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/*
* Copyright (C) 2001-2004 Sistina Software, Inc. All rights reserved.
* Copyright (C) 2004-2007 Red Hat, Inc. All rights reserved.
*
* This file is part of the device-mapper userspace tools.
*
* This copyrighted material is made available to anyone wishing to use,
* modify, copy, or redistribute it subject to the terms and conditions
* of the GNU Lesser General Public License v.2.1.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "dmlib.h"
#include "ttree.h"
struct node {
unsigned k;
struct node *l, *m, *r;
void *data;
};
struct ttree {
int klen;
struct dm_pool *mem;
struct node *root;
};
__attribute__((nonnull(1)))
static struct node **_lookup_single(struct node **c, unsigned int k)
{
while (*c) {
if (k < (*c)->k)
c = &((*c)->l);
else if (k > (*c)->k)
c = &((*c)->r);
else {
c = &((*c)->m);
break;
}
}
return c;
}
void *ttree_lookup(struct ttree *tt, unsigned *key)
{
struct node **c = &tt->root;
int count = tt->klen;
while (*c && count) {
c = _lookup_single(c, *key++);
count--;
}
return *c ? (*c)->data : NULL;
}
static struct node *_tree_node(struct dm_pool *mem, unsigned int k)
{
struct node *n = dm_pool_zalloc(mem, sizeof(*n));
if (n)
n->k = k;
return n;
}
int ttree_insert(struct ttree *tt, unsigned int *key, void *data)
{
struct node **c = &tt->root;
int count = tt->klen;
unsigned int k;
do {
k = *key++;
c = _lookup_single(c, k);
count--;
} while (*c && count);
if (!*c) {
count++;
while (count--) {
if (!(*c = _tree_node(tt->mem, k)))
return_0;
if (count) {
k = *key++;
c = &((*c)->m);
}
}
}
(*c)->data = data;
return 1;
}
struct ttree *ttree_create(struct dm_pool *mem, unsigned int klen)
{
struct ttree *tt;
if (!(tt = dm_pool_zalloc(mem, sizeof(*tt))))
return_NULL;
tt->klen = klen;
tt->mem = mem;
return tt;
}
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