#!/bin/bash
set -e

# NEED ZFS HENCE USING UBUNTU KERNEL CONFIG

[[ -z $1 ]] && echo usage: ${0##*/} kernel.tar.gz && exit 1

tarball=$1
linux=${tarball%\.tar\.xz}

[[ ! -f $tarball ]] && echo $tarball nof tound && exit 1

echo
echo -n EXTRACTING $linux/...
[[ ! -d $linux/ ]] && tar xJf $tarball && echo done || echo already
cd $linux/

echo
echo -n UBUNTU CONFIG:
ls -lF /boot/config
cp -f /boot/config .config
make olddefconfig >/dev/null && echo KERNEL CONFIGURED || echo FAIL

processors=$((`grep ^processor /proc/cpuinfo | tail -1 | awk '{print $3}'` + 1))
threads=`lscpu | grep ^Thread | awk '{print $NF}'`
j=$(( processors * threads ))
unset processors threads
echo $MAKEFLAGS
echo j became $j

echo
echo -n BUILDING KERNEL...
time make -j$j > ../build0.log 2> ../build0.error.log  && echo KERNEL BUILT || echo FAIL
echo

echo
echo DEPLOYING MODULES
echo
make -j$j modules_install > ../build0.modules.log 2> ../build0.modules.error.log && echo MODULES DEPLOYED || echo FAIL

file arch/x86/boot/bzImage

cat <<EOF

Ready to go

	mv -f /vmlinuz /vmlinuz.old
	cp -i $linux/arch/x86/boot/bzImage /vmlinuz
	ls -lF /lib/modules/

EOF