#!/bin/bash
#
# lstape - Tool to show information about tape devices
#
# Copyright IBM Corp. 2003, 2018
#
# s390-tools is free software; you can redistribute it and/or modify
# it under the terms of the MIT license. See LICENSE for details.
#

CMD=$(basename $0)
SG_INQ=$(type -p sg_inq)

function RequireArgument() {
	if [ $2 -eq 1 ]; then
		echo "The $1 option requires an argument" >&2
	else
		echo "The $1 option requires $2 arguments" >&2
	fi
}

function PrintUsage() {
	cat <<-EOD | cut -c2-
	:Usage: $(basename $0) [<options>]
	:
	:	<options>
	:		-h|--help
	:			Print this help text.
	:		--ccw-only|--scsi-only
	:			Limit output to CCW or SCSI devices only.
	:		-t|--type <list of device types>
	:			Limit output of CCW tape devices to the given
	:			devices. The list consists of device types
	:			separated by ','. (e.g. -t 3480,3490)
	:		--online|--offline
	:			Show only devices that are either online or
	:			offline (only one option is allowed). This
	:			option only affects CCW devices.
	:		-s|--shortid
	:			Show only devices on channel subsytem 0 with
	:			subchannel set 0 and remove the leading '0.0.'
	:			from the displayed bus id (only affects the
	:			output of CCW devices).
	:		-V|--verbose
	:			Print additional information that does not fit
	:			into a single line (only affects the output for
	:			SCSI devices).
	:		-v|--version
	:			Display the version of the tools package and
	:			the lstape command.
	:
	:$(basename $0) without the --ccw-only option causes extra SAN traffic
	:for each SCSI tape or changer device by invoking the sg_inq command.
	EOD
}

function PrintVersion()
{
	cat <<-EOD
	$CMD: version %S390_TOOLS_VERSION%
	Copyright IBM Corp. 2003, 2018
	EOD
}

FLSEP=""
DEVLIST="3480,3490,3590"
SHORTID=false
SHOWCCW=true
VERBOSE=false
SHOWSCSI=true
FILTERONLINE=false
FILTEROFFLINE=false

while [ $# -ne 0 ]; do
	case $1 in
		-h|--help)
			PrintUsage
			exit 0
			;;
		-t|--type)
			if [ $# -lt 2 ]; then
				RequireArgument $1 1
				exit 1
			fi
			shift
			DEVLIST="$1"
			;;
		--online)
			if $FILTEROFFLINE; then
				echo -n "Option --online and --offline " >&2
				echo "are exclusive" >&2
				exit 1
			fi
			FILTERONLINE=true
			;;
		--offline)
			if $FILTERONLINE; then
				echo -n "Option --online and --offline " >&2
				echo "are exclusive" >&2
				exit 1
			fi
			FILTEROFFLINE=true
			;;
		-s|--shortid)
			SHORTID=true
			;;
		-v|--version)
			PrintVersion
			exit 0
			;;
		-V|--verbose)
			VERBOSE=true;
			;;
		--ccw-only)
			if ! $SHOWCCW; then
				echo "ERROR: --ccw-only after --scsi-only!" >&2
				exit 1
			fi
			SHOWSCSI=false;
			;;
		--scsi-only)
			if ! $SHOWSCSI; then
				echo "ERROR: --scsi-only after --ccw-only!" >&2
				exit 1
			fi
			SHOWCCW=false
			;;
		-*|--*)
			echo "$CMD: Invalid option $1" >&2
			echo "Try 'lstape --help' for more information." >&2
			exit 1
			;;
		*)
			FILTERLIST="$FILTERLIST$FLSEP$1"
			FLSEP=","
			;;
	esac
	shift
done

function SysfsCreateListCCW() {
	(
		find $1/bus/ccw/drivers/tape_34xx -type l \
			-printf '%f\n' 2>/dev/null
		find $1/bus/ccw/drivers/tape_3590 -type l \
			-printf '%f\n' 2>/dev/null
	) | awk -v format="$CCWFORMAT" '
		BEGIN{
			medium_state_str[0] = "UNKNOWN "
			medium_state_str[1] = "LOADED  "
			medium_state_str[2] = "UNLOADED"

			split("'$DEVLIST'", A, ",")
			for(i = 1; i in A; i++) {
				devlist[A[i]] = 1
			}
			shortid = "'$SHORTID'"=="true" ? 1 : 0
			filteronline = "'$FILTERONLINE'"=="true" ? 1 : 0
			filteroffline = "'$FILTEROFFLINE'"=="true" ? 1 : 0
		}
		function Read(file) {
			value = ""
			getline value <file
			close(file)
			return value
		}
		{
			bus_id = tolower($1)
			devdir = "'$1'/bus/ccw/devices/" bus_id

			devtype      = Read(devdir "/devtype")
			split(devtype, A, "/")
			if (!(A[1] in devlist))
				next

			online = Read(devdir "/online")
			if (filteronline && !online)
				next
			if (filteroffline && online)
				next

			cutype       = Read(devdir "/cutype")
			majmin = Read(devdir "/non-rewinding/dev")
			if (majmin != "") {
				split(majmin, A, ":")
				first_minor = A[2]
			} else {
				first_minor = Read(devdir "/first_minor")
			}
			if(first_minor == "")
				next

			if (online) {
				medium_state = Read(devdir "/medium_state")
				state        = Read(devdir "/state")
				operation    = Read(devdir "/operation")
				blocksize    = Read(devdir "/blocksize")
				if (blocksize == 0)
					blocksize = "auto"
			} else {
				state     = "OFFLINE"
				operation = "---"
				blocksize = "N/A"
			}

			if (shortid) {
				if (substr(bus_id, 1, 4) != "0.0.")
					next
				bus_id = substr(bus_id, 5)
			}

			printf(format,
				(online==0) ? "N/A" : first_minor / 2,
				bus_id,
				tolower(cutype),
				tolower(devtype),
				blocksize,
				state,
				operation,
				(online==0) ? "N/A" : \
					medium_state_str[medium_state])
		}
	' | sort 
}

# handle SCSI device not necessarily zfcp-attached, e.g. virtio-scsi-ccw
function SCSISearchCCWBusid()
{
	local SCSI_DEV=$1
	local SDEVCAN=$(readlink -e $SCSI_DEV)
	while [ -n "$SDEVCAN" ]; do
		# ascend to parent: strip last path part
		SDEVCAN=${SDEVCAN%/*}
		[ -h $SDEVCAN/subsystem ] || continue
		local SUBSYSTEM=$(readlink -e $SDEVCAN/subsystem)
		if [ "${SUBSYSTEM##*/}" = "ccw" ]; then
			echo ${SDEVCAN##*/}
			return
		fi
	done
	echo "N/A"
}

function SysfsCreateListSCSI()
{
	for SCSI_DEV in $1/bus/scsi/devices/*:*:*:*; do
		if [ ! -e $SCSI_DEV ]; then
			continue
		fi
		TYPE=$(cat $SCSI_DEV/type)
		case $TYPE in
			1)
				DEV_TYPE=tapedrv
				DEV_NAME=IBMtape
				;;
			8)
				DEV_TYPE=changer
				DEV_NAME=IBMchanger
				;;
			*)
				continue
		esac
		SCSI_LIST=$(ls -1d $SCSI_DEV/*)
		SCSI_ID=$(basename $SCSI_DEV)
		VENDOR=$(cat $SCSI_DEV/vendor)
		MODEL=$(cat $SCSI_DEV/model)
		STATE=$(cat $SCSI_DEV/state)
		SG_DEV=$(echo $SCSI_DEV/scsi_generic*)

		if [ -h $SG_DEV ]; then
			# deprecated sysfs layout
			SG_DEV=$(echo $SG_DEV | awk -F: '{print $NF}')
		elif [ -d $SCSI_DEV/scsi_generic ]; then
			SG_DEV=$(basename $SG_DEV/*)
		else
			SG_DEV=""
		fi

		if [ -z "$SG_DEV" ]; then
			SG_DEV="N/A"
			TAPE_SERIAL="NO/SG"
		elif [ "$SG_INQ" != "" ]; then
			TAPE_SERIAL=$(
				sg_inq /dev/$SG_DEV |
				awk '/serial/{print $NF}'
			)
		else
			TAPE_SERIAL="NO/INQ"
		fi

		TAPE_DEV="N/A"
		if [ "$(echo "$SCSI_LIST"|grep scsi_tape)" != "" ]; then
			if [ -d $SCSI_DEV/scsi_tape ]; then
				TAPE_IDX=$(echo $SCSI_DEV/scsi_tape/st*[0-9] |
					   sed -e 's/.*scsi_tape\///')
			else
				# deprecated sysfs layout
				TAPE_IDX=$(
					echo "$SCSI_LIST" |
					awk -F: '/scsi_tape\:st[0-9]+$/{print $NF}'
				)
			fi
			if [ "$TAPE_IDX" != "" ]; then
				TAPE_DEV=$TAPE_IDX
			fi
		elif [ "$(echo "$SCSI_LIST"|grep scsi_changer)" != "" ]; then
			if [ -d $SCSI_DEV/scsi_changer ]; then
				CHG_IDX=$(echo $SCSI_DEV/scsi_changer/sch*[0-9] |
					  sed -e 's/.*scsi_changer\///')
			else
				# deprecated sysfs layout
				CHG_IDX=$(
					echo "$SCSI_LIST" |
					awk -F: '/scsi_changer\:sch[0-9]+$/{print $NF}'
				)
			fi
			if [ "$CHG_IDX" != "" ]; then
				TAPE_DEV=$CHG_IDX
			fi
		elif [ "$(echo "$SCSI_LIST"|grep lin_tape)" != "" ]; then
			# bash glob sorts so IBMtape0 comes before IBMtape0n
			local IBM_PATH=$(
				ls -1d $SCSI_DEV/lin_tape/$DEV_NAME[0-9]* |
				head -n 1)
			if [ -d "$IBM_PATH" ]; then
				IBM_IDX=${IBM_PATH##*/}
			else
				# deprecated sysfs layout
				IBM_IDX=$(
					echo "$SCSI_LIST" |
					awk -F: '/lin_tape\:'"$DEV_NAME"'[0-9]+$/{print $NF}'
				)
			fi
			if [ "$IBM_IDX" != "" ]; then
				TAPE_DEV=$IBM_IDX
			fi
		elif [ -r /proc/scsi/$DEV_NAME ]; then
				IBM_IDX=$(
					grep -wF "$SCSI_ID" /proc/scsi/$DEV_NAME |
					cut -d ' ' -f 1
				)
				if [ "$IBM_IDX" != "" ]; then
					TAPE_DEV=$DEV_NAME$IBM_IDX
				fi
		fi

		printf "$SCSIFORMAT" \
			$SG_DEV \
			$TAPE_DEV \
			$SCSI_ID \
			$VENDOR $MODEL \
			$DEV_TYPE \
			$STATE

		if $VERBOSE; then
			if [ -r $SCSI_DEV/hba_id ]; then
				HBA_ID=$(cat $SCSI_DEV/hba_id)
			else
				HBA_ID=$(SCSISearchCCWBusid $SCSI_DEV)
			fi
			WWPN="N/A"
			[ -r $SCSI_DEV/wwpn ] && WWPN=$(cat $SCSI_DEV/wwpn)
			printf "$SCSIVFORMAT" \
				"$HBA_ID" \
				"$WWPN" \
				$TAPE_SERIAL
		fi
	done
}

case $(uname -r|cut -d. -f1-2) in
	1.*|2.[012])
		echo "Not supported!" >&2
		exit 1
		;;
	2.3|2.4)
		SYSFS=false
		;;
	*)
		SYSFS=true
		if [ "$(cat /proc/filesystems|grep sysfs)" = "" ]; then
			echo "WARNING: no sysfs support." >&2
			SYSFS=false
		fi
		SYSFSDIR=$(cat /proc/mounts|awk '$3=="sysfs"{print $2; exit}')
		if [ "SYSFS" = "true" -a "$SYSFSDIR" = "" ]; then
			echo "WARNING: sysfs not mounted." >&2
			SYSFS=false
		fi
		if [ "$SYSFS" = "false" -a "$SHOWCCW" = "true" ]; then
			echo -n "WARNING: proc interface will not find offline"
			echo " devices on kernel $(uname -r|cut -d. -f1-2)."
			echo
		fi
		;;
esac

function ShowTapesCCW()
{
	if $SYSFS; then
		SysfsCreateListCCW $SYSFSDIR
	else
		if [ ! -r /proc/tapedevices ]; then
			echo "ERROR: neither proc nor sysfs found!" >&2
			return 1
		fi
		cat /proc/tapedevices
	fi | awk -v LIST="$FILTERLIST" '
		BEGIN{
			if(LIST != "")
				split(LIST, A, ",")
		}
		LIST != ""{
			for(i in A) {
				if(index($2, A[i]) > 0) {
					print $0
					next
				}
			}
			next
		}
		{
			print $0
		}
	'
}

if $SHOWCCW; then
	CCWFORMAT="%-7s %-10s %-12s %-15s %-7s %-7s %-7s %-8s\n"
	LIST=$(ShowTapesCCW)

	if [ "$LIST" = "" ]; then
		NUMCCW=0
	else
		NUMCCW=$(echo "$LIST"|wc -l)
	fi

	if $SHOWSCSI; then
		echo "FICON/ESCON tapes (found $NUMCCW):"
	fi
	printf "$CCWFORMAT" "TapeNo" "BusID" "CuType/Model" "DevType/Model" \
		"BlkSize" "State" "Op" "MedState"
	if [ $NUMCCW -gt 0 ]; then
		echo "$LIST"
	fi
fi
if $SHOWSCSI; then
	SCSIFORMAT="%-7s %-13s %-12s %-8s %-16s %-8s %s\n"
	SCSIVFORMAT="        %-8s      %-18s    %s\n"
	LIST=$(SysfsCreateListSCSI $SYSFSDIR)

	if [ "$LIST" = "" ]; then
		NUMSCSI=0
	else
		NUMSCSI=$(echo "$LIST"|wc -l)
		if $VERBOSE; then
			let "NUMSCSI/=2"
		fi
	fi

	if $SHOWCCW; then
		echo
		echo "SCSI tape devices (found $NUMSCSI):"
	fi
	printf "$SCSIFORMAT" "Generic" "Device" "Target" "Vendor" "Model" \
		"Type" "State"
	if $VERBOSE; then
		printf "$SCSIVFORMAT" "HBA" "WWPN" "Serial"
	fi
	if [ $NUMSCSI -gt 0 ]; then
		echo "$LIST"
	fi
fi

exit 0

