From 61ca100b80ae5ef271219fa9468f0cfde9d64fb8 Mon Sep 17 00:00:00 2001
From: Mark Andrews <marka@isc.org>
Date: Thu, 8 Sep 2016 14:25:20 +1000
Subject: [PATCH] 4466.   [bug]           Interface scanning didn't work on a
 Windows system                         without a non local IPv6 addresses.
 [RT #43130]

---
 CHANGES                       | 3 +++
 lib/isc/win32/interfaceiter.c | 8 ++++----
 2 files changed, 7 insertions(+), 4 deletions(-)

diff --git a/CHANGES b/CHANGES
index f382ac35b8..36e2b3c601 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,3 +1,6 @@
+4466.	[bug]		Interface scanning didn't work on a Windows system
+			without a non local IPv6 addresses. [RT #43130]
+
 4465.	[bug]		Don't use "%z" as Windows doesn't support it.
 			[RT #43131]
 
diff --git a/lib/isc/win32/interfaceiter.c b/lib/isc/win32/interfaceiter.c
index c4cba284e7..89c31e3746 100644
--- a/lib/isc/win32/interfaceiter.c
+++ b/lib/isc/win32/interfaceiter.c
@@ -375,7 +375,7 @@ internal_current6(isc_interfaceiter_t *iter) {
 	memset(&iter->current, 0, sizeof(iter->current));
 	iter->current.af = AF_INET6;
 
-	if (iter->pos6 != 0U || !iter->pos6zero) {
+	if (!iter->pos6zero) {
 		if (iter->pos6 == 0U)
 			iter->pos6zero = ISC_TRUE;
 		get_addr(AF_INET6, &iter->current.address,
@@ -466,9 +466,9 @@ internal_next(isc_interfaceiter_t *iter) {
 
 static isc_result_t
 internal_next6(isc_interfaceiter_t *iter) {
-	if (iter->pos6 == 0 && iter->v6loop)
+	if (iter->pos6 == 0U && iter->v6loop)
 		return (ISC_R_NOMORE);
-	if (iter->pos6 != 0)
+	if (iter->pos6 != 0U)
 		iter->pos6--;
 	return (ISC_R_SUCCESS);
 }
@@ -489,7 +489,7 @@ isc_interfaceiter_first(isc_interfaceiter_t *iter) {
 	if (iter->buf6 != NULL) {
 		iter->pos6 = iter->buf6->iAddressCount;
 		iter->v6loop = ISC_FALSE;
-		iter->pos6zero = ISC_FALSE;
+		iter->pos6zero = ISC_TF(iter->pos6 == 0U);
 	}
 	iter->result = ISC_R_SUCCESS;
 	return (isc_interfaceiter_next(iter));