setup_environment: code shrink

run_shell: mark as NORETURN
setup_environment, run_shell: add usage comments
login: add FIXME :(

function                                             old     new   delta
UNSPEC_print                                          64      66      +2
sulogin_main                                         509     506      -3
mkfs_minix_main                                     3070    3067      -3
login_main                                          1615    1612      -3
su_main                                              461     448     -13
setup_environment                                    261     206     -55
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/5 up/down: 2/-77)             Total: -75 bytes
   text    data     bss     dec     hex filename
 772578    1051   10724  784353   bf7e1 busybox_old
 772502    1051   10724  784277   bf795 busybox_unstripped

1 files changed, 5 insertions, 2 deletions

diff --git a/loginutils/login.c b/loginutils/login.c
index 5d5053840..7f8907543 100644
--- a/loginutils/login.c
+++ b/loginutils/login.c
@@ -432,7 +432,9 @@ int login_main(int argc, char **argv)
         tmp = pw->pw_shell;
         if (!tmp || !*tmp)
                 tmp = DEFAULT_SHELL;
+        /* setup_environment params: shell, loginshell, changeenv, pw */
         setup_environment(tmp, 1, !(opt & LOGIN_OPT_p), pw);
+        /* FIXME: login shell = 1 -> 3rd parameter is ignored! */
 
         motd();
 
@@ -463,7 +465,8 @@ int login_main(int argc, char **argv)
          * should it leave SIGINT etc enabled or disabled? */
         signal(SIGINT, SIG_DFL);
 
-        run_shell(tmp, 1, 0, 0);        /* exec the shell finally */
+        /* Exec login shell with no additional parameters */
+        run_shell(tmp, 1, NULL, NULL);
 
-        return EXIT_FAILURE;
+        /* return EXIT_FAILURE; - not reached */
 }