ll_map: disable interface name caching code

function                                             old     new   delta
find_by_index                                          -      26     +26
static.icache                                          4       -      -4
ll_idx_n2a                                            71      59     -12
static.ncache                                         16       -     -16
ll_index_to_flags                                     40      24     -16
xll_name_to_index                                    206     104    -102
------------------------------------------------------------------------------
(add/remove: 1/2 grow/shrink: 0/3 up/down: 26/-150)          Total: -124 bytes

   text    data     bss     dec     hex filename
 734703    3040   14440  752183   b7a37 busybox_old
 734599    3040   14416  752055   b79b7 busybox_unstripped

networking/libiproute/ll_map.c

@@ -11,9 +11,7 @@
  *
  */
 
-//#include <sys/socket.h>	/* socket() */
 #include <net/if.h>	/* struct ifreq and co. */
-//#include <sys/ioctl.h>	/* ioctl() & SIOCGIFINDEX */
 
 #include "libbb.h"
 #include "libnetlink.h"
@@ -31,6 +29,16 @@ struct idxmap {
 
 static struct idxmap *idxmap[16];
 
+static struct idxmap *find_by_index(int idx)
+{
+	struct idxmap *im;
+
+	for (im = idxmap[idx & 0xF]; im; im = im->next)
+		if (im->index == idx)
+			return im;
+	return NULL;
+}
+
 int ll_remember_index(struct sockaddr_nl *who, struct nlmsghdr *n, void *arg)
 {
 	int h;
@@ -44,7 +52,6 @@ int ll_remember_index(struct sockaddr_nl *who, struct nlmsghdr *n, void *arg)
 	if (n->nlmsg_len < NLMSG_LENGTH(sizeof(ifi)))
 		return -1;
 
-
 	memset(tb, 0, sizeof(tb));
 	parse_rtattr(tb, IFLA_MAX, IFLA_RTA(ifi), IFLA_PAYLOAD(n));
 	if (tb[IFLA_IFNAME] == NULL)
@@ -54,15 +61,13 @@ int ll_remember_index(struct sockaddr_nl *who, struct nlmsghdr *n, void *arg)
 
 	for (imp = &idxmap[h]; (im = *imp) != NULL; imp = &im->next)
 		if (im->index == ifi->ifi_index)
-			break;
+			goto found;
 
-	if (im == NULL) {
 	im = xmalloc(sizeof(*im));
 	im->next = *imp;
 	im->index = ifi->ifi_index;
 	*imp = im;
-	}
+ found:
-
 	im->type = ifi->ifi_type;
 	im->flags = ifi->ifi_flags;
 	if (tb[IFLA_ADDRESS]) {
@@ -85,8 +90,8 @@ const char *ll_idx_n2a(int idx, char *buf)
 
 	if (idx == 0)
 		return "*";
-	for (im = idxmap[idx & 0xF]; im; im = im->next)
+	im = find_by_index(idx);
-		if (im->index == idx)
+	if (im)
 		return im->name;
 	snprintf(buf, 16, "if%d", idx);
 	return buf;
@@ -100,17 +105,19 @@ const char *ll_index_to_name(int idx)
 	return ll_idx_n2a(idx, nbuf);
 }
 
+#ifdef UNUSED
 int ll_index_to_type(int idx)
 {
 	struct idxmap *im;
 
 	if (idx == 0)
 		return -1;
-	for (im = idxmap[idx & 0xF]; im; im = im->next)
+	im = find_by_index(idx);
-		if (im->index == idx)
+	if (im)
 		return im->type;
 	return -1;
 }
+#endif
 
 unsigned ll_index_to_flags(int idx)
 {
@@ -118,23 +125,24 @@ unsigned ll_index_to_flags(int idx)
 
 	if (idx == 0)
 		return 0;
-
+	im = find_by_index(idx);
-	for (im = idxmap[idx & 0xF]; im; im = im->next)
+	if (im)
-		if (im->index == idx)
 		return im->flags;
 	return 0;
 }
 
-// TODO: caching is not warranted - no users which repeatedly call it
 int xll_name_to_index(const char * const name)
 {
+	int ret = 0;
+	int sock_fd;
+
+/* caching is not warranted - no users which repeatedly call it */
+#ifdef UNUSED
 	static char ncache[16];
 	static int icache;
 
 	struct idxmap *im;
-	int sock_fd;
 	int i;
-	int ret = 0;
 
 	if (name == NULL)
 		goto out;
@@ -159,10 +167,13 @@ int xll_name_to_index(const char * const name)
 	 * we explicitely request it (check for dev_load() in net/core/dev.c).
 	 * I can think of other similar scenario, but they are less common...
 	 * Jean II */
+#endif
+
 	sock_fd = socket(AF_INET, SOCK_DGRAM, 0);
 	if (sock_fd) {
 		struct ifreq ifr;
 		int tmp;
+
 		strncpy(ifr.ifr_name, name, IFNAMSIZ);
 		ifr.ifr_ifindex = -1;
 		tmp = ioctl(sock_fd, SIOCGIFINDEX, &ifr);
@@ -173,7 +184,7 @@ int xll_name_to_index(const char * const name)
 			 * to the reader... Jean II */
 			ret = ifr.ifr_ifindex;
 	}
-out:
+/* out:*/
 	if (ret <= 0)
 		bb_error_msg_and_die("cannot find device \"%s\"", name);
 	return ret;

networking/libiproute/ll_map.h

@@ -2,12 +2,12 @@
 #ifndef __LL_MAP_H__
 #define __LL_MAP_H__ 1
 
-extern int ll_remember_index(struct sockaddr_nl *who, struct nlmsghdr *n, void *arg);
+int ll_remember_index(struct sockaddr_nl *who, struct nlmsghdr *n, void *arg);
-extern int ll_init_map(struct rtnl_handle *rth);
+int ll_init_map(struct rtnl_handle *rth);
-extern int xll_name_to_index(const char * const name);
+int xll_name_to_index(const char * const name);
-extern const char *ll_index_to_name(int idx);
+const char *ll_index_to_name(int idx);
-extern const char *ll_idx_n2a(int idx, char *buf);
+const char *ll_idx_n2a(int idx, char *buf);
-extern int ll_index_to_type(int idx);
+/* int ll_index_to_type(int idx); */
-extern unsigned ll_index_to_flags(int idx);
+unsigned ll_index_to_flags(int idx);
 
 #endif /* __LL_MAP_H__ */