ip: stop propagating argc; optimize ip_parse_common_args

function                                             old     new   delta
find_pair                                            167     187     +20
static.families                                        -      17     +17
die_must_be_on_off                                     -      11     +11
...
on_off                                                33      22     -11
do_ipaddr                                            103      90     -13
do_iptunnel                                         1001     986     -15
iproute_list_or_flush                               1237    1217     -20
static.ip_common_commands                             43      22     -21
do_iproute                                          2217    2193     -24
parse_args                                          1444    1414     -30
ip_do                                                 47      16     -31
do_iprule                                            994     963     -31
ip_main                                              153     113     -40
ipaddr_modify                                       1357    1305     -52
ipaddr_list_or_flush                                2543    2490     -53
ip_parse_common_args                                 294     159    -135
------------------------------------------------------------------------------
(add/remove: 4/1 grow/shrink: 4/24 up/down: 85/-563)         Total: -478 bytes
   text    data     bss     dec     hex filename
 775561     966    9236  785763   bfd63 busybox_old
 775073     962    9236  785271   bfb77 busybox_unstripped

1 files changed, 15 insertions, 22 deletions

diff --git a/networking/ip.c b/networking/ip.c
index 3ea1b62..182813d 100644
--- a/networking/ip.c
+++ b/networking/ip.c
@@ -24,57 +24,50 @@
  || ENABLE_FEATURE_IP_TUNNEL \
  || ENABLE_FEATURE_IP_RULE
 
-static int ATTRIBUTE_NORETURN ip_print_help(int ATTRIBUTE_UNUSED ac, char ATTRIBUTE_UNUSED **av)
+static int ATTRIBUTE_NORETURN ip_print_help(char ATTRIBUTE_UNUSED **argv)
 {
 	bb_show_usage();
 }
 
-static int (*ip_func)(int argc, char **argv) = ip_print_help;
-
-static int ip_do(int argc, char **argv)
+static int ip_do(int (*ip_func)(char **argv), char **argv)
 {
-	ip_parse_common_args(&argc, &argv);
-	return ip_func(argc-1, argv+1);
+	argv = ip_parse_common_args(argv);
+	return ip_func(argv);
 }
 
 #if ENABLE_FEATURE_IP_ADDRESS
 int ipaddr_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int ipaddr_main(int argc, char **argv)
 {
-    ip_func = do_ipaddr;
-    return ip_do(argc, argv);
+    return ip_do(do_ipaddr, argv);
 }
 #endif
 #if ENABLE_FEATURE_IP_LINK
 int iplink_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int iplink_main(int argc, char **argv)
 {
-    ip_func = do_iplink;
-    return ip_do(argc, argv);
+    return ip_do(do_iplink, argv);
 }
 #endif
 #if ENABLE_FEATURE_IP_ROUTE
 int iproute_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int iproute_main(int argc, char **argv)
 {
-    ip_func = do_iproute;
-    return ip_do(argc, argv);
+    return ip_do(do_iproute, argv);
 }
 #endif
 #if ENABLE_FEATURE_IP_RULE
 int iprule_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int iprule_main(int argc, char **argv)
 {
-    ip_func = do_iprule;
-    return ip_do(argc, argv);
+    return ip_do(do_iprule, argv);
 }
 #endif
 #if ENABLE_FEATURE_IP_TUNNEL
 int iptunnel_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int iptunnel_main(int argc, char **argv)
 {
-    ip_func = do_iptunnel;
-    return ip_do(argc, argv);
+    return ip_do(do_iptunnel, argv);
 }
 #endif
 
@@ -97,12 +90,12 @@ int ip_main(int argc, char **argv)
 		USE_FEATURE_IP_RULE(IP_rule,)
 		IP_none
 	};
+	int (*ip_func)(char **argv) = ip_print_help;
 
-	ip_parse_common_args(&argc, &argv);
-	if (argc > 1) {
-		int key = index_in_substrings(keywords, argv[1]);
-		argc -= 2;
-		argv += 2;
+	argv = ip_parse_common_args(argv + 1);
+	if (*argv) {
+		int key = index_in_substrings(keywords, *argv);
+		argv++;
 #if ENABLE_FEATURE_IP_ADDRESS
 		if (key == IP_addr)
 			ip_func = do_ipaddr;
@@ -124,7 +117,7 @@ int ip_main(int argc, char **argv)
 			ip_func = do_iprule;
 #endif
 	}
-	return ip_func(argc, argv);
+	return ip_func(argv);
 }
 
 #endif /* any of ENABLE_FEATURE_IP_xxx is 1 */