search: combine callbacks in case of multiple equivalent puts

Author: aberaud

src/search.h

@@ -641,18 +641,20 @@ struct Dht::Search {
                     n->acked[value->id].req.reset();
                     n->probe_query.reset();
                 }
+            } else {
+                a_sr->callback = [
+                    cb1 = std::move(a_sr->callback),
+                    cb2 = std::move(callback)
+                ](bool success, const std::vector<std::shared_ptr<Node>>& nodes){
+                    if (cb1) cb1(success, nodes);
+                    if (cb2) cb2(success, nodes);
+                };
             }
             if (isAnnounced(value->id)) {
                 if (a_sr->callback)
                     a_sr->callback(true, {});
                 a_sr->callback = {};
-                if (callback)
-                    callback(true, {});
                 return;
-            } else {
-                if (a_sr->callback)
-                    a_sr->callback(false, {});
-                a_sr->callback = callback;
             }
         }
     }