#!/bin/sh

# ****  DO NOT EVEN THINK OF EDITING OR REMOVING THIS FILE  ****
# **** UNLESS YOU REALLY KNOW *EXACTLY* WHAT YOU ARE DOING. ****


# Determine the desired rootfs based on user flag files.

if [ -f /.ramdisk ] ; then
    /bin/echo "Preferred root device is /dev/ram0 (maintenence)"
    mounted=/mnt
    prefroot=maintenence
elif [ -f /.sda1root ] ; then
    /bin/echo "Preferred root device is /dev/sda1 (disk 1)"
    mounted=/mnt
    prefroot=sda1
elif [ -f /.sda2root ] ; then
    /bin/echo "Preferred root device is /dev/sda2 (disk 1)"
    mounted=/mnt
    prefroot=sda2
elif [ -f /.sdb1root ] ; then
    /bin/echo "Preferred root device is /dev/sdb1 (disk 2)"
    mounted=/mnt
    prefroot=sdb1
elif [ -f /.sdb2root ] ; then
    /bin/echo "Preferred root device is /dev/sdb2 (disk 2)"
    mounted=/mnt
    prefroot=sdb2
elif [ -f /.nfsroot ] ; then
    /bin/echo "Preferred root device is NFS"
    mounted=/mnt
    prefroot=nfsroot
else
    /bin/echo "Preferred root device is jffs2"
    mounted=
    prefroot=jffs2
fi


# Perform prepatory tasks, and determine whether the desired rootfs is viable.

/bin/mount -t proc proc /proc

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
    if [ -L /mnt/sbin/init -o -x /mnt/sbin/init -o \
	-L /mnt/bin/init  -o -x /mnt/bin/init ] ; then
	/bin/echo "Root filesystem will be mounted from /dev/$prefroot ..."
    else
	/bin/umount /mnt
	/bin/echo "Can't find valid rootfs on /dev/$prefroot, using jffs2 ..."
	mounted=
	prefroot=jffs2
    fi
fi

if [ $prefroot = "maintenence" ] ; then
    /bin/dd if=/dev/zero of=/dev/ram0 bs=1k count=12k 2>/dev/null 
    /usr/bin/mke2fs -m 0 /dev/ram0 12288
    /bin/mount -t ext2 /dev/ram0 /mnt
    ( /usr/bin/find . -print0 -mount | /usr/bin/cpio -p -0 -d -m -u /mnt )
    /bin/rm -f /mnt/linuxrc
    /bin/mkdir /mnt/mnt/backup /mnt/mnt/repair /mnt/mnt/tmpmnt
fi

if [ $prefroot = "nfsroot" ] ; then

    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=//`

    /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.
    . /.nfsroot

    /bin/mount $nfsrootopts $nfsrootloc /mnt

    if  [ -L /mnt/sbin/init -o -x /mnt/sbin/init -o \
	-L /mnt/bin/init  -o -x /mnt/bin/init ] ; then
	/bin/echo "Root filesystem will be mounted from an NFS root ..."
	mounted=/mnt
    else
	/bin/umount /mnt
	/bin/echo "Can't find valid NFS rootfs, using jffs2 ..."
	mounted=
	prefroot=jffs2
    fi
fi

if [ $prefroot = "jffs2" ] ; then
    /bin/echo "Root filesystem will be mounted from /dev/mtdblock4 ..."
    mounted=
fi


/bin/umount /proc

# Pivot to the desired rootfs and run the initial executable.

if [ -n "$mounted" ] ; then

    cd $mounted

    if [ -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

else

    exec /bin/init

fi

/bin/echo "Can't chroot to $prefroot, using jffs2 ..."
exec /bin/init

# Last-resort fall-back - this should never be reached.
/bin/sh