openmohaa/code/gamespy/serverbrowsing/sb_serverbrowsing.c

#include "sb_internal.h"
#include "sb_ascii.h"
#include "../natneg/natneg.h"

//Future Versions:
//ICMP Ping support (icmp engine)


//internal callback proxy for server list
static void ListCallback(SBServerList *serverlist, SBListCallbackReason reason, SBServer server, void *instance)
{
	ServerBrowser sb = (ServerBrowser)instance;
	switch (reason)
	{
	case slc_serveradded:
		sb->BrowserCallback(sb, sbc_serveradded, server, sb->instance);
		if ((server->state & (STATE_BASICKEYS|STATE_FULLKEYS)) == 0 || (server->state & STATE_VALIDPING) == 0) //we need to do an update
		{
			// Don't update if an update is already pending
			if (server->state & (STATE_PENDINGBASICQUERY|STATE_PENDINGFULLQUERY|STATE_PENDINGICMPQUERY))
				break;

			if (!sb->dontUpdate) //if this flag is set, we don't want to trigger updates
			{
				int qtype;
				if (server->flags & UNSOLICITED_UDP_FLAG)
				{
					if (sb->list.state == sl_lanbrowse || sb->engine.numserverkeys == 0)
						qtype = QTYPE_FULL;
					else
						qtype = QTYPE_BASIC;
				} else
					qtype = QTYPE_ICMP; //we can only do an ICMP query

				if (serverlist->backendgameflags & QR2_USE_QUERY_CHALLENGE)
					SBQueryEngineUpdateServer(&sb->engine, server, 0, qtype, SBTrue);
				else
					SBQueryEngineUpdateServer(&sb->engine, server, 0, qtype, SBFalse);

			}
		}
		break; 
	case slc_serverupdated:
		if ((server->state & (STATE_BASICKEYS|STATE_FULLKEYS|STATE_VALIDPING)) == 0) //if it was updated, but with no data, then the update failed!
			sb->BrowserCallback(sb, sbc_serverupdatefailed, server, sb->instance);
		else
			sb->BrowserCallback(sb, sbc_serverupdated, server, sb->instance);
		break;
	case slc_serverdeleted:
		if ((server->state & (STATE_PENDINGBASICQUERY|STATE_PENDINGFULLQUERY|STATE_PENDINGICMPQUERY)) != 0) 
			SBQueryEngineRemoveServerFromFIFOs(&sb->engine, server);
		sb->BrowserCallback(sb, sbc_serverdeleted, server, sb->instance);
		break;
	case slc_initiallistcomplete:
		if (sb->disconnectFlag)
			SBServerListDisconnect(serverlist);
		// If there aren't any servers to query, call the completed callback
		if (ArrayLength(serverlist->servers)==0 || sb->engine.querylist.count==0)
			sb->BrowserCallback(sb, sbc_updatecomplete, NULL, sb->instance);
		break;
	case slc_disconnected:
		break; 
	case slc_queryerror:
		sb->BrowserCallback(sb, sbc_queryerror, NULL, sb->instance);
		break;
	case slc_publicipdetermined:
		SBQueryEngineSetPublicIP(&sb->engine, sb->list.mypublicip);
		break;
	case slc_serverchallengereceived:
		break;
	}
	if (server != NULL && server->publicip == sb->triggerIP && server->publicport == sb->triggerPort)
		sb->triggerIP = 0; //clear the trigger
}

//internal callback proxy for query engine
static void EngineCallback(SBQueryEnginePtr engine, SBQueryEngineCallbackReason reason, SBServer server, void *instance)
{
	ServerBrowser sb = (ServerBrowser)instance;
	switch (reason)
	{
	case qe_updatefailed:
		sb->BrowserCallback(sb, sbc_serverupdatefailed, server, sb->instance);
		break;
	case qe_updatesuccess:
		sb->BrowserCallback(sb, sbc_serverupdated, server, sb->instance);
		break;
	case qe_engineidle:
		sb->BrowserCallback(sb, sbc_updatecomplete, server, sb->instance);
		break;
	case qe_challengereceived:
		sb->BrowserCallback(sb, sbc_serverchallengereceived, server, sb->instance);
		//challenge received will return instead of break - since the game has not yet been updated
		return;
	}
	if (server != NULL && server->publicip == sb->triggerIP && server->publicport == sb->triggerPort)
		sb->triggerIP = 0; //clear the trigger
		
	GSI_UNUSED(engine);
}



ServerBrowser ServerBrowserNewA(const char *queryForGamename, const char *queryFromGamename, const char *queryFromKey, int queryFromVersion, int maxConcUpdates, int queryVersion, SBBool lanBrowse, ServerBrowserCallback callback, void *instance)
{
	ServerBrowser sb;
	if(lanBrowse == SBFalse)
	{
		if(__GSIACResult != GSIACAvailable)
			return NULL;
	}
	
	sb = (ServerBrowser)gsimalloc(sizeof(struct _ServerBrowser));
	if (sb == NULL)
		return NULL;
	sb->BrowserCallback = callback;
	sb->ConnectCallback = NULL;
	sb->instance = instance;
	sb->dontUpdate = SBFalse;
	SBServerListInit(&sb->list, queryForGamename, queryFromGamename, queryFromKey, queryFromVersion, lanBrowse, ListCallback, sb);
	SBQueryEngineInit(&sb->engine, maxConcUpdates, queryVersion, lanBrowse, EngineCallback, sb);
	return sb;
}
#ifdef GSI_UNICODE
ServerBrowser ServerBrowserNewW(const unsigned short *queryForGamename, const unsigned short *queryFromGamename, const unsigned short *queryFromKey, int queryFromVersion, int maxConcUpdates, int queryVersion, SBBool lanBrowse, ServerBrowserCallback callback, void *instance)
{
	char forGameName_A[255];
	char fromGameName_A[255];
	char fromGameKey_A[255];

	assert(queryForGamename != NULL);
	assert(queryFromGamename != NULL);
	assert(queryFromKey != NULL);

	UCS2ToAsciiString(queryForGamename, forGameName_A);
	UCS2ToAsciiString(queryFromGamename, fromGameName_A);
	UCS2ToAsciiString(queryFromKey, fromGameKey_A);
	return ServerBrowserNewA(forGameName_A, fromGameName_A, fromGameKey_A, queryFromVersion, maxConcUpdates, queryVersion, lanBrowse, callback, instance);
}
#endif

void ServerBrowserFree(ServerBrowser sb)
{
	SBServerListCleanup(&sb->list);
	SBEngineCleanup(&sb->engine);
    NNFreeNegotiateList();
	gsifree(sb);
}

//internal version that allows passing of additional options
SBError ServerBrowserBeginUpdate2(ServerBrowser sb, SBBool async, SBBool disconnectOnComplete, const unsigned char *basicFields, int numBasicFields, const char *serverFilter, int updateOptions, int maxServers)
{
	char keyList[MAX_FIELD_LIST_LEN] = "";	
	int listLen = 0;
	int i;
	int keylen;
	SBError err;

	sb->disconnectFlag = disconnectOnComplete;
	//clear this out in case it was already set
	sb->engine.numserverkeys = 0;
	//build the key list...
	for (i = 0 ; i < numBasicFields ; i++)
	{
		keylen = (int)strlen(qr2_registered_key_list[basicFields[i]]);
		if (listLen + keylen + 1 >= MAX_FIELD_LIST_LEN)
			break; //can't add this field, too long
		listLen += sprintf(keyList + listLen, "\\%s", qr2_registered_key_list[basicFields[i]]);
		//add to the engine query list
		SBQueryEngineAddQueryKey(&sb->engine, basicFields[i]);
	}

#if defined(SN_SYSTEMS) && defined(SB_ICMP_SUPPORT)
	{
		// reset SNSystems internal ICMP ping structures
		sndev_set_ping_reset_type optval;
		optval.timeout_ms = MAX_QUERY_MSEC; // this gets rounded up to 3 sec
		optval.reserved = 0;
		sndev_set_options(0, SN_DEV_SET_PING_RESET, &optval, sizeof(optval));
	}
#endif

	err = SBServerListConnectAndQuery(&sb->list, keyList, serverFilter, updateOptions, maxServers);
	if (err != sbe_noerror)
		return err;
	
	if (!async) //loop while we are still getting the main list and the engine is updating...
	{
		while ((sb->list.state == sl_mainlist) || ((sb->engine.querylist.count > 0) && (err == sbe_noerror)))
		{
			msleep(10);
			err = ServerBrowserThink(sb);
		}
	}
	return err;
}


SBError ServerBrowserUpdateA(ServerBrowser sb, SBBool async, SBBool disconnectOnComplete, const unsigned char *basicFields, int numBasicFields, const char *serverFilter)
{
	return ServerBrowserBeginUpdate2(sb, async, disconnectOnComplete, basicFields, numBasicFields, serverFilter, 0, 0);
}
#ifdef GSI_UNICODE
SBError ServerBrowserUpdateW(ServerBrowser sb, SBBool async, SBBool disconnectOnComplete, const unsigned char *basicFields, int numBasicFields, const unsigned short *serverFilter)
{
	char serverFilter_A[1024];
	if (serverFilter != NULL)
		UCS2ToUTF8String(serverFilter, serverFilter_A);
	return ServerBrowserUpdateA(sb, async, disconnectOnComplete, basicFields, numBasicFields, (serverFilter != NULL) ? serverFilter_A:NULL);
}
#endif

SBError ServerBrowserLimitUpdateA(ServerBrowser sb, SBBool async, SBBool disconnectOnComplete, const unsigned char *basicFields, int numBasicFields, const char *serverFilter, int maxServers)
{
	return ServerBrowserBeginUpdate2(sb, async, disconnectOnComplete, basicFields, numBasicFields, serverFilter, LIMIT_RESULT_COUNT, maxServers);
}
#ifdef GSI_UNICODE
SBError ServerBrowserLimitUpdateW(ServerBrowser sb, SBBool async, SBBool disconnectOnComplete, const unsigned char *basicFields, int numBasicFields, const unsigned short *serverFilter, int maxServers)
{
	char serverFilter_A[1024];
	if (serverFilter != NULL)
		UCS2ToUTF8String(serverFilter, serverFilter_A);
	return ServerBrowserLimitUpdateA(sb, async, disconnectOnComplete, basicFields, numBasicFields, (serverFilter != NULL) ? serverFilter_A:NULL, maxServers);
}
#endif

SBError ServerBrowserLANUpdate(ServerBrowser sb, SBBool async, unsigned short startSearchPort, unsigned short endSearchPort)
{
	SBError err = sbe_noerror;
	ServerBrowserHalt(sb);
	SBServerListGetLANList(&sb->list, startSearchPort, endSearchPort, sb->engine.queryversion);
	if (!async)
	{
		while ((sb->list.state == sl_lanbrowse) || ((sb->engine.querylist.count > 0) && (err == sbe_noerror)))
		{
			msleep(10);
			err = ServerBrowserThink(sb);
		}
	}
	return err;
}

static SBError WaitForTriggerUpdate(ServerBrowser sb, SBBool viaMaster)
{
	SBError err = sbe_noerror;
	//wait until info is received for the triggerIP
	while (sb->triggerIP != 0 && err == sbe_noerror)
	{
		msleep(10);
		err = ServerBrowserThink(sb);
		if (viaMaster && sb->list.state == sb_disconnected) //we were supposed to get from master, and it's disconnected
			break;		
	}
	return err;

}


SBError ServerBrowserSendMessageToServerA(ServerBrowser sb, const char *ip, unsigned short port, const char *data, int len)
{
	return SBSendMessageToServer(&sb->list, inet_addr(ip), htons(port), data, len);
}
#ifdef GSI_UNICODE
SBError ServerBrowserSendMessageToServerW(ServerBrowser sb, const unsigned short *ip, unsigned short port, const char *data, int len)
{
	char ip_A[128];
	UCS2ToAsciiString(ip, ip_A);
	return ServerBrowserSendMessageToServerA(sb, ip_A, port, data, len);
}
#endif

SBError ServerBrowserSendNatNegotiateCookieToServerA(ServerBrowser sb, const char *ip, unsigned short port, int cookie)
{
	return SBSendNatNegotiateCookieToServer(&sb->list, inet_addr(ip), htons(port), cookie);
}
#ifdef GSI_UNICODE
SBError ServerBrowserSendNatNegotiateCookieToServerW(ServerBrowser sb, const unsigned short *ip, unsigned short port, int cookie)
{
	char ip_A[128];
	UCS2ToAsciiString(ip, ip_A);
	return ServerBrowserSendNatNegotiateCookieToServerA(sb, ip_A, port, cookie);
}
#endif

static void NatNegProgressCallback(NegotiateState state, void *userdata)
{
	// we don't do anything here
	GSI_UNUSED(state);
	GSI_UNUSED(userdata);
}

static void NatNegCompletedCallback(NegotiateResult result, SOCKET gamesocket, struct sockaddr_in *remoteaddr, void *userdata)
{
	ServerBrowser sb = (ServerBrowser)userdata;

	if(result == nr_success)
	{
		sb->ConnectCallback(sb, sbcs_succeeded, gamesocket, remoteaddr, sb->instance);
	}
	else
	{
		sb->ConnectCallback(sb, sbcs_failed, INVALID_SOCKET, NULL, sb->instance);
	}

	sb->ConnectCallback = NULL;

	GSI_UNUSED(remoteaddr);
}

SBError ServerBrowserConnectToServer(ServerBrowser sb, SBServer server, SBConnectToServerCallback callback)
{
	SBError sbError;
	NegotiateError nnError;
	int cookie;

	if((sb == NULL) || (server == NULL) || (callback == NULL))
		return sbe_paramerror;

	if(sb->ConnectCallback != NULL)
		return sbe_connecterror;

	// for now, always do natneg

	// send a cookie to the server
	Util_RandSeed((unsigned long)current_time());
	cookie = Util_RandInt(GSI_MIN_I32, GSI_MAX_I32);
	sbError = ServerBrowserSendNatNegotiateCookieToServerA(sb, SBServerGetPublicAddress(server), SBServerGetPublicQueryPort(server), cookie);
	if(sbError != sbe_noerror)
		return sbError;

	// start the nn
	nnError = NNBeginNegotiation(cookie, 0, NatNegProgressCallback, NatNegCompletedCallback, sb);
	if(nnError != ne_noerror)
		return sbe_connecterror;

	sb->ConnectCallback = callback;

	return sbe_noerror;
}

SBError ServerBrowserAuxUpdateIPA(ServerBrowser sb, const char *ip, unsigned short port, SBBool viaMaster, SBBool async, SBBool fullUpdate)
{
	
	SBError err = sbe_noerror;
	sb->dontUpdate = SBTrue;

	if (!viaMaster) //do an engine query
	{
		SBServer server;
		int i;
		SBBool usequerychallenge = (sb->list.backendgameflags & QR2_USE_QUERY_CHALLENGE) > 0 ? SBTrue:SBFalse;

		//need to see if the server exists...
		i = SBServerListFindServerByIP(&sb->list, inet_addr(ip), htons(port));
		if (i == -1)
		{
			server = SBQueryEngineUpdateServerByIP(&sb->engine, ip, port, 1, (fullUpdate) ? QTYPE_FULL : QTYPE_BASIC, usequerychallenge);
			SBServerListAppendServer(&sb->list, server);
		}
		else
			server = SBServerListNth(&sb->list, i);

		// Don't overwrite the existing update, otherwise the response for the first update
		// will be mistaken as the response for the second update.  (Which is bad if they have different update parameters.)
		if (server->state & (STATE_PENDINGBASICQUERY|STATE_PENDINGFULLQUERY|STATE_PENDINGICMPQUERY))
			return sbe_duplicateupdateerror;
		else
			SBQueryEngineUpdateServer(&sb->engine, server, 1, (fullUpdate) ? QTYPE_FULL : QTYPE_BASIC, usequerychallenge);

	} else //do a master update
	{
		err = SBGetServerRulesFromMaster(&sb->list, inet_addr(ip), htons(port));	
		//this will add the server itself..
	}
	if (!async && err == sbe_noerror)
	{
		sb->triggerIP = inet_addr(ip);
		sb->triggerPort = htons(port);
		err = WaitForTriggerUpdate(sb, viaMaster);
	}
	sb->dontUpdate = SBFalse;
	return err;
}
#ifdef GSI_UNICODE
SBError ServerBrowserAuxUpdateIPW(ServerBrowser sb, const unsigned short *ip, unsigned short port, SBBool viaMaster, SBBool async, SBBool fullUpdate)
{
	char ip_A[128];
	UCS2ToAsciiString(ip, ip_A);
	return ServerBrowserAuxUpdateIPA(sb, ip_A, port, viaMaster, async, fullUpdate);
}
#endif

SBError ServerBrowserAuxUpdateServer(ServerBrowser sb, SBServer server, SBBool async, SBBool fullUpdate)
{
	SBBool viaMaster;
	SBError err = sbe_noerror;
	SBBool usequerychallenge = (sb->list.backendgameflags & QR2_USE_QUERY_CHALLENGE) > 0 ? SBTrue:SBFalse;

	sb->dontUpdate = SBTrue;
	
	if (server->flags & UNSOLICITED_UDP_FLAG) //do an engine query
	{
		//remove from the existing update lists if present
		SBQueryEngineRemoveServerFromFIFOs(&sb->engine, server);
		SBQueryEngineUpdateServer(&sb->engine, server, 1, (fullUpdate) ? QTYPE_FULL : QTYPE_BASIC, usequerychallenge);
		viaMaster = SBFalse;
	} else //do a master update
	{
		err = SBGetServerRulesFromMaster(&sb->list, server->publicip, server->publicport);	
		viaMaster = SBTrue;
	}
	if (!async && err == sbe_noerror)
	{
		sb->triggerIP = server->publicip;
		sb->triggerPort = server->publicport;
		err = WaitForTriggerUpdate(sb, viaMaster);
	}
	sb->dontUpdate = SBFalse;
	return err;
}

void ServerBrowserRemoveIPA(ServerBrowser sb, const char *ip, unsigned short port)
{
	int i = SBServerListFindServerByIP(&sb->list, inet_addr(ip), htons(port));
	if (i != -1)
		SBServerListRemoveAt(&sb->list, i);
}
#ifdef GSI_UNICODE
void ServerBrowserRemoveIPW(ServerBrowser sb, const unsigned short *ip, unsigned short port)
{
	char ip_A[128];
	UCS2ToAsciiString(ip, ip_A);
	ServerBrowserRemoveIPA(sb, ip_A, port);
}
#endif

void ServerBrowserRemoveServer(ServerBrowser sb, SBServer server)
{
	int i = SBServerListFindServer(&sb->list, server);
	if (i != -1)
		SBServerListRemoveAt(&sb->list, i);
}

SBError ServerBrowserThink(ServerBrowser sb)
{
	NNThink();
	SBQueryEngineThink(&sb->engine);
	return SBListThink(&sb->list);
}

void ServerBrowserHalt(ServerBrowser sb)
{
	//stop the list
	SBServerListDisconnect(&sb->list);
	//stop the query engine...
	SBEngineHaltUpdates(&sb->engine);

}

void ServerBrowserClear(ServerBrowser sb)
{
	ServerBrowserHalt(sb);
	SBServerListClear(&sb->list);
}

const char *ServerBrowserErrorDescA(ServerBrowser sb, SBError error)
{
	switch (error)
	{
	case sbe_noerror:
		return "None";
		//break;
	case sbe_socketerror:
		return "Socket creation error";
		//break;
	case sbe_dnserror:
		return "DNS lookup error";
		//break;
	case sbe_connecterror:
		return "Connection failed";
		//break;
	case sbe_dataerror:
		return "Data stream error";
		//break;
	case sbe_allocerror:
		return "Memory allocation error";
		//break;
	case sbe_paramerror:
		return "Function parameter error";
		//break;
	case sbe_duplicateupdateerror:
		return "Duplicate update request error";
		//break;
	}

	GSI_UNUSED(sb);
	return "";
}
#ifdef GSI_UNICODE
const unsigned short *ServerBrowserErrorDescW(ServerBrowser sb, SBError error)
{
	switch (error)
	{
	case sbe_noerror:
		return L"None";
		break;
	case sbe_socketerror:
		return L"Socket creation error";
		break;
	case sbe_dnserror:
		return L"DNS lookup error";
		break;
	case sbe_connecterror:
		return L"Connection failed";
		break;
	case sbe_dataerror:
		return L"Data stream error";
		break;
	case sbe_allocerror:
		return L"Memory allocation error";
		break;
	case sbe_paramerror:
		return L"Function parameter error";
		break;
	case sbe_duplicateupdateerror:
		return L"Duplicate update request error";
		break;
	}
	return L"";
	
	GSI_UNUSED(sb);
}
#endif

const char *ServerBrowserListQueryErrorA(ServerBrowser sb)
{
	return SBLastListErrorA(&sb->list);
}
#ifdef GSI_UNICODE
const unsigned short *ServerBrowserListQueryErrorW(ServerBrowser sb)
{
	return SBLastListErrorW(&sb->list);
}
#endif

SBState ServerBrowserState(ServerBrowser sb)
{
	if (sb->engine.querylist.count > 0)
		return sb_querying;
	if (sb->list.state == sl_mainlist || sb->list.state == sl_lanbrowse)
		return sb_listxfer;
	if (sb->list.state == sl_disconnected)
		return sb_disconnected;
	return sb_connected;
}

int ServerBrowserPendingQueryCount(ServerBrowser sb)
{
	return sb->engine.querylist.count + sb->engine.pendinglist.count;
}

SBServer ServerBrowserGetServer(ServerBrowser sb, int index)
{
	return SBServerListNth(&sb->list, index);
}

SBServer ServerBrowserGetServerByIPA(ServerBrowser sb, const char* ip, unsigned short port)
{
	int anIndex = -1;
	goa_uint32 anIP = 0;
	unsigned short aPortNBO = htons(port);

	anIP = inet_addr(ip);
	anIndex = SBServerListFindServerByIP(&sb->list, anIP, aPortNBO);
	if (anIndex != -1)
		return SBServerListNth(&sb->list, anIndex);
	return NULL;
}
#ifdef GSI_UNICODE
SBServer ServerBrowserGetServerByIPW(ServerBrowser sb, const unsigned short* ip, unsigned short port)
{
	char ip_A[20];

	if(ip == NULL || wcslen(ip) > 16)
		return NULL;

	UCS2ToAsciiString(ip, ip_A);
	return ServerBrowserGetServerByIPA(sb, ip_A, port);
}
#endif

int ServerBrowserCount(ServerBrowser sb)
{
	return SBServerListCount(&sb->list);
}

void ServerBrowserSortA(ServerBrowser sb, SBBool ascending, const char *sortkey, SBCompareMode comparemode)
{
	SortInfo info;
	info.comparemode = comparemode;
#ifdef GSI_UNICODE
	GS_ASSERT(sortkey != NULL && _tcslen((const unsigned short *)sortkey) <= SORTKEY_LENGTH);
	_tcscpy(info.sortkey, (const unsigned short *)sortkey);
#else
	GS_ASSERT(sortkey != NULL && _tcslen(sortkey) <= SORTKEY_LENGTH);
	_tcscpy(info.sortkey, sortkey);
#endif
	SBServerListSort(&sb->list, ascending, info);
}
#ifdef GSI_UNICODE
void ServerBrowserSortW(ServerBrowser sb, SBBool ascending, const unsigned short *sortkey, SBCompareMode comparemode)
{
	char sortkey_A[255];
	UCS2ToUTF8String(sortkey, sortkey_A);
	//struct SortInfo info;
	//info.comparemode = comparemode;
	//GS_ASSERT(sortkey != NULL && _tcslen((const unsigned short *)sortkey) <= SORTKEY_LENGTH);
	//_tcscpy(info.sortkey, (const unsigned short *)sortkey_A);
	//SBServerListSort(&sb->list, ascending, info);
	ServerBrowserSortA(sb, ascending, sortkey_A, comparemode);
}
#endif

char *ServerBrowserGetMyPublicIP(ServerBrowser sb)
{
	return (char *)inet_ntoa(*(struct in_addr *)&sb->list.mypublicip);
}

unsigned int ServerBrowserGetMyPublicIPAddr(ServerBrowser sb)
{
	return sb->list.mypublicip;
}

void ServerBrowserDisconnect(ServerBrowser sb)
{
	SBServerListDisconnect(&sb->list);
}

// Allows the user to specify a broadcast address for LAN hosting
void ServerBrowserLANSetLocalAddr(ServerBrowser sb, const char* theAddr)
{
	sb->list.mLanAdapterOverride = theAddr;
}


/* SBServerGetConnectionInfo
----------------
Check if Nat Negotiation is requires, based off whether it is a lan game, public ip present and several other facts. 
Returns an IP string to use for NatNeg, or direct connect if possible
Work for subsequent connection to this server, One of three results will occur
i) Lan game, connect using ipstring
2) Internet game, connect using ipstring
3) nat traversal required, perform nat negotiation using Nat SDK and this ipstring before connecting. 

return sb_true if further processing is required... i.e. NAT.   sb_false if not.
fills an IP string
*/
SBBool SBServerGetConnectionInfo(ServerBrowser gSB, SBServer server, gsi_u16 PortToConnectTo, char *ipstring)
{
	SBBool natneg = SBFalse;
    if (SBServerHasPrivateAddress(server) == SBTrue && (SBServerGetPublicInetAddress(server) == ServerBrowserGetMyPublicIPAddr(gSB)))
	{

		//directly connect to private IP (LAN)
		sprintf(ipstring,"%s:%d", SBServerGetPrivateAddress(server),PortToConnectTo );
 
	}
	else
	if ((SBServerDirectConnect(server) == SBTrue )&& (SBServerHasPrivateAddress(server) == SBFalse))
	{
            //can directly connect to public IP, no negotiation required
			sprintf(ipstring,"%s:%d", SBServerGetPrivateAddress(server),	PortToConnectTo );
	}
	else
	{
		//Nat Negotiation required
		natneg = SBTrue;
		sprintf(ipstring,"%s:%d", SBServerGetPublicAddress(server),	SBServerGetPublicQueryPort	(server) );
	}
	return natneg;
}