introduce and use xdup2(int, int)

stop checking whether setsockopt_reuseaddr(int fd) was successful (it always is)
remove second parameter (sockllen) from xmalloc_sockaddr2xxxxx functions

sockaddr2str                                         142     156     +14
collect_blk                                          467     474      +7
xdup2                                                 28      33      +5
singlemount                                         4456    4454      -2
print_host                                           214     212      -2
nslookup_main                                        139     137      -2
ftpgetput_main                                       414     412      -2
udhcpd_main                                         1258    1255      -3
udhcpc_main                                         2405    2402      -3
traceroute_main                                     4125    4122      -3
nc_main                                             1072    1069      -3
buffer_fill_and_print                                 76      73      -3
xmalloc_sockaddr2hostonly_noport                      18      14      -4
xmalloc_sockaddr2host_noport                          18      14      -4
xmalloc_sockaddr2host                                 15      11      -4
xmalloc_sockaddr2dotted_noport                        18      14      -4
xmalloc_sockaddr2dotted                               18      14      -4
wget_main                                           2618    2614      -4
ping_main                                            393     389      -4
ip_port_str                                          120     115      -5
dhcprelay_main                                      1146    1141      -5
dnsd_main                                           1531    1525      -6
passwd_main                                         1110    1102      -8
udhcp_kernel_packet                                  206     197      -9
udhcp_listen_socket                                  154     144     -10
getty_main                                          2576    2566     -10
setup                                                655     640     -15
xmove_fd                                              51      34     -17
dolisten                                             759     742     -17
tcpudpsvd_main                                      1866    1836     -30
startservice                                         339     299     -40

23 files changed, 95 insertions, 107 deletions

diff --git a/include/libbb.h b/include/libbb.h
index 52bc339..651c48b 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -241,6 +241,7 @@ extern char *bb_get_last_path_component(char *path);
 
 int ndelay_on(int fd);
 int ndelay_off(int fd);
+void xdup2(int, int);
 void xmove_fd(int, int);
 
 
@@ -288,8 +289,7 @@ ssize_t xsendto(int s, const void *buf, size_t len, const struct sockaddr *to,
  * time out. Linux does not allow multiple live binds on same ip:port
  * regardless of SO_REUSEADDR (unlike some other flavors of Unix).
  * Turn it on before you call bind(). */
-//TODO: it seems like in Linux this never fails. Change to void, eliminate error checks
-int setsockopt_reuseaddr(int fd);
+void setsockopt_reuseaddr(int fd); /* On Linux this never fails. */
 int setsockopt_broadcast(int fd);
 /* NB: returns port in host byte order */
 unsigned bb_lookup_port(const char *port, const char *protocol, unsigned default_port);
@@ -360,14 +360,14 @@ void set_nport(len_and_sockaddr *lsa, unsigned port);
 /* Retrieve sin[6]_port or return -1 for non-INET[6] lsa's */
 int get_nport(const struct sockaddr *sa);
 /* Reverse DNS. Returns NULL on failure. */
-char* xmalloc_sockaddr2host(const struct sockaddr *sa, socklen_t salen);
+char* xmalloc_sockaddr2host(const struct sockaddr *sa);
 /* This one doesn't append :PORTNUM */
-char* xmalloc_sockaddr2host_noport(const struct sockaddr *sa, socklen_t salen);
+char* xmalloc_sockaddr2host_noport(const struct sockaddr *sa);
 /* This one also doesn't fall back to dotted IP (returns NULL) */
-char* xmalloc_sockaddr2hostonly_noport(const struct sockaddr *sa, socklen_t salen);
+char* xmalloc_sockaddr2hostonly_noport(const struct sockaddr *sa);
 /* inet_[ap]ton on steroids */
-char* xmalloc_sockaddr2dotted(const struct sockaddr *sa, socklen_t salen);
-char* xmalloc_sockaddr2dotted_noport(const struct sockaddr *sa, socklen_t salen);
+char* xmalloc_sockaddr2dotted(const struct sockaddr *sa);
+char* xmalloc_sockaddr2dotted_noport(const struct sockaddr *sa);
 // "old" (ipv4 only) API
 // users: traceroute.c hostname.c - use _list_ of all IPs
 struct hostent *xgethostbyname(const char *name);
diff --git a/ipsvd/tcpudp.c b/ipsvd/tcpudp.c
index 492808a..e46b3c6 100644
--- a/ipsvd/tcpudp.c
+++ b/ipsvd/tcpudp.c
@@ -258,7 +258,7 @@ int tcpudpsvd_main(int argc, char **argv)
 #endif
 
 	if (verbose) {
-		char *addr = xmalloc_sockaddr2dotted(&lsa->sa, sa_len);
+		char *addr = xmalloc_sockaddr2dotted(&lsa->sa);
 		printf("%s: info: listening on %s", applet_name, addr);
 		free(addr);
 #ifndef SSLSVD
@@ -302,7 +302,7 @@ int tcpudpsvd_main(int argc, char **argv)
 	if (max_per_host) {
 		/* Drop connection immediately if cur_per_host > max_per_host
 		 * (minimizing load under SYN flood) */
-		remote_ip = xmalloc_sockaddr2dotted_noport(&remote.sa, sa_len);
+		remote_ip = xmalloc_sockaddr2dotted_noport(&remote.sa);
 		cur_per_host = ipsvd_perhost_add(remote_ip, max_per_host, &hccp);
 		if (cur_per_host > max_per_host) {
 			/* ipsvd_perhost_add detected that max is exceeded
@@ -380,11 +380,11 @@ int tcpudpsvd_main(int argc, char **argv)
 		close(sock);
 
 	if (need_remote_ip)
-		remote_addr = xmalloc_sockaddr2dotted(&remote.sa, sa_len);
+		remote_addr = xmalloc_sockaddr2dotted(&remote.sa);
 
 	if (need_hostnames) {
 		if (option_mask32 & OPT_h) {
-			remote_hostname = xmalloc_sockaddr2host_noport(&remote.sa, sa_len);
+			remote_hostname = xmalloc_sockaddr2host_noport(&remote.sa);
 			if (!remote_hostname) {
 				bb_error_msg("warning: cannot look up hostname for %s", remote_addr);
 				remote_hostname = (char*)"";
@@ -397,9 +397,9 @@ int tcpudpsvd_main(int argc, char **argv)
 			local.len = sa_len;
 			getsockname(0, &local.sa, &local.len);
 		}
-		local_addr = xmalloc_sockaddr2dotted(&local.sa, sa_len);
+		local_addr = xmalloc_sockaddr2dotted(&local.sa);
 		if (!local_hostname) {
-			local_hostname = xmalloc_sockaddr2host_noport(&local.sa, sa_len);
+			local_hostname = xmalloc_sockaddr2host_noport(&local.sa);
 			if (!local_hostname)
 				bb_error_msg_and_die("warning: cannot look up hostname for %s"+9, local_addr);
 		}
@@ -426,7 +426,7 @@ int tcpudpsvd_main(int argc, char **argv)
 		 * an outbond connection to local handler, and it needs
 		 * to know where it originally tried to connect */
 		if (tcp && getsockopt(0, SOL_IP, SO_ORIGINAL_DST, &lsa->sa, &lsa->len) == 0) {
-			char *addr = xmalloc_sockaddr2dotted(&lsa->sa, sa_len);
+			char *addr = xmalloc_sockaddr2dotted(&lsa->sa);
 			xsetenv("TCPORIGDSTADDR", addr);
 			free(addr);
 		}
diff --git a/libbb/xconnect.c b/libbb/xconnect.c
index b90aa9a..cb5ac2c 100644
--- a/libbb/xconnect.c
+++ b/libbb/xconnect.c
@@ -9,9 +9,9 @@
 #include <netinet/in.h>
 #include "libbb.h"
 
-int setsockopt_reuseaddr(int fd)
+void setsockopt_reuseaddr(int fd)
 {
-	return setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &const_int_1, sizeof(const_int_1));
+	setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &const_int_1, sizeof(const_int_1));
 }
 int setsockopt_broadcast(int fd)
 {
@@ -298,11 +298,21 @@ int xconnect_stream(const len_and_sockaddr *lsa)
 /* We hijack this constant to mean something else */
 /* It doesn't hurt because we will add this bit anyway */
 #define IGNORE_PORT NI_NUMERICSERV
-static char* sockaddr2str(const struct sockaddr *sa, socklen_t salen, int flags)
+static char* sockaddr2str(const struct sockaddr *sa, int flags)
 {
 	char host[128];
 	char serv[16];
-	int rc = getnameinfo(sa, salen,
+	int rc;
+	socklen_t salen;
+
+	salen = LSA_SIZEOF_SA;
+#if ENABLE_FEATURE_IPV6
+	if (sa->sa_family == AF_INET)
+		salen = sizeof(struct sockaddr_in);
+	if (sa->sa_family == AF_INET6)
+		salen = sizeof(struct sockaddr_in6);
+#endif
+	rc = getnameinfo(sa, salen,
 			host, sizeof(host),
 	/* can do ((flags & IGNORE_PORT) ? NULL : serv) but why bother? */
 			serv, sizeof(serv),
@@ -327,26 +337,26 @@ static char* sockaddr2str(const struct sockaddr *sa, socklen_t salen, int flags)
 	/*return xstrdup(host);*/
 }
 
-char* xmalloc_sockaddr2host(const struct sockaddr *sa, socklen_t salen)
+char* xmalloc_sockaddr2host(const struct sockaddr *sa)
 {
-	return sockaddr2str(sa, salen, 0);
+	return sockaddr2str(sa, 0);
 }
 
-char* xmalloc_sockaddr2host_noport(const struct sockaddr *sa, socklen_t salen)
+char* xmalloc_sockaddr2host_noport(const struct sockaddr *sa)
 {
-	return sockaddr2str(sa, salen, IGNORE_PORT);
+	return sockaddr2str(sa, IGNORE_PORT);
 }
 
-char* xmalloc_sockaddr2hostonly_noport(const struct sockaddr *sa, socklen_t salen)
+char* xmalloc_sockaddr2hostonly_noport(const struct sockaddr *sa)
 {
-	return sockaddr2str(sa, salen, NI_NAMEREQD | IGNORE_PORT);
+	return sockaddr2str(sa, NI_NAMEREQD | IGNORE_PORT);
 }
-char* xmalloc_sockaddr2dotted(const struct sockaddr *sa, socklen_t salen)
+char* xmalloc_sockaddr2dotted(const struct sockaddr *sa)
 {
-	return sockaddr2str(sa, salen, NI_NUMERICHOST);
+	return sockaddr2str(sa, NI_NUMERICHOST);
 }
 
-char* xmalloc_sockaddr2dotted_noport(const struct sockaddr *sa, socklen_t salen)
+char* xmalloc_sockaddr2dotted_noport(const struct sockaddr *sa)
 {
-	return sockaddr2str(sa, salen, NI_NUMERICHOST | IGNORE_PORT);
+	return sockaddr2str(sa, NI_NUMERICHOST | IGNORE_PORT);
 }
diff --git a/libbb/xfuncs.c b/libbb/xfuncs.c
index 64061e4..5a1090e 100644
--- a/libbb/xfuncs.c
+++ b/libbb/xfuncs.c
@@ -169,13 +169,18 @@ int ndelay_off(int fd)
 	return fcntl(fd, F_SETFL, fcntl(fd,F_GETFL,0) & ~O_NONBLOCK);
 }
 
+void xdup2(int from, int to)
+{
+	if (dup2(from, to) != to)
+		bb_perror_msg_and_die("can't duplicate file descriptor");
+}
+
 // "Renumber" opened fd
 void xmove_fd(int from, int to)
 {
 	if (from == to)
 		return;
-	if (dup2(from, to) != to)
-		bb_perror_msg_and_die("can't duplicate file descriptor");
+	xdup2(from, to);
 	close(from);
 }
 
diff --git a/loginutils/getty.c b/loginutils/getty.c
index 0254d32..8b78856 100644
--- a/loginutils/getty.c
+++ b/loginutils/getty.c
@@ -226,12 +226,6 @@ static void parse_args(int argc, char **argv, struct options *op)
 	debug("exiting parseargs\n");
 }
 
-static void xdup2(int srcfd, int dstfd, const char *tty)
-{
-	if (dup2(srcfd, dstfd) == -1)
-		bb_perror_msg_and_die("%s: dup", tty);
-}
-
 /* open_tty - set up tty as standard { input, output, error } */
 static void open_tty(const char *tty, struct termios *tp, int local)
 {
@@ -255,7 +249,7 @@ static void open_tty(const char *tty, struct termios *tp, int local)
 
 		debug("open(2)\n");
 		fd = xopen(tty, O_RDWR | O_NONBLOCK);
-		xdup2(fd, 0, tty);
+		xdup2(fd, 0);
 		while (fd > 2) close(fd--);
 	} else {
 		/*
@@ -269,8 +263,8 @@ static void open_tty(const char *tty, struct termios *tp, int local)
 
 	/* Replace current standard output/error fd's with new ones */
 	debug("duping\n");
-	xdup2(0, 1, tty);
-	xdup2(0, 2, tty);
+	xdup2(0, 1);
+	xdup2(0, 2);
 
 	/*
 	 * The following ioctl will fail if stdin is not a tty, but also when
diff --git a/networking/dnsd.c b/networking/dnsd.c
index 32166e5..672b729 100644
--- a/networking/dnsd.c
+++ b/networking/dnsd.c
@@ -375,7 +375,7 @@ int dnsd_main(int argc, char **argv)
 	xbind(udps, &lsa->sa, lsa->len);
 	/* xlisten(udps, 50); - ?!! DGRAM sockets are never listened on I think? */
 	bb_info_msg("Accepting UDP packets on %s",
-			xmalloc_sockaddr2dotted(&lsa->sa, lsa->len));
+			xmalloc_sockaddr2dotted(&lsa->sa));
 
 	while (1) {
 		int r;
diff --git a/networking/ftpgetput.c b/networking/ftpgetput.c
index f3d6009..255e413 100644
--- a/networking/ftpgetput.c
+++ b/networking/ftpgetput.c
@@ -348,7 +348,7 @@ int ftpgetput_main(int argc, char **argv)
 	server->lsa = xhost2sockaddr(argv[0], bb_lookup_port(port, "tcp", 21));
 	if (verbose_flag) {
 		printf("Connecting to %s (%s)\n", argv[0],
-			xmalloc_sockaddr2dotted(&server->lsa->sa, server->lsa->len));
+			xmalloc_sockaddr2dotted(&server->lsa->sa));
 	}
 
 	/*  Connect/Setup/Configure the FTP session */
diff --git a/networking/inetd.c b/networking/inetd.c
index 211a8dc..a7517eb 100644
--- a/networking/inetd.c
+++ b/networking/inetd.c
@@ -453,8 +453,7 @@ static void setup(servtab_t *sep)
 		bb_perror_msg("%s/%s: socket", sep->se_service, sep->se_proto);
 		return;
 	}
-	if (setsockopt_reuseaddr(sep->se_fd) < 0)
-		bb_perror_msg("setsockopt(SO_REUSEADDR)");
+	setsockopt_reuseaddr(sep->se_fd);
 
 #if ENABLE_FEATURE_INETD_RPC
 	if (isrpcservice(sep)) {
diff --git a/networking/nc_bloaty.c b/networking/nc_bloaty.c
index 0d10714..30abb3c 100644
--- a/networking/nc_bloaty.c
+++ b/networking/nc_bloaty.c
@@ -278,7 +278,7 @@ static void dolisten(void)
 		rr = getsockname(netfd, &ouraddr->sa, &ouraddr->len);
 		if (rr < 0)
 			bb_perror_msg_and_die("getsockname after bind");
-		addr = xmalloc_sockaddr2dotted(&ouraddr->sa, ouraddr->len);
+		addr = xmalloc_sockaddr2dotted(&ouraddr->sa);
 		fprintf(stderr, "listening on %s ...\n", addr);
 		free(addr);
 	}
@@ -341,7 +341,7 @@ create new one, and bind() it. TODO */
 				/* nc 1.10 bails out instead, and its error message
 				 * is not suppressed by o_verbose */
 				if (o_verbose) {
-					char *remaddr = xmalloc_sockaddr2dotted(&remend.sa, remend.len);
+					char *remaddr = xmalloc_sockaddr2dotted(&remend.sa);
 					bb_error_msg("connect from wrong ip/port %s ignored", remaddr);
 					free(remaddr);
 				}
@@ -393,9 +393,9 @@ create new one, and bind() it. TODO */
 	 accept the connection and then reject undesireable ones by closing.
 	 In other words, we need a TCP MSG_PEEK. */
 	/* bbox: removed most of it */
-		lcladdr = xmalloc_sockaddr2dotted(&ouraddr->sa, ouraddr->len);
-		remaddr = xmalloc_sockaddr2dotted(&remend.sa, remend.len);
-		remhostname = o_nflag ? remaddr : xmalloc_sockaddr2host(&remend.sa, remend.len);
+		lcladdr = xmalloc_sockaddr2dotted(&ouraddr->sa);
+		remaddr = xmalloc_sockaddr2dotted(&remend.sa);
+		remhostname = o_nflag ? remaddr : xmalloc_sockaddr2host(&remend.sa);
 		fprintf(stderr, "connect to %s from %s (%s)\n",
 				lcladdr, remhostname, remaddr);
 		free(lcladdr);
@@ -796,7 +796,7 @@ int nc_main(int argc, char **argv)
 
 		remend = *themaddr;
 		if (o_verbose)
-			themdotted = xmalloc_sockaddr2dotted(&themaddr->sa, themaddr->len);
+			themdotted = xmalloc_sockaddr2dotted(&themaddr->sa);
 
 		x = connect_w_timeout(netfd);
 		if (o_zero && x == 0 && o_udpmode)        /* if UDP scanning... */
diff --git a/networking/netstat.c b/networking/netstat.c
index 014e5e2..9fd3d2f 100644
--- a/networking/netstat.c
+++ b/networking/netstat.c
@@ -140,8 +140,8 @@ static char *ip_port_str(struct sockaddr *addr, int port, const char *proto, int
 	/* Code which used "*" for INADDR_ANY is removed: it's ambiguous in IPv6,
 	 * while "0.0.0.0" is not. */
 
-	host = numeric ? xmalloc_sockaddr2dotted_noport(addr, salen)
-	               : xmalloc_sockaddr2host_noport(addr, salen);
+	host = numeric ? xmalloc_sockaddr2dotted_noport(addr)
+	               : xmalloc_sockaddr2host_noport(addr);
 
 	host_port = xasprintf("%s:%s", host, get_sname(htons(port), proto, numeric));
 	free(host);
diff --git a/networking/nslookup.c b/networking/nslookup.c
index 608e654..0036d0d 100644
--- a/networking/nslookup.c
+++ b/networking/nslookup.c
@@ -72,8 +72,8 @@ static int print_host(const char *hostname, const char *header)
 		// printf("%s\n", cur->ai_canonname); ?
 		while (cur) {
 			char *dotted, *revhost;
-			dotted = xmalloc_sockaddr2dotted_noport(cur->ai_addr, cur->ai_addrlen);
-			revhost = xmalloc_sockaddr2hostonly_noport(cur->ai_addr, cur->ai_addrlen);
+			dotted = xmalloc_sockaddr2dotted_noport(cur->ai_addr);
+			revhost = xmalloc_sockaddr2hostonly_noport(cur->ai_addr);
 
 			printf("Address %u: %s%c", ++cnt, dotted, revhost ? ' ' : '\n');
 			if (revhost) {
@@ -102,8 +102,7 @@ static void server_print(void)
 {
 	char *server;
 
-	server = xmalloc_sockaddr2dotted_noport((struct sockaddr*)&_res.nsaddr_list[0],
-			sizeof(struct sockaddr_in));
+	server = xmalloc_sockaddr2dotted_noport((struct sockaddr*)&_res.nsaddr_list[0]);
 	/* I honestly don't know what to do if DNS server has _IPv6 address_.
 	 * Probably it is listed in
 	 * _res._u._ext_.nsaddrs[MAXNS] (of type "struct sockaddr_in6*" each)
diff --git a/networking/ping.c b/networking/ping.c
index 127474c..d1a413d 100644
--- a/networking/ping.c
+++ b/networking/ping.c
@@ -664,7 +664,7 @@ static void ping(len_and_sockaddr *lsa)
 	printf("PING %s (%s)", hostname, dotted);
 	if (source_lsa) {
 		printf(" from %s",
-			xmalloc_sockaddr2dotted_noport(&source_lsa->sa, source_lsa->len));
+			xmalloc_sockaddr2dotted_noport(&source_lsa->sa));
 	}
 	printf(": %d data bytes\n", datalen);
 
@@ -715,7 +715,7 @@ int ping_main(int argc, char **argv)
 		/* leaking it here... */
 		source_lsa = NULL;
 
-	dotted = xmalloc_sockaddr2dotted_noport(&lsa->sa, lsa->len);
+	dotted = xmalloc_sockaddr2dotted_noport(&lsa->sa);
 	ping(lsa);
 	pingstats(0);
 	return EXIT_SUCCESS;
diff --git a/networking/tftp.c b/networking/tftp.c
index 85d1a85..030c011 100644
--- a/networking/tftp.c
+++ b/networking/tftp.c
@@ -443,7 +443,7 @@ int tftp_main(int argc, char **argv)
 
 #if ENABLE_DEBUG_TFTP
 	fprintf(stderr, "using server '%s', remotefile '%s', localfile '%s'\n",
-			xmalloc_sockaddr2dotted(&peer_lsa->sa, peer_lsa->len),
+			xmalloc_sockaddr2dotted(&peer_lsa->sa),
 			remotefile, localfile);
 #endif
 
diff --git a/networking/traceroute.c b/networking/traceroute.c
index 20f304d..0923d97 100644
--- a/networking/traceroute.c
+++ b/networking/traceroute.c
@@ -812,7 +812,7 @@ print_inetname(struct sockaddr_in *from)
 	else {
 		char *n = NULL;
 		if (from->sin_addr.s_addr != INADDR_ANY)
-			n = xmalloc_sockaddr2host_noport((struct sockaddr*)from, sizeof(*from));
+			n = xmalloc_sockaddr2host_noport((struct sockaddr*)from);
 		printf(" %s (%s)", (n ? n : ina), ina);
 		free(n);
 	}
diff --git a/networking/udhcp/common.h b/networking/udhcp/common.h
index bc21176..33417af 100644
--- a/networking/udhcp/common.h
+++ b/networking/udhcp/common.h
@@ -83,7 +83,7 @@ int udhcp_sp_fd_set(fd_set *rfds, int extra_fd);
 int udhcp_sp_read(fd_set *rfds);
 int raw_socket(int ifindex);
 int read_interface(const char *interface, int *ifindex, uint32_t *addr, uint8_t *arp);
-int listen_socket(uint32_t ip, int port, const char *inf);
+int listen_socket(/*uint32_t ip,*/ int port, const char *inf);
 /* Returns 1 if no reply received */
 int arpping(uint32_t test_ip, uint32_t from_ip, uint8_t *from_mac, const char *interface);
 
diff --git a/networking/udhcp/dhcpc.c b/networking/udhcp/dhcpc.c
index 7d38742..f0a3351 100644
--- a/networking/udhcp/dhcpc.c
+++ b/networking/udhcp/dhcpc.c
@@ -311,7 +311,7 @@ int udhcpc_main(int argc, char **argv)
 
 		if (listen_mode != LISTEN_NONE && sockfd < 0) {
 			if (listen_mode == LISTEN_KERNEL)
-				sockfd = listen_socket(INADDR_ANY, CLIENT_PORT, client_config.interface);
+				sockfd = listen_socket(/*INADDR_ANY,*/ CLIENT_PORT, client_config.interface);
 			else
 				sockfd = raw_socket(client_config.ifindex);
 		}
diff --git a/networking/udhcp/dhcpd.c b/networking/udhcp/dhcpd.c
index fb42e2f..2fd16ce 100644
--- a/networking/udhcp/dhcpd.c
+++ b/networking/udhcp/dhcpd.c
@@ -95,7 +95,7 @@ int udhcpd_main(int argc, char **argv)
 	while (1) { /* loop until universe collapses */
 
 		if (server_socket < 0) {
-			server_socket = listen_socket(INADDR_ANY, SERVER_PORT,
+			server_socket = listen_socket(/*INADDR_ANY,*/ SERVER_PORT,
 					server_config.interface);
 		}
 
diff --git a/networking/udhcp/dhcprelay.c b/networking/udhcp/dhcprelay.c
index 4ed65a2..3e1758d 100644
--- a/networking/udhcp/dhcprelay.c
+++ b/networking/udhcp/dhcprelay.c
@@ -167,16 +167,17 @@ static int init_sockets(char **client, int num_clients,
 	int i;
 
 	/* talk to real server on bootps */
-	fds[0] = listen_socket(htonl(INADDR_ANY), 67, server);
+	fds[0] = listen_socket(/*INADDR_ANY,*/ 67, server);
 	*max_socket = fds[0];
 
 	/* array starts at 1 since server is 0 */
 	num_clients++;
 
-	for (i=1; i < num_clients; i++) {
+	for (i = 1; i < num_clients; i++) {
 		/* listen for clients on bootps */
-		fds[i] = listen_socket(htonl(INADDR_ANY), 67, client[i-1]);
-		if (fds[i] > *max_socket) *max_socket = fds[i];
+		fds[i] = listen_socket(/*NADDR_ANY,*/ 67, client[i-1]);
+		if (fds[i] > *max_socket)
+			*max_socket = fds[i];
 	}
 
 	return i;
diff --git a/networking/udhcp/packet.c b/networking/udhcp/packet.c
index 272e79d..41cd321 100644
--- a/networking/udhcp/packet.c
+++ b/networking/udhcp/packet.c
@@ -194,17 +194,14 @@ int udhcp_kernel_packet(struct dhcpMessage *payload,
 	if (fd < 0)
 		return -1;
 
-	if (setsockopt_reuseaddr(fd) == -1) {
-		close(fd);
-		return -1;
-	}
+	setsockopt_reuseaddr(fd);
 
 	memset(&client, 0, sizeof(client));
 	client.sin_family = AF_INET;
 	client.sin_port = htons(source_port);
 	client.sin_addr.s_addr = source_ip;
 
-	if (bind(fd, (struct sockaddr *)&client, sizeof(struct sockaddr)) == -1) {
+	if (bind(fd, (struct sockaddr *)&client, sizeof(client)) == -1) {
 		close(fd);
 		return -1;
 	}
diff --git a/networking/udhcp/socket.c b/networking/udhcp/socket.c
index 1e62f8e..79ddfb1 100644
--- a/networking/udhcp/socket.c
+++ b/networking/udhcp/socket.c
@@ -45,10 +45,6 @@ int read_interface(const char *interface, int *ifindex, uint32_t *addr, uint8_t
 
 	memset(&ifr, 0, sizeof(ifr));
 	fd = xsocket(AF_INET, SOCK_RAW, IPPROTO_RAW);
-//	if (fd < 0) {
-//		bb_perror_msg("socket failed");
-//		return -1;
-//	}
 
 	ifr.ifr_addr.sa_family = AF_INET;
 	strncpy(ifr.ifr_name, interface, sizeof(ifr.ifr_name));
@@ -87,40 +83,30 @@ int read_interface(const char *interface, int *ifindex, uint32_t *addr, uint8_t
 	return 0;
 }
 
-
-int listen_socket(uint32_t ip, int port, const char *inf)
+/* 1. None of the callers expects it to ever fail */
+/* 2. ip was always INADDR_ANY */
+int listen_socket(/*uint32_t ip,*/ int port, const char *inf)
 {
-	struct ifreq interface;
 	int fd;
+	struct ifreq interface;
 	struct sockaddr_in addr;
 
 	DEBUG("Opening listen socket on 0x%08x:%d %s", ip, port, inf);
 	fd = xsocket(PF_INET, SOCK_DGRAM, IPPROTO_UDP);
 
-	memset(&addr, 0, sizeof(addr));
-	addr.sin_family = AF_INET;
-	addr.sin_port = htons(port);
-	addr.sin_addr.s_addr = ip;
-
-	if (setsockopt_reuseaddr(fd) == -1) {
-		close(fd);
-		return -1;
-	}
-	if (setsockopt_broadcast(fd) == -1) {
-		close(fd);
-		return -1;
-	}
+	setsockopt_reuseaddr(fd);
+	if (setsockopt_broadcast(fd) == -1)
+		bb_perror_msg_and_die("SO_BROADCAST");
 
 	strncpy(interface.ifr_name, inf, IFNAMSIZ);
-	if (setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, &interface, sizeof(interface)) < 0) {
-		close(fd);
-		return -1;
-	}
+	if (setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, &interface, sizeof(interface)) == -1)
+		bb_perror_msg_and_die("SO_BINDTODEVICE");
 
-	if (bind(fd, (struct sockaddr *)&addr, sizeof(addr)) == -1) {
-		close(fd);
-		return -1;
-	}
+	memset(&addr, 0, sizeof(addr));
+	addr.sin_family = AF_INET;
+	addr.sin_port = htons(port);
+	/* addr.sin_addr.s_addr = ip; - all-zeros is INADDR_ANY */
+	xbind(fd, (struct sockaddr *)&addr, sizeof(addr));
 
 	return fd;
 }
diff --git a/networking/wget.c b/networking/wget.c
index d90368c..3e61ea6 100644
--- a/networking/wget.c
+++ b/networking/wget.c
@@ -236,7 +236,7 @@ int wget_main(int argc, char **argv)
 	lsa = xhost2sockaddr(server.host, server.port);
 	if (!(opt & WGET_OPT_QUIET)) {
 		fprintf(stderr, "Connecting to %s (%s)\n", server.host,
-				xmalloc_sockaddr2dotted(&lsa->sa, lsa->len));
+				xmalloc_sockaddr2dotted(&lsa->sa));
 		/* We leak result of xmalloc_sockaddr2dotted */
 	}
 
diff --git a/runit/runsv.c b/runit/runsv.c
index 20f8495..f70b513 100644
--- a/runit/runsv.c
+++ b/runit/runsv.c
@@ -313,14 +313,11 @@ static void startservice(struct svdir *s)
 		/* child */
 		if (haslog) {
 			if (s->islog) {
-				if (dup2(logpipe[0], 0) == -1)
-					fatal_cannot("setup filedescriptor for ./log/run");
+				xdup2(logpipe[0], 0);
 				close(logpipe[1]);
-				if (chdir("./log") == -1)
-					fatal_cannot("change directory to ./log");
+				xchdir("./log");
 			} else {
-				if (dup2(logpipe[1], 1) == -1)
-					fatal_cannot("setup filedescriptor for ./run");
+				xdup2(logpipe[1], 1);
 				close(logpipe[0]);
 			}
 		}
diff --git a/util-linux/mount.c b/util-linux/mount.c
index c159f41..bd7ecc2 100644
--- a/util-linux/mount.c
+++ b/util-linux/mount.c
@@ -1413,7 +1413,7 @@ static int singlemount(struct mntent *mp, int ignore_busy)
 
 		// insert ip=... option into string flags.
 
-		dotted = xmalloc_sockaddr2dotted_noport(&lsa->sa, lsa->len);
+		dotted = xmalloc_sockaddr2dotted_noport(&lsa->sa);
 		ip = xasprintf("ip=%s", dotted);
 		parse_mount_options(ip, &filteropts);