#!/bin/sh

mounted=
prefroot=
runboot=

/bin/mount -t proc proc /proc

sysconflen=`/bin/dd if=/dev/mtd1 bs=4 count=1 2>/dev/null | /usr/bin/hexdump -n 6 -e '"%02d"'`
ipaddr=`/bin/dd if=/dev/mtd1 bs=1 count=$sysconflen skip=4 2>/dev/null | grep ip_addr | sed -e s/ip_addr=//`
netmask=`/bin/dd if=/dev/mtd1 bs=1 count=$sysconflen skip=4 2>/dev/null | grep netmask | sed -e s/netmask=//`
gateway=`/bin/dd if=/dev/mtd1 bs=1 count=$sysconflen skip=4 2>/dev/null | grep gateway | sed -e s/gateway=//`
device=/dev/`/bin/sed -n -e 's/^\(mtd[0-9]*\): .* "FIS directory"/\1/p' /proc/mtd`   
length=`/bin/dd if=$device bs=2 skip=2048 2>/dev/null | /usr/bin/hexdump -n 4 -e '4/1 "%02X"' $device`

# Determine desired rootfs
if [ -z "$mounted" ] && /bin/mount -rt jffs2 /dev/mtdblock4 /mnt/jffs2 ; then
    if [ -f /mnt/jffs2/.recovery ] ; then
	/bin/echo "Preferred root device is /dev/ram0 (recovery)"
	mounted=
	prefroot=
    elif [ -f /mnt/jffs2/.ramdisk ] ; then
	/bin/echo "Preferred root device is /dev/ram1 (maintenence)"
	mounted=/mnt/newroot
	prefroot=maintenence
    elif [ -f /mnt/jffs2/.sda1root ] ; then
	/bin/echo "Preferred root device is /dev/sda1 (disk 1)"
	mounted=/mnt/newroot
	prefroot=sda1
    elif [ -f /mnt/jffs2/.sda2root ] ; then
	/bin/echo "Preferred root device is /dev/sda2 (disk 1)"
	mounted=/mnt/newroot
	prefroot=sda2
    elif [ -f /mnt/jffs2/.sdb1root ] ; then
	/bin/echo "Preferred root device is /dev/sdb1 (disk 2)"
	mounted=/mnt/newroot
	prefroot=sdb1
    elif [ -f /mnt/jffs2/.sdb2root ] ; then
	/bin/echo "Preferred root device is /dev/sdb2 (disk 2)"
	mounted=/mnt/newroot
	prefroot=sdb2
    elif [ -f /mnt/jffs2/.altroot ] ; then
	/bin/echo "Preferred root device is a user defined blockdevice"
	mounted=/mnt/newroot
	prefroot=altroot
    elif [ -f /mnt/jffs2/.nfsroot ] ; then
	/bin/echo "Preferred root device is through NFS"
        mounted=/mnt/newroot
	prefroot=nfsroot
    else
	/bin/echo "Preferred root device is jffs2"
	mounted=/mnt/jffs2
	prefroot=jffs2
    fi
fi

# perform prepatory tasks
if [ -n "$prefroot" ] ; then

    if [ $prefroot = "sda1" -o $prefroot = "sda2" -o $prefroot = "sdb1" -o $prefroot = "sdb2" ] ; then
	/bin/echo "Sleeping 10sec while waiting for disk..."
	sleep 10
        /bin/mount -rt ext3 /dev/$prefroot /mnt/newroot
	if [ -L /mnt/newroot/sbin/init -o -x /mnt/newroot/sbin/init -o \
	     -L /mnt/newroot/bin/init  -o -x /mnt/newroot/bin/init ] ; then
	    /bin/echo "Root filesystem will be mounted from /dev/$prefroot ..."
	else
	    /bin/umount /mnt/newroot
	    /bin/echo "Cant find valid rootfs on /dev/$prefroot, using jffs2 ..."
	    mounted=/mnt/jffs2
	    prefroot=jffs2
	fi

    fi

    if [ $prefroot = "maintenence" ] ; then
        /bin/dd if=/dev/zero of=/dev/ram1 bs=1k count=12k 2>/dev/null 
        /bin/mkdir /lib
        /bin/ln -s /mnt/jffs2/lib/* /lib
        /bin/mkdir -p /usr/bin
        /bin/ln -s /mnt/jffs2/usr/bin/mke2fs /usr/bin
        /bin/ln -s /mnt/jffs2/usr/bin/find /usr/bin
        /bin/ln -s /mnt/jffs2/usr/bin/cpio /usr/bin
        /usr/bin/mke2fs -m 0 /dev/ram1 12288
        /bin/mount -t ext2 /dev/ram1 /mnt/newroot
        ( cd /mnt/jffs2 ; /usr/bin/find . -print0 -mount | /usr/bin/cpio -p -0 -d -m -u /mnt/newroot )
	if [ -r /mnt/newroot/.unslung ] ; then
            /bin/cp /mnt/newroot/home/httpd/html/Management/upgrade.cgi /mnt/newroot/home/httpd/html/Management/upgrade-real.cgi
            /bin/echo "#!/bin/sh" > /mnt/newroot/home/httpd/html/Management/upgrade.cgi
            /bin/echo >> /mnt/newroot/home/httpd/html/Management/upgrade.cgi
            /bin/echo "/bin/mount -t ramfs none /upload -o size=8196 2>/dev/null" \
                >> /mnt/newroot/home/httpd/html/Management/upgrade.cgi
            /bin/echo "/bin/dd if=/dev/zero of=/upload/free-ram bs=1k count=8k 2>/dev/null" \
                >> /mnt/newroot/home/httpd/html/Management/upgrade.cgi
            /bin/echo "/bin/umount /upload 2>/dev/null" \
                >> /mnt/newroot/home/httpd/html/Management/upgrade.cgi
            /bin/echo "exec /home/httpd/html/Management/upgrade-real.cgi" \
                >> /mnt/newroot/home/httpd/html/Management/upgrade.cgi
            /bin/echo "Root filesystem will be mounted from /dev/ram1 (a copy of /dev/mtdblock4) ..."
	elif [ -r /mnt/newroot/.openslug ] ; then
            /bin/echo "Root filesystem will be mounted from /dev/ram1 (a copy of /dev/mtdblock4) ..."
	else
	    /bin/umount /mnt/newroot
	    /bin/echo "Cant find valid rootfs on /dev/ram1, using recovery ..."
	    mounted=
	    prefroot=
	fi

    fi

    if [ $prefroot = "altroot" ] ; then
        # The altrootloc and altrootopts vars MUST be chosen here.
	# ie: $altrootopts="-rt ext3" and $altrootloc=/dev/md0
	# Also modules can be loaded here.
	# also if you have a really slow starting disk, you can put a large sleep value here.
        . /mnt/jffs2/.altroot

        /bin/mount $altrootopts $altrootloc /mnt/newroot
	if [ -L /mnt/newroot/sbin/init -o -x /mnt/newroot/sbin/init -o \
	     -L /mnt/newroot/bin/init  -o -x /mnt/newroot/bin/init ] ; then
	    /bin/echo "Root filesystem will be mounted from a user defined rootfs (altroot) ..."
	else
	    /bin/umount /mnt/newroot
	    /bin/echo "Cant find valid rootfs on user defined rootfs (altroot), using jffs2 ..."
	    mounted=/mnt/jffs2
	    prefroot=jffs2
	fi
    fi

    if [ $prefroot = "nfsroot" ] ; then

	/sbin/insmod ixp400
	/sbin/insmod ixp425_eth
	/sbin/ifconfig ixp0 up $ipaddr netmask $netmask
	/sbin/route add default gw $gateway

	/sbin/ifconfig lo up 127.0.0.1

	# The nfsrootloc and nfsrootopts vars can be overridden here.
	. /mnt/jffs2/.nfsroot

	/bin/mount $nfsrootopts $nfsrootloc /mnt/newroot

    	if  [ -L /mnt/newroot/sbin/init -o -x /mnt/newroot/sbin/init -o \
	      -L /mnt/newroot/bin/init  -o -x /mnt/newroot/bin/init ] ; then
	    /bin/echo "Root filesystem will be mounted from an NFS root ..."
	    mounted=/mnt/newroot
	else
	    /bin/umount /mnt/newroot
	    /bin/echo "Cant find valid NFS rootfs, using jffs2 ..."
	    mounted=/mnt/jffs2
	    prefroot=jffs2
	fi

    fi

    if [ $prefroot = "jffs2" ] ; then
    	if  [ -L /mnt/jffs2/sbin/init -o -x /mnt/jffs2/sbin/init -o \
	      -L /mnt/jffs2/bin/init  -o -x /mnt/jffs2/bin/init ] ; then
	    /bin/echo "Root filesystem will be mounted from /dev/mtdblock4 ..."
	    mounted=/mnt/jffs2
	else
	    /bin/echo "Cant find valid rootfs on jffs2, using recovery ..."
	    mounted=
	fi
    fi
fi

# Pivot
if [ -n "$mounted" ] ; then
    if [ $mounted != "/mnt/jffs2" ] ; then
        sleep 1
        /bin/umount /mnt/jffs2
    fi
    /bin/umount /proc
    cd $mounted
    if [ -x ./linuxrc -o -L ./linuxrc ] ; then
	runboot=/linuxrc
    elif [ -x ./sbin/init -o -L ./sbin/init ] ; then
	runboot=/sbin/init
    elif [ -x ./bin/init -o -L ./bin/init ] ; then
	runboot=/bin/init
    else
	runboot=/bin/sh
    fi
    /sbin/pivot_root . initrd
    exec /usr/sbin/chroot . $runboot < /dev/console 1> /dev/console 2> /dev/console
fi

if [ -z "$mounted" ] ; then
    /bin/echo "Root filesystem cannot be found - dropping into shell ..."

    if ( [ -x /sbin/telnetd -a "$length" != "FFFFFFFF" ] ); then
	/bin/dd if=$device bs=2 skip=2056 2>/dev/null | /bin/tar zxvf -
	/sbin/insmod ixp400
	/sbin/insmod ixp425_eth
       	/sbin/ifconfig ixp0 up $ipaddr netmask $netmask
	/sbin/telnetd
    fi

    exec /bin/sh
fi

/bin/umount /proc

exit 0