export number of known torrent peers (list_peers) to the dht tracker resource and use it

as estimative to the number of followers. at least we get the number of *online* followers.

libtorrent/include/libtorrent/kademlia/dht_get.hpp

@@ -98,6 +98,8 @@ private:
 	bool m_done:1;
 	bool m_got_data:1;
 	bool m_justToken:1;
+
+	friend class dht_get_observer;
 };
 
 class dht_get_observer : public observer

libtorrent/include/libtorrent/kademlia/dht_tracker.hpp

@@ -93,7 +93,7 @@ namespace libtorrent { namespace dht
 		entry state() const;
 
 		void announce(std::string const& trackerName, sha1_hash const& ih
-			, address addr, int listen_port, bool seed, bool myself
+			, address addr, int listen_port, bool seed, bool myself, int list_peers
 			, boost::function<void(std::vector<tcp::endpoint> const&)> f);
 
 		void putData(std::string const &username, std::string const &resource, bool multi,

libtorrent/include/libtorrent/kademlia/node.hpp

@@ -112,6 +112,7 @@ struct torrent_entry
 {
 	std::string name;
 	std::set<peer_entry> peers;
+	int list_peers; // number of known peers (copied from torrent status)
 };
 
 struct dht_storage_item
@@ -215,7 +216,7 @@ public:
 #endif
 
 	void announce(std::string const& trackerName, sha1_hash const& info_hash
-		, address addr, int listen_port, bool seed, bool myself
+		, address addr, int listen_port, bool seed, bool myself, int list_peers
 		, boost::function<void(std::vector<tcp::endpoint> const&)> f);
 
 	void putData(std::string const &username, std::string const &resource, bool multi,
@@ -268,7 +269,7 @@ protected:
 
 	void lookup_peers(sha1_hash const& info_hash, int prefix, entry& reply
 		, bool noseed, bool scrape) const;
-	void add_peer(std::string const& name, sha1_hash const& info_hash, address addr, int port, bool seed);
+	void add_peer(std::string const& name, sha1_hash const& info_hash, address addr, int port, bool seed, int list_peers);
 
 	dht_settings const& m_settings;
 	

libtorrent/src/kademlia/dht_get.cpp

@@ -127,6 +127,32 @@ void dht_get_observer::reply(msg const& m)
 		}
 	//printf("dht_get::reply from %s:%d with %d entries\n", m.addr.address().to_string().c_str(), m.addr.port(), values_list.size());
 		static_cast<dht_get*>(m_algorithm.get())->got_data(values_list);
+	} else {
+		// special case for trackers (non-signed content)
+		// pretend it is a normal dht resource to the caller
+		dht_get *dget( static_cast<dht_get*>(m_algorithm.get()) );
+		if( dget->m_targetResource == "tracker" && dget->m_multi ) {
+			int followers = r->dict_find_int_value("followers");
+			if( followers ) {
+				entry::dictionary_type v;
+				v["followers"] = followers;
+
+				entry::dictionary_type target;
+				target["n"] = dget->m_targetUser;
+				target["r"] = dget->m_targetResource;
+				target["t"] = dget->m_multi ? "m" : "s";
+
+				entry::dictionary_type p;
+				p["target"] = target;
+				p["v"] = v;
+
+				entry::dictionary_type e;
+				e["p"] = p;
+				entry::list_type values_list;
+				values_list.push_back(e);
+				dget->got_data(values_list);
+			}
+		}
 	}
 
 	// look for nodes

libtorrent/src/kademlia/dht_tracker.cpp

@@ -427,10 +427,10 @@ namespace libtorrent { namespace dht
 	}
 
 	void dht_tracker::announce(std::string const& trackerName, sha1_hash const& ih
-		, address addr, int listen_port, bool seed, bool myself
+		, address addr, int listen_port, bool seed, bool myself, int list_peers
 		, boost::function<void(std::vector<tcp::endpoint> const&)> f)
 	{
-		m_dht.announce(trackerName, ih, addr, listen_port, seed, myself, f);
+		m_dht.announce(trackerName, ih, addr, listen_port, seed, myself, list_peers, f);
 	}
 
 	void dht_tracker::putData(std::string const &username, std::string const &resource, bool multi,

libtorrent/src/kademlia/node.cpp

@@ -400,7 +400,7 @@ void node_impl::add_node(udp::endpoint node)
 	m_rpc.invoke(e, node, o);
 }
 
-void node_impl::announce(std::string const& trackerName, sha1_hash const& info_hash, address addr, int listen_port, bool seed, bool myself
+void node_impl::announce(std::string const& trackerName, sha1_hash const& info_hash, address addr, int listen_port, bool seed, bool myself, int list_peers
 	, boost::function<void(std::vector<tcp::endpoint> const&)> f)
 {
 #ifdef TORRENT_DHT_VERBOSE_LOGGING
@@ -410,7 +410,7 @@ void node_impl::announce(std::string const& trackerName, sha1_hash const& info_h
 
 	// [MF] is_unspecified() is not always available. never mind.
 	//if( !addr.is_unspecified() ) {
-		add_peer( trackerName, info_hash, addr, listen_port, seed );
+		add_peer( trackerName, info_hash, addr, listen_port, seed, list_peers );
 	//}
 
 	// do not announce other peers, just add them to our local m_map.
@@ -762,6 +762,7 @@ void node_impl::lookup_peers(sha1_hash const& info_hash, int prefix, entry& repl
 	torrent_entry const& v = i->second;
 
 	if (!v.name.empty()) reply["n"] = v.name;
+	reply["followers"] = v.list_peers;
 
 	if (scrape)
 	{
@@ -803,7 +804,7 @@ void node_impl::lookup_peers(sha1_hash const& info_hash, int prefix, entry& repl
 	return;
 }
 
-void node_impl::add_peer(std::string const &name, sha1_hash const& info_hash, address addr, int port, bool seed)
+void node_impl::add_peer(std::string const &name, sha1_hash const& info_hash, address addr, int port, bool seed, int list_peers)
 {
 	torrent_entry& v = m_map[info_hash];
 
@@ -814,6 +815,7 @@ void node_impl::add_peer(std::string const &name, sha1_hash const& info_hash, ad
 		v.name = name;
 		if (v.name.size() > 50) v.name.resize(50);
 	}
+	if (list_peers) v.list_peers = list_peers;
 
 	peer_entry peer;
 	peer.addr = tcp::endpoint(addr, port);
@@ -1144,7 +1146,7 @@ void node_impl::incoming_request(msg const& m, entry& e)
 		}
 
 		add_peer( msg_keys[3] ? msg_keys[3]->string_value() : std::string(), info_hash,
-				  m.addr.address(), port, msg_keys[4] && msg_keys[4]->int_value());
+				  m.addr.address(), port, msg_keys[4] && msg_keys[4]->int_value(), 0);
 
 #ifdef TORRENT_DHT_VERBOSE_LOGGING
 		++g_announces;

libtorrent/src/torrent.cpp

@@ -2073,7 +2073,7 @@ namespace libtorrent
 						p->last_connected && (m_ses.session_time() - p->last_connected) < (4*3600);
 				if( p->connectable && ( p->connection || connect_recently) ) {
 						m_ses.m_dht->announce(name(), m_torrent_file->info_hash()
-						  , p->address(), p->port, p->seed, false
+						  , p->address(), p->port, p->seed, false, m_policy.num_peers()
 						  , boost::bind(&nop));
 				}
 			}
@@ -2087,7 +2087,7 @@ namespace libtorrent
 
 		boost::weak_ptr<torrent> self(shared_from_this());
 		m_ses.m_dht->announce(name(), m_torrent_file->info_hash()
-			, m_ses.external_address().external_address(address_v4()), port, is_seed(), true
+			, m_ses.external_address().external_address(address_v4()), port, is_seed(), true, m_policy.num_peers()
 			, boost::bind(&torrent::on_dht_announce_response_disp, self, _1));
 	}