D-Bus: fix shutdown race condition after aborted sync

When a sync in syncevo-dbus-helper was aborted, the process did not
wait in main() for the server to acknowledge the D-Bus method
response. If the process quit to early, the parent did not get the
method response, leading to an "internal error" instead of "aborted"
as result of the sync.

The reason is that the acknowledgement was meant to be done via
SIGTERM, but that had already been sent and thus syncevo-dbus-helper
did not wait. Solved by using SIGURG for the acknowledgement.

In addition, the parent must not close its connection when sending
signals to the child, because the child may still need to send its
sync report and/or log output signals.

0 files changed, 0 insertions, 0 deletions