#!/bin/bash -x

export PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"
mount -t devtmpfs udev /dev
mount -t proc proc /proc
mount -t sysfs sysfs /sys

APP="$(sed s/^.*app=// /proc/cmdline)"

mount --bind "$APP/uml/modules" /lib/modules

ifconfig eth0 up
ifconfig eth0 10.0.2.15
route add default dev eth0

modprobe fuse
modprobe ext4
modprobe loop
mount "$APP/shadow_root.img" "$APP/shadow_root" -t ext4
LD_LIBRARY_PATH="$APP/uml" "$APP/uml/unionfs" -o rw,cow "$APP/shadow_root=RW:/=RO" "$APP/shadow_mount"

mount --bind /proc "$APP/shadow_mount/proc"
mount --bind /dev "$APP/shadow_mount/dev"
mount --bind /sys "$APP/shadow_mount/sys"

mkdir "$APP/shadow_mount/app"
mount --bind "$APP/root" "$APP/shadow_mount/app"

chroot "$APP/shadow_mount" bash -c "$(cat "$APP/uml_command")"

umount "$APP/shadow_mount/dev" "$APP/shadow_mount/proc" "$APP/shadow_mount/sys"
umount "$APP/shadow_mount"
umount "$APP/shadow_root"
mount -o remount,ro,sync /dev/root /
halt -f