godot/core/io/udp_server.cpp
Fabio Alessandrelli 468a1c0271 UDPServer handles PacketPeerUDP-client association
UDPServer now uses a single socket which is shared with the
PacketPeerUDP it creates and has a new `poll` function to read incoming
packets on that socket and delivers them to the appropriate peer.
PacketPeerUDP created this way never reads from the socket, but are
allowed to write on it using sendto.

This is needed because Windows (unlike Linux/BSD) does not support
packet routing when multiple sockets are bound on the same address/port.

(cherry picked from commit 147bbe2155)
2020-07-15 12:48:18 +02:00

206 lines
6.4 KiB
C++

/*************************************************************************/
/* udp_server.cpp */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2020 Juan Linietsky, Ariel Manzur. */
/* Copyright (c) 2014-2020 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 "udp_server.h"
void UDPServer::_bind_methods() {
ClassDB::bind_method(D_METHOD("listen", "port", "bind_address"), &UDPServer::listen, DEFVAL("*"));
ClassDB::bind_method(D_METHOD("poll"), &UDPServer::poll);
ClassDB::bind_method(D_METHOD("is_connection_available"), &UDPServer::is_connection_available);
ClassDB::bind_method(D_METHOD("is_listening"), &UDPServer::is_listening);
ClassDB::bind_method(D_METHOD("take_connection"), &UDPServer::take_connection);
ClassDB::bind_method(D_METHOD("stop"), &UDPServer::stop);
ClassDB::bind_method(D_METHOD("set_max_pending_connections", "max_pending_connections"), &UDPServer::set_max_pending_connections);
ClassDB::bind_method(D_METHOD("get_max_pending_connections"), &UDPServer::get_max_pending_connections);
ADD_PROPERTY(PropertyInfo(Variant::INT, "max_pending_connections", PROPERTY_HINT_RANGE, "0,256,1"), "set_max_pending_connections", "get_max_pending_connections");
}
Error UDPServer::poll() {
ERR_FAIL_COND_V(!_sock.is_valid(), ERR_UNAVAILABLE);
if (!_sock->is_open()) {
return ERR_UNCONFIGURED;
}
Error err;
int read;
IP_Address ip;
uint16_t port;
while (true) {
err = _sock->recvfrom(recv_buffer, sizeof(recv_buffer), read, ip, port);
if (err != OK) {
if (err == ERR_BUSY) {
break;
}
return FAILED;
}
Peer p;
p.ip = ip;
p.port = port;
List<Peer>::Element *E = peers.find(p);
if (!E) {
E = pending.find(p);
}
if (E) {
E->get().peer->store_packet(ip, port, recv_buffer, read);
} else {
if (pending.size() >= max_pending_connections) {
// Drop connection.
continue;
}
// It's a new peer, add it to the pending list.
Peer peer;
peer.ip = ip;
peer.port = port;
peer.peer = memnew(PacketPeerUDP);
peer.peer->connect_shared_socket(_sock, ip, port, this);
peer.peer->store_packet(ip, port, recv_buffer, read);
pending.push_back(peer);
}
}
return OK;
}
Error UDPServer::listen(uint16_t p_port, const IP_Address &p_bind_address) {
ERR_FAIL_COND_V(!_sock.is_valid(), ERR_UNAVAILABLE);
ERR_FAIL_COND_V(_sock->is_open(), ERR_ALREADY_IN_USE);
ERR_FAIL_COND_V(!p_bind_address.is_valid() && !p_bind_address.is_wildcard(), ERR_INVALID_PARAMETER);
Error err;
IP::Type ip_type = IP::TYPE_ANY;
if (p_bind_address.is_valid())
ip_type = p_bind_address.is_ipv4() ? IP::TYPE_IPV4 : IP::TYPE_IPV6;
err = _sock->open(NetSocket::TYPE_UDP, ip_type);
if (err != OK)
return ERR_CANT_CREATE;
_sock->set_blocking_enabled(false);
_sock->set_reuse_address_enabled(true);
err = _sock->bind(p_bind_address, p_port);
if (err != OK) {
stop();
return err;
}
bind_address = p_bind_address;
bind_port = p_port;
return OK;
}
bool UDPServer::is_listening() const {
ERR_FAIL_COND_V(!_sock.is_valid(), false);
return _sock->is_open();
}
bool UDPServer::is_connection_available() const {
ERR_FAIL_COND_V(!_sock.is_valid(), false);
if (!_sock->is_open())
return false;
return pending.size() > 0;
}
void UDPServer::set_max_pending_connections(int p_max) {
ERR_FAIL_COND_MSG(p_max < 0, "Max pending connections value must be a positive number (0 means refuse new connections).");
max_pending_connections = p_max;
while (p_max > pending.size()) {
List<Peer>::Element *E = pending.back();
if (!E) {
break;
}
memdelete(E->get().peer);
pending.erase(E);
}
}
int UDPServer::get_max_pending_connections() const {
return max_pending_connections;
}
Ref<PacketPeerUDP> UDPServer::take_connection() {
Ref<PacketPeerUDP> conn;
if (!is_connection_available()) {
return conn;
}
Peer peer = pending[0];
pending.pop_front();
peers.push_back(peer);
return peer.peer;
}
void UDPServer::remove_peer(IP_Address p_ip, int p_port) {
Peer peer;
peer.ip = p_ip;
peer.port = p_port;
List<Peer>::Element *E = peers.find(peer);
if (E) {
peers.erase(E);
}
}
void UDPServer::stop() {
if (_sock.is_valid()) {
_sock->close();
}
bind_port = 0;
bind_address = IP_Address();
List<Peer>::Element *E = peers.front();
while (E) {
E->get().peer->disconnect_shared_socket();
E = E->next();
}
E = pending.front();
while (E) {
E->get().peer->disconnect_shared_socket();
memdelete(E->get().peer);
E = E->next();
}
peers.clear();
pending.clear();
}
UDPServer::UDPServer() :
_sock(Ref<NetSocket>(NetSocket::create())) {
}
UDPServer::~UDPServer() {
stop();
}