reftable: generic interface to tables

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 39 insertions, 0 deletions

diff --git a/reftable/reftable-iterator.h b/reftable/reftable-iterator.h
new file mode 100644
index 0000000000..d3eee7af35
--- /dev/null
+++ b/reftable/reftable-iterator.h
@@ -0,0 +1,39 @@
+/*
+Copyright 2020 Google LLC
+
+Use of this source code is governed by a BSD-style
+license that can be found in the LICENSE file or at
+https://developers.google.com/open-source/licenses/bsd
+*/
+
+#ifndef REFTABLE_ITERATOR_H
+#define REFTABLE_ITERATOR_H
+
+#include "reftable-record.h"
+
+struct reftable_iterator_vtable;
+
+/* iterator is the generic interface for walking over data stored in a
+ * reftable.
+ */
+struct reftable_iterator {
+	struct reftable_iterator_vtable *ops;
+	void *iter_arg;
+};
+
+/* reads the next reftable_ref_record. Returns < 0 for error, 0 for OK and > 0:
+ * end of iteration.
+ */
+int reftable_iterator_next_ref(struct reftable_iterator *it,
+			       struct reftable_ref_record *ref);
+
+/* reads the next reftable_log_record. Returns < 0 for error, 0 for OK and > 0:
+ * end of iteration.
+ */
+int reftable_iterator_next_log(struct reftable_iterator *it,
+			       struct reftable_log_record *log);
+
+/* releases resources associated with an iterator. */
+void reftable_iterator_destroy(struct reftable_iterator *it);
+
+#endif