Fix corrupt neutral room list (#4412)

and a recalculation when it corrupts someplace else.

Author: PieterVdc

src/room_data.c

@@ -3144,25 +3144,24 @@ void kill_room_slab_and_contents(PlayerNumber plyr_idx, MapSlabCoord slb_x, MapS
 void free_room_structure(struct Room *room)
 {
     PlayerNumber owner = room->owner;
-    if ( game.neutral_player_num != owner )
-    {
-        struct Dungeon *dungeon = get_dungeon(owner);
 
-        if ( room->index == dungeon->room_list_start[room->kind] )
-        {
-            dungeon->room_list_start[room->kind] = room->next_of_owner;
-            struct Room *next_room = room_get(room->next_of_owner);
-            next_room->prev_of_owner = 0;
-        }
-        else
-        {
-            struct Room *next_room = room_get(room->next_of_owner);
-            next_room->prev_of_owner = room->prev_of_owner;
-            struct Room *prev_room = room_get(room->prev_of_owner);
-            prev_room->next_of_owner = room->next_of_owner;
-        }
-        --dungeon->room_discrete_count[room->kind];
+    struct Dungeon *dungeon = get_dungeon(owner);
+
+    if ( room->index == dungeon->room_list_start[room->kind] )
+    {
+        dungeon->room_list_start[room->kind] = room->next_of_owner;
+        struct Room *next_room = room_get(room->next_of_owner);
+        next_room->prev_of_owner = 0;
+    }
+    else
+    {
+        struct Room *next_room = room_get(room->next_of_owner);
+        next_room->prev_of_owner = room->prev_of_owner;
+        struct Room *prev_room = room_get(room->prev_of_owner);
+        prev_room->next_of_owner = room->next_of_owner;
     }
+    --dungeon->room_discrete_count[room->kind];
+
     remove_room_from_global_list(room);
     delete_room_structure(room);
 }

src/room_list.c

@@ -52,6 +52,31 @@ void clear_rooms(void)
   }
 }
 
+void recalculate_player_roomlist(PlayerNumber plyr_idx,RoomKind rkind)
+{
+    struct Dungeon* dungeon = get_dungeon(plyr_idx);
+
+    RoomIndex last_idx = 0;
+
+    for (RoomIndex room_idx = 0; room_idx < ROOMS_COUNT; room_idx++)
+    {
+        struct Room* room = &game.rooms[room_idx];
+        if (!room_is_invalid(room) && (room->owner == plyr_idx) && (room->kind == rkind))
+        {
+            if (last_idx != 0)
+            {
+                struct Room* last_room = &game.rooms[last_idx];
+                last_room->prev_of_owner = room->index;
+            }
+
+            room->next_of_owner = last_idx;
+            dungeon->room_list_start[rkind] = room->index;
+            last_idx = room->index;
+
+        }
+    }
+}
+
 /**
  * Counts amount of rooms of specific type owned by specific player.
  * @param plyr_idx The player number. Only specific player number is accepted.
@@ -85,7 +110,8 @@ long count_player_rooms_of_type(PlayerNumber plyr_idx, RoomKind rkind)
         k++;
         if (k > ROOMS_COUNT)
         {
-            ERRORLOG("Infinite loop detected when sweeping rooms list");
+            ERRORLOG("Infinite loop detected when sweeping rooms list %s for player %d",room_code_name(rkind),(int)plyr_idx);
+            recalculate_player_roomlist(plyr_idx, rkind);
             break;
         }
     }