#!/bin/bash
#
# Created by Sebastian Grewe, Jammicron Technology
# Changes by Jasem Elayeb on 02.03.2016
# Chagnes by Jonny007-MKD on 06.02.2020
# JE: add Physical Disks Name RAID_DISKS
# JE: add Physical Disks Status DISKS_STATUS
# JE: add Array Names RAID_ARRAY
# J007: Only check a single array


if [ $# -lt 1 -o -z "$1" ]; then
	echo "ERROR: pass raid name as argument"
	exit 1;
fi

INPUT="/sys/block"
DEBUG=false
while [[ $# -gt 0 ]]; do
	case $1 in
		-r|--raid)	TARGET_RAID_NAME="$2"; shift;;
		-i|--input) INPUT="$2"; shift;;
		-d|--debug) DEBUG=true;;
		-?|--help)
			echo "Check /proc/mdstat. Arguments:"
			echo "--raid NAME: Raid name, e.g. md0"
			echo "--input FILE: Read from this file. Default: /proc/mdstat"
			exit 0
			;;
	esac
	shift
done

if [ -z "$TARGET_RAID_NAME" ]; then
	echo "ERROR: pass --raid as argument"
	exit 255
fi
INPUT="$INPUT/$TARGET_RAID_NAME/md"

if [ ! -d $INPUT ]; then
	echo "CRITICAL: RAID $TARGET_RAID_NAME not found in $INPUT"
	exit 2
fi

function log {
	if $DEBUG; then
		echo "  > $@"
	fi
}
NL=$'\n'
log "Reading from $INPUT"

STATE=							# string
LEVEL=							# int
SIZE_IN_BLOCKS="!"				# int
CHUNK_SIZE_IN_BYTES=			# size in bytes for chunks
NUM_DEVICES=0					# int with total number of devices in raid
NUM_ACTIVE_DEVICES=0			# int with number of active devices in raid
NUM_SPARE_DEVICES=0				# int with number of spare devices in raid
rYNC_ACTION=					# "idle", "check" or "recover"
SYNC_PROGRESS=					# float in percent
SYNC_SPEED=						# sync speed in K/s
declare -A DEVICE_STATE			# dict of strings. key = dev, value = state
declare -A FAULTY_DEVICES		# dict with only faulty devices. key = dev, value = true
declare -A TO_REPLACE_DEVICES	# dict of devices in raid that shall be replaced. key = dev, value = true

function getDataFromSys {
	# https://mjmwired.net/kernel/Documentation/md.txt

	LEVEL=$(<$INPUT/level)
	NUM_DEVICES=$(<$INPUT/raid_disks)
	CHUNK_SIZE_IN_BYTES=$(<$INPUT/chunk_size)
	SIZE_IN_BLOCKS=$(<$INPUT/component_size)
	STATE=$(<$INPUT/array_state)
	SYNC_ACTION=$(<$INPUT/sync_action)
	if [ "$SYNC_ACTION" != "idle" ]; then
		SYNC_PROGRESS=$(<$INPUT/sync_completed)
		SYNC_SPEED=$(<$INPUT/sync_speed)
	fi

	log "LEVEL =               $LEVEL"
	log "STATE =               $STATE"
	log "CHUNK_SIZE_IN_BYTES = $CHUNK_SIZE_IN_BYTES"
	log "SIZE_IN_BLOCKS =      $SIZE_IN_BLOCKS"
	log "SYNC_ACTION =         $SYNC_ACTION"
	log "SYNC_PROGRESS =   $SYNC_PROGRESS"
	log "SYNC_SPEED =      $SYNC_SPEED"

	for dev in `find $INPUT -type d -name 'dev-*' -printf "%f\n"`; do
		local deviceName=${dev:4}
		local slot=$(<$INPUT/$dev/slot)
		local state=$(<$INPUT/$dev/state)
		log "$dev [$slot] is '$state'"
		DEVICE_STATE[$deviceName]=$state
		case "$state" in
			*in_sync*) 			((NUM_ACTIVE_DEVICES++));;
			*writemostly*)		((NUM_ACTIVE_DEVICES++));;
			*faulty*) 			FAULTY_DEVICES[$deviceName]=true;;
			*blocked*)	 		FAULTY_DEVICES[$deviceName]=true;;
			*write-error*)		TO_REPLACE_DEVICES[$deviceName]=true;;
			*want_replacement*)	TO_REPLACE_DEVICES[$deviceName]=true;;
			*replacement*)		((NUM_SPARE_DEVICES++));;
			*spare*)			((NUM_SPARE_DEVICES++));;
			*)			 		FAULTY_DEVICES[$deviceName]=true;;
		esac
	done

	log "NUM_DEVICES =         $NUM_DEVICES"
	log "NUM_ACTIVE_DEVICES =  $NUM_ACTIVE_DEVICES"
	log "NUM_SPARE_DEVICES =   $NUM_SPARE_DEVICES"
	log "FAULTY_DEVICES =      ${FAULTY_DEVICES[*]}"
	log "TO_REPLACE_DEVICES =  ${TO_REPLACE_DEVICES[*]}"

	if [ "$SYNC_ACTION" != "idle" ]; then
		SYNC_NUM=${SYNC_PROGRESS% /*}
		log "'$SYNC_NUM'"
		SYNC_DEN=${SYNC_PROGRESS#*/ }
		log "'$SYNC_DEN'"
		SYNC_PERCENT=$(($SYNC_NUM*100/$SYNC_DEN))
		BLOCK_SIZE=$(<$(dirname $INPUT)/queue/hw_sector_size)
		SYNC_REMAINING_S=$(( ($SYNC_DEN-$SYNC_NUM)*$BLOCK_SIZE/1024/$SYNC_SPEED))
		SYNC_REMAINING_MIN=$(($SYNC_REMAINING_S/60))
	fi
}

function printOutputAndExit {
	local result=""
	local info=""

	if [ $NUM_ACTIVE_DEVICES -lt $NUM_DEVICES ]; then
		result="CRITICAL"
		if [ -n "$info" ]; then info="$info. "; fi
		info="${info}Missing $(($NUM_DEVICES - $NUM_ACTIVE_DEVICES)) of $NUM_DEVICES devices"
	fi

	if [ ${#FAULTY_DEVICES[@]} -gt 0 ]; then
		result="CRITICAL"
		if [ -n "$info" ]; then info="$info. "; fi
		info="${info}These devices failed: ${!FAULTY_DEVICES[@]}"
	fi

	if [ ${#TO_REPLACE_DEVICES[@]} -gt 0 ]; then
		if [ -z "$result" ]; then result="WARNING"; fi
		if [ -n "$info" ]; then info="$info. "; fi
		info="${info}These devices should be replaced: ${!TO_REPLACE_DEVICES[@]}"
	fi

	if [ "$SYNC_ACTION" == "recover" ]; then
		if [ -z "$result" ]; then result="WARNING"; fi
		if [ -n "$info" ]; then info="$info. "; fi
		info="${info}Recovering: $SYNC_PERCENT%, remaining ${SYNC_REMAINING_MIN}min"
	fi
	if [ "$SYNC_ACTION" == "check" ]; then
		if [ -n "$info" ]; then info="$info. "; fi
		info="${info}Checking: $SYNC_PERCENT%, remaining ${SYNC_REMAINING_MIN}min"
	fi

	if [ -z "$result" ]; then result="OK"; fi

	echo -n "$result"
	if [ -n "$info" ]; then
		echo -n ": $info"
	fi

	echo -n " |"
	echo -n " 'raid level: $LEVEL'=0"
	echo -n " 'size in blocks'=$SIZE_IN_BLOCKS"
	echo -n " 'num devices'=$NUM_DEVICES"
	echo -n " 'num active devices'=$NUM_ACTIVE_DEVICES;;;0;$NUM_DEVICES"
	echo -n " 'num failed devices'=${#FAILED_DEVICES[@]};;1;0;$NUM_DEVICES"
	echo -n " 'num spare devices'=$NUM_SPARE_DEVICES;;;0"
	if [ "$SYNC_ACTION" != "idle" ]; then
		echo -n " 'sync progress'=$SYNC_NUM;0;;0;$SYNC_DEN"
		echo -n " 'sync speed [1/s]'=${SYNC_SPEED}K"
		echo -n " 'sync remaining'=${SYNC_REMAINING_S}s"
	fi
	for dev in ${!DEVICE_STATE[@]}; do
		echo -n " 'dev $dev: ${DEVICE_STATE[$dev]}"
		if [ -n "${FAULTY_DEVICE[$dev]}" ]; then
			echo -n " faulty"
		fi
		if [ -n "${TO_REPLACE_DEVICE[$dev]}" ]; then
			echo -n " wants replacement"
		fi
		echo -n "'=0"
	done

	echo

	case $result in
		OK)       exit 0;;
		WARNING)  exit 1;;
		CRITICAL) exit 2;;
	esac
}


getDataFromSys
printOutputAndExit