Function DoDial

engine/dlib/src/dlib/connection_pool.cpp:445–551

    }

    Result DoDial(HPool pool, const char* host, uint16_t port, bool ssl, int timeout, int* cancelflag, HConnection* connection, dmSocket::Result* sock_res, bool ipv4, bool ipv6)
    {
        if (!pool->m_AllowNewConnections) {
            return RESULT_SHUT_DOWN;
        }

        // This function would previously not specify ipv4 and/or ipv6 when calling GetHostByName.
        // GetHostByName would then assume both ipv4 and ipv6 and always prefer and return an ipv4
        // address.
        // Connecting to the returned address would fail when on an ipv6 network.
        // This is why when calling DoDial we now have the ability to specify ipv4 and/or ipv6 so
        // that the caller can try to connect first to ipv4 and then to ipv6 if ipv4 failed.
        dmSocket::Address address;

        uint64_t dial_started = dmTime::GetMonotonicTime();
        bool gethost_did_succeed = dmSocket::GetHostByNameT(host, &address, timeout, cancelflag, ipv4, ipv6) == dmSocket::RESULT_OK;
        if (timeout > 0)
        {
            timeout = timeout - (int)(dmTime::GetMonotonicTime() - dial_started);
            if (timeout <= 0)
            {
                return RESULT_SOCKET_ERROR;
            }
        }

        dmhash_t conn_id = CalculateConnectionID(address, port, ssl);

        Connection* c = 0;
        uint32_t index;

        if (gethost_did_succeed) {
            DM_MUTEX_SCOPED_LOCK(pool->m_Mutex);

            PurgeExpired(pool);

            if (!pool->m_AllowNewConnections) {
                *sock_res = dmSocket::RESULT_CONNABORTED;
                return RESULT_SHUT_DOWN;
            }

            if (FindConnection(pool, conn_id, address, port, ssl, connection)) {
                return RESULT_OK;
            }

            if (!FindSlot(pool, &index, &c)) {
                return RESULT_OUT_OF_RESOURCES;
            }
            c->m_State = STATE_INUSE; // The connection might fail, but we need to reserve this in the meantime

        } else {
            *sock_res = dmSocket::RESULT_HOST_NOT_FOUND; // Only error that dmSocket::getHostByName returns
            return RESULT_SOCKET_ERROR;
        }

        dmSocket::Socket socket = dmSocket::INVALID_SOCKET_HANDLE;
        dmSSLSocket::Socket sslsocket = dmSSLSocket::INVALID_SOCKET_HANDLE;

        Result r = Connect(pool, c, host, address, port, timeout, &socket, sock_res);