#!/bin/sh
#
# Copyright (C) 2010 Red Hat, Inc. All rights reserved.
#
# This file is part of the device-mapper-multipath package.
#
# This copyrighted material is made available to anyone wishing to use,
# modify, copy, or redistribute it subject to the terms and conditions
# of the GNU General Public License v.2.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software Foundation,
# Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

#
# Simple editting of /etc/multipath.conf
# This program was largely ripped off from lvmconf
#

unset ENABLE FIND FRIENDLY MODULE MULTIPATHD HAVE_DISABLE HAVE_FIND HAVE_BLACKLIST HAVE_DEFAULTS HAVE_FRIENDLY HAVE_MULTIPATHD HAVE_MODULE SHOW_STATUS CHANGED_CONFIG

DEFAULT_CONFIGFILE="/usr/share/doc/device-mapper-multipath-0.4.9/multipath.conf"
CONFIGFILE="/etc/multipath.conf"
MULTIPATHDIR="/etc/multipath"
TMPFILE=/etc/multipath/.multipath.conf.tmp

function usage
{
	echo "usage: $0 <command>"
	echo ""
	echo "Commands:"
	echo "Enable: --enable "
	echo "Disable: --disable"
	echo "Set user_friendly_names (Default y): --user_friendly_names <y|n>"
	echo "Set find_multipaths (Default y): --find_multipaths <y|n>"
	echo "Load the dm-multipath modules on enable (Default y): --with_module <y|n>"
	echo "start/stop/reload multipathd (Default n): --with_multipathd <y|n>"
	echo ""
}

function parse_args
{
	while [ -n "$1" ]; do
		case $1 in
			--enable)
				ENABLE=1
				shift
				;;
			--disable)
				ENABLE=0
				shift
				;;
			--user_friendly_names)
				if [ -n "$2" ]; then
					FRIENDLY=$2
					shift 2
				else
					usage
					exit 1
				fi
				;;
			--find_multipaths)
				if [ -n "$2" ]; then
					FIND=$2
					shift 2
				else
					usage
					exit 1
				fi
				;;
			--with_module)
				if [ -n "$2" ]; then
					MODULE=$2
					shift 2
				else
					usage
					exit 1
				fi
				;;
			--with_multipathd)
				if [ -n "$2" ]; then
					MULTIPATHD=$2
					shift 2
				else
					usage
					exit 1
				fi
				;;
			*)
				usage
				exit
		esac
	done
}

function validate_args
{
	if [ "$ENABLE" = "0" ] && [ -n "$FRIENDLY" -o -n "$FIND" -o -n "$MODULE" ]; then
		echo "ignoring extra parameters on disable"
		FRIENDLY=""
		FIND=""
		MODULE=""
	fi
	if [ -n "$FRIENDLY" ] && [ "$FRIENDLY" != "y" -a "$FRIENDLY" != "n" ]; then
		echo "--user_friendly_names must be either 'y' or 'n'"
		exit 1
	fi
	if [ -n "$FIND" ] && [ "$FIND" != "y" -a "$FIND" != "n" ]; then
		echo "--find_multipaths must be either 'y' or 'n'"
		exit 1
	fi
	if [ -z "$ENABLE" -a -z "$FIND" -a -z "$FRIENDLY" ]; then
		SHOW_STATUS=1
	fi
	if [ -n "$MODULE" ] && [ "$MODULE" != "y" -a "$MODULE" != "n" ]; then
		echo "--with_module must be either 'y' or 'n'"
		exit 1
	fi
	if [ -n "$MULTIPATHD" ] && [ "$MULTIPATHD" != "y" -a "$MULTIPATHD" != "n" ]; then
		echo "--with_multipathd must be either 'y' or 'n'"
		exit 1
	fi
}

umask 0077

parse_args "$@"

validate_args

if [ ! -d "$MULTIPATHDIR" ]; then
	echo "/etc/multipath/ does not exist. failing"
	exit 1
fi

rm $TMPFILE 2> /dev/null
if [ -f "$CONFIGFILE" ]; then
	cp $CONFIGFILE $TMPFILE
elif [ -f "$DEFAULT_CONFIGFILE" ]; then
	cp $DEFAULT_CONFIGFILE $TMPFILE
else
	touch $TMPFILE
fi

if grep -q "^blacklist[[:space:]]*{" $TMPFILE ; then
	HAVE_BLACKLIST=1
fi

if grep -q "^defaults[[:space:]]*{" $TMPFILE ; then
	HAVE_DEFAULTS=1
fi

if [ -z "$MODULE" -o "$MODULE" = "y" ]; then
	if lsmod | grep -q "dm_multipath" ; then
		HAVE_MODULE=1
	else
		HAVE_MODULE=0
	fi
fi

if [ "$MULTIPATHD" = "y" ]; then
	if /bin/systemctl status multipathd.service > /dev/null 2>&1 ; then
		HAVE_MULTIPATHD=1
	else
		HAVE_MULTIPATHD=0
	fi
fi

if [ "$HAVE_BLACKLIST" = "1" ]; then
	if sed -n '/^blacklist[[:space:]]*{/,/^}/ p' $TMPFILE | grep -q "^[[:space:]]*devnode \"\.\?\*\"" ; then
		HAVE_DISABLE=1
	elif sed -n '/^blacklist[[:space:]]*{/,/^}/ p' $TMPFILE | grep -q "^[[:space:]]*#[#[:space:]]*devnode \"\.\?\*\"" ; then
		HAVE_DISABLE=0
	fi
fi

if [ "$HAVE_DEFAULTS" = "1" ]; then
	if sed -n '/^defaults[[:space:]]*{/,/^}/ p' $TMPFILE | grep -q "^[[:space:]]*find_multipaths[[:space:]]*\(yes\|1\)" ; then
		HAVE_FIND=1
	elif sed -n '/^defaults[[:space:]]*{/,/^}/ p' $TMPFILE | grep -q "^[[:space:]]*find_multipaths[[:space:]]*\(no\|0\)" ; then
		HAVE_FIND=0
	fi
	if sed -n '/^defaults[[:space:]]*{/,/^}/ p' $TMPFILE | grep -q "^[[:space:]]*user_friendly_names[[:space:]]*\(yes\|1\)" ; then
		HAVE_FRIENDLY=1
	elif sed -n '/^defaults[[:space:]]*{/,/^}/ p' $TMPFILE | grep -q "^[[:space:]]*user_friendly_names[[:space:]]*\(no\|0\)" ; then
		HAVE_FRIENDLY=0
	fi
fi

if [ -n "$SHOW_STATUS" ]; then
	if [ -z "$HAVE_DISABLE" -o "$HAVE_DISABLE" = 0 ]; then
		echo "multipath is enabled"
	else
		echo "multipath is disabled"
	fi
	if [ -z "$HAVE_FIND"  -o "$HAVE_FIND" = 0 ]; then
		echo "find_multipaths is disabled"
	else
		echo "find_multipaths is enabled"
	fi
	if [ -z "$HAVE_FRIENDLY" -o "$HAVE_FRIENDLY" = 0 ]; then
		echo "user_friendly_names is disabled"
	else
		echo "user_friendly_names is enabled"
	fi
	if [ -n "$HAVE_MODULE" ]; then
		if [ "$HAVE_MODULE" = 1 ]; then
			echo "dm_multipath module is loaded"
		else
			echo "dm_multipath module is not loaded"
		fi
	fi
	if [ -z "$HAVE_MULTIPATHD" ]; then
		if /bin/systemctl status multipathd.service > /dev/null 2>&1 ; then
			HAVE_MULTIPATHD=1
		else
			HAVE_MULTIPATHD=0
		fi
	fi
	if [ "$HAVE_MULTIPATHD" = 1 ]; then
		echo "multipathd is running"
	else
		echo "multipathd is not running"
	fi
	exit 0
fi

if [ -z "$HAVE_BLACKLIST" ]; then
	cat >> $TMPFILE <<- _EOF_

blacklist {
}
_EOF_
fi

if [ -z "$HAVE_DEFAULTS" ]; then
	cat >> $TMPFILE <<- _EOF_

defaults {
}
_EOF_
fi

if [ "$ENABLE" = 1 ]; then
	if [ "$HAVE_DISABLE" = 1 ]; then
		sed -i '/^blacklist[[:space:]]*{/,/^}/ s/^[[:space:]]*devnode \"\.\?\*\"/#	devnode ".*"/' $TMPFILE
	fi
elif [ "$ENABLE" = 0 ]; then
	if [ -z "$HAVE_DISABLE" ]; then
		sed -i '/^blacklist[[:space:]]*{/ a\
	devnode "*"
' $TMPFILE
	elif [ "$HAVE_DISABLE" = 0 ]; then
		sed -i '/^blacklist[[:space:]]*{/,/^}/ s/^[[:space:]]*#[#[:space:]]*devnode \"\.\?\*\"/	devnode ".*"/' $TMPFILE
	fi
fi

if [ "$FIND" = "n" ]; then
	if [ "$HAVE_FIND" = 1 ]; then
		sed -i '/^defaults[[:space:]]*{/,/^}/ s/^[[:space:]]*find_multipaths[[:space:]]*\(yes\|1\)/	find_multipaths no/' $TMPFILE
		CHANGED_CONFIG=1
	fi
elif [ "$FIND" = "y" ]; then
	if [ -z "$HAVE_FIND" ]; then
		sed -i '/^defaults[[:space:]]*{/ a\
	find_multipaths yes
' $TMPFILE
		CHANGED_CONFIG=1
	elif [ "$HAVE_FIND" = 0 ]; then
		sed -i '/^defaults[[:space:]]*{/,/^}/ s/^[[:space:]]*find_multipaths[[:space:]]*\(no\|0\)/	find_multipaths yes/' $TMPFILE
		CHANGED_CONFIG=1
	fi
fi

if [ "$FRIENDLY" = "n" ]; then
	if [ "$HAVE_FRIENDLY" = 1 ]; then
		sed -i '/^defaults[[:space:]]*{/,/^}/ s/^[[:space:]]*user_friendly_names[[:space:]]*\(yes\|1\)/	user_friendly_names no/' $TMPFILE
		CHANGED_CONFIG=1
	fi
elif [ "$FRIENDLY" = "y" ]; then
	if [ -z "$HAVE_FRIENDLY" ]; then
		sed -i '/^defaults[[:space:]]*{/ a\
	user_friendly_names yes
' $TMPFILE
		CHANGED_CONFIG=1
	elif [ "$HAVE_FRIENDLY" = 0 ]; then
		sed -i '/^defaults[[:space:]]*{/,/^}/ s/^[[:space:]]*user_friendly_names[[:space:]]*\(no\|0\)/	user_friendly_names yes/' $TMPFILE
		CHANGED_CONFIG=1
	fi
fi

if [ -f "$CONFIGFILE" ]; then
	cp $CONFIGFILE $CONFIGFILE.old
	if [ $? != 0 ]; then
		echo "failed to backup old config file, $CONFIGFILE not updated"
		exit 1
	fi
fi

cp $TMPFILE $CONFIGFILE
if [ $? != 0 ]; then
	echo "failed to copy new config file into place, check $CONFIGFILE is still OK"
	exit 1
fi

rm -f $TMPFILE

if [ "$ENABLE" = 1 ]; then
	if [ "$HAVE_MODULE" = 0 ]; then
		modprobe dm_multipath
	fi
	if [ "$HAVE_MULTIPATHD" = 0 ]; then
		systemctl start multipathd.service
	fi
elif [ "$ENABLE" = 0 ]; then
	if [ "$HAVE_MULTIPATHD" = 1 ]; then
		systemctl stop multipathd.service
	fi
elif [ -n "$CHANGED_CONFIG" -a "$HAVE_MULTIPATHD" = 1 ]; then
	systemctl reload multipathd.service
fi