btrfs-progs/common/rbtree-utils.c

87 lines
1.9 KiB
C

/*
* Copyright (C) 2014 Facebook. All rights reserved.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License v2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 021110-1307, USA.
*/
#include <errno.h>
#include <stddef.h>
#include "kernel-lib/rbtree.h"
#include "kernel-lib/rbtree_types.h"
#include "common/rbtree-utils.h"
int rb_insert(struct rb_root *root, struct rb_node *node,
rb_compare_nodes comp)
{
struct rb_node **p = &root->rb_node;
struct rb_node *parent = NULL;
int ret;
while(*p) {
parent = *p;
ret = comp(parent, node);
if (ret < 0)
p = &(*p)->rb_left;
else if (ret > 0)
p = &(*p)->rb_right;
else
return -EEXIST;
}
rb_link_node(node, parent, p);
rb_insert_color(node, root);
return 0;
}
struct rb_node *rb_search(struct rb_root *root, const void *key, rb_compare_keys comp,
struct rb_node **next_ret)
{
struct rb_node *n = root->rb_node;
struct rb_node *parent = NULL;
int ret = 0;
while(n) {
parent = n;
ret = comp(n, key);
if (ret < 0)
n = n->rb_left;
else if (ret > 0)
n = n->rb_right;
else
return n;
}
if (!next_ret)
return NULL;
if (parent && ret > 0)
parent = rb_next(parent);
*next_ret = parent;
return NULL;
}
void rb_free_nodes(struct rb_root *root, rb_free_node free_node)
{
struct rb_node *node;
while ((node = rb_first(root))) {
rb_erase(node, root);
free_node(node);
}
}