Fix #76: Rebuild initramfs, when installing a initramfs hook

Also shellcheck all *.trigger files from now on in the static code analysis.

postmarketos-mkinitfs/APKBUILD

@@ -1,11 +1,11 @@
 pkgname=postmarketos-mkinitfs
 pkgver=0.0.5
-pkgrel=3
+pkgrel=4
 pkgdesc="Tool to generate initramfs images for postmarketOS"
 url="https://github.com/postmarketOS"
 # multipath-tools: kpartx
 depends="busybox-extras lddtree cryptsetup kmod multipath-tools"
-triggers="$pkgname.trigger=/usr/share/kernel/*"
+triggers="$pkgname.trigger=/etc/postmarketos-mkinitfs/hooks:/usr/share/kernel/*"
 source="init.sh.in init_functions.sh mkinitfs.sh 10-usb-unlock.sh splash1.ppm.gz splash2.ppm.gz"
 arch="noarch"
 license="GPL2"

postmarketos-mkinitfs/postmarketos-mkinitfs.trigger

@@ -1,24 +1,52 @@
 #!/bin/sh
 
+# $1: kernel flavor
+rebuild_initfs_flavor()
+{
+	abi_release=$(cat /usr/share/kernel/"$1"/kernel.release)
+	mkinitfs -o /boot/initramfs-"$1" "$abi_release"
+}
+
+# Each argument to this shell script is a path, that caused the trigger to
+# execute. When a hook was changed, rebuild all flavors. When only one flavor
+# was changed, find out if it has been installed or uninstalled, and rebuild
+# it or delete the left-overs.
+rebuild_all="false"
 for i in "$@"; do
-	# get last element in path
-	flavor=${i##*/}
-	if ! [ -f "$i"/kernel.release ]; then
-		# kernel was uninstalled
-		rm -f $( readlink -f /boot/initramfs-$flavor ) \
-			/boot/initramfs-$flavor /boot/vmlinuz-$flavor \
-			/boot/$flavor /boot/$flavor.gz /$flavor /$flavor.gz
-		continue
-	fi
-	abi_release=$(cat "$i"/kernel.release)
-	initfs=initramfs-$flavor
-	mkinitfs -o /boot/$initfs $abi_release
+	case "$i" in
+		# Hook change
+		/etc/postmarketos-mkinitfs/hooks*)
+			rebuild_all="true"
+			break ;;
+
+		# Kernel flavor change
+		/usr/share/kernel/*)
+			flavor=${i##*/}
+			if [ -f "$i"/kernel.release ]; then
+				# installed
+				[ "$rebuild_all" = "true" ] || rebuild_initfs_flavor "$flavor"
+			else
+				# uninstalled
+				rm -f "$( readlink -f /boot/initramfs-"$flavor" )" \
+					/boot/initramfs-"$flavor" /boot/vmlinuz-"$flavor" \
+					/boot/"$flavor" /boot/"$flavor".gz /"$flavor" /"$flavor".gz
+			fi
+
+			break ;;
+	esac
 done
 
-# cleanup unused initramfs
+# Rebuild all flavors, if necessary
+if [ "$rebuild_all" = "true" ]; then
+	for i in /usr/share/kernel/*; do
+		[ -d "$i" ] && rebuild_initfs_flavor "${i##*/}"
+	done
+fi
+
+# Cleanup unused initramfs
 for i in /boot/initramfs-[0-9]*; do
-	[ -f $i ] || continue
-	if ! [ -f /boot/vmlinuz-${i#/boot/initramfs-} ]; then
+	[ -f "$i" ] || continue
+	if ! [ -f /boot/vmlinuz-"${i#/boot/initramfs-}" ]; then
 		rm "$i"
 	fi
 done