#!/bin/bash
# 
# Copyright 2011 by Bdale Garbee <bdale@gag.com>
# 
# 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 3 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, see <http://www.gnu.org/licenses/>.
# 

# based on work by <ivan@sanchezortega.es>, who released his script under
# the following license terms:
#  ----------------------------------------------------------------------------
#  "THE BEER-WARE LICENSE" (Revision 42):
#  As long as you retain this notice you can do whatever you want with 
#  this stuff. If we meet some day, and you think this stuff is worth it, 
#  you can buy me a beer in return.
#  ----------------------------------------------------------------------------

# mk_dreamplug_rootfs
#
# Runs multistrap and readies the resulting root filesystem to silently 
# complete package configuration on the first boot-up.

# where to build images, etc
basedir=`pwd`/build
target=$basedir/dreamplug
tmpdir=$basedir/tmp
pkgcache=$tmpdir/aptcache

mkdir -p $target
mkdir -p $tmpdir
mkdir -p $pkgcache

hostname='freedombox'
rootpassword='freedom'

kernelimage=http://www.newit.co.uk/kernels/Dreamplug/Dreamplug-prerelease/uImage
kernelmodules=http://www.newit.co.uk/kernels/Dreamplug/Dreamplug-prerelease/Modules.tar.gz

if [ ! -f $tmpdir/uImage ]
then
	wget -c $kernelimage --output-document="$tmpdir/uImage"
fi
if [ ! -f $tmpdir/linux.tar.gz ]
then
	wget -c $kernelmodules --output-document="$tmpdir/linux.tar.gz"
fi

rm -rf $target/*

mkdir -p $target/var/cache/apt/ && mount -o bind $pkgcache $target/var/cache/apt/

echo "Multistrapping..."
multistrap -f fbx-armel.conf --no-auth -d $target 

umount $target/var/cache/apt/
mkdir $target/var/cache/apt/archives

echo "Unpacking kernel modules..."
mkdir -p $target/lib/modules/
tar -C $target/lib/ -zxvf $tmpdir/linux.tar.gz | tail

echo "copy uImage to target filesystem"
mkdir -p $target/boot
cp build/tmp/uImage $target/boot/uImage
echo "copy copy2dream.sh script to target filesystem"
cp bin/copy2dream.sh $target/boot/copy2dream.sh

# Until udev is configured and run for the first time, dev nodes won't be created, but we need some basic ones for spawning a console (console) and creating RSA keys for SSH (urandom).
echo "Creating basic device nodes"
mknod $target/dev/console c 5 1
mknod $target/dev/random c 1 8
mknod $target/dev/urandom c 1 9
mknod $target/dev/null c 1 3
mknod $target/dev/ptmx c 5 2

# Basic fstab & mtab..
echo "Setting up basic fstab & mtab"
echo "
rootfs	/		rootfs	relatime,rw	0	0
proc	/proc		proc	none		0	0
sys	/sys		sysfs	none		0	0
none	/dev/pts	devpts	defaults	0	0
tmpfs   /tmp            tmpfs   rw,nosuid,nodev 0       0
" > $target/etc/fstab

touch $target/etc/mtab

# Set up hostname
echo "Setting up hostname, /etc/network/interfaces, nameservers, persistent-net-generator rules"
echo $hostname > $target/etc/hostname

# Create /etc/network/interfaces
echo "# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).

# The loopback network interface
auto lo
iface lo inet loopback

# The primary network interface
allow-hotplug eth0
iface eth0 inet dhcp

allow-hotplug eth1
iface eth1 inet dhcp
        " > $target/etc/network/interfaces

# Setup nameserver (use OpenDNS by default)
echo "nameserver 208.67.222.222
nameserver 208.67.220.220" > $target/etc/resolv.conf

# Touch the net generator udev so that eth0 won't be reassigned in case the user
# changes the MAC address - this may happen if you change the rootfs between plugs.
touch $target/etc/udev/rules.d/75-persistent-net-generator.rules

# generate configuration script

echo "Create script to configure packages in qemu-user-static"

echo "
echo \"Preconfiguring dash - else dash and bash will be left in a broken state\"
/var/lib/dpkg/info/dash.preinst install

echo \"Configuring all packages\"
export DEBIAN_FRONTEND=noninteractive DEBCONF_NONINTERACTIVE_SEEN=true
export LC_ALL=C LANGUAGE=C LANG=C
dpkg --configure -a

# Establish an initial root password
echo \"Set root password to \"$rootpassword
echo root:$rootpassword | /usr/sbin/chpasswd

# By default, spawn a console on the serial port
echo \"Adding a getty on the serial port\"
echo \"T0:12345:respawn:/sbin/getty -L ttyS0 115200 vt100\" >> /etc/inittab

echo \"Tweaks to reduce flash writes as per http://www.plugcomputer.org/plugwiki/index.php/Reduce_Flash_Writes\"
echo \"
# Reduce writes to flash drives
vm.laptop_mode=5
vm.swappiness=0
vm.dirty_writeback_centisecs=1500
vm.dirty_expire_centisecs=1500
\" >> /etc/sysctl.conf

echo \"Deleting this very same script\"
rm -f /install.sh

echo \"Syncing filesystem just in case something didn't get written\"
sync

echo \"End configuration progress by exiting from the chroot\"
exit

" > $target/install.sh  

chmod 755 $target/install.sh

echo "Use qemu-user-static to perform first-boot configuration now"

mkdir -p $target/usr/bin
cp /usr/bin/qemu-arm-static $target/usr/bin
chroot $target /install.sh
rm $target/usr/bin/qemu-arm-static

echo "Syncing..."
sync

echo "Finished. You may now copy the rootfs to the plug."