improved efficiency of network code...

...by avoiding deep copy of every incoming config object

src/config.cpp

@@ -782,6 +782,13 @@ std::string config::hash() const
 	return std::string(hash_str);
 }
 
+void config::swap(config& cfg)
+{
+	values.swap(cfg.values);
+	children.swap(cfg.children);
+	ordered_children.swap(cfg.ordered_children);
+}
+
 bool operator==(const config& a, const config& b)
 {
 	if (a.values != b.values)

src/config.hpp

@@ -168,6 +168,9 @@ public:
 	//! Resets the translated values of all strings contained in this object
 	void reset_translation() const;
 
+	//this is a cheap O(1) operation
+	void swap(config& cfg);
+
 	//! All the attributes of this node.
 	string_map values;
 

src/network_worker.cpp

@@ -625,7 +625,7 @@ TCPsocket get_received_data(TCPsocket sock, config& cfg)
 		delete buf;
 		throw config::error(error);
 	} else {
-		cfg = (*itor)->config_buf;
+		cfg.swap((*itor)->config_buf);
 		const TCPsocket res = (*itor)->sock;
 		buffer* buf = *itor;
 		received_data_queue.erase(itor);