Shop door entrance placement

If for some reason a shop room has multiple doors, try all of them
to find a good shop door, instead of just the first one, and failing
if it wasn't a good one.

This only matters for wizard-mode with SHOPTYPE environment var.

src/shknam.c

@@ -13,6 +13,7 @@ static int shkveg(void);
 static void mkveggy_at(int, int);
 static void mkshobj_at(const struct shclass *, int, int, boolean);
 static void nameshk(struct monst *, const char *const *);
+static int good_shopdoor(struct mkroom *, coordxy *, coordxy *);
 static int shkinit(const struct shclass *, struct mkroom *);
 
 #define VEGETARIAN_CLASS (MAXOCLASSES + 1)
@@ -569,47 +570,66 @@ free_eshk(struct monst* mtmp)
     mtmp->isshk = 0;
 }
 
+/* find a door in room sroom which is good for shop entrance.
+   returns -1 if no good door found, or the gd.doors index
+   and the door coordinates in sx, sy */
+static int
+good_shopdoor(struct mkroom *sroom, coordxy *sx, coordxy *sy)
+{
+    int i;
+
+    for (i = 0; i < sroom->doorct; i++) {
+        int di = sroom->fdoor + i;
+
+        *sx = gd.doors[di].x;
+        *sy = gd.doors[di].y;
+
+        /* check that the shopkeeper placement is sane */
+        if (sroom->irregular) {
+            int rmno = (int) ((sroom - gr.rooms) + ROOMOFFSET);
+
+            if (isok(*sx - 1, *sy) && !levl[*sx - 1][*sy].edge
+                && (int) levl[*sx - 1][*sy].roomno == rmno)
+                (*sx)--;
+            else if (isok(*sx + 1, *sy) && !levl[*sx + 1][*sy].edge
+                     && (int) levl[*sx + 1][*sy].roomno == rmno)
+                (*sx)++;
+            else if (isok(*sx, *sy - 1) && !levl[*sx][*sy - 1].edge
+                     && (int) levl[*sx][*sy - 1].roomno == rmno)
+                (*sy)--;
+            else if (isok(*sx, *sy + 1) && !levl[*sx][*sy + 1].edge
+                     && (int) levl[*sx][*sy + 1].roomno == rmno)
+                (*sy)++;
+            else
+                continue;
+        } else if (*sx == sroom->lx - 1) {
+            (*sx)++;
+        } else if (*sx == sroom->hx + 1) {
+            (*sx)--;
+        } else if (*sy == sroom->ly - 1) {
+            (*sy)++;
+        } else if (*sy == sroom->hy + 1) {
+            (*sy)--;
+        } else {
+            continue;
+        }
+        return di;
+    }
+    return -1;
+}
+
 /* create a new shopkeeper in the given room */
 static int
 shkinit(const struct shclass* shp, struct mkroom* sroom)
 {
-    register int sh, sx, sy;
+    int sh;
+    coordxy sx, sy;
     struct monst *shk;
     struct eshk *eshkp;
 
     /* place the shopkeeper in the given room */
-    sh = sroom->fdoor;
+    sh = good_shopdoor(sroom, &sx, &sy);
-    sx = gd.doors[sh].x;
+    if (sh < 0) {
-    sy = gd.doors[sh].y;
-
-    /* check that the shopkeeper placement is sane */
-    if (sroom->irregular) {
-        int rmno = (int) ((sroom - gr.rooms) + ROOMOFFSET);
-
-        if (isok(sx - 1, sy) && !levl[sx - 1][sy].edge
-            && (int) levl[sx - 1][sy].roomno == rmno)
-            sx--;
-        else if (isok(sx + 1, sy) && !levl[sx + 1][sy].edge
-                 && (int) levl[sx + 1][sy].roomno == rmno)
-            sx++;
-        else if (isok(sx, sy - 1) && !levl[sx][sy - 1].edge
-                 && (int) levl[sx][sy - 1].roomno == rmno)
-            sy--;
-        else if (isok(sx, sy + 1) && !levl[sx][sy + 1].edge
-                 && (int) levl[sx][sy + 1].roomno == rmno)
-            sy++;
-        else
-            goto shk_failed;
-    } else if (sx == sroom->lx - 1) {
-        sx++;
-    } else if (sx == sroom->hx + 1) {
-        sx--;
-    } else if (sy == sroom->ly - 1) {
-        sy++;
-    } else if (sy == sroom->hy + 1) {
-        sy--;
-    } else {
- shk_failed:
 #ifdef DEBUG
         /* Said to happen sometimes, but I have never seen it. */
         /* Supposedly fixed by fdoor change in mklev.c */