1 files changed, 40 insertions, 0 deletions
diff --git a/reftable/pq.h b/reftable/pq.h
new file mode 100644
index 0000000000..42310670b0
--- /dev/null
+++ b/reftable/pq.h
@@ -0,0 +1,40 @@
+/*
+ * 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 PQ_H
+#define PQ_H
+
+#include "record.h"
+
+struct pq_entry {
+	size_t index;
+	struct reftable_record *rec;
+};
+
+struct merged_iter_pqueue {
+	struct pq_entry *heap;
+	size_t len;
+	size_t cap;
+};
+
+int merged_iter_pqueue_remove(struct merged_iter_pqueue *pq, struct pq_entry *out);
+int merged_iter_pqueue_add(struct merged_iter_pqueue *pq, const struct pq_entry *e);
+void merged_iter_pqueue_release(struct merged_iter_pqueue *pq);
+int pq_less(struct pq_entry *a, struct pq_entry *b);
+
+static inline struct pq_entry merged_iter_pqueue_top(struct merged_iter_pqueue pq)
+{
+	return pq.heap[0];
+}
+
+static inline int merged_iter_pqueue_is_empty(struct merged_iter_pqueue pq)
+{
+	return pq.len == 0;
+}
+
+#endif