top: add -m ("memory") option
[oweals/busybox.git] / loginutils / su.c
index e7e0001c73c996a2c2de4e8d8f704c8045bf1bfc..a3f7ed8a08a24f7e883376e4ae381edae870a6ae 100644 (file)
@@ -40,11 +40,24 @@ int su_main(int argc UNUSED_PARAM, char **argv)
 
        if (ENABLE_FEATURE_SU_SYSLOG) {
                /* The utmp entry (via getlogin) is probably the best way to identify
-               the user, especially if someone su's from a su-shell.
-               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";
+                * the user, especially if someone su's from a su-shell.
+                * But getlogin can fail -- usually due to lack of utmp entry.
+                * in this case resort to getpwuid.  */
+               const char *user;
+#if ENABLE_FEATURE_UTMP
+               char user_buf[64];
+               user = user_buf;
+               if (getlogin_r(user_buf, sizeof(user_buf)) != 0)
+#endif
+               {
+                       pw = getpwuid(cur_uid);
+                       user = pw ? pw->pw_name : "";
+               }
+               old_user = xstrdup(user);
+               tty = xmalloc_ttyname(2);
+               if (!tty) {
+                       tty = "none";
+               }
                openlog(applet_name, 0, LOG_AUTH);
        }
 
@@ -91,7 +104,7 @@ int su_main(int argc UNUSED_PARAM, char **argv)
        change_identity(pw);
        /* setup_environment params: shell, clear_env, change_env, pw */
        setup_environment(opt_shell, flags & SU_OPT_l, !(flags & SU_OPT_mp), pw);
-       USE_SELINUX(set_current_security_context(NULL);)
+       IF_SELINUX(set_current_security_context(NULL);)
 
        /* Never returns */
        run_shell(opt_shell, flags & SU_OPT_l, opt_command, (const char**)argv);