better fix for failing pieces

include/libtorrent/torrent.hpp

@@ -505,6 +505,13 @@ namespace libtorrent
 		// test
 		void piece_finished(int index, int passed_hash_check);
 		void piece_failed(int index);
+
+		// this will restore the piece picker state for a piece
+		// by re marking all the requests to blocks in this piece
+		// that are still outstanding in peers' download queues.
+		// this is done when a piece fails
+		void restore_piece_state(int index);
+
 		void received_redundant_data(int num_bytes)
 		{ TORRENT_ASSERT(num_bytes > 0); m_total_redundant_bytes += num_bytes; }
 

src/piece_picker.cpp

@@ -1778,8 +1778,6 @@ namespace libtorrent
 		// this might be the case if a piece fails, is restored, and then
 		// completed from a different peer (from which the piece was requested
 		// before it failed the hash check)
-		if (m_piece_map[block.piece_index].downloading == 0)
-			mark_as_downloading(block, peer, piece_picker::none);
 
 		TORRENT_ASSERT(m_piece_map[block.piece_index].downloading);
 
@@ -1787,8 +1785,6 @@ namespace libtorrent
 			= std::find_if(m_downloads.begin(), m_downloads.end(), has_index(block.piece_index));
 		TORRENT_ASSERT(i != m_downloads.end());
 		block_info& info = i->info[block.block_index];
-		if (info.state == block_info::state_none)
-			mark_as_downloading(block, peer, piece_picker::none);
 
 		info.peer = peer;
 		TORRENT_ASSERT(info.state == block_info::state_requested);

src/torrent.cpp

@@ -1289,6 +1289,7 @@ namespace libtorrent
 		{
 			TORRENT_ASSERT(passed_hash_check == -1);
 			m_picker->restore_piece(index);
+			restore_piece_state(index);
 		}
 	}
 
@@ -1402,6 +1403,7 @@ namespace libtorrent
 		// start with redownloading the pieces that the client
 		// that has sent the least number of pieces
 		m_picker->restore_piece(index);
+		restore_piece_state(index);
 		TORRENT_ASSERT(m_storage);
 
 		TORRENT_ASSERT(m_picker->have_piece(index) == false);
@@ -1419,6 +1421,32 @@ namespace libtorrent
 #endif
 	}
 
+	void torrent::restore_piece_state(int index)
+	{
+		TORRENT_ASSERT(has_picker());
+		for (peer_iterator i = m_connections.begin();
+			i != m_connections.end(); ++i)
+		{
+			peer_connection* p = *i;
+			std::deque<piece_block> const& dq = p->download_queue();
+			std::deque<piece_block> const& rq = p->request_queue();
+			for (std::deque<piece_block>::const_iterator k = dq.begin()
+				, end(dq.end()); k != end; ++k)
+			{
+				if (k->piece_index != index) continue;
+				m_picker->mark_as_downloading(*k, p->peer_info_struct()
+					, (piece_picker::piece_state_t)p->peer_speed());
+			}
+			for (std::deque<piece_block>::const_iterator k = rq.begin()
+				, end(rq.end()); k != end; ++k)
+			{
+				if (k->piece_index != index) continue;
+				m_picker->mark_as_downloading(*k, p->peer_info_struct()
+					, (piece_picker::piece_state_t)p->peer_speed());
+			}
+		}
+	}
+
 	void torrent::abort()
 	{
 		INVARIANT_CHECK;