#!/bin/sh
# The initramfs images as the mesh builds them (module kernel, novox/hq issue 1977). Run by
# mesh-kernel-initramfs.service:
#
#   initramfs apply [<the microcode drop-in> [<this module's state> [<mkinitcpio file>]]]
#
# `apply` builds every image again (mkinitcpio -P) when the drop-in differs from the one the images were last built
# with, kept in the state as `initramfs-built`, and records the drop-in only after mkinitcpio succeeded. Later
# kernel upgrades build the images through the distribution's own hook, with the drop-in in place. The arguments
# are only for the module's tests.
set -eu

dropin=/etc/mkinitcpio.conf.d/mesh-microcode.conf
state='${dir:state}'
[ $# -ge 2 ] && dropin=$2
[ $# -ge 3 ] && state=$3

[ $# -ge 1 ] && [ "$1" = apply ] || {
	echo "usage: initramfs apply [<drop-in> [<state directory>]]" >&2
	exit 2
}
[ -f "$dropin" ] || {
	echo "initramfs: $dropin is not there, so the images cannot be built with the microcode hook" >&2
	exit 1
}
if [ -f "$state/initramfs-built" ] && cmp -s "$dropin" "$state/initramfs-built"; then
	echo "initramfs: the images were built with this drop-in, as it was"
	exit 0
fi
if ! mkinitcpio -P; then
	echo "initramfs: mkinitcpio failed; nothing recorded, the next start tries again" >&2
	exit 1
fi
cp "$dropin" "$state/initramfs-built.new"
mv "$state/initramfs-built.new" "$state/initramfs-built"
echo "initramfs: the images are built with the microcode drop-in"