Revise dynamic_add_media API to better accomodate future changes

src/script/lua_api/l_server.cpp

@@ -452,19 +452,30 @@ int ModApiServer::l_sound_fade(lua_State *L)
 }
 
 // dynamic_add_media(filepath)
-int ModApiServer::l_dynamic_add_media(lua_State *L)
+int ModApiServer::l_dynamic_add_media_raw(lua_State *L)
 {
 	NO_MAP_LOCK_REQUIRED;
 
-	// Reject adding media before the server has started up
 	if (!getEnv(L))
 		throw LuaError("Dynamic media cannot be added before server has started up");
 
 	std::string filepath = readParam<std::string>(L, 1);
 	CHECK_SECURE_PATH(L, filepath.c_str(), false);
 
-	bool ok = getServer(L)->dynamicAddMedia(filepath);
-	lua_pushboolean(L, ok);
+	std::vector<RemotePlayer*> sent_to;
+	bool ok = getServer(L)->dynamicAddMedia(filepath, sent_to);
+	if (ok) {
+		// (see wrapper code in builtin)
+		lua_createtable(L, sent_to.size(), 0);
+		int i = 0;
+		for (RemotePlayer *player : sent_to) {
+			lua_pushstring(L, player->getName());
+			lua_rawseti(L, -2, ++i);
+		}
+	} else {
+		lua_pushboolean(L, false);
+	}
+
 	return 1;
 }
 
@@ -532,7 +543,7 @@ void ModApiServer::Initialize(lua_State *L, int top)
 	API_FCT(sound_play);
 	API_FCT(sound_stop);
 	API_FCT(sound_fade);
-	API_FCT(dynamic_add_media);
+	API_FCT(dynamic_add_media_raw);
 
 	API_FCT(get_player_information);
 	API_FCT(get_player_privs);

src/script/lua_api/l_server.h

@@ -71,7 +71,7 @@ private:
 	static int l_sound_fade(lua_State *L);
 
 	// dynamic_add_media(filepath)
-	static int l_dynamic_add_media(lua_State *L);
+	static int l_dynamic_add_media_raw(lua_State *L);
 
 	// get_player_privs(name, text)
 	static int l_get_player_privs(lua_State *L);

src/server.cpp

@@ -3465,7 +3465,8 @@ void Server::deleteParticleSpawner(const std::string &playername, u32 id)
 	SendDeleteParticleSpawner(peer_id, id);
 }
 
-bool Server::dynamicAddMedia(const std::string &filepath)
+bool Server::dynamicAddMedia(const std::string &filepath,
+	std::vector<RemotePlayer*> &sent_to)
 {
 	std::string filename = fs::GetFilenameFromPath(filepath.c_str());
 	if (m_media.find(filename) != m_media.end()) {
@@ -3485,9 +3486,17 @@ bool Server::dynamicAddMedia(const std::string &filepath)
 	pkt << raw_hash << filename << (bool) true;
 	pkt.putLongString(filedata);
 
-	auto client_ids = m_clients.getClientIDs(CS_DefinitionsSent);
-	for (session_t client_id : client_ids) {
+	m_clients.lock();
+	for (auto &pair : m_clients.getClientList()) {
+		if (pair.second->getState() < CS_DefinitionsSent)
+			continue;
+		if (pair.second->net_proto_version < 39)
+			continue;
+
+		if (auto player = m_env->getPlayer(pair.second->peer_id))
+			sent_to.emplace_back(player);
 		/*
+			FIXME: this is a very awful hack
 			The network layer only guarantees ordered delivery inside a channel.
 			Since the very next packet could be one that uses the media, we have
 			to push the media over ALL channels to ensure it is processed before
@@ -3496,9 +3505,10 @@ bool Server::dynamicAddMedia(const std::string &filepath)
 			- channel 1 (HUD)
 			- channel 0 (everything else: e.g. play_sound, object messages)
 		*/
-		m_clients.send(client_id, 1, &pkt, true);
-		m_clients.send(client_id, 0, &pkt, true);
+		m_clients.send(pair.second->peer_id, 1, &pkt, true);
+		m_clients.send(pair.second->peer_id, 0, &pkt, true);
 	}
+	m_clients.unlock();
 
 	return true;
 }

src/server.h

@@ -257,7 +257,7 @@ public:
 
 	void deleteParticleSpawner(const std::string &playername, u32 id);
 
-	bool dynamicAddMedia(const std::string &filepath);
+	bool dynamicAddMedia(const std::string &filepath, std::vector<RemotePlayer*> &sent_to);
 
 	ServerInventoryManager *getInventoryMgr() const { return m_inventory_mgr.get(); }
 	void sendDetachedInventory(Inventory *inventory, const std::string &name, session_t peer_id);