(svn r14876) -Fix [FS#2509] (r14849): Reserved path loop detection was broken for stations.

Don't set the test tile to the tile the very first iteration handles. Update the test tile instead in the loop.

src/pbs.cpp

@@ -181,6 +181,7 @@ static PBSTileInfo FollowReservation(Owner o, RailTypes rts, TileIndex tile, Tra
 {
 	TileIndex start_tile = tile;
 	Trackdir  start_trackdir = trackdir;
+	bool      first_loop = true;
 
 	/* Start track not reserved? This can happen if two trains
 	 * are on the same tile. The reservation on the next tile
@@ -189,14 +190,6 @@ static PBSTileInfo FollowReservation(Owner o, RailTypes rts, TileIndex tile, Tra
 
 	/* Do not disallow 90 deg turns as the setting might have changed between reserving and now. */
 	CFollowTrackRail ft(o, rts);
-
-	/* If the start tile is in a station, we need to skip to the platform
-	 * end and use that as the tile for the loop test because the track
-	 * follower will skip to there in the actual loop as well. */
-	if (IsRailwayStationTile(start_tile) && ft.Follow(start_tile, start_trackdir) && ft.m_tiles_skipped > 0) {
-		start_tile = ft.m_new_tile;
-	}
-
 	while (ft.Follow(tile, trackdir)) {
 		TrackdirBits reserved = ft.m_new_td_bits & TrackBitsToTrackdirBits(GetReservedTrackbits(ft.m_new_tile));
 
@@ -213,8 +206,18 @@ static PBSTileInfo FollowReservation(Owner o, RailTypes rts, TileIndex tile, Tra
 		tile = ft.m_new_tile;
 		trackdir = new_trackdir;
 
-		/* Loop encountered? */
-		if (tile == start_tile && trackdir == start_trackdir) break;
+		if (first_loop) {
+			/* Update the start tile after we followed the track the first
+			 * time. This is neccessary because the track follower can skip
+			 * tiles (in stations for example) which means that we might
+			 * never visit our original starting tile again. */
+			start_tile = tile;
+			start_trackdir = trackdir;
+			first_loop = false;
+		} else {
+			/* Loop encountered? */
+			if (tile == start_tile && trackdir == start_trackdir) break;
+		}
 		/* Depot tile? Can't continue. */
 		if (IsRailDepotTile(tile)) break;
 		/* Non-pbs signal? Reservation can't continue. */