50-dracut.install: add exit condition for pre-existing image

essentially mirrors what the upstream systemd equivalent also does

Signed-off-by: Nowa Ammerlaan <[email protected]>

hooks/50-dracut.install

@@ -8,9 +8,9 @@
 
 ver=${1}
 img=${2}
-initrd="${INSTALLKERNEL_STAGING_AREA}/initrd"
-uki="${INSTALLKERNEL_STAGING_AREA}/uki.efi"
-tmp="${INSTALLKERNEL_STAGING_AREA}/dracut-tmp"
+initrd="${INSTALLKERNEL_STAGING_AREA:-$(dirname "${img}")}/initrd"
+uki="${INSTALLKERNEL_STAGING_AREA:-$(dirname "${img}")}/uki.efi"
+tmp="${INSTALLKERNEL_STAGING_AREA:-$(dirname "${img}")}/dracut-tmp"
 
 # familiar helpers, we intentionally don't use Gentoo functions.sh
 die() {
@@ -53,10 +53,24 @@ main() {
 		einfo "Using dracut as the initramfs and UKI generator..."
 		initramfs_gen_args+=( --uefi )
 		out="${uki}"
+		if [[ -f $(dirname "${img}")/uki.efi ]]; then
+			einfo "There is an UKI image at the same place as the kernel, skipping generating a new one"
+			cp --reflink=auto "$(dirname "${img}")/uki.efi" "${uki}" || die
+			chown root:root "${uki}" || die
+			chmod 0600 "${uki}" || die
+			exit 0
+		fi
 	elif [[ ${INSTALLKERNEL_INITRD_GENERATOR} == dracut ]]; then
 		einfo "Using dracut as the initramfs generator..."
 		initramfs_gen_args+=( --no-uefi )
 		out="${initrd}"
+		if [[ -f $(dirname "${img}")/initrd ]]; then
+			einfo "There is an initramfs image at the same place as the kernel, skipping generating a new one"
+			cp --reflink=auto "$(dirname "${img}")/initrd" "${initrd}" || die
+			chown root:root "${initrd}" || die
+			chmod 0600 "${initrd}" || die
+			exit 0
+		fi
 	else
 		einfo "No install.conf preference set, falling back to dracut.conf..."
 		out="${tmp}"