message: network::tcp::server::ConnectionProvider: Fix code review comments
diff: @@ -186,7 +186,7 @@ oatpp::v_io_handle ConnectionProvider::instantiateServer(){
  int no = 0;
  - if (hints.ai_family == AF_UNSPEC || hints.ai_family == Address::IP_6) {
  + if (hints.ai_family == AF_UNSPEC || hints.ai_family == AF_INET6) {
  if (setsockopt(serverHandle, IPPROTO_IPV6, IPV6_V6ONLY, (char*)&no, sizeof( int ) ) != 0 ) {
  OATPP_LOGW("[oatpp::network::tcp::server::ConnectionProvider::instantiateServer()]",
  "Warning. Failed to set %s for accepting socket: %s", "IPV6_V6ONLY",
  @@ -317,7 +317,7 @@ oatpp::v_io_handle ConnectionProvider::instantiateServer(){
  bool ConnectionProvider::prepareConnectionHandle(oatpp::v_io_handle handle) {
  - if (handle < 0) {
  + if (!oatpp::isValidIOHandle(handle)) {
  v_int32 error = errno;
  if(error == EAGAIN || error == EWOULDBLOCK){
  return false;
  @@ -345,10 +345,6 @@ provider::ResourceHandle<data::stream::IOStream> ConnectionProvider::getDefaultC
  oatpp::v_io_handle handle = accept(m_serverHandle, nullptr, nullptr);
  - if(!oatpp::isValidIOHandle(handle)) {
  - return nullptr;
  - }
  -
  if(prepareConnectionHandle(handle)) {
  return provider::ResourceHandle<data::stream::IOStream>(
  std::make_shared<Connection>(handle),
  @@ -419,6 +415,8 @@ provider::ResourceHandle<data::stream::IOStream> ConnectionProvider::getExtended
  provider::ResourceHandle<oatpp::data::stream::IOStream> ConnectionProvider::get() {
  + while(!m_closed) {
  +
  fd_set set;
  struct timeval timeout;
  FD_ZERO(&set);
  @@ -427,8 +425,6 @@ provider::ResourceHandle<oatpp::data::stream::IOStream> ConnectionProvider::get(
  timeout.tv_sec = 1;
  timeout.tv_usec = 0;
  - while(!m_closed) {
  -
  auto res = select(int(m_serverHandle + 1), &set, nullptr, nullptr, &timeout);
  if (res >= 0) {
  