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

2 files changed, 5 insertions, 5 deletions

diff --git a/loginutils/login.c b/loginutils/login.c
index a18b4d5d7..af871436a 100644
--- a/loginutils/login.c
+++ b/loginutils/login.c
@@ -275,7 +275,7 @@ int login_main(int argc UNUSED_PARAM, char **argv)
         if (!isatty(0) || !isatty(1) || !isatty(2))
                 return EXIT_FAILURE;            /* Must be a terminal */
         safe_strncpy(full_tty, "UNKNOWN", sizeof(full_tty));
-        tmp = ttyname(0);
+        tmp = xmalloc_ttyname(STDIN_FILENO);
         if (tmp) {
                 safe_strncpy(full_tty, tmp, sizeof(full_tty));
                 if (strncmp(full_tty, "/dev/", 5) == 0)
@@ -285,12 +285,12 @@ int login_main(int argc UNUSED_PARAM, char **argv)
         read_or_build_utent(&utent, run_by_root);
 
         if (opt & LOGIN_OPT_h) {
-                USE_FEATURE_UTMP(
+                if (ENABLE_FEATURE_UTMP)
                         safe_strncpy(utent.ut_host, opt_host, sizeof(utent.ut_host));
-                )
                 fromhost = xasprintf(" on '%s' from '%s'", short_tty, opt_host);
-        } else
+        } else {
                 fromhost = xasprintf(" on '%s'", short_tty);
+        }
 
         /* Was breaking "login <username>" from shell command line: */
         /*bb_setpgrp();*/
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);
         }