unpaid object sanity checking

Handle items in gaps of a wall shared between adjacent shops.

Make handling of shop boundaries more explicit:  walls, the door,
and the "free spot" by the door aren't classified as 'costly' but
obj->unpaid and obj->no_charge are valid there.

Move unpaid/no_charge checking into its own routine to unclutter
objlist_sanity().

Pushing a shop-owned boulder to the free spot or doorway or gap in
wall triggers the sanity check for the time being.

include/extern.h

@@ -2480,6 +2480,7 @@ extern boolean same_price(struct obj *, struct obj *);
 extern void shopper_financial_report(void);
 extern int inhishop(struct monst *);
 extern struct monst *shop_keeper(char);
+extern struct monst *find_objowner(struct obj *, coordxy x, coordxy y);
 extern boolean tended_shop(struct mkroom *);
 extern boolean onshopbill(struct obj *, struct monst *, boolean);
 extern boolean is_unpaid(struct obj *);
@@ -2518,6 +2519,7 @@ extern boolean is_fshk(struct monst *);
 extern void shopdig(int);
 extern void pay_for_damage(const char *, boolean);
 extern boolean costly_spot(coordxy, coordxy);
+extern boolean costly_adjacent(struct monst *, coordxy, coordxy);
 extern struct obj *shop_object(coordxy, coordxy);
 extern void price_quote(struct obj *);
 extern void shk_chat(struct monst *);

src/mkobj.c

@@ -13,6 +13,7 @@ static void obj_timer_checks(struct obj *, coordxy, coordxy, int);
 static void container_weight(struct obj *);
 static struct obj *save_mtraits(struct obj *, struct monst *);
 static void objlist_sanity(struct obj *, int, const char *);
+static void shop_obj_sanity(struct obj *, const char *);
 static void mon_obj_sanity(struct monst *, const char *);
 static void insane_obj_bits(struct obj *, struct monst *);
 static boolean nomerge_exception(struct obj *);
@@ -2722,10 +2723,7 @@ obj_sanity_check(void)
 static void
 objlist_sanity(struct obj *objlist, int wheretype, const char *mesg)
 {
-    struct obj *obj, *otmp;
+    struct obj *obj;
-    struct monst *shkp;
-    boolean costly;
-    const char *why;
 
     for (obj = objlist; obj; obj = obj->nobj) {
         if (obj->where != wheretype)
@@ -2737,50 +2735,9 @@ objlist_sanity(struct obj *objlist, int wheretype, const char *mesg)
                               mesg, (struct monst *) 0);
             check_contained(obj, mesg);
         }
-        why = (const char *) 0;
+        if (obj->unpaid || obj->no_charge) {
-        if (obj->no_charge && obj->unpaid) {
+            shop_obj_sanity(obj, mesg);
-            why = "%s obj both unpaid and no_charge! %s %s: %s";
+        }
-        } else if (obj->unpaid) {
-            /* unpaid is only applicable for directly carried objects and
-               for objects inside carried containers */
-            otmp = obj;
-            while (otmp->where == OBJ_CONTAINED)
-                otmp = otmp->ocontainer;
-            if (otmp != obj)
-                obj->ox = otmp->ox, obj->oy = otmp->oy;
-
-            if (otmp->where != OBJ_INVENT)
-                why = "%s unpaid obj not carried! %s %s: %s";
-            else if ((costly = costly_spot(obj->ox, obj->oy)) == FALSE)
-                why = "%s unpaid obj not inside shop! %s %s: %s";
-            else if ((shkp = shop_keeper(*in_rooms(obj->ox, obj->oy,
-                                                   SHOPBASE))) == 0)
-                why = "%s unpaid obj inside untended shop! %s %s: %s";
-            else if (!onshopbill(obj, shkp, TRUE))
-                why = "%s unpaid obj not on shop bill! %s %s: %s";
-        } else if (obj->no_charge) {
-            /* no_charge is only applicable for floor objects in shops and
-               for objects inside floor containers in shops */
-            otmp = obj;
-            while (otmp->where == OBJ_CONTAINED)
-                otmp = otmp->ocontainer;
-            if (otmp != obj)
-                (void) get_obj_location(otmp, &obj->ox, &obj->oy, BURIED_TOO);
-
-            if (otmp->where != OBJ_FLOOR)
-                why = "%s no_charge obj not on floor! %s %s: %s";
-            else if ((costly = costly_spot(obj->ox, obj->oy)) == FALSE)
-                why = "%s no_charge obj not inside shop! %s %s: %s";
-            else if ((shkp = shop_keeper(*in_rooms(obj->ox, obj->oy,
-                                                   SHOPBASE))) == 0)
-                why = "%s no_charge obj inside untended shop! %s %s: %s";
-            else if (onshopbill(obj, shkp, TRUE))
-                why = "%s no_charge obj on shop bill! %s %s: %s";
-            if (why)
-                insane_object(obj, why, mesg, (struct monst *) 0);
-        } /* unpaid and/or no_charge */
-        if (why)
-            insane_object(obj, why, mesg, (struct monst *) 0);
         if (obj->owornmask) {
             char maskbuf[40];
             boolean bc_ok = FALSE;
@@ -2819,6 +2776,63 @@ objlist_sanity(struct obj *objlist, int wheretype, const char *mesg)
     }
 }
 
+/* check obj->unpaid and obj->no_charge for shop sanity; caller has
+   verified that at least one of them is set */
+static void
+shop_obj_sanity(struct obj *obj, const char *mesg)
+{
+    struct obj *otop;
+    struct monst *shkp;
+    const char *why;
+    boolean costly;
+    coordxy x = 0, y = 0;
+
+    /* if contained, get top-most container; we needs its location */
+    otop = obj;
+    while (otop->where == OBJ_CONTAINED)
+        otop = otop->ocontainer;
+    /* get obj's or its container's location; do not update obj->ox,oy
+       or otop->ox,oy because that would cause sanity checking to
+       produce side-effects that won't occur when not sanity checking;
+       no need for CONTAINED_TOO because we have a top level container */
+    (void) get_obj_location(otop, &x, &y, BURIED_TOO);
+
+    /* these will always be needed for the normal case, so don't bother
+       waiting until we find an insanity to fetch them */
+    shkp = find_objowner(obj, x, y);
+    costly = costly_spot(x, y) || costly_adjacent(shkp, x, y);
+
+    why = (const char *) 0;
+    if (obj->no_charge && obj->unpaid) {
+        why = "%s obj both unpaid and no_charge! %s %s: %s";
+    } else if (obj->unpaid) {
+        /* unpaid is only applicable for directly carried objects and
+           for objects inside carried containers */
+        if (otop->where != OBJ_INVENT)
+            why = "%s unpaid obj not carried! %s %s: %s";
+        else if (!costly)
+            why = "%s unpaid obj not inside tended shop! %s %s: %s";
+        else if (!shkp)
+            why = "%s unpaid obj inside untended shop! %s %s: %s";
+        else if (!onshopbill(obj, shkp, TRUE))
+            why = "%s unpaid obj not on shop bill! %s %s: %s";
+    } else if (obj->no_charge) {
+        /* no_charge is only applicable for floor objects in shops
+           and for objects inside floor containers in shops */
+        if (otop->where != OBJ_FLOOR)
+            why = "%s no_charge obj not on floor! %s %s: %s";
+        else if (!costly)
+            why = "%s no_charge obj not inside tended shop! %s %s: %s";
+        else if (!shkp)
+            why = "%s no_charge obj inside untended shop! %s %s: %s";
+        else if (onshopbill(obj, shkp, TRUE))
+            why = "%s no_charge obj on shop bill! %s %s: %s";
+    }
+    if (why)
+        insane_object(obj, why, mesg, (struct monst *) 0);
+    return;
+}
+
 /* sanity check for objects carried by all monsters in specified list */
 static void
 mon_obj_sanity(struct monst *monlist, const char *mesg)

src/shk.c

@@ -862,6 +862,32 @@ shop_keeper(char rmno)
     return shkp;
 }
 
+/* find the shopkeeper who owns 'obj'; needed to handle shared shop walls */
+struct monst *
+find_objowner(
+    struct obj *obj,
+    coordxy x, coordxy y) /* caller passes obj's location since obj->ox,oy
+                           * might be stale; don't update coordinates here
+                           * because if we're called duing sanity checking
+                           * they shouldn't be modified */
+{
+    struct monst *shkp, *deflt_shkp = 0;
+    char *roomindx, *where = in_rooms(x, y, SHOPBASE);
+
+    /* conceptually object could be inside up to four rooms simultaneously;
+       in practice it will usually be one room but can sometimes be two;
+       check shk and bill for each room rather than just the first;
+       fallback to the first shk if obj isn't on the relevant bill(s) */
+    for (roomindx = where; *roomindx; ++roomindx)
+        if ((shkp = shop_keeper(*roomindx)) != 0) {
+            if (onshopbill(obj, shkp, TRUE))
+                return shkp;
+            if (!deflt_shkp)
+                deflt_shkp = shkp;
+        }
+    return deflt_shkp;
+}
+
 boolean
 tended_shop(struct mkroom *sroom)
 {
@@ -4384,7 +4410,7 @@ pay_for_damage(const char* dmgstr, boolean cant_mollify)
 
 /* called in dokick.c when we kick an object that might be in a store */
 boolean
-costly_spot(register coordxy x, register coordxy y)
+costly_spot(coordxy x, coordxy y)
 {
     struct monst *shkp;
     struct eshk *eshkp;
@@ -4399,6 +4425,24 @@ costly_spot(register coordxy x, register coordxy y)
                        && !(x == eshkp->shk.x && y == eshkp->shk.y));
 }
 
+/* called by sanity checking when an unpaid or no_charge item is not at a
+   costly_spot; it might still be within the boundary of the shop; if so,
+   those flags are still valid */
+boolean
+costly_adjacent(
+    struct monst *shkp,
+    coordxy x, coordxy y)
+{
+    struct eshk *eshkp;
+
+    if (!shkp || !inhishop(shkp) || !isok(x, y))
+        return FALSE;
+    eshkp = ESHK(shkp);
+    /* adjacent if <x,y> is a shop wall spot, including door;
+       also treat "free spot" one step inside the door as adjacent */
+    return (levl[x][y].edge || (x == eshkp->shk.x && y == eshkp->shk.y));
+}
+
 /* called by dotalk(sounds.c) when #chatting; returns obj if location
    contains shop goods and shopkeeper is willing & able to speak */
 struct obj *