#!/bin/sh
#
#	mkboot 2.0 - make boot floppy, make root device bootable, etc.
#							Author: Kees J. Bot

usage() {
	echo "Usage: $0 [bootable | hdboot [minix or image] | fdboot [device]]" >&2
	exit 1
}

rotate_oldest() {
	base_dir="$1"
	set -- `ls -t "$base_dir"`

	case $# in
	0|1|2|3)
		# Not much there, do not remove a thing.
		;;
	*)
		# Remove the third-newest $hdboot_t in /boot/$hdboot_t, but
		# only if there's an older one (which is kept). 
		echo "rm $root:$base_dir/$3"
		rm -rf "$base_dir/$3"
	esac
}


trap 'e=$?; rm -f /tmp/mkb.$$; exit $e' 0 2

mdec=/usr/mdec	# bootstraps

# Check arguments.
case "$#:$1" in
1:bootable | 2:hdboot | [12]:fdboot )
	action=$1 dev=$2 size=$3
	;;
*)	usage
esac

if [ "$1" = "hdboot" ]
then
	if [ "$2" != "image" -a "$2" != "minix" ]
	then usage
	fi
	hdboot_t="$2"
fi

# Get the device table.
FSTAB=/etc/fstab
touch $FSTAB
if grep -q "Poor man" $FSTAB
then	. $FSTAB
else	root="`awk <$FSTAB '{ if($2=="/") { print $1 } }'`"
fi

# The real root device may be the RAM disk.
realroot=`printroot -r`

# If it's an initial fstab, pretend root is real root
if [ "$root" = "/dev/ROOT" -o -z "$root" ]
then	root=$realroot
fi

case $action in
bootable | hdboot)
	# We need the root device.

	if [ $realroot = $root ]
	then
		rootdir=
	else
		umount $root 2>/dev/null
		mount $root /mnt || exit
		rootdir=/mnt
	fi
esac

case $action in
hdboot)
	# Install a new image on the root device.
	if [ -e $rootdir/boot/$hdboot_t -a ! -d $rootdir/boot/$hdboot_t ]
	then
		# /boot/$hdboot_t is not yet a directory!  Fix it.
		su root -c \
		    "exec mv $rootdir/boot/$hdboot_t /M"
		install -d $rootdir/boot/$hdboot_t
		su root -c \
		    "exec mv $rootdir/M $rootdir/boot/$hdboot_t/`uname -r`"
	fi

	sh tell_config OS_RELEASE . OS_VERSION >/tmp/mkb.$$
	version=`sed 's/[" 	]//g;/^$/d' </tmp/mkb.$$`

	# Retrieve the git revision; this only succeeds
	# if git is available, it's a git checkout, *and*
	# there are no uncommitted changes.
	if git diff --quiet 2>/dev/null
	then	gitrev="-`git describe --always`"
	fi

	revision=`cat revision 2>/dev/null`

	if [ -z "$revision" ]
	then	rrevision=""
		gitrev=""
	else	rrevision=r$revision
	fi

	oldrev=$revision

	if [ -z "$revision" ]
	then
		revision=0
		rrevision=""
	else
		revision=`expr $revision + 1`
		rrevision=r$revision
	fi

	target="${version}${rrevision}${gitrev}"

	rotate_oldest "$rootdir/boot/$hdboot_t"

	# rotate system processes. We assume latest ones are in
	# /boot/modules/.temp and we maintain /boot/modules/ by ourselves.
	if [ "$hdboot_t" = "minix" ]
	then
		[ -d /boot/minix/.temp ] || exit 1
		rm -rf /boot/minix/"$target"/
		mv /boot/minix/.temp /boot/minix/"$target"
		rm -f /boot/minix_latest
		ln -s minix/"$target" /boot/minix_latest 
	else
		# Install the new image.
		echo "install $hdboot_t $root:/boot/$hdboot_t/$target"
		install -o root -m 600 $hdboot_t $rootdir/boot/$hdboot_t/$target || exit 1

		# Tell bootloader which image is newest
		ln -f $rootdir/boot/$hdboot_t/$target $rootdir/boot/${hdboot_t}_latest
	fi

	# Save the revision number.
	test "$revision" != "$oldrev" && echo $revision >revision

	test $realroot != $root && umount $root
	echo "Done."
	;;
esac
sync
exit 0