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

1 files changed, 14 insertions, 28 deletions

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;
 }