grub-btrfs: New package

This kind of grub addon will extend the grub boot menu by a additional
submenu where a BTRFS snapshot can be selected to directly use as root
volume and boot into it.

The grub-btrfsd daemon is using inotify(tools) to watch the snapshot directory for
new or deleted snapshots and calls grub-mkconfig to adjust the snapshot grub submenu

Signed-off-by: Stefan Schantl <stefan.schantl@ipfire.org>
Signed-off-by: Arne Fitzenreiter <arne_f@ipfire.org>

src/initscripts/system/grub-btrfsd

@@ -0,0 +1,61 @@
+#!/bin/sh
+###############################################################################
+#                                                                             #
+# IPFire.org - A linux based firewall                                         #
+# Copyright (C) 2007-2024  IPFire Team  <info@ipfire.org>                     #
+#                                                                             #
+# This program is free software: you can redistribute it and/or modify        #
+# it under the terms of the GNU General Public License as published by        #
+# the Free Software Foundation, either version 3 of the License, or           #
+# (at your option) any later version.                                         #
+#                                                                             #
+# This program is distributed in the hope that it will be useful,             #
+# but WITHOUT ANY WARRANTY; without even the implied warranty of              #
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the               #
+# GNU General Public License for more details.                                #
+#                                                                             #
+# You should have received a copy of the GNU General Public License           #
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.       #
+#                                                                             #
+###############################################################################
+
+. /etc/sysconfig/rc
+. ${rc_functions}
+
+SNAPSHOTDIR="/.snapshots"
+PIDFILE="/run/grub-btrfsd.pid"
+
+root_is_btrfs() {
+    [ "$(stat -f --format="%T" /)" == "btrfs" ] || return 1
+
+    return 0
+}
+
+case "$1" in
+        start)
+		root_is_btrfs || exit 0
+
+		boot_mesg "Starting Grub/Btrfs snapshot manager..."
+		loadproc -b -p "$PIDFILE" /usr/bin/grub-btrfsd --syslog "$SNAPSHOTDIR"
+
+		# Store the gained PID to the defined pidfile
+		echo "$!" > "$PIDFILE"
+	;;
+
+	stop)
+		boot_mesg "Stopping grub-btrfsd..."
+		killproc -p "$PIDFILE" /usr/bin/grub-btrfsd
+		sleep 1;
+	;;
+
+	restart)
+		$0 stop
+		sleep 2
+		$0 start
+	;;
+
+	*)
+		echo "Usage: $0 {start|stop|restart}"
+		exit 1
+	;;
+esac