UDPServer and PacketPeerUDP connect_to_host.

UDP sockets can be "connected" to filter packets from a specific source.
In case of a bound socket (e.g. server), a new socket can be created on
the same address/port that will receive all packets that are not
filtered by a more specific socket (e.g. the previously connect socket).

This way, a UDPServer can listen to new packets, and return a new
PacketPeerUDP when receiving one, knowing that is a "new client".

1 files changed, 119 insertions, 0 deletions

diff --git a/core/io/udp_server.cpp b/core/io/udp_server.cpp
new file mode 100644
index 0000000000..f041bf097f
--- /dev/null
+++ b/core/io/udp_server.cpp
@@ -0,0 +1,119 @@
+/*************************************************************************/
+/*  udp_server.cpp                                                       */
+/*************************************************************************/
+/*                       This file is part of:                           */
+/*                           GODOT ENGINE                                */
+/*                      https://godotengine.org                          */
+/*************************************************************************/
+/* Copyright (c) 2007-2019 Juan Linietsky, Ariel Manzur.                 */
+/* Copyright (c) 2014-2019 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("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);
+}
+
+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;
+
+	Error err = _sock->poll(NetSocket::POLL_TYPE_IN, 0);
+	return (err == OK);
+}
+
+Ref<PacketPeerUDP> UDPServer::take_connection() {
+
+	Ref<PacketPeerUDP> conn;
+	if (!is_connection_available()) {
+		return conn;
+	}
+
+	conn = Ref<PacketPeerUDP>(memnew(PacketPeerUDP));
+	conn->connect_socket(_sock);
+	_sock = Ref<NetSocket>(NetSocket::create());
+	listen(bind_port, bind_address);
+	return conn;
+}
+
+void UDPServer::stop() {
+
+	if (_sock.is_valid()) {
+		_sock->close();
+	}
+	bind_port = 0;
+	bind_address = IP_Address();
+}
+
+UDPServer::UDPServer() :
+		_sock(Ref<NetSocket>(NetSocket::create())) {
+}
+
+UDPServer::~UDPServer() {
+
+	stop();
+}