[src/trunk]: src/usr.bin/make make(1): in bmake_strndup, only scan the releva...

[rillig <rillig%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/0c3453a203ee
branches:  trunk
changeset: 1012841:0c3453a203ee
user:      rillig <rillig%NetBSD.org@localhost>
date:      Wed Aug 12 03:27:29 2020 +0000

description:
make(1): in bmake_strndup, only scan the relevant part of the string

Just in case the given str is not really a string.

The POSIX 2018 documentation on strndup does not specify as clearly as
possible whether s has to be a string or whether raw memory is
acceptable as well.  It only indirectly calls the s parameter of strndup
a string.

diffstat:

 usr.bin/make/make_malloc.c |  10 +++++-----
 1 files changed, 5 insertions(+), 5 deletions(-)

diffs (31 lines):

diff -r 861917e0b4d8 -r 0c3453a203ee usr.bin/make/make_malloc.c
--- a/usr.bin/make/make_malloc.c        Wed Aug 12 03:05:57 2020 +0000
+++ b/usr.bin/make/make_malloc.c        Wed Aug 12 03:27:29 2020 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: make_malloc.c,v 1.12 2020/07/03 08:02:55 rillig Exp $  */
+/*     $NetBSD: make_malloc.c,v 1.13 2020/08/12 03:27:29 rillig Exp $  */
 
 /*-
  * Copyright (c) 2009 The NetBSD Foundation, Inc.
@@ -28,7 +28,7 @@
 
 #ifdef MAKE_NATIVE
 #include <sys/cdefs.h>
-__RCSID("$NetBSD: make_malloc.c,v 1.12 2020/07/03 08:02:55 rillig Exp $");
+__RCSID("$NetBSD: make_malloc.c,v 1.13 2020/08/12 03:27:29 rillig Exp $");
 #endif
 
 #include <stdio.h>
@@ -95,9 +95,9 @@
        if (str == NULL)
                return NULL;
 
-       len = strlen(str);
-       if (len > max_len)
-               len = max_len;
+       for (len = 0; len < max_len; len++)
+           if (str[len] == '\0')
+               break;
        p = bmake_malloc(len + 1);
        memcpy(p, str, len);
        p[len] = '\0';