#!/bin/sh -x

myname=`basename $0`
dirname=`dirname $0`
macaddr=00:0B:DC:9B:D6:DA
base=dc=priv,dc=lcl
exe=qemu-kvm
qemu_opts=""
brctl=`PATH=/usr/sbin:/sbin /usr/bin/which brctl`
#nic_model=",model=rtl8139"

usage()
{
cat << EOT >&2

 $myname -h
 $myname {net|<image-file>} [-b hostname]

EOT
	[ "$1" ] && exit $1
	exit 0
}

err()
{
	echo $* >&2
}

fatal()
{
	err $@
	exit 1
}

do_sudo()
{
	if [ "$UID" = 0 ]; then
		while [[ $1 =~ ^- ]]; do shift; done
		eval "$@"
		return $?
	else
		echo running sudo $@
		#sudo -p "Password for $myname:" $@
		eval sudo "$@"
		return $?
	fi
}

ldap_search()
{
	local ldap_server=ldap.lcl
	local binddn=cn=ldapadm,dc=jannet,dc=de
	local password_file=$HOME/.feedfs-ldap/passwords/$binddn@$ldap_server
	[ -r "$password_file" ] || fatal "Password file $password_file doesn't exist"
	ldapsearch -y $password_file -xZ -h $ldap_server -D $binddn -b $base,ou=networks,dc=jannet,dc=de $@
}

list_hostnames()
{
	ldap_search -LLL "(objectClass=dhcpHost)" cn | sed '/cn: / !d; s/cn: //'
}

boot_net()
{
	[ "$hostname" ] && {
		set -x
		macaddr=`ldap_search -LLL "(cn=$short_hostname) dhcpHWAddress" | 
			sed '/dhcpHWAddress:/ !d; s/dhcpHWAddress: ethernet *//'`
	}

	xhost +
	do_sudo /sbin/modprobe kvm-intel

	ps aux | grep -v grep | grep -q dhcpd || /etc/init.d/dhcpd start
	ps aux | grep -v grep | grep -q nfsd || /etc/init.d/nfsserver start

	[ "$nic_model" ] || nic_model=",model=e1000"
	# need this for net access, would be nicer if it didn't run as root
	# -nographic
	do_sudo -E /usr/bin/$exe  \
		-boot n  \
		-net tap,ifname=tap0,vlan=0,script=$tmpdir/qemu-ifup,downscript=$tmpdir/qemu-ifdown \
		-net nic,vlan=0$nic_model,macaddr=$macaddr \
		"$qemu_opts"
}

boot_image()
{
	local boot_image="$1"

	test -r "$boot_image" || fatal "inaccessible boot image \"$boot_image\""

	xhost +
	do_sudo -E /usr/bin/$exe  \
		-net tap,ifname=tap0,vlan=0,script=$tmpdir/qemu-ifup,downscript=$tmpdir/qemu-ifdown \
		-net nic,vlan=0$nic_model,macaddr=$macaddr \
		"$qemu_opts" \
		-drive format=raw,file=$boot_image
}

boot()
{
	local tmpdir=`mktemp -d /tmp/$myname""_XXXXXX`
	(
		cd $tmpdir
		ln -s $0 qemu-ifup
		ln -s $0 qemu-ifdown
	)

	case $1 in
	net)
		boot_net
		;;
	*)
		boot_image "$@"
		;;
	esac

	rm -rf $tmpdir
}

# -- here we go

OPTIND=1
while getopts lhb:o:x:n: flag; do
	case $flag in
	h)
		usage 0;;
	l)
		list_hostnames
		exit 0;;
	b)
		hostname="$OPTARG"
		short_hostname=`echo $hostname | sed 's/\..*//'`
		dns_domain=`echo $hostname | cut -d. -f2-`
		base=`echo $dns_domain | sed 's/\./,/g; s/\(^\|,\)/\1dc=/g'`
		;;
	x)
		exe="$OPTARG";;
	o)
		qemu_opts="$OPTARG";;
	n)
		nic_model=",model=$OPTARG";;
	*)
		usage 1;;
	esac
done
shift $(($OPTIND - 1))

case $myname in
*ifup*)
	do_sudo /sbin/ifconfig $1 up
	do_sudo $brctl addif priv0 $1
	;;

*ifdown*)
	do_sudo $brctl delif priv0 $1
	do_sudo /sbin/ifconfig $1 down
	;;
qemu.sh)
	boot "$@"
	;;
qemu-boot.sh) # legacy
	boot "$@"
	;;
*)
	echo called as unknown executable name $0
	;;
esac