Fix/clarify some comments. do memset()'s only when variable is going

to be used.

2 files changed, 11 insertions, 31 deletions

diff --git a/sbin/dhclient/dhclient.c b/sbin/dhclient/dhclient.c
index 16dd15ac8c7..dc0feac7bff 100644
--- a/sbin/dhclient/dhclient.c
+++ b/sbin/dhclient/dhclient.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: dhclient.c,v 1.252 2013/06/09 16:21:50 krw Exp $	*/
+/*	$OpenBSD: dhclient.c,v 1.253 2013/06/09 17:31:54 krw Exp $	*/
 
 /*
  * Copyright 2004 Henning Brauer <henning@openbsd.org>
@@ -2285,8 +2285,6 @@ priv_write_file(struct imsg_write_file *imsg)
  *	or
  *
  * 	route -q $rdomain add default $router
- *
- * depending on the contents of the gateway parameter.
  */
 void
 add_default_route(int rdomain, struct in_addr addr, struct in_addr gateway)
@@ -2299,8 +2297,9 @@ add_default_route(int rdomain, struct in_addr addr, struct in_addr gateway)
 	addrs = RTA_DST | RTA_NETMASK;
 
 	/*
-	 * Set gateway address if and only if non-zero addr supplied. A
-	 * gateway address of 0 implies '-iface'.
+	 * When 'addr' and 'gateway' are identical the desired behaviour is
+	 * to emulate the '-iface' variant of 'route'. This is done by
+	 * claiming there is no gateway address to use.
 	 */
 	if (bcmp(&gateway, &addr, sizeof(addr)) != 0)
 		addrs |= RTA_GATEWAY;
diff --git a/sbin/dhclient/kroute.c b/sbin/dhclient/kroute.c
index 2a3321c5aab..2b40fd26993 100644
--- a/sbin/dhclient/kroute.c
+++ b/sbin/dhclient/kroute.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: kroute.c,v 1.52 2013/06/09 16:21:50 krw Exp $	*/
+/*	$OpenBSD: kroute.c,v 1.53 2013/06/09 17:31:54 krw Exp $	*/
 
 /*
  * Copyright 2012 Kenneth R Westerback <krw@openbsd.org>
@@ -170,18 +170,6 @@ priv_flush_routes(struct imsg_flush_routes *imsg)
 	free(buf);
 }
 
-/*
- * [priv_]add_default_route is the equivalent of
- *
- *	route -q $rdomain -n flush -inet -iface $interface
- *
- * and one of
- *
- *	route -q $rdomain add default -iface $router
- * 	route -q $rdomain add default $router
- *
- * depending on the contents of the gateway parameter.
- */
 void
 add_route(int rdomain, struct in_addr dest, struct in_addr netmask,
     struct in_addr gateway, int addrs)
@@ -229,11 +217,9 @@ priv_add_route(struct imsg_add_route *imsg)
 	iov[iovcnt].iov_base = &rtm;
 	iov[iovcnt++].iov_len = sizeof(rtm);
 	
-	/* Set destination address. */
-
-	memset(&dest, 0, sizeof(dest));
-
 	if (imsg->addrs & RTA_DST) {
+		memset(&dest, 0, sizeof(dest));
+
 		dest.sin_len = sizeof(dest);
 		dest.sin_family = AF_INET;
 		dest.sin_addr.s_addr = imsg->dest.s_addr;
@@ -245,13 +231,9 @@ priv_add_route(struct imsg_add_route *imsg)
 		iov[iovcnt++].iov_len = sizeof(dest);
 	}
 	
-	/*
-	 * Set gateway address if and only if non-zero addr supplied. A
-	 * gateway address of 0 implies '-iface'.
-	 */
-
-	memset(&gateway, 0, sizeof(gateway));
 	if (imsg->addrs & RTA_GATEWAY) {
+		memset(&gateway, 0, sizeof(gateway));
+
 		gateway.sin_len = sizeof(gateway);
 		gateway.sin_family = AF_INET;
 		gateway.sin_addr.s_addr = imsg->gateway.s_addr;
@@ -264,10 +246,9 @@ priv_add_route(struct imsg_add_route *imsg)
 		iov[iovcnt++].iov_len = sizeof(gateway);
 	}
 
-	/* Add netmask. */
-	memset(&mask, 0, sizeof(mask));
-
 	if (imsg->addrs & RTA_NETMASK) {
+		memset(&mask, 0, sizeof(mask));
+
 		mask.sin_len = sizeof(mask);
 		mask.sin_family = AF_INET;
 		mask.sin_addr.s_addr = imsg->netmask.s_addr;