#! /bin/sh
set +e	# ignore errors

# Triggering causes udev to reprocess all events, as if it were coldplugging
# the system. In some cases this can be unnecessary (or even cause
# problems!), and all you really want to do is settle - i.e. make sure that
# udev is up-to-date with events that have already been generated. On the
# other hand, if you install new modules, as d-i sometimes does, then you
# need to trigger to make sure that events that couldn't be processed due to
# missing modules are reprocessed.
#
# Thus, we have two modes: 'update-dev' triggers reprocessing of all events
# and waits for that to finish, while 'update-dev --settle' just waits for
# events that are already pending to be handled by userspace.

TRIGGER=:
if [ "$1" = --settle ]; then
	TRIGGER=false
fi

# Make sure /dev is up to date after loading modules.
if [ -x /lib/userdevfs/update-dev ]; then
       /lib/userdevfs/update-dev
elif type udevadm >/dev/null 2>&1; then
	udevadm control --reload
	if $TRIGGER; then
		udevadm trigger --action=add --subsystem-nomatch=sound --subsystem-nomatch=power_supply
	fi
	udevadm settle
else
	logger -t update-dev "warning: unable to find udevadm; skipping"
fi

exit 0