1 files changed, 63 insertions, 0 deletions
diff --git a/reftable/tree.c b/reftable/tree.c
new file mode 100644
index 0000000000..82db7995dd
--- /dev/null
+++ b/reftable/tree.c
@@ -0,0 +1,63 @@
+/*
+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
+*/
+
+#include "tree.h"
+
+#include "basics.h"
+#include "system.h"
+
+struct tree_node *tree_search(void *key, struct tree_node **rootp,
+			      int (*compare)(const void *, const void *),
+			      int insert)
+{
+	int res;
+	if (*rootp == NULL) {
+		if (!insert) {
+			return NULL;
+		} else {
+			struct tree_node *n =
+				reftable_calloc(sizeof(struct tree_node));
+			n->key = key;
+			*rootp = n;
+			return *rootp;
+		}
+	}
+
+	res = compare(key, (*rootp)->key);
+	if (res < 0)
+		return tree_search(key, &(*rootp)->left, compare, insert);
+	else if (res > 0)
+		return tree_search(key, &(*rootp)->right, compare, insert);
+	return *rootp;
+}
+
+void infix_walk(struct tree_node *t, void (*action)(void *arg, void *key),
+		void *arg)
+{
+	if (t->left) {
+		infix_walk(t->left, action, arg);
+	}
+	action(arg, t->key);
+	if (t->right) {
+		infix_walk(t->right, action, arg);
+	}
+}
+
+void tree_free(struct tree_node *t)
+{
+	if (t == NULL) {
+		return;
+	}
+	if (t->left) {
+		tree_free(t->left);
+	}
+	if (t->right) {
+		tree_free(t->right);
+	}
+	reftable_free(t);
+}