Add netstat(1) knob to reset net.inet.{ip|icmp|tcp|udp|igmp}.stats.

For example, ``netstat -s -p ip -z'' will show and reset IP stats.

PR:		bin/17338

4 files changed, 37 insertions, 13 deletions

diff --git a/usr.bin/netstat/inet.c b/usr.bin/netstat/inet.c
index 723ec5b..594ab7f 100644
--- a/usr.bin/netstat/inet.c
+++ b/usr.bin/netstat/inet.c
@@ -348,10 +348,13 @@ protopr(u_long proto,		/* for sysctl version we pass proto # */
 void
 tcp_stats(u_long off __unused, char *name, int af __unused)
 {
-	struct tcpstat tcpstat;
+	struct tcpstat tcpstat, zerostat;
 	size_t len = sizeof tcpstat;
 	
-	if (sysctlbyname("net.inet.tcp.stats", &tcpstat, &len, 0, 0) < 0) {
+	if (zflag)
+		memset(&zerostat, 0, len);
+	if (sysctlbyname("net.inet.tcp.stats", &tcpstat, &len,
+	    zflag ? &zerostat : NULL, zflag ? len : 0) < 0) {
 		warn("sysctl: net.inet.tcp.stats");
 		return;
 	}
@@ -446,11 +449,14 @@ tcp_stats(u_long off __unused, char *name, int af __unused)
 void
 udp_stats(u_long off __unused, char *name, int af __unused)
 {
-	struct udpstat udpstat;
+	struct udpstat udpstat, zerostat;
 	size_t len = sizeof udpstat;
 	u_long delivered;
 
-	if (sysctlbyname("net.inet.udp.stats", &udpstat, &len, 0, 0) < 0) {
+	if (zflag)
+		memset(&zerostat, 0, len);
+	if (sysctlbyname("net.inet.udp.stats", &udpstat, &len,
+	    zflag ? &zerostat : NULL, zflag ? len : 0) < 0) {
 		warn("sysctl: net.inet.udp.stats");
 		return;
 	}
@@ -497,10 +503,13 @@ udp_stats(u_long off __unused, char *name, int af __unused)
 void
 ip_stats(u_long off __unused, char *name, int af __unused)
 {
-	struct ipstat ipstat;
+	struct ipstat ipstat, zerostat;
 	size_t len = sizeof ipstat;
 
-	if (sysctlbyname("net.inet.ip.stats", &ipstat, &len, 0, 0) < 0) {
+	if (zflag)
+		memset(&zerostat, 0, len);
+	if (sysctlbyname("net.inet.ip.stats", &ipstat, &len,
+	    zflag ? &zerostat : NULL, zflag ? len : 0) < 0) {
 		warn("sysctl: net.inet.ip.stats");
 		return;
 	}
@@ -577,7 +586,7 @@ static	char *icmpnames[] = {
 void
 icmp_stats(u_long off __unused, char *name, int af __unused)
 {
-	struct icmpstat icmpstat;
+	struct icmpstat icmpstat, zerostat;
 	int i, first;
 	int mib[4];		/* CTL_NET + PF_INET + IPPROTO_ICMP + req */
 	size_t len;
@@ -588,9 +597,13 @@ icmp_stats(u_long off __unused, char *name, int af __unused)
 	mib[3] = ICMPCTL_STATS;
 
 	len = sizeof icmpstat;
-	memset(&icmpstat, 0, len);
-	if (sysctl(mib, 4, &icmpstat, &len, (void *)0, 0) < 0)
-		return;		/* XXX should complain, but not traditional */
+	if (zflag)
+		memset(&zerostat, 0, len);
+	if (sysctl(mib, 4, &icmpstat, &len,
+	    zflag ? &zerostat : NULL, zflag ? len : 0) < 0) {
+		warn("sysctl: net.inet.icmp.stats");
+		return;
+	}
 
 	printf("%s:\n", name);
 
@@ -643,10 +656,13 @@ icmp_stats(u_long off __unused, char *name, int af __unused)
 void
 igmp_stats(u_long off __unused, char *name, int af __unused)
 {
-	struct igmpstat igmpstat;
+	struct igmpstat igmpstat, zerostat;
 	size_t len = sizeof igmpstat;
 
-	if (sysctlbyname("net.inet.igmp.stats", &igmpstat, &len, 0, 0) < 0) {
+	if (zflag)
+		memset(&zerostat, 0, len);
+	if (sysctlbyname("net.inet.igmp.stats", &igmpstat, &len,
+	    zflag ? &zerostat : NULL, zflag ? len : 0) < 0) {
 		warn("sysctl: net.inet.igmp.stats");
 		return;
 	}
diff --git a/usr.bin/netstat/main.c b/usr.bin/netstat/main.c
index 15736f9..d2417de 100644
--- a/usr.bin/netstat/main.c
+++ b/usr.bin/netstat/main.c
@@ -330,6 +330,7 @@ int	rflag;		/* show routing tables (or routing stats) */
 int	sflag;		/* show protocol statistics */
 int	tflag;		/* show i/f watchdog timers */
 int	Wflag;		/* wide display */
+int	zflag;		/* zero stats */
 
 int	interval;	/* repeat interval for i/f stats */
 
@@ -348,7 +349,7 @@ main(argc, argv)
 
 	af = AF_UNSPEC;
 
-	while ((ch = getopt(argc, argv, "Aabdf:gI:iLlM:mN:np:rSstuWw:")) != -1)
+	while ((ch = getopt(argc, argv, "Aabdf:gI:iLlM:mN:np:rSstuWw:z")) != -1)
 		switch(ch) {
 		case 'A':
 			Aflag = 1;
@@ -458,6 +459,9 @@ main(argc, argv)
 			interval = atoi(optarg);
 			iflag = 1;
 			break;
+		case 'z':
+			zflag = 1;
+			break;
 		case '?':
 		default:
 			usage();
diff --git a/usr.bin/netstat/netstat.1 b/usr.bin/netstat/netstat.1
index 667c29f..9209628 100644
--- a/usr.bin/netstat/netstat.1
+++ b/usr.bin/netstat/netstat.1
@@ -57,6 +57,7 @@
 .Op Fl N Ar system
 .Nm
 .Fl s Op Fl s
+.Op Fl z
 .Op Fl f Ar address_family | Fl p Ar protocol
 .Op Fl M Ar core
 .Op Fl N Ar system
@@ -272,6 +273,8 @@ some fields to overflow.
 Show network interface statistics at intervals of
 .Ar wait
 seconds.
+.It Fl z
+Reset statistics.
 .El
 .Pp
 The default display, for active sockets, shows the local
diff --git a/usr.bin/netstat/netstat.h b/usr.bin/netstat/netstat.h
index fffcfd6..f4411e6 100644
--- a/usr.bin/netstat/netstat.h
+++ b/usr.bin/netstat/netstat.h
@@ -51,6 +51,7 @@ extern int	rflag;	/* show routing tables (or routing stats) */
 extern int	sflag;	/* show protocol statistics */
 extern int	tflag;	/* show i/f watchdog timers */
 extern int	Wflag;	/* wide display */
+extern int	zflag;	/* zero stats */
 
 extern int	interval; /* repeat interval for i/f stats */