apk-tools/src/hash.c

113 lines
2.6 KiB
C

/* hash.c - Alpine Package Keeper (APK)
*
* Copyright (C) 2005-2008 Natanael Copa <n@tanael.org>
* Copyright (C) 2008-2011 Timo Teräs <timo.teras@iki.fi>
* All rights reserved.
*
* SPDX-License-Identifier: GPL-2.0-only
*/
#include "apk_defines.h"
#include "apk_hash.h"
void apk_hash_init(struct apk_hash *h, const struct apk_hash_ops *ops,
int num_buckets)
{
h->ops = ops;
apk_hash_array_init(&h->buckets);
apk_hash_array_resize(&h->buckets, num_buckets);
h->num_items = 0;
}
void apk_hash_free(struct apk_hash *h)
{
apk_hash_foreach(h, (apk_hash_enumerator_f) h->ops->delete_item, NULL);
apk_hash_array_free(&h->buckets);
}
int apk_hash_foreach(struct apk_hash *h, apk_hash_enumerator_f e, void *ctx)
{
struct hlist_head *bucket;
apk_hash_node *pos, *n;
ptrdiff_t offset = h->ops->node_offset;
int r;
foreach_array_item(bucket, h->buckets) {
hlist_for_each_safe(pos, n, bucket) {
r = e(((void *) pos) - offset, ctx);
if (r != 0 && ctx != NULL)
return r;
}
}
return 0;
}
apk_hash_item apk_hash_get_hashed(struct apk_hash *h, apk_blob_t key, unsigned long hash)
{
ptrdiff_t offset = h->ops->node_offset;
apk_hash_node *pos;
apk_hash_item item;
apk_blob_t itemkey;
hash %= h->buckets->num;
if (h->ops->compare_item != NULL) {
hlist_for_each(pos, &h->buckets->item[hash]) {
item = ((void *) pos) - offset;
if (h->ops->compare_item(item, key) == 0)
return item;
}
} else {
hlist_for_each(pos, &h->buckets->item[hash]) {
item = ((void *) pos) - offset;
itemkey = h->ops->get_key(item);
if (h->ops->compare(key, itemkey) == 0)
return item;
}
}
return NULL;
}
void apk_hash_insert_hashed(struct apk_hash *h, apk_hash_item item, unsigned long hash)
{
apk_hash_node *node;
hash %= h->buckets->num;
node = (apk_hash_node *) (item + h->ops->node_offset);
hlist_add_head(node, &h->buckets->item[hash]);
h->num_items++;
}
void apk_hash_delete_hashed(struct apk_hash *h, apk_blob_t key, unsigned long hash)
{
ptrdiff_t offset = h->ops->node_offset;
apk_hash_node *pos;
apk_hash_item item;
apk_blob_t itemkey;
hash %= h->buckets->num;
if (h->ops->compare_item != NULL) {
hlist_for_each(pos, &h->buckets->item[hash]) {
item = ((void *) pos) - offset;
if (h->ops->compare_item(item, key) == 0) {
hlist_del(pos, &h->buckets->item[hash]);
h->ops->delete_item(item);
h->num_items--;
break;
}
}
} else {
hlist_for_each(pos, &h->buckets->item[hash]) {
item = ((void *) pos) - offset;
itemkey = h->ops->get_key(item);
if (h->ops->compare(key, itemkey) == 0) {
hlist_del(pos, &h->buckets->item[hash]);
h->ops->delete_item(item);
h->num_items--;
break;
}
}
}
}