build_diskimage.sh

#! /bin/sh 

if [ -z "$TOPDIR" ] ; then
  echo "you must define TOPDIR"
  exit
fi

WHAT="$1"
if [ -z "$WHAT" ] ; then

    echo "building 32 and 64 bit images" 
    WHAT="32 64"
fi

. $TOPDIR/settings.sh

# in case the loop device doesn't exist, we try to load the module
if ! [ -b $LOOP ] ; then
    modprobe loop 
    sleep 5
fi

# if it still doesn't exist, we stop here before we cause damage
if ! [ -b $LOOP ] ; then
    echo "$LOOP doesn't seem to exist - please check!"
    exit 1
fi

oldpwd=`pwd`
for version in $WHAT
	do
		echo -n "Creating the $version bit system Ramdisk image.... "
		IMAGE=$TOPDIR/cdtree/isolinux/sdisk${version}.img 
		echo "Initial Ramdisk contents will be $ISIZE KB"

# delete the existing ramdisk image, if there is one
		rm -f $IMAGE
		REALSIZE=$ISIZE

# create a file of REALSIZE 
		dd if=/dev/zero of=$TOPDIR/sdisk bs=1k count=$REALSIZE

# associate it with ${LOOP}
		losetup ${LOOP} $TOPDIR/sdisk

# make an ext2 filesystem on it. We set the amount of unused space to 0%
# and turn down the number of inodes to save space. Note that we
# use the 4KB smaller ISIZE, for reiserfs compatibility.
		mke2fs -q -i 16384 -m 0 ${LOOP} $ISIZE

# make sure we have $TOPDIR/loop2
		[ -d  $TOPDIR/loop2 ] || mkdir  $TOPDIR/loop2 
# we mount it...
		mount ${LOOP} $TOPDIR/loop2 
# ... and delete the lost+found directory 
		rm -rf $TOPDIR/loop2/lost+found 
# then we copy the contents of our initrdtree to this filesystem
		pushd $TOPDIR/loop2/
			tar -xvpf $TOPDIR/root_tree${version}.tar.xz
			cp $TOPDIR/hostkeys/* etc/ssh
			cp -r $TOPDIR/xtras${version}/* . ||true
			cp -r $TOPDIR/xtrasanyarch/* . ||true
		popd

		df  $TOPDIR/loop2

# and unmount and divorce ${LOOP}
		umount $TOPDIR/loop2
		losetup -d ${LOOP} 
# Now we have the image of the initial ramdisk in $TOPDIR/loopfiles/ramdisk. We
# compress this one and write the compressed image to the boot tree:
		echo -n "Compressing the $version bit System Ramdisk image.... "
# delete any existing one
		rm -f $IMAGE
# and gzip our initial ramdisk image and put it in the right place.
#gzip -9 -c $TOPDIR/sdisk > $IMAGE
		bzip2 -c $TOPDIR/sdisk > $IMAGE
		echo
		rm -f $TOPDIR/sdisk
	done

echo "done"