Function cancel_all

src/test/common/test_ceph_timer.cc:103–116

template<typename TC>
void cancel_all()
{
  ceph::timer<TC> timer;
  static constexpr auto MAX_FUTURES = 5;
  std::vector<std::future<void>> futures;
  for (auto i = 0; i < MAX_FUTURES; ++i) {
    std::promise<void> p;
    futures.push_back(p.get_future());
    timer.add_event(100s + i*1s, Destructo(std::move(p)));
  }
  timer.cancel_all_events();
  for (auto& f : futures)
    f.get();
}

template<typename TC>
void cancellation()