1 files changed, 33 insertions, 0 deletions
diff --git a/format/commitgraph/read/layer_close.go b/format/commitgraph/read/layer_close.go
new file mode 100644
index 00000000..03dc91d5
--- /dev/null
+++ b/format/commitgraph/read/layer_close.go
@@ -0,0 +1,33 @@
+package read
+
+import "syscall"
+
+func closeLayers(layers []layer) {
+	for i := len(layers) - 1; i >= 0; i-- {
+		_ = layers[i].close()
+	}
+}
+
+func (layer *layer) close() error {
+	var closeErr error
+
+	if layer.data != nil {
+		err := syscall.Munmap(layer.data)
+		if err != nil {
+			closeErr = err
+		}
+
+		layer.data = nil
+	}
+
+	if layer.file != nil {
+		err := layer.file.Close()
+		if err != nil && closeErr == nil {
+			closeErr = err
+		}
+
+		layer.file = nil
+	}
+
+	return closeErr
+}