git/reftable/tree.h
Han-Wen Nienhuys 35425d1034 reftable: a generic binary tree implementation
The reftable format includes support for an (OID => ref) map. This map can speed
up visibility and reachability checks. In particular, various operations along
the fetch/push path within Gerrit have ben sped up by using this structure.

The map is constructed with help of a binary tree. Object IDs are hashes, so
they are uniformly distributed. Hence, the tree does not attempt forced
rebalancing.

Signed-off-by: Han-Wen Nienhuys <hanwen@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-10-08 10:45:48 -07:00

35 lines
924 B
C

/*
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 TREE_H
#define TREE_H
/* tree_node is a generic binary search tree. */
struct tree_node {
void *key;
struct tree_node *left, *right;
};
/* looks for `key` in `rootp` using `compare` as comparison function. If insert
* is set, insert the key if it's not found. Else, return NULL.
*/
struct tree_node *tree_search(void *key, struct tree_node **rootp,
int (*compare)(const void *, const void *),
int insert);
/* performs an infix walk of the tree. */
void infix_walk(struct tree_node *t, void (*action)(void *arg, void *key),
void *arg);
/*
* deallocates the tree nodes recursively. Keys should be deallocated separately
* by walking over the tree. */
void tree_free(struct tree_node *t);
#endif