From a367175b0d22bbf9818995c4155e170a4b64bb70 Mon Sep 17 00:00:00 2001
From: Richard Cochran <richardcochran@gmail.com>
Date: Sun, 7 Jul 2013 21:27:32 +0200
Subject: [PATCH] Throw a state decision event if the clock quality changes.

Management messages can cause a change in the clock quality. If this
happens, then it is time to run the Best Master Clock algorithm again.

Signed-off-by: Richard Cochran <richardcochran@gmail.com>
---
 clock.c | 26 +++++++++++++++-----------
 clock.h |  4 +++-
 port.c  |  3 ++-
 3 files changed, 20 insertions(+), 13 deletions(-)

diff --git a/clock.c b/clock.c
index c2795a1..f59e753 100644
--- a/clock.c
+++ b/clock.c
@@ -305,7 +305,7 @@ out:
 }
 
 static int clock_management_set(struct clock *c, struct port *p,
-				int id, struct ptp_message *req)
+				int id, struct ptp_message *req, int *changed)
 {
 	int respond = 0;
 	struct management_tlv *tlv;
@@ -324,6 +324,7 @@ static int clock_management_set(struct clock *c, struct port *p,
 		c->utc_offset = gsn->utc_offset;
 		c->time_flags = gsn->time_flags;
 		c->time_source = gsn->time_source;
+		*changed = 1;
 		respond = 1;
 		break;
 	}
@@ -791,9 +792,9 @@ static void clock_forward_mgmt_msg(struct clock *c, struct port *p, struct ptp_m
 	}
 }
 
-void clock_manage(struct clock *c, struct port *p, struct ptp_message *msg)
+int clock_manage(struct clock *c, struct port *p, struct ptp_message *msg)
 {
-	int i;
+	int changed = 0, i;
 	struct management_tlv *mgt;
 	struct ClockIdentity *tcid, wildcard = {
 		{0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff}
@@ -805,10 +806,10 @@ void clock_manage(struct clock *c, struct port *p, struct ptp_message *msg)
 	/* Apply this message to the local clock and ports. */
 	tcid = &msg->management.targetPortIdentity.clockIdentity;
 	if (!cid_eq(tcid, &wildcard) && !cid_eq(tcid, &c->dds.clockIdentity)) {
-		return;
+		return changed;
 	}
 	if (msg->tlv_count != 1) {
-		return;
+		return changed;
 	}
 	mgt = (struct management_tlv *) msg->management.suffix;
 
@@ -821,24 +822,24 @@ void clock_manage(struct clock *c, struct port *p, struct ptp_message *msg)
 	switch (management_action(msg)) {
 	case GET:
 		if (clock_management_get_response(c, p, mgt->id, msg))
-			return;
+			return changed;
 		break;
 	case SET:
 		if (mgt->length == 2 && mgt->id != NULL_MANAGEMENT) {
 			clock_management_send_error(p, msg, WRONG_LENGTH);
-			return;
+			return changed;
 		}
-		if (clock_management_set(c, p, mgt->id, msg))
-			return;
+		if (clock_management_set(c, p, mgt->id, msg, &changed))
+			return changed;
 		break;
 	case COMMAND:
 		if (mgt->length != 2) {
 			clock_management_send_error(p, msg, WRONG_LENGTH);
-			return;
+			return changed;
 		}
 		break;
 	default:
-		return;
+		return changed;
 	}
 
 	switch (mgt->id) {
@@ -883,6 +884,7 @@ void clock_manage(struct clock *c, struct port *p, struct ptp_message *msg)
 		}
 		break;
 	}
+	return changed;
 }
 
 struct parent_ds *clock_parent_ds(struct clock *c)
@@ -945,6 +947,8 @@ int clock_poll(struct clock *c)
 		k = N_CLOCK_PFD * i + j;
 		if (c->pollfd[k].revents & (POLLIN|POLLPRI)) {
 			event = port_event(c->port[i], j);
+			if (EV_STATE_DECISION_EVENT == event)
+				sde = 1;
 		}
 	}
 
diff --git a/clock.h b/clock.h
index 6fafc08..309f731 100644
--- a/clock.h
+++ b/clock.h
@@ -120,8 +120,10 @@ void clock_install_fda(struct clock *c, struct port *p, struct fdarray fda);
  * @param c    The clock instance.
  * @param p    The port on which the message arrived.
  * @param msg  A management message.
+ * @return     One if the management action caused a change that
+ *             implies a state decision event, zero otherwise.
  */
-void clock_manage(struct clock *c, struct port *p, struct ptp_message *msg);
+int clock_manage(struct clock *c, struct port *p, struct ptp_message *msg);
 
 /**
  * Obtain a clock's parent data set.
diff --git a/port.c b/port.c
index c4505d8..dda5cde 100644
--- a/port.c
+++ b/port.c
@@ -1980,7 +1980,8 @@ enum fsm_event port_event(struct port *p, int fd_index)
 	case SIGNALING:
 		break;
 	case MANAGEMENT:
-		clock_manage(p->clock, p, msg);
+		if (clock_manage(p->clock, p, msg))
+			event = EV_STATE_DECISION_EVENT;
 		break;
 	}