godot/modules/websocket/websocket_multiplayer_peer.cpp
2021-09-30 15:09:12 -06:00

291 lines
9.5 KiB
C++

/*************************************************************************/
/* websocket_multiplayer_peer.cpp */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur. */
/* Copyright (c) 2014-2021 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 "websocket_multiplayer_peer.h"
#include "core/os/os.h"
WebSocketMultiplayerPeer::WebSocketMultiplayerPeer() {
}
WebSocketMultiplayerPeer::~WebSocketMultiplayerPeer() {
_clear();
}
void WebSocketMultiplayerPeer::_clear() {
_peer_map.clear();
if (_current_packet.data != nullptr) {
memfree(_current_packet.data);
}
for (Packet &E : _incoming_packets) {
memfree(E.data);
E.data = nullptr;
}
_incoming_packets.clear();
}
void WebSocketMultiplayerPeer::_bind_methods() {
ClassDB::bind_method(D_METHOD("set_buffers", "input_buffer_size_kb", "input_max_packets", "output_buffer_size_kb", "output_max_packets"), &WebSocketMultiplayerPeer::set_buffers);
ClassDB::bind_method(D_METHOD("get_peer", "peer_id"), &WebSocketMultiplayerPeer::get_peer);
ADD_SIGNAL(MethodInfo("peer_packet", PropertyInfo(Variant::INT, "peer_source")));
}
//
// PacketPeer
//
int WebSocketMultiplayerPeer::get_available_packet_count() const {
ERR_FAIL_COND_V_MSG(!_is_multiplayer, 0, "Please use get_peer(ID).get_available_packet_count to get available packet count from peers when not using the MultiplayerAPI.");
return _incoming_packets.size();
}
Error WebSocketMultiplayerPeer::get_packet(const uint8_t **r_buffer, int &r_buffer_size) {
ERR_FAIL_COND_V_MSG(!_is_multiplayer, ERR_UNCONFIGURED, "Please use get_peer(ID).get_packet/var to communicate with peers when not using the MultiplayerAPI.");
r_buffer_size = 0;
if (_current_packet.data != nullptr) {
memfree(_current_packet.data);
_current_packet.data = nullptr;
}
ERR_FAIL_COND_V(_incoming_packets.size() == 0, ERR_UNAVAILABLE);
_current_packet = _incoming_packets.front()->get();
_incoming_packets.pop_front();
*r_buffer = _current_packet.data;
r_buffer_size = _current_packet.size;
return OK;
}
Error WebSocketMultiplayerPeer::put_packet(const uint8_t *p_buffer, int p_buffer_size) {
ERR_FAIL_COND_V_MSG(!_is_multiplayer, ERR_UNCONFIGURED, "Please use get_peer(ID).put_packet/var to communicate with peers when not using the MultiplayerAPI.");
Vector<uint8_t> buffer = _make_pkt(SYS_NONE, get_unique_id(), _target_peer, p_buffer, p_buffer_size);
if (is_server()) {
return _server_relay(1, _target_peer, &(buffer.ptr()[0]), buffer.size());
} else {
return get_peer(1)->put_packet(&(buffer.ptr()[0]), buffer.size());
}
}
//
// MultiplayerPeer
//
void WebSocketMultiplayerPeer::set_target_peer(int p_target_peer) {
_target_peer = p_target_peer;
}
int WebSocketMultiplayerPeer::get_packet_peer() const {
ERR_FAIL_COND_V_MSG(!_is_multiplayer, 1, "This function is not available when not using the MultiplayerAPI.");
ERR_FAIL_COND_V(_incoming_packets.size() == 0, 1);
return _incoming_packets.front()->get().source;
}
int WebSocketMultiplayerPeer::get_unique_id() const {
return _peer_id;
}
void WebSocketMultiplayerPeer::_send_sys(Ref<WebSocketPeer> p_peer, uint8_t p_type, int32_t p_peer_id) {
ERR_FAIL_COND(!p_peer.is_valid());
ERR_FAIL_COND(!p_peer->is_connected_to_host());
Vector<uint8_t> message = _make_pkt(p_type, 1, 0, (uint8_t *)&p_peer_id, 4);
p_peer->put_packet(&(message.ptr()[0]), message.size());
}
Vector<uint8_t> WebSocketMultiplayerPeer::_make_pkt(uint8_t p_type, int32_t p_from, int32_t p_to, const uint8_t *p_data, uint32_t p_data_size) {
Vector<uint8_t> out;
out.resize(PROTO_SIZE + p_data_size);
uint8_t *w = out.ptrw();
memcpy(&w[0], &p_type, 1);
memcpy(&w[1], &p_from, 4);
memcpy(&w[5], &p_to, 4);
memcpy(&w[PROTO_SIZE], p_data, p_data_size);
return out;
}
void WebSocketMultiplayerPeer::_send_add(int32_t p_peer_id) {
// First of all, confirm the ID!
_send_sys(get_peer(p_peer_id), SYS_ID, p_peer_id);
// Then send the server peer (which will trigger connection_succeded in client)
_send_sys(get_peer(p_peer_id), SYS_ADD, 1);
for (const KeyValue<int, Ref<WebSocketPeer>> &E : _peer_map) {
int32_t id = E.key;
if (p_peer_id == id) {
continue; // Skip the newly added peer (already confirmed)
}
// Send new peer to others
_send_sys(get_peer(id), SYS_ADD, p_peer_id);
// Send others to new peer
_send_sys(get_peer(p_peer_id), SYS_ADD, id);
}
}
void WebSocketMultiplayerPeer::_send_del(int32_t p_peer_id) {
for (const KeyValue<int, Ref<WebSocketPeer>> &E : _peer_map) {
int32_t id = E.key;
if (p_peer_id != id) {
_send_sys(get_peer(id), SYS_DEL, p_peer_id);
}
}
}
void WebSocketMultiplayerPeer::_store_pkt(int32_t p_source, int32_t p_dest, const uint8_t *p_data, uint32_t p_data_size) {
Packet packet;
packet.data = (uint8_t *)memalloc(p_data_size);
packet.size = p_data_size;
packet.source = p_source;
packet.destination = p_dest;
memcpy(packet.data, &p_data[PROTO_SIZE], p_data_size);
_incoming_packets.push_back(packet);
emit_signal(SNAME("peer_packet"), p_source);
}
Error WebSocketMultiplayerPeer::_server_relay(int32_t p_from, int32_t p_to, const uint8_t *p_buffer, uint32_t p_buffer_size) {
if (p_to == 1) {
return OK; // Will not send to self
} else if (p_to == 0) {
for (KeyValue<int, Ref<WebSocketPeer>> &E : _peer_map) {
if (E.key != p_from) {
E.value->put_packet(p_buffer, p_buffer_size);
}
}
return OK; // Sent to all but sender
} else if (p_to < 0) {
for (KeyValue<int, Ref<WebSocketPeer>> &E : _peer_map) {
if (E.key != p_from && E.key != -p_to) {
E.value->put_packet(p_buffer, p_buffer_size);
}
}
return OK; // Sent to all but sender and excluded
} else {
ERR_FAIL_COND_V(p_to == p_from, FAILED);
Ref<WebSocketPeer> peer_to = get_peer(p_to);
ERR_FAIL_COND_V(peer_to.is_null(), FAILED);
return peer_to->put_packet(p_buffer, p_buffer_size); // Sending to specific peer
}
}
void WebSocketMultiplayerPeer::_process_multiplayer(Ref<WebSocketPeer> p_peer, uint32_t p_peer_id) {
ERR_FAIL_COND(!p_peer.is_valid());
const uint8_t *in_buffer;
int size = 0;
int data_size = 0;
Error err = p_peer->get_packet(&in_buffer, size);
ERR_FAIL_COND(err != OK);
ERR_FAIL_COND(size < PROTO_SIZE);
data_size = size - PROTO_SIZE;
uint8_t type = 0;
uint32_t from = 0;
int32_t to = 0;
memcpy(&type, in_buffer, 1);
memcpy(&from, &in_buffer[1], 4);
memcpy(&to, &in_buffer[5], 4);
if (is_server()) { // Server can resend
ERR_FAIL_COND(type != SYS_NONE); // Only server sends sys messages
ERR_FAIL_COND(from != p_peer_id); // Someone is cheating
if (to == 1) { // This is for the server
_store_pkt(from, to, in_buffer, data_size);
} else if (to == 0) {
// Broadcast, for us too
_store_pkt(from, to, in_buffer, data_size);
} else if (to < 0) {
// All but one, for us if not excluded
if (_peer_id != -(int32_t)p_peer_id) {
_store_pkt(from, to, in_buffer, data_size);
}
}
// Relay if needed (i.e. "to" includes a peer that is not the server)
_server_relay(from, to, in_buffer, size);
} else {
if (type == SYS_NONE) { // Payload message
_store_pkt(from, to, in_buffer, data_size);
return;
}
// System message
ERR_FAIL_COND(data_size < 4);
int id = 0;
memcpy(&id, &in_buffer[PROTO_SIZE], 4);
switch (type) {
case SYS_ADD: // Add peer
_peer_map[id] = Ref<WebSocketPeer>();
emit_signal(SNAME("peer_connected"), id);
if (id == 1) { // We just connected to the server
emit_signal(SNAME("connection_succeeded"));
}
break;
case SYS_DEL: // Remove peer
_peer_map.erase(id);
emit_signal(SNAME("peer_disconnected"), id);
break;
case SYS_ID: // Hello, server assigned ID
_peer_id = id;
break;
default:
ERR_FAIL_MSG("Invalid multiplayer message.");
break;
}
}
}