lib/util/util.c: move null-check before use

moves a null pointer check *before* the pointer is used in
the strlen() call

- still allocate the `fname` array on the stack
- still compiles under C90 definition/code mixing rules

Signed-off-by: Aurelien Aptel <aaptel@suse.com>
Reviewed-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Ralph Boehme <rb@sernet.de>

Autobuild-User(master): Jeremy Allison <jra@samba.org>
Autobuild-Date(master): Tue Mar  1 02:25:22 CET 2016 on sn-devel-144

1 files changed, 1 insertions, 5 deletions

diff --git a/lib/util/util.c b/lib/util/util.c
index 03edd7f7761..683741c60f7 100644
--- a/lib/util/util.c
+++ b/lib/util/util.c
@@ -66,15 +66,11 @@ _PUBLIC_ const char *tmpdir(void)
 **/
 int create_unlink_tmp(const char *dir)
 {
-	size_t len = strlen(dir);
+	size_t len = strlen(dir ? dir : (dir = tmpdir()));
 	char fname[len+25];
 	int fd;
 	mode_t mask;
 
-	if (!dir) {
-		dir = tmpdir();
-	}
-
 	len = snprintf(fname, sizeof(fname), "%s/listenerlock_XXXXXX", dir);
 	if (len >= sizeof(fname)) {
 		errno = ENOMEM;