libiproute: audit callgraph, shortcut error paths into die() functions.

Kill a few statics, made other globals smaller:
oneline is smallint, _SL_ is char

function                                             old     new   delta
print_tunnel                                         693     731     +38
print_route                                         1775    1777      +2
print_addrinfo                                      1495    1497      +2
ipaddr_list_or_flush                                2826    2828      +2
oneline                                                4       1      -3
_SL_                                                   4       1      -3
ipaddr_modify                                       1476    1472      -4
parse_address                                        124     119      -5
ip_parse_common_args                                 429     423      -6
on_off                                                53      46      -7
do_del_ioctl                                         113     106      -7
do_add_ioctl                                         120     113      -7
do_show                                              864     856      -8
iprule_list                                          157     148      -9
do_iptunnel                                          310     299     -11
do_add                                               143     126     -17
get_ctl_fd                                            95      76     -19
set_address                                          108      84     -24
ip_main                                              351     323     -28
static.ifr                                            32       -     -32
parse_args                                          1992    1949     -43
iproute_list_or_flush                               1673    1582     -91
do_iplink                                           1583    1485     -98
filter                                               280       -    -280
------------------------------------------------------------------------------
(add/remove: 0/2 grow/shrink: 4/18 up/down: 44/-702)         Total: -658 bytes

11 files changed, 247 insertions, 319 deletions

diff --git a/networking/ip.c b/networking/ip.c
index fdd8480..d516895 100644
--- a/networking/ip.c
+++ b/networking/ip.c
@@ -20,31 +20,28 @@
 int ip_main(int argc, char **argv);
 int ip_main(int argc, char **argv)
 {
-	int ret = EXIT_FAILURE;
-
 	ip_parse_common_args(&argc, &argv);
 
-	if (argc > 1) {
-		if (ENABLE_FEATURE_IP_ADDRESS && matches(argv[1], "address") == 0) {
-			ret = do_ipaddr(argc-2, argv+2);
-		}
-		if (ENABLE_FEATURE_IP_ROUTE && matches(argv[1], "route") == 0) {
-			ret = do_iproute(argc-2, argv+2);
-		}
-		if (ENABLE_FEATURE_IP_LINK && matches(argv[1], "link") == 0) {
-			ret = do_iplink(argc-2, argv+2);
-		}
-		if (ENABLE_FEATURE_IP_TUNNEL
-		 && (matches(argv[1], "tunnel") == 0 || strcmp(argv[1], "tunl") == 0)
-		) {
-			ret = do_iptunnel(argc-2, argv+2);
-		}
-		if (ENABLE_FEATURE_IP_RULE && matches(argv[1], "rule") == 0) {
-			ret = do_iprule(argc-2, argv+2);
-		}
-	}
-	if (ret) {
+	if (argc <= 1)
 		bb_show_usage();
+
+	if (ENABLE_FEATURE_IP_ADDRESS && matches(argv[1], "address") == 0) {
+		return do_ipaddr(argc-2, argv+2);
+	}
+	if (ENABLE_FEATURE_IP_ROUTE && matches(argv[1], "route") == 0) {
+		return do_iproute(argc-2, argv+2);
 	}
-	return EXIT_SUCCESS;
+	if (ENABLE_FEATURE_IP_LINK && matches(argv[1], "link") == 0) {
+		return do_iplink(argc-2, argv+2);
+	}
+	if (ENABLE_FEATURE_IP_TUNNEL
+	 && (matches(argv[1], "tunnel") == 0 || strcmp(argv[1], "tunl") == 0)
+	) {
+		return do_iptunnel(argc-2, argv+2);
+	}
+	if (ENABLE_FEATURE_IP_RULE && matches(argv[1], "rule") == 0) {
+		return do_iprule(argc-2, argv+2);
+	}
+
+	bb_show_usage();
 }
diff --git a/networking/libiproute/ip_common.h b/networking/libiproute/ip_common.h
index 05a6a95..96df610 100644
--- a/networking/libiproute/ip_common.h
+++ b/networking/libiproute/ip_common.h
@@ -13,16 +13,13 @@
 #include <linux/if_link.h>
 #endif
 
-extern int preferred_family;
-//FIXME! Appears in two .h files!
-extern const char * _SL_;
-
 extern void ip_parse_common_args(int *argcp, char ***argvp);
 extern int print_neigh(struct sockaddr_nl *who, struct nlmsghdr *n, void *arg);
 extern int ipaddr_list_or_flush(int argc, char **argv, int flush);
 extern int iproute_monitor(int argc, char **argv);
 extern void iplink_usage(void) ATTRIBUTE_NORETURN;
 extern void ipneigh_reset_filter(void);
+
 extern int do_ipaddr(int argc, char **argv);
 extern int do_iproute(int argc, char **argv);
 extern int do_iprule(int argc, char **argv);
diff --git a/networking/libiproute/ip_parse_common_args.c b/networking/libiproute/ip_parse_common_args.c
index 00a8912..6efbc69 100644
--- a/networking/libiproute/ip_parse_common_args.c
+++ b/networking/libiproute/ip_parse_common_args.c
@@ -23,8 +23,8 @@
 
 
 int preferred_family = AF_UNSPEC;
-int oneline = 0;
-const char * _SL_ = NULL;
+smallint oneline;
+char _SL_;
 
 void ip_parse_common_args(int *argcp, char ***argvp)
 {
@@ -73,7 +73,7 @@ void ip_parse_common_args(int *argcp, char ***argvp)
 		argc--;
 		argv++;
 	}
-	_SL_ = oneline ? "\\" : "\n" ;
+	_SL_ = oneline ? '\\' : '\n' ;
 	*argcp = argc;
 	*argvp = argv;
 }
diff --git a/networking/libiproute/ipaddress.c b/networking/libiproute/ipaddress.c
index bc9963f..ab97064 100644
--- a/networking/libiproute/ipaddress.c
+++ b/networking/libiproute/ipaddress.c
@@ -26,8 +26,7 @@
 #include "ip_common.h"
 
 
-static struct
-{
+typedef struct filter_t {
 	int ifindex;
 	int family;
 	int oneline;
@@ -42,7 +41,10 @@ static struct
 	int flushp;
 	int flushe;
 	struct rtnl_handle *rth;
-} filter;
+} filter_t;
+
+#define filter (*(filter_t*)&bb_common_bufsiz1)
+
 
 static void print_link_flags(FILE *fp, unsigned flags, unsigned mdown)
 {
@@ -88,7 +90,7 @@ static void print_queuelen(char *name)
 	memset(&ifr, 0, sizeof(ifr));
 	strncpy(ifr.ifr_name, name, sizeof(ifr.ifr_name));
 	if (ioctl(s, SIOCGIFTXQLEN, &ifr) < 0) {
-		perror("SIOCGIFXQLEN");
+		bb_perror_msg("SIOCGIFXQLEN");
 		close(s);
 		return;
 	}
@@ -125,10 +127,12 @@ static int print_linkinfo(struct sockaddr_nl ATTRIBUTE_UNUSED *who,
 		bb_error_msg("nil ifname");
 		return -1;
 	}
-	if (filter.label &&
-	    (!filter.family || filter.family == AF_PACKET) &&
-	    fnmatch(filter.label, RTA_DATA(tb[IFLA_IFNAME]), 0))
+	if (filter.label
+	 && (!filter.family || filter.family == AF_PACKET)
+	 && fnmatch(filter.label, RTA_DATA(tb[IFLA_IFNAME]), 0)
+	) {
 		return 0;
+	}
 
 	if (n->nlmsg_type == RTM_DELLINK)
 		fprintf(fp, "Deleted ");
@@ -166,8 +170,7 @@ static int print_linkinfo(struct sockaddr_nl ATTRIBUTE_UNUSED *who,
 
 	if (!filter.family || filter.family == AF_PACKET) {
 		SPRINT_BUF(b1);
-		fprintf(fp, "%s", _SL_);
-		fprintf(fp, "    link/%s ", ll_type_n2a(ifi->ifi_type, b1, sizeof(b1)));
+		fprintf(fp, "%c    link/%s ", _SL_, ll_type_n2a(ifi->ifi_type, b1, sizeof(b1)));
 
 		if (tb[IFLA_ADDRESS]) {
 			fprintf(fp, "%s", ll_addr_n2a(RTA_DATA(tb[IFLA_ADDRESS]),
@@ -186,7 +189,7 @@ static int print_linkinfo(struct sockaddr_nl ATTRIBUTE_UNUSED *who,
 						      b1, sizeof(b1)));
 		}
 	}
-	fprintf(fp, "\n");
+	fputc('\n', fp);
 	fflush(fp);
 	return 0;
 }
@@ -194,7 +197,7 @@ static int print_linkinfo(struct sockaddr_nl ATTRIBUTE_UNUSED *who,
 static int flush_update(void)
 {
 	if (rtnl_send(filter.rth, filter.flushb, filter.flushp) < 0) {
-		perror("Failed to send flush request\n");
+		bb_perror_msg("failed to send flush request");
 		return -1;
 	}
 	filter.flushp = 0;
@@ -341,7 +344,7 @@ static int print_addrinfo(struct sockaddr_nl ATTRIBUTE_UNUSED *who,
 	if (rta_tb[IFA_CACHEINFO]) {
 		struct ifa_cacheinfo *ci = RTA_DATA(rta_tb[IFA_CACHEINFO]);
 		char buf[128];
-		fprintf(fp, "%s", _SL_);
+		fputc(_SL_, fp);
 		if (ci->ifa_valid == 0xFFFFFFFFU)
 			sprintf(buf, "valid_lft forever");
 		else
@@ -352,7 +355,7 @@ static int print_addrinfo(struct sockaddr_nl ATTRIBUTE_UNUSED *who,
 			sprintf(buf+strlen(buf), " preferred_lft %dsec", ci->ifa_prefered);
 		fprintf(fp, "       %s", buf);
 	}
-	fprintf(fp, "\n");
+	fputc('\n', fp);
 	fflush(fp);
 	return 0;
 }
@@ -366,7 +369,7 @@ struct nlmsg_list
 
 static int print_selected_addrinfo(int ifindex, struct nlmsg_list *ainfo, FILE *fp)
 {
-	for ( ;ainfo ;  ainfo = ainfo->next) {
+	for (; ainfo; ainfo = ainfo->next) {
 		struct nlmsghdr *n = &ainfo->h;
 		struct ifaddrmsg *ifa = NLMSG_DATA(n);
 
@@ -412,6 +415,7 @@ static void ipaddr_reset_filter(int _oneline)
 	filter.oneline = _oneline;
 }
 
+/* Return value becomes exitcode. It's okay to not return at all */
 int ipaddr_list_or_flush(int argc, char **argv, int flush)
 {
 	static const char *const option[] = { "to", "scope", "up", "label", "dev", 0 };
@@ -431,12 +435,10 @@ int ipaddr_list_or_flush(int argc, char **argv, int flush)
 
 	if (flush) {
 		if (argc <= 0) {
-			bb_error_msg(bb_msg_requires_arg, "flush");
-			return -1;
+			bb_error_msg_and_die(bb_msg_requires_arg, "flush");
 		}
 		if (filter.family == AF_PACKET) {
-			bb_error_msg("cannot flush link addresses");
-			return -1;
+			bb_error_msg_and_die("cannot flush link addresses");
 		}
 	}
 
@@ -498,8 +500,7 @@ int ipaddr_list_or_flush(int argc, char **argv, int flush)
 	if (filter_dev) {
 		filter.ifindex = ll_name_to_index(filter_dev);
 		if (filter.ifindex <= 0) {
-			bb_error_msg("device \"%s\" does not exist", filter_dev);
-			return -1;
+			bb_error_msg_and_die("device \"%s\" does not exist", filter_dev);
 		}
 	}
 
@@ -513,20 +514,17 @@ int ipaddr_list_or_flush(int argc, char **argv, int flush)
 
 		for (;;) {
 			if (rtnl_wilddump_request(&rth, filter.family, RTM_GETADDR) < 0) {
-				perror("Cannot send dump request");
-				exit(1);
+				bb_perror_msg_and_die("cannot send dump request");
 			}
 			filter.flushed = 0;
 			if (rtnl_dump_filter(&rth, print_addrinfo, stdout, NULL, NULL) < 0) {
-				fprintf(stderr, "Flush terminated\n");
-				exit(1);
+				bb_error_msg_and_die("flush terminated");
 			}
 			if (filter.flushed == 0) {
-				fflush(stdout);
 				return 0;
 			}
 			if (flush_update() < 0)
-				exit(1);
+				return 1;
 		}
 	}
 
@@ -601,16 +599,16 @@ int ipaddr_list_or_flush(int argc, char **argv, int flush)
 		}
 	}
 
-	for (l=linfo; l; l = l->next) {
+	for (l = linfo; l; l = l->next) {
 		if (no_link || print_linkinfo(NULL, &l->h, stdout) == 0) {
 			struct ifinfomsg *ifi = NLMSG_DATA(&l->h);
 			if (filter.family != AF_PACKET)
 				print_selected_addrinfo(ifi->ifi_index, ainfo, stdout);
 		}
-		fflush(stdout);
+		fflush(stdout); /* why? */
 	}
 
-	exit(0);
+	return 0;
 }
 
 static int default_scope(inet_prefix *lcl)
@@ -622,6 +620,7 @@ static int default_scope(inet_prefix *lcl)
 	return 0;
 }
 
+/* Return value becomes exitcode. It's okay to not return at all */
 static int ipaddr_modify(int cmd, int argc, char **argv)
 {
 	static const char *const option[] = {
@@ -763,8 +762,7 @@ static int ipaddr_modify(int cmd, int argc, char **argv)
 		inet_prefix brd;
 		int i;
 		if (req.ifa.ifa_family != AF_INET) {
-			bb_error_msg("broadcast can be set only for IPv4 addresses");
-			return -1;
+			bb_error_msg_and_die("broadcast can be set only for IPv4 addresses");
 		}
 		brd = peer;
 		if (brd.bitlen <= 30) {
@@ -786,17 +784,18 @@ static int ipaddr_modify(int cmd, int argc, char **argv)
 
 	ll_init_map(&rth);
 
-	if ((req.ifa.ifa_index = ll_name_to_index(d)) == 0) {
-		bb_error_msg("cannot find device \"%s\"", d);
-		return -1;
+	req.ifa.ifa_index = ll_name_to_index(d);
+	if (req.ifa.ifa_index == 0) {
+		bb_error_msg_and_die("cannot find device \"%s\"", d);
 	}
 
 	if (rtnl_talk(&rth, &req.n, 0, 0, NULL, NULL, NULL) < 0)
-		exit(2);
+		return 2;
 
-	exit(0);
+	return 0;
 }
 
+/* Return value becomes exitcode. It's okay to not return at all */
 int do_ipaddr(int argc, char **argv)
 {
 	static const char *const commands[] = {
diff --git a/networking/libiproute/iplink.c b/networking/libiproute/iplink.c
index cb6ee96..0943726 100644
--- a/networking/libiproute/iplink.c
+++ b/networking/libiproute/iplink.c
@@ -22,63 +22,54 @@
 #include "utils.h"
 #include "ip_common.h"
 
-/* take from linux/sockios.h */
+/* taken from linux/sockios.h */
 #define SIOCSIFNAME	0x8923		/* set interface name */
 
-static int on_off(const char *msg)
+static void on_off(const char *msg) ATTRIBUTE_NORETURN;
+static void on_off(const char *msg)
 {
-	bb_error_msg("error: argument of \"%s\" must be \"on\" or \"off\"", msg);
-	return -1;
+	bb_error_msg_and_die("error: argument of \"%s\" must be \"on\" or \"off\"", msg);
 }
 
+/* Exits on error */
 static int get_ctl_fd(void)
 {
-	int s_errno;
 	int fd;
 
 	fd = socket(PF_INET, SOCK_DGRAM, 0);
 	if (fd >= 0)
 		return fd;
-	s_errno = errno;
 	fd = socket(PF_PACKET, SOCK_DGRAM, 0);
 	if (fd >= 0)
 		return fd;
 	fd = socket(PF_INET6, SOCK_DGRAM, 0);
 	if (fd >= 0)
 		return fd;
-	errno = s_errno;
-	bb_perror_msg("cannot create control socket");
-	return -1;
+	bb_perror_msg_and_die("cannot create control socket");
 }
 
-static int do_chflags(char *dev, uint32_t flags, uint32_t mask)
+/* Exits on error */
+static void do_chflags(char *dev, uint32_t flags, uint32_t mask)
 {
 	struct ifreq ifr;
 	int fd;
-	int err;
 
 	strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
 	fd = get_ctl_fd();
-	if (fd < 0)
-		return -1;
-	err = ioctl(fd, SIOCGIFFLAGS, &ifr);
-	if (err) {
-		bb_perror_msg("SIOCGIFFLAGS");
-		close(fd);
-		return -1;
+	if (ioctl(fd, SIOCGIFFLAGS, &ifr)) {
+		bb_perror_msg_and_die("SIOCGIFFLAGS");
 	}
-	if ((ifr.ifr_flags^flags)&mask) {
+	if ((ifr.ifr_flags ^ flags) & mask) {
 		ifr.ifr_flags &= ~mask;
-		ifr.ifr_flags |= mask&flags;
-		err = ioctl(fd, SIOCSIFFLAGS, &ifr);
-		if (err)
-			bb_perror_msg("SIOCSIFFLAGS");
+		ifr.ifr_flags |= mask & flags;
+		if (ioctl(fd, SIOCSIFFLAGS, &ifr))
+			bb_perror_msg_and_die("SIOCSIFFLAGS");
 	}
 	close(fd);
-	return err;
 }
 
-static int do_changename(char *dev, char *newdev)
+/* Exits on error */
+static void do_changename(char *dev, char *newdev)
 {
 	struct ifreq ifr;
 	int fd;
@@ -87,62 +78,46 @@ static int do_changename(char *dev, char *newdev)
 	strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
 	strncpy(ifr.ifr_newname, newdev, sizeof(ifr.ifr_newname));
 	fd = get_ctl_fd();
-	if (fd < 0)
-		return -1;
 	err = ioctl(fd, SIOCSIFNAME, &ifr);
 	if (err) {
-		bb_perror_msg("SIOCSIFNAME");
-		close(fd);
-		return -1;
+		bb_perror_msg_and_die("SIOCSIFNAME");
 	}
 	close(fd);
-	return err;
 }
 
-static int set_qlen(char *dev, int qlen)
+/* Exits on error */
+static void set_qlen(char *dev, int qlen)
 {
 	struct ifreq ifr;
 	int s;
 
 	s = get_ctl_fd();
-	if (s < 0)
-		return -1;
-
 	memset(&ifr, 0, sizeof(ifr));
 	strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
 	ifr.ifr_qlen = qlen;
 	if (ioctl(s, SIOCSIFTXQLEN, &ifr) < 0) {
-		bb_perror_msg("SIOCSIFXQLEN");
-		close(s);
-		return -1;
+		bb_perror_msg_and_die("SIOCSIFXQLEN");
 	}
 	close(s);
-
-	return 0;
 }
 
-static int set_mtu(char *dev, int mtu)
+/* Exits on error */
+static void set_mtu(char *dev, int mtu)
 {
 	struct ifreq ifr;
 	int s;
 
 	s = get_ctl_fd();
-	if (s < 0)
-		return -1;
-
 	memset(&ifr, 0, sizeof(ifr));
 	strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
 	ifr.ifr_mtu = mtu;
 	if (ioctl(s, SIOCSIFMTU, &ifr) < 0) {
-		bb_perror_msg("SIOCSIFMTU");
-		close(s);
-		return -1;
+		bb_perror_msg_and_die("SIOCSIFMTU");
 	}
 	close(s);
-
-	return 0;
 }
 
+/* Exits on error */
 static int get_address(char *dev, int *htype)
 {
 	struct ifreq ifr;
@@ -152,16 +127,13 @@ static int get_address(char *dev, int *htype)
 
 	s = socket(PF_PACKET, SOCK_DGRAM, 0);
 	if (s < 0) {
-		bb_perror_msg("socket(PF_PACKET)");
-		return -1;
+		bb_perror_msg_and_die("socket(PF_PACKET)");
 	}
 
 	memset(&ifr, 0, sizeof(ifr));
 	strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
 	if (ioctl(s, SIOCGIFINDEX, &ifr) < 0) {
-		bb_perror_msg("SIOCGIFINDEX");
-		close(s);
-		return -1;
+		bb_perror_msg_and_die("SIOCGIFINDEX");
 	}
 
 	memset(&me, 0, sizeof(me));
@@ -169,23 +141,20 @@ static int get_address(char *dev, int *htype)
 	me.sll_ifindex = ifr.ifr_ifindex;
 	me.sll_protocol = htons(ETH_P_LOOP);
 	if (bind(s, (struct sockaddr*)&me, sizeof(me)) == -1) {
-		bb_perror_msg("bind");
-		close(s);
-		return -1;
+		bb_perror_msg_and_die("bind");
 	}
 
 	alen = sizeof(me);
 	if (getsockname(s, (struct sockaddr*)&me, &alen) == -1) {
-		bb_perror_msg("getsockname");
-		close(s);
-		return -1;
+		bb_perror_msg_and_die("getsockname");
 	}
 	close(s);
 	*htype = me.sll_hatype;
 	return me.sll_halen;
 }
 
-static int parse_address(char *dev, int hatype, int halen, char *lla, struct ifreq *ifr)
+/* Exits on error */
+static void parse_address(char *dev, int hatype, int halen, char *lla, struct ifreq *ifr)
 {
 	int alen;
 
@@ -194,31 +163,26 @@ static int parse_address(char *dev, int hatype, int halen, char *lla, struct ifr
 	ifr->ifr_hwaddr.sa_family = hatype;
 	alen = ll_addr_a2n((unsigned char *)(ifr->ifr_hwaddr.sa_data), 14, lla);
 	if (alen < 0)
-		return -1;
+		exit(1);
 	if (alen != halen) {
-		bb_error_msg("wrong address (%s) length: expected %d bytes", lla, halen);
-		return -1;
+		bb_error_msg_and_die("wrong address (%s) length: expected %d bytes", lla, halen);
 	}
-	return 0;
 }
 
-static int set_address(struct ifreq *ifr, int brd)
+/* Exits on error */
+static void set_address(struct ifreq *ifr, int brd)
 {
 	int s;
 
 	s = get_ctl_fd();
-	if (s < 0)
-		return -1;
-	if (ioctl(s, brd?SIOCSIFHWBROADCAST:SIOCSIFHWADDR, ifr) < 0) {
-		bb_perror_msg(brd ? "SIOCSIFHWBROADCAST" : "SIOCSIFHWADDR");
-		close(s);
-		return -1;
+	if (ioctl(s, brd ? SIOCSIFHWBROADCAST  :SIOCSIFHWADDR, ifr) < 0) {
+		bb_perror_msg_and_die(brd ? "SIOCSIFHWBROADCAST" : "SIOCSIFHWADDR");
 	}
 	close(s);
-	return 0;
 }
 
 
+/* Return value becomes exitcode. It's okay to not return at all */
 static int do_set(int argc, char **argv)
 {
 	char *dev = NULL;
@@ -256,7 +220,7 @@ static int do_set(int argc, char **argv)
 			} else if (strcmp(*argv, "off") == 0) {
 				flags &= ~IFF_MULTICAST;
 			} else
-				return on_off("multicast");
+				on_off("multicast");
 		} else if (strcmp(*argv, "arp") == 0) {
 			NEXT_ARG();
 			mask |= IFF_NOARP;
@@ -265,7 +229,7 @@ static int do_set(int argc, char **argv)
 			} else if (strcmp(*argv, "off") == 0) {
 				flags |= IFF_NOARP;
 			} else
-				return on_off("noarp");
+				on_off("noarp");
 		} else if (strcmp(*argv, "addr") == 0) {
 			NEXT_ARG();
 			newaddr = *argv;
@@ -277,53 +241,44 @@ static int do_set(int argc, char **argv)
 				duparg2("dev", *argv);
 			dev = *argv;
 		}
-		argc--; argv++;
+		argc--;
+		argv++;
 	}
 
 	if (!dev) {
-		bb_error_msg(bb_msg_requires_arg, "\"dev\"");
-		exit(-1);
+		bb_error_msg_and_die(bb_msg_requires_arg, "\"dev\"");
 	}
 
 	if (newaddr || newbrd) {
 		halen = get_address(dev, &htype);
-		if (halen < 0)
-			return -1;
 		if (newaddr) {
-			if (parse_address(dev, htype, halen, newaddr, &ifr0) < 0)
-				return -1;
+			parse_address(dev, htype, halen, newaddr, &ifr0);
 		}
 		if (newbrd) {
-			if (parse_address(dev, htype, halen, newbrd, &ifr1) < 0)
-				return -1;
+			parse_address(dev, htype, halen, newbrd, &ifr1);
 		}
 	}
 
 	if (newname && strcmp(dev, newname)) {
-		if (do_changename(dev, newname) < 0)
-			return -1;
+		do_changename(dev, newname);
 		dev = newname;
 	}
 	if (qlen != -1) {
-		if (set_qlen(dev, qlen) < 0)
-			return -1;
+		set_qlen(dev, qlen);
 	}
 	if (mtu != -1) {
-		if (set_mtu(dev, mtu) < 0)
-			return -1;
+		set_mtu(dev, mtu);
 	}
 	if (newaddr || newbrd) {
 		if (newbrd) {
-			if (set_address(&ifr1, 1) < 0)
-				return -1;
+			set_address(&ifr1, 1);
 		}
 		if (newaddr) {
-			if (set_address(&ifr0, 0) < 0)
-				return -1;
+			set_address(&ifr0, 0);
 		}
 	}
 	if (mask)
-		return do_chflags(dev, flags, mask);
+		do_chflags(dev, flags, mask);
 	return 0;
 }
 
@@ -333,18 +288,19 @@ static int ipaddr_list_link(int argc, char **argv)
 	return ipaddr_list_or_flush(argc, argv, 0);
 }
 
+/* Return value becomes exitcode. It's okay to not return at all */
 int do_iplink(int argc, char **argv)
 {
-	if (argc > 0) {
-		if (matches(*argv, "set") == 0)
-			return do_set(argc-1, argv+1);
-		if (matches(*argv, "show") == 0 ||
-		    matches(*argv, "lst") == 0 ||
-		    matches(*argv, "list") == 0)
-			return ipaddr_list_link(argc-1, argv+1);
-	} else
+	if (argc <= 0)
 		return ipaddr_list_link(0, NULL);
 
-	bb_error_msg("command \"%s\" is unknown", *argv);
-	exit(-1);
+	if (matches(*argv, "set") == 0)
+		return do_set(argc-1, argv+1);
+
+	if (matches(*argv, "show") == 0 ||
+	    matches(*argv, "lst") == 0 ||
+	    matches(*argv, "list") == 0)
+		return ipaddr_list_link(argc-1, argv+1);
+
+	bb_error_msg_and_die("command \"%s\" is unknown", *argv);
 }
diff --git a/networking/libiproute/iproute.c b/networking/libiproute/iproute.c
index 27d37ac..bb0bfae 100644
--- a/networking/libiproute/iproute.c
+++ b/networking/libiproute/iproute.c
@@ -24,8 +24,7 @@
 #endif
 
 
-static struct
-{
+typedef struct filter_t {
 	int tb;
 	int flushed;
 	char *flushb;
@@ -45,12 +44,14 @@ static struct
 	inet_prefix mdst;
 	inet_prefix rsrc;
 	inet_prefix msrc;
-} filter;
+} filter_t;
+
+#define filter (*(filter_t*)&bb_common_bufsiz1)
 
 static int flush_update(void)
 {
 	if (rtnl_send(filter.rth, filter.flushb, filter.flushp) < 0) {
-		perror("Failed to send flush request\n");
+		bb_perror_msg("failed to send flush request");
 		return -1;
 	}
 	filter.flushp = 0;
@@ -273,7 +274,7 @@ static int print_route(struct sockaddr_nl *who ATTRIBUTE_UNUSED,
 		}
 		if ((r->rtm_flags & RTM_F_CLONED) || (ci && ci->rta_expires)) {
 			if (r->rtm_flags & RTM_F_CLONED) {
-				fprintf(fp, "%s    cache ", _SL_);
+				fprintf(fp, "%c    cache ", _SL_);
 			}
 			if (ci->rta_expires) {
 				fprintf(fp, " expires %dsec", ci->rta_expires / get_hz());
@@ -289,11 +290,12 @@ static int print_route(struct sockaddr_nl *who ATTRIBUTE_UNUSED,
 	if (tb[RTA_IIF] && filter.iifmask != -1) {
 		fprintf(fp, " iif %s", ll_index_to_name(*(int*)RTA_DATA(tb[RTA_IIF])));
 	}
-	fprintf(fp, "\n");
+	fputc('\n', fp);
 	fflush(fp);
 	return 0;
 }
 
+/* Return value becomes exitcode. It's okay to not return at all */
 static int iproute_modify(int cmd, unsigned flags, int argc, char **argv)
 {
 	struct rtnl_handle rth;
@@ -302,10 +304,10 @@ static int iproute_modify(int cmd, unsigned flags, int argc, char **argv)
 		struct rtmsg		r;
 		char			buf[1024];
 	} req;
-	char  mxbuf[256];
+	char mxbuf[256];
 	struct rtattr * mxrta = (void*)mxbuf;
 	unsigned mxlock = 0;
-	char  *d = NULL;
+	char *d = NULL;
 	int gw_ok = 0;
 	int dst_ok = 0;
 	int proto_ok = 0;
@@ -384,8 +386,9 @@ static int iproute_modify(int cmd, unsigned flags, int argc, char **argv)
 			if (strcmp(*argv, "to") == 0) {
 				NEXT_ARG();
 			}
-			if ((**argv < '0' || **argv > '9') &&
-			    rtnl_rtntype_a2n(&type, *argv) == 0) {
+			if ((**argv < '0' || **argv > '9')
+			 && rtnl_rtntype_a2n(&type, *argv) == 0
+			) {
 				NEXT_ARG();
 				req.r.rtm_type = type;
 				type_ok = 1;
@@ -408,7 +411,7 @@ static int iproute_modify(int cmd, unsigned flags, int argc, char **argv)
 	}
 
 	if (rtnl_open(&rth, 0) < 0) {
-		exit(1);
+		return 1;
 	}
 
 	if (d)  {
@@ -419,8 +422,7 @@ static int iproute_modify(int cmd, unsigned flags, int argc, char **argv)
 		if (d) {
 			idx = ll_name_to_index(d);
 			if (idx == 0) {
-				bb_error_msg("cannot find device \"%s\"", d);
-				return -1;
+				bb_error_msg_and_die("cannot find device \"%s\"", d);
 			}
 			addattr32(&req.n, sizeof(req), RTA_OIF, idx);
 		}
@@ -438,7 +440,7 @@ static int iproute_modify(int cmd, unsigned flags, int argc, char **argv)
 	}
 
 	if (rtnl_talk(&rth, &req.n, 0, 0, NULL, NULL, NULL) < 0) {
-		exit(2);
+		return 2;
 	}
 
 	return 0;
@@ -467,21 +469,21 @@ static int rtnl_rtcache_request(struct rtnl_handle *rth, int family)
 	return sendto(rth->fd, (void*)&req, sizeof(req), 0, (struct sockaddr*)&nladdr, sizeof(nladdr));
 }
 
-static int iproute_flush_cache(void)
+static void iproute_flush_cache(void)
 {
 	static const char fn[] = "/proc/sys/net/ipv4/route/flush";
 	int flush_fd = open(fn, O_WRONLY);
+
 	if (flush_fd < 0) {
 		bb_perror_msg("cannot open '%s'", fn);
-		return -1;
+		return;
 	}
 
 	if (write(flush_fd, "-1", 2) < 2) {
 		bb_perror_msg("cannot flush routing cache");
-		return -1;
+		return;
 	}
 	close(flush_fd);
-	return 0;
 }
 
 static void iproute_reset_filter(void)
@@ -491,6 +493,7 @@ static void iproute_reset_filter(void)
 	filter.msrc.bitlen = -1;
 }
 
+/* Return value becomes exitcode. It's okay to not return at all */
 static int iproute_list_or_flush(int argc, char **argv, int flush)
 {
 	int do_ipv6 = preferred_family;
@@ -501,10 +504,8 @@ static int iproute_list_or_flush(int argc, char **argv, int flush)
 	iproute_reset_filter();
 	filter.tb = RT_TABLE_MAIN;
 
-	if (flush && argc <= 0) {
-		bb_error_msg(bb_msg_requires_arg, "\"ip route flush\"");
-		return -1;
-	}
+	if (flush && argc <= 0)
+		bb_error_msg_and_die(bb_msg_requires_arg, "\"ip route flush\"");
 
 	while (argc > 0) {
 		if (matches(*argv, "protocol") == 0) {
@@ -572,7 +573,8 @@ static int iproute_list_or_flush(int argc, char **argv, int flush)
 				filter.rdst = filter.mdst;
 			}
 		}
-		argc--; argv++;
+		argc--;
+		argv++;
 	}
 
 	if (do_ipv6 == AF_UNSPEC && filter.tb) {
@@ -580,7 +582,7 @@ static int iproute_list_or_flush(int argc, char **argv, int flush)
 	}
 
 	if (rtnl_open(&rth, 0) < 0) {
-		exit(1);
+		return 1;
 	}
 
 	ll_init_map(&rth);
@@ -589,15 +591,16 @@ static int iproute_list_or_flush(int argc, char **argv, int flush)
 		int idx;
 
 		if (id) {
-			if ((idx = ll_name_to_index(id)) == 0) {
-				bb_error_msg("cannot find device \"%s\"", id);
-				return -1;
+			idx = ll_name_to_index(id);
+			if (idx == 0) {
+				bb_error_msg_and_die("cannot find device \"%s\"", id);
 			}
 			filter.iif = idx;
 			filter.iifmask = -1;
 		}
 		if (od) {
-			if ((idx = ll_name_to_index(od)) == 0) {
+			idx = ll_name_to_index(od);
+			if (idx == 0) {
 				bb_error_msg("cannot find device \"%s\"", od);
 			}
 			filter.oif = idx;
@@ -622,20 +625,17 @@ static int iproute_list_or_flush(int argc, char **argv, int flush)
 
 		for (;;) {
 			if (rtnl_wilddump_request(&rth, do_ipv6, RTM_GETROUTE) < 0) {
-				perror("Cannot send dump request");
-				return -1;
+				bb_perror_msg_and_die("cannot send dump request");
 			}
 			filter.flushed = 0;
 			if (rtnl_dump_filter(&rth, print_route, stdout, NULL, NULL) < 0) {
-				bb_error_msg("flush terminated");
-				return -1;
+				bb_error_msg_and_die("flush terminated");
 			}
 			if (filter.flushed == 0) {
-				fflush(stdout);
 				return 0;
 			}
-			if (flush_update() < 0)
-				exit(1);
+			if (flush_update())
+				return 1;
 		}
 	}
 
@@ -653,10 +653,11 @@ static int iproute_list_or_flush(int argc, char **argv, int flush)
 		bb_error_msg_and_die("dump terminated");
 	}
 
-	exit(0);
+	return 0;
 }
 
 
+/* Return value becomes exitcode. It's okay to not return at all */
 static int iproute_get(int argc, char **argv)
 {
 	struct rtnl_handle rth;
@@ -734,7 +735,8 @@ static int iproute_get(int argc, char **argv)
 				}
 				req.r.rtm_dst_len = addr.bitlen;
 			}
-			argc--; argv++;
+			argc--;
+			argv++;
 		}
 	}
 
@@ -743,7 +745,7 @@ static int iproute_get(int argc, char **argv)
 	}
 
 	if (rtnl_open(&rth, 0) < 0)
-		exit(1);
+		return 1;
 
 	ll_init_map(&rth);
 
@@ -751,16 +753,16 @@ static int iproute_get(int argc, char **argv)
 		int idx;
 
 		if (idev) {
-			if ((idx = ll_name_to_index(idev)) == 0) {
-				bb_error_msg("cannot find device \"%s\"", idev);
-				return -1;
+			idx = ll_name_to_index(idev);
+			if (idx == 0) {
+				bb_error_msg_and_die("cannot find device \"%s\"", idev);
 			}
 			addattr32(&req.n, sizeof(req), RTA_IIF, idx);
 		}
 		if (odev) {
-			if ((idx = ll_name_to_index(odev)) == 0) {
-				bb_error_msg("cannot find device \"%s\"", odev);
-				return -1;
+			idx = ll_name_to_index(odev);
+			if (idx == 0) {
+				bb_error_msg_and_die("cannot find device \"%s\"", odev);
 			}
 			addattr32(&req.n, sizeof(req), RTA_OIF, idx);
 		}
@@ -771,7 +773,7 @@ static int iproute_get(int argc, char **argv)
 	}
 
 	if (rtnl_talk(&rth, &req.n, 0, 0, &req.n, NULL, NULL) < 0) {
-		exit(2);
+		return 2;
 	}
 
 	if (connected && !from_ok) {
@@ -784,13 +786,11 @@ static int iproute_get(int argc, char **argv)
 		}
 
 		if (req.n.nlmsg_type != RTM_NEWROUTE) {
-			bb_error_msg("not a route?");
-			return -1;
+			bb_error_msg_and_die("not a route?");
 		}
 		len -= NLMSG_LENGTH(sizeof(*r));
 		if (len < 0) {
-			bb_error_msg("wrong len %d", len);
-			return -1;
+			bb_error_msg_and_die("wrong len %d", len);
 		}
 
 		memset(tb, 0, sizeof(tb));
@@ -800,8 +800,7 @@ static int iproute_get(int argc, char **argv)
 			tb[RTA_PREFSRC]->rta_type = RTA_SRC;
 			r->rtm_src_len = 8*RTA_PAYLOAD(tb[RTA_PREFSRC]);
 		} else if (!tb[RTA_SRC]) {
-			bb_error_msg("failed to connect the route");
-			return -1;
+			bb_error_msg_and_die("failed to connect the route");
 		}
 		if (!odev && tb[RTA_OIF]) {
 			tb[RTA_OIF]->rta_type = 0;
@@ -816,17 +815,19 @@ static int iproute_get(int argc, char **argv)
 		req.n.nlmsg_type = RTM_GETROUTE;
 
 		if (rtnl_talk(&rth, &req.n, 0, 0, &req.n, NULL, NULL) < 0) {
-			exit(2);
+			return 2;
 		}
 	}
 
 	if (print_route(NULL, &req.n, (void*)stdout) < 0) {
+// how is this useful?
 		bb_error_msg_and_die("an error :-)");
 	}
 
-	exit(0);
+	return 0;
 }
 
+/* Return value becomes exitcode. It's okay to not return at all */
 int do_iproute(int argc, char **argv)
 {
 	static const char * const ip_route_commands[] = {
diff --git a/networking/libiproute/iprule.c b/networking/libiproute/iprule.c
index 4b31303..d4cf282 100644
--- a/networking/libiproute/iprule.c
+++ b/networking/libiproute/iprule.c
@@ -155,11 +155,12 @@ static int print_rule(struct sockaddr_nl *who ATTRIBUTE_UNUSED,
 	} else if (r->rtm_type != RTN_UNICAST)
 		fprintf(fp, "%s", rtnl_rtntype_n2a(r->rtm_type, b1, sizeof(b1)));
 
-	fprintf(fp, "\n");
+	fputc('\n', fp);
 	fflush(fp);
 	return 0;
 }
 
+/* Return value becomes exitcode. It's okay to not return at all */
 static int iprule_list(int argc, char **argv)
 {
 	struct rtnl_handle rth;
@@ -178,19 +179,18 @@ static int iprule_list(int argc, char **argv)
 		return 1;
 
 	if (rtnl_wilddump_request(&rth, af, RTM_GETRULE) < 0) {
-		bb_perror_msg("Cannot send dump request");
-		return 1;
+		bb_perror_msg_and_die("cannot send dump request");
 	}
 
 	if (rtnl_dump_filter(&rth, print_rule, stdout, NULL, NULL) < 0) {
-		bb_error_msg("Dump terminated");
-		return 1;
+		bb_error_msg_and_die("dump terminated");
 	}
 
 	return 0;
 }
 
 
+/* Return value becomes exitcode. It's okay to not return at all */
 static int iprule_modify(int cmd, int argc, char **argv)
 {
 	int table_ok = 0;
@@ -282,7 +282,8 @@ static int iprule_modify(int cmd, int argc, char **argv)
 			if (matches(*argv, "help") == 0)
 				bb_show_usage();
 			if (rtnl_rtntype_a2n(&type, *argv))
-				invarg("Failed to parse rule type", *argv);
+// bogus-looking error message "invalid argument 'cannot parse rule type' to '<*argv>'"
+				invarg("cannot parse rule type", *argv);
 			req.r.rtm_type = type;
 		}
 		argc--;
@@ -304,6 +305,7 @@ static int iprule_modify(int cmd, int argc, char **argv)
 	return 0;
 }
 
+/* Return value becomes exitcode. It's okay to not return at all */
 int do_iprule(int argc, char **argv)
 {
 	static const char * const ip_rule_commands[] =
@@ -331,4 +333,3 @@ int do_iprule(int argc, char **argv)
 	}
 	return iprule_modify(cmd, argc-1, argv+1);
 }
-
diff --git a/networking/libiproute/iptunnel.c b/networking/libiproute/iptunnel.c
index e2e75fc..52a5099 100644
--- a/networking/libiproute/iptunnel.c
+++ b/networking/libiproute/iptunnel.c
@@ -18,9 +18,6 @@
 #include <sys/socket.h>
 #include <sys/ioctl.h>
 
-#include <string.h>
-#include <unistd.h>
-
 #include <netinet/ip.h>
 
 #include <net/if.h>
@@ -37,6 +34,7 @@
 #include "ip_common.h"
 
 
+/* Dies on error */
 static int do_ioctl_get_ifindex(char *dev)
 {
 	struct ifreq ifr;
@@ -45,8 +43,7 @@ static int do_ioctl_get_ifindex(char *dev)
 	strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
 	fd = xsocket(AF_INET, SOCK_DGRAM, 0);
 	if (ioctl(fd, SIOCGIFINDEX, &ifr)) {
-		bb_perror_msg("ioctl");
-		return 0;
+		bb_perror_msg_and_die("SIOCGIFINDEX");
 	}
 	close(fd);
 	return ifr.ifr_ifindex;
@@ -60,31 +57,28 @@ static int do_ioctl_get_iftype(char *dev)
 	strncpy(ifr.ifr_name, dev, sizeof(ifr.ifr_name));
 	fd = xsocket(AF_INET, SOCK_DGRAM, 0);
 	if (ioctl(fd, SIOCGIFHWADDR, &ifr)) {
-		bb_perror_msg("ioctl");
+		bb_perror_msg("SIOCGIFHWADDR");
 		return -1;
 	}
 	close(fd);
 	return ifr.ifr_addr.sa_family;
 }
 
-
 static char *do_ioctl_get_ifname(int idx)
 {
-	static struct ifreq ifr;
+	struct ifreq ifr;
 	int fd;
 
 	ifr.ifr_ifindex = idx;
 	fd = xsocket(AF_INET, SOCK_DGRAM, 0);
 	if (ioctl(fd, SIOCGIFNAME, &ifr)) {
-		bb_perror_msg("ioctl");
+		bb_perror_msg("SIOCGIFNAME");
 		return NULL;
 	}
 	close(fd);
-	return ifr.ifr_name;
+	return xstrndup(ifr.ifr_name, sizeof(ifr.ifr_name));
 }
 
-
-
 static int do_get_ioctl(const char *basedev, struct ip_tunnel_parm *p)
 {
 	struct ifreq ifr;
@@ -96,17 +90,17 @@ static int do_get_ioctl(const char *basedev, struct ip_tunnel_parm *p)
 	fd = xsocket(AF_INET, SOCK_DGRAM, 0);
 	err = ioctl(fd, SIOCGETTUNNEL, &ifr);
 	if (err) {
-		bb_perror_msg("ioctl");
+		bb_perror_msg("SIOCGETTUNNEL");
 	}
 	close(fd);
 	return err;
 }
 
+/* Dies on error, otherwise returns 0 */
 static int do_add_ioctl(int cmd, const char *basedev, struct ip_tunnel_parm *p)
 {
 	struct ifreq ifr;
 	int fd;
-	int err;
 
 	if (cmd == SIOCCHGTUNNEL && p->name[0]) {
 		strncpy(ifr.ifr_name, p->name, sizeof(ifr.ifr_name));
@@ -115,19 +109,18 @@ static int do_add_ioctl(int cmd, const char *basedev, struct ip_tunnel_parm *p)
 	}
 	ifr.ifr_ifru.ifru_data = (void*)p;
 	fd = xsocket(AF_INET, SOCK_DGRAM, 0);
-	err = ioctl(fd, cmd, &ifr);
-	if (err) {
-		bb_perror_msg("ioctl");
+	if (ioctl(fd, cmd, &ifr)) {
+		bb_perror_msg_and_die("ioctl");
 	}
 	close(fd);
-	return err;
+	return 0;
 }
 
+/* Dies on error, otherwise returns 0 */
 static int do_del_ioctl(const char *basedev, struct ip_tunnel_parm *p)
 {
 	struct ifreq ifr;
 	int fd;
-	int err;
 
 	if (p->name[0]) {
 		strncpy(ifr.ifr_name, p->name, sizeof(ifr.ifr_name));
@@ -136,15 +129,15 @@ static int do_del_ioctl(const char *basedev, struct ip_tunnel_parm *p)
 	}
 	ifr.ifr_ifru.ifru_data = (void*)p;
 	fd = xsocket(AF_INET, SOCK_DGRAM, 0);
-	err = ioctl(fd, SIOCDELTUNNEL, &ifr);
-	if (err) {
-		bb_perror_msg("ioctl");
+	if (ioctl(fd, SIOCDELTUNNEL, &ifr)) {
+		bb_perror_msg_and_die("SIOCDELTUNNEL");
 	}
 	close(fd);
-	return err;
+	return 0;
 }
 
-static int parse_args(int argc, char **argv, int cmd, struct ip_tunnel_parm *p)
+/* Dies on error */
+static void parse_args(int argc, char **argv, int cmd, struct ip_tunnel_parm *p)
 {
 	int count = 0;
 	char medium[IFNAMSIZ];
@@ -164,27 +157,23 @@ static int parse_args(int argc, char **argv, int cmd, struct ip_tunnel_parm *p)
 			if (strcmp(*argv, "ipip") == 0 ||
 			    strcmp(*argv, "ip/ip") == 0) {
 				if (p->iph.protocol && p->iph.protocol != IPPROTO_IPIP) {
-					bb_error_msg("you managed to ask for more than one tunnel mode");
-					exit(-1);
+					bb_error_msg_and_die("you managed to ask for more than one tunnel mode");
 				}
 				p->iph.protocol = IPPROTO_IPIP;
 			} else if (strcmp(*argv, "gre") == 0 ||
 				   strcmp(*argv, "gre/ip") == 0) {
 				if (p->iph.protocol && p->iph.protocol != IPPROTO_GRE) {
-					bb_error_msg("you managed to ask for more than one tunnel mode");
-					exit(-1);
+					bb_error_msg_and_die("you managed to ask for more than one tunnel mode");
 				}
 				p->iph.protocol = IPPROTO_GRE;
 			} else if (strcmp(*argv, "sit") == 0 ||
 				   strcmp(*argv, "ipv6/ip") == 0) {
 				if (p->iph.protocol && p->iph.protocol != IPPROTO_IPV6) {
-					bb_error_msg("you managed to ask for more than one tunnel mode");
-					exit(-1);
+					bb_error_msg_and_die("you managed to ask for more than one tunnel mode");
 				}
 				p->iph.protocol = IPPROTO_IPV6;
 			} else {
-				bb_error_msg("cannot guess tunnel mode");
-				exit(-1);
+				bb_error_msg_and_die("cannot guess tunnel mode");
 			}
 		} else if (strcmp(*argv, "key") == 0) {
 			unsigned uval;
@@ -195,8 +184,7 @@ static int parse_args(int argc, char **argv, int cmd, struct ip_tunnel_parm *p)
 				p->i_key = p->o_key = get_addr32(*argv);
 			else {
 				if (get_unsigned(&uval, *argv, 0)<0) {
-					bb_error_msg("invalid value of \"key\"");
-					exit(-1);
+					bb_error_msg_and_die("invalid value of \"key\"");
 				}
 				p->i_key = p->o_key = htonl(uval);
 			}
@@ -208,8 +196,7 @@ static int parse_args(int argc, char **argv, int cmd, struct ip_tunnel_parm *p)
 				p->o_key = get_addr32(*argv);
 			else {
 				if (get_unsigned(&uval, *argv, 0)<0) {
-					bb_error_msg("invalid value of \"ikey\"");
-					exit(-1);
+					bb_error_msg_and_die("invalid value of \"ikey\"");
 				}
 				p->i_key = htonl(uval);
 			}
@@ -221,8 +208,7 @@ static int parse_args(int argc, char **argv, int cmd, struct ip_tunnel_parm *p)
 				p->o_key = get_addr32(*argv);
 			else {
 				if (get_unsigned(&uval, *argv, 0)<0) {
-					bb_error_msg("invalid value of \"okey\"");
-					exit(-1);
+					bb_error_msg_and_die("invalid value of \"okey\"");
 				}
 				p->o_key = htonl(uval);
 			}
@@ -286,15 +272,15 @@ static int parse_args(int argc, char **argv, int cmd, struct ip_tunnel_parm *p)
 				struct ip_tunnel_parm old_p;
 				memset(&old_p, 0, sizeof(old_p));
 				if (do_get_ioctl(*argv, &old_p))
-					return -1;
+					exit(1);
 				*p = old_p;
 			}
 		}
 		count++;
-		argc--; argv++;
+		argc--;
+		argv++;
 	}
 
-
 	if (p->iph.protocol == 0) {
 		if (memcmp(p->name, "gre", 3) == 0)
 			p->iph.protocol = IPPROTO_GRE;
@@ -306,15 +292,12 @@ static int parse_args(int argc, char **argv, int cmd, struct ip_tunnel_parm *p)
 
 	if (p->iph.protocol == IPPROTO_IPIP || p->iph.protocol == IPPROTO_IPV6) {
 		if ((p->i_flags & GRE_KEY) || (p->o_flags & GRE_KEY)) {
-			bb_error_msg("keys are not allowed with ipip and sit");
-			return -1;
+			bb_error_msg_and_die("keys are not allowed with ipip and sit");
 		}
 	}
 
 	if (medium[0]) {
 		p->link = do_ioctl_get_ifindex(medium);
-		if (p->link == 0)
-			return -1;
 	}
 
 	if (p->i_key == 0 && IN_MULTICAST(ntohl(p->iph.daddr))) {
@@ -326,23 +309,20 @@ static int parse_args(int argc, char **argv, int cmd, struct ip_tunnel_parm *p)
 		p->o_flags |= GRE_KEY;
 	}
 	if (IN_MULTICAST(ntohl(p->iph.daddr)) && !p->iph.saddr) {
-		bb_error_msg("broadcast tunnel requires a source address");
-		return -1;
+		bb_error_msg_and_die("broadcast tunnel requires a source address");
 	}
-	return 0;
 }
 
 
+/* Return value becomes exitcode. It's okay to not return at all */
 static int do_add(int cmd, int argc, char **argv)
 {
 	struct ip_tunnel_parm p;
 
-	if (parse_args(argc, argv, cmd, &p) < 0)
-		return -1;
+	parse_args(argc, argv, cmd, &p);
 
 	if (p.iph.ttl && p.iph.frag_off == 0) {
-		bb_error_msg("ttl != 0 and noptmudisc are incompatible");
-		return -1;
+		bb_error_msg_and_die("ttl != 0 and noptmudisc are incompatible");
 	}
 
 	switch (p.iph.protocol) {
@@ -353,18 +333,16 @@ static int do_add(int cmd, int argc, char **argv)
 	case IPPROTO_IPV6:
 		return do_add_ioctl(cmd, "sit0", &p);
 	default:
-		bb_error_msg("cannot determine tunnel mode (ipip, gre or sit)");
-		return -1;
+		bb_error_msg_and_die("cannot determine tunnel mode (ipip, gre or sit)");
 	}
-	return -1;
 }
 
+/* Return value becomes exitcode. It's okay to not return at all */
 static int do_del(int argc, char **argv)
 {
 	struct ip_tunnel_parm p;
 
-	if (parse_args(argc, argv, SIOCDELTUNNEL, &p) < 0)
-		return -1;
+	parse_args(argc, argv, SIOCDELTUNNEL, &p);
 
 	switch (p.iph.protocol) {
 	case IPPROTO_IPIP:
@@ -376,7 +354,6 @@ static int do_del(int argc, char **argv)
 	default:
 		return do_del_ioctl(p.name, &p);
 	}
-	return -1;
 }
 
 static void print_tunnel(struct ip_tunnel_parm *p)
@@ -399,8 +376,10 @@ static void print_tunnel(struct ip_tunnel_parm *p)
 	       p->iph.daddr ? s1 : "any", p->iph.saddr ? s2 : "any");
 	if (p->link) {
 		char *n = do_ioctl_get_ifname(p->link);
-		if (n)
+		if (n) {
 			printf(" dev %s ", n);
+			free(n);
+		}
 	}
 	if (p->iph.ttl)
 		printf(" ttl %d ", p->iph.ttl);
@@ -428,16 +407,16 @@ static void print_tunnel(struct ip_tunnel_parm *p)
 	}
 
 	if (p->i_flags & GRE_SEQ)
-		printf("%s  Drop packets out of sequence.\n", _SL_);
+		printf("%c  Drop packets out of sequence.\n", _SL_);
 	if (p->i_flags & GRE_CSUM)
-		printf("%s  Checksum in received packet is required.", _SL_);
+		printf("%c  Checksum in received packet is required.", _SL_);
 	if (p->o_flags & GRE_SEQ)
-		printf("%s  Sequence packets on output.", _SL_);
+		printf("%c  Sequence packets on output.", _SL_);
 	if (p->o_flags & GRE_CSUM)
-		printf("%s  Checksum output packets.", _SL_);
+		printf("%c  Checksum output packets.", _SL_);
 }
 
-static int do_tunnels_list(struct ip_tunnel_parm *p)
+static void do_tunnels_list(struct ip_tunnel_parm *p)
 {
 	char name[IFNAMSIZ];
 	unsigned long rx_bytes, rx_packets, rx_errs, rx_drops,
@@ -450,8 +429,8 @@ static int do_tunnels_list(struct ip_tunnel_parm *p)
 	FILE *fp = fopen("/proc/net/dev", "r");
 
 	if (fp == NULL) {
-		perror("fopen");
-		return -1;
+		bb_perror_msg("fopen");
+		return;
 	}
 
 	fgets(buf, sizeof(buf), fp);
@@ -465,7 +444,7 @@ static int do_tunnels_list(struct ip_tunnel_parm *p)
 		if (ptr == NULL ||
 		    (*ptr++ = 0, sscanf(buf, "%s", name) != 1)) {
 			bb_error_msg("wrong format of /proc/net/dev. Sorry");
-			return -1;
+			return;
 		}
 		if (sscanf(ptr, "%lu%lu%lu%lu%lu%lu%lu%*d%lu%lu%lu%lu%lu%lu%lu",
 			   &rx_bytes, &rx_packets, &rx_errs, &rx_drops,
@@ -477,7 +456,7 @@ static int do_tunnels_list(struct ip_tunnel_parm *p)
 			continue;
 		type = do_ioctl_get_iftype(name);
 		if (type == -1) {
-			bb_error_msg("failed to get type of [%s]", name);
+			bb_error_msg("cannot get type of [%s]", name);
 			continue;
 		}
 		if (type != ARPHRD_TUNNEL && type != ARPHRD_IPGRE && type != ARPHRD_SIT)
@@ -494,16 +473,15 @@ static int do_tunnels_list(struct ip_tunnel_parm *p)
 		print_tunnel(&p1);
 		puts("");
 	}
-	return 0;
 }
 
+/* Return value becomes exitcode. It's okay to not return at all */
 static int do_show(int argc, char **argv)
 {
 	int err;
 	struct ip_tunnel_parm p;
 
-	if (parse_args(argc, argv, SIOCGETTUNNEL, &p) < 0)
-		return -1;
+	parse_args(argc, argv, SIOCGETTUNNEL, &p);
 
 	switch (p.iph.protocol) {
 	case IPPROTO_IPIP:
@@ -527,6 +505,7 @@ static int do_show(int argc, char **argv)
 	return 0;
 }
 
+/* Return value becomes exitcode. It's okay to not return at all */
 int do_iptunnel(int argc, char **argv)
 {
 	if (argc > 0) {
diff --git a/networking/libiproute/ll_map.c b/networking/libiproute/ll_map.c
index f429763..a8fcd7f 100644
--- a/networking/libiproute/ll_map.c
+++ b/networking/libiproute/ll_map.c
@@ -54,7 +54,7 @@ int ll_remember_index(struct sockaddr_nl *who, struct nlmsghdr *n, void *arg)
 
 	h = ifi->ifi_index&0xF;
 
-	for (imp=&idxmap[h]; (im=*imp)!=NULL; imp = &im->next)
+	for (imp = &idxmap[h]; (im = *imp) != NULL; imp = &im->next)
 		if (im->index == ifi->ifi_index)
 			break;
 
@@ -87,7 +87,7 @@ const char *ll_idx_n2a(int idx, char *buf)
 
 	if (idx == 0)
 		return "*";
-	for (im = idxmap[idx&0xF]; im; im = im->next)
+	for (im = idxmap[idx & 0xF]; im; im = im->next)
 		if (im->index == idx)
 			return im->name;
 	snprintf(buf, 16, "if%d", idx);
@@ -108,7 +108,7 @@ int ll_index_to_type(int idx)
 
 	if (idx == 0)
 		return -1;
-	for (im = idxmap[idx&0xF]; im; im = im->next)
+	for (im = idxmap[idx & 0xF]; im; im = im->next)
 		if (im->index == idx)
 			return im->type;
 	return -1;
@@ -121,16 +121,18 @@ unsigned ll_index_to_flags(int idx)
 	if (idx == 0)
 		return 0;
 
-	for (im = idxmap[idx&0xF]; im; im = im->next)
+	for (im = idxmap[idx & 0xF]; im; im = im->next)
 		if (im->index == idx)
 			return im->flags;
 	return 0;
 }
 
+// TODO: caching is not warranted - no users which repeatedly call it
 int ll_name_to_index(char *name)
 {
 	static char ncache[16];
 	static int icache;
+
 	struct idxmap *im;
 	int sock_fd;
 	int i;
@@ -139,7 +141,7 @@ int ll_name_to_index(char *name)
 		return 0;
 	if (icache && strcmp(name, ncache) == 0)
 		return icache;
-	for (i=0; i<16; i++) {
+	for (i = 0; i < 16; i++) {
 		for (im = idxmap[i]; im; im = im->next) {
 			if (strcmp(im->name, name) == 0) {
 				icache = im->index;
diff --git a/networking/libiproute/utils.c b/networking/libiproute/utils.c
index 591c893..601e45b 100644
--- a/networking/libiproute/utils.c
+++ b/networking/libiproute/utils.c
@@ -13,9 +13,6 @@
 
 #include "libbb.h"
 
-#include <string.h>
-#include <unistd.h>
-
 #include "utils.h"
 #include "inet_common.h"
 
@@ -197,7 +194,7 @@ int get_prefix_1(inet_prefix * dst, char *arg, int family)
 			dst->bitlen = plen;
 		}
 	}
-  done:
+ done:
 	if (slash)
 		*slash = '/';
 	return err;
diff --git a/networking/libiproute/utils.h b/networking/libiproute/utils.h
index 556541f..27afb32 100644
--- a/networking/libiproute/utils.h
+++ b/networking/libiproute/utils.h
@@ -9,13 +9,12 @@
 #include "rtm_map.h"
 
 extern int preferred_family;
-extern int show_stats;
-extern int show_details;
-extern int show_raw;
-extern int resolve_hosts;
-extern int oneline;
-//FIXME! Appears in two .h files!
-extern const char * _SL_;
+extern smallint show_stats;    /* UNUSED */
+extern smallint show_details;  /* UNUSED */
+extern smallint show_raw;      /* UNUSED */
+extern smallint resolve_hosts; /* UNUSED */
+extern smallint oneline;
+extern char _SL_;
 
 #ifndef IPPROTO_ESP
 #define IPPROTO_ESP	50
@@ -80,7 +79,7 @@ void invarg(const char *, const char *) ATTRIBUTE_NORETURN;
 void duparg(const char *, const char *) ATTRIBUTE_NORETURN;
 void duparg2(const char *, const char *) ATTRIBUTE_NORETURN;
 int matches(const char *arg, const char *pattern);
-extern int inet_addr_match(inet_prefix *a, inet_prefix *b, int bits);
+int inet_addr_match(inet_prefix *a, inet_prefix *b, int bits);
 
 const char *dnet_ntop(int af, const void *addr, char *str, size_t len);
 int dnet_pton(int af, const char *src, void *addr);