*: shrink: use Vladimir's "o+" specifier instead of xatou(opt_param)

function                                             old     new   delta
getopt32                                            1370    1385     +15
sulogin_main                                         490     494      +4
realpath_main                                         84      86      +2
sleep_main                                            76      77      +1
mt_main                                              256     257      +1
printenv_main                                         75      74      -1
fdformat_main                                        546     545      -1
usleep_main                                           44      42      -2
setlogcons_main                                       77      75      -2
ed_main                                             2654    2649      -5
deallocvt_main                                        69      64      -5
addgroup_main                                        373     368      -5
mkfs_minix_main                                     2989    2982      -7
tail_main                                           1221    1213      -8
sv_main                                             1254    1241     -13
du_main                                              348     328     -20
tftp_main                                            325     302     -23
split_main                                           581     558     -23
nc_main                                             1000     977     -23
diff_main                                            891     868     -23
arping_main                                         1797    1770     -27
ls_main                                              893     847     -46
od_main                                             2797    2750     -47
readprofile_main                                    1944    1895     -49
tcpudpsvd_main                                      1973    1922     -51
udhcpc_main                                         2590    2513     -77
grep_main                                            824     722    -102
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 5/22 up/down: 23/-560)         Total: -537 bytes
   text    data     bss     dec     hex filename
 796973     658    7428  805059   c48c3 busybox_old
 796479     662    7420  804561   c46d1 busybox_unstripped

3 files changed, 11 insertions, 11 deletions

diff --git a/loginutils/addgroup.c b/loginutils/addgroup.c
index 31e5070..b25f817 100644
--- a/loginutils/addgroup.c
+++ b/loginutils/addgroup.c
@@ -123,7 +123,7 @@ static void add_user_to_group(char **args,
  * will add an existing user to an existing group.
  */
 int addgroup_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-int addgroup_main(int argc, char **argv)
+int addgroup_main(int argc ATTRIBUTE_UNUSED, char **argv)
 {
 	char *group;
 	gid_t gid = 0;
@@ -144,10 +144,10 @@ int addgroup_main(int argc, char **argv)
 	}
 	/* move past the commandline options */
 	argv += optind;
-	argc -= optind;
+	//argc -= optind;
 
 #if ENABLE_FEATURE_ADDUSER_TO_GROUP
-	if (argc == 2) {
+	if (argv[1]) {
 		struct group *gr;
 
 		if (option_mask32) {
@@ -170,7 +170,7 @@ int addgroup_main(int argc, char **argv)
 		add_user_to_group(argv, bb_path_group_file, xfopen);
 #if ENABLE_FEATURE_SHADOWPASSWDS
 		add_user_to_group(argv, bb_path_gshadow_file, fopen_or_warn);
-#endif /* ENABLE_FEATURE_SHADOWPASSWDS */
+#endif
 	} else
 #endif /* ENABLE_FEATURE_ADDUSER_TO_GROUP */
 		new_group(argv[0], gid);
diff --git a/loginutils/login.c b/loginutils/login.c
index d7eb8d3..e8fe74e 100644
--- a/loginutils/login.c
+++ b/loginutils/login.c
@@ -221,7 +221,7 @@ static void alarm_handler(int sig ATTRIBUTE_UNUSED)
 }
 
 int login_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-int login_main(int argc, char **argv)
+int login_main(int argc ATTRIBUTE_UNUSED, char **argv)
 {
 	enum {
 		LOGIN_OPT_f = (1<<0),
@@ -269,8 +269,9 @@ int login_main(int argc, char **argv)
 			bb_error_msg_and_die("-f is for root only");
 		safe_strncpy(username, opt_user, sizeof(username));
 	}
-	if (optind < argc) /* user from command line (getty) */
-		safe_strncpy(username, argv[optind], sizeof(username));
+	argv += optind;
+	if (argv[0]) /* user from command line (getty) */
+		safe_strncpy(username, argv[0], sizeof(username));
 
 	/* Let's find out and memorize our tty */
 	if (!isatty(0) || !isatty(1) || !isatty(2))
diff --git a/loginutils/sulogin.c b/loginutils/sulogin.c
index caa1a83..17bb15e 100644
--- a/loginutils/sulogin.c
+++ b/loginutils/sulogin.c
@@ -19,7 +19,6 @@ int sulogin_main(int argc ATTRIBUTE_UNUSED, char **argv)
 {
 	char *cp;
 	int timeout = 0;
-	char *timeout_arg;
 	struct passwd *pwd;
 	const char *shell;
 #if ENABLE_FEATURE_SHADOWPASSWDS
@@ -31,9 +30,8 @@ int sulogin_main(int argc ATTRIBUTE_UNUSED, char **argv)
 	logmode = LOGMODE_BOTH;
 	openlog(applet_name, 0, LOG_AUTH);
 
-	if (getopt32(argv, "t:", &timeout_arg)) {
-		timeout = xatoi_u(timeout_arg);
-	}
+	opt_complementary = "t+"; /* -t N */
+	getopt32(argv, "t:", &timeout);
 
 	if (argv[optind]) {
 		close(0);
@@ -43,6 +41,7 @@ int sulogin_main(int argc ATTRIBUTE_UNUSED, char **argv)
 		dup(0);
 	}
 
+	/* Malicious use like "sulogin /dev/sda"? */
 	if (!isatty(0) || !isatty(1) || !isatty(2)) {
 		logmode = LOGMODE_SYSLOG;
 		bb_error_msg_and_die("not a tty");