confd: add support for upgrading container images

This patch adds a new CLI command 'container upgrade foo', where 'foo'
is the name of the container.  If more than one container use the same
image, multiple upgrades must be done because a container runs not on
the 'image:tag' but on the hash of the 'image:tag' it was created from.

Rename "done" queue to "active", since we want to recreate an active
container after fetching an updated base image.

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>

board/common/rootfs/usr/sbin/container

@@ -246,6 +246,17 @@ case $cmd in
     stop)
 	initctl -bq stop "container:$1" || podman kill "$1"
 	;;
+    upgrade)
+	img=$(podman inspect "$1" | jq -r .[].ImageName)
+	if [ -z "$img" ]; then
+	    echo "No such container ($1), or invalid ImageName.  Cannot upgrade."
+	    exit 1;
+	fi
+	podman stop "$1"
+	podman pull "$img" || (echo "Failed fetching $img, check your network (settings)."; exit 1)
+	"/var/lib/containers/active/${1}.sh" || (echo "Failed recreating container $1"; exit 1)
+	echo "Container $1 recreated, restart with 'container start $1'"
+	;;
     volume)
 	cmd=$1
 	shift

package/execd/execd.conf

@@ -1,2 +1,2 @@
 service log:prio:local1.err,tag:container \
-	[2345] execd /run/containers/queue /var/lib/containers/done -- Container job runner
+	[2345] execd /run/containers/queue /var/lib/containers/active -- Container job runner

package/execd/tmpfiles.conf

@@ -1,5 +1,5 @@
 d  /run/containers/args		0700 - -
-d  /var/lib/containers/done	0700 - -
+d  /var/lib/containers/active	0700 - -
 d  /run/containers/inbox	0700 - -
 d  /run/containers/queue	0700 - -
 d  /run/cni			0755 - -

src/confd/src/infix-containers.c

@@ -19,7 +19,7 @@
 #define  CFG_XPATH    "/infix-containers:container"
 #define  INBOX_QUEUE  "/run/containers/inbox"
 #define  JOB_QUEUE    "/run/containers/queue"
-#define  DONE_QUEUE   "/var/lib/containers/done"
+#define  ACTIVE_QUEUE "/var/lib/containers/active"
 #define  LOGGER       "logger -t container -p local1.notice"
 
 static const struct srx_module_requirement reqs[] = {
@@ -231,13 +231,13 @@ void infix_containers_launch(void)
 	}
 
 	while ((d = readdir(dir))) {
+		char curr[strlen(ACTIVE_QUEUE) + strlen(d->d_name) + 2];
 		char next[strlen(INBOX_QUEUE) + strlen(d->d_name) + 2];
-		char curr[strlen(DONE_QUEUE) + strlen(d->d_name) + 2];
 
+		snprintf(curr, sizeof(curr), "%s/%s", ACTIVE_QUEUE, d->d_name);
 		snprintf(next, sizeof(next), "%s/%s", INBOX_QUEUE, d->d_name);
-		snprintf(curr, sizeof(curr), "%s/%s", DONE_QUEUE, d->d_name);
 		if (!systemf("cmp %s %s", curr, next)) {
-			ERRNO("New job %s is already done, no changes, skipping.", next);
+			ERRNO("New job %s is already active, no changes, skipping.", next);
 			systemf("initctl -nbq cond set container:$(basename %s .sh)", d->d_name);
 			remove(next);
 			continue;

src/klish-plugin-infix/xml/infix.xml

@@ -245,6 +245,13 @@
     <PARAM name="name" ptype="/CONTAINERS" help="Container name" />
     <ACTION sym="script" out="tty" interrupt="true">container stop $KLISH_PARAM_name</ACTION>
   </COMMAND>
+
+  <COMMAND name="upgrade" help="Upgrade image of a container (writable layer is lost!)">
+    <PARAM name="name" ptype="/CONTAINERS" help="Container name" />
+    <ACTION sym="script" out="tty" interrupt="true">
+      container upgrade $KLISH_PARAM_name
+    </ACTION>
+  </COMMAND>
 </COMMAND>
 
 <COMMAND name="copy" help="Copy configuration, e.g., copy running-config startup-config">