Blocking socket programming

blocking.cc

int main() {
  int socketFd = socket(AF_INET, SOCK_STREAM, 0);
  assert(socketFd != 0);

  sockaddr_in addr{};
  socklen_t addrLen = sizeof(addr);

  int opt = 1;
  assert(setsockopt(socketFd, SOL_SOCKET, SO_REUSEADDR | SO_REUSEPORT, &opt, sizeof(opt)) == 0);

  addr.sin_family = AF_INET;
  addr.sin_addr.s_addr = INADDR_ANY;
  addr.sin_port = htons(PORT);

  assert(bind(socketFd, (sockaddr *) &addr, addrLen) >= 0);
  assert(listen(socketFd, 3) >= 0);
  const int acceptFd = accept(socketFd, (sockaddr *) &addr, &addrLen);
  assert(acceptFd >= 0);

  while (true) {
    char buffer[BUFFER_SIZE];
    const int len = recv(acceptFd, buffer, sizeof buffer, 0);
    if (len > 0) {
      const long t = chrono::duration_cast<chrono::seconds>(chrono::system_clock::now().time_since_epoch()).count();
      printf("[%d] %.*s\n", t, len, buffer);
    } else if (len == 0) {
      cout << "Disconnected." << endl;
      break;
    } else {
      if (errno == EAGAIN || errno == EWOULDBLOCK) {
        cout << "Waiting for message..." << endl;
        std::this_thread::sleep_for(chrono::seconds (1));
        continue;
      }
      assert(false);
    }
  }

  close(acceptFd);
  close(socketFd);

  return 0;
}