*: replace select-for-one descriptor with poll, it's smaller.

$ ./.cmk bloatcheck
function                                             old     new   delta
readit                                               406     364     -42
syslogd_main                                        1249    1206     -43
traceroute_main                                     4115    4060     -55
mysleep                                              112      45     -67
arpping                                              579     441    -138
tftp                                                1575    1182    -393
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/6 up/down: 0/-738)           Total: -738 bytes
   text    data     bss     dec     hex filename
 770580    1051   10764  782395   bf03b busybox_old
 769820    1051   10764  781635   bed43 busybox_unstripped

1 files changed, 9 insertions, 15 deletions

diff --git a/networking/traceroute.c b/networking/traceroute.c
index 236ddbd..21921e5 100644
--- a/networking/traceroute.c
+++ b/networking/traceroute.c
@@ -346,10 +346,10 @@ static int optlen;                     /* length of ip options */
 
 
 struct globals {
-	/* last inbound (icmp) packet */
-	unsigned char packet[512];
 	struct sockaddr_storage whereto;        /* Who to try to reach */
 	struct sockaddr_storage wherefrom;      /* Who we are */
+	/* last inbound (icmp) packet */
+	unsigned char packet[512];
 #if ENABLE_FEATURE_TRACEROUTE_SOURCE_ROUTE
 	/* Maximum number of gateways (include room for one noop) */
 #define NGATEWAYS ((int)((MAX_IPOPTLEN - IPOPT_MINOFF - 1) / sizeof(uint32_t)))
@@ -359,7 +359,7 @@ struct globals {
 };
 
 #define G (*ptr_to_globals)
-
+#define INIT_G() PTR_TO_GLOBALS = xzalloc(sizeof(G))
 #define packet    (G.packet   )
 #define whereto   (G.whereto  )
 #define wherefrom (G.wherefrom)
@@ -537,21 +537,15 @@ findsaddr(const struct sockaddr_in *to, struct sockaddr_in *from)
 static int
 wait_for_reply(int sock, struct sockaddr_in *fromp)
 {
-	fd_set fds;
-	struct timeval tvwait;
+	struct pollfd pfd[1];
 	int cc = 0;
 	socklen_t fromlen = sizeof(*fromp);
 
-	FD_ZERO(&fds);
-	FD_SET(sock, &fds);
-
-	tvwait.tv_sec = waittime;
-	tvwait.tv_usec = 0;
-
-	if (select(sock + 1, &fds, NULL, NULL, &tvwait) > 0)
-		cc = recvfrom(sock, (char *)packet, sizeof(packet), 0,
+	pfd[0].fd = sock;
+	pfd[0].events = POLLIN;
+	if (poll(pfd, 1, waittime * 1000) > 0)
+		cc = recvfrom(sock, packet, sizeof(packet), 0,
 			    (struct sockaddr *)fromp, &fromlen);
-
 	return cc;
 }
 
@@ -930,7 +924,7 @@ int traceroute_main(int argc, char **argv)
 	llist_t *source_route_list = NULL;
 #endif
 
-	PTR_TO_GLOBALS = xzalloc(sizeof(G));
+	INIT_G();
 	from = (struct sockaddr_in *)&wherefrom;
 	to = (struct sockaddr_in *)&whereto;