Method GetExploratoryNonFloodfill

libi2pd/NetDb.cpp:1330–1374

	}

	std::vector<IdentHash> NetDb::GetExploratoryNonFloodfill (const IdentHash& destination,
		size_t num, const std::unordered_set<IdentHash>& excluded)
	{
		std::vector<IdentHash> ret;
		if (!num || m_RouterInfos.empty ()) return ret; // empty list
		auto ts = i2p::util::GetMonotonicSeconds ();
		if (ts > m_LastExploratorySelectionUpdateTime +	NETDB_EXPLORATORY_SELECTION_UPDATE_INTERVAL)
		{
			// update selection
			m_ExploratorySelection.clear ();
			std::vector<std::shared_ptr<const RouterInfo> > eligible;
			eligible.reserve (m_RouterInfos.size ());
			{
				// collect eligible from current netdb
				bool checkIsReal = i2p::tunnel::tunnels.GetPreciseTunnelCreationSuccessRate () < NETDB_TUNNEL_CREATION_RATE_THRESHOLD; // too low rate
				std::lock_guard<std::mutex> l(m_RouterInfosMutex);
				for (const auto& it: m_RouterInfos)
					if (!it.second->IsDeclaredFloodfill () &&
					 	(!checkIsReal || (it.second->HasProfile () && it.second->GetProfile ()->IsReal ())))
							eligible.push_back (it.second);
			}
			if (eligible.size () > NETDB_MAX_EXPLORATORY_SELECTION_SIZE)
			{
				 std::sample (eligible.begin(), eligible.end(), std::back_inserter(m_ExploratorySelection),
				 	NETDB_MAX_EXPLORATORY_SELECTION_SIZE, m_Rng);
			}
			else
				std::swap (m_ExploratorySelection, eligible);
			m_LastExploratorySelectionUpdateTime = ts;
		}

		// sort by distance
		IdentHash destKey = CreateRoutingKey (destination);
		std::map<XORMetric, std::shared_ptr<const RouterInfo> > sorted;
		for (const auto& it: m_ExploratorySelection)
			if (!excluded.count (it->GetIdentHash ()))
				sorted.emplace (destKey ^ it->GetIdentHash (), it);
		// return first num closest routers
		for (const auto& it: sorted)
		{
			ret.push_back (it.second->GetIdentHash ());
			if (ret.size () >= num) break;
		}
		return ret;
	}

	void NetDb::ManageRouterInfos ()
	{