Cppcheck report - Godot - branch: 3.x, commit: cd92ad0f69a842d94dc2d56f83cbd8f724ed2959 (2024-12-15): modules/enet/networked_multiplayer_enet.cpp

/**************************************************************************/
/*  networked_multiplayer_enet.cpp                                        */
/**************************************************************************/
/*                         This file is part of:                          */
/*                             GODOT ENGINE                               */
/*                        https://godotengine.org                         */
/**************************************************************************/
/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
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/* Permission is hereby granted, free of charge, to any person obtaining  */
/* a copy of this software and associated documentation files (the        */
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/* 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. */
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/**************************************************************************/

#include "networked_multiplayer_enet.h"
#include "core/io/ip.h"
#include "core/io/marshalls.h"
#include "core/os/os.h"

void NetworkedMultiplayerENet::set_transfer_mode(TransferMode p_mode) {
	transfer_mode = p_mode;
}
NetworkedMultiplayerPeer::TransferMode NetworkedMultiplayerENet::get_transfer_mode() const {
	return transfer_mode;
}

void NetworkedMultiplayerENet::set_target_peer(int p_peer) {
	target_peer = p_peer;
}

int NetworkedMultiplayerENet::get_packet_peer() const {
	ERR_FAIL_COND_V_MSG(!active, 1, "The multiplayer instance isn't currently active.");
	ERR_FAIL_COND_V(incoming_packets.size() == 0, 1);

	return incoming_packets.front()->get().from;
}

int NetworkedMultiplayerENet::get_packet_channel() const {
	ERR_FAIL_COND_V_MSG(!active, -1, "The multiplayer instance isn't currently active.");
	ERR_FAIL_COND_V(incoming_packets.size() == 0, -1);

	return incoming_packets.front()->get().channel;
}

int NetworkedMultiplayerENet::get_last_packet_channel() const {
	ERR_FAIL_COND_V_MSG(!active, -1, "The multiplayer instance isn't currently active.");
	ERR_FAIL_COND_V(!current_packet.packet, -1);

	return current_packet.channel;
}

Error NetworkedMultiplayerENet::create_server(int p_port, int p_max_clients, int p_in_bandwidth, int p_out_bandwidth) {
	ERR_FAIL_COND_V_MSG(active, ERR_ALREADY_IN_USE, "The multiplayer instance is already active.");
	ERR_FAIL_COND_V_MSG(p_port < 0 || p_port > 65535, ERR_INVALID_PARAMETER, "The port number must be set between 0 and 65535 (inclusive).");
	ERR_FAIL_COND_V_MSG(p_max_clients < 1 || p_max_clients > 4095, ERR_INVALID_PARAMETER, "The number of clients must be set between 1 and 4095 (inclusive).");
	ERR_FAIL_COND_V_MSG(p_in_bandwidth < 0, ERR_INVALID_PARAMETER, "The incoming bandwidth limit must be greater than or equal to 0 (0 disables the limit).");
	ERR_FAIL_COND_V_MSG(p_out_bandwidth < 0, ERR_INVALID_PARAMETER, "The outgoing bandwidth limit must be greater than or equal to 0 (0 disables the limit).");
	ERR_FAIL_COND_V(dtls_enabled && (dtls_key.is_null() || dtls_cert.is_null()), ERR_INVALID_PARAMETER);

	ENetAddress address;
	memset(&address, 0, sizeof(address));

#ifdef GODOT_ENET
	if (bind_ip.is_wildcard()) {
		address.wildcard = 1;
	} else {
		enet_address_set_ip(&address, bind_ip.get_ipv6(), 16);
	}
#else
	if (bind_ip.is_wildcard()) {
		address.host = 0;
	} else {
		ERR_FAIL_COND_V(!bind_ip.is_ipv4(), ERR_INVALID_PARAMETER);
		address.host = *(uint32_t *)bind_ip.get_ipv4();
	}
#endif
	address.port = p_port;

	host = enet_host_create(&address /* the address to bind the server host to */,
			p_max_clients /* allow up to 32 clients and/or outgoing connections */,
			channel_count /* allow up to channel_count to be used */,
			p_in_bandwidth /* limit incoming bandwidth if > 0 */,
			p_out_bandwidth /* limit outgoing bandwidth if > 0 */);

	ERR_FAIL_COND_V_MSG(!host, ERR_CANT_CREATE, "Couldn't create an ENet multiplayer server.");
#ifdef GODOT_ENET
	if (dtls_enabled) {
		enet_host_dtls_server_setup(host, dtls_key.ptr(), dtls_cert.ptr());
	}
	enet_host_refuse_new_connections(host, refuse_connections);
#endif

	_setup_compressor();
	active = true;
	server = true;
	refuse_connections = false;
	unique_id = 1;
	connection_status = CONNECTION_CONNECTED;
	return OK;
}
Error NetworkedMultiplayerENet::create_client(const String &p_address, int p_port, int p_in_bandwidth, int p_out_bandwidth, int p_client_port) {
	ERR_FAIL_COND_V_MSG(active, ERR_ALREADY_IN_USE, "The multiplayer instance is already active.");
	ERR_FAIL_COND_V_MSG(p_port < 0 || p_port > 65535, ERR_INVALID_PARAMETER, "The server port number must be set between 0 and 65535 (inclusive).");
	ERR_FAIL_COND_V_MSG(p_client_port < 0 || p_client_port > 65535, ERR_INVALID_PARAMETER, "The client port number must be set between 0 and 65535 (inclusive).");
	ERR_FAIL_COND_V_MSG(p_in_bandwidth < 0, ERR_INVALID_PARAMETER, "The incoming bandwidth limit must be greater than or equal to 0 (0 disables the limit).");
	ERR_FAIL_COND_V_MSG(p_out_bandwidth < 0, ERR_INVALID_PARAMETER, "The outgoing bandwidth limit must be greater than or equal to 0 (0 disables the limit).");

	if (p_client_port != 0) {
		ENetAddress c_client;

#ifdef GODOT_ENET
		if (bind_ip.is_wildcard()) {
			c_client.wildcard = 1;
		} else {
			enet_address_set_ip(&c_client, bind_ip.get_ipv6(), 16);
		}
#else
		if (bind_ip.is_wildcard()) {
			c_client.host = 0;
		} else {
			ERR_FAIL_COND_V_MSG(!bind_ip.is_ipv4(), ERR_INVALID_PARAMETER, "Wildcard IP addresses are only permitted in IPv4, not IPv6.");
			c_client.host = *(uint32_t *)bind_ip.get_ipv4();
		}
#endif

		c_client.port = p_client_port;

		host = enet_host_create(&c_client /* create a client host */,
				1 /* only allow 1 outgoing connection */,
				channel_count /* allow up to channel_count to be used */,
				p_in_bandwidth /* limit incoming bandwidth if > 0 */,
				p_out_bandwidth /* limit outgoing bandwidth if > 0 */);
	} else {
		host = enet_host_create(nullptr /* create a client host */,
				1 /* only allow 1 outgoing connection */,
				channel_count /* allow up to channel_count to be used */,
				p_in_bandwidth /* limit incoming bandwidth if > 0 */,
				p_out_bandwidth /* limit outgoing bandwidth if > 0 */);
	}

	ERR_FAIL_COND_V_MSG(!host, ERR_CANT_CREATE, "Couldn't create the ENet client host.");
#ifdef GODOT_ENET
	if (dtls_enabled) {
		enet_host_dtls_client_setup(host, dtls_cert.ptr(), dtls_verify, dtls_hostname.empty() ? p_address.utf8().get_data() : dtls_hostname.utf8().get_data());
	}
	enet_host_refuse_new_connections(host, refuse_connections);
#endif

	_setup_compressor();

	IP_Address ip;
	if (p_address.is_valid_ip_address()) {
		ip = p_address;
	} else {
#ifdef GODOT_ENET
		ip = IP::get_singleton()->resolve_hostname(p_address);
#else
		ip = IP::get_singleton()->resolve_hostname(p_address, IP::TYPE_IPV4);
#endif

		if (!ip.is_valid()) {
			enet_host_destroy(host);
			ERR_FAIL_V_MSG(ERR_CANT_RESOLVE, "Couldn't resolve the server IP address or domain name.");
		}
	}

	ENetAddress address;
#ifdef GODOT_ENET
	enet_address_set_ip(&address, ip.get_ipv6(), 16);
#else
	if (!ip.is_ipv4()) {
		enet_host_destroy(host);
		ERR_FAIL_V_MSG(ERR_INVALID_PARAMETER, "Connecting to an IPv6 server isn't supported when using vanilla ENet. Recompile Godot with the bundled ENet library.");
	}
	address.host = *(uint32_t *)ip.get_ipv4();
#endif
	address.port = p_port;

	unique_id = _gen_unique_id();

	// Initiate connection, allocating enough channels
	ENetPeer *peer = enet_host_connect(host, &address, channel_count, unique_id);

	if (peer == nullptr) {
		enet_host_destroy(host);
		ERR_FAIL_V_MSG(ERR_CANT_CREATE, "Couldn't connect to the ENet multiplayer server.");
	}

	// Technically safe to ignore the peer or anything else.

	connection_status = CONNECTION_CONNECTING;
	active = true;
	server = false;
	refuse_connections = false;

	return OK;
}

void NetworkedMultiplayerENet::poll() {
	ERR_FAIL_COND_MSG(!active, "The multiplayer instance isn't currently active.");

	_pop_current_packet();

	if (!host || !active) { // Might be disconnected
		return;
	}

	ENetEvent event;
	int ret = enet_host_service(host, &event, 0);

	if (ret < 0) {
		ERR_FAIL_MSG("Enet host service error");
	} else if (ret == 0) {
		return; // No events
	}

	/* Keep servicing until there are no available events left in the queue. */
	do {
		if (!host || !active) { // Check again after every event
			return;
		}

		switch (event.type) {
			case ENET_EVENT_TYPE_CONNECT: {
				// Store any relevant client information here.

				if (server && refuse_connections) {
					enet_peer_reset(event.peer);
					break;
				}

				// A client joined with an invalid ID (negative values, 0, and 1 are reserved).
				// Probably trying to exploit us.
				if (server && ((int)event.data < 2 || peer_map.has((int)event.data))) {
					enet_peer_reset(event.peer);
					ERR_CONTINUE(true);
				}

				int *new_id = memnew(int);
				*new_id = event.data;

				if (*new_id == 0) { // Data zero is sent by server (enet won't let you configure this). Server is always 1.
					*new_id = 1;
				}

				event.peer->data = new_id;

				peer_map[*new_id] = event.peer;

				connection_status = CONNECTION_CONNECTED; // If connecting, this means it connected to something!

				emit_signal("peer_connected", *new_id);

				if (server) {
					// Do not notify other peers when server_relay is disabled.
					if (!server_relay) {
						break;
					}

					// Someone connected, notify all the peers available
					for (Map<int, ENetPeer *>::Element *E = peer_map.front(); E; E = E->next()) {
						if (E->key() == *new_id) {
							continue;
						}
						// Send existing peers to new peer
						ENetPacket *packet = enet_packet_create(nullptr, 8, ENET_PACKET_FLAG_RELIABLE);
						encode_uint32(SYSMSG_ADD_PEER, &packet->data[0]);
						encode_uint32(E->key(), &packet->data[4]);
						enet_peer_send(event.peer, SYSCH_CONFIG, packet);
						// Send the new peer to existing peers
						packet = enet_packet_create(nullptr, 8, ENET_PACKET_FLAG_RELIABLE);
						encode_uint32(SYSMSG_ADD_PEER, &packet->data[0]);
						encode_uint32(*new_id, &packet->data[4]);
						enet_peer_send(E->get(), SYSCH_CONFIG, packet);
					}
				} else {
					emit_signal("connection_succeeded");
				}

			} break;
			case ENET_EVENT_TYPE_DISCONNECT: {
				// Reset the peer's client information.

				int *id = (int *)event.peer->data;

				if (!id) {
					if (!server) {
						emit_signal("connection_failed");
					}
					// Never fully connected.
					break;
				}

				if (!server) {
					// Client just disconnected from server.
					emit_signal("server_disconnected");
					close_connection();
					return;
				} else if (server_relay) {
					// Server just received a client disconnect and is in relay mode, notify everyone else.
					for (Map<int, ENetPeer *>::Element *E = peer_map.front(); E; E = E->next()) {
						if (E->key() == *id) {
							continue;
						}

						ENetPacket *packet = enet_packet_create(nullptr, 8, ENET_PACKET_FLAG_RELIABLE);
						encode_uint32(SYSMSG_REMOVE_PEER, &packet->data[0]);
						encode_uint32(*id, &packet->data[4]);
						enet_peer_send(E->get(), SYSCH_CONFIG, packet);
					}
				}

				emit_signal("peer_disconnected", *id);
				peer_map.erase(*id);
				memdelete(id);
			} break;
			case ENET_EVENT_TYPE_RECEIVE: {
				if (event.channelID == SYSCH_CONFIG) {
					// Some config message
					ERR_CONTINUE(event.packet->dataLength < 8);

					// Only server can send config messages
					ERR_CONTINUE(server);

					int msg = decode_uint32(&event.packet->data[0]);
					int id = decode_uint32(&event.packet->data[4]);

					switch (msg) {
						case SYSMSG_ADD_PEER: {
							peer_map[id] = NULL;
							emit_signal("peer_connected", id);

						} break;
						case SYSMSG_REMOVE_PEER: {
							peer_map.erase(id);
							emit_signal("peer_disconnected", id);
						} break;
					}

					enet_packet_destroy(event.packet);
				} else if (event.channelID < channel_count) {
					Packet packet;
					packet.packet = event.packet;

					uint32_t *id = (uint32_t *)event.peer->data;

					ERR_CONTINUE(event.packet->dataLength < 8);

					uint32_t source = decode_uint32(&event.packet->data[0]);
					int target = decode_uint32(&event.packet->data[4]);

					packet.from = source;
					packet.channel = event.channelID;

					if (server) {
						// Someone is cheating and trying to fake the source!
						ERR_CONTINUE(source != *id);

						packet.from = *id;

						if (target == 1) {
							// To myself and only myself
							incoming_packets.push_back(packet);
						} else if (!server_relay) {
							// When relaying is disabled, other destinations will only be processed by the server.
							if (target == 0 || target < -1) {
								incoming_packets.push_back(packet);
							}
							continue;
						} else if (target == 0) {
							// Re-send to everyone but sender :|

							incoming_packets.push_back(packet);
							// And make copies for sending
							for (Map<int, ENetPeer *>::Element *E = peer_map.front(); E; E = E->next()) {
								if (uint32_t(E->key()) == source) { // Do not resend to self
									continue;
								}

								ENetPacket *packet2 = enet_packet_create(packet.packet->data, packet.packet->dataLength, packet.packet->flags);

								enet_peer_send(E->get(), event.channelID, packet2);
							}

						} else if (target < 0) {
							// To all but one

							// And make copies for sending
							for (Map<int, ENetPeer *>::Element *E = peer_map.front(); E; E = E->next()) {
								if (uint32_t(E->key()) == source || E->key() == -target) { // Do not resend to self, also do not send to excluded
									continue;
								}

								ENetPacket *packet2 = enet_packet_create(packet.packet->data, packet.packet->dataLength, packet.packet->flags);

								enet_peer_send(E->get(), event.channelID, packet2);
							}

							if (-target != 1) {
								// Server is not excluded
								incoming_packets.push_back(packet);
							} else {
								// Server is excluded, erase packet
								enet_packet_destroy(packet.packet);
							}

						} else {
							// To someone else, specifically
							ERR_CONTINUE(!peer_map.has(target));
							enet_peer_send(peer_map[target], event.channelID, packet.packet);
						}
					} else {
						incoming_packets.push_back(packet);
					}

					// Destroy packet later
				} else {
					ERR_CONTINUE(true);
				}

			} break;
			case ENET_EVENT_TYPE_NONE: {
				// Do nothing
			} break;
		}
	} while (enet_host_check_events(host, &event) > 0);
}

bool NetworkedMultiplayerENet::is_server() const {
	ERR_FAIL_COND_V_MSG(!active, false, "The multiplayer instance isn't currently active.");

	return server;
}

void NetworkedMultiplayerENet::close_connection(uint32_t wait_usec) {
	if (!active) {
		return;
	}

	_pop_current_packet();

	bool peers_disconnected = false;
	for (Map<int, ENetPeer *>::Element *E = peer_map.front(); E; E = E->next()) {
		if (E->get()) {
			enet_peer_disconnect_now(E->get(), unique_id);
			int *id = (int *)(E->get()->data);
			memdelete(id);
			peers_disconnected = true;
		}
	}

	if (peers_disconnected) {
		enet_host_flush(host);

		if (wait_usec > 0) {
			OS::get_singleton()->delay_usec(wait_usec); // Wait for disconnection packets to send
		}
	}

	enet_host_destroy(host);
	active = false;
	incoming_packets.clear();
	peer_map.clear();
	unique_id = 1; // Server is 1
	connection_status = CONNECTION_DISCONNECTED;
}

void NetworkedMultiplayerENet::disconnect_peer(int p_peer, bool now) {
	ERR_FAIL_COND_MSG(!active, "The multiplayer instance isn't currently active.");
	ERR_FAIL_COND_MSG(!is_server(), "Can't disconnect a peer when not acting as a server.");
	ERR_FAIL_COND_MSG(!peer_map.has(p_peer), vformat("Peer ID %d not found in the list of peers.", p_peer));

	if (now) {
		int *id = (int *)peer_map[p_peer]->data;
		enet_peer_disconnect_now(peer_map[p_peer], 0);

		// enet_peer_disconnect_now doesn't generate ENET_EVENT_TYPE_DISCONNECT,
		// notify everyone else, send disconnect signal & remove from peer_map like in poll()
		if (server_relay) {
			for (Map<int, ENetPeer *>::Element *E = peer_map.front(); E; E = E->next()) {
				if (E->key() == p_peer) {
					continue;
				}

				ENetPacket *packet = enet_packet_create(nullptr, 8, ENET_PACKET_FLAG_RELIABLE);
				encode_uint32(SYSMSG_REMOVE_PEER, &packet->data[0]);
				encode_uint32(p_peer, &packet->data[4]);
				enet_peer_send(E->get(), SYSCH_CONFIG, packet);
			}
		}

		if (id) {
			memdelete(id);
		}

		emit_signal("peer_disconnected", p_peer);
		peer_map.erase(p_peer);
	} else {
		enet_peer_disconnect_later(peer_map[p_peer], 0);
	}
}

int NetworkedMultiplayerENet::get_available_packet_count() const {
	return incoming_packets.size();
}

Error NetworkedMultiplayerENet::get_packet(const uint8_t **r_buffer, int &r_buffer_size) {
	ERR_FAIL_COND_V_MSG(incoming_packets.size() == 0, ERR_UNAVAILABLE, "No incoming packets available.");

	_pop_current_packet();

	current_packet = incoming_packets.front()->get();
	incoming_packets.pop_front();

	*r_buffer = (const uint8_t *)(&current_packet.packet->data[8]);
	r_buffer_size = current_packet.packet->dataLength - 8;

	return OK;
}

Error NetworkedMultiplayerENet::put_packet(const uint8_t *p_buffer, int p_buffer_size) {
	ERR_FAIL_COND_V_MSG(!active, ERR_UNCONFIGURED, "The multiplayer instance isn't currently active.");
	ERR_FAIL_COND_V_MSG(connection_status != CONNECTION_CONNECTED, ERR_UNCONFIGURED, "The multiplayer instance isn't currently connected to any server or client.");

	int packet_flags = 0;
	int channel = SYSCH_RELIABLE;

	switch (transfer_mode) {
		case TRANSFER_MODE_UNRELIABLE: {
			if (always_ordered) {
				packet_flags = 0;
			} else {
				packet_flags = ENET_PACKET_FLAG_UNSEQUENCED;
			}
			channel = SYSCH_UNRELIABLE;
			packet_flags |= ENET_PACKET_FLAG_UNRELIABLE_FRAGMENT;
		} break;
		case TRANSFER_MODE_UNRELIABLE_ORDERED: {
			packet_flags = ENET_PACKET_FLAG_UNRELIABLE_FRAGMENT;
			channel = SYSCH_UNRELIABLE;
		} break;
		case TRANSFER_MODE_RELIABLE: {
			packet_flags = ENET_PACKET_FLAG_RELIABLE;
			channel = SYSCH_RELIABLE;
		} break;
	}

	if (transfer_channel > SYSCH_CONFIG) {
		channel = transfer_channel;
	}

#ifdef DEBUG_ENABLED
	if ((packet_flags & ENET_PACKET_FLAG_UNRELIABLE_FRAGMENT) && p_buffer_size + 8 > ENET_HOST_DEFAULT_MTU) {
		WARN_PRINT_ONCE(vformat("Sending %d bytes unrealiably which is above the MTU (%d), this will result in higher packet loss", p_buffer_size + 8, host->mtu));
	}
#endif

	Map<int, ENetPeer *>::Element *E = nullptr;

	if (target_peer != 0) {
		E = peer_map.find(ABS(target_peer));
		ERR_FAIL_COND_V_MSG(!E, ERR_INVALID_PARAMETER, vformat("Invalid target peer: %d", target_peer));
	}

	ENetPacket *packet = enet_packet_create(nullptr, p_buffer_size + 8, packet_flags);
	encode_uint32(unique_id, &packet->data[0]); // Source ID
	encode_uint32(target_peer, &packet->data[4]); // Dest ID
	memcpy(&packet->data[8], p_buffer, p_buffer_size);

	if (server) {
		if (target_peer == 0) {
			enet_host_broadcast(host, channel, packet);
		} else if (target_peer < 0) {
			// Send to all but one
			// and make copies for sending

			int exclude = -target_peer;

			for (Map<int, ENetPeer *>::Element *F = peer_map.front(); F; F = F->next()) {
				if (F->key() == exclude) { // Exclude packet
					continue;
				}

				ENetPacket *packet2 = enet_packet_create(packet->data, packet->dataLength, packet_flags);

				enet_peer_send(F->get(), channel, packet2);
			}

			enet_packet_destroy(packet); // Original packet no longer needed
		} else {
			enet_peer_send(E->get(), channel, packet);
		}
	} else {
		ERR_FAIL_COND_V(!peer_map.has(1), ERR_BUG);
		enet_peer_send(peer_map[1], channel, packet); // Send to server for broadcast
	}

	enet_host_flush(host);

	return OK;
}

int NetworkedMultiplayerENet::get_max_packet_size() const {
	return 1 << 24; // Anything is good
}

void NetworkedMultiplayerENet::_pop_current_packet() {
	if (current_packet.packet) {
		enet_packet_destroy(current_packet.packet);
		current_packet.packet = nullptr;
		current_packet.from = 0;
		current_packet.channel = -1;
	}
}

NetworkedMultiplayerPeer::ConnectionStatus NetworkedMultiplayerENet::get_connection_status() const {
	return connection_status;
}

uint32_t NetworkedMultiplayerENet::_gen_unique_id() const {
	uint32_t hash = 0;

	while (hash == 0 || hash == 1) {
		hash = hash_djb2_one_32(
				(uint32_t)OS::get_singleton()->get_ticks_usec());
		hash = hash_djb2_one_32(
				(uint32_t)OS::get_singleton()->get_unix_time(), hash);
		hash = hash_djb2_one_32(
				(uint32_t)OS::get_singleton()->get_user_data_dir().hash64(), hash);
		hash = hash_djb2_one_32(
				(uint32_t)((uint64_t)this), hash); // Rely on ASLR heap
		hash = hash_djb2_one_32(
				(uint32_t)((uint64_t)&hash), hash); // Rely on ASLR stack

		hash = hash & 0x7FFFFFFF; // Make it compatible with unsigned, since negative ID is used for exclusion
	}

	return hash;
}

int NetworkedMultiplayerENet::get_unique_id() const {
	ERR_FAIL_COND_V_MSG(!active, 0, "The multiplayer instance isn't currently active.");
	return unique_id;
}

void NetworkedMultiplayerENet::set_refuse_new_connections(bool p_enable) {
	refuse_connections = p_enable;
#ifdef GODOT_ENET
	if (active) {
		enet_host_refuse_new_connections(host, p_enable);
	}
#endif
}

bool NetworkedMultiplayerENet::is_refusing_new_connections() const {
	return refuse_connections;
}

void NetworkedMultiplayerENet::set_compression_mode(CompressionMode p_mode) {
	compression_mode = p_mode;
}

NetworkedMultiplayerENet::CompressionMode NetworkedMultiplayerENet::get_compression_mode() const {
	return compression_mode;
}

size_t NetworkedMultiplayerENet::enet_compress(void *context, const ENetBuffer *inBuffers, size_t inBufferCount, size_t inLimit, enet_uint8 *outData, size_t outLimit) {
	NetworkedMultiplayerENet *enet = (NetworkedMultiplayerENet *)(context);
<--- C-style pointer casting [+]
C-style pointer casting detected. C++ offers four different kinds of casts as replacements: static_cast, const_cast, dynamic_cast and reinterpret_cast. A C-style cast could evaluate to any of those automatically, thus it is considered safer if the programmer explicitly states which kind of cast is expected. See also: https://www.securecoding.cert.org/confluence/display/cplusplus/EXP05-CPP.+Do+not+use+C-style+casts.

	if (size_t(enet->src_compressor_mem.size()) < inLimit) {
		enet->src_compressor_mem.resize(inLimit);
	}

	int total = inLimit;
	int ofs = 0;
	while (total) {
		for (size_t i = 0; i < inBufferCount; i++) {
			int to_copy = MIN(total, int(inBuffers[i].dataLength));
			memcpy(&enet->src_compressor_mem.write[ofs], inBuffers[i].data, to_copy);
			ofs += to_copy;
			total -= to_copy;
		}
	}

	Compression::Mode mode;

	switch (enet->compression_mode) {
		case COMPRESS_FASTLZ: {
			mode = Compression::MODE_FASTLZ;
		} break;
		case COMPRESS_ZLIB: {
			mode = Compression::MODE_DEFLATE;
		} break;
		case COMPRESS_ZSTD: {
			mode = Compression::MODE_ZSTD;
		} break;
		default: {
			ERR_FAIL_V_MSG(0, vformat("Invalid ENet compression mode: %d", enet->compression_mode));
		}
	}

	int req_size = Compression::get_max_compressed_buffer_size(ofs, mode);
	if (enet->dst_compressor_mem.size() < req_size) {
		enet->dst_compressor_mem.resize(req_size);
	}
	int ret = Compression::compress(enet->dst_compressor_mem.ptrw(), enet->src_compressor_mem.ptr(), ofs, mode);

	if (ret < 0) {
		return 0;
	}

	if (ret > int(outLimit)) {
		return 0; // Do not bother
	}

	memcpy(outData, enet->dst_compressor_mem.ptr(), ret);

	return ret;
}

size_t NetworkedMultiplayerENet::enet_decompress(void *context, const enet_uint8 *inData, size_t inLimit, enet_uint8 *outData, size_t outLimit) {
	NetworkedMultiplayerENet *enet = (NetworkedMultiplayerENet *)(context);
<--- C-style pointer casting [+]
C-style pointer casting detected. C++ offers four different kinds of casts as replacements: static_cast, const_cast, dynamic_cast and reinterpret_cast. A C-style cast could evaluate to any of those automatically, thus it is considered safer if the programmer explicitly states which kind of cast is expected. See also: https://www.securecoding.cert.org/confluence/display/cplusplus/EXP05-CPP.+Do+not+use+C-style+casts.
	int ret = -1;
	switch (enet->compression_mode) {
		case COMPRESS_FASTLZ: {
			ret = Compression::decompress(outData, outLimit, inData, inLimit, Compression::MODE_FASTLZ);
		} break;
		case COMPRESS_ZLIB: {
			ret = Compression::decompress(outData, outLimit, inData, inLimit, Compression::MODE_DEFLATE);
		} break;
		case COMPRESS_ZSTD: {
			ret = Compression::decompress(outData, outLimit, inData, inLimit, Compression::MODE_ZSTD);
		} break;
		default: {
		}
	}
	if (ret < 0) {
		return 0;
	} else {
		return ret;
	}
}

void NetworkedMultiplayerENet::_setup_compressor() {
	switch (compression_mode) {
		case COMPRESS_NONE: {
			enet_host_compress(host, nullptr);
		} break;
		case COMPRESS_RANGE_CODER: {
			enet_host_compress_with_range_coder(host);
		} break;
		case COMPRESS_FASTLZ:
		case COMPRESS_ZLIB:
		case COMPRESS_ZSTD: {
			enet_host_compress(host, &enet_compressor);
		} break;
	}
}

void NetworkedMultiplayerENet::enet_compressor_destroy(void *context) {
	// Nothing to do
}

IP_Address NetworkedMultiplayerENet::get_peer_address(int p_peer_id) const {
	ERR_FAIL_COND_V_MSG(!peer_map.has(p_peer_id), IP_Address(), vformat("Peer ID %d not found in the list of peers.", p_peer_id));
	ERR_FAIL_COND_V_MSG(!is_server() && p_peer_id != 1, IP_Address(), "Can't get the address of peers other than the server (ID -1) when acting as a client.");
	ERR_FAIL_COND_V_MSG(peer_map[p_peer_id] == NULL, IP_Address(), vformat("Peer ID %d found in the list of peers, but is null.", p_peer_id));

	IP_Address out;
#ifdef GODOT_ENET
	out.set_ipv6((uint8_t *)&(peer_map[p_peer_id]->address.host));
#else
	out.set_ipv4((uint8_t *)&(peer_map[p_peer_id]->address.host));
#endif

	return out;
}

int NetworkedMultiplayerENet::get_peer_port(int p_peer_id) const {
	ERR_FAIL_COND_V_MSG(!peer_map.has(p_peer_id), 0, vformat("Peer ID %d not found in the list of peers.", p_peer_id));
	ERR_FAIL_COND_V_MSG(!is_server() && p_peer_id != 1, 0, "Can't get the address of peers other than the server (ID -1) when acting as a client.");
	ERR_FAIL_COND_V_MSG(peer_map[p_peer_id] == NULL, 0, vformat("Peer ID %d found in the list of peers, but is null.", p_peer_id));
#ifdef GODOT_ENET
	return peer_map[p_peer_id]->address.port;
#else
	return peer_map[p_peer_id]->address.port;
#endif
}

void NetworkedMultiplayerENet::set_peer_timeout(int p_peer_id, int p_timeout_limit, int p_timeout_min, int p_timeout_max) {
	ERR_FAIL_COND_MSG(!peer_map.has(p_peer_id), vformat("Peer ID %d not found in the list of peers.", p_peer_id));
	ERR_FAIL_COND_MSG(!is_server() && p_peer_id != 1, "Can't change the timeout of peers other then the server when acting as a client.");
	ERR_FAIL_COND_MSG(peer_map[p_peer_id] == nullptr, vformat("Peer ID %d found in the list of peers, but is null.", p_peer_id));
	ERR_FAIL_COND_MSG(p_timeout_limit > p_timeout_min || p_timeout_min > p_timeout_max, "Timeout limit must be less than minimum timeout, which itself must be less then maximum timeout");
	enet_peer_timeout(peer_map[p_peer_id], p_timeout_limit, p_timeout_min, p_timeout_max);
}

void NetworkedMultiplayerENet::set_transfer_channel(int p_channel) {
	ERR_FAIL_COND_MSG(p_channel < -1 || p_channel >= channel_count, vformat("The transfer channel must be set between 0 and %d, inclusive (got %d).", channel_count - 1, p_channel));
	ERR_FAIL_COND_MSG(p_channel == SYSCH_CONFIG, vformat("The channel %d is reserved.", SYSCH_CONFIG));
	transfer_channel = p_channel;
}

int NetworkedMultiplayerENet::get_transfer_channel() const {
	return transfer_channel;
}

void NetworkedMultiplayerENet::set_channel_count(int p_channel) {
	ERR_FAIL_COND_MSG(active, "The channel count can't be set while the multiplayer instance is active.");
	ERR_FAIL_COND_MSG(p_channel < SYSCH_MAX, vformat("The channel count must be greater than or equal to %d to account for reserved channels (got %d).", SYSCH_MAX, p_channel));
	channel_count = p_channel;
}

int NetworkedMultiplayerENet::get_channel_count() const {
	return channel_count;
}

void NetworkedMultiplayerENet::set_always_ordered(bool p_ordered) {
	always_ordered = p_ordered;
}

bool NetworkedMultiplayerENet::is_always_ordered() const {
	return always_ordered;
}

void NetworkedMultiplayerENet::set_server_relay_enabled(bool p_enabled) {
	ERR_FAIL_COND_MSG(active, "Server relaying can't be toggled while the multiplayer instance is active.");

	server_relay = p_enabled;
}

bool NetworkedMultiplayerENet::is_server_relay_enabled() const {
	return server_relay;
}

void NetworkedMultiplayerENet::_bind_methods() {
	ClassDB::bind_method(D_METHOD("create_server", "port", "max_clients", "in_bandwidth", "out_bandwidth"), &NetworkedMultiplayerENet::create_server, DEFVAL(32), DEFVAL(0), DEFVAL(0));
	ClassDB::bind_method(D_METHOD("create_client", "address", "port", "in_bandwidth", "out_bandwidth", "client_port"), &NetworkedMultiplayerENet::create_client, DEFVAL(0), DEFVAL(0), DEFVAL(0));
	ClassDB::bind_method(D_METHOD("close_connection", "wait_usec"), &NetworkedMultiplayerENet::close_connection, DEFVAL(100));
	ClassDB::bind_method(D_METHOD("disconnect_peer", "id", "now"), &NetworkedMultiplayerENet::disconnect_peer, DEFVAL(false));
	ClassDB::bind_method(D_METHOD("set_compression_mode", "mode"), &NetworkedMultiplayerENet::set_compression_mode);
	ClassDB::bind_method(D_METHOD("get_compression_mode"), &NetworkedMultiplayerENet::get_compression_mode);
	ClassDB::bind_method(D_METHOD("set_bind_ip", "ip"), &NetworkedMultiplayerENet::set_bind_ip);
	ClassDB::bind_method(D_METHOD("set_dtls_enabled", "enabled"), &NetworkedMultiplayerENet::set_dtls_enabled);
	ClassDB::bind_method(D_METHOD("is_dtls_enabled"), &NetworkedMultiplayerENet::is_dtls_enabled);
	ClassDB::bind_method(D_METHOD("set_dtls_key", "key"), &NetworkedMultiplayerENet::set_dtls_key);
	ClassDB::bind_method(D_METHOD("set_dtls_certificate", "certificate"), &NetworkedMultiplayerENet::set_dtls_certificate);
	ClassDB::bind_method(D_METHOD("set_dtls_verify_enabled", "enabled"), &NetworkedMultiplayerENet::set_dtls_verify_enabled);
	ClassDB::bind_method(D_METHOD("is_dtls_verify_enabled"), &NetworkedMultiplayerENet::is_dtls_verify_enabled);
	ClassDB::bind_method(D_METHOD("set_dtls_hostname", "hostname"), &NetworkedMultiplayerENet::set_dtls_hostname);
	ClassDB::bind_method(D_METHOD("get_dtls_hostname"), &NetworkedMultiplayerENet::get_dtls_hostname);
	ClassDB::bind_method(D_METHOD("get_peer_address", "id"), &NetworkedMultiplayerENet::get_peer_address);
	ClassDB::bind_method(D_METHOD("get_peer_port", "id"), &NetworkedMultiplayerENet::get_peer_port);
	ClassDB::bind_method(D_METHOD("set_peer_timeout", "id", "timeout_limit", "timeout_min", "timeout_max"), &NetworkedMultiplayerENet::set_peer_timeout);

	ClassDB::bind_method(D_METHOD("get_packet_channel"), &NetworkedMultiplayerENet::get_packet_channel);
	ClassDB::bind_method(D_METHOD("get_last_packet_channel"), &NetworkedMultiplayerENet::get_last_packet_channel);
	ClassDB::bind_method(D_METHOD("set_transfer_channel", "channel"), &NetworkedMultiplayerENet::set_transfer_channel);
	ClassDB::bind_method(D_METHOD("get_transfer_channel"), &NetworkedMultiplayerENet::get_transfer_channel);
	ClassDB::bind_method(D_METHOD("set_channel_count", "channels"), &NetworkedMultiplayerENet::set_channel_count);
	ClassDB::bind_method(D_METHOD("get_channel_count"), &NetworkedMultiplayerENet::get_channel_count);
	ClassDB::bind_method(D_METHOD("set_always_ordered", "ordered"), &NetworkedMultiplayerENet::set_always_ordered);
	ClassDB::bind_method(D_METHOD("is_always_ordered"), &NetworkedMultiplayerENet::is_always_ordered);
	ClassDB::bind_method(D_METHOD("set_server_relay_enabled", "enabled"), &NetworkedMultiplayerENet::set_server_relay_enabled);
	ClassDB::bind_method(D_METHOD("is_server_relay_enabled"), &NetworkedMultiplayerENet::is_server_relay_enabled);

	ADD_PROPERTY(PropertyInfo(Variant::INT, "compression_mode", PROPERTY_HINT_ENUM, "None,Range Coder,FastLZ,ZLib,ZStd"), "set_compression_mode", "get_compression_mode");
	ADD_PROPERTY(PropertyInfo(Variant::INT, "transfer_channel"), "set_transfer_channel", "get_transfer_channel");
	ADD_PROPERTY(PropertyInfo(Variant::INT, "channel_count"), "set_channel_count", "get_channel_count");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "always_ordered"), "set_always_ordered", "is_always_ordered");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "server_relay"), "set_server_relay_enabled", "is_server_relay_enabled");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "dtls_verify"), "set_dtls_verify_enabled", "is_dtls_verify_enabled");
	ADD_PROPERTY(PropertyInfo(Variant::STRING, "dtls_hostname"), "set_dtls_hostname", "get_dtls_hostname");
	ADD_PROPERTY(PropertyInfo(Variant::BOOL, "use_dtls"), "set_dtls_enabled", "is_dtls_enabled");

	BIND_ENUM_CONSTANT(COMPRESS_NONE);
	BIND_ENUM_CONSTANT(COMPRESS_RANGE_CODER);
	BIND_ENUM_CONSTANT(COMPRESS_FASTLZ);
	BIND_ENUM_CONSTANT(COMPRESS_ZLIB);
	BIND_ENUM_CONSTANT(COMPRESS_ZSTD);
}

NetworkedMultiplayerENet::NetworkedMultiplayerENet() {<--- Member variable 'NetworkedMultiplayerENet::peer' is not initialized in the constructor.<--- Member variable 'NetworkedMultiplayerENet::host' is not initialized in the constructor.
	active = false;
	server = false;
	refuse_connections = false;
	server_relay = true;
	unique_id = 0;
	target_peer = 0;
	current_packet.packet = nullptr;
	transfer_mode = TRANSFER_MODE_RELIABLE;
<--- Variable 'transfer_mode' is assigned in constructor body. Consider performing initialization in initialization list. [+]
When an object of a class is created, the constructors of all member variables are called consecutively in the order the variables are declared, even if you don't explicitly write them to the initialization list. You could avoid assigning 'transfer_mode' a value by passing the value to the constructor in the initialization list.
	channel_count = SYSCH_MAX;
	transfer_channel = -1;
	always_ordered = false;
	connection_status = CONNECTION_DISCONNECTED;
<--- Variable 'connection_status' is assigned in constructor body. Consider performing initialization in initialization list. [+]
When an object of a class is created, the constructors of all member variables are called consecutively in the order the variables are declared, even if you don't explicitly write them to the initialization list. You could avoid assigning 'connection_status' a value by passing the value to the constructor in the initialization list.
	compression_mode = COMPRESS_RANGE_CODER;
	enet_compressor.context = this;
	enet_compressor.compress = enet_compress;
	enet_compressor.decompress = enet_decompress;
	enet_compressor.destroy = enet_compressor_destroy;

	bind_ip = IP_Address("*");
<--- Variable 'bind_ip' is assigned in constructor body. Consider performing initialization in initialization list. [+]
When an object of a class is created, the constructors of all member variables are called consecutively in the order the variables are declared, even if you don't explicitly write them to the initialization list. You could avoid assigning 'bind_ip' a value by passing the value to the constructor in the initialization list.

	dtls_enabled = false;
	dtls_verify = true;
}

NetworkedMultiplayerENet::~NetworkedMultiplayerENet() {
	if (active) {
		close_connection();
	}
}

// Sets IP for ENet to bind when using create_server or create_client
// if no IP is set, then ENet bind to ENET_HOST_ANY
void NetworkedMultiplayerENet::set_bind_ip(const IP_Address &p_ip) {
	ERR_FAIL_COND_MSG(!p_ip.is_valid() && !p_ip.is_wildcard(), vformat("Invalid bind IP address: %s", String(p_ip)));

	bind_ip = p_ip;
}

void NetworkedMultiplayerENet::set_dtls_enabled(bool p_enabled) {
	ERR_FAIL_COND(active);
	dtls_enabled = p_enabled;
}

bool NetworkedMultiplayerENet::is_dtls_enabled() const {
	return dtls_enabled;
}

void NetworkedMultiplayerENet::set_dtls_verify_enabled(bool p_enabled) {
	ERR_FAIL_COND(active);
	dtls_verify = p_enabled;
}

bool NetworkedMultiplayerENet::is_dtls_verify_enabled() const {
	return dtls_verify;
}

void NetworkedMultiplayerENet::set_dtls_key(Ref<CryptoKey> p_key) {
	ERR_FAIL_COND(active);
	dtls_key = p_key;
}

void NetworkedMultiplayerENet::set_dtls_certificate(Ref<X509Certificate> p_cert) {
	ERR_FAIL_COND(active);
	dtls_cert = p_cert;
}

void NetworkedMultiplayerENet::set_dtls_hostname(const String &p_hostname) {
	ERR_FAIL_COND(active);
	dtls_hostname = p_hostname;
}

String NetworkedMultiplayerENet::get_dtls_hostname() const {
	return dtls_hostname;
}