Thread: socket, udp,Halflife Server

First of all, hi all

Well, i coded a udp socket with a tutorial, which i want to connect to an HL server to get some Infos(POlayers,map,...)

my program:
---------------------------------------------------------------------------------------
#include <winsock2.h>
#include <stdio.h>
#include <stdlib.h>

//Prototypen
int startWinsock(void);
int main()
{
long rc;
int a= -1;
SOCKET s;
char buf[256];
SOCKADDR_IN addr;
SOCKADDR_IN remoteAddr;
int remoteAddrLen=sizeof(SOCKADDR_IN);

rc=startWinsock();
if(rc!=0)
{
printf("Fehler: startWinsock, fehler code: %d\n",rc); return 1;
sleep(1000);
}
else
{
printf("Winsock gestartet!\n");
sleep(1000);
}

//UDP Socket erstellen
s=socket(AF_INET,SOCK_DGRAM,0);
if(s==INVALID_SOCKET)
{ printf("Fehler: Der Socket konnte nicht erstellt werden, fehler code: %d\n",WSAGetLastError());
sleep(1000);
return 1;
}
else
{printf("UDP Socket erstellt!\n");
sleep(1000);
}
// addr vorbereiten
addr.sin_family=AF_INET;
addr.sin_port=htons(27016);
addr.sin_addr.s_addr=inet_addr("194.112.0.163");

rc=connect(s,(SOCKADDR*)&addr,sizeof(SOCKADDR_IN)) ;

//rc=sendto (s,buf,strlen(buf),0,(SOCKADDR*)&addr,sizeof(SOCKA DDR_IN));
rc=send(s,buf,strlen(buf),0);
if(rc==SOCKET_ERROR)
{
printf("Fehler: send, fehler code: %d\n",WSAGetLastError());
sleep(1000);
return 1;
}
else
{
printf("%d Bytes gesendet!\n", rc);
sleep(1000);
}
//rc=recvfrom(s,buf,256,0,(SOCKADDR*)&remoteAddr,&re moteAddrLen);
rc=recv(s,buf,256,0);
if(rc==SOCKET_ERROR)
{
printf("Fehler: recvfrom, fehler code: %d\n",WSAGetLastError());
sleep(1000);
return 1;
}
else
{
printf("%d Bytes empfangen!\n", rc);
sleep(1000);
buf[rc]='\0';
printf("Empfangene Daten: %s\n",buf);
sleep(1000);
}
WSACleanup();
closesocket(s);
return 0;
}

int startWinsock(void)
{WSADATA wsa;
return WSAStartup(MAKEWORD(2,0),&wsa);
}
---------------------------------------------------------------------------------------here is a short snippet from hl server protocol txt:

Remote App sends a UDP packet to the server on the server's port (e.g., 127.0.0.1:27015):

The packet should start with 4 consecutive bytes of 255 (32-bit integer -1) and the string:

"challenge rcon\n".

The server will respond to the requesting system on the purported remote IP address and port with four 255's and:

"challenge rcon number\n" where number is an unsigned int32 number.

full txt file at :
http://www.chatbear.com/cgi-bin/boar...2&view=flatold

---------------------------------------------------------------------------------------

well, i dunno really what is ment ot how to sent it since im a beginner, i would appreciate your help alot, but if you are willing to help plz make it detailed, best would be to show whats to be done with the code

Thx in advance


Tolpan

> rc=recv(s,buf,256,0);
This does not guarantee that you'll receive all your bytes in one message

If you're expecting "hello world", you might on various runs of your program receive
"hello world"

"hello" " world"

"h" "e" "llo world"

etc etc
You need to re-assemble your expected message from several message fragments, if necessary

> The packet should start with 4 consecutive bytes of 255 (32-bit integer -1) and the string:
> "challenge rcon\n".
So start with a buffer containing
char expected[] = "0xFF" "0xFF" "0xFF" "0xFF" "challenge rcon\n"

Then you would do

Code:

if ( memcmp( buff, expected, 19 ) == 0 ) {
    // got the message!
}

This is but one way to test for the arrival of your expected message.

It's up to you to decide what to do if you don't get this message.

Thx alot for your help, i will try this tonight/tomorrow and im almost sure im gonna drop by in the near future with other stuff

Thx again


Tolpan