better exception handling and more invariant checks

src/peer_connection.cpp

@@ -396,6 +396,7 @@ namespace libtorrent
 	peer_connection::~peer_connection()
 	{
 //		INVARIANT_CHECK;
+		TORRENT_ASSERT(!m_in_constructor);
 		TORRENT_ASSERT(m_disconnecting);
 
 #ifdef TORRENT_VERBOSE_LOGGING
@@ -627,6 +628,7 @@ namespace libtorrent
 		// check to make sure we don't have another connection with the same
 		// info_hash and peer_id. If we do. close this connection.
 		t->attach_peer(this);
+		if (m_disconnecting) return;
 		m_torrent = wpt;
 
 		TORRENT_ASSERT(!m_torrent.expired());
@@ -2048,16 +2050,19 @@ namespace libtorrent
 #if defined(TORRENT_VERBOSE_LOGGING)
 		(*m_logger) << "*** CONNECTION FAILED " << message << "\n";
 #endif
+		// we cannot create an intrusive pointer to ourselves, since we
+		// might be calling disconnect from the constructor (which would
+		// delete ourselves before the constructor returns)
 //		boost::intrusive_ptr<peer_connection> me(this);
 
 		INVARIANT_CHECK;
 
 		if (m_disconnecting) return;
-		m_disconnecting = true;
-		if (m_connecting)
+		if (m_connecting && m_connection_ticket >= 0)
+		{
 			m_ses.m_half_open.done(m_connection_ticket);
-
-		m_ses.m_io_service.post(boost::bind(&close_socket_ignore_error, m_socket));
+			m_connection_ticket = -1;
+		}
 
 		boost::shared_ptr<torrent> t = m_torrent.lock();
 
@@ -2092,7 +2097,11 @@ namespace libtorrent
 			m_torrent.reset();
 		}
 
+		boost::shared_ptr<socket_type> sock = m_socket;
+		m_disconnecting = true;
 		m_ses.close_connection(this, message);
+
+		m_ses.m_io_service.post(boost::bind(&close_socket_ignore_error, sock));
 	}
 
 	void peer_connection::set_upload_limit(int limit)
@@ -3004,6 +3013,18 @@ namespace libtorrent
 #ifndef NDEBUG
 	void peer_connection::check_invariant() const
 	{
+		if (m_disconnecting)
+		{
+			for (aux::session_impl::torrent_map::const_iterator i = m_ses.m_torrents.begin()
+				, end(m_ses.m_torrents.end()); i != end; ++i)
+				TORRENT_ASSERT(!i->second->has_peer((peer_connection*)this));
+			TORRENT_ASSERT(!m_torrent.lock());
+		}
+		else if (!m_in_constructor)
+		{
+			TORRENT_ASSERT(m_ses.has_peer((peer_connection*)this));
+		}
+
 		for (int i = 0; i < 2; ++i)
 		{
 			// this peer is in the bandwidth history iff max_assignable < limit
@@ -3253,7 +3274,6 @@ namespace libtorrent
 
 	bool peer_connection::is_seed() const
 	{
-		INVARIANT_CHECK;
 		// if m_num_pieces == 0, we probably don't have the
 		// metadata yet.
 		return m_num_pieces == (int)m_have_piece.size() && m_num_pieces > 0;

src/session_impl.cpp

@@ -2475,6 +2475,7 @@ namespace detail
 			boost::shared_ptr<torrent> t = (*i)->associated_torrent().lock();
 
 			peer_connection* p = i->get();
+			TORRENT_ASSERT(!p->is_disconnecting());
 			if (!p->is_choked()) ++unchokes;
 			if (p->peer_info_struct()
 				&& p->peer_info_struct()->optimistically_unchoked)

src/torrent.cpp

@@ -2195,8 +2195,6 @@ namespace libtorrent
 			throw protocol_error("reached connection limit");
 		}
 
-		TORRENT_ASSERT(m_connections.find(p) == m_connections.end());
-		peer_iterator ci = m_connections.insert(p).first;
 		try
 		{
 			// if new_connection throws, we have to remove the
@@ -2210,13 +2208,8 @@ namespace libtorrent
 				if (pp) p->add_extension(pp);
 			}
 #endif
-			TORRENT_ASSERT(m_connections.find(p) == ci);
-			TORRENT_ASSERT(*ci == p);
-			if (!m_policy.new_connection(**ci))
-			{
-				m_connections.erase(ci);
+			if (!m_policy.new_connection(*p))
 				return;
-			}
 		}
 		catch (std::exception& e)
 		{
@@ -2224,9 +2217,10 @@ namespace libtorrent
 			(*m_ses.m_logger) << time_now_string() << " CLOSING CONNECTION "
 				<< p->remote() << " policy::new_connection threw: " << e.what() << "\n";
 #endif
-			m_connections.erase(ci);
 			throw;
 		}
+		TORRENT_ASSERT(m_connections.find(p) == m_connections.end());
+		peer_iterator ci = m_connections.insert(p).first;
 		TORRENT_ASSERT(p->remote() == p->get_socket()->remote_endpoint());
 
 #ifndef NDEBUG