#!/bin/bash
#

DRIVER="hp-be2net-2.102.435.0.tar.gz"
INITRDOUT="initrd.gz-$(date +%Y%m%d)"
#KVER="2.6.32-5-amd64"

set -e

# Make sure we can create devices and preserve permissions.
if [ "$(whoami)" != "root" ]; then
	which fakeroot >/dev/null 2>&1
	if [ $? -ne 0 ]; then
		echo "You must install the fakeroot package to build as a user."
		exit 1
	fi
	echo "Re-executing under fakeroot..."
	exec fakeroot $0
	echo "exec fakeroot failed with return code: $?"
	exit 1
fi

# Check for a linux-headers package to use.
if [ $KVER ]; then
	KPATH="/usr/src/linux-headers-$KVER"
else
	KPATH=$(dpkg -l 'linux-headers-*' | egrep '^ii' | egrep -v 'common|meta' | awk 'END { print $2 }')
	if [ $KPATH ]; then
		KVER=$(echo $KPATH | sed 's/linux-headers-//')
		KPATH="/usr/src/$KPATH"
	else
		echo "Unable to discover an installed linux-headers package."
		echo "You must install one to proceed (hint: apt-get install linux-headers)"
		exit 1
	fi
fi

# Make sure the user provided an initrd to work on.
if [ ! -f ./initrd.gz ]; then
	echo "You must put the target initrd.gz file in the same directory as this script."
	exit 1
fi

echo -e "DRIVER=$DRIVER\nINITRDOUT=$INITRDOUT\nKVER=$KVER\nKPATH=$KPATH"

# Might need to make these.
mkdir -p initrd module

# Rebuild the HP driver for the current kernel...
echo -e "\nBUILD MODULE"
tar xzf hp-be2net-*.tar.gz -C module --strip-components=1
(
	cd module
	make -C "$KPATH" modules M="$PWD" CONFIG_BE2NET=m
)

# Rebuild the initd image with this be2net driver.
echo -e "\nREBUILD INITRD"
(
	cd initrd
	gzip -dc ../initrd.gz | cpio -id
	mkdir -p "lib/modules/$KVER/kernel/drivers/net/benet"
	cp ../module/be2net.ko "lib/modules/$KVER/kernel/drivers/net/benet/"
	fgrep 'be2net.ko:' "lib/modules/$KVER/modules.dep" >/dev/null 2>&1 && {
		sed -r -i -e 's#^(kernel/drivers/net/benet/be2net.ko:)\s*$#\1 kernel/net/ipv4/inet_lro.ko#' "lib/modules/$KVER/modules.dep"
	} || {
		fgrep 'be2net.ko:' "lib/modules/$KVER/modules.dep" ||
			echo "kernel/drivers/net/benet/be2net.ko: kernel/net/ipv4/inet_lro.ko" >> "lib/modules/$KVER/modules.dep"
	}
	ls -l "lib/modules/$KVER/kernel/drivers/net/benet/"
	fgrep 'be2net.ko:' "lib/modules/$KVER/modules.dep"
	find ./ | cpio -H newc -o > "../$INITRDOUT"
)

echo -e "\nNew initrd.gz is:  $(pwd)/$INITRDOUT"

# Clean up after ourselves.
rm -rf module/.[a-z]* module/* initrd/*