Fix etchosts.Update to not target hosts with given hostname as prefix

Signed-off-by: Travis Thieman <travis.thieman@gmail.com>
moby · Oct 9, 2015 · 069c342 · 069c342
1 parent d4989a6
commit 069c342
Show file tree

Hide file tree

Showing 2 changed files with 9 additions and 5 deletions.
diff --git a/etchosts/etchosts.go b/etchosts/etchosts.go
@@ -122,6 +122,6 @@ func Update(path, IP, hostname string) error {
 	if err != nil {
 		return err
 	}
-	var re = regexp.MustCompile(fmt.Sprintf("(\\S*)(\\t%s)", regexp.QuoteMeta(hostname)))
-	return ioutil.WriteFile(path, re.ReplaceAll(old, []byte(IP+"$2")), 0644)
+	var re = regexp.MustCompile(fmt.Sprintf("(\\S*)(\\t%s)(\\s|\\.)", regexp.QuoteMeta(hostname)))
+	return ioutil.WriteFile(path, re.ReplaceAll(old, []byte(IP+"$2"+"$3")), 0644)
 }
diff --git a/etchosts/etchosts_test.go b/etchosts/etchosts_test.go
@@ -152,6 +152,10 @@ func TestUpdateIgnoresPrefixedHostname(t *testing.T) {
 			Hosts: "prefixAndMore",
 			IP:    "3.3.3.3",
 		},
+		Record{
+			Hosts: "unaffectedHost",
+			IP:    "4.4.4.4",
+		},
 	}); err != nil {
 		t.Fatal(err)
 	}
@@ -161,11 +165,11 @@ func TestUpdateIgnoresPrefixedHostname(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	if expected := "2.2.2.2\tprefix\n3.3.3.3\tprefixAndMore\n"; !bytes.Contains(content, []byte(expected)) {
+	if expected := "2.2.2.2\tprefix\n3.3.3.3\tprefixAndMore\n4.4.4.4\tunaffectedHost\n"; !bytes.Contains(content, []byte(expected)) {
 		t.Fatalf("Expected to find '%s' got '%s'", expected, content)
 	}
 
-	if err := Update(file.Name(), "4.4.4.4", "prefix"); err != nil {
+	if err := Update(file.Name(), "5.5.5.5", "prefix"); err != nil {
 		t.Fatal(err)
 	}
 
@@ -174,7 +178,7 @@ func TestUpdateIgnoresPrefixedHostname(t *testing.T) {
 		t.Fatal(err)
 	}
 
-	if expected := "4.4.4.4\tprefix\n3.3.3.3\tprefixAndMore\n"; !bytes.Contains(content, []byte(expected)) {
+	if expected := "5.5.5.5\tprefix\n3.3.3.3\tprefixAndMore\n4.4.4.4\tunaffectedHost\n"; !bytes.Contains(content, []byte(expected)) {
 		t.Fatalf("Expected to find '%s' got '%s'", expected, content)
 	}