From: millert <millert@openbsd.org>
Date: Fri, 1 Jul 2016 15:47:15 +0000 (+0000)
Subject: Avoid printing f->f_lasttime and/or f->f_prevhost if they are empty.
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=13a8eb257b4c0056959924e16a3d8f45ccdffac2;p=openbsd

Avoid printing f->f_lasttime and/or f->f_prevhost if they are empty.
This fixes a long-standing issue where syslogd would print 15 NUL
bytes followed by two blank spaces before the log message for
warnings generated while parsing syslog.conf.  OK bluhm@
---

diff --git a/usr.sbin/syslogd/syslogd.c b/usr.sbin/syslogd/syslogd.c
index e916ef12e1c..a3f83d614d3 100644
--- a/usr.sbin/syslogd/syslogd.c
+++ b/usr.sbin/syslogd/syslogd.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: syslogd.c,v 1.206 2016/07/01 15:00:48 millert Exp $	*/
+/*	$OpenBSD: syslogd.c,v 1.207 2016/07/01 15:47:15 millert Exp $	*/
 
 /*
  * Copyright (c) 1983, 1988, 1993, 1994
@@ -1738,20 +1738,36 @@ fprintlog(struct filed *f, int flags, char *msg)
 		v->iov_base = "";
 		v->iov_len = 0;
 		v++;
-	} else {
+	} else if (f->f_lasttime[0] != '\0') {
 		v->iov_base = f->f_lasttime;
 		v->iov_len = 15;
 		v++;
 		v->iov_base = " ";
 		v->iov_len = 1;
 		v++;
+	} else {
+		v->iov_base = "";
+		v->iov_len = 0;
+		v++;
+		v->iov_base = "";
+		v->iov_len = 0;
+		v++;
+	}
+	if (f->f_prevhost[0] != '\0') {
+		v->iov_base = f->f_prevhost;
+		v->iov_len = strlen(v->iov_base);
+		v++;
+		v->iov_base = " ";
+		v->iov_len = 1;
+		v++;
+	} else {
+		v->iov_base = "";
+		v->iov_len = 0;
+		v++;
+		v->iov_base = "";
+		v->iov_len = 0;
+		v++;
 	}
-	v->iov_base = f->f_prevhost;
-	v->iov_len = strlen(v->iov_base);
-	v++;
-	v->iov_base = " ";
-	v->iov_len = 1;
-	v++;
 
 	if (msg) {
 		v->iov_base = msg;