git/reftable/tree.h

46 lines
1.3 KiB
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;
};
/*
* Search the tree for the node matching the given key using `compare` as
* comparison function. Returns the node whose key matches or `NULL` in case
* the key does not exist in the tree.
*/
struct tree_node *tree_search(struct tree_node *tree,
void *key,
int (*compare)(const void *, const void *));
/*
* Insert a node into the tree. Returns the newly inserted node if the key does
* not yet exist. Otherwise it returns the preexisting node. Returns `NULL`
* when allocating the new node fails.
*/
struct tree_node *tree_insert(struct tree_node **rootp,
void *key,
int (*compare)(const void *, const void *));
/* 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