add per-tracker scrape information to announce_entry

ChangeLog

@@ -1,3 +1,4 @@
+	* add per-tracker scrape information to announce_entry
 	* report errors in read_piece_alert
 	* DHT memory optimization
 	* improve DHT lookup speed

docs/manual.rst

@@ -2126,6 +2126,10 @@ ones with lower tier will always be tried before the one with higher tier number
 		int next_announce_in() const;
 		int min_announce_in() const;
 
+		int scrape_incomplete;
+		int scrape_complete;
+		int scrape_downloaded;
+
 		error_code last_error;
 
 		std::string message;
@@ -2156,6 +2160,13 @@ allowed to force another tracker update with this tracker.
 If the last time this tracker was contacted failed, ``last_error`` is the error
 code describing what error occurred.
 
+``scrape_incomplete``, ``scrape_complete`` and ``scrape_downloaded`` are either
+-1 or the scrape information this tracker last responded with. *incomplete* is
+the current number of downloaders in the swarm, *complete* is the current number
+of seeds in the swarm and *downloaded* is the cumulative number of completed
+downloads of this torrent, since the beginning of time (from this tracker's point
+of view).
+
 If the last time this tracker was contacted, the tracker returned a warning
 or error message, ``message`` contains that message.
 
@@ -6703,8 +6714,9 @@ the DHT.
 		int num_peers;
 	};
 
-The ``num_peers`` tells how many peers were returned from the tracker. This is
+The ``num_peers`` tells how many peers the tracker returned in this response. This is
-not necessarily all new peers, some of them may already be connected.
+not expected to be more thant the ``num_want`` settings. These are not necessarily
+all new peers, some of them may already be connected.
 
 tracker_warning_alert
 ---------------------

include/libtorrent/torrent.hpp

@@ -448,8 +448,8 @@ namespace libtorrent
 			, address const& tracker_ip
 			, std::list<address> const& ip_list
 			, std::vector<peer_entry>& e, int interval, int min_interval
-			, int complete, int incomplete, address const& external_ip
+			, int complete, int incomplete, int downloaded
-			, std::string const& trackerid);
+			, address const& external_ip, std::string const& trackerid);
 		virtual void tracker_request_error(tracker_request const& r
 			, int response_code, error_code const& ec, const std::string& msg
 			, int retry_interval);
@@ -458,6 +458,8 @@ namespace libtorrent
 		virtual void tracker_scrape_response(tracker_request const& req
 			, int complete, int incomplete, int downloaded, int downloaders);
 
+		void update_scrape_state();
+
 		// if no password and username is set
 		// this will return an empty string, otherwise
 		// it will concatenate the login and password
@@ -1338,7 +1340,7 @@ namespace libtorrent
 
 		// the scrape data from the tracker response, this
 		// is optional and may be 0xffffff
-		unsigned int m_downloaders:24;
+		unsigned int m_downloaded:24;
 
 		// round-robin index into m_interfaces
 		mutable boost::uint8_t m_interface_index;

include/libtorrent/torrent_info.hpp

@@ -105,6 +105,17 @@ namespace libtorrent
 		// no announces before this time
 		ptime min_announce;
 
+		// TODO: include the number of peers received from this tracker, at last announce
+
+		// if this tracker has returned scrape data, these fields are filled
+		// in with valid numbers. Otherwise they are set to -1.
+		// the number of current downloaders
+		int scrape_incomplete;
+		// the number of current seeds
+		int scrape_complete;
+		// the cumulative number of completed downloads, ever
+		int scrape_downloaded;
+
 		// the tier this tracker belongs to
 		boost::uint8_t tier;
 

include/libtorrent/tracker_manager.hpp

@@ -156,6 +156,7 @@ namespace libtorrent
 			, int min_interval
 			, int complete
 			, int incomplete
+			, int downloaded
 			, address const& external_ip
 			, std::string const& trackerid) = 0;
 		virtual void tracker_request_error(

src/http_tracker_connection.cpp

@@ -527,6 +527,7 @@ namespace libtorrent
 		
 		int complete = int(e.dict_find_int_value("complete", -1));
 		int incomplete = int(e.dict_find_int_value("incomplete", -1));
+		int downloaded = int(e.dict_find_int_value("downloaded", -1));
 
 		std::list<address> ip_list;
 		if (m_tracker_connection)
@@ -542,7 +543,7 @@ namespace libtorrent
 		}
 
 		cb->tracker_response(tracker_req(), m_tracker_ip, ip_list, peer_list
-			, interval, min_interval, complete, incomplete, external_ip, trackerid);
+			, interval, min_interval, complete, incomplete, downloaded, external_ip, trackerid);
 	}
 
 }

src/torrent.cpp

@@ -415,7 +415,7 @@ namespace libtorrent
 		, m_last_download(0)
 		, m_last_upload(0)
 		, m_last_scrape(0)
-		, m_downloaders(0xffffff)
+		, m_downloaded(0xffffff)
 		, m_interface_index(0)
 		, m_graceful_pause_mode(false)
 		, m_need_connect_boost(true)
@@ -2470,21 +2470,47 @@ namespace libtorrent
  		INVARIANT_CHECK;
 		TORRENT_ASSERT(req.kind == tracker_request::scrape_request);
  
-		if ((complete >= 0 && m_complete != complete)
+		announce_entry* ae = find_tracker(req);
-			|| (incomplete >= 0 && m_incomplete != incomplete)
+		if (ae)
-			|| (downloaders >= 0 && m_downloaders != downloaders))
+		{
-			state_updated();
+			if (incomplete >= 0) ae->scrape_incomplete = incomplete;
+			if (complete >= 0) ae->scrape_complete = complete;
+			if (downloaded >= 0) ae->scrape_downloaded = downloaded;
 
-		if (complete >= 0) m_complete = complete;
+			update_scrape_state();
-		if (incomplete >= 0) m_incomplete = incomplete;
+		}
-		if (downloaders >= 0) m_downloaders = downloaders;
 
 		if (m_ses.m_alerts.should_post<scrape_reply_alert>())
 		{
 			m_ses.m_alerts.post_alert(scrape_reply_alert(
-				get_handle(), m_incomplete, m_complete, req.url));
+				get_handle(), incomplete, complete, req.url));
 		}
 	}
+
+	void torrent::update_scrape_state()
+	{
+		// loop over all trackers and find the largest numbers for each scrape field
+		// then update the torrent-wide understanding of number of downloaders and seeds
+		int complete = -1;
+		int incomplete = -1;
+		int downloaded = -1;
+		for (std::vector<announce_entry>::iterator i = m_trackers.begin()
+			, end(m_trackers.end()); i != end; ++i)
+		{
+			complete = (std::max)(i->scrape_complete, complete);
+			incomplete = (std::max)(i->scrape_incomplete, incomplete);
+			downloaded = (std::max)(i->scrape_downloaded, downloaded);
+		}
+
+		if ((complete >= 0 && m_complete != complete)
+			|| (incomplete >= 0 && m_incomplete != incomplete)
+			|| (downloaded >= 0 && m_downloaded != downloaded))
+			state_updated();
+
+		m_complete = complete;
+		m_incomplete = incomplete;
+		m_downloaded = downloaded;
+	}
  
 	void torrent::tracker_response(
 		tracker_request const& r
@@ -2495,6 +2521,7 @@ namespace libtorrent
 		, int min_interval
 		, int complete
 		, int incomplete
+		, int downloaded 
 		, address const& external_ip
 		, const std::string& trackerid)
 	{
@@ -2516,6 +2543,9 @@ namespace libtorrent
 		announce_entry* ae = find_tracker(r);
 		if (ae)
 		{
+			if (incomplete >= 0) ae->scrape_incomplete = incomplete;
+			if (complete >= 0) ae->scrape_complete = complete;
+			if (downloaded >= 0) ae->scrape_downloaded = downloaded;
 			if (!ae->start_sent && r.event == tracker_request::started)
 				ae->start_sent = true;
 			if (!ae->complete_sent && r.event == tracker_request::completed)
@@ -2534,11 +2564,11 @@ namespace libtorrent
 				if (m_ses.m_alerts.should_post<trackerid_alert>())
 				m_ses.m_alerts.post_alert(trackerid_alert(get_handle(), r.url, trackerid));
 			}
+
+			update_scrape_state();
 		}
 		update_tracker_timer(now);
 
-		if (complete >= 0) m_complete = complete;
-		if (incomplete >= 0) m_incomplete = incomplete;
 		if (complete >= 0 && incomplete >= 0)
 			m_last_scrape = 0;
 
@@ -5033,9 +5063,9 @@ namespace libtorrent
 		m_finished_time = rd.dict_find_int_value("finished_time");
 		m_seeding_time = rd.dict_find_int_value("seeding_time");
 		m_last_seen_complete = rd.dict_find_int_value("last_seen_complete");
-		m_complete = rd.dict_find_int_value("num_seeds", 0xffffff);
+		m_complete = rd.dict_find_int_value("num_complete", 0xffffff);
 		m_incomplete = rd.dict_find_int_value("num_incomplete", 0xffffff);
-		m_downloaders = rd.dict_find_int_value("num_downloaders", 0xffffff);
+		m_downloaded = rd.dict_find_int_value("num_downloaded", 0xffffff);
 		set_upload_limit(rd.dict_find_int_value("upload_rate_limit", -1));
 		set_download_limit(rd.dict_find_int_value("download_rate_limit", -1));
 		set_max_connections(rd.dict_find_int_value("max_connections", -1));
@@ -5231,9 +5261,9 @@ namespace libtorrent
 		ret["seeding_time"] = m_seeding_time;
 		ret["last_seen_complete"] = m_last_seen_complete;
 
-		ret["num_seeds"] = m_complete;
+		ret["num_complete"] = m_complete;
 		ret["num_incomplete"] = m_incomplete;
-		ret["num_downloaders"] = m_downloaders;
+		ret["num_downloaded"] = m_downloaded;
 
 		ret["sequential_download"] = m_sequential_download;
 
@@ -7063,8 +7093,7 @@ namespace libtorrent
 		if (m_complete != 0xffffff) seeds = m_complete;
 		else seeds = m_policy.num_seeds();
 
-		if (m_downloaders != 0xffffff) downloaders = m_downloaders;
+		if (m_incomplete != 0xffffff) downloaders = m_incomplete;
-		else if (m_incomplete != 0xffffff) downloaders = m_incomplete;
 		else downloaders = m_policy.num_peers() - m_policy.num_seeds();
 
 		if (seeds == 0)

src/torrent_info.cpp

@@ -454,6 +454,9 @@ namespace libtorrent
 		: url(u)
 		, next_announce(min_time())
 		, min_announce(min_time())
+		, scrape_incomplete(-1)
+		, scrape_complete(-1)
+		, scrape_downloaded(-1)
 		, tier(0)
 		, fail_limit(0)
 		, fails(0)

src/udp_tracker_connection.cpp

@@ -569,7 +569,7 @@ namespace libtorrent
 		}
 
 		cb->tracker_response(tracker_req(), m_target.address(), ip_list
-			, peer_list, interval, min_interval, complete, incomplete, address(), "" /*trackerid*/);
+			, peer_list, interval, min_interval, complete, incomplete, 0, address(), "" /*trackerid*/);
 
 		close();
 		return true;