Performance improvement: Use std::list instead of std::vector for request_media, Server::getModNames, Environment::m_simple_objects.

* Also remove unused Server::m_modspaths

src/client.cpp

@@ -778,7 +778,7 @@ void Client::deletingPeer(con::Peer *peer, bool timeout)
 		string name
 	}
 */
-void Client::request_media(const std::list<std::string> &file_requests)
+void Client::request_media(const std::vector<std::string> &file_requests)
 {
 	std::ostringstream os(std::ios_base::binary);
 	writeU16(os, TOSERVER_REQUEST_MEDIA);
@@ -790,7 +790,7 @@ void Client::request_media(const std::list<std::string> &file_requests)
 
 	*pkt << (u16) (file_requests_size & 0xFFFF);
 
-	for(std::list<std::string>::const_iterator i = file_requests.begin();
+	for(std::vector<std::string>::const_iterator i = file_requests.begin();
 			i != file_requests.end(); ++i) {
 		*pkt << (*i);
 	}

src/client.h

@@ -516,7 +516,7 @@ class Client : public con::PeerHandler, public InventoryManager, public IGameDef
 	// Insert a media file appropriately into the appropriate manager
 	bool loadMedia(const std::string &data, const std::string &filename);
 	// Send a request for conventional media transfer
-	void request_media(const std::list<std::string> &file_requests);
+	void request_media(const std::vector<std::string> &file_requests);
 	// Send a notification that no conventional media transfer is needed
 	void received_media();
 

src/clientmedia.cpp

@@ -488,7 +488,7 @@ void ClientMediaDownloader::startConventionalTransfers(Client *client)
 	if (m_uncached_received_count != m_uncached_count) {
 		// Some media files have not been received yet, use the
 		// conventional slow method (minetest protocol) to get them
-		std::list<std::string> file_requests;
+		std::vector<std::string> file_requests;
 		for (std::map<std::string, FileStatus*>::iterator
 				it = m_files.begin();
 				it != m_files.end(); ++it) {

src/environment.cpp

@@ -2025,9 +2025,8 @@ ClientEnvironment::~ClientEnvironment()
 		delete i->second;
 	}
 
-	for(std::list<ClientSimpleObject*>::iterator
+	for(std::vector<ClientSimpleObject*>::iterator
-			i = m_simple_objects.begin(); i != m_simple_objects.end(); ++i)
+			i = m_simple_objects.begin(); i != m_simple_objects.end(); ++i) {
-	{
 		delete *i;
 	}
 
@@ -2382,11 +2381,10 @@ void ClientEnvironment::step(float dtime)
 		Step and handle simple objects
 	*/
 	g_profiler->avg("CEnv: num of simple objects", m_simple_objects.size());
-	for(std::list<ClientSimpleObject*>::iterator
+	for(std::vector<ClientSimpleObject*>::iterator
-			i = m_simple_objects.begin(); i != m_simple_objects.end();)
+			i = m_simple_objects.begin(); i != m_simple_objects.end();) {
-	{
 		ClientSimpleObject *simple = *i;
-		std::list<ClientSimpleObject*>::iterator cur = i;
+		std::vector<ClientSimpleObject*>::iterator cur = i;
 		++i;
 		simple->step(dtime);
 		if(simple->m_to_be_removed){

src/environment.h

@@ -521,7 +521,7 @@ class ClientEnvironment : public Environment
 	IGameDef *m_gamedef;
 	IrrlichtDevice *m_irr;
 	std::map<u16, ClientActiveObject*> m_active_objects;
-	std::list<ClientSimpleObject*> m_simple_objects;
+	std::vector<ClientSimpleObject*> m_simple_objects;
 	std::list<ClientEnvEvent> m_client_event_queue;
 	IntervalLimiter m_active_object_light_update_interval;
 	IntervalLimiter m_lava_hurt_interval;

src/script/lua_api/l_server.cpp

@@ -367,13 +367,14 @@ int ModApiServer::l_get_modnames(lua_State *L)
 	NO_MAP_LOCK_REQUIRED;
 
 	// Get a list of mods
-	std::list<std::string> mods_unsorted, mods_sorted;
+	std::vector<std::string> mods_unsorted;
+	std::list<std::string> mods_sorted;
 	getServer(L)->getModNames(mods_unsorted);
 
 	// Take unsorted items from mods_unsorted and sort them into
 	// mods_sorted; not great performance but the number of mods on a
 	// server will likely be small.
-	for(std::list<std::string>::iterator i = mods_unsorted.begin();
+	for(std::vector<std::string>::iterator i = mods_unsorted.begin();
 			i != mods_unsorted.end(); ++i) {
 		bool added = false;
 		for(std::list<std::string>::iterator x = mods_sorted.begin();

src/server.cpp

@@ -3188,10 +3188,9 @@ const ModSpec* Server::getModSpec(const std::string &modname)
 	}
 	return NULL;
 }
-void Server::getModNames(std::list<std::string> &modlist)
+void Server::getModNames(std::vector<std::string> &modlist)
 {
-	for(std::vector<ModSpec>::iterator i = m_mods.begin(); i != m_mods.end(); i++)
+	for(std::vector<ModSpec>::iterator i = m_mods.begin(); i != m_mods.end(); i++) {
-	{
 		modlist.push_back(i->name);
 	}
 }

src/server.h

@@ -327,7 +327,7 @@ class Server : public con::PeerHandler, public MapEventReceiver,
 	IWritableCraftDefManager* getWritableCraftDefManager();
 
 	const ModSpec* getModSpec(const std::string &modname);
-	void getModNames(std::list<std::string> &modlist);
+	void getModNames(std::vector<std::string> &modlist);
 	std::string getBuiltinLuaPath();
 	inline std::string getWorldPath()
 			{ return m_path_world; }
@@ -588,9 +588,6 @@ class Server : public con::PeerHandler, public MapEventReceiver,
 		Random stuff
 	*/
 
-	// Mod parent directory paths
-	std::list<std::string> m_modspaths;
-
 	bool m_shutdown_requested;
 
 	/*