asio handlers are now properly cancelled when destructing the session object, race conditions are avoided by waiting for the io service to complete all tasks

include/libtorrent/aux_/session_impl.hpp

@@ -375,12 +375,6 @@ namespace libtorrent
 			// buffers from.
 			boost::pool<> m_send_buffers;
 
-			// this is where all active sockets are stored.
-			// the selector can sleep while there's no activity on
-			// them
-			io_service m_io_service;
-			asio::strand m_strand;
-
 			// the file pool that all storages in this session's
 			// torrents uses. It sets a limit on the number of
 			// open files by this session.
@@ -395,6 +389,12 @@ namespace libtorrent
 			// object.
 			disk_io_thread m_disk_thread;
 
+			// this is where all active sockets are stored.
+			// the selector can sleep while there's no activity on
+			// them
+			io_service m_io_service;
+			asio::strand m_strand;
+
 			// this is a list of half-open tcp connections
 			// (only outgoing connections)
 			// this has to be one of the last
@@ -646,7 +646,7 @@ namespace libtorrent
 			
 			void debug_log(const std::string& line)
 			{
-				(*m_ses.m_logger) << line << "\n";
+				(*m_ses.m_logger) << time_now_string() << " " << line << "\n";
 			}
 			session_impl& m_ses;
 		};

include/libtorrent/connection_queue.hpp

@@ -56,6 +56,7 @@ public:
 	void done(int ticket);
 	void limit(int limit);
 	int limit() const;
+	void close();
 
 #ifndef NDEBUG
 

include/libtorrent/http_tracker_connection.hpp

@@ -130,6 +130,8 @@ namespace libtorrent
 			, proxy_settings const& ps
 			, std::string const& password = "");
 
+		void close();
+
 	private:
 
 		boost::intrusive_ptr<http_tracker_connection> self()

include/libtorrent/tracker_manager.hpp

@@ -202,7 +202,7 @@ namespace libtorrent
 
 		void fail(int code, char const* msg);
 		void fail_timeout();
-		void close();
+		virtual void close();
 		address const& bind_interface() const { return m_bind_interface; }
 
 	protected:

include/libtorrent/udp_tracker_connection.hpp

@@ -74,6 +74,8 @@ namespace libtorrent
 			, boost::weak_ptr<request_callback> c
 			, session_settings const& stn);
 
+		void close();
+
 	private:
 
 		enum action_t

src/connection_queue.cpp

@@ -86,6 +86,11 @@ namespace libtorrent
 		try_connect();
 	}
 
+	void connection_queue::close()
+	{
+		m_timer.cancel();
+	}
+
 	void connection_queue::limit(int limit)
 	{ m_half_open_limit = limit; }
 

src/http_tracker_connection.cpp

@@ -489,7 +489,9 @@ namespace libtorrent
 			, boost::lexical_cast<std::string>(m_port));
 		m_name_lookup.async_resolve(q, m_strand.wrap(
 			boost::bind(&http_tracker_connection::name_lookup, self(), _1, _2)));
-		set_timeout(m_settings.tracker_completion_timeout
+		set_timeout(req.event == tracker_request::stopped
+			? m_settings.stop_tracker_timeout
+			: m_settings.tracker_completion_timeout
 			, m_settings.tracker_receive_timeout);
 	}
 
@@ -503,6 +505,17 @@ namespace libtorrent
 		fail_timeout();
 	}
 
+	void http_tracker_connection::close()
+	{
+		asio::error_code ec;
+		m_socket.close(ec);
+		m_name_lookup.cancel();
+		if (m_connection_ticket > -1) m_cc.done(m_connection_ticket);
+		m_connection_ticket = -1;
+		m_timed_out = true;
+		tracker_connection::close();
+	}
+
 	void http_tracker_connection::name_lookup(asio::error_code const& error
 		, tcp::resolver::iterator i) try
 	{
@@ -759,7 +772,6 @@ namespace libtorrent
 		if (m_parser.status_code() != 200)
 		{
 			fail(m_parser.status_code(), m_parser.message().c_str());
-			close();
 			return;
 		}
 	
@@ -821,6 +833,7 @@ namespace libtorrent
 			TORRENT_ASSERT(false);
 		}
 		#endif
+		close();
 	}
 
 	peer_entry http_tracker_connection::extract_peer_info(const entry& info)

src/session_impl.cpp

@@ -547,8 +547,8 @@ namespace detail
 		, fingerprint const& cl_fprint
 		, char const* listen_interface)
 		: m_send_buffers(send_buffer_size)
-		, m_strand(m_io_service)
 		, m_files(40)
+		, m_strand(m_io_service)
 		, m_half_open(m_io_service)
 		, m_download_channel(m_io_service, peer_connection::download_channel)
 		, m_upload_channel(m_io_service, peer_connection::upload_channel)
@@ -675,6 +675,14 @@ namespace detail
 		if (m_dht) m_dht->stop();
 #endif
 		m_timer.cancel();
+
+		// close the listen sockets
+		for (std::list<listen_socket_t>::iterator i = m_listen_sockets.begin()
+			, end(m_listen_sockets.end()); i != end; ++i)
+		{
+			i->sock->close();
+		}
+
 		// abort all torrents
 		for (torrent_map::iterator i = m_torrents.begin()
 			, end(m_torrents.end()); i != end; ++i)
@@ -682,7 +690,15 @@ namespace detail
 			i->second->abort();
 		}
 
-		m_io_service.stop(); 
+#if defined(TORRENT_VERBOSE_LOGGING) || defined(TORRENT_LOGGING)
+		(*m_logger) << time_now_string() << " aborting all tracker requests\n";
+#endif
+		m_tracker_manager.abort_all_requests();
+
+#if defined(TORRENT_VERBOSE_LOGGING) || defined(TORRENT_LOGGING)
+		(*m_logger) << time_now_string() << " shutting down connection queue\n";
+#endif
+		m_half_open.close();
 
 		mutex::scoped_lock l2(m_checker_impl.m_mutex);
 		// abort the checker thread
@@ -1474,20 +1490,12 @@ namespace detail
 		while (!m_abort);
 
 		deadline_timer tracker_timer(m_io_service);
-		// this will remove the port mappings
-		if (m_natpmp.get())
-			m_natpmp->close();
-		if (m_upnp.get())
-			m_upnp->close();
 
 #if defined(TORRENT_VERBOSE_LOGGING) || defined(TORRENT_LOGGING)
 		(*m_logger) << time_now_string() << " locking mutex\n";
 #endif
 		session_impl::mutex_t::scoped_lock l(m_mutex);
 
-#if defined(TORRENT_VERBOSE_LOGGING) || defined(TORRENT_LOGGING)
-		(*m_logger) << time_now_string() << " aborting all tracker requests\n";
-#endif
 		m_tracker_manager.abort_all_requests();
 #if defined(TORRENT_VERBOSE_LOGGING) || defined(TORRENT_LOGGING)
 		(*m_logger) << time_now_string() << " sending stopped to all torrent's trackers\n";
@@ -2127,16 +2135,10 @@ namespace detail
 
 	session_impl::~session_impl()
 	{
-		abort();
-
 #if defined(TORRENT_VERBOSE_LOGGING) || defined(TORRENT_LOGGING)
 		(*m_logger) << time_now_string() << "\n\n *** shutting down session *** \n\n";
 #endif
-		// lock the main thread and abort it
+		abort();
-		mutex_t::scoped_lock l(m_mutex);
-		m_abort = true;
-		m_io_service.stop();
-		l.unlock();
 
 #if defined(TORRENT_VERBOSE_LOGGING) || defined(TORRENT_LOGGING)
 		(*m_logger) << time_now_string() << " waiting for main thread\n";

src/torrent.cpp

@@ -3055,7 +3055,7 @@ namespace libtorrent
 #if defined(TORRENT_VERBOSE_LOGGING) || defined(TORRENT_LOGGING)
 	void torrent::debug_log(const std::string& line)
 	{
-		(*m_ses.m_logger) << line << "\n";
+		(*m_ses.m_logger) << time_now_string() << " " << line << "\n";
 	}
 #endif
 

src/tracker_manager.cpp

@@ -302,12 +302,12 @@ namespace libtorrent
 	{
 		m_completion_timeout = completion_timeout;
 		m_read_timeout = read_timeout;
-		m_start_time = time_now();
+		m_start_time = m_read_time = time_now();
-		m_read_time = time_now();
 
 		m_timeout.expires_at((std::min)(
 			m_read_time + seconds(m_read_timeout)
-			, m_start_time + seconds(m_completion_timeout)));
+			, m_start_time + seconds((std::min)(m_completion_timeout
+			, m_read_timeout))));
 		m_timeout.async_wait(m_strand.wrap(bind(
 			&timeout_handler::timeout_callback, self(), _1)));
 	}
@@ -343,7 +343,8 @@ namespace libtorrent
 
 		m_timeout.expires_at((std::min)(
 			m_read_time + seconds(m_read_timeout)
-			, m_start_time + seconds(m_completion_timeout)));
+			, m_start_time + seconds((std::min)(m_completion_timeout
+			, m_read_timeout))));
 		m_timeout.async_wait(m_strand.wrap(
 			bind(&timeout_handler::timeout_callback, self(), _1)));
 	}
@@ -570,9 +571,12 @@ namespace libtorrent
 		for (tracker_connections_t::const_iterator i =
 			m_connections.begin(); i != m_connections.end(); ++i)
 		{
+			if (!*i) continue;
 			tracker_request const& req = (*i)->tracker_req();
 			if (req.event == tracker_request::stopped)
 				keep_connections.push_back(*i);
+			else
+				(*i)->close();
 		}
 
 		std::swap(m_connections, keep_connections);

src/udp_tracker_connection.cpp

@@ -96,7 +96,9 @@ namespace libtorrent
 		m_name_lookup.async_resolve(q
 			, m_strand.wrap(boost::bind(
 			&udp_tracker_connection::name_lookup, self(), _1, _2)));
-		set_timeout(m_settings.tracker_completion_timeout
+		set_timeout(req.event == tracker_request::stopped
+			? m_settings.stop_tracker_timeout
+			: m_settings.tracker_completion_timeout
 			, m_settings.tracker_receive_timeout);
 	}
 
@@ -156,11 +158,20 @@ namespace libtorrent
 
 	void udp_tracker_connection::on_timeout()
 	{
-		m_socket.close();
+		asio::error_code ec;
+		m_socket.close(ec);
 		m_name_lookup.cancel();
 		fail_timeout();
 	}
 
+	void udp_tracker_connection::close()
+	{
+		asio::error_code ec;
+		m_socket.close(ec);
+		m_name_lookup.cancel();
+		tracker_connection::close();
+	}
+
 	void udp_tracker_connection::send_udp_connect()
 	{
 #if defined(TORRENT_VERBOSE_LOGGING) || defined(TORRENT_LOGGING)
@@ -468,6 +479,7 @@ namespace libtorrent
 			, complete, incomplete);
 
 		m_man.remove_request(this);
+		close();
 		return;
 	}
 	catch (std::exception& e)
@@ -543,6 +555,7 @@ namespace libtorrent
 		if (!cb)
 		{
 			m_man.remove_request(this);
+			close();
 			return;
 		}
 		
@@ -551,6 +564,7 @@ namespace libtorrent
 			, complete, incomplete);
 
 		m_man.remove_request(this);
+		close();
 	}
 	catch (std::exception& e)
 	{