TCPServerResenje1

#define _WINSOCK_DEPRECATED_NO_WARNINGS
#define WIN32_LEAN_AND_MEAN

#include <windows.h>
#include <winsock2.h>
#include <ws2tcpip.h>
#include <stdlib.h>
#include <stdio.h>
#include "conio.h"

#pragma comment (lib, "Ws2_32.lib")
#pragma comment (lib, "Mswsock.lib")
#pragma comment (lib, "AdvApi32.lib")

#define SERVER_PORT 27016
#define BUFFER_SIZE 256

// TCP server that use blocking sockets
int main()
{
    // Socket used for listening for new clients
    SOCKET listenSocket = INVALID_SOCKET;

    // Socket used for communication with clients
    SOCKET acceptedSocket1 = INVALID_SOCKET;
    SOCKET acceptedSocket2 = INVALID_SOCKET;

    // Variable used to store function return value
    int iResult;
    bool first, second;
    bool quit1, quit2;

    int words1, words2;
    int length1, length2;


    // Buffer used for storing incoming data
    char dataBuffer1[BUFFER_SIZE];
    char dataBuffer2[BUFFER_SIZE];

    // WSADATA data structure that is to receive details of the Windows Sockets implementation
    WSADATA wsaData;

    // Initialize windows sockets library for this process
    if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0)
    {
        printf("WSAStartup failed with error: %d\n", WSAGetLastError());
        return 1;
    }


    // Initialize serverAddress structure used by bind
    sockaddr_in serverAddress;
    memset((char*)&serverAddress, 0, sizeof(serverAddress));
    serverAddress.sin_family = AF_INET;             // IPv4 address family
    serverAddress.sin_addr.s_addr = INADDR_ANY;     // Use all available addresses
    serverAddress.sin_port = htons(SERVER_PORT);    // Use specific port


    // Create a SOCKET for connecting to server
    listenSocket = socket(AF_INET,      // IPv4 address family
        SOCK_STREAM,  // Stream socket
        IPPROTO_TCP); // TCP protocol

// Check if socket is successfully created
    if (listenSocket == INVALID_SOCKET)
    {
        printf("socket failed with error: %ld\n", WSAGetLastError());
        WSACleanup();
        return 1;
    }

    // Setup the TCP listening socket - bind port number and local address to socket
    iResult = bind(listenSocket, (struct sockaddr*)&serverAddress, sizeof(serverAddress));

    // Check if socket is successfully binded to address and port from sockaddr_in structure
    if (iResult == SOCKET_ERROR)
    {
        printf("bind failed with error: %d\n", WSAGetLastError());
        closesocket(listenSocket);
        WSACleanup();
        return 1;
    }

    // Set listenSocket in listening mode
    iResult = listen(listenSocket, SOMAXCONN);
    if (iResult == SOCKET_ERROR)
    {
        printf("listen failed with error: %d\n", WSAGetLastError());
        closesocket(listenSocket);
        WSACleanup();
        return 1;
    }

    printf("Server socket is set to listening mode. Waiting for new connection requests.\n");

    do
    {
        // Struct for information about connected client
        sockaddr_in clientAddr;

        int clientAddrSize = sizeof(struct sockaddr_in);

        // Accept new connections from clients
        acceptedSocket1 = accept(listenSocket, (struct sockaddr*)&clientAddr, &clientAddrSize);

        // Check if accepted socket is valid
        if (acceptedSocket1 == INVALID_SOCKET)
        {
            printf("accept failed with error: %d\n", WSAGetLastError());
            closesocket(listenSocket);
            WSACleanup();
            return 1;
        }

        printf("\nFirst client request accepted. Client address: %s : %d\n", inet_ntoa(clientAddr.sin_addr), ntohs(clientAddr.sin_port));

        //accept the second client
        acceptedSocket2 = accept(listenSocket, (struct sockaddr*)&clientAddr, &clientAddrSize);

        // Check if accepted socket is valid
        if (acceptedSocket2 == INVALID_SOCKET)
        {
            printf("accept failed with error: %d\n", WSAGetLastError());
            closesocket(listenSocket);
            closesocket(acceptedSocket1);
            WSACleanup();
            return 1;
        }

        printf("\nSecond client request accepted. Client address: %s : %d\n", inet_ntoa(clientAddr.sin_addr), ntohs(clientAddr.sin_port));

        printf("Enter a letter on which play starts: ");
        char slovo;
        scanf_s(" %c", &slovo);
        getchar();

        sprintf_s(dataBuffer1, "Pocinje igra na slovo na slovo %c. Posaljite vasu rec!\n", slovo);
        sprintf_s(dataBuffer2, "Pocinje igra na slovo na slovo %c. Posaljite vasu rec!\n", slovo);

        words1 = words2 = 0;    //count number of correct words of first and second player
        length1 = length2 = 0;  //total length of correct words of first and second player
        quit1 = quit2 = false;  //indicates if player quits the game
        bool end = false;     // indicator of the game end

        do
        {
            // Send message to clients using connected socket
            iResult = send(acceptedSocket1, dataBuffer1, (int)strlen(dataBuffer1), 0);

            // Check result of send function
            if (iResult == SOCKET_ERROR)
            {
                printf("send failed with error: %d\n", WSAGetLastError());
                shutdown(acceptedSocket1, SD_BOTH);
                shutdown(acceptedSocket2, SD_BOTH);
                closesocket(acceptedSocket1);
                closesocket(acceptedSocket2);
                break;
            }

            iResult = send(acceptedSocket2, dataBuffer2, (int)strlen(dataBuffer2), 0);

            // Check result of send function
            if (iResult == SOCKET_ERROR)
            {
                printf("send failed with error: %d\n", WSAGetLastError());
                shutdown(acceptedSocket1, SD_BOTH);
                shutdown(acceptedSocket2, SD_BOTH);
                closesocket(acceptedSocket1);
                closesocket(acceptedSocket2);
                break;
            }

            //if the play between two players ends
            if (end)
                break;


            // Receive data from first client
            iResult = recv(acceptedSocket1, dataBuffer1, BUFFER_SIZE, 0);

            if (iResult > 0)    // Check if message is successfully received
            {
                dataBuffer1[iResult] = '\0';

                // Log message text
                printf("Client 1 sent: %s.\n", dataBuffer1);

                if (!strcmp(dataBuffer1, "Kraj"))  //first player is quitting the game
                {
                    quit1 = true;
                    first = false;
                }
                else
                {
                    //check if player sent word on selected letter.
                    // Change letter in upper-case to include both small and big letters
                    if (toupper(dataBuffer1[0]) == toupper(slovo))
                    {
                        printf("Correct word! \n");
                        first = true;
                        words1++;
                        length1 += strlen(dataBuffer1);
                    }
                    else
                    {
                        printf("Incorrect word! \n");
                        first = false;
                    }
                }

            }
            else if (iResult == 0)  // Check if shutdown command is received
            {
                // Connection was closed successfully
                printf("Connection with first client closed.\n");
                shutdown(acceptedSocket2, SD_BOTH);
                closesocket(acceptedSocket1);
                closesocket(acceptedSocket2);
                break;
            }
            else    // There was an error during recv
            {

                printf("recv failed with error: %d\n", WSAGetLastError());
                shutdown(acceptedSocket1, SD_BOTH);
                shutdown(acceptedSocket2, SD_BOTH);
                closesocket(acceptedSocket1);
                closesocket(acceptedSocket2);
                break;
            }


            // Receive data from second client
            iResult = recv(acceptedSocket2, dataBuffer2, BUFFER_SIZE, 0);

            if (iResult > 0)    // Check if message is successfully received
            {
                dataBuffer2[iResult] = '\0';

                // Log message text
                printf("Client 2 sent: %s.\n", dataBuffer2);

                if (!strcmp(dataBuffer2, "Kraj"))    //second player is quitting
                {
                    quit2 = true;
                    second = false;

                }
                else
                {
                    //check if player sent word on selected letter
                    // Change letter in upper-case to include both small and big letters
                    if (toupper(dataBuffer2[0]) == toupper(slovo))
                    {
                        printf("Correct word! \n");
                        second = true;
                        words2++;
                        length2 += strlen(dataBuffer2);
                    }
                    else
                    {
                        printf("Incorrect word! \n");
                        second = false;
                    }
                }

            }
            else if (iResult == 0)  // Check if shutdown command is received
            {
                // Connection was closed successfully
                printf("Connection with client closed.\n");
                shutdown(acceptedSocket1, SD_BOTH);
                closesocket(acceptedSocket1);
                closesocket(acceptedSocket2);
                break;
            }
            else    // There was an error during recv
            {

                printf("recv failed with error: %d\n", WSAGetLastError());
                shutdown(acceptedSocket1, SD_BOTH);
                shutdown(acceptedSocket2, SD_BOTH);
                closesocket(acceptedSocket1);
                closesocket(acceptedSocket2);
                break;
            }

            // the play continues if both clients have good words or both mistake
            if (first == second)
            {
                strcpy_s(dataBuffer1, "Please send next word on chosen letter.");
                strcpy_s (dataBuffer2, "Please send next word on chosen letter.");
            }
            //one has mistaken other has right word (he is the winner)
            else
            {
                //first player wins
                if (first)
                {
                    sprintf_s(dataBuffer1, "Prvi igrac je poslao %d ispravnih reci, drugi igrac je poslao %d ispravnih reci. Vi ste POBEDILI!\n", words1, words2);
                    sprintf_s(dataBuffer2, "Prvi igrac je poslao %d ispravnih reci, drugi igrac je poslao %d ispravnih reci. Vi ste IZGUBILI!\n", words1, words2);
                    end = true;
                }
                //second player wins
                if (second)
                {
                    sprintf_s(dataBuffer1, "Prvi igrac je poslao %d ispravnih reci, drugi igrac je poslao %d ispravnih reci. Vi ste IZGUBILI!\n", words1, words2);
                    sprintf_s(dataBuffer2, "Prvi igrac je poslao %d ispravnih reci, drugi igrac je poslao %d ispravnih reci. Vi ste POBEDILI!\n", words1, words2);
                    end = true;
                }

            }
            // if both players quit at the same time
            if (quit1 && quit2)
            {
                if (length1 > length2)
                {
                    sprintf_s(dataBuffer1, "Prvi igrac je poslao %d ispravnih reci, drugi igrac je poslao %d ispravnih reci. Ukupna duzina vasih reci je veca. Vi ste POBEDILI!\n", words1, words2);
                    sprintf_s(dataBuffer2, "Prvi igrac je poslao %d ispravnih reci, drugi igrac je poslao %d ispravnih reci. Ukupna duzina vasih reci je kraca.Vi ste IZGUBILI!\n", words1, words2);
                    end = true;
                }
                else
                {
                    sprintf_s(dataBuffer1, "Prvi igrac je poslao %d ispravnih reci, drugi igrac je poslao %d ispravnih reci.Ukupna duzina vasih reci je kraca. Vi ste IZGUBILI!\n", words1, words2);
                    sprintf_s(dataBuffer2, "Prvi igrac je poslao %d ispravnih reci, drugi igrac je poslao %d ispravnih reci.Ukupna duzina vasih reci je veca. Vi ste POBEDILI!\n", words1, words2);
                    end = true;
                }
            }


        } while (true);


    } while (true);

    // Shutdown the connection since we're done
    iResult = shutdown(acceptedSocket1, SD_BOTH);

    // Check if connection is succesfully shut down.
    if (iResult == SOCKET_ERROR)
    {
        printf("shutdown failed with error: %d\n", WSAGetLastError());
        closesocket(acceptedSocket1);
        closesocket(acceptedSocket2);
        WSACleanup();
        return 1;
    }

    // Shutdown the connection since we're done
    iResult = shutdown(acceptedSocket2, SD_BOTH);

    // Check if connection is succesfully shut down.
    if (iResult == SOCKET_ERROR)
    {
        printf("shutdown failed with error: %d\n", WSAGetLastError());
        closesocket(acceptedSocket1);
        closesocket(acceptedSocket2);
        WSACleanup();
        return 1;
    }
    //Close listen and accepted sockets
    closesocket(listenSocket);
    closesocket(acceptedSocket1);
    closesocket(acceptedSocket2);

    // Deinitialize WSA library
    WSACleanup();

    return 0;
}