From 6650f18b865043ac4980992b7c9be6e776db76b0 Mon Sep 17 00:00:00 2001
From: irungentoo <irungentoo@gmail.com>
Date: Mon, 12 Jan 2015 20:26:29 -0500
Subject: [PATCH] Attempted fix of Tox killing routers part 2.

Reduced drastically the number of ips the DHT pings by only pinging
nodes that would be included in one of the close lists.
---
 toxcore/DHT.c | 43 ++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 40 insertions(+), 3 deletions(-)

diff --git a/toxcore/DHT.c b/toxcore/DHT.c
index 919655a2..4a0863d3 100644
--- a/toxcore/DHT.c
+++ b/toxcore/DHT.c
@@ -647,6 +647,21 @@ static int cmp_dht_entry(const void *a, const void *b)
     return 0;
 }
 
+/* Is it ok to store node with client_id in client.
+ *
+ * return 0 if node can't be stored.
+ * return 1 if it can.
+ */
+static unsigned int store_node_ok(const Client_data *client, const uint8_t *client_id, const uint8_t *comp_client_id)
+{
+    if ((is_timeout(client->assoc4.timestamp, BAD_NODE_TIMEOUT) && is_timeout(client->assoc6.timestamp, BAD_NODE_TIMEOUT))
+            || (id_closest(comp_client_id, client->client_id, client_id) == 2)) {
+        return 1;
+    } else {
+        return 0;
+    }
+}
+
 /* Replace a first bad (or empty) node with this one
  *  or replace a possibly bad node (tests failed or not done yet)
  *  that is further than any other in the list
@@ -674,8 +689,7 @@ static int replace_all(   Client_data    *list,
 
     Client_data *client = &list[0];
 
-    if ((is_timeout(client->assoc4.timestamp, BAD_NODE_TIMEOUT) && is_timeout(client->assoc6.timestamp, BAD_NODE_TIMEOUT))
-            || (id_closest(comp_client_id, client->client_id, client_id) == 2)) {
+    if (store_node_ok(client, client_id, comp_client_id)) {
         IPPTsPng *ipptp_write = NULL;
         IPPTsPng *ipptp_clear = NULL;
 
@@ -704,6 +718,29 @@ static int replace_all(   Client_data    *list,
     return 0;
 }
 
+/* Check if the node obtained with a get_nodes with client_id should be pinged.
+ * NOTE: for best results call it after addto_lists;
+ *
+ * return 0 if the node should not be pinged.
+ * return 1 if it should.
+ */
+static unsigned int ping_node_from_getnodes_ok(DHT *dht, const uint8_t *client_id)
+{
+    if (store_node_ok(&dht->close_clientlist[0], client_id, dht->self_public_key)) {
+        return 1;
+    }
+
+    unsigned int i;
+
+    for (i = 0; i < dht->num_friends; ++i) {
+        if (store_node_ok(&dht->friends_list[i].client_list[0], client_id, dht->self_public_key)) {
+            return 1;
+        }
+    }
+
+    return 0;
+}
+
 /* Attempt to add client with ip_port and client_id to the friends client list
  * and close_clientlist.
  *
@@ -1091,7 +1128,7 @@ static int handle_sendnodes_ipv6(void *object, IP_Port source, const uint8_t *pa
     uint32_t i;
 
     for (i = 0; i < num_nodes; i++) {
-        if (ipport_isset(&plain_nodes[i].ip_port)) {
+        if (ipport_isset(&plain_nodes[i].ip_port) && ping_node_from_getnodes_ok(dht, plain_nodes[i].client_id)) {
             send_ping_request(dht->ping, plain_nodes[i].ip_port, plain_nodes[i].client_id);
             returnedip_ports(dht, plain_nodes[i].ip_port, plain_nodes[i].client_id, packet + 1);
         }