Modified clientconfig to match ndots0 (#590)

* Modified clientconfig to match ndots0

* Added Tests for reading resolv.conf

* Cleaned up and removed duplicated code in test

* Added test for ndots below 0

* Cleaned up test

* Clean up

clientconfig.go

@@ -79,8 +79,10 @@ func ClientConfigFromReader(resolvconf io.Reader) (*ClientConfig, error) {
 				switch {
 				case len(s) >= 6 && s[:6] == "ndots:":
 					n, _ := strconv.Atoi(s[6:])
-					if n < 1 {
-						n = 1
+					if n < 0 {
+						n = 0
+					} else if n > 15 {
+						n = 15
 					}
 					c.Ndots = n
 				case len(s) >= 8 && s[:8] == "timeout:":

clientconfig_test.go

@@ -40,6 +40,28 @@ func testConfig(t *testing.T, data string) {
 func TestNameserver(t *testing.T)          { testConfig(t, normal) }
 func TestMissingFinalNewLine(t *testing.T) { testConfig(t, missingNewline) }
 
+func TestNdots(t *testing.T) {
+	ndotsVariants := map[string]int{
+		"options ndots:0":  0,
+		"options ndots:1":  1,
+		"options ndots:15": 15,
+		"options ndots:16": 15,
+		"options ndots:-1": 0,
+		"":                 1,
+	}
+
+	for data := range ndotsVariants {
+		cc, err := ClientConfigFromReader(strings.NewReader(data))
+		if err != nil {
+			t.Errorf("error parsing resolv.conf: %v", err)
+		}
+		if cc.Ndots != ndotsVariants[data] {
+			t.Errorf("Ndots not properly parsed: (Expected: %d / Was: %d)", ndotsVariants[data], cc.Ndots)
+		}
+	}
+
+}
+
 func TestReadFromFile(t *testing.T) {
 	tempDir, err := ioutil.TempDir("", "")
 	if err != nil {
@@ -67,7 +89,7 @@ func TestReadFromFile(t *testing.T) {
 	}
 }
 
-func TestNameList(t *testing.T) {
+func TestNameListNdots1(t *testing.T) {
 	cfg := ClientConfig{
 		Ndots: 1,
 	}
@@ -91,10 +113,18 @@ func TestNameList(t *testing.T) {
 	} else if names[1] != "miek.nl.test." {
 		t.Errorf("NameList didn't return search last: %v", names[1])
 	}
+}
+func TestNameListNdots2(t *testing.T) {
+	cfg := ClientConfig{
+		Ndots: 2,
+	}
 
-	cfg.Ndots = 2
 	// Sent domain has less than NDots and search
-	names = cfg.NameList("miek.nl")
+	cfg.Search = []string{
+		"test",
+	}
+	names := cfg.NameList("miek.nl")
+
 	if len(names) != 2 {
 		t.Errorf("NameList returned != 2 names: %v", names)
 	} else if names[0] != "miek.nl.test." {
@@ -103,3 +133,21 @@ func TestNameList(t *testing.T) {
 		t.Errorf("NameList didn't return sent domain last: %v", names[1])
 	}
 }
+
+func TestNameListNdots0(t *testing.T) {
+	cfg := ClientConfig{
+		Ndots: 0,
+	}
+	cfg.Search = []string{
+		"test",
+	}
+	// Sent domain has less than NDots and search
+	names := cfg.NameList("miek")
+	if len(names) != 2 {
+		t.Errorf("NameList returned != 2 names: %v", names)
+	} else if names[0] != "miek." {
+		t.Errorf("NameList didn't return search first: %v", names[0])
+	} else if names[1] != "miek.test." {
+		t.Errorf("NameList didn't return sent domain last: %v", names[1])
+	}
+}