godot/platform/windows/packet_peer_udp_winsock.cpp

/*************************************************************************/
/*  packet_peer_udp_winsock.cpp                                          */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
/*                    http://www.godotengine.org                         */
/*************************************************************************/
/* Copyright (c) 2007-2016 Juan Linietsky, Ariel Manzur.                 */
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/* distribute, sublicense, and/or sell copies of the Software, and to    */
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/* the following conditions:                                             */
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/* The above copyright notice and this permission notice shall be        */
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/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
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/*************************************************************************/
#include "packet_peer_udp_winsock.h"

#include <winsock2.h>
#include <ws2tcpip.h>

#include "drivers/unix/socket_helpers.h"

int PacketPeerUDPWinsock::get_available_packet_count() const {

	Error err = const_cast<PacketPeerUDPWinsock*>(this)->_poll(false);
	if (err!=OK)
		return 0;

	return queue_count;
}

Error PacketPeerUDPWinsock::get_packet(const uint8_t **r_buffer,int &r_buffer_size) const{

	Error err = const_cast<PacketPeerUDPWinsock*>(this)->_poll(false);
	if (err!=OK)
		return err;
	if (queue_count==0)
		return ERR_UNAVAILABLE;

	uint32_t size;
	uint8_t type;
	rb.read(&type, 1, true);
	if (type == IP_Address::TYPE_IPV4) {
		rb.read((uint8_t*)&packet_ip.field8,4,true);
		packet_ip.type = IP_Address::TYPE_IPV4;
	} else {
		rb.read((uint8_t*)&packet_ip.field8,16,true);
		packet_ip.type = IP_Address::TYPE_IPV6;
	};
	rb.read((uint8_t*)&packet_port,4,true);
	rb.read((uint8_t*)&size,4,true);
	rb.read(packet_buffer,size,true);
	--queue_count;
	*r_buffer=packet_buffer;
	r_buffer_size=size;
	return OK;

}
Error PacketPeerUDPWinsock::put_packet(const uint8_t *p_buffer,int p_buffer_size){

	int sock = _get_socket();
	ERR_FAIL_COND_V( sock == -1, FAILED );
	struct sockaddr_storage addr;
	size_t addr_size = _set_sockaddr(&addr, peer_addr, peer_port);

	_set_blocking(true);

	errno = 0;
	int err;
	while ( (err = sendto(sock, (const char*)p_buffer, p_buffer_size, 0, (struct sockaddr*)&addr, addr_size)) != p_buffer_size) {

		if (WSAGetLastError() != WSAEWOULDBLOCK) {
			return FAILED;
		};
	}

	return OK;
}

int PacketPeerUDPWinsock::get_max_packet_size() const{

	return 512; // uhm maybe not
}


void PacketPeerUDPWinsock::_set_blocking(bool p_blocking) {
	//am no windows expert
	//hope this is the right thing

	if (blocking==p_blocking)
		return;

	blocking=p_blocking;
	unsigned long par = blocking?0:1;
	if (ioctlsocket(sockfd, FIONBIO, &par)) {
		perror("setting non-block mode");
		//close();
		//return -1;
	};
}

Error PacketPeerUDPWinsock::listen(int p_port, int p_recv_buffer_size) {

	close();
	int sock = _get_socket();
	if (sock == -1 )
		return ERR_CANT_CREATE;

	if(ip_type == IP_Address::TYPE_IPV6) {
		// Use IPv6 only socket
		int yes = 1;
		if(setsockopt(sockfd, IPPROTO_IPV6, IPV6_V6ONLY, (const char*)&yes, sizeof(yes)) != 0) {
				WARN_PRINT("Unable to unset IPv4 address mapping over IPv6");
		}
	}

	struct sockaddr_storage addr = {0};
	size_t addr_size = _set_listen_sockaddr(&addr, p_port, ip_type, NULL);

	if (bind(sock, (struct sockaddr*)&addr, addr_size) == -1 ) {
		close();
		return ERR_UNAVAILABLE;
	}

	blocking=true;

	printf("UDP Connection listening on port %i\n", p_port);
	rb.resize(nearest_shift(p_recv_buffer_size));
	return OK;
}

void PacketPeerUDPWinsock::close(){

	if (sockfd != -1)
		::closesocket(sockfd);
	sockfd=-1;
	rb.resize(8);
	queue_count=0;
}


Error PacketPeerUDPWinsock::wait() {

	return _poll(true);
}
Error PacketPeerUDPWinsock::_poll(bool p_wait) {


	_set_blocking(p_wait);


	struct sockaddr_storage from = {0};
	int len = sizeof(struct sockaddr_storage);
	int ret;
	while ( (ret = recvfrom(sockfd, (char*)recv_buffer, MIN((int)sizeof(recv_buffer),MAX(rb.space_left()-12, 0)), 0, (struct sockaddr*)&from, &len)) > 0) {

		uint32_t port = 0;

		if (from.ss_family == AF_INET) {
			uint8_t type = (uint8_t)IP_Address::TYPE_IPV4;
			rb.write(&type, 1);
			struct sockaddr_in* sin_from = (struct sockaddr_in*)&from;
			rb.write((uint8_t*)&sin_from->sin_addr, 4);
			port = ntohs(sin_from->sin_port);

		} else if (from.ss_family == AF_INET6) {

			uint8_t type = (uint8_t)IP_Address::TYPE_IPV6;
			rb.write(&type, 1);

			struct sockaddr_in6* s6_from = (struct sockaddr_in6*)&from;
			rb.write((uint8_t*)&s6_from->sin6_addr, 16);

			port = ntohs(s6_from->sin6_port);

		} else {
			// WARN_PRINT("Ignoring packet with unknown address family");
			uint8_t type = (uint8_t)IP_Address::TYPE_NONE;
			rb.write(&type, 1);
		};

		rb.write((uint8_t*)&port, 4);
		rb.write((uint8_t*)&ret, 4);
		rb.write(recv_buffer, ret);

		len = sizeof(struct sockaddr_storage);
		++queue_count;
	};

	if (ret == SOCKET_ERROR){
		int error = WSAGetLastError();

		if (error == WSAEWOULDBLOCK){
			// Expected when doing non-blocking sockets, retry later.
		}
		else if (error == WSAECONNRESET){
			// If the remote target does not accept messages, this error may occur, but is harmless.
			// Once the remote target gets available, this message will disappear for new messages.
		}
		else
		{
			close();
			return FAILED;
		}
	}


	if (ret == 0) {
		close();
		return FAILED;
	};


	return OK;
}

bool PacketPeerUDPWinsock::is_listening() const{

	return sockfd!=-1;
}

IP_Address PacketPeerUDPWinsock::get_packet_address() const {

	return packet_ip;
}

int PacketPeerUDPWinsock::get_packet_port() const{

	return packet_port;
}

int PacketPeerUDPWinsock::_get_socket() {

	if (sockfd != -1)
		return sockfd;

	sockfd = _socket_create(ip_type, SOCK_DGRAM, IPPROTO_UDP);

	return sockfd;
}


void PacketPeerUDPWinsock::set_send_address(const IP_Address& p_address,int p_port) {

	peer_addr=p_address;
	peer_port=p_port;
}

void PacketPeerUDPWinsock::make_default() {

	PacketPeerUDP::_create = PacketPeerUDPWinsock::_create;
};


PacketPeerUDP* PacketPeerUDPWinsock::_create() {

	return memnew(PacketPeerUDPWinsock);
};


PacketPeerUDPWinsock::PacketPeerUDPWinsock() {

	sockfd=-1;
	packet_port=0;
	queue_count=0;
	peer_port=0;
	ip_type = IP_Address::TYPE_ANY;
}

PacketPeerUDPWinsock::~PacketPeerUDPWinsock() {

	close();
}