summaryrefslogtreecommitdiffstats
path: root/lib/isc/ht.c
diff options
context:
space:
mode:
authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 07:24:22 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 07:24:22 +0000
commit45d6379135504814ab723b57f0eb8be23393a51d (patch)
treed4f2ec4acca824a8446387a758b0ce4238a4dffa /lib/isc/ht.c
parentInitial commit. (diff)
downloadbind9-45d6379135504814ab723b57f0eb8be23393a51d.tar.xz
bind9-45d6379135504814ab723b57f0eb8be23393a51d.zip
Adding upstream version 1:9.16.44.upstream/1%9.16.44upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/isc/ht.c')
-rw-r--r--lib/isc/ht.c342
1 files changed, 342 insertions, 0 deletions
diff --git a/lib/isc/ht.c b/lib/isc/ht.c
new file mode 100644
index 0000000..07a36b4
--- /dev/null
+++ b/lib/isc/ht.c
@@ -0,0 +1,342 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, you can obtain one at https://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+#include <inttypes.h>
+#include <string.h>
+
+#include <isc/hash.h>
+#include <isc/ht.h>
+#include <isc/magic.h>
+#include <isc/mem.h>
+#include <isc/result.h>
+#include <isc/types.h>
+#include <isc/util.h>
+
+typedef struct isc_ht_node isc_ht_node_t;
+
+#define ISC_HT_MAGIC ISC_MAGIC('H', 'T', 'a', 'b')
+#define ISC_HT_VALID(ht) ISC_MAGIC_VALID(ht, ISC_HT_MAGIC)
+
+struct isc_ht_node {
+ void *value;
+ isc_ht_node_t *next;
+ size_t keysize;
+ unsigned char key[FLEXIBLE_ARRAY_MEMBER];
+};
+
+struct isc_ht {
+ unsigned int magic;
+ isc_mem_t *mctx;
+ size_t size;
+ size_t mask;
+ unsigned int count;
+ isc_ht_node_t **table;
+};
+
+struct isc_ht_iter {
+ isc_ht_t *ht;
+ size_t i;
+ isc_ht_node_t *cur;
+};
+
+void
+isc_ht_init(isc_ht_t **htp, isc_mem_t *mctx, uint8_t bits) {
+ isc_ht_t *ht = NULL;
+ size_t i;
+
+ REQUIRE(htp != NULL && *htp == NULL);
+ REQUIRE(mctx != NULL);
+ REQUIRE(bits >= 1 && bits <= (sizeof(size_t) * 8 - 1));
+
+ ht = isc_mem_get(mctx, sizeof(struct isc_ht));
+
+ ht->mctx = NULL;
+ isc_mem_attach(mctx, &ht->mctx);
+
+ ht->size = ((size_t)1 << bits);
+ ht->mask = ((size_t)1 << bits) - 1;
+ ht->count = 0;
+
+ ht->table = isc_mem_get(ht->mctx, ht->size * sizeof(isc_ht_node_t *));
+
+ for (i = 0; i < ht->size; i++) {
+ ht->table[i] = NULL;
+ }
+
+ ht->magic = ISC_HT_MAGIC;
+
+ *htp = ht;
+}
+
+void
+isc_ht_destroy(isc_ht_t **htp) {
+ isc_ht_t *ht;
+ size_t i;
+
+ REQUIRE(htp != NULL);
+
+ ht = *htp;
+ *htp = NULL;
+
+ REQUIRE(ISC_HT_VALID(ht));
+
+ ht->magic = 0;
+
+ for (i = 0; i < ht->size; i++) {
+ isc_ht_node_t *node = ht->table[i];
+ while (node != NULL) {
+ isc_ht_node_t *next = node->next;
+ ht->count--;
+ isc_mem_put(ht->mctx, node,
+ offsetof(isc_ht_node_t, key) +
+ node->keysize);
+ node = next;
+ }
+ }
+
+ INSIST(ht->count == 0);
+
+ isc_mem_put(ht->mctx, ht->table, ht->size * sizeof(isc_ht_node_t *));
+ isc_mem_putanddetach(&ht->mctx, ht, sizeof(struct isc_ht));
+}
+
+isc_result_t
+isc_ht_add(isc_ht_t *ht, const unsigned char *key, uint32_t keysize,
+ void *value) {
+ isc_ht_node_t *node;
+ uint32_t hash;
+
+ REQUIRE(ISC_HT_VALID(ht));
+ REQUIRE(key != NULL && keysize > 0);
+
+ hash = isc_hash_function(key, keysize, true);
+ node = ht->table[hash & ht->mask];
+ while (node != NULL) {
+ if (keysize == node->keysize &&
+ memcmp(key, node->key, keysize) == 0)
+ {
+ return (ISC_R_EXISTS);
+ }
+ node = node->next;
+ }
+
+ node = isc_mem_get(ht->mctx, offsetof(isc_ht_node_t, key) + keysize);
+
+ memmove(node->key, key, keysize);
+ node->keysize = keysize;
+ node->next = ht->table[hash & ht->mask];
+ node->value = value;
+
+ ht->count++;
+ ht->table[hash & ht->mask] = node;
+ return (ISC_R_SUCCESS);
+}
+
+isc_result_t
+isc_ht_find(const isc_ht_t *ht, const unsigned char *key, uint32_t keysize,
+ void **valuep) {
+ isc_ht_node_t *node;
+ uint32_t hash;
+
+ REQUIRE(ISC_HT_VALID(ht));
+ REQUIRE(key != NULL && keysize > 0);
+ REQUIRE(valuep == NULL || *valuep == NULL);
+
+ hash = isc_hash_function(key, keysize, true);
+ node = ht->table[hash & ht->mask];
+ while (node != NULL) {
+ if (keysize == node->keysize &&
+ memcmp(key, node->key, keysize) == 0)
+ {
+ if (valuep != NULL) {
+ *valuep = node->value;
+ }
+ return (ISC_R_SUCCESS);
+ }
+ node = node->next;
+ }
+
+ return (ISC_R_NOTFOUND);
+}
+
+isc_result_t
+isc_ht_delete(isc_ht_t *ht, const unsigned char *key, uint32_t keysize) {
+ isc_ht_node_t *node, *prev;
+ uint32_t hash;
+
+ REQUIRE(ISC_HT_VALID(ht));
+ REQUIRE(key != NULL && keysize > 0);
+
+ prev = NULL;
+ hash = isc_hash_function(key, keysize, true);
+ node = ht->table[hash & ht->mask];
+ while (node != NULL) {
+ if (keysize == node->keysize &&
+ memcmp(key, node->key, keysize) == 0)
+ {
+ if (prev == NULL) {
+ ht->table[hash & ht->mask] = node->next;
+ } else {
+ prev->next = node->next;
+ }
+ isc_mem_put(ht->mctx, node,
+ offsetof(isc_ht_node_t, key) +
+ node->keysize);
+ ht->count--;
+
+ return (ISC_R_SUCCESS);
+ }
+
+ prev = node;
+ node = node->next;
+ }
+ return (ISC_R_NOTFOUND);
+}
+
+void
+isc_ht_iter_create(isc_ht_t *ht, isc_ht_iter_t **itp) {
+ isc_ht_iter_t *it;
+
+ REQUIRE(ISC_HT_VALID(ht));
+ REQUIRE(itp != NULL && *itp == NULL);
+
+ it = isc_mem_get(ht->mctx, sizeof(isc_ht_iter_t));
+
+ it->ht = ht;
+ it->i = 0;
+ it->cur = NULL;
+
+ *itp = it;
+}
+
+void
+isc_ht_iter_destroy(isc_ht_iter_t **itp) {
+ isc_ht_iter_t *it;
+ isc_ht_t *ht;
+
+ REQUIRE(itp != NULL && *itp != NULL);
+
+ it = *itp;
+ *itp = NULL;
+ ht = it->ht;
+ isc_mem_put(ht->mctx, it, sizeof(isc_ht_iter_t));
+}
+
+isc_result_t
+isc_ht_iter_first(isc_ht_iter_t *it) {
+ REQUIRE(it != NULL);
+
+ it->i = 0;
+ while (it->i < it->ht->size && it->ht->table[it->i] == NULL) {
+ it->i++;
+ }
+
+ if (it->i == it->ht->size) {
+ return (ISC_R_NOMORE);
+ }
+
+ it->cur = it->ht->table[it->i];
+
+ return (ISC_R_SUCCESS);
+}
+
+isc_result_t
+isc_ht_iter_next(isc_ht_iter_t *it) {
+ REQUIRE(it != NULL);
+ REQUIRE(it->cur != NULL);
+
+ it->cur = it->cur->next;
+ if (it->cur == NULL) {
+ do {
+ it->i++;
+ } while (it->i < it->ht->size && it->ht->table[it->i] == NULL);
+ if (it->i >= it->ht->size) {
+ return (ISC_R_NOMORE);
+ }
+ it->cur = it->ht->table[it->i];
+ }
+
+ return (ISC_R_SUCCESS);
+}
+
+isc_result_t
+isc_ht_iter_delcurrent_next(isc_ht_iter_t *it) {
+ isc_result_t result = ISC_R_SUCCESS;
+ isc_ht_node_t *to_delete = NULL;
+ isc_ht_node_t *prev = NULL;
+ isc_ht_node_t *node = NULL;
+ uint32_t hash;
+ isc_ht_t *ht;
+ REQUIRE(it != NULL);
+ REQUIRE(it->cur != NULL);
+ to_delete = it->cur;
+ ht = it->ht;
+
+ it->cur = it->cur->next;
+ if (it->cur == NULL) {
+ do {
+ it->i++;
+ } while (it->i < ht->size && ht->table[it->i] == NULL);
+ if (it->i >= ht->size) {
+ result = ISC_R_NOMORE;
+ } else {
+ it->cur = ht->table[it->i];
+ }
+ }
+
+ hash = isc_hash_function(to_delete->key, to_delete->keysize, true);
+ node = ht->table[hash & ht->mask];
+ while (node != to_delete) {
+ prev = node;
+ node = node->next;
+ INSIST(node != NULL);
+ }
+
+ if (prev == NULL) {
+ ht->table[hash & ht->mask] = node->next;
+ } else {
+ prev->next = node->next;
+ }
+ isc_mem_put(ht->mctx, node,
+ offsetof(isc_ht_node_t, key) + node->keysize);
+ ht->count--;
+
+ return (result);
+}
+
+void
+isc_ht_iter_current(isc_ht_iter_t *it, void **valuep) {
+ REQUIRE(it != NULL);
+ REQUIRE(it->cur != NULL);
+ REQUIRE(valuep != NULL && *valuep == NULL);
+
+ *valuep = it->cur->value;
+}
+
+void
+isc_ht_iter_currentkey(isc_ht_iter_t *it, unsigned char **key,
+ size_t *keysize) {
+ REQUIRE(it != NULL);
+ REQUIRE(it->cur != NULL);
+ REQUIRE(key != NULL && *key == NULL);
+
+ *key = it->cur->key;
+ *keysize = it->cur->keysize;
+}
+
+unsigned int
+isc_ht_count(isc_ht_t *ht) {
+ REQUIRE(ISC_HT_VALID(ht));
+
+ return (ht->count);
+}