apt-get update && apt-get -y install squashfs-tools

cp /srv/tftp/clonezilla/live/filesystem.squashfs /tmp
cd /tmp
unsquashfs filesystem.squashfs

cat <<'EOF' >> squashfs-root/usr/local/bin/pre_run
#!/bin/bash

echo "Inserire la partizione root (/dev/sdx1)"
read ROOT_PARTITION
echo $ROOT_PARTITION > /tmp/ROOT_PARTITION
echo "Inserire il nuovo nome host: "
read NEWHOST
echo $NEWHOST > /tmp/NEWHOST
EOF

chmod 755 squashfs-root/usr/local/bin/pre_run

cat <<'EOF' >> squashfs-root/usr/local/bin/post_run
#!/bin/bash

ROOT_PARTITION=$(</tmp/ROOT_PARTITION)
sudo mount $ROOT_PARTITION /mnt
HOSTN=$(</mnt/etc/hostname)
echo "Existing hostname is $HOSTN"
NEWHOST=$(</tmp/NEWHOST)
sudo sed -i "s/$HOSTN/$NEWHOST/g" /mnt/etc/hosts
sudo sed -i "s/$HOSTN/$NEWHOST/g" /mnt/etc/hostname
sudo echo "Nuovo nome host: $NEWHOST"
read -s -n 1 -p "Riavvia"
sudo reboot
EOF

chmod 755 squashfs-root/usr/local/bin/post_run

mksquashfs squashfs-root filesystem.squashfs.new -b 1024k -comp xz -Xbcj x86 -e boot
cp filesystem.squashfs.new /srv/tftp/clonezilla/live/filesystem.squashfs
rm -rf filesystem.squashfs filesystem.squashfs squashfs-root/ -rf 

sed -i '/APPEND/s/$/ ocs_prerun=\"\/usr\/local\/bin\/pre_run\" ocs_postrun=\"\/usr\/local\/bin\/post_run\"/' /srv/tftp/pxelinux.cfg/default
systemctl restart tftpd-hpa