networking/interface.c: reduce bss usage

function                                             old     new   delta
.rodata                                           158918  158950     +32
display_interfaces                                   133     153     +20
UNSPEC_print                                          56      68     +12
pr_ether                                              59      65      +6
static.proc_read                                       4       1      -3
interface_opt_a                                        4       1      -3
in_ether                                             139     136      -3
ifconfig_main                                       1296    1293      -3
if_readlist_proc                                     686     680      -6
ife_print                                           1350    1338     -12
do_if_print                                           46       -     -46
static.buff                                          369     264    -105
------------------------------------------------------------------------------
(add/remove: 0/1 grow/shrink: 4/7 up/down: 70/-181)          Total: -111 bytes

# size busybox_old busybox_unstripped
   text    data     bss     dec     hex filename
 751073    3080   14800  768953   bbbb9 busybox_old
 751073    3048   14688  768809   bbb29 busybox_unstripped

1 files changed, 54 insertions, 45 deletions

diff --git a/networking/interface.c b/networking/interface.c
index 51e3d7487..f8721f409 100644
--- a/networking/interface.c
+++ b/networking/interface.c
@@ -88,11 +88,9 @@ static const char *INET_sprint(struct sockaddr *sap, int numeric)
 
 	if (sap->sa_family == 0xFFFF || sap->sa_family == 0)
 		return "[NONE SET]";
-
 	if (INET_rresolve(buff, sizeof(buff), (struct sockaddr_in *) sap,
 					  numeric, 0xffffff00) != 0)
 		return NULL;
-
 	return buff;
 }
 
@@ -221,10 +219,13 @@ static const struct aftype inet6_aftype = {
 /* Display an UNSPEC address. */
 static char *UNSPEC_print(unsigned char *ptr)
 {
-	static char buff[sizeof(struct sockaddr) * 3 + 1];
+	static char *buff;
+
 	char *pos;
 	unsigned int i;
 
+	if (!buff);
+		buff = xmalloc(sizeof(struct sockaddr) * 3 + 1);
 	pos = buff;
 	for (i = 0; i < sizeof(struct sockaddr); i++) {
 		/* careful -- not every libc's sprintf returns # bytes written */
@@ -341,7 +342,7 @@ struct interface {
 };
 
 
-int interface_opt_a;	/* show all interfaces          */
+smallint interface_opt_a;	/* show all interfaces */
 
 static struct interface *int_list, *int_last;
 
@@ -522,7 +523,7 @@ static int if_readconf(void)
 		ifc.ifc_buf = xrealloc(ifc.ifc_buf, ifc.ifc_len);
 
 		if (ioctl(skfd, SIOCGIFCONF, &ifc) < 0) {
-			perror("SIOCGIFCONF");
+			bb_perror_msg("SIOCGIFCONF");
 			goto out;
 		}
 		if (ifc.ifc_len == sizeof(struct ifreq) * numreqs) {
@@ -548,7 +549,8 @@ static int if_readconf(void)
 
 static int if_readlist_proc(char *target)
 {
-	static int proc_read;
+	static smallint proc_read;
+
 	FILE *fh;
 	char buf[512];
 	struct interface *ife;
@@ -581,7 +583,7 @@ static int if_readlist_proc(char *target)
 			break;
 	}
 	if (ferror(fh)) {
-		perror(_PATH_PROCNET_DEV);
+		bb_perror_msg(_PATH_PROCNET_DEV);
 		err = -1;
 		proc_read = 0;
 	}
@@ -598,22 +600,6 @@ static int if_readlist(void)
 	return err;
 }
 
-static int for_all_interfaces(int (*doit) (struct interface *, void *),
-							  void *cookie)
-{
-	struct interface *ife;
-
-	if (!int_list && (if_readlist() < 0))
-		return -1;
-	for (ife = int_list; ife; ife = ife->next) {
-		int err = doit(ife, cookie);
-
-		if (err)
-			return err;
-	}
-	return 0;
-}
-
 /* Fetch the interface configuration from the kernel. */
 static int if_fetch(struct interface *ife)
 {
@@ -732,9 +718,10 @@ static const struct hwtype loop_hwtype = {
 /* Display an Ethernet address in readable format. */
 static char *pr_ether(unsigned char *ptr)
 {
-	static char buff[64];
+	static char *buff;
 
-	snprintf(buff, sizeof(buff), "%02X:%02X:%02X:%02X:%02X:%02X",
+	free(buff);
+	buff = xasprintf("%02X:%02X:%02X:%02X:%02X:%02X",
 			 (ptr[0] & 0377), (ptr[1] & 0377), (ptr[2] & 0377),
 			 (ptr[3] & 0377), (ptr[4] & 0377), (ptr[5] & 0377)
 		);
@@ -743,7 +730,7 @@ static char *pr_ether(unsigned char *ptr)
 
 static int in_ether(const char *bufp, struct sockaddr *sap);
 
-static struct hwtype ether_hwtype = {
+static const struct hwtype ether_hwtype = {
 	.name =		"ether",
 	.title =	"Ethernet",
 	.type =		ARPHRD_ETHER,
@@ -1040,29 +1027,28 @@ static void ife_print(struct interface *ptr)
 						  (struct sockaddr *) &sap.sin6_addr);
 				sap.sin6_family = AF_INET6;
 				printf("          inet6 addr: %s/%d",
-					   inet6_aftype.sprint((struct sockaddr *) &sap, 1),
+					   INET6_sprint((struct sockaddr *) &sap, 1),
 					   plen);
 				printf(" Scope:");
 				switch (scope & IPV6_ADDR_SCOPE_MASK) {
 				case 0:
-					printf("Global");
+					puts("Global");
 					break;
 				case IPV6_ADDR_LINKLOCAL:
-					printf("Link");
+					puts("Link");
 					break;
 				case IPV6_ADDR_SITELOCAL:
-					printf("Site");
+					puts("Site");
 					break;
 				case IPV6_ADDR_COMPATv4:
-					printf("Compat");
+					puts("Compat");
 					break;
 				case IPV6_ADDR_LOOPBACK:
-					printf("Host");
+					puts("Host");
 					break;
 				default:
-					printf("Unknown");
+					puts("Unknown");
 				}
-				puts("");
 			}
 		}
 		fclose(f);
@@ -1144,14 +1130,13 @@ static void ife_print(struct interface *ptr)
 }
 
 
-static int do_if_print(struct interface *ife, void *cookie)
+static int do_if_print(struct interface *ife) /*, int *opt_a)*/
 {
-	int *opt_a = (int *) cookie;
 	int res;
 
 	res = do_if_fetch(ife);
 	if (res >= 0) {
-		if ((ife->flags & IFF_UP) || *opt_a)
+		if ((ife->flags & IFF_UP) || interface_opt_a)
 			ife_print(ife);
 	}
 	return res;
@@ -1167,21 +1152,45 @@ static struct interface *lookup_interface(char *name)
 	return ife;
 }
 
+#ifdef UNUSED
+static int for_all_interfaces(int (*doit) (struct interface *, void *),
+							  void *cookie)
+{
+	struct interface *ife;
+
+	if (!int_list && (if_readlist() < 0))
+		return -1;
+	for (ife = int_list; ife; ife = ife->next) {
+		int err = doit(ife, cookie);
+
+		if (err)
+			return err;
+	}
+	return 0;
+}
+#endif
+
 /* for ipv4 add/del modes */
 static int if_print(char *ifname)
 {
+	struct interface *ife;
 	int res;
 
 	if (!ifname) {
-		res = for_all_interfaces(do_if_print, &interface_opt_a);
-	} else {
-		struct interface *ife;
-
-		ife = lookup_interface(ifname);
-		res = do_if_fetch(ife);
-		if (res >= 0)
-			ife_print(ife);
+		/*res = for_all_interfaces(do_if_print, &interface_opt_a);*/
+		if (!int_list && (if_readlist() < 0))
+			return -1;
+		for (ife = int_list; ife; ife = ife->next) {
+			int err = do_if_print(ife); /*, &interface_opt_a);*/
+			if (err)
+				return err;
+		}
+		return 0;
 	}
+	ife = lookup_interface(ifname);
+	res = do_if_fetch(ife);
+	if (res >= 0)
+		ife_print(ife);
 	return res;
 }