#!/bin/sh
#
# ramdisk         This shell script takes care of starting and stopping
#                 the ramdisks.
#
# chkconfig: 345 00 99
# description: ramdisk caches /etc and /var to two ramdisks and mounts \
# them to avoid disk accesses to save power.

# Source function library.
. /etc/rc.d/init.d/functions

if [ $0 != "/tmp/ramdisk" ] ; then
	cp $0 /tmp/ramdisk
	exec /tmp/ramdisk $1
fi

[ -f /etc/useramdisk ] || exit 0

# See how we were called.
case "$1" in
  start)
        # Start daemons.
        echo -n "Starting ramdisk: "

	mkdir -p /mnt/ram /mnt/ram2
	
	# Fix /etc/conf.modules
	RD_SIZE=`egrep "options rd.*rd_size" /etc/conf.modules | sed "s/^options rd.*rd_size=0*\([^ ]*\).*$/\1/"`
	if [ $(($RD_SIZE)) -lt 18432 ] ; then
		cp -f /etc/conf.modules /etc/conf.modules~
		TEST1=`grep "options rd" /etc/conf.modules~`
		TEST2=`echo $TEST1 | grep "rd_size"`
		if [ -z "$TEST1" ] ; then
			echo >> /etc/conf.modules	
			echo options rd rd_size=18432 >> /etc/conf.modules
		elif [ -z "$TEST2" ] ; then
			sed "s/^options rd\(.*\)/options rd\1 rd_size=18432/" /etc/conf.modules~ > /etc/conf.modules
		else
			sed "s/^options rd\(.*\)rd_size=[^ ]*\(.*\)/options rd\1rd_size=18432\2/" /etc/conf.modules~ > /etc/conf.modules
		fi
	fi

	# Make ramdisks
	if ! grep /etc /proc/mounts > /dev/null ; then
		dd if=/dev/zero of=/dev/ram bs=1k count=8192 > /dev/null 2>&1
		mke2fs -qm0 /dev/ram 8192 > /dev/null 2>&1
		ETCDIR=/etc

		if mount /dev/ram /mnt/ram ; then
			if [ -d /etc.saveme ] ; then
				ETCDIR=/etc.saveme
			fi
	
			if cp -dpfR /$ETCDIR/* /mnt/ram ; then
				umount /dev/ram
				mount /dev/ram /etc
				cat /proc/mounts > /etc/mtab
				rm -f /etc/mtab~
				if [ -d /etc.saveme ] ; then
					rm -rf /etc.saveme
				fi
			else
				umount /dev/ram
			fi
		fi
	fi

	if ! grep /var /proc/mounts > /dev/null ; then	
		dd if=/dev/zero of=/dev/ram2 bs=1k count=18432 > /dev/null 2>&1
		mke2fs -qm0 /dev/ram2 18432 > /dev/null 2>&1 
		VARDIR=/var

		if mount /dev/ram2 /mnt/ram2 ; then
			if [ -d /var.saveme ] ; then
				VARDIR=/var.saveme
			fi

			if cp -dpfR /$VARDIR/* /mnt/ram2 ; then
				umount /dev/ram2
				mount /dev/ram2 /var
				if [ -d /var.saveme ] ; then
					rm -rf /var.saveme
				fi
			else
				umount /dev/ram2
			fi
		fi
	fi

	hdparm -S5 /dev/hda > /dev/null

	success "ramdisk startup"
        touch /var/lock/subsys/ramdisk
	echo 
        ;;
  stop)
        # Stop daemons.
        echo -n "Shutting down ramdisk: "

	mkdir -p /mnt/ram /mnt/ram2 

	if grep /etc /proc/mounts > /dev/null ; then
		if umount /etc 2> /dev/null ; then
			mount -r /dev/ram /mnt/ram
			mkdir -p /etc.new
			if cp -dpfR /mnt/ram/* /etc.new ; then
				rm -rf /etc.old
				mv -f /etc /etc.old
				mv -f /etc.new /etc
			fi
			umount /dev/ram
			cat /proc/mounts > /etc/mtab
			rm -f /etc/mtab~
		else 			# Uh-oh... try to save it...
			echo Filesystem busy, trying to recover...
			mkdir -p /etc.saveme
			cp -dpfR /etc/* /etc.saveme
		fi
	fi

	if grep /var /proc/mounts > /dev/null ; then
		if umount /var 2> /dev/null ; then
			mount -r /dev/ram2 /mnt/ram2
			mkdir -p /var.new
			if cp -dpfR /mnt/ram2/* /var.new ; then
				rm -rf /var.old
				mv -f /var /var.old
				mv -f /var.new /var
			fi
			umount /dev/ram2
		else 			# Uh-oh... try to save it...
			echo Filesystem busy, trying to recover...
			mkdir -p /var.saveme
			cp -dpfR /var/* /var.saveme
		fi
	fi
	success "ramdisk shutdown"
        rm -f /var/lock/subsys/ramdisk
        echo
        ;;
  status)
	status ramdisk
	exit $?
	;;
  restart)
	$0 stop
	$1 start
	exit $?
	;;
  *)
        echo "Usage: ramdisk {start|stop|status|restart}"
        exit 1
esac

exit 0