#!/bin/bash

cleanup() {
    [ -d "$DISKMOUNT" ] && { umount $DISKMOUNT; rmdir $DISKMOUNT; }
    [ -d "$SQUASHMNT" ] && { umount $SQUASHMNT; rmdir $SQUASHMNT; }
    [ -d "$ISOMNT" ] && { umount $ISOMNT; rmdir $ISOMNT; }
    [ -d "$ROOT" ] && { umount $ROOT; rmdir $ROOT; }
}

exitclean() {
    echo "Cleaning up to exit..."
    cleanup
    exit 1
}

trap exitclean SIGINT SIGTERM

ISO=$(readlink -f "$1")
IMG=$(readlink -f "$2")

ISOMNT=$(mktemp -d /media/isotmp.XXXXXX)
mount -o loop,ro "$ISO" $ISOMNT || exitclean
SQUASHMNT=$(mktemp -d /media/squashtmp.XXXXXX)
mount -o loop,ro $ISOMNT/LiveOS/squashfs.img $SQUASHMNT || exitclean
DISKMOUNT=$(mktemp -d /media/disktmp.XXXXXX)
mount -o loop,ro $SQUASHMNT/LiveOS/ext3fs.img $DISKMOUNT || exitclean

echo "Create root filesystem..."
ROOT=$(mktemp -d /tmp/root.XXXXXX)

dd if=/dev/zero of=$IMG bs=1 count=1 seek=4G || exitclean
mke2fs -O dir_index -F $IMG || exitclean
mount -o loop $IMG $ROOT || exitclean

cp -a $DISKMOUNT/* $ROOT
cp $ISOMNT/isolinux/initrd0.img $ROOT/boot
cp $ISOMNT/isolinux/vmlinuz0 $ROOT/boot

if [ ! -e $ROOT/boot/olpc.fth ] ; then
    echo "no $ROOT/boot/olpc.fth - should have been added by whatever installed $ROOT/boot/vmlinuz*"
    exit 1;
fi

sed -i -e 's/rootfstype=jffs2/rootfstype=ext4/' $ROOT/boot/olpc.fth

echo "Done."
cleanup