Made possession pickup rules for library objects the same as regular rules

src/spdigger_stack.c

@@ -56,7 +56,6 @@ extern "C" {
 DLLIMPORT long _DK_check_out_unreinforced_place(struct Thing *creatng);
 DLLIMPORT long _DK_check_out_unreinforced_area(struct Thing *creatng);
 DLLIMPORT struct Thing *_DK_check_place_to_pickup_gold(struct Thing *creatng, long stl_x, long stl_y);
-DLLIMPORT struct Thing *_DK_check_place_to_pickup_spell(struct Thing *creatng, long slb_x, long slb_y);
 DLLIMPORT struct Thing *_DK_check_place_to_pickup_unconscious_body(struct Thing *creatng, long slb_x, long slb_y);
 DLLIMPORT long _DK_imp_will_soon_be_converting_at_excluding(struct Thing *creatng, long slb_x, long slb_y);
 DLLIMPORT long _DK_imp_already_reinforcing_at_excluding(struct Thing *creatng, long stl_x, long stl_y);
@@ -2187,9 +2186,47 @@ struct Thing* check_place_to_pickup_gold(struct Thing* thing, MapSubtlCoord stl_
     return INVALID_THING;
 }
 
-struct Thing *check_place_to_pickup_spell(struct Thing *thing, long a2, long a3)
+TbBool creature_can_pickup_library_object_at_subtile(struct Thing* spdigtng, MapSubtlCoord stl_x, MapSubtlCoord stl_y)
 {
-    return _DK_check_place_to_pickup_spell(thing, a2, a3);
+    struct SlabMap* slb = get_slabmap_for_subtile(stl_x, stl_y);
+    if (slabmap_owner(slb) != spdigtng->owner)
+    {
+        return false;
+    }
+    return true;
+}
+
+struct Thing *check_place_to_pickup_spell(struct Thing *spdigtng, MapSubtlCoord stl_x, MapSubtlCoord stl_y)
+{
+    struct Thing *rettng;
+    if (!creature_can_pickup_library_object_at_subtile(spdigtng, stl_x, stl_y))
+    {
+        return INVALID_THING;
+    }
+    struct Map* mapblk = get_map_block_at(stl_x, stl_y);
+    rettng = thing_get(get_mapwho_thing_index(mapblk));
+    if (thing_is_invalid(rettng))
+    {
+        return INVALID_THING;
+    }
+    unsigned long k = 0;
+    while (!thing_can_be_picked_to_place_in_player_room(rettng, spdigtng->owner, RoK_LIBRARY, TngFRPickF_Default))
+    {
+        rettng = thing_get(rettng->next_on_mapblk);
+        if (thing_is_invalid(rettng))
+        {
+            return INVALID_THING;
+        }
+
+        k++;
+        if (k > THINGS_COUNT)
+        {
+            ERRORLOG("Infinite loop detected when sweeping things list");
+            break_mapwho_infinite_chain(mapblk);
+            break;
+        }
+    }
+    return rettng;
 }
 
 struct Thing *check_place_to_pickup_unconscious_body(struct Thing *thing, long a2, long a3)

src/spdigger_stack.h

@@ -113,6 +113,7 @@ long imp_already_reinforcing_at_excluding(struct Thing *creatng, MapSubtlCoord s
 
 TbBool thing_can_be_picked_to_place_in_player_room(const struct Thing* thing, PlayerNumber plyr_idx, RoomKind rkind, unsigned short flags);
 long get_random_mining_undug_area_position_for_digger_drop(PlayerNumber plyr_idx, MapSubtlCoord *retstl_x, MapSubtlCoord *retstl_y);
+TbBool creature_can_pickup_library_object_at_subtile(struct Thing* spdigtng, MapSubtlCoord stl_x, MapSubtlCoord stl_y);
 
 TbBool imp_stack_update(struct Thing *creatng);
 TbBool check_out_imp_stack(struct Thing *creatng);

src/thing_creature.c

@@ -5994,6 +5994,10 @@ TbBool thing_is_pickable_by_digger(struct Thing *picktng, struct Thing *creatng)
     }
     else if (thing_can_be_picked_to_place_in_player_room(picktng, creatng->owner, RoK_LIBRARY, TngFRPickF_Default))
     {
+        if(!creature_can_pickup_library_object_at_subtile(creatng, picktng->mappos.x.stl.num, picktng->mappos.y.stl.num))
+        {
+            return false;
+        }
         return (get_room_slabs_count(creatng->owner, RoK_LIBRARY) > 0);
     }
     else if (thing_can_be_picked_to_place_in_player_room(picktng, creatng->owner, RoK_WORKSHOP, TngFRPickF_Default))