bgpd: Only build json for community when needed

Building a communities json object every time is
both expensive and memory wasteful.  Modify
code to only build the json object when needed.

Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>

7 files changed, 54 insertions, 30 deletions

diff --git a/bgpd/bgp_clist.c b/bgpd/bgp_clist.c
index f3bae9535..72b1098ed 100644
--- a/bgpd/bgp_clist.c
+++ b/bgpd/bgp_clist.c
@@ -438,7 +438,7 @@ static int community_regexp_match(struct community *com, regex_t *reg)
 	if (com == NULL || com->size == 0)
 		str = "";
 	else
-		str = community_str(com);
+		str = community_str(com, false);
 
 	/* Regular expression match.  */
 	if (regexec(reg, str, 0, NULL, 0) == 0)
diff --git a/bgpd/bgp_community.c b/bgpd/bgp_community.c
index b0f00d67d..7c83eaa09 100644
--- a/bgpd/bgp_community.c
+++ b/bgpd/bgp_community.c
@@ -169,7 +169,6 @@ struct community *community_uniq_sort(struct community *com)
 		return NULL;
 
 	new = community_new();
-	;
 	new->json = NULL;
 
 	for (i = 0; i < com->size; i++) {
@@ -195,7 +194,7 @@ struct community *community_uniq_sort(struct community *com)
    0xFFFF0000      "graceful-shutdown"
 
    For other values, "AS:VAL" format is used.  */
-static void set_community_string(struct community *com)
+static void set_community_string(struct community *com, bool make_json)
 {
 	int i;
 	char *str;
@@ -211,16 +210,20 @@ static void set_community_string(struct community *com)
 	if (!com)
 		return;
 
-	com->json = json_object_new_object();
-	json_community_list = json_object_new_array();
+	if (make_json) {
+		com->json = json_object_new_object();
+		json_community_list = json_object_new_array();
+	}
 
 	/* When communities attribute is empty.  */
 	if (com->size == 0) {
 		str = XMALLOC(MTYPE_COMMUNITY_STR, 1);
 		str[0] = '\0';
 
-		json_object_string_add(com->json, "string", "");
-		json_object_object_add(com->json, "list", json_community_list);
+		if (make_json) {
+			json_object_string_add(com->json, "string", "");
+			json_object_object_add(com->json, "list", json_community_list);
+		}
 		com->str = str;
 		return;
 	}
@@ -273,47 +276,61 @@ static void set_community_string(struct community *com)
 		case COMMUNITY_INTERNET:
 			strcpy(pnt, "internet");
 			pnt += strlen("internet");
-			json_string = json_object_new_string("internet");
-			json_object_array_add(json_community_list, json_string);
+			if (make_json) {
+				json_string = json_object_new_string("internet");
+				json_object_array_add(json_community_list, json_string);
+			}
 			break;
 		case COMMUNITY_NO_EXPORT:
 			strcpy(pnt, "no-export");
 			pnt += strlen("no-export");
-			json_string = json_object_new_string("noExport");
-			json_object_array_add(json_community_list, json_string);
+			if (make_json) {
+				json_string = json_object_new_string("noExport");
+				json_object_array_add(json_community_list, json_string);
+			}
 			break;
 		case COMMUNITY_NO_ADVERTISE:
 			strcpy(pnt, "no-advertise");
 			pnt += strlen("no-advertise");
-			json_string = json_object_new_string("noAdvertise");
-			json_object_array_add(json_community_list, json_string);
+			if (make_json) {
+				json_string = json_object_new_string("noAdvertise");
+				json_object_array_add(json_community_list, json_string);
+			}
 			break;
 		case COMMUNITY_LOCAL_AS:
 			strcpy(pnt, "local-AS");
 			pnt += strlen("local-AS");
-			json_string = json_object_new_string("localAs");
-			json_object_array_add(json_community_list, json_string);
+			if (make_json) {
+				json_string = json_object_new_string("localAs");
+				json_object_array_add(json_community_list, json_string);
+			}
 			break;
 		case COMMUNITY_GSHUT:
 			strcpy(pnt, "graceful-shutdown");
 			pnt += strlen("graceful-shutdown");
-			json_string = json_object_new_string("gracefulShutdown");
-			json_object_array_add(json_community_list, json_string);
+			if (make_json) {
+				json_string = json_object_new_string("gracefulShutdown");
+				json_object_array_add(json_community_list, json_string);
+			}
 			break;
 		default:
 			as = (comval >> 16) & 0xFFFF;
 			val = comval & 0xFFFF;
 			sprintf(pnt, "%u:%d", as, val);
-			json_string = json_object_new_string(pnt);
-			json_object_array_add(json_community_list, json_string);
+			if (make_json) {
+				json_string = json_object_new_string(pnt);
+				json_object_array_add(json_community_list, json_string);
+			}
 			pnt += strlen(pnt);
 			break;
 		}
 	}
 	*pnt = '\0';
 
-	json_object_string_add(com->json, "string", str);
-	json_object_object_add(com->json, "list", json_community_list);
+	if (make_json) {
+		json_object_string_add(com->json, "string", str);
+		json_object_object_add(com->json, "list", json_community_list);
+	}
 	com->str = str;
 }
 
@@ -338,7 +355,7 @@ struct community *community_intern(struct community *com)
 
 	/* Make string.  */
 	if (!find->str)
-		set_community_string(find);
+		set_community_string(find, false);
 
 	return find;
 }
@@ -396,13 +413,16 @@ struct community *community_dup(struct community *com)
 }
 
 /* Retrun string representation of communities attribute. */
-char *community_str(struct community *com)
+char *community_str(struct community *com, bool make_json)
 {
 	if (!com)
 		return NULL;
 
+	if (make_json && !com->json && com->str)
+		XFREE(MTYPE_COMMUNITY_STR, com->str);
+
 	if (!com->str)
-		set_community_string(com);
+		set_community_string(com, make_json);
 	return com->str;
 }
 
diff --git a/bgpd/bgp_community.h b/bgpd/bgp_community.h
index f728debdb..5016f132f 100644
--- a/bgpd/bgp_community.h
+++ b/bgpd/bgp_community.h
@@ -63,7 +63,7 @@ extern struct community *community_uniq_sort(struct community *);
 extern struct community *community_parse(u_int32_t *, u_short);
 extern struct community *community_intern(struct community *);
 extern void community_unintern(struct community **);
-extern char *community_str(struct community *);
+extern char *community_str(struct community *, bool make_json);
 extern unsigned int community_hash_make(struct community *);
 extern struct community *community_str2com(const char *);
 extern int community_match(const struct community *, const struct community *);
diff --git a/bgpd/bgp_debug.c b/bgpd/bgp_debug.c
index 6e16d5f45..45ac8e685 100644
--- a/bgpd/bgp_debug.c
+++ b/bgpd/bgp_debug.c
@@ -385,7 +385,8 @@ int bgp_dump_attr(struct attr *attr, char *buf, size_t size)
 
 	if (CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_COMMUNITIES)))
 		snprintf(buf + strlen(buf), size - strlen(buf),
-			 ", community %s", community_str(attr->community));
+			 ", community %s", community_str(attr->community,
+							 false));
 
 	if (CHECK_FLAG(attr->flag, ATTR_FLAG_BIT(BGP_ATTR_EXT_COMMUNITIES)))
 		snprintf(buf + strlen(buf), size - strlen(buf),
diff --git a/bgpd/bgp_route.c b/bgpd/bgp_route.c
index f0d91c366..ba75da459 100644
--- a/bgpd/bgp_route.c
+++ b/bgpd/bgp_route.c
@@ -7885,6 +7885,9 @@ void route_vty_out_detail(struct vty *vty, struct bgp *bgp, struct prefix *p,
 		/* Line 4 display Community */
 		if (attr->community) {
 			if (json_paths) {
+				if (!attr->community->json)
+					community_str(attr->community,
+						      true);
 				json_object_lock(attr->community->json);
 				json_object_object_add(json_path, "community",
 						       attr->community->json);
diff --git a/bgpd/bgp_routemap.c b/bgpd/bgp_routemap.c
index 45487aa00..cc8cfd550 100644
--- a/bgpd/bgp_routemap.c
+++ b/bgpd/bgp_routemap.c
@@ -3813,7 +3813,7 @@ DEFUN (set_community,
 	}
 
 	/* Set communites attribute string.  */
-	str = community_str(com);
+	str = community_str(com, false);
 
 	if (additive) {
 		argstr = XCALLOC(MTYPE_TMP,
diff --git a/bgpd/bgp_vty.c b/bgpd/bgp_vty.c
index db19835f8..40f706a64 100644
--- a/bgpd/bgp_vty.c
+++ b/bgpd/bgp_vty.c
@@ -10010,7 +10010,7 @@ static void community_show_all_iterator(struct hash_backet *backet,
 
 	com = (struct community *)backet->data;
 	vty_out(vty, "[%p] (%ld) %s\n", (void *)com, com->refcnt,
-		community_str(com));
+		community_str(com, false));
 }
 
 /* Show BGP's community internal data. */
@@ -12698,7 +12698,7 @@ static void community_list_show(struct vty *vty, struct community_list *list)
 			vty_out(vty, "    %s %s\n",
 				community_direct_str(entry->direct),
 				entry->style == COMMUNITY_LIST_STANDARD
-					? community_str(entry->u.com)
+					? community_str(entry->u.com, false)
 					: entry->config);
 	}
 }
@@ -13354,7 +13354,7 @@ static const char *community_list_config_str(struct community_entry *entry)
 		str = "";
 	else {
 		if (entry->style == COMMUNITY_LIST_STANDARD)
-			str = community_str(entry->u.com);
+			str = community_str(entry->u.com, false);
 		else
 			str = entry->config;
 	}