fixed error handling with torrents with invalid piece sizes

ChangeLog

@@ -106,6 +106,7 @@
 	* improved LSD performance and made the interval configurable
 	* improved UDP tracker support by caching connect tokens
 	* fast piece optimization
+	* fixed error handling with torrents with invalid piece sizes
 	* fixed issue with disk read cache not being cleared when removing torrents
 
 release 0.14.9

docs/manual.rst

@@ -6275,7 +6275,8 @@ code   symbol                                    description
 ------ ----------------------------------------- -----------------------------------------------------------------
 81     packet_too_large                          The packet size exceeded the upper sanity check-limit
 ------ ----------------------------------------- -----------------------------------------------------------------
-82     reserved                                                                    
+82     torrent_invalid_piece_size                The .torrent file has an invalid piece size. It needs to be an
+                                                 even 16 kiB multiple
 ------ ----------------------------------------- -----------------------------------------------------------------
 83     http_error                                The web server responded with an error
 ------ ----------------------------------------- -----------------------------------------------------------------

include/libtorrent/error_code.hpp

@@ -139,7 +139,7 @@ namespace libtorrent
 			duplicate_peer_id,
 			torrent_removed,
 			packet_too_large,
-			reserved82,
+			torrent_invalid_piece_size,
 			http_error,
 			missing_location,
 			invalid_redirection,

src/error_code.cpp

@@ -130,7 +130,7 @@ namespace libtorrent
 			"duplicate peer-id",
 			"torrent removed",
 			"packet too large",
-			"",
+			"invalid piece size in torrent file",
 			"HTTP error",
 			"missing location header",
 			"invalid redirection",

src/piece_picker.cpp

@@ -474,6 +474,7 @@ namespace libtorrent
 		TORRENT_ASSERT(m_seeds >= 0);
 		const int num_pieces = m_piece_map.size();
 
+		if (num_pieces == 0) return std::make_pair(1, 0);
 		int min_availability = piece_pos::max_peer_count;
 		// find the lowest availability count
 		// count the number of pieces that have that availability

src/torrent.cpp

@@ -814,6 +814,15 @@ namespace libtorrent
 		{
 			set_error(errors::too_many_pieces_in_torrent, "");
 			pause();
+			return;
+		}
+
+		if (m_torrent_file->piece_length() % block_size() != 0)
+		{
+			// TODO: try to adjust the block size
+			set_error(errors::torrent_invalid_piece_size, "");
+			pause();
+			return;
 		}
 
 		// the shared_from_this() will create an intentional
@@ -4783,11 +4792,11 @@ namespace libtorrent
 
 		if (valid_metadata())
 		{
-			TORRENT_ASSERT(m_abort || !m_picker || m_picker->num_pieces() == m_torrent_file->num_pieces());
+			TORRENT_ASSERT(m_abort || m_error || !m_picker || m_picker->num_pieces() == m_torrent_file->num_pieces());
 		}
 		else
 		{
-			TORRENT_ASSERT(m_abort || !m_picker || m_picker->num_pieces() == 0);
+			TORRENT_ASSERT(m_abort || m_error || !m_picker || m_picker->num_pieces() == 0);
 		}
 
 #ifdef TORRENT_EXPENSIVE_INVARIANT_CHECKS
@@ -4844,7 +4853,7 @@ namespace libtorrent
 			}
 		}
 			
-		if (valid_metadata())
+		if (m_files_checked && valid_metadata())
 		{
 			TORRENT_ASSERT(block_size() > 0);
 			TORRENT_ASSERT((m_torrent_file->piece_length() & (block_size()-1)) == 0);
@@ -5024,6 +5033,8 @@ namespace libtorrent
 			m_ses.m_auto_manage_time_scaler = 2;
 		m_error = error_code();
 		m_error_file.clear();
+		// if the error happened during initialization, try again now
+		if (!m_storage) init();
 		if (!checking_files && should_check_files())
 			queue_torrent_check();
 	}