Untitled

//server.c


int main() {

    time(&start);
    // Call a function to handle agent login
    pid_t child_pid;

    // Declare variables for socket creation and binding
    int i = 1;
    struct sockaddr_in address;
    int adlength,valread;
    
    // Create a socket using socket() system call
    int sock = create_socket();

    if (sock == -1) {
        // If there was an error creating the socket, print an error message
        printf("\n*************Socket Error!*******************\n");
    }

    // Bind server’s address and port using bind() system call
    connect__data result = bind_port(sock);

    // Get the address and address length from the connect_data struct
    address = result.adres;
    adlength = result.address_length;

    // Get the bind result from the connect_data struct
    int bind_res = result.bind_result;

    // Convert the socket into a listening socket using listen() system call
    if (listen(sock, MAX_CLIENTS) < 0) {
        // If there was an error setting the socket to listen, print an error message
        printf("Listen Error!\n");
        return 1;
    } 

    // Accept client connections using accept() system call
    printf("\nServer is listening on port %d....\n\n", PORT);

    while (1) {

       int new_socket = accept(sock, (struct sockaddr*)&address, (socklen_t*)&adlength);
       printf("Client-%d connected\n",i);
       
        if (new_socket < 0) {
            // If there was an error accepting the client connection, print an error message
            printf("Accept Error!\n");
            return 1;
        } 

        if ((child_pid == fork()) == 0) {

            close(sock);

            char buffer_array[1024];
            char result_array[1024];
            double result_num;

            valread = read(new_socket, buffer_array, strlen(buffer_array));

            buffer_array[strlen(buffer_array)-1] = '\0';

            printf("Received data = '%s' from [ Client-%d ]\n", buffer_array, i);

            result_num = compute_postfix_expression(buffer_array);

            sprintf(result_array, "%.1f", result_num);   

            send(new_socket, result_array, strlen(result_array), 0);

            FILE* file = fopen("server_records.txt", "a");

            if (file != NULL) {

                time(&current);
                double time_diff = difftime(current, start);
                fprintf(file, "[ Client ID: '%d' ], [ Query: '%s' ]. [Answer: '%s' ], [Time Elapsed(sec): '%.0f'] \n\n", i, buffer_array, result_array, time_diff);
                fclose(file);
            } 

            close(new_socket);
            exit(0);         

        }
        i++;
        close(new_socket);

    }

    return 0;
}