debian qemu scripts

$ cat /etc/network/interfaces
auto lo
iface lo inet loopback

auto eth0
iface eth0 inet dhcp

#auto br0
iface br0 inet dhcp
	pre-up tunctl -t tap0 -g tuntap
	pre-up tunctl -t tap1 -g tuntap
	pre-up ip link set tap0 up
	pre-up ip link set tap1 up
	bridge_ports eth0 tap0 tap1
	bridge_stp off
	bridge_maxwait 0
	bridge_fd 0
	post-down ip link set tap0 down
	post-down ip link set tap1 down
	post-down tunctl -d tap0
	post-down tunctl -d tap1


$ cat bin/debqemu.sh
#!/bin/sh

quit()
{
	ret=0
	if [ $# -gt 0 ];
	then
		ret=$1
		shift
	fi
	if [ $# -gt 0 ];
	then
		printf "$1\n"
		shift
	fi
	exit $ret
}

image=""
kernel=""
if [ "x$1" = "xle" ];
then
	qemu=qemu-system-mipsel
	image="$HOME/code/debian-qemu/le/debian_squeeze_mipsel_standard.qcow2"
	kernel="$HOME/code/debian-qemu/le/vmlinux-2.6.32-5-4kc-malta"
	iface=tap1
	# reset /etc/udev/rules.d/70-persistent-net.rules in qemu guest if you change mac addrs
	macaddr="52:54:00:12:34:57"
elif [ "x$1" = "xbe" ];
then
	qemu=qemu-system-mips
	image="$HOME/code/debian-qemu/be/debian_squeeze_mips_standard.qcow2"
	kernel="$HOME/code/debian-qemu/be/vmlinux-2.6.32-5-4kc-malta"
	iface=tap0
	# reset /etc/udev/rules.d/70-persistent-net.rules in qemu guest if you change mac addrs
	macaddr="52:54:00:12:34:56"
else
	quit 1 "Specify le or be endianness."
fi

if [ ! -d ~/code/debian-qemu ];
then
	sudo mount /srv/endor/code || quit 1 "Failed to mount /srv/endor/code";
fi

echo "Stopping eth0, starting br0."

bridge.sh || quit 1 "Failed to start br0."

echo "Starting Debian system QEMU session."


$qemu -net nic,macaddr=$macaddr  -net tap,ifname=$iface,script=no,downscript=no -nographic -M malta -kernel $kernel -hda $image -append "root=/dev/sda1 console=tty0"

$ cat /home/zach/bin/bridge.sh
#!/bin/sh

sudo ifdown eth0
sudo ifup br0