godot/modules/multiplayer/scene_multiplayer.cpp
Fabio Alessandrelli 7536d15fe3 [MP] Let MultiplayerAPI handle packet relaying and peer signaling.
MultiplayerPeer changes:

- Adds is_server_relay_supported virtual method

Informs the upper MultiplayerAPI layer if it can signal peers connected
to the server to other clients, and perform packet relaying among them.

- Adds get_packet_channel and get_packet_mode virtual methods

Allows the MultiplayerAPI to retrieve the channel and transfer modes to
use when relaying the last received packet.

SceneMultiplayerPeer changes:

- Implement peer signaling and packet relaying when the MultiplayerPeer
  advertise they are supported.

ENet, WebRTC, WebSocket changes:

- Removed custom code for relaying from WebSocket and ENet, and let it
  be handled by the upper layer.
- Update WebRTC to split create_client, create_server, and create_mesh,
  with the latter behaving like the old initialize with
  "server_compatibility = false", and the first two supporting the upper
  layer relaying protocol.
2022-10-27 18:08:58 +02:00

484 lines
19 KiB
C++

/*************************************************************************/
/* scene_multiplayer.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_multiplayer.h"
#include "core/debugger/engine_debugger.h"
#include "core/io/marshalls.h"
#include <stdint.h>
#ifdef DEBUG_ENABLED
#include "core/os/os.h"
#endif
#ifdef DEBUG_ENABLED
void SceneMultiplayer::profile_bandwidth(const String &p_inout, int p_size) {
if (EngineDebugger::is_profiling("multiplayer")) {
Array values;
values.push_back(p_inout);
values.push_back(OS::get_singleton()->get_ticks_msec());
values.push_back(p_size);
EngineDebugger::profiler_add_frame_data("multiplayer", values);
}
}
#endif
Error SceneMultiplayer::poll() {
if (!multiplayer_peer.is_valid() || multiplayer_peer->get_connection_status() == MultiplayerPeer::CONNECTION_DISCONNECTED) {
return ERR_UNCONFIGURED;
}
multiplayer_peer->poll();
if (!multiplayer_peer.is_valid()) { // It's possible that polling might have resulted in a disconnection, so check here.
return OK;
}
while (multiplayer_peer->get_available_packet_count()) {
int sender = multiplayer_peer->get_packet_peer();
const uint8_t *packet;
int len;
int channel = multiplayer_peer->get_packet_channel();
MultiplayerPeer::TransferMode mode = multiplayer_peer->get_packet_mode();
Error err = multiplayer_peer->get_packet(&packet, len);
ERR_FAIL_COND_V_MSG(err != OK, err, vformat("Error getting packet! %d", err));
if (len && (packet[0] & CMD_MASK) == NETWORK_COMMAND_SYS) {
// Sys messages are processed separately since they might call _process_packet themselves.
_process_sys(sender, packet, len, mode, channel);
} else {
remote_sender_id = sender;
_process_packet(sender, packet, len);
remote_sender_id = 0;
}
if (!multiplayer_peer.is_valid()) {
return OK; // It's also possible that a packet or RPC caused a disconnection, so also check here.
}
}
replicator->on_network_process();
return OK;
}
void SceneMultiplayer::clear() {
connected_peers.clear();
packet_cache.clear();
cache->clear();
relay_buffer->clear();
}
void SceneMultiplayer::set_root_path(const NodePath &p_path) {
ERR_FAIL_COND_MSG(!p_path.is_absolute() && !p_path.is_empty(), "SceneMultiplayer root path must be absolute.");
root_path = p_path;
}
NodePath SceneMultiplayer::get_root_path() const {
return root_path;
}
void SceneMultiplayer::set_multiplayer_peer(const Ref<MultiplayerPeer> &p_peer) {
if (p_peer == multiplayer_peer) {
return; // Nothing to do
}
ERR_FAIL_COND_MSG(p_peer.is_valid() && p_peer->get_connection_status() == MultiplayerPeer::CONNECTION_DISCONNECTED,
"Supplied MultiplayerPeer must be connecting or connected.");
if (multiplayer_peer.is_valid()) {
multiplayer_peer->disconnect("peer_connected", callable_mp(this, &SceneMultiplayer::_add_peer));
multiplayer_peer->disconnect("peer_disconnected", callable_mp(this, &SceneMultiplayer::_del_peer));
multiplayer_peer->disconnect("connection_succeeded", callable_mp(this, &SceneMultiplayer::_connected_to_server));
multiplayer_peer->disconnect("connection_failed", callable_mp(this, &SceneMultiplayer::_connection_failed));
multiplayer_peer->disconnect("server_disconnected", callable_mp(this, &SceneMultiplayer::_server_disconnected));
clear();
}
multiplayer_peer = p_peer;
if (multiplayer_peer.is_valid()) {
multiplayer_peer->connect("peer_connected", callable_mp(this, &SceneMultiplayer::_add_peer));
multiplayer_peer->connect("peer_disconnected", callable_mp(this, &SceneMultiplayer::_del_peer));
multiplayer_peer->connect("connection_succeeded", callable_mp(this, &SceneMultiplayer::_connected_to_server));
multiplayer_peer->connect("connection_failed", callable_mp(this, &SceneMultiplayer::_connection_failed));
multiplayer_peer->connect("server_disconnected", callable_mp(this, &SceneMultiplayer::_server_disconnected));
}
replicator->on_reset();
}
Ref<MultiplayerPeer> SceneMultiplayer::get_multiplayer_peer() {
return multiplayer_peer;
}
void SceneMultiplayer::_process_packet(int p_from, const uint8_t *p_packet, int p_packet_len) {
ERR_FAIL_COND_MSG(root_path.is_empty(), "Multiplayer root was not initialized. If you are using custom multiplayer, remember to set the root path via SceneMultiplayer.set_root_path before using it.");
ERR_FAIL_COND_MSG(p_packet_len < 1, "Invalid packet received. Size too small.");
#ifdef DEBUG_ENABLED
profile_bandwidth("in", p_packet_len);
#endif
// Extract the `packet_type` from the LSB three bits:
uint8_t packet_type = p_packet[0] & CMD_MASK;
switch (packet_type) {
case NETWORK_COMMAND_SIMPLIFY_PATH: {
cache->process_simplify_path(p_from, p_packet, p_packet_len);
} break;
case NETWORK_COMMAND_CONFIRM_PATH: {
cache->process_confirm_path(p_from, p_packet, p_packet_len);
} break;
case NETWORK_COMMAND_REMOTE_CALL: {
rpc->process_rpc(p_from, p_packet, p_packet_len);
} break;
case NETWORK_COMMAND_RAW: {
_process_raw(p_from, p_packet, p_packet_len);
} break;
case NETWORK_COMMAND_SPAWN: {
replicator->on_spawn_receive(p_from, p_packet, p_packet_len);
} break;
case NETWORK_COMMAND_DESPAWN: {
replicator->on_despawn_receive(p_from, p_packet, p_packet_len);
} break;
case NETWORK_COMMAND_SYNC: {
replicator->on_sync_receive(p_from, p_packet, p_packet_len);
} break;
default: {
ERR_FAIL_MSG("Invalid network command from " + itos(p_from));
} break;
}
}
Error SceneMultiplayer::send_command(int p_to, const uint8_t *p_packet, int p_packet_len) {
if (server_relay && get_unique_id() != 1 && p_to != 1 && multiplayer_peer->is_server_relay_supported()) {
// Send relay packet.
relay_buffer->seek(0);
relay_buffer->put_u8(NETWORK_COMMAND_SYS);
relay_buffer->put_u8(SYS_COMMAND_RELAY);
relay_buffer->put_32(p_to); // Set the destination.
relay_buffer->put_data(p_packet, p_packet_len);
multiplayer_peer->set_target_peer(1);
const Vector<uint8_t> data = relay_buffer->get_data_array();
return multiplayer_peer->put_packet(data.ptr(), relay_buffer->get_position());
}
if (p_to < 0) {
for (const int &pid : connected_peers) {
if (pid == -p_to) {
continue;
}
multiplayer_peer->set_target_peer(pid);
multiplayer_peer->put_packet(p_packet, p_packet_len);
}
return OK;
} else {
multiplayer_peer->set_target_peer(p_to);
return multiplayer_peer->put_packet(p_packet, p_packet_len);
}
}
void SceneMultiplayer::_process_sys(int p_from, const uint8_t *p_packet, int p_packet_len, MultiplayerPeer::TransferMode p_mode, int p_channel) {
ERR_FAIL_COND_MSG(p_packet_len < SYS_CMD_SIZE, "Invalid packet received. Size too small.");
uint8_t sys_cmd_type = p_packet[1];
int32_t peer = int32_t(decode_uint32(&p_packet[2]));
switch (sys_cmd_type) {
case SYS_COMMAND_ADD_PEER: {
ERR_FAIL_COND(!server_relay || !multiplayer_peer->is_server_relay_supported() || get_unique_id() == 1 || p_from != 1);
_add_peer(peer);
} break;
case SYS_COMMAND_DEL_PEER: {
ERR_FAIL_COND(!server_relay || !multiplayer_peer->is_server_relay_supported() || get_unique_id() == 1 || p_from != 1);
_del_peer(peer);
} break;
case SYS_COMMAND_RELAY: {
ERR_FAIL_COND(!server_relay || !multiplayer_peer->is_server_relay_supported());
ERR_FAIL_COND(p_packet_len < SYS_CMD_SIZE + 1);
const uint8_t *packet = p_packet + SYS_CMD_SIZE;
int len = p_packet_len - SYS_CMD_SIZE;
bool should_process = false;
if (get_unique_id() == 1) { // I am the server.
// Direct messages to server should not go through relay.
ERR_FAIL_COND(peer > 0 && !connected_peers.has(peer));
// Send relay packet.
relay_buffer->seek(0);
relay_buffer->put_u8(NETWORK_COMMAND_SYS);
relay_buffer->put_u8(SYS_COMMAND_RELAY);
relay_buffer->put_32(p_from); // Set the source.
relay_buffer->put_data(packet, len);
const Vector<uint8_t> data = relay_buffer->get_data_array();
multiplayer_peer->set_transfer_mode(p_mode);
multiplayer_peer->set_transfer_channel(p_channel);
if (peer > 0) {
multiplayer_peer->set_target_peer(peer);
multiplayer_peer->put_packet(data.ptr(), relay_buffer->get_position());
} else {
for (const int &P : connected_peers) {
// Not to sender, nor excluded.
if (P == p_from || (peer < 0 && P != -peer)) {
continue;
}
multiplayer_peer->set_target_peer(P);
multiplayer_peer->put_packet(data.ptr(), relay_buffer->get_position());
}
}
if (peer == 0 || peer == -1) {
should_process = true;
peer = p_from; // Process as the source.
}
} else {
ERR_FAIL_COND(p_from != 1); // Bug.
should_process = true;
}
if (should_process) {
remote_sender_id = peer;
_process_packet(peer, packet, len);
remote_sender_id = 0;
}
} break;
default: {
ERR_FAIL();
}
}
}
void SceneMultiplayer::_add_peer(int p_id) {
if (server_relay && get_unique_id() == 1 && multiplayer_peer->is_server_relay_supported()) {
// Notify others of connection, and send connected peers to newly connected one.
uint8_t buf[SYS_CMD_SIZE];
buf[0] = NETWORK_COMMAND_SYS;
buf[1] = SYS_COMMAND_ADD_PEER;
multiplayer_peer->set_transfer_channel(0);
multiplayer_peer->set_transfer_mode(MultiplayerPeer::TRANSFER_MODE_RELIABLE);
for (const int &P : connected_peers) {
// Send new peer to already connected.
encode_uint32(p_id, &buf[2]);
multiplayer_peer->set_target_peer(P);
multiplayer_peer->put_packet(buf, sizeof(buf));
// Send already connected to new peer.
encode_uint32(P, &buf[2]);
multiplayer_peer->set_target_peer(p_id);
multiplayer_peer->put_packet(buf, sizeof(buf));
}
}
connected_peers.insert(p_id);
cache->on_peer_change(p_id, true);
replicator->on_peer_change(p_id, true);
emit_signal(SNAME("peer_connected"), p_id);
}
void SceneMultiplayer::_del_peer(int p_id) {
if (server_relay && get_unique_id() == 1 && multiplayer_peer->is_server_relay_supported()) {
// Notify others of disconnection.
uint8_t buf[SYS_CMD_SIZE];
buf[0] = NETWORK_COMMAND_SYS;
buf[1] = SYS_COMMAND_DEL_PEER;
multiplayer_peer->set_transfer_channel(0);
multiplayer_peer->set_transfer_mode(MultiplayerPeer::TRANSFER_MODE_RELIABLE);
encode_uint32(p_id, &buf[2]);
for (const int &P : connected_peers) {
if (P == p_id) {
continue;
}
multiplayer_peer->set_target_peer(P);
multiplayer_peer->put_packet(buf, sizeof(buf));
}
}
replicator->on_peer_change(p_id, false);
cache->on_peer_change(p_id, false);
connected_peers.erase(p_id);
emit_signal(SNAME("peer_disconnected"), p_id);
}
void SceneMultiplayer::_connected_to_server() {
emit_signal(SNAME("connected_to_server"));
}
void SceneMultiplayer::_connection_failed() {
emit_signal(SNAME("connection_failed"));
}
void SceneMultiplayer::_server_disconnected() {
replicator->on_reset();
emit_signal(SNAME("server_disconnected"));
}
Error SceneMultiplayer::send_bytes(Vector<uint8_t> p_data, int p_to, MultiplayerPeer::TransferMode p_mode, int p_channel) {
ERR_FAIL_COND_V_MSG(p_data.size() < 1, ERR_INVALID_DATA, "Trying to send an empty raw packet.");
ERR_FAIL_COND_V_MSG(!multiplayer_peer.is_valid(), ERR_UNCONFIGURED, "Trying to send a raw packet while no multiplayer peer is active.");
ERR_FAIL_COND_V_MSG(multiplayer_peer->get_connection_status() != MultiplayerPeer::CONNECTION_CONNECTED, ERR_UNCONFIGURED, "Trying to send a raw packet via a multiplayer peer which is not connected.");
if (packet_cache.size() < p_data.size() + 1) {
packet_cache.resize(p_data.size() + 1);
}
const uint8_t *r = p_data.ptr();
packet_cache.write[0] = NETWORK_COMMAND_RAW;
memcpy(&packet_cache.write[1], &r[0], p_data.size());
multiplayer_peer->set_transfer_channel(p_channel);
multiplayer_peer->set_transfer_mode(p_mode);
return send_command(p_to, packet_cache.ptr(), p_data.size() + 1);
}
void SceneMultiplayer::_process_raw(int p_from, const uint8_t *p_packet, int p_packet_len) {
ERR_FAIL_COND_MSG(p_packet_len < 2, "Invalid packet received. Size too small.");
Vector<uint8_t> out;
int len = p_packet_len - 1;
out.resize(len);
{
uint8_t *w = out.ptrw();
memcpy(&w[0], &p_packet[1], len);
}
emit_signal(SNAME("peer_packet"), p_from, out);
}
int SceneMultiplayer::get_unique_id() {
ERR_FAIL_COND_V_MSG(!multiplayer_peer.is_valid(), 0, "No multiplayer peer is assigned. Unable to get unique ID.");
return multiplayer_peer->get_unique_id();
}
void SceneMultiplayer::set_refuse_new_connections(bool p_refuse) {
ERR_FAIL_COND_MSG(!multiplayer_peer.is_valid(), "No multiplayer peer is assigned. Unable to set 'refuse_new_connections'.");
multiplayer_peer->set_refuse_new_connections(p_refuse);
}
bool SceneMultiplayer::is_refusing_new_connections() const {
ERR_FAIL_COND_V_MSG(!multiplayer_peer.is_valid(), false, "No multiplayer peer is assigned. Unable to get 'refuse_new_connections'.");
return multiplayer_peer->is_refusing_new_connections();
}
Vector<int> SceneMultiplayer::get_peer_ids() {
ERR_FAIL_COND_V_MSG(!multiplayer_peer.is_valid(), Vector<int>(), "No multiplayer peer is assigned. Assume no peers are connected.");
Vector<int> ret;
for (const int &E : connected_peers) {
ret.push_back(E);
}
return ret;
}
void SceneMultiplayer::set_allow_object_decoding(bool p_enable) {
allow_object_decoding = p_enable;
}
bool SceneMultiplayer::is_object_decoding_allowed() const {
return allow_object_decoding;
}
String SceneMultiplayer::get_rpc_md5(const Object *p_obj) {
return rpc->get_rpc_md5(p_obj);
}
Error SceneMultiplayer::rpcp(Object *p_obj, int p_peer_id, const StringName &p_method, const Variant **p_arg, int p_argcount) {
return rpc->rpcp(p_obj, p_peer_id, p_method, p_arg, p_argcount);
}
Error SceneMultiplayer::object_configuration_add(Object *p_obj, Variant p_config) {
if (p_obj == nullptr && p_config.get_type() == Variant::NODE_PATH) {
set_root_path(p_config);
return OK;
}
MultiplayerSpawner *spawner = Object::cast_to<MultiplayerSpawner>(p_config.get_validated_object());
MultiplayerSynchronizer *sync = Object::cast_to<MultiplayerSynchronizer>(p_config.get_validated_object());
if (spawner) {
return replicator->on_spawn(p_obj, p_config);
} else if (sync) {
return replicator->on_replication_start(p_obj, p_config);
}
return ERR_INVALID_PARAMETER;
}
Error SceneMultiplayer::object_configuration_remove(Object *p_obj, Variant p_config) {
if (p_obj == nullptr && p_config.get_type() == Variant::NODE_PATH) {
ERR_FAIL_COND_V(root_path != p_config.operator NodePath(), ERR_INVALID_PARAMETER);
set_root_path(NodePath());
return OK;
}
MultiplayerSpawner *spawner = Object::cast_to<MultiplayerSpawner>(p_config.get_validated_object());
MultiplayerSynchronizer *sync = Object::cast_to<MultiplayerSynchronizer>(p_config.get_validated_object());
if (spawner) {
return replicator->on_despawn(p_obj, p_config);
}
if (sync) {
return replicator->on_replication_stop(p_obj, p_config);
}
return ERR_INVALID_PARAMETER;
}
void SceneMultiplayer::set_server_relay_enabled(bool p_enabled) {
ERR_FAIL_COND_MSG(multiplayer_peer.is_valid() && multiplayer_peer->get_connection_status() != MultiplayerPeer::CONNECTION_DISCONNECTED, "Cannot change the server relay option while the multiplayer peer is active.");
server_relay = p_enabled;
}
bool SceneMultiplayer::is_server_relay_enabled() const {
return server_relay;
}
void SceneMultiplayer::_bind_methods() {
ClassDB::bind_method(D_METHOD("set_root_path", "path"), &SceneMultiplayer::set_root_path);
ClassDB::bind_method(D_METHOD("get_root_path"), &SceneMultiplayer::get_root_path);
ClassDB::bind_method(D_METHOD("clear"), &SceneMultiplayer::clear);
ClassDB::bind_method(D_METHOD("set_refuse_new_connections", "refuse"), &SceneMultiplayer::set_refuse_new_connections);
ClassDB::bind_method(D_METHOD("is_refusing_new_connections"), &SceneMultiplayer::is_refusing_new_connections);
ClassDB::bind_method(D_METHOD("set_allow_object_decoding", "enable"), &SceneMultiplayer::set_allow_object_decoding);
ClassDB::bind_method(D_METHOD("is_object_decoding_allowed"), &SceneMultiplayer::is_object_decoding_allowed);
ClassDB::bind_method(D_METHOD("set_server_relay_enabled", "enabled"), &SceneMultiplayer::set_server_relay_enabled);
ClassDB::bind_method(D_METHOD("is_server_relay_enabled"), &SceneMultiplayer::is_server_relay_enabled);
ClassDB::bind_method(D_METHOD("send_bytes", "bytes", "id", "mode", "channel"), &SceneMultiplayer::send_bytes, DEFVAL(MultiplayerPeer::TARGET_PEER_BROADCAST), DEFVAL(MultiplayerPeer::TRANSFER_MODE_RELIABLE), DEFVAL(0));
ADD_PROPERTY(PropertyInfo(Variant::NODE_PATH, "root_path"), "set_root_path", "get_root_path");
ADD_PROPERTY(PropertyInfo(Variant::BOOL, "allow_object_decoding"), "set_allow_object_decoding", "is_object_decoding_allowed");
ADD_PROPERTY(PropertyInfo(Variant::BOOL, "refuse_new_connections"), "set_refuse_new_connections", "is_refusing_new_connections");
ADD_PROPERTY(PropertyInfo(Variant::BOOL, "server_relay"), "set_server_relay_enabled", "is_server_relay_enabled");
ADD_PROPERTY_DEFAULT("refuse_new_connections", false);
ADD_SIGNAL(MethodInfo("peer_packet", PropertyInfo(Variant::INT, "id"), PropertyInfo(Variant::PACKED_BYTE_ARRAY, "packet")));
}
SceneMultiplayer::SceneMultiplayer() {
relay_buffer.instantiate();
replicator = Ref<SceneReplicationInterface>(memnew(SceneReplicationInterface(this)));
rpc = Ref<SceneRPCInterface>(memnew(SceneRPCInterface(this)));
cache = Ref<SceneCacheInterface>(memnew(SceneCacheInterface(this)));
}
SceneMultiplayer::~SceneMultiplayer() {
clear();
}