libbb: introduce and use xmalloc_ttyname (-32 in bss).

ash: small code shrink

   text    data     bss     dec     hex filename
 793669     504    7524  801697   c3ba1 busybox_old
 793659     504    7492  801655   c3b77 busybox_unstripped

1 files changed, 1 insertions, 1 deletions

diff --git a/loginutils/su.c b/loginutils/su.c
index e7e0001c7..de8c18d25 100644
--- a/loginutils/su.c
+++ b/loginutils/su.c
@@ -44,7 +44,7 @@ int su_main(int argc UNUSED_PARAM, char **argv)
                 But getlogin can fail -- usually due to lack of utmp entry.
                 in this case resort to getpwuid.  */
                 old_user = xstrdup(USE_FEATURE_UTMP(getlogin() ? : ) (pw = getpwuid(cur_uid)) ? pw->pw_name : "");
-                tty = ttyname(2) ? : "none";
+                tty = xmalloc_ttyname(2) ? : "none";
                 openlog(applet_name, 0, LOG_AUTH);
         }