udhcp: abort if we see unknown option, and show valid options if so

function                                             old     new   delta
udhcp_option_idx                                       -      77     +77
udhcp_str2optset                                     366     351     -15
udhcpc_main                                         2845    2801     -44
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 0/2 up/down: 77/-59)             Total: 18 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 3 insertions, 7 deletions

diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
index 478ca5c21..c36d4180b 100644
--- a/networking/udhcp/dhcpc.c
+++ b/networking/udhcp/dhcpc.c
@@ -879,21 +879,17 @@ int udhcpc_main(int argc UNUSED_PARAM, char **argv)
                 client_config.no_default_options = 1;
         while (list_O) {
                 char *optstr = llist_pop(&list_O);
-                int n = index_in_strings(dhcp_option_strings, optstr);
-                if (n < 0)
-                        bb_error_msg_and_die("unknown option '%s'", optstr);
+                unsigned n = udhcp_option_idx(optstr);
                 n = dhcp_options[n].code;
                 client_config.opt_mask[n >> 3] |= 1 << (n & 7);
         }
         while (list_x) {
-                int n;
+                unsigned n;
                 char *optstr = llist_pop(&list_x);
                 char *colon = strchr(optstr, ':');
                 if (colon)
                         *colon = '\0';
-                n = index_in_strings(dhcp_option_strings, optstr);
-                if (n < 0)
-                        bb_error_msg_and_die("unknown option '%s'", optstr);
+                n = udhcp_option_idx(optstr);
                 if (colon)
                         *colon = ' ';
                 udhcp_str2optset(optstr, &client_config.options);