source: freewrt/package/base-files/default/bin/firstboot@ e4ba301

#!/bin/sh
# $Id: firstboot 3633 2006-04-13 14:43:47Z nbd $

rom=$(awk '/squashfs/ {print $2}' /proc/mounts)
jffs=$(awk '/jffs2/ {print $2}' /proc/mounts)

dupe() { # <new_root> <old_root>
        cd $1
        echo -n "creating directories... "
        {
                cd $2 
                find . -xdev -type d
                echo "./dev ./jffs ./mnt ./proc ./tmp ./sys"
                # xdev skips mounted directories
                cd $1 
        } | xargs mkdir -p
        echo "done"

        echo -n "setting up symlinks... "
        for file in $(cd $2; find . -xdev -type f;); do
                case "$file" in
                ./rom/note) ;; #nothing
                ./etc/config*|\
                ./etc/resolv.conf|\
                ./usr/lib/ipkg/info) cp -af $2/$file $file;;
                *) ln -sf /rom/${file#./*} $file;;
                esac
        done
        for file in $(cd $2; find . -xdev -type l;); do
                cp -af $2/${file#./*} $file
        done
        echo "done"
}

pivot() { # <new_root> <old_root>
        mount -o move /proc $1/proc && \
        pivot_root $1 $1$2 && {
                mount -o move $2/dev /dev
                mount -o move $2/tmp /tmp
                mount -o move $2/sys /sys
                return 0
        }
}

mountdp() { # <device> <mount_point> <ignored> <fs>
        dev=$1; mnt=$2; shift 2; opt=$*
        mount $dev $mnt $opt
        dupe $mnt $rom
        pivot $mnt /rom
}

fopivot() { # <rw_root> <ro_root> <dupe?>
        root=$1
    {
      mount -t mini_fo -o base=/,sto=$1 $1 /mnt 2>&- && root=/mnt
    } || {
      [ "$3" = "1" ] && mount -o bind $1 $1 && dupe $1 $rom
    }
    pivot $root $2
}


ramoverlay() {
        mkdir -p /tmp/root
        mountdp /tmp/root /mnt -o bind
}

[ "${0##*/}" = "firstboot" ] && {
        [ -z "$rom" ] && {
                echo "You do not have a squashfs partition; aborting"
                echo "(firstboot cannot be run on jffs2 based firmwares)"
                exit 1
        }

        [ "$1" = "switch2jffs" ] && {
                mtd erase data
                mount -o remount,ro none / # try to avoid fs changing while copying
                mount -o bind / /mnt
                mount /dev/mtdblock/4 /rom/jffs -t jffs2
                echo -n "copying files ... "
                cp -a /mnt/* /rom/jffs
                umount /mnt
                echo "done"
                pivot /rom /mnt
                mount -o move /mnt /tmp/root
                pivot /jffs /rom
                jffs2root --clean
                exit 0
        }

        # script run manually
        [ \! -z "$jffs" ] && {
                echo "firstboot has already been run"
                echo "jffs2 partition is mounted, only resetting files"
                dupe $jffs $rom
                exit 0
        }

        mtd erase data
        mountdp /dev/mtdblock/4 /jffs -t jffs2
}