Updater-unstuck.sh

#!/bin/busybox sh

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# Script to drop a stale updater lock and kill updater if it is found

STATE_DIR=/tmp/update-state
LOCK_DIR="$STATE_DIR/lock"
STALE_MARK="$LOCK_DIR/stale"

if [ -f "$STALE_MARK" ] ; then
	# We marked the lock as stale previously. It is still marked. It's there for at least two runs (2 days), kill the updater if it runs and clean the lock.
	echo 'Cleaning stale lock' | logger -t updater -p daemon.error
	killall updater.sh
	sleep 1
	killall -9 updater.sh
	rm -rf "$LOCK_DIR"
elif [ -d "$LOCK_DIR" ] ; then
	echo 'Marking lock as stale, waiting another day to see if it stays here' | logger -t updater -p daemon.warning
	touch "$STALE_MARK"
fi