Add support, under FreeBSD, for the BINTIME option which gets us

nanosecond accurracy for packet timestamps.  There is of course
variation in the kernel but we can do better than the original
microsecond version.

src/dep/net.c

@@ -391,13 +391,23 @@ netInit(NetPath * netPath, RunTimeOpts * rtOpts, PtpClock * ptpClock)
 	}
 	/* make timestamps available through recvmsg() */
 	temp = 1;
+#if defined(linux)
 	if (setsockopt(netPath->eventSock, SOL_SOCKET, SO_TIMESTAMP, 
 		       &temp, sizeof(int)) < 0
 	    || setsockopt(netPath->generalSock, SOL_SOCKET, SO_TIMESTAMP, 
 			  &temp, sizeof(int)) < 0) {
 		PERROR("failed to enable receive time stamps");
 		return FALSE;
 	}
+#else /* FreeBSD */
+	if (setsockopt(netPath->eventSock, SOL_SOCKET, SO_BINTIME, 
+		       &temp, sizeof(int)) < 0
+	    || setsockopt(netPath->generalSock, SOL_SOCKET, SO_BINTIME, 
+			  &temp, sizeof(int)) < 0) {
+		PERROR("failed to enable receive time stamps");
+		return FALSE;
+	}
+#endif
 	return TRUE;
 }
 
@@ -464,7 +474,11 @@ netRecvEvent(Octet * buf, TimeInternal * time, NetPath * netPath)
 	}     cmsg_un;
 
 	struct cmsghdr *cmsg;
+#if defined(linux)
 	struct timeval *tv;
+#else
+	struct timespec ts;
+#endif
 
 	vec[0].iov_base = buf;
 	vec[0].iov_len = PACKET_SIZE;
@@ -508,6 +522,7 @@ netRecvEvent(Octet * buf, TimeInternal * time, NetPath * netPath)
 
 		return 0;
 	}
+#if defined(linux)
 	tv = 0;
 	for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL; 
 	     cmsg = CMSG_NXTHDR(&msg, cmsg)) {
@@ -521,6 +536,21 @@ netRecvEvent(Octet * buf, TimeInternal * time, NetPath * netPath)
 		time->nanoseconds = tv->tv_usec * 1000;
 		DBGV("kernel recv time stamp %us %dns\n", 
 		     time->seconds, time->nanoseconds);
+#else /* FreeBSD has more accurate time stamps */
+	bzero(&ts, sizeof(ts));
+	for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL; 
+	     cmsg = CMSG_NXTHDR(&msg, cmsg)) {
+		if (cmsg->cmsg_level == SOL_SOCKET && 
+		    cmsg->cmsg_type == SCM_BINTIME)
+			bintime2timespec((struct bintime *)CMSG_DATA(cmsg),
+					 &ts);
+	}
+
+	if (ts.tv_sec != 0) {
+		time->seconds = ts.tv_sec;
+		time->nanoseconds = ts.tv_nsec;
+		DBGV("kernel recv time stamp %us %dns\n", time->seconds, time->nanoseconds);
+#endif /* Linux or FreeBSD */
 	} else {
 		/*
 		 * do not try to get by with recording the time here, better
@@ -563,8 +593,11 @@ netRecvGeneral(Octet * buf, TimeInternal * time, NetPath * netPath)
 	}     cmsg_un;
 
 	struct cmsghdr *cmsg;
+#if defined(linux)
 	struct timeval *tv;
-
+#else
+	struct timespec ts;
+#endif 
 	vec[0].iov_base = buf;
 	vec[0].iov_len = PACKET_SIZE;
 
@@ -607,6 +640,7 @@ netRecvGeneral(Octet * buf, TimeInternal * time, NetPath * netPath)
 
 		return 0;
 	}
+#if defined(linux)
 	tv = 0;
 	for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL; 
 	     cmsg = CMSG_NXTHDR(&msg, cmsg)) {
@@ -620,6 +654,21 @@ netRecvGeneral(Octet * buf, TimeInternal * time, NetPath * netPath)
 		time->nanoseconds = tv->tv_usec * 1000;
 		DBGV("kernel recv time stamp %us %dns\n", 
 		     time->seconds, time->nanoseconds);
+#else /* FreeBSD has more accurate time stamps */
+	bzero(&ts, sizeof(ts));
+	for (cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL; 
+	     cmsg = CMSG_NXTHDR(&msg, cmsg)) {
+		if (cmsg->cmsg_level == SOL_SOCKET && 
+		    cmsg->cmsg_type == SCM_BINTIME)
+			bintime2timespec((struct bintime *)CMSG_DATA(cmsg),
+					 &ts);
+	}
+
+	if (ts.tv_sec != 0) {
+		time->seconds = ts.tv_sec;
+		time->nanoseconds = ts.tv_nsec;
+		DBGV("kernel recv time stamp %us %dns\n", time->seconds, time->nanoseconds);
+#endif /* Linux or FreeBSD */
 	} else {
 		/*
 		 * do not try to get by with recording the time here, better