Fix sequence number byte order mismatch.

Reference: /n/sources/patch/applied/ping-byteorder-fix
Date: Fri Dec 23 12:21:46 CET 2005

--- /sys/src/cmd/ip/ping.c	Fri Dec 23 12:21:25 2005
+++ /sys/src/cmd/ip/ping.c	Fri Dec 23 12:21:20 2005
@@ -81,8 +81,6 @@
 	USED(a);
 	if(strstr(msg, "alarm"))
 		noted(NCONT);
-	else if(strstr(msg, "die"))
-		exits("errors");
 	else
 		noted(NDFLT);
 }
@@ -96,7 +94,7 @@
 	for(l = &first; *l; ){
 		r = *l;
 
-		if(ip && r->seq == seq){
+		if(r->seq == seq){
 			r->rtt = now-r->time;
 			r->ttl = ip->ttl;
 			reply(r, ip);
@@ -105,8 +103,7 @@
 		if(now-r->time > MINUTE){
 			*l = r->next;
 			r->rtt = now-r->time;
-			if(ip)
-				r->ttl = ip->ttl;
+			r->ttl = ip->ttl;
 			if(r->replied == 0)
 				lost(r, ip);
 			free(r);
@@ -144,8 +141,7 @@
 		}
 		r = malloc(sizeof *r);
 		if(r != nil){
-			ip->seq[0] = seq;
-			ip->seq[1] = seq>>8;
+			hnputs(ip->seq, seq);
 			r->seq = seq;
 			r->next = nil;
 			lock(&listlock);
@@ -168,7 +164,7 @@
 }
 
 void
-rcvr(int fd, int msglen, int interval, int nmsg)
+rcvr(int fd, int msglen, int interval, int nmsg, int senderpid)
 {
 	uchar buf[64*1024+512];
 	Icmp *ip;
@@ -180,15 +176,14 @@
 	ip = (Icmp*)buf;
 	sum = 0;
 
-	while(lostmsgs+rcvdmsgs < nmsg){
+	while(!done || first != nil){
 		alarm((nmsg-lostmsgs-rcvdmsgs)*interval+5000);
 		n = read(fd, buf, sizeof(buf));
 		alarm(0);
 		now = nsec();
-		if(n <= 0){	/* read interrupted - time to go */
-fprint(2, "clean\n");
-			clean(0, now+MINUTE, nil);
-			continue;
+		if(n <= 0){
+			print("read: %r\n");
+			break;
 		}
 		if(n < msglen){
 			print("bad len %d/%d\n", n, msglen);
@@ -200,7 +195,7 @@
 				munged++;
 		if(munged)
 			print("currupted reply\n");
-		x = (ip->seq[1]<<8)|ip->seq[0];
+		x = nhgets(ip->seq);
 		if(ip->type != EchoReply || ip->code != 0) {
 			print("bad sequence/code/type %d/%d/%d\n",
 				ip->type, ip->code, x);
@@ -217,6 +212,7 @@
 
 	if(lostmsgs)
 		print("%d out of %d messages lost\n", lostmsgs, lostmsgs+rcvdmsgs);
+	postnote(PNPROC, senderpid, "die");
 }
 
 void
@@ -231,6 +227,7 @@
 {
 	int fd;
 	int msglen, interval, nmsg;
+	int pid;
 
 	nsec();		/* make sure time file is already open */
 
@@ -284,11 +281,12 @@
 
 	print("sending %d %d byte messages %d ms apart\n", nmsg, msglen, interval);
 
+	pid = getpid();
 	switch(rfork(RFPROC|RFMEM|RFFDG)){
 	case -1:
 		fprint(2, "%s: can't fork: %r\n", argv0);
 	case 0:
-		rcvr(fd, msglen, interval, nmsg);
+		rcvr(fd, msglen, interval, nmsg, pid);
 		exits(0);
 	default:
 		sender(fd, msglen, interval, nmsg);
@@ -300,10 +298,9 @@
 void
 reply(Req *r, Icmp *ip)
 {
+	rcvdmsgs++;
 	r->rtt /= 1000LL;
 	sum += r->rtt;
-	if(!r->replied)
-		rcvdmsgs++;
 	if(!quiet && !lostonly){
 		if(addresses)
 			print("%ud: %V->%V rtt %lld µs, avg rtt %lld µs, ttl = %d\n",
@@ -323,11 +320,14 @@
 {
 	if(!quiet){
 		if(addresses)
-			print("lost %ud: %V->%V\n", r->seq-firstseq,
-				ip->src, ip->dst);
+			print("lost %ud: %V->%V avg rtt %lld µs\n",
+				r->seq-firstseq,
+				ip->src, ip->dst,
+				sum/rcvdmsgs);
 		else
-			print("lost %ud\n", r->seq-firstseq);
+			print("lost %ud: avg rtt %lld µs\n",
+				r->seq-firstseq,
+				sum/rcvdmsgs);
 	}
 	lostmsgs++;
 }
-