Thread: winsock server question?

hey guys!

first time here... hope to stay for long! cheers to everyone!

I found this example - this server serves only one client at a time,
what do I need to change to it allows multiple clients to connect to?

Code:

#ifndef _WINSOCKAPI_
#define _WINSOCKAPI_
#endif

#include <windows.h>
#include <winsock2.h>

#include <stdio.h>

// Declare the sockets we use.


SOCKET listeningSocket;
SOCKET connectedSocket;

int InitSockets(void)
{
  struct sockaddr *servAddr;
  struct sockaddr_in *inetServAddr;
  int error = 0;
  // Create the socket.
  listeningSocket = socket(AF_INET, SOCK_STREAM, 0);
  if(listeningSocket == INVALID_SOCKET) {
    printf("error: socket() failed");
    return –1;
  }
 
  // Allocate memory for the address structure and set it to zero.
  servAddr = (struct sockaddr *) malloc(sizeof(sockaddr));
  memset((char *) servAddr, 0, sizeof(sockaddr));
  
  // Fill the address structure.
  servAddr->sa_family = (u_short) AF_INET;
  inetServAddr = (struct sockaddr_in *) servAddr;
  inetServAddr->sin_port = htons((u_short) 9009);

  // Bind the address information to the socket.
  error = bind(listeningSocket, servAddr, sizeof(sockaddr));
  if(error == SOCKET_ERROR) {
    printf("error: bind() failed");
    free(servAddr);
    return –1;
  }

  free(servAddr);
  servAddr = NULL;
 
  // Listen for incoming connections. Queue only one connection.
  error = listen(listeningSocket, 1);
  if(error == SOCKET_ERROR)  {
    printf("error: listen() failed");
    return –1;
  }
  
  // Accept the connection. Accept is a blocking function.
  connectedSocket = accept(listeningSocket, NULL, NULL);
  if(connectedSocket == INVALID_SOCKET)


  void ServerProcess(void)
  {
     int connectionOpen;
     char buf[2];
     connectionOpen = 1;
  
    // Loop as long as connection is open.
    while(connectionOpen) {
       // Read the incoming data from the connected socket.
      if(recv(connectedSocket, buf, 2, 0)) {
        // Set the received letter to uppercase and
        // make sure the string ends after that by setting the next
        // byte to NULL.
        buf[0] = toupper(buf[0]);
        buf[1] = '\0';
        printf("Got message from client: %s\n", buf);
        // Send the feedback.
        if(send(connectedSocket, buf, 2, 0) == SOCKET_ERROR) {
          connectionOpen = 0;
        }
      }
      else {
          closesocket(connectedSocket);
          connectionOpen = 0;
      }
   }
}
int main(void) {

  if(NET_WinSockInitialize() != 0) {
     printf("Critical error, quitting\n");
     return –1;
  }
  
  if(InitSockets() != 0) {
     printf("Critical error, quitting\n");
     WSACleanup();
     return –1;
  }

  ServerProcess();
  WSACleanup();
  return 0;
}

If client code is needed - I can supply! Thanks!

regards.

use threds. Look up the CreateThread function in MSDN. Call accept in a loop. Each time you accept a new connection spawn a new thread with CreateThread and pass the new socket as the paramater.

Look up the CreateThread function in MSDN

He shouldn't use CreateThread() since he is linking to the crt library. Use _beginthread() or _beginthreadex() instead.

Another option is to use asynchronous sockets. This allows you to use a multiple socket paradigm without creating multiple threads. Read up on WSAAsyncSelect for more information on this.