Cluster: basic data structures for nodes black list.

src/redis.c

@@ -583,6 +583,18 @@ dictType clusterNodesDictType = {
     NULL                        /* val destructor */
 };
 
+/* Cluster re-addition blacklist. This maps node IDs to the time
+ * we can re-add this node. The goal is to avoid readding a removed
+ * node for some time. */
+dictType clusterNodesBlackListDictType = {
+    dictSdsCaseHash,            /* hash function */
+    NULL,                       /* key dup */
+    NULL,                       /* val dup */
+    dictSdsKeyCaseCompare,      /* key compare */
+    dictSdsDestructor,          /* key destructor */
+    NULL                        /* val destructor */
+};
+
 /* Migrate cache dict type. */
 dictType migrateCacheDictType = {
     dictSdsHash,                /* hash function */