C++_TCP

// Получение IP адресов IPv4 & IPv6 по имени хоста.
#include <winsock2.h>
#include <stdio.h>
#include <ws2tcpip.h>
#include <iostream>
#include <thread>
#pragma comment(lib,"Ws2_32.lib")

using namespace std;

void getIPbyHostname();
void connect();
void listen();
void printIPnv(struct addrinfo* p);
void printOpenPorts();

bool isListen = false;

int main() {

    void (*pf)() = &listen;
    //getIPbyHostname();
    std::thread t(pf);
    t.detach();
    while (isListen == false) this_thread::sleep_for(std::chrono::seconds(1));
    connect();


    system("pause");
    return 0;
}

void getIPbyHostname()
{
    WSADATA wsaData;
    if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0)
    {
        cout << "WSAStartup Failed.";
    }
    else
    {
        string str_host;

        cout << "Enter hostname" << endl;
        cin >> str_host;

        const char* host = str_host.c_str();

        struct addrinfo hints, * res, * p;
        int status;
        char ipstr[INET6_ADDRSTRLEN];

        memset(&hints, 0, sizeof hints);
        hints.ai_family = AF_UNSPEC;
        hints.ai_socktype = SOCK_STREAM;

        if ((status = getaddrinfo(host, NULL, &hints, &res)) != 0) {
            cout << "error in status";
            return;
        }

        for (p = res; p != NULL; p = p->ai_next) {
            void* addr;
            char* ipver;

            printIPnv(p);
        }

        freeaddrinfo(res);
        WSACleanup();
    }
}

void connect()
{
    WSADATA wsaData;
    if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0)
    {
        cout << "WSAStartup Failed.";
    }
    else
    {
        string host, port;

        cout << "Enter hostname" << endl;
        cin >> host;
        cout << "Enter port" << endl;
        cin >> port;

        struct addrinfo hints, * res;
        int sockfd;

        memset(&hints, 0, sizeof hints);
        hints.ai_family = AF_UNSPEC;
        hints.ai_socktype = SOCK_STREAM;

        getaddrinfo(host.c_str(), port.c_str(), &hints, &res);

        sockfd = socket(res->ai_family, res->ai_socktype, res->ai_protocol);

        if (connect(sockfd, res->ai_addr, res->ai_addrlen) != -1)
            cout << "Successfully connect" << endl;
        else
            cout << "Error connect, code: " << errno << endl;

        freeaddrinfo(res);
        WSACleanup();

        //if (bind(sockfd, res->ai_addr, res->ai_addrlen) == -1)
        //  cout << "Binding error, code: " << errno << endl;
    }


}

void listen()
{
    WSADATA wsaData;
    if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0)
    {
        cout << "WSAStartup Failed.";
    }
    else
    {
        struct sockaddr_storage their_addr;
        socklen_t addr_size;
        string port, backlog; //backlog - очередь ожидающих подключений

        cout << "Enter port" << endl;
        cin >> port;
        cout << "Enter backlog" << endl;
        cin >> backlog;

        struct addrinfo hints, * res;
        int sockfd, new_fd;

        memset(&hints, 0, sizeof hints);
        hints.ai_family = AF_UNSPEC;
        hints.ai_socktype = SOCK_STREAM;

        getaddrinfo("192.168.1.200", port.c_str(), &hints, &res);

        sockfd = socket(res->ai_family, res->ai_socktype, res->ai_protocol);

        if (bind(sockfd, res->ai_addr, res->ai_addrlen) != -1)
            cout << "Success binding" << endl;
        else
            cout << "Binding error, code: " << errno << endl;

        if (listen(sockfd, atoi(backlog.c_str())) != -1) {
            cout << "Success listening" << endl;
            isListen = true;
        }
        else
            cout << "Error listening, code: " << errno << endl;

        printIPnv(res);

        addr_size = sizeof their_addr;
        new_fd = accept(sockfd, (struct sockaddr*) & their_addr, &addr_size);

        freeaddrinfo(res);
        WSACleanup();
    }
}

void printIPnv(struct addrinfo *p)
{
    void* addr;
    char* ipver;
    char ipstr[INET6_ADDRSTRLEN];

    //IPv4
    if (p->ai_family == AF_INET) {
        struct sockaddr_in* ipv4 = (struct sockaddr_in*)p->ai_addr;
        addr = &(ipv4->sin_addr);
        ipver = (char*)"IPv4";
    }
    //IPv6
    else {
        struct sockaddr_in6* ipv6 = (struct sockaddr_in6*)p->ai_addr;
        addr = &(ipv6->sin6_addr);
        ipver = (char*)"IPv6";
    }

    inet_ntop(p->ai_family, addr, ipstr, sizeof ipstr);
    cout << ipver << ": " << ipstr << "\n";
}

void printOpenPorts()
{
    WSADATA wsaData;
    if (WSAStartup(MAKEWORD(2, 2), &wsaData) != 0)
    {
        cout << "WSAStartup Failed.";
    }
    else
    {
        string str_host;

        cout << "Enter hostname" << endl;
        str_host = "localhost";

        struct addrinfo hints, * res;
        int sock;

        memset(&hints, 0, sizeof hints);
        hints.ai_family = AF_UNSPEC;
        hints.ai_socktype = SOCK_STREAM;

        getaddrinfo(str_host.c_str(), "5000", &hints, &res);

        sock = socket(res->ai_family, res->ai_socktype, res->ai_protocol);
        if (connect(sock, res->ai_addr, res->ai_addrlen) != -1)
            cout << "Port 0 is open" << endl;
    }
}