#!/bin/sh -e

DVHTOOL=/usr/sbin/dvhtool
ARCBOOT_IMG=/usr/lib/arcboot/arcboot.ip22
ARCBOOT_CONF=/etc/arcboot.conf

# Use the ip32 image if we're on an O2 
if grep -E -qs '^system type[[:space:]]*: SGI (IP32|O2)' /proc/cpuinfo; then 
	ARCBOOT_IMG=/usr/lib/arcboot/arcboot.ip32
fi

if [ ! -r $ARCBOOT_CONF ]; then
	echo "No $ARCBOOT_CONF - giving up!"
	exit 1
fi

if [ ! -x $DVHTOOL ]; then
	echo "Can't find dvhtool - giving up!"
	exit 1
fi

if [ -z "$1" ]; then
	echo "Usage: arcboot <name_of_disk>"
	exit 1
fi

echo -n "Putting `basename $ARCBOOT_IMG` into the volume header of $1..."
$DVHTOOL -d $1 --unix-to-vh $ARCBOOT_IMG arcboot
echo "done."

# check if the "image=" lines in $ARCBOOT_IMG refer to valid ELF images
for i in `grep "^[[:space:]]*image="  $ARCBOOT_CONF`; do
 	IMAGE=`echo $i | cut -d'=' -f2`;
	if [ -L $IMAGE ]; then	# if it's a symlink, follow it
		IMAGE=`dirname $IMAGE`/`readlink $IMAGE`
	fi
	if [ "$(dd if=$IMAGE bs=4 count=1 2>/dev/null)" != "$(printf '\177ELF')" ]; then
		echo "Warning: $IMAGE is not an ELF image. Booting it will fail!"
	fi
done

# TODO: better sanity checking of $ARCBOOT_CONF