disk size in pre script?

[Ryan Lovett]

Is it possible to fetch the size of the disk in the pre script?
list-devices and udevinfo return empty values. (maybe because /dev hasn't
been set up yet?)

  FIRSTDISK="$(list-devices disk | head -n1)"
  UDEV_PATH="$(udevinfo -q path -n ${FIRSTDISK})"
  SIZE=$(udevinfo -a -p ${UDEV_PATH} | grep size | sed -e 's/"$//' -e 's/.*"//')
  SIZEGB=$(( ${SIZE} * 512 / 1000000000 ))

I'm trying to dynamically set the series of 'part' commands based on disk
size. e.g.

if [ $SIZEGB -gt 100 ]; then
    cat <<EOF > /tmp/part-include.cfg
part ...
part ...
EOF
elif [ $SIZEGB -gt 80 ]; then
    ...
fi

...

%include /tmp/part-include.cfg

etc. I know about part's --grow option, but I'd like more flexibility.

Ryan