1 files changed, 119 insertions, 0 deletions
diff --git a/src/crimson/os/seastore/onode_manager/staged-fltree/tree.h b/src/crimson/os/seastore/onode_manager/staged-fltree/tree.h
new file mode 100644
index 000000000..7ee618cb3
--- /dev/null
+++ b/src/crimson/os/seastore/onode_manager/staged-fltree/tree.h
@@ -0,0 +1,119 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:nil -*-
+// vim: ts=8 sw=2 smarttab
+
+#pragma once
+
+#include <ostream>
+
+#include "common/hobject.h"
+#include "crimson/common/type_helpers.h"
+
+#include "fwd.h"
+#include "tree_types.h"
+
+/**
+ * tree.h
+ *
+ * An example implementation to expose tree interfaces to users. The current
+ * interface design is based on:
+ * - ceph::os::Transaction::create/touch/remove()
+ * - ceph::ObjectStore::collection_list()
+ * - ceph::BlueStore::get_onode()
+ * - db->get_iterator(PREFIIX_OBJ) by ceph::BlueStore::fsck()
+ *
+ * TODO: Redesign the interfaces based on real onode manager requirements.
+ */
+
+namespace crimson::os::seastore::onode {
+
+class Node;
+class Btree {
+ public:
+  using btree_ertr = crimson::errorator<
+    crimson::ct_error::input_output_error,
+    crimson::ct_error::invarg,
+    crimson::ct_error::enoent,
+    crimson::ct_error::erange>;
+  template <class ValueT=void>
+  using btree_future = btree_ertr::future<ValueT>;
+
+  Btree(NodeExtentManagerURef&& nm);
+  Btree(const Btree&) = delete;
+  Btree(Btree&&) = delete;
+  Btree& operator=(const Btree&) = delete;
+  Btree& operator=(Btree&&) = delete;
+  ~Btree();
+
+  btree_future<> mkfs(Transaction&);
+
+  class Cursor;
+  // lookup
+  btree_future<Cursor> begin(Transaction&);
+  btree_future<Cursor> last(Transaction&);
+  Cursor end();
+  btree_future<bool> contains(Transaction&, const ghobject_t&);
+  btree_future<Cursor> find(Transaction&, const ghobject_t&);
+  btree_future<Cursor> lower_bound(Transaction&, const ghobject_t&);
+
+  // modifiers
+  // TODO: replace onode_t
+  btree_future<std::pair<Cursor, bool>>
+  insert(Transaction&, const ghobject_t&, const onode_t&);
+  btree_future<size_t> erase(Transaction&, const ghobject_t& key);
+  btree_future<Cursor> erase(Cursor& pos);
+  btree_future<Cursor> erase(Cursor& first, Cursor& last);
+
+  // stats
+  btree_future<size_t> height(Transaction&);
+  btree_future<tree_stats_t> get_stats_slow(Transaction&);
+  std::ostream& dump(Transaction&, std::ostream&);
+  std::ostream& print(std::ostream& os) const;
+
+  // test_only
+  bool test_is_clean() const;
+  btree_future<> test_clone_from(Transaction& t, Transaction& t_from, Btree& from);
+
+ private:
+  context_t get_context(Transaction& t) { return {*nm, t}; }
+  btree_future<Ref<Node>> get_root(Transaction& t);
+
+  NodeExtentManagerURef nm;
+  RootNodeTrackerURef root_tracker;
+
+  friend class DummyChildPool;
+};
+inline std::ostream& operator<<(std::ostream& os, const Btree& tree) {
+  return tree.print(os);
+}
+
+class tree_cursor_t;
+class Btree::Cursor {
+ public:
+  Cursor(const Cursor&);
+  Cursor(Cursor&&) noexcept;
+  Cursor& operator=(const Cursor&);
+  Cursor& operator=(Cursor&&);
+  ~Cursor();
+
+  bool is_end() const;
+  // XXX: return key_view_t to avoid unecessary ghobject_t constructions
+  ghobject_t get_ghobj() const;
+  const onode_t* value() const;
+  bool operator==(const Cursor& x) const;
+  bool operator!=(const Cursor& x) const { return !(*this == x); }
+  Cursor& operator++();
+  Cursor operator++(int);
+
+ private:
+  Cursor(Btree*, Ref<tree_cursor_t>);
+  Cursor(Btree*);
+
+  static Cursor make_end(Btree*);
+
+  Btree* p_tree;
+  Ref<tree_cursor_t> p_cursor;
+
+  friend class Btree;
+};
+
+}