diff --git a/libisofs/exclude.c b/libisofs/exclude.c
new file mode 100644
index 0000000..7aa84d9
--- /dev/null
+++ b/libisofs/exclude.c
@@ -0,0 +1,65 @@
+/***************************************************************************
+ *            exclude.c
+ *
+ *  Copyright  2006  Philippe Rouquier
+ *  Bonfire-app@wanadoo.fr
+ ***************************************************************************/
+
+/*
+ *  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 Library 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include "hash.h"
+#include "exclude.h"
+
+static struct iso_hash_node *table[HASH_NODES]={0,};
+static int num=0;
+
+void
+iso_exclude_add_path(const char *path)
+{
+	if (!path)
+		return;
+
+	num += iso_hash_insert(table, path);
+}
+
+void
+iso_exclude_remove_path(const char *path)
+{
+	if (!num || !path)
+		return;
+
+	num -= iso_hash_remove(table, path);
+}
+
+void
+iso_exclude_empty(void)
+{
+	if (!num)
+		return;
+
+	iso_hash_empty(table);
+	num=0;
+}
+
+int
+iso_exclude_lookup(const char *path)
+{
+	if (!num || !path)
+		return 0;
+
+	return iso_hash_lookup(table, path);
+}
diff --git a/libisofs/exclude.h b/libisofs/exclude.h
new file mode 100644
index 0000000..1d162e2
--- /dev/null
+++ b/libisofs/exclude.h
@@ -0,0 +1,35 @@
+/***************************************************************************
+ *            exclude.h
+ *
+ *  Copyright  2006  Philippe Rouquier
+ *  Bonfire-app@wanadoo.fr
+ ***************************************************************************/
+
+/*
+ *  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 Library 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#ifndef ISO_EXCLUDE_H
+#define ISO_EXCLUDE_H
+
+/**
+ * Add a path to ignore when adding a directory recursively.
+ *
+ * \param path The path, on the local filesystem, of the file.
+ */
+int
+iso_exclude_lookup(const char *path);
+
+#endif /* ISO_EXCLUDE */
diff --git a/libisofs/hash.c b/libisofs/hash.c
new file mode 100644
index 0000000..5bff22b
--- /dev/null
+++ b/libisofs/hash.c
@@ -0,0 +1,181 @@
+/***************************************************************************
+ *            hash.c
+ *
+ *  Copyright  2006  Philippe Rouquier
+ *  Bonfire-app@wanadoo.fr
+ ***************************************************************************/
+
+/*
+ *  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 Library 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "hash.h"
+
+static unsigned int
+iso_hash_path(const char *path)
+{
+	unsigned int hash_num=0;
+	const char *c;
+
+	c=path;
+	while(*c)
+		hash_num = (hash_num << 15) + (hash_num << 3) + (hash_num >> 3) + *c++;
+
+	return hash_num % HASH_NODES;
+}
+
+int
+iso_hash_lookup(struct iso_hash_node **table, const char *path)
+{
+	struct iso_hash_node *node;
+	unsigned int hash_num;
+
+	hash_num = iso_hash_path(path);
+
+	node=table[hash_num];
+
+	if (!node)
+		return 0;
+
+	if (!strcmp(path, node->path))
+		return 1;	
+
+	while (node->next) {
+		node=node->next;
+
+		if (!strcmp(path, node->path))
+			return 1;
+	}
+
+	return 0;
+ }
+
+static struct iso_hash_node*
+iso_hash_node_new (const char *path)
+{
+	struct iso_hash_node *node;
+
+	/*create an element to be inserted in the hash table */
+	node=malloc(sizeof(struct iso_hash_node));
+	node->path=strdup(path);
+	node->next=NULL;
+
+	return node;
+}
+
+int
+iso_hash_insert(struct iso_hash_node **table, const char *path)
+{
+	struct iso_hash_node *node;
+	unsigned int hash_num;
+
+	/* find the hash number */
+	hash_num = iso_hash_path(path);
+
+	/* insert it */
+	node = table[hash_num];
+
+	/* unfortunately, we can't safely consider that a path
+	 * won't be twice in the hash table so make sure it
+	 * doesn't already exists */
+	if (!node) {
+		table[hash_num]=iso_hash_node_new(path);
+		return 1;
+	}
+
+	/* if it's already in, we don't do anything */
+	if (!strcmp(path, node->path))
+		return 0;
+
+	while (node->next) {
+		node = node->next;
+
+		/* if it's already in, we don't do anything */
+		if (!strcmp (path, node->path))
+			return 0;
+	}
+
+	node->next = iso_hash_node_new(path);
+	return 1;
+}
+
+static void
+iso_hash_node_free(struct iso_hash_node *node)
+{
+	free(node->path);
+	free(node);
+}
+
+int
+iso_hash_remove(struct iso_hash_node **table,  const char *path)
+{
+	unsigned int hash_num;
+	struct iso_hash_node *node;
+
+	hash_num = iso_hash_path(path);
+
+	node=table[hash_num];
+	if (!node)
+		return 0;
+
+	if (!strcmp(path, node->path)) {
+		table[hash_num]=node->next;
+		iso_hash_node_free(node);
+		return 1;	
+	}
+
+	while (node->next) {
+		struct iso_hash_node *prev;
+
+		prev = node;
+		node = node->next;
+
+		if (!strcmp (path, node->path)) {
+			prev->next=node->next;
+			iso_hash_node_free(node);
+			return 1;
+		}
+	}
+
+	return 0;
+}
+
+void 
+iso_hash_empty(struct iso_hash_node **table)
+{
+	int i;
+
+	for (i=0; i < HASH_NODES; i++) {
+		struct iso_hash_node *node;
+
+		node=table[i];
+		if (!node)
+			continue;
+
+		table[i]=NULL;
+
+		do {
+			struct iso_hash_node *next;
+
+			next=node->next;
+			iso_hash_node_free(node);
+			node=next;
+		} while (node);
+	}
+}
+ 
diff --git a/libisofs/hash.h b/libisofs/hash.h
new file mode 100644
index 0000000..11d3bed
--- /dev/null
+++ b/libisofs/hash.h
@@ -0,0 +1,69 @@
+/***************************************************************************
+ *            hash.h
+ *
+ *  Copyright  2006  Philippe Rouquier
+ *  Bonfire-app@wanadoo.fr
+ ***************************************************************************/
+
+/*
+ *  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 Library 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., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#ifndef ISO_HASH_H
+#define ISO_HASH_H
+
+struct iso_hash_node {
+	struct iso_hash_node *next;
+	char *path;
+};
+
+#define HASH_NODES	128
+
+/**
+ * Searches in the hash table if the path exists.
+ *
+ * \param table The hash table.
+ * \param path The path of the file to look for.
+ *
+ * \return 1 if the path exists in the hash table, 0 otherwise.
+ */
+int iso_hash_lookup(struct iso_hash_node **table, const char *path);
+
+/**
+ * Insert a new path in the hash table.
+ *
+ * \param table The hash table.
+ * \param path The path of a file to add to the hash table.
+ *
+ * \return 1 if the file wasn't already in the hash table, 0 otherwise.
+ */
+int iso_hash_insert(struct iso_hash_node **table, const char *path);
+
+/**
+ * Remove a path from the hash table.
+ *
+ * \param table The hash table.
+ * \param path The path of a file to remove from the hash table.
+ *
+ * \return 1 if the file was found and removed, 0 otherwise.
+ */
+int iso_hash_remove(struct iso_hash_node **table, const char *path);
+
+/**
+ * Empty the hash table.
+ */
+void iso_hash_empty(struct iso_hash_node **table);
+
+#endif /* ISO_HASH_H */