fish: remove modulo bias from random number generation

It probably doesn't matter in practice, but omitting this piece of code
always looks like an oversight.

diff --git a/fish/fish.c b/fish/fish.c
index 78e2dc528cf13203f1ec478dbce10fc8ce1876a8..36800d031a302e6a21f83f605917d37d6f40992b 100644 (file)
--- a/fish/fish.c
+++ b/fish/fish.c
@@ -1,4 +1,4 @@
-/*     $NetBSD: fish.c,v 1.23 2018/03/05 04:59:54 eadler Exp $ */
+/*     $NetBSD: fish.c,v 1.24 2021/05/01 21:10:57 rillig Exp $ */
 
 /*-
  * Copyright (c) 1990, 1993
@@ -42,7 +42,7 @@ __COPYRIGHT("@(#) Copyright (c) 1990, 1993\
 #if 0
 static char sccsid[] = "@(#)fish.c     8.1 (Berkeley) 5/31/93";
 #else
-__RCSID("$NetBSD: fish.c,v 1.23 2018/03/05 04:59:54 eadler Exp $");
+__RCSID("$NetBSD: fish.c,v 1.24 2021/05/01 21:10:57 rillig Exp $");
 #endif
 #endif /* not lint */
 
@@ -435,8 +435,13 @@ init(void)
 static int
 nrandom(int n)
 {
+       long r;
 
-       return((int)random() % n);
+       for (;;) {
+               r = random();
+               if (r < RANDOM_MAX - RANDOM_MAX % n)
+                       return (int)(r % n);
+       }
 }
 
 static void