xbps-triggers: add initramfs-regenerate trigger

This abstracts away the `dracut -f -q --regenerate-all` that appears in
nvidia and zfs packages, allowing users to disable global regeneration,
use dracut (by default, to preserve existing behavior) or mkinitcpio.
Eventually, this can be extended with initramfs-tools if we like.

Closes: #31403

Manual.md

@@ -57,6 +57,7 @@ packages for XBPS, the `Void Linux` native packaging system.
 		* [gtk3-immodules](#triggers_gtk3_immodules)
 		* [hwdb.d-dir](#triggers_hwdb.d_dir)
 		* [info-files](#triggers_info_files)
+		* [initramfs-regenerate](#triggers_initramfs_regenerate)
 		* [kernel-hooks](#triggers_kernel_hooks)
 		* [mimedb](#triggers_mimedb)
 		* [mkdirs](#triggers_mkdirs)
@@ -1881,6 +1882,35 @@ registry located at `usr/share/info`.
 If it is running under another architecture it tries to use the host's `install-info`
 utility.
 
+<a id="triggers_initramfs_regenerate"></a>
+### initramfs-regenerate
+
+The initramfs-regenerate trigger will trigger the regeneration of all kernel
+initramfs images after package installation or removal. The trigger must be
+manually requested.
+
+This hook is probably most useful for DKMS packages because it will provide a
+means to include newly compiled kernel modules in initramfs images for all
+currently available kernels. When used in a DKMS package, it is recommended to
+manually include the `dkms` trigger *before* the `initramfs-regenerate` trigger
+using, for example,
+
+    ```
+    triggers="dkms initramfs-regenerate"
+    ```
+
+Although `xbps-src` will automatically include the `dkms` trigger whenever
+`dkms_modules` is installed, the automatic addition will come *after*
+`initramfs-regenerate`, which will cause initramfs images to be recreated
+before the modules are compiled.
+
+By default, the trigger uses `dracut --regenerate-all` to recreate initramfs
+images. If `/etc/defalt/initramfs-regenerate` exists and defines
+`INITRAMFS_GENERATOR=mkinitcpio`, the trigger will instead use `mkinitcpio` and
+loop over all kernel versions for which modules appear to be installed.
+Alternatively, setting `INITRAMFS_GENERATOR=none` will disable image
+regeneration entirely.
+
 <a id="triggers_kernel_hooks"></a>
 #### kernel-hooks
 

srcpkgs/xbps-triggers/files/initramfs-regenerate

@@ -0,0 +1,72 @@
+#!/bin/sh
+#
+# Trigger to regenerate an initramfs for every kernel with a module directory
+# in lib/modules on package post-install.
+#
+# To change the initramfs generator, edit or create the file
+# etc/default/initramfs-regenerate and add or change the line
+#
+#     INITRAMFS_GENERATOR=<generator>
+#
+# where <generator> is one of "dracut", "mkinitcpio" or "none". By default, a
+# value of "dracut" is assumed.
+#
+# Arguments:	$ACTION = [run/targets]
+#		$TARGET = [post-install/post-remove]
+#		$PKGNAME
+#		$VERSION
+#		$UPDATE = [yes/no]
+
+ACTION="$1"
+TARGET="$2"
+PKGNAME="$3"
+VERSION="$4"
+UPDATE="$5"
+
+export PATH="usr/bin:/usr/sbin:/usr/bin:/sbin:/bin"
+
+case "$ACTION" in
+	targets)
+		echo "post-install post-remove"
+		exit 0
+		;;
+	run)
+		;;
+	*)
+		exit 1
+		;;
+esac
+
+# Read the configuration, if it exists
+[ -f etc/default/initramfs-regenerate ] && . etc/default/initramfs-regenerate
+
+# dracut explicitly sets umask 0077, other generators may not
+umask 0077
+
+case "${INITRAMFS_GENERATOR:-dracut}" in
+	dracut)
+		if command -v dracut >/dev/null 2>&1; then
+			echo "Regenerating initramfs with dracut"
+			dracut -f -q --regenerate-all
+		fi
+		;;
+	mkinitcpio)
+		if command -v mkinitcpio >dev/null 2>&1; then
+			echo "Regenerating initramfs with mkinitcpio"
+			# Regenerate images for every kernel version with modules
+			for kdir in usr/lib/modules/*; do
+				[ -d "${kdir}/kernel" ] || continue
+				kver="${kdir##*/}"
+				mkinitcpio -g "boot/initramfs-${kver}.img" -k "${kver}"
+			done
+		fi
+		;;
+	none)
+		;;
+	*)
+		echo "unrecognized INITRAMFS_GENERATOR for initramfs-regenerate hook"
+		exit 1
+		;;
+esac
+
+exit 0

srcpkgs/xbps-triggers/template

@@ -1,6 +1,6 @@
 # Template file for 'xbps-triggers'
 pkgname=xbps-triggers
-version=0.120
+version=0.121
 revision=1
 bootstrap=yes
 short_desc="XBPS triggers for Void Linux"