1 files changed, 143 insertions, 0 deletions
diff --git a/src/hash.c b/src/hash.c
new file mode 100644
index 0000000..fe6a047
--- /dev/null
+++ b/src/hash.c
@@ -0,0 +1,143 @@
+/*
+ * (C) 2006-2009 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 "hash.h"
+
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+#include <limits.h>
+
+struct hashtable *
+hashtable_create(int hashsize, int limit,
+		 uint32_t (*hash)(const void *data,
+		 		  const struct hashtable *table),
+		 int (*compare)(const void *data1, const void *data2))
+{
+	int i;
+	struct hashtable *h;
+	int size = sizeof(struct hashtable)
+		   + hashsize * sizeof(struct list_head);
+
+	h = (struct hashtable *) calloc(size, 1);
+	if (h == NULL) {
+		errno = ENOMEM;
+		return NULL;
+	}
+
+	for (i=0; i<hashsize; i++)
+		INIT_LIST_HEAD(&h->members[i]);
+
+	h->hashsize = hashsize;
+	h->limit = limit;
+	h->hash = hash;
+	h->compare = compare;
+
+	return h;
+}
+
+void hashtable_destroy(struct hashtable *h)
+{
+	free(h);
+}
+
+int hashtable_hash(const struct hashtable *table, const void *data)
+{
+	return table->hash(data, table);
+}
+
+struct hashtable_node *
+hashtable_find(const struct hashtable *table, const void *data, int id)
+{
+	struct list_head *e;
+	struct hashtable_node *n;
+
+	list_for_each(e, &table->members[id]) {
+		n = list_entry(e, struct hashtable_node, head);
+		if (table->compare(n, data)) {
+			return n;
+		}
+	}
+	errno = ENOENT;
+	return NULL;
+}
+
+int hashtable_add(struct hashtable *table, struct hashtable_node *n, int id)
+{
+	/* hash table is full */
+	if (table->count >= table->limit) {
+		errno = ENOSPC;
+		return -1;
+	}
+	list_add(&n->head, &table->members[id]);
+	table->count++;
+	return 0;
+}
+
+void hashtable_del(struct hashtable *table, struct hashtable_node *n)
+{
+	list_del(&n->head);
+	table->count--;
+}
+
+int hashtable_flush(struct hashtable *table)
+{
+	uint32_t i;
+	struct list_head *e, *tmp;
+	struct hashtable_node *n;
+
+	for (i=0; i < table->hashsize; i++) {
+		list_for_each_safe(e, tmp, &table->members[i]) {
+			n = list_entry(e, struct hashtable_node, head);
+			free(n);
+		}
+	}
+	return 0;
+}
+
+int
+hashtable_iterate_limit(struct hashtable *table, void *data,
+			uint32_t from, uint32_t steps,
+		        int (*iterate)(void *data1, void *n))
+{
+	uint32_t i;
+	struct list_head *e, *tmp;
+	struct hashtable_node *n;
+
+	for (i=from; i < table->hashsize && i < from+steps; i++) {
+		list_for_each_safe(e, tmp, &table->members[i]) {
+			n = list_entry(e, struct hashtable_node, head);
+			if (iterate(data, n) == -1)
+				return -1;
+		}
+	}
+	return i;
+}
+
+int hashtable_iterate(struct hashtable *table, void *data,
+		      int (*iterate)(void *data1, void *n))
+{
+	return hashtable_iterate_limit(table, data, 0, UINT_MAX, iterate);
+}
+
+unsigned int hashtable_counter(const struct hashtable *table)
+{
+	return table->count;
+}