msg: Drop msg->tlv_count.

The field is redundant with the length tlv_list. Replace it with a function msg_tlv_count() instead. This iterates over the tlv_list. The computational overhead should be small, because the lists are very short and the tlv_count is only used in management paths (yet). Signed-off-by: Michael Walle <[email protected]>
JotusKuo · Jul 21, 2018 · 8f484e8 · 8f484e8
1 parent 427f1b3
commit 8f484e8
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Showing 5 changed files with 23 additions and 9 deletions.
diff --git a/clock.c b/clock.c
@@ -1319,7 +1319,7 @@ int clock_manage(struct clock *c, struct port *p, struct ptp_message *msg)
 	if (!cid_eq(tcid, &wildcard) && !cid_eq(tcid, &c->dds.clockIdentity)) {
 		return changed;
 	}
-	if (msg->tlv_count != 1) {
+	if (msg_tlv_count(msg) != 1) {
 		return changed;
 	}
 	mgt = (struct management_tlv *) msg->management.suffix;

diff --git a/msg.c b/msg.c
@@ -318,7 +318,6 @@ struct ptp_message *msg_duplicate(struct ptp_message *msg, int cnt)
 	memcpy(dup, msg, sizeof(*dup));
 	dup->refcnt = 1;
 	TAILQ_INIT(&dup->tlv_list);
-	dup->tlv_count = 0;
 
 	err = msg_post_recv(dup, cnt);
 	if (err) {
@@ -506,7 +505,19 @@ struct tlv_extra *msg_tlv_append(struct ptp_message *msg, int length)
 void msg_tlv_attach(struct ptp_message *msg, struct tlv_extra *extra)
 {
 	TAILQ_INSERT_TAIL(&msg->tlv_list, extra, list);
-	msg->tlv_count++;
+}
+
+int msg_tlv_count(struct ptp_message *msg)
+{
+	int count = 0;
+	struct tlv_extra *extra;
+
+	for (extra = TAILQ_FIRST(&msg->tlv_list);
+			extra != NULL;
+			extra = TAILQ_NEXT(extra, list))
+		count++;
+
+	return count;
 }
 
 const char *msg_type_string(int type)

diff --git a/msg.h b/msg.h
@@ -227,10 +227,6 @@ struct ptp_message {
 	 * pointers to the appended TLVs.
 	 */
 	TAILQ_HEAD(tlv_list, tlv_extra) tlv_list;
-	/**
-	 * Contains the number of TLVs in the suffix.
-	 */
-	int tlv_count;
 };
 
 /**
@@ -279,6 +275,13 @@ struct tlv_extra *msg_tlv_append(struct ptp_message *msg, int length);
  */
 void msg_tlv_attach(struct ptp_message *msg, struct tlv_extra *extra);
 
+/*
+ * Return the number of TLVs attached to a message.
+ * @param msg  A message obtained using @ref msg_allocate().
+ * @return     The number of attached TLVs.
+ */
+int msg_tlv_count(struct ptp_message *msg);
+
 /**
  * Obtain the transportSpecific field from a message.
  * @param m  Message to test.

diff --git a/phc2sys.c b/phc2sys.c
@@ -819,7 +819,7 @@ static int is_msg_mgt(struct ptp_message *msg)
 		return 0;
 	if (management_action(msg) != RESPONSE)
 		return 0;
-	if (msg->tlv_count != 1)
+	if (msg_tlv_count(msg) != 1)
 		return 0;
 	tlv = (struct TLV *) msg->management.suffix;
 	if (tlv->type == TLV_MANAGEMENT)

diff --git a/pmc.c b/pmc.c
@@ -80,7 +80,7 @@ static void pmc_show(struct ptp_message *msg, FILE *fp)
 	fprintf(fp, "\t%s seq %hu %s ",
 		pid2str(&msg->header.sourcePortIdentity),
 		msg->header.sequenceId, pmc_action_string(action));
-	if (msg->tlv_count != 1) {
+	if (msg_tlv_count(msg) != 1) {
 		goto out;
 	}
 	extra = TAILQ_FIRST(&msg->tlv_list);