From 9fd892a22413104b3a34554588468cd94d1a599e Mon Sep 17 00:00:00 2001
From: Matthias Stecher <matthiasstecher@gmx.de>
Date: Mon, 13 Jul 2020 20:31:18 +0200
Subject: [PATCH] [__lxc_container] add --restart-if-changed parameter to apply
 changes

This parameter restarts the container if configuration changes and it is
already running and should keept running. It handles the freeze state,
because it would be expected to apply changes in this state, too.
---
 .../conf/type/__lxc_container/gencode-remote  | 49 ++++++++++++++++++-
 cdist/conf/type/__lxc_container/man.rst       |  6 ++-
 .../type/__lxc_container/parameter/boolean    |  1 +
 3 files changed, 54 insertions(+), 2 deletions(-)

diff --git a/cdist/conf/type/__lxc_container/gencode-remote b/cdist/conf/type/__lxc_container/gencode-remote
index ddba593a..480d7d41 100755
--- a/cdist/conf/type/__lxc_container/gencode-remote
+++ b/cdist/conf/type/__lxc_container/gencode-remote
@@ -234,8 +234,55 @@ DONE
 rm -rf "$container_config"
 mv "\$tmpconfig" "$container_config"
 DONE
-	# write message
 	echo "config" >> "$__messages_out"
+
+
+	# restart container only if it is running
+	#  do not echo messages start/stop or melt/start/stop/freeze; only restart to avoid junk
+	case "$state_is" in
+		running|frozen)
+			# only do it if the container will run again
+			case "$state_should" in
+				present|running|frozen)
+					# su stuff
+					cat <<USER
+su "$user" - <<SU
+USER
+
+					# unfreeze if required
+					if [ "$state_is" = "frozen" ]; then
+						cat <<LXC
+lxc-unfreeze $LXC_PARAM -n "$name"
+LXC
+					fi
+
+					# stop and start
+					cat <<LXC
+lxc-stop $LXC_PARAM -n "$name"
+lxc-start $LXC_PARAM -n "$name"
+LXC
+
+					# freeze it again if it was there before, but be clever
+					# if $state_is = running but should be frozen, later code will do that
+					if [ "$state_is" = "frozen" ]; then
+						if [ "$state_should" = "frozen" ] || [ "$state_should" = "present" ]; then
+							cat <<LXC
+lxc-freeze $LXC_PARAM -n "$name"
+LXC
+						else
+							# correct current state
+							state_is="running"
+							echo "melt" >> "$__messages_out"
+						fi
+					fi
+
+					# ending
+					echo "restart" >> "$__messages_out"
+					echo "SU"
+				;;
+			esac
+			;;
+	esac
 fi
 
 
diff --git a/cdist/conf/type/__lxc_container/man.rst b/cdist/conf/type/__lxc_container/man.rst
index d0abf2e2..7d1f6522 100644
--- a/cdist/conf/type/__lxc_container/man.rst
+++ b/cdist/conf/type/__lxc_container/man.rst
@@ -70,7 +70,11 @@ config-absent
 
 BOOLEAN PARAMETERS
 ------------------
-None.
+
+restart-if-changed
+    Restarts the container if configuration changes. It stop and start the container that new configuration
+    can be applied. If it whould be restarted with ``lxc-stop -n $name --reboot``, configuration changes
+    would be ignored.
 
 CREATE PARAMETERS
 -----------------
diff --git a/cdist/conf/type/__lxc_container/parameter/boolean b/cdist/conf/type/__lxc_container/parameter/boolean
index caf89a8e..724fa14b 100644
--- a/cdist/conf/type/__lxc_container/parameter/boolean
+++ b/cdist/conf/type/__lxc_container/parameter/boolean
@@ -1 +1,2 @@
 no-default-config
+restart-if-changed