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

16 files changed, 43 insertions, 61 deletions

diff --git a/networking/dnsd.c b/networking/dnsd.c
index 32166e555..672b729e0 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 f3d6009dd..255e413cb 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 211a8dcbf..a7517ebdf 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 0d1071499..30abb3c1c 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 014e5e251..9fd3d2f86 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 608e65462..0036d0d17 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 127474ccc..d1a413dd3 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 85d1a857f..030c0116e 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 20f304d53..0923d97dc 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 bc21176a5..33417af09 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 7d38742b9..f0a3351fd 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 fb42e2f73..2fd16ce9b 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 4ed65a2d6..3e1758d5c 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 272e79df1..41cd32135 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 1e62f8e40..79ddfb1e2 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 d90368c40..3e61ea656 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 */
 	}