bgpd: neighbors received-routes/advertised-routes stringify changes

JSON object could lead to out-of-memory in scaled bgp
neighbors received-routes/advertised-routes setup.

Changes:

not use pretty print and stringify smaller json objects to reduce memory
usage
free memory after ouput of json object

Commands supported with this Json stringify:

```
show bgp vrf <vrf-id> neighbors <nbr-id> advertised-routes json
show bgp vrf <vrf-id> neighbors <nbr-id> advertised-routes detail json
show bgp vrf <vrf-id> neighbors <nbr-id> advertised-routes <prefix> json
show bgp vrf <vrf-id> neighbors <nbr-id> received-routes json
show bgp vrf <vrf-id> neighbors <nbr-id> received-routes detail json
show bgp vrf <vrf-id> neighbors <nbr-id> received-routes <prefix> json
```

Ticket:#3513253, #3513254

Issue:3513253, 3513254

Signed-off-by: Sindhu Parvathi Gopinathan's <sgopinathan@nvidia.com>

diff --git a/bgpd/bgp_route.c b/bgpd/bgp_route.c
index 17d25f8248b98a5b01d23ee436f180fa90843455..35b9a1f90637da1d62cdfcf0dc7588526cb43ccd 100644 (file)
--- a/bgpd/bgp_route.c
+++ b/bgpd/bgp_route.c
@@ -14879,6 +14879,8 @@ static int peer_adj_routes(struct vty *vty, struct peer *peer, afi_t afi,
        json_object *json = NULL;
        json_object *json_ar = NULL;
        bool use_json = CHECK_FLAG(show_flags, BGP_SHOW_OPT_JSON);
+       bool first = true;
+       struct update_subgroup *subgrp;
 
        /* Init BGP headers here so they're only displayed once
         * even if 'table' is 2-tier (MPLS_VPN, ENCAP, EVPN).
@@ -14947,6 +14949,28 @@ static int peer_adj_routes(struct vty *vty, struct peer *peer, afi_t afi,
        else
                table = bgp->rib[afi][safi];
 
+       subgrp = peer_subgroup(peer, afi, safi);
+       if (use_json) {
+               if (type == bgp_show_adj_route_advertised || type == bgp_show_adj_route_received) {
+                       if (header1) {
+                               int version = table ? table->version : 0;
+                               vty_out(vty, "\"bgpTableVersion\":%d", version);
+                               vty_out(vty, ",\"bgpLocalRouterId\":\"%pI4\"", &bgp->router_id);
+                               vty_out(vty, ",\"defaultLocPrf\":%u", bgp->default_local_pref);
+                               vty_out(vty, ",\"localAS\":%u", bgp->as);
+                               if (type == bgp_show_adj_route_advertised && subgrp &&
+                                   CHECK_FLAG(subgrp->sflags, SUBGRP_STATUS_DEFAULT_ORIGINATE))
+                                       vty_out(vty, ",\"bgpOriginatingDefaultNetwork\":\"%s\"",
+                                               (afi == AFI_IP) ? "0.0.0.0/0" : "::/0");
+                       }
+
+                       if (type == bgp_show_adj_route_advertised)
+                               vty_out(vty, ",\"advertisedRoutes\": ");
+                       if (type == bgp_show_adj_route_received)
+                               vty_out(vty, ",\"receivedRoutes\": ");
+               }
+       }
+
        if ((safi == SAFI_MPLS_VPN) || (safi == SAFI_ENCAP)
            || (safi == SAFI_EVPN)) {
 
@@ -14965,6 +14989,7 @@ static int peer_adj_routes(struct vty *vty, struct peer *peer, afi_t afi,
                                json_routes = json_object_new_object();
 
                        const struct prefix_rd *prd;
+
                        prd = (const struct prefix_rd *)bgp_dest_get_prefix(
                                dest);
 
@@ -14978,34 +15003,56 @@ static int peer_adj_routes(struct vty *vty, struct peer *peer, afi_t afi,
                                       &filtered_count_per_rd);
 
                        /* Don't include an empty RD in the output! */
-                       if (json_routes && (output_count_per_rd > 0))
-                               json_object_object_add(json_ar, rd_str,
-                                                      json_routes);
+                       if (json_routes && (output_count_per_rd > 0) && use_json) {
+                               if (type == bgp_show_adj_route_advertised ||
+                                   type == bgp_show_adj_route_received) {
+                                       if (first) {
+                                               vty_out(vty, "\"%s\":", rd_str);
+                                               first = false;
+                                       } else {
+                                               vty_out(vty, ",\"%s\":", rd_str);
+                                       }
+                                       vty_json_no_pretty(vty, json_routes);
+                               } else {
+                                       json_object_object_add(json_ar, rd_str, json_routes);
+                               }
+                       }
 
                        output_count += output_count_per_rd;
                        filtered_count += filtered_count_per_rd;
                }
-       } else
+       } else {
                show_adj_route(vty, peer, table, afi, safi, type, rmap_name,
                               json, json_ar, show_flags, &header1, &header2,
                               rd_str, match, &output_count, &filtered_count);
 
+               if (use_json) {
+                       if (type == bgp_show_adj_route_advertised ||
+                           type == bgp_show_adj_route_received) {
+                               vty_json_no_pretty(vty, json_ar);
+                       }
+               }
+       }
+
        if (use_json) {
-               if (type == bgp_show_adj_route_advertised)
-                       json_object_object_add(json, "advertisedRoutes",
-                                              json_ar);
-               else
+               if (type == bgp_show_adj_route_advertised || type == bgp_show_adj_route_received) {
+                       vty_out(vty, ",\"totalPrefixCounter\":%lu", output_count);
+                       vty_out(vty, ",\"filteredPrefixCounter\":%lu", filtered_count);
+                       json_object_free(json);
+               } else {
+                       /* for bgp_show_adj_route_filtered & bgp_show_adj_route_bestpath type */
                        json_object_object_add(json, "receivedRoutes", json_ar);
-               json_object_int_add(json, "totalPrefixCounter", output_count);
-               json_object_int_add(json, "filteredPrefixCounter",
-                                   filtered_count);
-
-                /*
-                 * This is an extremely expensive operation at scale
-                 * and non-pretty reduces memory footprint significantly.
-                 */
-                vty_json_no_pretty(vty, json);
-        } else if (output_count > 0) {
+                       json_object_int_add(json, "totalPrefixCounter", output_count);
+                       json_object_int_add(json, "filteredPrefixCounter", filtered_count);
+               }
+
+               /*
+                * This is an extremely expensive operation at scale
+                * and non-pretty reduces memory footprint significantly.
+                */
+               if ((type != bgp_show_adj_route_advertised) && (type != bgp_show_adj_route_received))
+                       vty_json_no_pretty(vty, json);
+       } else if (output_count > 0) {
                if (!match && filtered_count > 0)
                        vty_out(vty,
                                "\nTotal number of prefixes %ld (%ld filtered)\n",
@@ -15108,6 +15155,7 @@ DEFPY(show_ip_bgp_instance_neighbor_advertised_route,
        uint16_t show_flags = 0;
        struct listnode *node;
        struct bgp *abgp;
+       int ret;
 
        if (detail || prefix_str)
                SET_FLAG(show_flags, BGP_SHOW_OPT_ROUTES_DETAIL);
@@ -15149,9 +15197,22 @@ DEFPY(show_ip_bgp_instance_neighbor_advertised_route,
        else if (argv_find(argv, argc, "filtered-routes", &idx))
                type = bgp_show_adj_route_filtered;
 
-       if (!all)
-               return peer_adj_routes(vty, peer, afi, safi, type, route_map,
-                                      prefix_str ? prefix : NULL, show_flags);
+       if (!all) {
+               if (uj)
+                       if (type == bgp_show_adj_route_advertised ||
+                           type == bgp_show_adj_route_received)
+                               vty_out(vty, "{\n");
+
+               ret = peer_adj_routes(vty, peer, afi, safi, type, route_map,
+                                     prefix_str ? prefix : NULL, show_flags);
+               if (uj)
+                       if (type == bgp_show_adj_route_advertised ||
+                           type == bgp_show_adj_route_received)
+                               vty_out(vty, "}\n");
+
+               return ret;
+       }
+
        if (uj)
                vty_out(vty, "{\n");