#! /bin/bash
#
# Normally installed in /etc/initramfs/post-update.d/ and marked
# executable.
#
# Move newly installed initramfs to /boot/efi and ensure corresponding
# kernel is also moved.  If the kernel has to be moved, also update
# the EFI Boot Manager with the new kernel and prune old kernels.
#
# This routine is called the kernel version in argument #1 and the 
# name of the initramfs file in argument #2

# Obtain root fs info for boot command line
source <(blkid -o export $(df / |grep -o '^/dev/[^ ]\+')) 
if test "${DEVNAME:0:12}" == "/dev/mapper/" ; then
	export RootSpec="$DEVNAME"
else
	if test "${DEVNAME:0:5}" == "/dev/" ; then
		vglv="${DEVNAME:5}"
		vg="${vglv%%/*}"
		lv="${vglv#$vg}"
		if test -n "$lv" ; then
			export RootSpec="$DEVNAME"
		else
			export RootSpec="UUID=$UUID"
		fi
	else
		export RootSpec="UUID=$UUID"
	fi
fi

# Destinations must have a trailing slash.
for DEST in /bootB/ /bootA/
do
	# First, copy the updated initramfs.
	cp "$2" "$DEST"

	# Construct the target kernel efi file name and check for existence
	export KF="${DEST}vmlinuz-$1.efi"
	test -f "$KF" && continue

	# Need to copy and register the kernel.
	echo "Copying $KF ..."
	cp "/boot/vmlinuz-$1" "$KF"

	# Obtain EFI boot fs info for boot partition info and file locations
	source <(blkid -o export $(df "$DEST" |grep -o '^/dev/[^ ]\+')) 

	BOOT="$(sed -r -e 's/(.+[^0-9])([0-9]+)/\1:\2/' <<< "$DEVNAME")"
	read dummy1 MOUNTPT other <<< "$(grep "^$DEVNAME " /proc/mounts)"
	EFIROOT="$(echo ${DEST##$MOUNTPT} |sed 's/\//\\/g')"

	# Set the new boot record
	efibootmgr -q -c --disk "${BOOT%%:*}" --part "${BOOT##*:}" \
		--label "EFI Direct $DEST $1" \
		--loader "${EFIROOT}vmlinuz-$1.efi" \
		-u "initrd=${EFIROOT}$(basename "$2") root=${RootSpec}"

	echo "Configured EFI Direct $DEST $1 as $EFIROOT on $BOOT"

done