From e770b7204bf80b0a6b019bdc9cbfa050cd735e4e Mon Sep 17 00:00:00 2001
From: Vincent Bernat <vincent@bernat.im>
Date: Sun, 4 Jan 2015 18:24:29 +0100
Subject: [PATCH] lldp: send a shutdown LLDPDU on exit

With the previous commit, it is now easy to send a shutdown LLPDU when
exiting lldpd. Let's do that.
---
 src/daemon/lldp.c  |  8 +++++---
 src/daemon/lldpd.c | 19 +++++++++++++++++++
 src/daemon/lldpd.h |  1 +
 3 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/src/daemon/lldp.c b/src/daemon/lldp.c
index 0e6220e2..5b0e4771 100644
--- a/src/daemon/lldp.c
+++ b/src/daemon/lldp.c
@@ -469,12 +469,14 @@ toobig:
 	return E2BIG;
 }
 
-/* Send a shutdown LLDPDU. Should be called only if we have a previously sent
- * LLDPDU. */
-static int
+/* Send a shutdown LLDPDU. */
+int
 lldp_send_shutdown(struct lldpd *global,
     struct lldpd_hardware *hardware)
 {
+	if (hardware->h_lchassis_previous_id == NULL ||
+	    hardware->h_lport_previous_id == NULL)
+		return 0;
 	return _lldp_send(global, hardware,
 	    hardware->h_lchassis_previous_id_subtype,
 	    hardware->h_lchassis_previous_id,
diff --git a/src/daemon/lldpd.c b/src/daemon/lldpd.c
index 8e97fe86..153514be 100644
--- a/src/daemon/lldpd.c
+++ b/src/daemon/lldpd.c
@@ -906,6 +906,21 @@ lldpd_recv(struct lldpd *cfg, struct lldpd_hardware *hardware, int fd)
 	free(buffer);
 }
 
+static void
+lldpd_send_shutdown(struct lldpd_hardware *hardware)
+{
+	struct lldpd *cfg = hardware->h_cfg;
+	if (cfg->g_config.c_receiveonly || cfg->g_config.c_paused) return;
+	if ((hardware->h_flags & IFF_RUNNING) == 0)
+		return;
+
+	/* It's safe to call `lldp_send_shutdown()` because shutdown LLDPU will
+	 * only be emitted if LLDP was sent on that port. */
+	if (lldp_send_shutdown(hardware->h_cfg, hardware) != 0)
+		log_warnx("send", "unable to send shutdown LLDPDU on %s",
+		    hardware->h_ifname);
+}
+
 void
 lldpd_send(struct lldpd_hardware *hardware)
 {
@@ -1120,6 +1135,10 @@ lldpd_exit(struct lldpd *cfg)
 {
 	struct lldpd_hardware *hardware, *hardware_next;
 	log_debug("main", "exit lldpd");
+
+	TAILQ_FOREACH(hardware, &cfg->g_hardware, h_entries)
+		lldpd_send_shutdown(hardware);
+
 	close(cfg->g_ctl);
 	priv_ctl_cleanup(cfg->g_ctlname);
 	log_debug("main", "cleanup hardware information");
diff --git a/src/daemon/lldpd.h b/src/daemon/lldpd.h
index f5810676..9f986f31 100644
--- a/src/daemon/lldpd.h
+++ b/src/daemon/lldpd.h
@@ -160,6 +160,7 @@ void	 levent_schedule_cleanup(struct lldpd *);
 int	 levent_make_socket_nonblocking(int);
 
 /* lldp.c */
+int	 lldp_send_shutdown(PROTO_SEND_SIG);
 int	 lldp_send(PROTO_SEND_SIG);
 int	 lldp_decode(PROTO_DECODE_SIG);
 
-- 
2.39.5