Issue with basic server/client code - c++

Question

I'm attempting to teach myself some networking programming in C++, but I'm running into some core issues that I can't seem to solve.
I have two programs that are in the same VS project- a client and a server. They don't exchange information, they simply connect and tell me when the connection is established. Here is the client file-
SERVER.CPP
#include "stdafx.h"
using namespace std;
int main()
{
//setting up WSA
WSADATA wsaData;
int WSAcheck = WSAStartup(MAKEWORD(2, 2), &wsaData);
//checking WSA
if (WSAcheck != 0)
{
printf("WSA couldn't start correctly\n");
pause();
exit;
}
//setting up the socket
SOCKET serversock = socket(AF_INET, SOCK_STREAM, 0);
//checking socket's validity
if (serversock == INVALID_SOCKET)
{
printf("Socket isn't valid: %d\n", WSAGetLastError());
pause();
exit;
}
//setting up the sockaddr_in for bind()
sockaddr_in server_sockaddr;
server_sockaddr.sin_family = AF_INET;
server_sockaddr.sin_addr.s_addr = INADDR_ANY;
server_sockaddr.sin_port = htons(25565);
//binding the socket.
int bindcheck = bind(serversock, (struct sockaddr *)&server_sockaddr, sizeof(server_sockaddr));
//checking to see if the bind worked, and calling the error if it doesn't
if (bindcheck != 0)
{
printf("Bind failed: %d\n", WSAGetLastError());
pause();
exit;
}
//setting the socket to listen
int listencheck = listen(serversock, 10);
//checking to make sure the listen command was successful
if (listencheck != 0)
{
printf("Listen failed: %d\n", WSAGetLastError());
pause();
exit;
}
//telling that the socket is being set to listen
printf("Socket is ready to accept connections\n");
//accepting any incoming connections
SOCKET clientsocket = accept(serversock, NULL, NULL);
//checking the socket
if (clientsocket == INVALID_SOCKET)
{
printf("Connecting socket isn't valid or has timed out: %d\n", WSAGetLastError());
pause();
exit;
}
//ending the program
printf("fin\n");
pause();
}
CLIENT.CPP
#include "stdafx.h"
using namespace std;
int main()
{
//setting up WSA
WSADATA wsaData;
int WSAcheck = WSAStartup(MAKEWORD(2, 2), &wsaData);
//checking WSA
if (WSAcheck != 0)
{
printf("WSA couldn't start correctly\n");
pause();
exit;
}
//setting up the socket
SOCKET clientsock = socket(AF_INET, SOCK_STREAM, 0);
//checking socket's validity
if (clientsock == INVALID_SOCKET)
{
printf("Socket isn't valid: %d\n", WSAGetLastError());
pause();
exit;
}
//setting up the struct with the connection info
sockaddr_in serverinfo;
serverinfo.sin_family = AF_INET;
serverinfo.sin_addr.s_addr = INADDR_ANY;
serverinfo.sin_port = htons(25565);
//connecting
printf("Trying to connect\n");
connect(clientsock, (SOCKADDR *)&serverinfo, sizeof(serverinfo));
printf("Passed the connect function\n");
pause();
}
STDAFX.H
// stdafx.h : include file for standard system include files,
// or project specific include files that are used frequently, but
// are changed infrequently
#pragma once
#include "targetver.h"
#include <stdio.h>
#include <tchar.h>
#include <winsock2.h>
#include <Ws2tcpip.h>
#include <Inaddr.h>
#include <string.h>
#include <io.h>
#include <Windef.h>
#include <Ws2tcpip.h>
#include <WinNT.h>
#include <Windows.h>
#include <tchar.h>
void pause(void); //defined in stdafx.cpp
pause is defined as getchar(), to break the code to see what is going on.
The output for the client is -
Trying to connect
Passed the connect function
regardless of whether the server process is running.
The output for the server is
The socket is ready to accept connections
regardless of what I test, I cannot get it to pass that.
What am I doing wrong?

Answer 1

You have an error in the client. This is bad:
serverinfo.sin_addr.s_addr = INADDR_ANY;
Instead of INADDR_ANY you have to write the server IP address, maybe 127.0.0.1 if they run in the same server, in binary format.
Use this function to convert from text IP address to binary IP address:
INT WSAAPI InetPton(
_In_ INT Family,
_In_ PCTSTR pszAddrString,
_Out_ PVOID pAddrBuf
);
https://msdn.microsoft.com/en-us/library/windows/desktop/cc805844(v=vs.85).aspx
The code would be:
if(InetPton(AF_INET, "192.168.0.1", (void*)&serverinfo.sin_addr.s_addr) <= 0)
{
//error
}