Fix and preserve file permissions when copying raw files (Fixes #15)

main.go

@@ -545,23 +545,40 @@ func buildHTML(path string, w io.Writer, vars Vars) error {
 
 // Copies file as is from path to writer
 func buildRaw(path string, w io.Writer) error {
-	in, err := os.Open(path)
+	r, err := os.Open(path)
 	if err != nil {
 		return err
 	}
-	defer in.Close()
+	defer r.Close()
+
 	if w == nil {
-		out, err := os.Create(filepath.Join(PUBDIR, path))
+		stat, err := os.Stat(path)
+		if err != nil {
+			return err
+		}
+
+		fn := filepath.Join(PUBDIR, path)
+
+		out, err := os.Create(fn)
 		if err != nil {
 			return err
 		}
 		defer out.Close()
+
+		if err := os.Chmod(fn, stat.Mode()); err != nil {
+			return err
+		}
+
 		w = out
 	}
-	_, err = io.Copy(w, in)
+
+	if _, err := io.Copy(w, r); err != nil {
 		return err
 	}
 
+	return nil
+}
+
 func build(path string, w io.Writer, vars Vars) error {
 	if Ignore.MatchesPath(path) {
 		return nil