add setup script

boot/cmdline.txt

@@ -1 +1 @@
-dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait
+dwc_otg.lpm_enable=0 console=serial0,115200 console=tty1 root=/dev/mmcblk0p2 rootfstype=ext4 elevator=deadline fsck.repair=yes rootwait init=/root/init_setup.sh

build.sh

@@ -110,6 +110,27 @@ EOL
 useradd -s /bin/bash --create-home -p $(perl -e 'print crypt("raspberry", "password")') pi
 echo "pi ALL=(ALL) NOPASSWD: ALL" > /etc/sudoers.d/010_pi-nopasswd
 
+cat > /root/init_setup.sh <<EOL
+#!/bin/sh
+
+mount -t proc proc /proc
+mount -t sysfs sys /sys
+mount /boot
+mount -o remount,rw /
+
+parted /dev/mmcblk0 u s resizepart 2 \\\$(expr \\\$(cat /sys/block/mmcblk0/size) - 1)
+resize2fs /dev/mmcblk0p2
+
+sed -i 's| init=/root/init_setup.sh||' /boot/cmdline.txt
+sync
+
+echo 1 > /proc/sys/kernel/sysrq
+rm /root/init_setup.sh
+echo b > /proc/sysrq-trigger
+EOL
+
+chmod +x /root/init_setup.sh
+
 apt-get clean
 rm -rf /var/lib/apt/lists/*
 EOF

multistrap.conf

@@ -5,7 +5,7 @@ debootstrap=Debian
 aptsources=Debian
 
 [Debian]
-packages=apt kmod dialog netbase net-tools ethtool iproute iputils-ping ifupdown isc-dhcp-client sudo ssh avahi-daemon vim
+packages=apt kmod dialog netbase net-tools ethtool iproute iputils-ping ifupdown isc-dhcp-client sudo ssh avahi-daemon vim parted
 source=http://deb.debian.org/debian/
 keyring=debian-archive-keyring
 suite=jessie