From 09499bd07fe68a1900fa2b5b274ef74f12d42a6c Mon Sep 17 00:00:00 2001
From: Tom Thorogood <me+github@tomthorogood.co.uk>
Date: Fri, 4 Jan 2019 18:43:00 +1030
Subject: [PATCH] Use IsFqdn and Fqdn helper functions more (#892)

---
 defaults.go | 4 +---
 labels.go   | 2 +-
 msg.go      | 2 +-
 scan.go     | 2 +-
 4 files changed, 4 insertions(+), 6 deletions(-)

diff --git a/defaults.go b/defaults.go
index a5dab628..6eb079d2 100644
--- a/defaults.go
+++ b/defaults.go
@@ -176,9 +176,7 @@ func IsDomainName(s string) (labels int, ok bool) {
 		return 0, false
 	}
 
-	if !strings.HasSuffix(s, ".") {
-		s += "."
-	}
+	s = Fqdn(s)
 
 	// Each dot ends a segment of the name. Except for escaped dots (\.), which
 	// are normal dots.
diff --git a/labels.go b/labels.go
index 577fc59d..bc182ba3 100644
--- a/labels.go
+++ b/labels.go
@@ -16,7 +16,7 @@ func SplitDomainName(s string) (labels []string) {
 	fqdnEnd := 0 // offset of the final '.' or the length of the name
 	idx := Split(s)
 	begin := 0
-	if s[len(s)-1] == '.' {
+	if IsFqdn(s) {
 		fqdnEnd = len(s) - 1
 	} else {
 		fqdnEnd = len(s)
diff --git a/msg.go b/msg.go
index 71e9241e..f5be33fc 100644
--- a/msg.go
+++ b/msg.go
@@ -244,7 +244,7 @@ func packDomainName(s string, msg []byte, off int, compression compressionMap, c
 	}
 
 	// If not fully qualified, error out.
-	if s[ls-1] != '.' {
+	if !IsFqdn(s) {
 		return len(msg), ErrFqdn
 	}
 
diff --git a/scan.go b/scan.go
index eaad5813..f067d850 100644
--- a/scan.go
+++ b/scan.go
@@ -1262,7 +1262,7 @@ func toAbsoluteName(name, origin string) (absolute string, ok bool) {
 	}
 
 	// check if name is already absolute
-	if name[len(name)-1] == '.' {
+	if IsFqdn(name) {
 		return name, true
 	}