initramfs: Refactor alpm hooks to prevent harmless errors on kernel installation

Based on the way kdumpst alpm hooks were coded, we have currently one hook
per initrd system supported (mkinitcpio, mkinitcpio-git, dracut). When a
kernel package is installed/upgraded/removed, all of them are triggered;
but usually users only have one initrd system (enough headaches with just
one, imagine having more heh).

The net effect of this, due to the "verbiage" of alpm, is that harmless
error messages were shown, like the following one:

"error: unable to run hook 99-kdump-dracut.hook: could not satisfy
dependencies"

This one was quite common since the vast majority of Arch users rely
on mkinitcpio. And this message would show at *every* kernel package
operation, leading users to wonder what's wrong (may they pay attention
to error messages, of course).

In order to fix that, we hereby follow a great and simple suggestion from
Antiz at #archlinux-projects/Libera (thanks!): let's use a shell call to
encompass the tests for different initrd systems. With that, was easy also
to remove the redundant mkinitcpio-git hook. No functional change should
be expected from this change.

Closes: #14 ("Minimal initramfs pacman hooks should not present error messages on different init systems")
Signed-off-by: Guilherme G. Piccoli <gpiccoli@igalia.com>

Makefile

@@ -16,7 +16,7 @@ kdumpst-load.sh: kdumpst-load.header common.sh kdumpst-load.sh.in
 save-dumps.sh: save-dumps.header common.sh save-dumps.sh.in
 	cat $^ > $@
 
-99-kdump-dracut.hook: initramfs/alpm-hook.generic
+99-kdump-dracut.hook: initramfs/alpm-hook.INITRD
 	sed 's/INITRD/dracut/g' $^ > initramfs/$@
 
 kdump-dracut-hook.sh: common.sh initramfs/dracut/dracut-common.sh
@@ -31,12 +31,9 @@ module-setup.sh: initramfs/dracut/module-setup.header common.sh initramfs/dracut
 .PHONY: dracut
 dracut: 99-kdump-dracut.hook kdump-dracut-hook.sh module-setup.sh
 
-99-kdump-mkinitcpio.hook: initramfs/alpm-hook.generic
+99-kdump-mkinitcpio.hook: initramfs/alpm-hook.INITRD
 	sed 's/INITRD/mkinitcpio/g' $^ > initramfs/$@
 
-99-kdump-mkinitcpio-git.hook: initramfs/alpm-hook.generic
-	sed 's/INITRD/mkinitcpio-git/g' $^ > initramfs/$@
-
 kdump-mkinitcpio-hook.sh: common.sh initramfs/initcpio/initcpio-common.sh
 	sed 's/INITRD/mkinitcpio/g' initramfs/alpm-script.header > initramfs/alpm-header-initcpio
 	sed 's/INITRD/mkinitcpio/g' initramfs/alpm-script.sh.in > initramfs/alpm-script.sh.in-initcpio
@@ -51,7 +48,7 @@ kdump.install: initramfs/initcpio/kdump.install.header common.sh initramfs/initc
 	cat $^ > initramfs/initcpio/$@
 
 .PHONY: mkinitcpio
-mkinitcpio: 99-kdump-mkinitcpio.hook 99-kdump-mkinitcpio-git.hook kdump-mkinitcpio-hook.sh kdump.hook kdump.install
+mkinitcpio: 99-kdump-mkinitcpio.hook kdump-mkinitcpio-hook.sh kdump.hook kdump.install
 
 all: kdumpst-load.sh save-dumps.sh dracut mkinitcpio
 
@@ -64,17 +61,16 @@ install: all
 	install -D -m0644 00-default.conf $(DESTDIR)$(sharedir)/kdumpst.d/00-default
 	install -D -m0644 initramfs/99-kdump-dracut.hook $(DESTDIR)$(alpmhooksdir)/99-kdump-dracut.hook
 	install -D -m0644 initramfs/99-kdump-mkinitcpio.hook $(DESTDIR)$(alpmhooksdir)/99-kdump-mkinitcpio.hook
-	install -D -m0644 initramfs/99-kdump-mkinitcpio-git.hook $(DESTDIR)$(alpmhooksdir)/99-kdump-mkinitcpio-git.hook
+	install -D -m0644 initramfs/99-kdump-kernel.hook $(DESTDIR)$(alpmhooksdir)/99-kdump-kernel.hook
 	install -D -m0755 initramfs/dracut/kdump-dracut-hook.sh $(DESTDIR)$(libdir)/kdumpst/kdump-dracut-hook.sh
 	install -D -m0755 initramfs/kdump-collect.sh $(DESTDIR)$(libdir)/kdumpst/dracut/kdump-collect.sh
 	install -D -m0755 initramfs/dracut/module-setup.sh $(DESTDIR)$(libdir)/kdumpst/dracut/module-setup.sh
 	install -D -m0755 initramfs/initcpio/kdump-mkinitcpio-hook.sh $(DESTDIR)$(libdir)/kdumpst/kdump-mkinitcpio-hook.sh
-	install -D -m0755 initramfs/initcpio/kdump-mkinitcpio-hook.sh $(DESTDIR)$(libdir)/kdumpst/kdump-mkinitcpio-git-hook.sh
 	install -D -m0644 initramfs/initcpio/kdump.hook $(DESTDIR)$(libdir)/kdumpst/initcpio/kdump.hook
 	install -D -m0644 initramfs/initcpio/kdump.install $(DESTDIR)$(libdir)/kdumpst/initcpio/kdump.install
 
 clean:
 	rm -f kdumpst-load.sh save-dumps.sh
-	rm -f initramfs/99-kdump-*
+	rm -f initramfs/99-kdump-{mkinitcpio,dracut}.hook
 	rm -f initramfs/dracut/{kdump-dracut-hook.sh,module-setup.sh}
 	rm -f initramfs/initcpio/kdump{-mkinitcpio-hook.sh,.hook,.install}

initramfs/99-kdump-kernel.hook

@@ -4,8 +4,8 @@
 #  Maintainer: Guilherme G. Piccoli <gpiccoli@igalia.com>
 #
 #  alpm hook to deal with the kdump initramfs creation/deletion
-#  for INITRD users. This hook would act upon kernel installation,
-#  upgrade and removal, also on INITRD package installation.
+#  for initcpio or dracut. This hook would act upon kernel
+#  installation, upgrade and removal.
 #
 [Trigger]
 Type = Path
@@ -14,14 +14,8 @@ Operation = Remove
 Operation = Upgrade
 Target = usr/lib/modules/*/vmlinuz
 
-[Trigger]
-Type = Package
-Operation = Install
-Target = INITRD
-
 [Action]
-Description = Managing kdump minimal initramfs and INITRD hooks...
-Depends=INITRD
+Description = Managing kdump minimal initramfs
 When = PostTransaction
-Exec = /usr/lib/kdumpst/kdump-INITRD-hook.sh
+Exec =/bin/bash -s -c 'if command -v mkinitcpio > /dev/null; then /usr/lib/kdumpst/kdump-mkinitcpio-hook.sh; fi && if command -v dracut > /dev/null; then /usr/lib/kdumpst/kdump-dracut-hook.sh; fi'
 NeedsTargets

initramfs/alpm-hook.INITRD

@@ -0,0 +1,18 @@
+#  SPDX-License-Identifier: LGPL-2.1-or-later
+#
+#  Copyright (c) 2022 Valve.
+#  Maintainer: Guilherme G. Piccoli <gpiccoli@igalia.com>
+#
+#  alpm hook to deal with the kdump initramfs creation/deletion
+#  for INITRD. This hook would act upon INITRD package installation.
+#
+[Trigger]
+Type = Path
+Operation = Install
+Target = usr/bin/INITRD
+
+[Action]
+Description = Managing kdump minimal initramfs for INITRD installation
+When = PostTransaction
+Exec = /usr/lib/kdumpst/kdump-INITRD-hook.sh
+NeedsTargets