1 files changed, 199 insertions, 0 deletions
diff --git a/src/hash.c b/src/hash.c
new file mode 100644
index 0000000..274a140
--- /dev/null
+++ b/src/hash.c
@@ -0,0 +1,199 @@
+/*
+ * (C) 2006-2007 by Pablo Neira Ayuso <pablo@netfilter.org>
+ * 
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * Description: generic hash table implementation
+ */
+
+#include <stdio.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <string.h>
+#include "slist.h"
+#include "hash.h"
+
+
+struct hashtable_node *hashtable_alloc_node(int datasize, void *data)
+{
+	struct hashtable_node *n;
+	int size = sizeof(struct hashtable_node) + datasize;
+
+	n = malloc(size);
+	if (!n)
+		return NULL;
+	memset(n, 0, size);
+	memcpy(n->data, data, datasize);
+
+	return n;
+}
+
+void hashtable_destroy_node(struct hashtable_node *h)
+{
+	free(h);
+}
+
+struct hashtable *
+hashtable_create(int hashsize, int limit, int datasize,
+		 u_int32_t (*hash)(const void *data, struct hashtable *table),
+		 int (*compare)(const void *data1, const void *data2))
+{
+	int i;
+	struct hashtable *h;
+	struct hashtype *t;
+	int size = sizeof(struct hashtable)
+		   + hashsize * sizeof(struct slist_head);
+
+	h = (struct hashtable *) malloc(size);
+	if (!h) {
+		errno = ENOMEM;
+		return NULL;
+	}
+
+	memset(h, 0, size);
+	for (i=0; i<hashsize; i++)
+		INIT_SLIST_HEAD(h->members[i]);
+
+	h->hashsize = hashsize;
+	h->limit = limit;
+	h->datasize = datasize;
+	h->hash = hash;
+	h->compare = compare;
+
+	return h;
+}
+
+void hashtable_destroy(struct hashtable *h)
+{
+	hashtable_flush(h);
+	free(h);
+}
+
+void *hashtable_add(struct hashtable *table, void *data)
+{
+	struct slist_head *e;
+	struct hashtable_node *n;
+	u_int32_t id;
+	int i;
+
+	/* hash table is full */
+	if (table->count >= table->limit) {
+		errno = ENOSPC;
+		return NULL;
+	}
+
+	id = table->hash(data, table);
+
+	slist_for_each(e, &table->members[id]) {
+		n = slist_entry(e, struct hashtable_node, head);
+		if (table->compare(n->data, data)) {
+			errno = EEXIST;
+			return NULL;
+		}
+	}
+
+	n = hashtable_alloc_node(table->datasize, data);
+	if (n == NULL) {
+		errno = ENOMEM;
+		return NULL;
+	}
+
+	slist_add(&table->members[id], &n->head);
+	table->count++;
+
+	return n->data;
+}
+
+void *hashtable_test(struct hashtable *table, const void *data)
+{
+	struct slist_head *e;
+	u_int32_t id;
+	struct hashtable_node *n;
+	int i;
+
+	id = table->hash(data, table);
+
+	slist_for_each(e, &table->members[id]) {
+		n = slist_entry(e, struct hashtable_node, head);
+		if (table->compare(n->data, data))
+			return n->data;
+	}
+
+	errno = ENOENT;
+	return NULL;
+}
+
+int hashtable_del(struct hashtable *table, void *data)
+{
+	struct slist_head *e, *next, *prev;
+	u_int32_t id;
+	struct hashtable_node *n;
+	int i;
+
+	id = table->hash(data, table);
+
+	slist_for_each_safe(e, prev, next, &table->members[id]) {
+		n = slist_entry(e, struct hashtable_node, head);
+		if (table->compare(n->data, data)) {
+			slist_del(e, prev);
+			hashtable_destroy_node(n);
+			table->count--;
+			return 0;
+		}
+	}
+	errno = ENOENT;
+	return -1;
+}
+
+int hashtable_flush(struct hashtable *table)
+{
+	int i;
+	struct slist_head *e, *next, *prev;
+	struct hashtable_node *n;
+
+	for (i=0; i < table->hashsize; i++)
+		slist_for_each_safe(e, prev, next, &table->members[i]) {
+			n = slist_entry(e, struct hashtable_node, head);
+			slist_del(e, prev);
+			hashtable_destroy_node(n);
+		}
+
+	table->count = 0;
+	
+	return 0;
+}
+
+int hashtable_iterate(struct hashtable *table, void *data,
+		      int (*iterate)(void *data1, void *data2))
+{
+	int i;
+	struct slist_head *e, *next, *prev;
+	struct hashtable_node *n;
+
+	for (i=0; i < table->hashsize; i++) {
+		slist_for_each_safe(e, prev, next, &table->members[i]) {
+			n = slist_entry(e, struct hashtable_node, head);
+			if (iterate(data, n->data) == -1)
+				return -1;
+		}
+	}
+	return 0;
+}
+
+unsigned int hashtable_counter(struct hashtable *table)
+{
+	return table->count;
+}