#!/bin/bash
#
# $Id: modified-iso-install,v 1.3 2008/05/17 07:00:42 suter Exp $
# Copyright (C) 2003 Mark Suter <mark.suter@miju.com.au>
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

## Our "die" function (think perl)
function die () { echo "$@" 1>&2 ; exit 1 ; }

## Test for needed binaries
hash test perl date cat sfdisk mkfs mkswap mkdir mount umount gzip cpio chmod sync chroot || die $0: required binaries not present

## Record our starting time
start=$( date +%s )

## Find the first disk
disk=$( perl -ne 'm{ [hs] d [a-z] $ }x and print $& and exit' /proc/partitions )

## Are you sure?
test "$( id -u )" == "0" || die $0: script must be run as root
cat <<EOF 1>&2
#################################################################

This script will repartition /dev/$disk and install a base system.
You will lose all existing data on that hard disk drive.

Enter "Execute" at the prompt below to proceed.
EOF
while [ "${resp}" != "Execute" ] ; do
    read -p "? " resp
done
cat <<EOF 1>&2

Proceeding with installation...

#################################################################
EOF

## Exit on any error, display the commands
set -x -e

## Partition the disk, according to size
gib=$( grep ${disk}\$ /proc/partitions | perl -ane 'print int $F[2] / 2** 20' )
if [ $gib -ge 20 ] ; then
    echo -e "0,5120\n,2048,S\n,10240\n;" | sfdisk -uM /dev/$disk || die $0: partitioning failed
elif [ $gib -ge 10 ] ; then
    echo -e "0,2048\n,1024,S\n,3072\n;" | sfdisk -uM /dev/$disk || die $0: partitioning failed
elif [ $gib -ge 5 ] ; then
    echo -e "0,1024\n,1024,S\n,1536\n;" | sfdisk -uM /dev/$disk || die $0: partitioning failed
else
    die $0: first disk seems too small at approx $gib GiB - try manually installing
fi

## Make the filesystems
mkfs -t ext3 -L root -O filetype /dev/${disk}1
mkswap /dev/${disk}2
mkfs -t ext3 -L var  -O filetype /dev/${disk}3
mkfs -t ext3 -L home -O filetype /dev/${disk}4

## Mount the new system
mkdir -p /ebbe
mount /dev/${disk}1 /ebbe
mkdir -p /ebbe/{var,home}
mount /dev/${disk}3 /ebbe/var
mount /dev/${disk}4 /ebbe/home

## Copy the files over (or from an existing server using ssh?)
# ( cd /ebbe ; ssh XXX cd / \; find . -print0 \| cpio --null --format=crc --create | cpio --make-directories --preserve-modification-time --extract )
( cd /ebbe ; gzip -dc /mnt/cdrom/ebbe.cpio.gz | cpio --make-directories --preserve-modification-time --extract )

## Make the system bootable (chroot to avoid library problems)
sync ; sync ; sync
chroot /ebbe /usr/sbin/grub --batch --device-map=/dev/null <<EOF || die $0: grub failed.
device (hd0) /dev/$disk
root (hd0,0)
setup (hd0)
quit
EOF

## Umount and then remount
umount /ebbe/home
umount /ebbe/var
umount /ebbe
mount -o ro /dev/${disk}1 /ebbe
mount -o ro /dev/${disk}3 /ebbe/var
mount -o ro /dev/${disk}4 /ebbe/home

## Let our admin know what's happened
elapsed=$(( $(date +%s) - $start ))
cat <<EOF 1>&2

#################################################################

Done in ${elapsed}s with the newly prepared system now under
/ebbe for you to examine, then reboot and remove the cd.

#################################################################

EOF