Replace malloc / memset / select song and dance with poll(2) like

ping6.
Prompted by and initial diff from Peter Malone (peter _AT_
petermalone _DOT_ org), thanks!
OK jca@

diff --git a/sbin/ping/ping.c b/sbin/ping/ping.c
index 6a13a86..b6f18be 100644 (file)
--- a/sbin/ping/ping.c
+++ b/sbin/ping/ping.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: ping.c,v 1.100 2014/03/24 11:11:49 mpi Exp $  */
+/*     $OpenBSD: ping.c,v 1.101 2014/04/23 12:27:31 florian Exp $      */
 /*     $NetBSD: ping.c,v 1.20 1995/08/11 22:37:58 cgd Exp $    */
 
 /*
@@ -70,6 +70,7 @@
 #include <ctype.h>
 #include <err.h>
 #include <errno.h>
+#include <poll.h>
 #include <string.h>
 #include <stdlib.h>
 
@@ -175,11 +176,12 @@ void usage(void);
 int
 main(int argc, char *argv[])
 {
-       struct timeval timeout;
        struct hostent *hp;
        struct sockaddr_in *to;
+       struct pollfd fdmaskp[1];
        struct in_addr saddr;
        int i, ch, hold = 1, packlen, preload, maxsize, df = 0, tos = 0;
+       int timeout;
        u_char *datap, *packet, ttl = MAXTTL, loop = 1;
        char *target, hnamebuf[MAXHOSTNAMELEN];
 #ifdef IP_OPTIONS
@@ -187,8 +189,6 @@ main(int argc, char *argv[])
 #endif
        socklen_t maxsizelen;
        const char *errstr;
-       fd_set *fdmaskp;
-       size_t fdmasks;
        uid_t uid;
        u_int rtableid;
 
@@ -507,10 +507,6 @@ main(int argc, char *argv[])
        if ((options & F_FLOOD) == 0)
                catcher(0);             /* start things going */
 
-       fdmasks = howmany(s+1, NFDBITS) * sizeof(fd_mask);
-       if ((fdmaskp = (fd_set *)malloc(fdmasks)) == NULL)
-               err(1, "malloc");
-
        for (;;) {
                struct sockaddr_in from;
                sigset_t omask, nmask;
@@ -519,14 +515,20 @@ main(int argc, char *argv[])
 
                if (options & F_FLOOD) {
                        pinger();
-                       timeout.tv_sec = 0;
-                       timeout.tv_usec = 10000;
-                       memset(fdmaskp, 0, fdmasks);
-                       FD_SET(s, fdmaskp);
-                       if (select(s + 1, (fd_set *)fdmaskp, (fd_set *)NULL,
-                           (fd_set *)NULL, &timeout) < 1)
-                               continue;
-               }
+                       timeout = 10;
+               } else
+                       timeout = INFTIM;
+               fdmaskp[0].fd = s;
+               fdmaskp[0].events = POLLIN;
+               cc = poll(fdmaskp, 1, timeout);
+               if (cc < 0) {
+                       if (errno != EINTR) {
+                               warn("poll");
+                               sleep(1);
+                       }
+                       continue;
+               } else if (cc == 0)
+                       continue;
                fromlen = sizeof(from);
                if ((cc = recvfrom(s, packet, packlen, 0,
                    (struct sockaddr *)&from, &fromlen)) < 0) {
@@ -543,7 +545,6 @@ main(int argc, char *argv[])
                if (npackets && nreceived >= npackets)
                        break;
        }
-       free(fdmaskp);
        finish(0);
        /* NOTREACHED */
        exit(0);        /* Make the compiler happy */