1 files changed, 42 insertions, 0 deletions
diff --git a/src/crimson/os/seastore/onode_manager/staged-fltree/node_delta_recorder.h b/src/crimson/os/seastore/onode_manager/staged-fltree/node_delta_recorder.h
new file mode 100644
index 000000000..d08a99015
--- /dev/null
+++ b/src/crimson/os/seastore/onode_manager/staged-fltree/node_delta_recorder.h
@@ -0,0 +1,42 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:nil -*-
+// vim: ts=8 sw=2 smarttab
+
+#pragma once
+
+#include "include/buffer.h"
+#include "node_types.h"
+
+namespace crimson::os::seastore::onode {
+
+/**
+ * DeltaRecorder
+ *
+ * An abstracted class to encapsulate different implementations to apply delta
+ * to a specific node layout.
+ */
+class DeltaRecorder {
+ public:
+  virtual ~DeltaRecorder() {
+    assert(is_empty());
+  }
+
+  bool is_empty() const {
+    return encoded.length() == 0;
+  }
+
+  ceph::bufferlist get_delta() {
+    assert(!is_empty());
+    return std::move(encoded);
+  }
+
+  virtual node_type_t node_type() const = 0;
+  virtual field_type_t field_type() const = 0;
+  virtual void apply_delta(ceph::bufferlist::const_iterator&,
+                           NodeExtentMutable&) = 0;
+
+ protected:
+  DeltaRecorder() = default;
+  ceph::bufferlist encoded;
+};
+
+}