Destination cache update:

Fixed possible memory leak if cache reference count is updated in future.

Added API for clean Destination cache by given interface Id.

Updated Destination cache print also interface id.

source/ipv6_stack/ipv6_routing_table.c

@@ -96,7 +96,7 @@ static NS_LIST_DEFINE(ipv6_routing_table, ipv6_route_t, link);
 static ipv6_destination_t *ipv6_destination_lookup(const uint8_t *address, int8_t interface_id);
 static void ipv6_destination_cache_forget_router(ipv6_neighbour_cache_t *cache, const uint8_t neighbour_addr[16]);
 static void ipv6_destination_cache_forget_neighbour(const ipv6_neighbour_t *neighbour);
-static void ipv6_destination_release(ipv6_destination_t *dest);
+static bool ipv6_destination_release(ipv6_destination_t *dest);
 static void ipv6_route_table_remove_router(int8_t interface_id, const uint8_t *addr, ipv6_route_src_t source);
 static uint16_t total_metric(const ipv6_route_t *route);
 static uint8_t ipv6_route_table_count_source(int8_t interface_id, ipv6_route_src_t source);
@@ -863,7 +863,7 @@ void ipv6_destination_cache_print(route_print_fn_t *print_fn)
     print_fn("Destination Cache:");
     ns_list_foreach(ipv6_destination_t, entry, &ipv6_destination_cache) {
         ROUTE_PRINT_ADDR_STR_BUFFER_INIT(addr_str);
-        print_fn(" %s (life %u)", ROUTE_PRINT_ADDR_STR_FORMAT(addr_str, entry->destination), entry->lifetime);
+        print_fn(" %s (%d id) (life %u)", ROUTE_PRINT_ADDR_STR_FORMAT(addr_str, entry->destination), entry->interface_id, entry->lifetime);
 #ifdef HAVE_IPV6_ND
         if (entry->redirected) {
             print_fn("     Redirect %s%%%u", ROUTE_PRINT_ADDR_STR_FORMAT(addr_str, entry->redirect_addr), entry->interface_id);
@@ -939,7 +939,6 @@ ipv6_destination_t *ipv6_destination_lookup_or_create(const uint8_t *address, in
     if (!entry) {
         if (count > destination_cache_config.max_entries) {
             entry = ns_list_get_last(&ipv6_destination_cache);
-            ns_list_remove(&ipv6_destination_cache, entry);
             ipv6_destination_release(entry);
         }
 
@@ -1082,18 +1081,31 @@ void ipv6_destination_cache_forced_gc(bool full_gc)
      **/
     ns_list_foreach_reverse_safe(ipv6_destination_t, entry, &ipv6_destination_cache) {
         if (entry->lifetime == 0 || gc_count > destination_cache_config.long_term_entries || full_gc) {
-            ns_list_remove(&ipv6_destination_cache, entry);
+            if (ipv6_destination_release(entry)) {
+                gc_count--;
+            }
+        }
+    }
+}
+
+void ipv6_destination_cache_clean(int8_t interface_id)
+{
+    ns_list_foreach_reverse_safe(ipv6_destination_t, entry, &ipv6_destination_cache) {
+        if (entry->interface_id == interface_id) {
             ipv6_destination_release(entry);
-            gc_count--;
         }
     }
 }
 
-static void ipv6_destination_release(ipv6_destination_t *dest)
+static bool ipv6_destination_release(ipv6_destination_t *dest)
 {
     if (--dest->refcount == 0) {
+        ns_list_remove(&ipv6_destination_cache, dest);
+        tr_debug("Destination cache remove: %s", trace_ipv6(dest->destination));
         ns_dyn_mem_free(dest);
+        return true;
     }
+    return false;
 }
 
 static void ipv6_destination_cache_gc_periodic(void)
@@ -1137,9 +1149,11 @@ static void ipv6_destination_cache_gc_periodic(void)
      */
     ns_list_foreach_reverse_safe(ipv6_destination_t, entry, &ipv6_destination_cache) {
         if (entry->lifetime == 0 || gc_count > destination_cache_config.short_term_entries) {
-            ns_list_remove(&ipv6_destination_cache, entry);
-            ipv6_destination_release(entry);
-            if (--gc_count <= destination_cache_config.long_term_entries) {
+            if (ipv6_destination_release(entry)) {
+                gc_count--;
+            }
+
+            if (gc_count <= destination_cache_config.long_term_entries) {
                 break;
             }
         }

source/ipv6_stack/ipv6_routing_table.h

@@ -223,6 +223,7 @@ void ipv6_destination_cache_timer(uint8_t ticks);
 void ipv6_destination_redirect(const uint8_t *dest_addr, const uint8_t *sender_addr, const uint8_t *redirect_addr, int8_t interface_id, addrtype_t ll_type, const uint8_t *ll_address);
 #endif
 void ipv6_destination_cache_forced_gc(bool full_gc);
+void ipv6_destination_cache_clean(int8_t interface_id);
 
 /* Combined Routing Table (RFC 4191) and Prefix List (RFC 4861) */
 /* On-link prefixes have the on_link flag set and next_hop is unset */

test/nanostack/unittest/stub/ipv6_routing_table_stub.c

@@ -272,3 +272,8 @@ void ipv6_route_table_source_invalidated_reset(void)
 {
 
 }
+
+void ipv6_destination_cache_clean(int8_t interface_id)
+{
+
+}