[src/trunk]: src/tests/lib/libc/sys Don't rely on INT_MAX being unmapped. Us...

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

details:   https://anonhg.NetBSD.org/src/rev/bab123f458a9
branches:  trunk
changeset: 778098:bab123f458a9
user:      matt <matt%NetBSD.org@localhost>
date:      Fri Mar 16 06:15:17 2012 +0000

description:
Don't rely on INT_MAX being unmapped.  Use mmap to get a page and then unmap
it.  Then use that address for msync.

diffstat:

 tests/lib/libc/sys/t_msync.c |  17 ++++++++++++++---
 1 files changed, 14 insertions(+), 3 deletions(-)

diffs (45 lines):

diff -r 13818a245ff7 -r bab123f458a9 tests/lib/libc/sys/t_msync.c
--- a/tests/lib/libc/sys/t_msync.c      Fri Mar 16 05:43:09 2012 +0000
+++ b/tests/lib/libc/sys/t_msync.c      Fri Mar 16 06:15:17 2012 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: t_msync.c,v 1.1 2011/07/07 06:57:54 jruoho Exp $ */
+/* $NetBSD: t_msync.c,v 1.2 2012/03/16 06:15:17 matt Exp $ */
 
 /*-
  * Copyright (c) 2011 The NetBSD Foundation, Inc.
@@ -29,7 +29,7 @@
  * POSSIBILITY OF SUCH DAMAGE.
  */
 #include <sys/cdefs.h>
-__RCSID("$NetBSD: t_msync.c,v 1.1 2011/07/07 06:57:54 jruoho Exp $");
+__RCSID("$NetBSD: t_msync.c,v 1.2 2012/03/16 06:15:17 matt Exp $");
 
 #include <sys/mman.h>
 
@@ -165,6 +165,8 @@
 ATF_TC_BODY(msync_err, tc)
 {
 
+       char *map = MAP_FAILED;
+
        /*
         * Test that invalid flags error out.
         */
@@ -173,7 +175,16 @@
 
        errno = 0;
 
-       ATF_REQUIRE(msync((void *)INT_MAX, page, MS_SYNC) != 0);
+       /*
+        * Map a page and then unmap to get an unmapped address.
+        */
+       map = mmap(NULL, page, PROT_READ | PROT_WRITE, MAP_ANON | MAP_PRIVATE,
+           -1, 0);
+       ATF_REQUIRE(map != MAP_FAILED);
+
+       (void)munmap(map, page);
+
+       ATF_REQUIRE(msync(map, page, MS_SYNC) != 0);
        ATF_REQUIRE(errno == EFAULT);
 }