src/lib/libfuse/tree.c

104 lines
2.2 KiB
C

/* $OpenBSD: tree.c,v 1.2 2014/02/05 20:13:58 syl Exp $ */
/*
* Copyright (c) 2012 Eric Faurot <eric@openbsd.org>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <stdlib.h>
#include <errno.h>
#include "fuse_private.h"
struct treeentry {
SPLAY_ENTRY(treeentry) entry;
uint64_t id;
void *data;
};
static int treeentry_cmp(struct treeentry *, struct treeentry *);
SPLAY_PROTOTYPE(tree, treeentry, entry, treeentry_cmp);
int
tree_check(struct tree *t, uint64_t id)
{
struct treeentry key;
key.id = id;
return (SPLAY_FIND(tree, t, &key) != NULL);
}
void *
tree_set(struct tree *t, uint64_t id, void *data)
{
struct treeentry *entry, key;
key.id = id;
if ((entry = SPLAY_FIND(tree, t, &key)) == NULL) {
entry = malloc(sizeof *entry);
if (entry == NULL)
return (NULL);
entry->id = id;
SPLAY_INSERT(tree, t, entry);
}
entry->data = data;
return (entry);
}
void *
tree_get(struct tree *t, uint64_t id)
{
struct treeentry key, *entry;
key.id = id;
if ((entry = SPLAY_FIND(tree, t, &key)) == NULL) {
errno = ENOENT;
return (NULL);
}
return (entry->data);
}
void *
tree_pop(struct tree *t, uint64_t id)
{
struct treeentry key, *entry;
void *data;
key.id = id;
if ((entry = SPLAY_FIND(tree, t, &key)) == NULL)
return (NULL);
data = entry->data;
SPLAY_REMOVE(tree, t, entry);
free(entry);
return (data);
}
static int
treeentry_cmp(struct treeentry *a, struct treeentry *b)
{
if (a->id < b->id)
return (-1);
if (a->id > b->id)
return (1);
return (0);
}
SPLAY_GENERATE(tree, treeentry, entry, treeentry_cmp);