#!/bin/sh
#
# e2check

function on_ac_power() {
	local any_known=no

	# try sysfs power class first
	if [ -d /sys/class/power_supply ] ; then
		for psu in /sys/class/power_supply/* ; do
			if [ -r "${psu}/type" ] ; then
				type="`cat "${psu}/type"`"

				# ignore batteries
				[ "${type}" = "Battery" ] && continue

				online="`cat "${psu}/online"`"

				[ "${online}" = 1 ] && return 0
				[ "${online}" = 0 ] && any_known=yes
			fi
		done

		[ "${any_known}" = "yes" ] && return 1
	fi

	# else fall back to AC adapters in /proc
	if [ -d /proc/acpi/ac_adapter ] ; then
		for ac in /proc/acpi/ac_adapter/* ; do
			if [ -r "${ac}/state" ] ; then
				grep -q on-line "${ac}/state" && return 0
				grep -q off-line "${ac}/state" && any_known=yes
			elif [ -r "${ac}/status" ] ; then
				grep -q on-line "${ac}/status" && return 0
				grep -q off-line "${ac}/status" && any_known=yes
			fi
		done

		[ "${any_known}" = "yes" ] && return 1
	fi

	return 255
}

TMPFILE=`mktemp -t e2fsck.log.XXXXXXXXXX`

# be sure to delete the temp file
trap "rm $TMPFILE" EXIT

set -e

# pull in configuration -- don't bother with a parser, just use the shell's
. /etc/e2check.conf

# ensure VGS, VOLUMES, and SNAPSIZES have the same number of items
if [ "${#VGS[@]}" -ne "${#VOLUMES[@]}" ] || [ "${#VGS[@]}" -ne "${#SNAPSIZES[@]}" ] || \
		[ "${#VGS[@]}" -ne "${#INTERVALS[@]}" ] ; then
	echo "Error: Sizes of VGS, VOLUMES, SNAPSIZES, and INTERVALS arrays differ" >&2
	exit 1
fi

# check whether the machine is on AC power: if not, skip the e2fsck
if on_ac_power ; then
	for (( i=0; i<${#VGS[@]}; i+=1 )) ; do
		VOLUME="${VOLUMES[$i]}"
		VG="${VGS[$i]}"
		SNAPSIZE="${SNAPSIZES[$i]}"
		INTERVAL="${INTERVALS[$i]}"

		# get the last check time plus $INTERVAL days
		dumpe2fs -h "/dev/${VG}/${VOLUME}" | grep 'Last checked:' | \
			sed -e 's/Last checked:[[:space:]]*//' | while read check_date ; do
			check_day=`date --date="${check_date} $INTERVAL days" +"%Y%m%d"`
		done

		# get today's date
		today=`date +"%Y%m%d"`

		# skip LVs that don't need to be checked yet
		[ "$check_day" -gt "$today" ] && continue

		# clear the log file for each LV
		> $TMPFILE

		# use a different start time for each LV
		START="$(date +'%Y%m%d%H%M%S')"

		lvcreate -s -L ${SNAPSIZE} -n "${VOLUME}-snap" "${VG}/${VOLUME}"

		if nice logsave -as $TMPFILE e2fsck -p -C 0 "/dev/${VG}/${VOLUME}-snap" && \
				nice logsave -as $TMPFILE e2fsck -fy -C 0 "/dev/${VG}/${VOLUME}-snap" ; then
			echo 'Background scrubbing succeeded!'
			tune2fs -C 0 -T "${START}" "/dev/${VG}/${VOLUME}"
		else
			echo 'Background scrubbing failed! Reboot to fsck soon!'
			tune2fs -C 16000 -T "19000101" "/dev/${VG}/${VOLUME}"

			if test -n "$EMAIL"; then
				mail -s "E2fsck of /dev/${VG}/${VOLUME} failed!" $EMAIL < $TMPFILE
			fi
		fi

		lvremove -f "${VG}/${VOLUME}-snap"
	done
fi