Fix the makemon random coord picking again

This time try random locations up to 50 times, then start going
through the map in order to find a good position. First round
tries to pick a location not in sight, if that fails, it might
try stair or ladder location. If that fails, then it will pick
any good position, whether in sight or not.

Outside field of vision restriction and trying stair or ladder
locations does not happen when the monster is placed from special
level code.

src/makemon.c

@@ -944,6 +944,68 @@ newmextra()
     return mextra;
 }
 
+
+boolean
+makemon_rnd_goodpos(mon, gpflags, cc)
+struct monst *mon;
+unsigned gpflags;
+coord *cc;
+{
+    int tryct = 0;
+    int nx,ny;
+    boolean good;
+    do {
+        nx = rn1(COLNO - 3, 2);
+        ny = rn2(ROWNO);
+        if (!in_mklev && cansee(nx,ny)) good = FALSE;
+        else good = goodpos(nx, ny, mon, gpflags);
+    } while ((++tryct < 50) && !good);
+    if (!good) {
+        /* else go through all map positions, twice, first round
+           ignoring positions in sight, and pick first good one.
+           skip first round if we're in special level loader or blind */
+        int xofs = nx;
+        int yofs = ny;
+        int dx,dy;
+        int bl = (in_mklev || Blind) ? 1 : 0;
+        for ( ; bl < 2; bl++) {
+            for (dx = 0; dx < COLNO; dx++)
+                for (dy = 0; dy < ROWNO; dy++) {
+                    nx = ((dx + xofs) % (COLNO - 1)) + 1;
+                    ny = ((dy + yofs) % (ROWNO - 1)) + 1;
+                    if ((bl == 0) && cansee(nx,ny)) continue;
+                    if (goodpos(nx, ny, mon, gpflags))
+                        goto gotgood;
+                }
+            if (bl == 0 && (!mon || mon->data->mmove)) {
+                /* all map positions are visible (or not good),
+                   try to pick something logical */
+                if (dnstair.sx && !rn2(2)) {
+                    nx = dnstair.sx;
+                    ny = dnstair.sy;
+                } else if (upstair.sx && !rn2(2)) {
+                    nx = upstair.sx;
+                    ny = upstair.sy;
+                } else if (dnladder.sx && !rn2(2)) {
+                    nx = dnladder.sx;
+                    ny = dnladder.sy;
+                } else if (upladder.sx && !rn2(2)) {
+                    nx = upladder.sx;
+                    ny = upladder.sy;
+                }
+                if (goodpos(nx, ny, mon, gpflags))
+                    goto gotgood;
+            }
+        }
+    } else {
+    gotgood:
+        cc->x = nx;
+        cc->y = ny;
+        return TRUE;
+    }
+    return FALSE;
+}
+
 /*
  * called with [x,y] = coordinates;
  *	[0,0] means anyplace
@@ -967,19 +1029,14 @@ register int mmflags;
 
     /* if caller wants random location, do it here */
     if (x == 0 && y == 0) {
-        int tryct = 200; /* careful with bigrooms */
+        coord cc;
-        boolean good;
         struct monst fakemon;
 
         fakemon.data = ptr; /* set up for goodpos */
-        do {
+        if (!makemon_rnd_goodpos(ptr ? &fakemon : (struct monst *)0, gpflags, &cc))
-            x = rn1(COLNO - 3, 2);
-            y = rn2(ROWNO);
-            if (!in_mklev && cansee(x,y)) tryct--;
-            good = goodpos(x, y, ptr ? &fakemon : (struct monst *) 0, gpflags);
-        } while (tryct && !good);
-        if (!good)
             return ((struct monst *) 0);
+        x = cc.x;
+        y = cc.y;
     } else if (byyou && !in_mklev) {
         coord bypos;