetical
memory leak on error.
Most likely the facility needed is actual connectivity, rather than whether or not the
network managment daemon is running.
We also need to explicitly pull in the network-online.target, as it is not active by
default.
This means {systemd-networkd,NetworkManager}-wait-online.service, can be enabled by default
as part of network-online.target, and only delay boot when some service actively pulls it in.
See: <https://bugzilla.gnome.org/show_bug.cgi?id=728965>
Cc: Pavel Šimerda <psimerda@redhat.com>
Cc: Michal Sekletar <msekleta@redhat.com>