[Net] Modularize multiplayer, expose MultiplayerAPI to extensions.

- RPC configurations are now dictionaries. - Script.get_rpc_methods renamed to Script.get_rpc_config. - Node.rpc[_id] and Callable.rpc now return an Error. - Refactor MultiplayerAPI to allow extension. - New MultiplayerAPI.rpc method with Array argument (for scripts). - Move the default MultiplayerAPI implementation to a module.
2025-11-04 12:00:25 +00:00 · 2022-07-12 23:12:42 +02:00
parent c3dc887c41
commit ca7d572908
80 changed files with 1819 additions and 1388 deletions
--- a/modules/multiplayer/scene_cache_interface.cpp
+++ b/modules/multiplayer/scene_cache_interface.cpp
@@ -0,0 +1,268 @@
+/*************************************************************************/
+/*  scene_cache_interface.cpp                                            */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2022 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2022 Godot Engine contributors (cf. AUTHORS.md).   */
+/*                                                                       */
+/* Permission is hereby granted, free of charge, to any person obtaining */
+/* a copy of this software and associated documentation files (the       */
+/* "Software"), to deal in the Software without restriction, including   */
+/* without limitation the rights to use, copy, modify, merge, publish,   */
+/* distribute, sublicense, and/or sell copies of the Software, and to    */
+/* permit persons to whom the Software is furnished to do so, subject to */
+/* the following conditions:                                             */
+/*                                                                       */
+/* The above copyright notice and this permission notice shall be        */
+/* included in all copies or substantial portions of the Software.       */
+/*                                                                       */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,       */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF    */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY  */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,  */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE     */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                */
+/*************************************************************************/
+
+#include "scene_cache_interface.h"
+
+#include "core/io/marshalls.h"
+#include "scene/main/node.h"
+#include "scene/main/window.h"
+
+#include "scene_multiplayer.h"
+
+void SceneCacheInterface::on_peer_change(int p_id, bool p_connected) {
+	if (p_connected) {
+		path_get_cache.insert(p_id, PathGetCache());
+	} else {
+		// Cleanup get cache.
+		path_get_cache.erase(p_id);
+		// Cleanup sent cache.
+		// Some refactoring is needed to make this faster and do paths GC.
+		for (const KeyValue<NodePath, PathSentCache> &E : path_send_cache) {
+			PathSentCache *psc = path_send_cache.getptr(E.key);
+			psc->confirmed_peers.erase(p_id);
+		}
+	}
+}
+
+void SceneCacheInterface::process_simplify_path(int p_from, const uint8_t *p_packet, int p_packet_len) {
+	Node *root_node = SceneTree::get_singleton()->get_root()->get_node(multiplayer->get_root_path());
+	ERR_FAIL_COND(!root_node);
+	ERR_FAIL_COND_MSG(p_packet_len < 38, "Invalid packet received. Size too small.");
+	int ofs = 1;
+
+	String methods_md5;
+	methods_md5.parse_utf8((const char *)(p_packet + ofs), 32);
+	ofs += 33;
+
+	int id = decode_uint32(&p_packet[ofs]);
+	ofs += 4;
+
+	String paths;
+	paths.parse_utf8((const char *)(p_packet + ofs), p_packet_len - ofs);
+
+	NodePath path = paths;
+
+	if (!path_get_cache.has(p_from)) {
+		path_get_cache[p_from] = PathGetCache();
+	}
+
+	Node *node = root_node->get_node(path);
+	ERR_FAIL_COND(node == nullptr);
+	const bool valid_rpc_checksum = multiplayer->get_rpc_md5(node) == methods_md5;
+	if (valid_rpc_checksum == false) {
+		ERR_PRINT("The rpc node checksum failed. Make sure to have the same methods on both nodes. Node path: " + path);
+	}
+
+	PathGetCache::NodeInfo ni;
+	ni.path = path;
+
+	path_get_cache[p_from].nodes[id] = ni;
+
+	// Encode path to send ack.
+	CharString pname = String(path).utf8();
+	int len = encode_cstring(pname.get_data(), nullptr);
+
+	Vector<uint8_t> packet;
+
+	packet.resize(1 + 1 + len);
+	packet.write[0] = SceneMultiplayer::NETWORK_COMMAND_CONFIRM_PATH;
+	packet.write[1] = valid_rpc_checksum;
+	encode_cstring(pname.get_data(), &packet.write[2]);
+
+	Ref<MultiplayerPeer> multiplayer_peer = multiplayer->get_multiplayer_peer();
+	ERR_FAIL_COND(multiplayer_peer.is_null());
+
+#ifdef DEBUG_ENABLED
+	multiplayer->profile_bandwidth("out", packet.size());
+#endif
+
+	multiplayer_peer->set_transfer_channel(0);
+	multiplayer_peer->set_transfer_mode(MultiplayerPeer::TRANSFER_MODE_RELIABLE);
+	multiplayer_peer->set_target_peer(p_from);
+	multiplayer_peer->put_packet(packet.ptr(), packet.size());
+}
+
+void SceneCacheInterface::process_confirm_path(int p_from, const uint8_t *p_packet, int p_packet_len) {
+	ERR_FAIL_COND_MSG(p_packet_len < 3, "Invalid packet received. Size too small.");
+
+	const bool valid_rpc_checksum = p_packet[1];
+
+	String paths;
+	paths.parse_utf8((const char *)&p_packet[2], p_packet_len - 2);
+
+	NodePath path = paths;
+
+	if (valid_rpc_checksum == false) {
+		ERR_PRINT("The rpc node checksum failed. Make sure to have the same methods on both nodes. Node path: " + path);
+	}
+
+	PathSentCache *psc = path_send_cache.getptr(path);
+	ERR_FAIL_COND_MSG(!psc, "Invalid packet received. Tries to confirm a path which was not found in cache.");
+
+	HashMap<int, bool>::Iterator E = psc->confirmed_peers.find(p_from);
+	ERR_FAIL_COND_MSG(!E, "Invalid packet received. Source peer was not found in cache for the given path.");
+	E->value = true;
+}
+
+Error SceneCacheInterface::_send_confirm_path(Node *p_node, NodePath p_path, PathSentCache *psc, const List<int> &p_peers) {
+	// Encode function name.
+	const CharString path = String(p_path).utf8();
+	const int path_len = encode_cstring(path.get_data(), nullptr);
+
+	// Extract MD5 from rpc methods list.
+	const String methods_md5 = multiplayer->get_rpc_md5(p_node);
+	const int methods_md5_len = 33; // 32 + 1 for the `0` that is added by the encoder.
+
+	Vector<uint8_t> packet;
+	packet.resize(1 + 4 + path_len + methods_md5_len);
+	int ofs = 0;
+
+	packet.write[ofs] = SceneMultiplayer::NETWORK_COMMAND_SIMPLIFY_PATH;
+	ofs += 1;
+
+	ofs += encode_cstring(methods_md5.utf8().get_data(), &packet.write[ofs]);
+
+	ofs += encode_uint32(psc->id, &packet.write[ofs]);
+
+	ofs += encode_cstring(path.get_data(), &packet.write[ofs]);
+
+	Ref<MultiplayerPeer> multiplayer_peer = multiplayer->get_multiplayer_peer();
+	ERR_FAIL_COND_V(multiplayer_peer.is_null(), ERR_BUG);
+
+#ifdef DEBUG_ENABLED
+	multiplayer->profile_bandwidth("out", packet.size() * p_peers.size());
+#endif
+
+	Error err = OK;
+	for (int peer_id : p_peers) {
+		multiplayer_peer->set_target_peer(peer_id);
+		multiplayer_peer->set_transfer_channel(0);
+		multiplayer_peer->set_transfer_mode(MultiplayerPeer::TRANSFER_MODE_RELIABLE);
+		err = multiplayer_peer->put_packet(packet.ptr(), packet.size());
+		ERR_FAIL_COND_V(err != OK, err);
+		// Insert into confirmed, but as false since it was not confirmed.
+		psc->confirmed_peers.insert(peer_id, false);
+	}
+	return err;
+}
+
+bool SceneCacheInterface::is_cache_confirmed(NodePath p_path, int p_peer) {
+	const PathSentCache *psc = path_send_cache.getptr(p_path);
+	ERR_FAIL_COND_V(!psc, false);
+	HashMap<int, bool>::ConstIterator F = psc->confirmed_peers.find(p_peer);
+	ERR_FAIL_COND_V(!F, false); // Should never happen.
+	return F->value;
+}
+
+int SceneCacheInterface::make_object_cache(Object *p_obj) {
+	Node *node = Object::cast_to<Node>(p_obj);
+	ERR_FAIL_COND_V(!node, -1);
+	NodePath for_path = multiplayer->get_root_path().rel_path_to(node->get_path());
+	// See if the path is cached.
+	PathSentCache *psc = path_send_cache.getptr(for_path);
+	if (!psc) {
+		// Path is not cached, create.
+		path_send_cache[for_path] = PathSentCache();
+		psc = path_send_cache.getptr(for_path);
+		psc->id = last_send_cache_id++;
+	}
+	return psc->id;
+}
+
+bool SceneCacheInterface::send_object_cache(Object *p_obj, int p_peer_id, int &r_id) {
+	Node *node = Object::cast_to<Node>(p_obj);
+	ERR_FAIL_COND_V(!node, false);
+
+	r_id = make_object_cache(p_obj);
+	ERR_FAIL_COND_V(r_id < 0, false);
+	NodePath for_path = multiplayer->get_root_path().rel_path_to(node->get_path());
+	PathSentCache *psc = path_send_cache.getptr(for_path);
+
+	bool has_all_peers = true;
+	List<int> peers_to_add; // If one is missing, take note to add it.
+
+	if (p_peer_id > 0) {
+		// Fast single peer check.
+		HashMap<int, bool>::Iterator F = psc->confirmed_peers.find(p_peer_id);
+		if (!F) {
+			peers_to_add.push_back(p_peer_id); // Need to also be notified.
+			has_all_peers = false;
+		} else if (!F->value) {
+			has_all_peers = false;
+		}
+	} else {
+		// Long and painful.
+		for (const int &E : multiplayer->get_connected_peers()) {
+			if (p_peer_id < 0 && E == -p_peer_id) {
+				continue; // Continue, excluded.
+			}
+			if (p_peer_id > 0 && E != p_peer_id) {
+				continue; // Continue, not for this peer.
+			}
+
+			HashMap<int, bool>::Iterator F = psc->confirmed_peers.find(E);
+			if (!F) {
+				peers_to_add.push_back(E); // Need to also be notified.
+				has_all_peers = false;
+			} else if (!F->value) {
+				has_all_peers = false;
+			}
+		}
+	}
+
+	if (peers_to_add.size()) {
+		_send_confirm_path(node, for_path, psc, peers_to_add);
+	}
+
+	return has_all_peers;
+}
+
+Object *SceneCacheInterface::get_cached_object(int p_from, uint32_t p_cache_id) {
+	Node *root_node = SceneTree::get_singleton()->get_root()->get_node(multiplayer->get_root_path());
+	ERR_FAIL_COND_V(!root_node, nullptr);
+	HashMap<int, PathGetCache>::Iterator E = path_get_cache.find(p_from);
+	ERR_FAIL_COND_V_MSG(!E, nullptr, vformat("No cache found for peer %d.", p_from));
+
+	HashMap<int, PathGetCache::NodeInfo>::Iterator F = E->value.nodes.find(p_cache_id);
+	ERR_FAIL_COND_V_MSG(!F, nullptr, vformat("ID %d not found in cache of peer %d.", p_cache_id, p_from));
+
+	PathGetCache::NodeInfo *ni = &F->value;
+	Node *node = root_node->get_node(ni->path);
+	if (!node) {
+		ERR_PRINT("Failed to get cached path: " + String(ni->path) + ".");
+	}
+	return node;
+}
+
+void SceneCacheInterface::clear() {
+	path_get_cache.clear();
+	path_send_cache.clear();
+	last_send_cache_id = 1;
+}