refactor: Make add_to_list non-recursive.

Author: iphydf

toxcore/DHT.c

@@ -606,27 +606,42 @@ bool add_to_list(
     Node_format *nodes_list, uint32_t length, const uint8_t pk[CRYPTO_PUBLIC_KEY_SIZE],
     const IP_Port *ip_port, const uint8_t cmp_pk[CRYPTO_PUBLIC_KEY_SIZE])
 {
-    for (uint32_t i = 0; i < length; ++i) {
-        Node_format *node = &nodes_list[i];
+    uint8_t pk_cur[CRYPTO_PUBLIC_KEY_SIZE];
+    memcpy(pk_cur, pk, CRYPTO_PUBLIC_KEY_SIZE);
+    IP_Port ip_port_cur = *ip_port;
 
-        if (id_closest(cmp_pk, node->public_key, pk) == 2) {
-            uint8_t pk_bak[CRYPTO_PUBLIC_KEY_SIZE];
-            memcpy(pk_bak, node->public_key, CRYPTO_PUBLIC_KEY_SIZE);
+    bool inserted = false;
+    bool done = false;
 
-            const IP_Port ip_port_bak = node->ip_port;
-            memcpy(node->public_key, pk, CRYPTO_PUBLIC_KEY_SIZE);
+    while (!done) {
+        done = true;
 
-            node->ip_port = *ip_port;
+        for (uint32_t i = 0; i < length; ++i) {
+            Node_format *node = &nodes_list[i];
 
-            if (i != length - 1) {
-                add_to_list(nodes_list, length, pk_bak, &ip_port_bak, cmp_pk);
-            }
+            if (id_closest(cmp_pk, node->public_key, pk_cur) == 2) {
+                uint8_t pk_bak[CRYPTO_PUBLIC_KEY_SIZE];
+                memcpy(pk_bak, node->public_key, CRYPTO_PUBLIC_KEY_SIZE);
 
-            return true;
+                const IP_Port ip_port_bak = node->ip_port;
+                memcpy(node->public_key, pk_cur, CRYPTO_PUBLIC_KEY_SIZE);
+
+                node->ip_port = ip_port_cur;
+
+                if (i == length - 1) {
+                    return true;
+                }
+
+                memcpy(pk_cur, pk_bak, CRYPTO_PUBLIC_KEY_SIZE);
+                ip_port_cur = ip_port_bak;
+                done = false;
+                inserted = true;
+                break;
+            }
         }
     }
 
-    return false;
+    return inserted;
 }
 
 /**