[nautilus-actions: 5/30] Move NAIIOProvider interface to api/

[Pierre Wieser <pwieser src gnome org>]

commit 511e280284db7e373e14cc5951097b7fc43b33bf
Author: Pierre Wieser <pwieser trychlos org>
Date:   Wed Nov 18 00:51:26 2009 +0100

    Move NAIIOProvider interface to api/
    
    Introducing runtime/na-io-provider.{c,h} to handle internal API to NAIIOProvider interface.

 ChangeLog                                          |   32 ++
 nautilus-actions/api/Makefile.am                   |    3 +
 nautilus-actions/api/na-api.h                      |    2 +-
 nautilus-actions/api/na-gconf-keys.h               |    2 +-
 nautilus-actions/api/na-iio-provider.c             |  153 ++++++++++
 .../{runtime => api}/na-iio-provider.h             |   82 +++---
 nautilus-actions/common/Makefile.am                |    1 +
 nautilus-actions/nact/Makefile.am                  |    4 +-
 nautilus-actions/nact/nact-assistant-import.c      |    1 -
 nautilus-actions/nact/nact-main-window.c           |    1 -
 nautilus-actions/nact/nact-window.c                |   28 +-
 nautilus-actions/nact/nact-window.h                |    2 +-
 nautilus-actions/plugin/Makefile.am                |    1 +
 nautilus-actions/runtime/Makefile.am               |    5 +-
 nautilus-actions/runtime/na-gconf-provider.c       |  150 +++++-----
 .../{na-iio-provider.c => na-io-provider.c}        |  307 ++++++-------------
 nautilus-actions/runtime/na-io-provider.h          |   57 ++++
 nautilus-actions/runtime/na-module.c               |    7 +-
 nautilus-actions/runtime/na-module.h               |    2 +-
 nautilus-actions/runtime/na-object-item-fn.h       |    3 +-
 nautilus-actions/runtime/na-pivot.c                |   51 +++-
 nautilus-actions/runtime/na-pivot.h                |    5 +-
 nautilus-actions/test/Makefile.am                  |    4 +-
 nautilus-actions/utils/Makefile.am                 |    7 +-
 nautilus-actions/utils/nautilus-actions-new.c      |   12 +-
 25 files changed, 553 insertions(+), 369 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index 7ccd111..8b6a72d 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,10 +1,42 @@
 2009-11-17 Pierre Wieser <pwieser trychlos org>
 
+	Move NAIIOProvider interface to api/.
+
+	* nautilus-actions/api/na-api.h:
+	* nautilus-actions/api/na-gconf-keys.h: Fix doc typo.
+
+	* nautilus-actions/nact/nact-assistant-import.c:
+	* nautilus-actions/nact/nact-main-window.c:
+	* nautilus-actions/nact/nact-window.c:
+	* nautilus-actions/nact/nact-window.h:
+	* nautilus-actions/runtime/na-gconf-provider.c:
+	* nautilus-actions/runtime/na-object-item-fn.h:
+	* nautilus-actions/runtime/na-pivot.c:
+	* nautilus-actions/runtime/na-pivot.h:
+	* nautilus-actions/utils/nautilus-actions-new.c: Updated accordingly,
+	modifying path to headers,
+	fixing calls to NAIIOProvider interface.
+
+	* nautilus-actions/runtime/na-module.c:
+	* nautilus-actions/runtime/na-module.h: Fix typo.
+
+	* nautilus-actions/api/Makefile.am:
+	* nautilus-actions/common/Makefile.am:
+	* nautilus-actions/nact/Makefile.am:
+	* nautilus-actions/plugin/Makefile.am:
+	* nautilus-actions/runtime/Makefile.am:
+	* nautilus-actions/test/Makefile.am:
+	* nautilus-actions/utils/Makefile.am: Updated accordingly,
+	adding -I $(top_srcdir),
+	adding -L$(top_builddir)/nautilus-actions/api -lna-api.
+
 	Dynamically loads Nautilus-Actions extensions.
 
 	* nautilus-actions/runtime/na-module.c:
 	* nautilus-actions/runtime/na-module.h: New files.
 
+	* nautilus-actions/runtime/na-pivot.c: Load modules.
+
 	* nautilus-actions/runtime/Makefile.am: Updated accordingly.
 
 	Make libna-runtime a dynamically loaded library.
diff --git a/nautilus-actions/api/Makefile.am b/nautilus-actions/api/Makefile.am
index 83f8e4c..7315414 100644
--- a/nautilus-actions/api/Makefile.am
+++ b/nautilus-actions/api/Makefile.am
@@ -29,6 +29,7 @@
 pkglib_LTLIBRARIES=libna-api.la
 
 AM_CPPFLAGS += \
+	-I $(top_srcdir)									\
 	$(NAUTILUS_ACTIONS_CFLAGS)							\
 	-DG_LOG_DOMAIN=\"${NA_LOGDOMAIN_API}\"				\
 	$(NULL)
@@ -38,9 +39,11 @@ libna_api_includedir = $(pkgincludedir)/api
 libna_api_include_HEADERS = \
 	na-api.h											\
 	na-gconf-keys.h										\
+	na-iio-provider.h									\
 	$(NULL)
 
 libna_api_la_SOURCES = \
+	na-iio-provider.c									\
 	$(NULL)
 
 libna_api_la_LIBADD = \
diff --git a/nautilus-actions/api/na-api.h b/nautilus-actions/api/na-api.h
index d881d58..5c6fb84 100644
--- a/nautilus-actions/api/na-api.h
+++ b/nautilus-actions/api/na-api.h
@@ -34,7 +34,7 @@
 /**
  * SECTION: na_api
  * @short_description: #NAAPI interface definition.
- * @include: api/na-api.h
+ * @include: nautilus-actions/api/na-api.h
  *
  * These are common functions a Nautilus-Actions extension should
  * implement in order to be dynamically registered and identified.
diff --git a/nautilus-actions/api/na-gconf-keys.h b/nautilus-actions/api/na-gconf-keys.h
index dd74c10..db04984 100644
--- a/nautilus-actions/api/na-gconf-keys.h
+++ b/nautilus-actions/api/na-gconf-keys.h
@@ -34,7 +34,7 @@
 /**
  * SECTION: na_gconf
  * @short_description: GConf general information.
- * @include: nautilus-actions/na-gconf-keys.h
+ * @include: nautilus-actions/api/na-gconf-keys.h
  *
  * These keys are used both:
  * - by GConf as a NAIIOProvider
diff --git a/nautilus-actions/api/na-iio-provider.c b/nautilus-actions/api/na-iio-provider.c
new file mode 100644
index 0000000..d566ba8
--- /dev/null
+++ b/nautilus-actions/api/na-iio-provider.c
@@ -0,0 +1,153 @@
+/*
+ * Nautilus Actions
+ * A Nautilus extension which offers configurable context menu actions.
+ *
+ * Copyright (C) 2005 The GNOME Foundation
+ * Copyright (C) 2006, 2007, 2008 Frederic Ruaudel and others (see AUTHORS)
+ * Copyright (C) 2009 Pierre Wieser and others (see AUTHORS)
+ *
+ * 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 Library; see the file COPYING.  If not,
+ * write to the Free Software Foundation, Inc., 59 Temple Place,
+ * Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Authors:
+ *   Frederic Ruaudel <grumz grumz net>
+ *   Rodrigo Moya <rodrigo gnome-db org>
+ *   Pierre Wieser <pwieser trychlos org>
+ *   ... and many others (see AUTHORS)
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "na-iio-provider.h"
+
+/* private interface data
+ */
+struct NAIIOProviderInterfacePrivate {
+	void *empty;						/* so that gcc -pedantic is happy */
+};
+
+static gboolean st_initialized = FALSE;
+static gboolean st_finalized = FALSE;
+
+static GType    register_type( void );
+static void     interface_base_init( NAIIOProviderInterface *klass );
+static void     interface_base_finalize( NAIIOProviderInterface *klass );
+
+static gboolean do_is_willing_to_write( const NAIIOProvider *instance );
+static gboolean do_is_writable( const NAIIOProvider *instance, const NAObjectItem *item );
+
+/**
+ * Registers the GType of this interface.
+ */
+GType
+na_iio_provider_get_type( void )
+{
+	static GType object_type = 0;
+
+	if( !object_type ){
+		object_type = register_type();
+	}
+
+	return( object_type );
+}
+
+static GType
+register_type( void )
+{
+	static const gchar *thisfn = "na_iio_provider_register_type";
+	GType type;
+
+	static const GTypeInfo info = {
+		sizeof( NAIIOProviderInterface ),
+		( GBaseInitFunc ) interface_base_init,
+		( GBaseFinalizeFunc ) interface_base_finalize,
+		NULL,
+		NULL,
+		NULL,
+		0,
+		0,
+		NULL
+	};
+
+	g_debug( "%s", thisfn );
+
+	type = g_type_register_static( G_TYPE_INTERFACE, "NAIIOProvider", &info, 0 );
+
+	g_type_interface_add_prerequisite( type, G_TYPE_OBJECT );
+
+	return( type );
+}
+
+static void
+interface_base_init( NAIIOProviderInterface *klass )
+{
+	static const gchar *thisfn = "na_iio_provider_interface_base_init";
+
+	if( !st_initialized ){
+		g_debug( "%s: klass=%p", thisfn, ( void * ) klass );
+
+		klass->private = g_new0( NAIIOProviderInterfacePrivate, 1 );
+
+		klass->read_items = NULL;
+		klass->is_willing_to_write = do_is_willing_to_write;
+		klass->is_writable = do_is_writable;
+		klass->write_item = NULL;
+		klass->delete_item = NULL;
+
+		st_initialized = TRUE;
+	}
+}
+
+static void
+interface_base_finalize( NAIIOProviderInterface *klass )
+{
+	static const gchar *thisfn = "na_iio_provider_interface_base_finalize";
+
+	if( !st_finalized ){
+
+		st_finalized = TRUE;
+
+		g_debug( "%s: klass=%p", thisfn, ( void * ) klass );
+
+		g_free( klass->private );
+	}
+}
+
+static gboolean
+do_is_willing_to_write( const NAIIOProvider *instance )
+{
+	return( FALSE );
+}
+
+static gboolean
+do_is_writable( const NAIIOProvider *instance, const NAObjectItem *item )
+{
+	return( FALSE );
+}
+
+/**
+ * na_iio_provider_config_changed:
+ * @instance: the calling NAIIOProvider.
+ *
+ * Advertises Nautilus-Actions that this #NAIIOProvider @instance has
+ * detected a modification in one of its configurations (menu or action).
+ */
+void
+na_iio_provider_config_changed( const NAIIOProvider *instance )
+{
+
+}
diff --git a/nautilus-actions/runtime/na-iio-provider.h b/nautilus-actions/api/na-iio-provider.h
similarity index 61%
rename from nautilus-actions/runtime/na-iio-provider.h
rename to nautilus-actions/api/na-iio-provider.h
index fc0907b..7ebf11a 100644
--- a/nautilus-actions/runtime/na-iio-provider.h
+++ b/nautilus-actions/api/na-iio-provider.h
@@ -28,23 +28,19 @@
  *   ... and many others (see AUTHORS)
  */
 
-#ifndef __NA_RUNTIME_IIO_PROVIDER_H__
-#define __NA_RUNTIME_IIO_PROVIDER_H__
+#ifndef __NAUTILUS_ACTIONS_NA_IIO_PROVIDER_H__
+#define __NAUTILUS_ACTIONS_NA_IIO_PROVIDER_H__
 
 /**
  * SECTION: na_iio_provider
  * @short_description: #NAIIOProvider interface definition.
- * @include: runtime/na-iio-provider.h
+ * @include: nautilus-actions/api/na-iio-provider.h
  *
- * This is the API all storage subsystems should implement in order to
- * provide I/O resources to NautilusActions.
- *
- * In a near or far future, provider subsystems may be extended by
- * creating extension libraries, this class loading the modules at
- * startup time (e.g. on the model of provider interfaces in Nautilus).
+ * This is the API all I/O Providers should implement in order to
+ * provide I/O storage resources to Nautilus-Actions.
  */
 
-#include "na-pivot.h"
+#include <nautilus-actions/runtime/na-object-item-class.h>
 
 G_BEGIN_DECLS
 
@@ -61,16 +57,23 @@ typedef struct {
 	GTypeInterface                 parent;
 	NAIIOProviderInterfacePrivate *private;
 
+	/*
+	 * This is the API the provider has to implement.
+	 */
+
 	/**
-	 * read_items_list:
+	 * read_items:
 	 * @instance: the #NAIIOProvider provider.
+	 * @messages: a pointer to a #GSList which has been initialized to
+	 * NULL before calling this function ; the provider may append error
+	 * messages to this list, but shouldn't reinitialize it.
 	 *
 	 * Reads the whole items list from the specified I/O provider.
 	 *
-	 * Returns: a unordered #GSList of menus, actions and
-	 * profiles as #NAObject-derived objects.
+	 * Returns: a unordered flat #GList of NAObjectItem-derived objects
+	 * (menus or actions) ; the actions embed their own profiles.
 	 */
-	GList *  ( *read_items_list )    ( const NAIIOProvider *instance );
+	GList *  ( *read_items )         ( const NAIIOProvider *instance, GSList **messages );
 
 	/**
 	 * is_willing_to_write:
@@ -78,8 +81,8 @@ typedef struct {
 	 *
 	 * Checks for global writability of the I/O provider.
 	 *
-	 * Returns: %TRUE if we are able to update/write/delete a #NAAction
-	 * into this I/O provider, %FALSE else.
+	 * Returns: %TRUE if we are able to update/write/delete a #NAObjectItem
+	 * (menu or action) into this I/O provider, %FALSE else.
 	 *
 	 * Note that the I/O provider may return a positive writability
 	 * flag when considering the whole I/O storage subsystem, while not
@@ -90,54 +93,59 @@ typedef struct {
 	/**
 	 * is_writable:
 	 * @instance: the #NAIIOProvider provider.
-	 * @item: a #NAObject action or menu.
+	 * @item: a #NAObjectItem-derived menu or action.
 	 *
 	 * Checks for writability of this particular @item.
 	 *
 	 * Returns: %TRUE if we are able to update/write/delete the
 	 * @item, %FALSE else.
 	 */
-	gboolean ( *is_writable )        ( const NAIIOProvider *instance, const NAObject *item );
+	gboolean ( *is_writable )        ( const NAIIOProvider *instance, const NAObjectItem *item );
 
 	/**
-	 * write_tree_item:
+	 * write_item:
 	 * @instance: the #NAIIOProvider provider.
-	 * @item: a #NAObject to be written.
-	 * @message: warning/error messages detected in the operation.
+	 * @item: a #NAObjectItem-derived menu or action.
+	 * @messages: a pointer to a #GSList which has been initialized to
+	 * NULL before calling this function ; the provider may append error
+	 * messages to this list, but shouldn't reinitialize it.
 	 *
-	 * Updates an existing @item or writes a new one.
+	 * Writes a new @item.
 	 *
-	 * Returns: %NA_IIO_PROVIDER_WRITE_OK if the update/write operation
+	 * Returns: %NA_IIO_PROVIDER_WRITE_OK if the write operation
 	 * was successfull, or another code depending of the detected error.
+	 *
+	 * Note: there is no update_item function ; it is the responsability
+	 * of the provider to delete the previous version of an item before
+	 * writing the new version.
 	 */
-	guint    ( *write_item )         ( const NAIIOProvider *instance, NAObject *item, gchar **message );
+	guint    ( *write_item )         ( const NAIIOProvider *instance, const NAObjectItem *item, GSList **messages );
 
 	/**
-	 * delete_tree_item:
+	 * delete_item:
 	 * @instance: the #NAIIOProvider provider.
-	 * @item: a #NAObject to be deleted.
-	 * @message: warning/error messages detected in the operation.
+	 * @item: a #NAObjectItem-derived menu or action.
+	 * @messages: a pointer to a #GSList which has been initialized to
+	 * NULL before calling this function ; the provider may append error
+	 * messages to this list, but shouldn't reinitialize it.
 	 *
 	 * Deletes an existing @item from the I/O subsystem.
 	 *
 	 * Returns: %NA_IIO_PROVIDER_WRITE_OK if the delete operation was
 	 * successfull, or another code depending of the detected error.
 	 */
-	guint    ( *delete_item )        ( const NAIIOProvider *instance, const NAObject *item, gchar **message );
+	guint    ( *delete_item )        ( const NAIIOProvider *instance, const NAObjectItem *item, GSList **messages );
 }
 	NAIIOProviderInterface;
 
-GType  na_iio_provider_get_type( void );
-
-GList *na_iio_provider_get_items_tree( const NAPivot *pivot );
-guint  na_iio_provider_write_item( const NAPivot *pivot, NAObject *item, gchar **message );
-guint  na_iio_provider_delete_item( const NAPivot *pivot, const NAObject *item, gchar **message );
+GType na_iio_provider_get_type       ( void );
 
-/* notification message to NAPivot
+/* This function is to be called by the I/O provider when it detects a
+ * modification of one of its objects in its underlying storage subsystem.
  */
-#define NA_IIO_PROVIDER_SIGNAL_ACTION_CHANGED			"notify-consumer-of-action-change"
+void  na_iio_provider_config_changed ( const NAIIOProvider *instance );
 
-/* return code of update/write/delete operations
+/* return code of write/delete operations
  */
 enum {
 	NA_IIO_PROVIDER_WRITE_OK = 0,
@@ -150,4 +158,4 @@ enum {
 
 G_END_DECLS
 
-#endif /* __NA_RUNTIME_IIO_PROVIDER_H__ */
+#endif /* __NAUTILUS_ACTIONS_NA_IIO_PROVIDER_H__ */
diff --git a/nautilus-actions/common/Makefile.am b/nautilus-actions/common/Makefile.am
index bcabf6a..84ceac0 100644
--- a/nautilus-actions/common/Makefile.am
+++ b/nautilus-actions/common/Makefile.am
@@ -29,6 +29,7 @@
 noinst_LTLIBRARIES = libna-common.la
 
 AM_CPPFLAGS += \
+	-I $(top_srcdir)							\
 	-I $(top_srcdir)/nautilus-actions			\
 	-DGNOMELOCALEDIR=\""$(datadir)/locale"\"	\
 	-DG_LOG_DOMAIN=\"${NA_LOGDOMAIN_COMMON}\"	\
diff --git a/nautilus-actions/nact/Makefile.am b/nautilus-actions/nact/Makefile.am
index a5b037f..21cb09f 100644
--- a/nautilus-actions/nact/Makefile.am
+++ b/nautilus-actions/nact/Makefile.am
@@ -31,6 +31,7 @@ bin_PROGRAMS = \
 	$(NULL)
 
 AM_CPPFLAGS += \
+	-I $(top_srcdir)											\
 	-I $(top_srcdir)/nautilus-actions							\
 	-DGNOMELOCALEDIR=\""$(datadir)/locale"\"					\
 	-DPKGDATADIR=\"$(pkgdatadir)\"								\
@@ -113,7 +114,8 @@ nact-marshal.c: nact-marshal.list $(GLIB_GENMARSHAL)
 
 nautilus_actions_config_tool_LDADD = \
 	$(top_builddir)/nautilus-actions/common/libna-common.la		\
-	-L$(top_builddir)/nautilus-actions/runtime -lna-runtime		\
+	-L$(top_builddir)/nautilus-actions/api		-lna-api		\
+	-L$(top_builddir)/nautilus-actions/runtime	-lna-runtime	\
 	$(NAUTILUS_ACTIONS_LIBS)									\
 	$(NULL)
 
diff --git a/nautilus-actions/nact/nact-assistant-import.c b/nautilus-actions/nact/nact-assistant-import.c
index 5d78b42..9ebd181 100644
--- a/nautilus-actions/nact/nact-assistant-import.c
+++ b/nautilus-actions/nact/nact-assistant-import.c
@@ -37,7 +37,6 @@
 #include <gtk/gtk.h>
 #include <string.h>
 
-#include <runtime/na-iio-provider.h>
 #include <runtime/na-pivot.h>
 
 #include <common/na-object-api.h>
diff --git a/nautilus-actions/nact/nact-main-window.c b/nautilus-actions/nact/nact-main-window.c
index c67ca6f..360cd86 100644
--- a/nautilus-actions/nact/nact-main-window.c
+++ b/nautilus-actions/nact/nact-main-window.c
@@ -39,7 +39,6 @@
 
 #include <runtime/na-pivot.h>
 #include <runtime/na-iabout.h>
-#include <runtime/na-iio-provider.h>
 #include <runtime/na-ipivot-consumer.h>
 
 #include <common/na-object-api.h>
diff --git a/nautilus-actions/nact/nact-window.c b/nautilus-actions/nact/nact-window.c
index 1da7d29..e1a2f7d 100644
--- a/nautilus-actions/nact/nact-window.c
+++ b/nautilus-actions/nact/nact-window.c
@@ -35,7 +35,7 @@
 #include <glib.h>
 #include <glib/gi18n.h>
 
-#include <runtime/na-iio-provider.h>
+#include <api/na-iio-provider.h>
 
 #include <common/na-object-api.h>
 #include <common/na-iprefs.h>
@@ -214,7 +214,7 @@ nact_window_save_item( NactWindow *window, NAObjectItem *item )
 	static const gchar *thisfn = "nact_window_save_item";
 	gboolean save_ok = FALSE;
 	NAPivot *pivot;
-	gchar *msg = NULL;
+	GSList *messages = NULL;
 	guint ret;
 
 	g_debug( "%s: window=%p, item=%p (%s)", thisfn,
@@ -229,13 +229,15 @@ nact_window_save_item( NactWindow *window, NAObjectItem *item )
 
 		na_object_dump( item );
 
-		ret = na_pivot_write_item( pivot, NA_OBJECT( item ), &msg );
+		ret = na_pivot_write_item( pivot, item, &messages );
 
-		if( msg ){
+		if( messages ){
 			base_window_error_dlg(
 					BASE_WINDOW( window ),
-					GTK_MESSAGE_WARNING, _( "An error has occured when trying to save the item" ), msg );
-			g_free( msg );
+					GTK_MESSAGE_WARNING,
+					_( "An error has occured when trying to save the item" ),
+					( const gchar * ) messages->data );
+			na_utils_free_string_list( messages );
 		}
 
 		save_ok = ( ret == NA_IIO_PROVIDER_WRITE_OK );
@@ -252,12 +254,12 @@ nact_window_save_item( NactWindow *window, NAObjectItem *item )
  * Deleted an item from the I/O storage subsystem.
  */
 gboolean
-nact_window_delete_item( NactWindow *window, NAObjectItem *item )
+nact_window_delete_item( NactWindow *window, const NAObjectItem *item )
 {
 	static const gchar *thisfn = "nact_window_delete_item";
 	gboolean delete_ok = FALSE;
 	NAPivot *pivot;
-	gchar *msg = NULL;
+	GSList *messages = NULL;
 	guint ret;
 
 	g_debug( "%s: window=%p, item=%p (%s)", thisfn,
@@ -272,13 +274,15 @@ nact_window_delete_item( NactWindow *window, NAObjectItem *item )
 
 		na_object_dump_norec( item );
 
-		ret = na_pivot_delete_item( pivot, NA_OBJECT( item ), &msg );
+		ret = na_pivot_delete_item( pivot, item, &messages );
 
-		if( msg ){
+		if( messages ){
 			base_window_error_dlg(
 					BASE_WINDOW( window ),
-					GTK_MESSAGE_WARNING, _( "An error has occured when trying to delete the item" ), msg );
-			g_free( msg );
+					GTK_MESSAGE_WARNING,
+					_( "An error has occured when trying to delete the item" ),
+					( const gchar * ) messages->data );
+			na_utils_free_string_list( messages );
 		}
 
 		delete_ok = ( ret == NA_IIO_PROVIDER_WRITE_OK );
diff --git a/nautilus-actions/nact/nact-window.h b/nautilus-actions/nact/nact-window.h
index 91a4c6d..067ef8a 100644
--- a/nautilus-actions/nact/nact-window.h
+++ b/nautilus-actions/nact/nact-window.h
@@ -75,7 +75,7 @@ GType    nact_window_get_type( void );
 NAPivot *nact_window_get_pivot( NactWindow *window );
 
 gboolean nact_window_save_item( NactWindow *window, NAObjectItem *item );
-gboolean nact_window_delete_item( NactWindow *window, NAObjectItem *item );
+gboolean nact_window_delete_item( NactWindow *window, const NAObjectItem *item );
 
 void     nact_window_count_level_zero_items( GList *items, guint *actions, guint *profiles, guint *menus );
 
diff --git a/nautilus-actions/plugin/Makefile.am b/nautilus-actions/plugin/Makefile.am
index dfa14fc..0253fa0 100644
--- a/nautilus-actions/plugin/Makefile.am
+++ b/nautilus-actions/plugin/Makefile.am
@@ -27,6 +27,7 @@
 #   ... and many others (see AUTHORS)
 
 AM_CPPFLAGS += \
+	-I $(top_srcdir)											\
 	-I $(top_srcdir)/nautilus-actions							\
 	-DG_LOG_DOMAIN=\"${NA_LOGDOMAIN_PLUGIN}\"					\
 	$(NAUTILUS_ACTIONS_CFLAGS)									\
diff --git a/nautilus-actions/runtime/Makefile.am b/nautilus-actions/runtime/Makefile.am
index b97e7a7..a2f8e68 100644
--- a/nautilus-actions/runtime/Makefile.am
+++ b/nautilus-actions/runtime/Makefile.am
@@ -29,6 +29,7 @@
 pkglib_LTLIBRARIES = libna-runtime.la
 
 AM_CPPFLAGS += \
+	-I $(top_srcdir)							\
 	-DPKGLIBDIR=\""$(pkglibdir)"\"				\
 	-DGNOMELOCALEDIR=\""$(datadir)/locale"\"	\
 	-DG_LOG_DOMAIN=\"${NA_LOGDOMAIN_RUNTIME}\"	\
@@ -50,8 +51,8 @@ libna_runtime_la_SOURCES = \
 	na-iabout.h									\
 	na-iduplicable.c							\
 	na-iduplicable.h							\
-	na-iio-provider.c							\
-	na-iio-provider.h							\
+	na-io-provider.c							\
+	na-io-provider.h							\
 	na-ipivot-consumer.c						\
 	na-ipivot-consumer.h						\
 	na-iprefs.c									\
diff --git a/nautilus-actions/runtime/na-gconf-provider.c b/nautilus-actions/runtime/na-gconf-provider.c
index 4a5e69c..a0be710 100644
--- a/nautilus-actions/runtime/na-gconf-provider.c
+++ b/nautilus-actions/runtime/na-gconf-provider.c
@@ -39,7 +39,6 @@
 #include "na-gconf-provider.h"
 #include "na-gconf-provider-keys.h"
 #include "na-gconf-utils.h"
-#include "na-iio-provider.h"
 #include "na-utils.h"
 
 /* private class data
@@ -70,7 +69,7 @@ static void           install_monitors( NAGConfProvider *provider );
 static void           config_path_changed_cb( GConfClient *client, guint cnxn_id, GConfEntry *entry, NAGConfProvider *provider );
 static NAPivotNotify *entry_to_notify( const GConfEntry *entry );
 
-static GList         *iio_provider_read_items_list( const NAIIOProvider *provider );
+static GList         *iio_provider_read_items( const NAIIOProvider *provider, GSList **messages );
 static NAObjectItem  *read_item( NAGConfProvider *provider, const gchar *path );
 static void           read_item_action( NAGConfProvider *provider, const gchar *path, NAObjectAction *action );
 static void           read_item_action_properties( NAGConfProvider *provider, GSList *entries, NAObjectAction *action );
@@ -83,20 +82,20 @@ static void           read_object_item_properties( NAGConfProvider *provider, GS
 
 static gboolean       iio_provider_is_willing_to_write( const NAIIOProvider *provider );
 
-static gboolean       iio_provider_is_writable( const NAIIOProvider *provider, const NAObject *item );
+static gboolean       iio_provider_is_writable( const NAIIOProvider *provider, const NAObjectItem *item );
 
-static guint          iio_provider_write_item( const NAIIOProvider *provider, NAObject *item, gchar **message );
-static gboolean       write_item_action( NAGConfProvider *gconf, const NAObjectAction *action, gchar **message );
-static gboolean       write_item_menu( NAGConfProvider *gconf, const NAObjectMenu *menu, gchar **message );
-static gboolean       write_object_item( NAGConfProvider *gconf, const NAObjectItem *item, gchar **message );
+static guint          iio_provider_write_item( const NAIIOProvider *provider, const NAObjectItem *item, GSList **messages );
+static gboolean       write_item_action( NAGConfProvider *gconf, const NAObjectAction *action, GSList **messages );
+static gboolean       write_item_menu( NAGConfProvider *gconf, const NAObjectMenu *menu, GSList **messages );
+static gboolean       write_object_item( NAGConfProvider *gconf, const NAObjectItem *item, GSList **messages );
 
-static guint          iio_provider_delete_item( const NAIIOProvider *provider, const NAObject *item, gchar **message );
+static guint          iio_provider_delete_item( const NAIIOProvider *provider, const NAObjectItem *item, GSList **messages );
 
 static gboolean       key_is_writable( NAGConfProvider *gconf, const gchar *path );
 
-static gboolean       write_str( NAGConfProvider *gconf, const gchar *uuid, const gchar *name, const gchar *key, gchar *value, gchar **message );
-static gboolean       write_bool( NAGConfProvider *gconf, const gchar *uuid, const gchar *name, const gchar *key, gboolean value, gchar **message );
-static gboolean       write_list( NAGConfProvider *gconf, const gchar *uuid, const gchar *name, const gchar *key, GSList *value, gchar **message );
+static gboolean       write_str( NAGConfProvider *gconf, const gchar *uuid, const gchar *name, const gchar *key, gchar *value, GSList **messages );
+static gboolean       write_bool( NAGConfProvider *gconf, const gchar *uuid, const gchar *name, const gchar *key, gboolean value, GSList **messages );
+static gboolean       write_list( NAGConfProvider *gconf, const gchar *uuid, const gchar *name, const gchar *key, GSList *value, GSList **messages );
 
 GType
 na_gconf_provider_get_type( void )
@@ -167,7 +166,7 @@ iio_provider_iface_init( NAIIOProviderInterface *iface )
 
 	g_debug( "%s: iface=%p", thisfn, ( void * ) iface );
 
-	iface->read_items_list = iio_provider_read_items_list;
+	iface->read_items = iio_provider_read_items;
 	iface->is_willing_to_write = iio_provider_is_willing_to_write;
 	iface->is_writable = iio_provider_is_writable;
 	iface->write_item = iio_provider_write_item;
@@ -328,7 +327,8 @@ config_path_changed_cb( GConfClient *client, guint cnxn_id, GConfEntry *entry, N
 
 	if( !provider->private->dispose_has_run ){
 		npn = entry_to_notify( entry );
-		g_signal_emit_by_name( provider->private->pivot, NA_IIO_PROVIDER_SIGNAL_ACTION_CHANGED, npn );
+		/*g_signal_emit_by_name( provider->private->pivot, NA_IIO_PROVIDER_SIGNAL_ACTION_CHANGED, npn );*/
+		na_iio_provider_config_changed( NA_IIO_PROVIDER( provider ));
 	}
 }
 
@@ -428,15 +428,15 @@ entry_to_notify( const GConfEntry *entry )
  * latest, version of these classes.
  */
 static GList *
-iio_provider_read_items_list( const NAIIOProvider *provider )
+iio_provider_read_items( const NAIIOProvider *provider, GSList **messages )
 {
-	static const gchar *thisfn = "na_gconf_provider_iio_provider_read_items_list";
+	static const gchar *thisfn = "na_gconf_provider_iio_provider_read_items";
 	NAGConfProvider *self;
 	GList *items_list = NULL;
 	GSList *listpath, *ip;
 	NAObjectItem *item;
 
-	g_debug( "%s: provider=%p", thisfn, ( void * ) provider );
+	g_debug( "%s: provider=%p, messages=%p", thisfn, ( void * ) provider, ( void * ) messages );
 
 	g_return_val_if_fail( NA_IS_IIO_PROVIDER( provider ), NULL );
 	g_return_val_if_fail( NA_IS_GCONF_PROVIDER( provider ), NULL );
@@ -814,7 +814,7 @@ iio_provider_is_willing_to_write( const NAIIOProvider *provider )
 }
 
 static gboolean
-iio_provider_is_writable( const NAIIOProvider *provider, const NAObject *item )
+iio_provider_is_writable( const NAIIOProvider *provider, const NAObjectItem *item )
 {
 	NAGConfProvider *self;
 	gboolean willing_to = FALSE;
@@ -833,49 +833,43 @@ iio_provider_is_writable( const NAIIOProvider *provider, const NAObject *item )
 }
 
 static guint
-iio_provider_write_item( const NAIIOProvider *provider, NAObject *item, gchar **message )
+iio_provider_write_item( const NAIIOProvider *provider, const NAObjectItem *item, GSList **messages )
 {
 	static const gchar *thisfn = "na_gconf_provider_iio_provider_write_item";
 	NAGConfProvider *self;
 
-	g_debug( "%s: provider=%p, item=%p (%s), message=%p",
+	g_debug( "%s: provider=%p, item=%p (%s), messages=%p",
 			thisfn, ( void * ) provider,
-			( void * ) item, G_OBJECT_TYPE_NAME( item ), ( void * ) message );
+			( void * ) item, G_OBJECT_TYPE_NAME( item ), ( void * ) messages );
 	g_return_val_if_fail( NA_IS_GCONF_PROVIDER( provider ), NA_IIO_PROVIDER_PROGRAM_ERROR );
 	g_return_val_if_fail( NA_IS_IIO_PROVIDER( provider ), NA_IIO_PROVIDER_PROGRAM_ERROR );
 	g_return_val_if_fail( NA_IS_OBJECT_ITEM( item ), NA_IIO_PROVIDER_PROGRAM_ERROR );
 
 	self = NA_GCONF_PROVIDER( provider );
 
-	if( message ){
-		*message = NULL;
-	}
-
 	if( self->private->dispose_has_run ){
 		return( NA_IIO_PROVIDER_NOT_WILLING_TO_WRITE );
 	}
 
 	if( NA_IS_OBJECT_ACTION( item )){
-		if( !write_item_action( self, NA_OBJECT_ACTION( item ), message )){
+		if( !write_item_action( self, NA_OBJECT_ACTION( item ), messages )){
 			return( NA_IIO_PROVIDER_WRITE_ERROR );
 		}
 	}
 
 	if( NA_IS_OBJECT_MENU( item )){
-		if( !write_item_menu( self, NA_OBJECT_MENU( item ), message )){
+		if( !write_item_menu( self, NA_OBJECT_MENU( item ), messages )){
 			return( NA_IIO_PROVIDER_WRITE_ERROR );
 		}
 	}
 
 	gconf_client_suggest_sync( self->private->gconf, NULL );
 
-	na_object_set_provider( item, provider );
-
 	return( NA_IIO_PROVIDER_WRITE_OK );
 }
 
 static gboolean
-write_item_action( NAGConfProvider *provider, const NAObjectAction *action, gchar **message )
+write_item_action( NAGConfProvider *provider, const NAObjectAction *action, GSList **messages )
 {
 	gchar *uuid, *name;
 	gboolean ret;
@@ -885,14 +879,14 @@ write_item_action( NAGConfProvider *provider, const NAObjectAction *action, gcha
 	uuid = na_object_get_id( action );
 
 	ret =
-		write_object_item( provider, NA_OBJECT_ITEM( action ), message ) &&
-		write_str( provider, uuid, NULL, ACTION_VERSION_ENTRY, na_object_action_get_version( action ), message ) &&
-		write_bool( provider, uuid, NULL, OBJECT_ITEM_TARGET_SELECTION_ENTRY, na_object_action_is_target_selection( action ), message ) &&
-		write_bool( provider, uuid, NULL, OBJECT_ITEM_TARGET_BACKGROUND_ENTRY, na_object_action_is_target_background( action ), message ) &&
-		write_bool( provider, uuid, NULL, OBJECT_ITEM_TARGET_TOOLBAR_ENTRY, na_object_action_is_target_toolbar( action ), message ) &&
-		write_bool( provider, uuid, NULL, OBJECT_ITEM_TOOLBAR_SAME_LABEL_ENTRY, na_object_action_toolbar_use_same_label( action ), message ) &&
-		write_str( provider, uuid, NULL, OBJECT_ITEM_TOOLBAR_LABEL_ENTRY, na_object_action_toolbar_get_label( action ), message ) &&
-		write_str( provider, uuid, NULL, OBJECT_ITEM_TYPE_ENTRY, g_strdup( OBJECT_ITEM_TYPE_ACTION ), message );
+		write_object_item( provider, NA_OBJECT_ITEM( action ), messages ) &&
+		write_str( provider, uuid, NULL, ACTION_VERSION_ENTRY, na_object_action_get_version( action ), messages ) &&
+		write_bool( provider, uuid, NULL, OBJECT_ITEM_TARGET_SELECTION_ENTRY, na_object_action_is_target_selection( action ), messages ) &&
+		write_bool( provider, uuid, NULL, OBJECT_ITEM_TARGET_BACKGROUND_ENTRY, na_object_action_is_target_background( action ), messages ) &&
+		write_bool( provider, uuid, NULL, OBJECT_ITEM_TARGET_TOOLBAR_ENTRY, na_object_action_is_target_toolbar( action ), messages ) &&
+		write_bool( provider, uuid, NULL, OBJECT_ITEM_TOOLBAR_SAME_LABEL_ENTRY, na_object_action_toolbar_use_same_label( action ), messages ) &&
+		write_str( provider, uuid, NULL, OBJECT_ITEM_TOOLBAR_LABEL_ENTRY, na_object_action_toolbar_get_label( action ), messages ) &&
+		write_str( provider, uuid, NULL, OBJECT_ITEM_TYPE_ENTRY, g_strdup( OBJECT_ITEM_TYPE_ACTION ), messages );
 
 	profiles = na_object_get_items_list( action );
 
@@ -902,17 +896,17 @@ write_item_action( NAGConfProvider *provider, const NAObjectAction *action, gcha
 		name = na_object_get_id( profile );
 
 		ret =
-			write_str( provider, uuid, name, ACTION_PROFILE_LABEL_ENTRY, na_object_get_label( profile ), message ) &&
-			write_str( provider, uuid, name, ACTION_PATH_ENTRY, na_object_profile_get_path( profile ), message ) &&
-			write_str( provider, uuid, name, ACTION_PARAMETERS_ENTRY, na_object_profile_get_parameters( profile ), message ) &&
-			write_list( provider, uuid, name, ACTION_BASENAMES_ENTRY, na_object_profile_get_basenames( profile ), message ) &&
-			write_bool( provider, uuid, name, ACTION_MATCHCASE_ENTRY, na_object_profile_get_matchcase( profile ), message ) &&
-			write_list( provider, uuid, name, ACTION_MIMETYPES_ENTRY, na_object_profile_get_mimetypes( profile ), message ) &&
-			write_bool( provider, uuid, name, ACTION_ISFILE_ENTRY, na_object_profile_get_is_file( profile ), message ) &&
-			write_bool( provider, uuid, name, ACTION_ISDIR_ENTRY, na_object_profile_get_is_dir( profile ), message ) &&
-			write_bool( provider, uuid, name, ACTION_MULTIPLE_ENTRY, na_object_profile_get_multiple( profile ), message ) &&
-			write_list( provider, uuid, name, ACTION_SCHEMES_ENTRY, na_object_profile_get_schemes( profile ), message ) &&
-			write_list( provider, uuid, name, ACTION_FOLDERS_ENTRY, na_object_profile_get_folders( profile ), message );
+			write_str( provider, uuid, name, ACTION_PROFILE_LABEL_ENTRY, na_object_get_label( profile ), messages ) &&
+			write_str( provider, uuid, name, ACTION_PATH_ENTRY, na_object_profile_get_path( profile ), messages ) &&
+			write_str( provider, uuid, name, ACTION_PARAMETERS_ENTRY, na_object_profile_get_parameters( profile ), messages ) &&
+			write_list( provider, uuid, name, ACTION_BASENAMES_ENTRY, na_object_profile_get_basenames( profile ), messages ) &&
+			write_bool( provider, uuid, name, ACTION_MATCHCASE_ENTRY, na_object_profile_get_matchcase( profile ), messages ) &&
+			write_list( provider, uuid, name, ACTION_MIMETYPES_ENTRY, na_object_profile_get_mimetypes( profile ), messages ) &&
+			write_bool( provider, uuid, name, ACTION_ISFILE_ENTRY, na_object_profile_get_is_file( profile ), messages ) &&
+			write_bool( provider, uuid, name, ACTION_ISDIR_ENTRY, na_object_profile_get_is_dir( profile ), messages ) &&
+			write_bool( provider, uuid, name, ACTION_MULTIPLE_ENTRY, na_object_profile_get_multiple( profile ), messages ) &&
+			write_list( provider, uuid, name, ACTION_SCHEMES_ENTRY, na_object_profile_get_schemes( profile ), messages ) &&
+			write_list( provider, uuid, name, ACTION_FOLDERS_ENTRY, na_object_profile_get_folders( profile ), messages );
 
 		g_free( name );
 	}
@@ -923,7 +917,7 @@ write_item_action( NAGConfProvider *provider, const NAObjectAction *action, gcha
 }
 
 static gboolean
-write_item_menu( NAGConfProvider *provider, const NAObjectMenu *menu, gchar **message )
+write_item_menu( NAGConfProvider *provider, const NAObjectMenu *menu, GSList **messages )
 {
 	gboolean ret;
 	gchar *uuid;
@@ -931,8 +925,8 @@ write_item_menu( NAGConfProvider *provider, const NAObjectMenu *menu, gchar **me
 	uuid = na_object_get_id( menu );
 
 	ret =
-		write_object_item( provider, NA_OBJECT_ITEM( menu ), message ) &&
-		write_str( provider, uuid, NULL, OBJECT_ITEM_TYPE_ENTRY, g_strdup( OBJECT_ITEM_TYPE_MENU ), message );
+		write_object_item( provider, NA_OBJECT_ITEM( menu ), messages ) &&
+		write_str( provider, uuid, NULL, OBJECT_ITEM_TYPE_ENTRY, g_strdup( OBJECT_ITEM_TYPE_MENU ), messages );
 
 	g_free( uuid );
 
@@ -940,7 +934,7 @@ write_item_menu( NAGConfProvider *provider, const NAObjectMenu *menu, gchar **me
 }
 
 static gboolean
-write_object_item( NAGConfProvider *provider, const NAObjectItem *item, gchar **message )
+write_object_item( NAGConfProvider *provider, const NAObjectItem *item, GSList **messages )
 {
 	gchar *uuid;
 	gboolean ret;
@@ -948,11 +942,11 @@ write_object_item( NAGConfProvider *provider, const NAObjectItem *item, gchar **
 	uuid = na_object_get_id( NA_OBJECT( item ));
 
 	ret =
-		write_str( provider, uuid, NULL, OBJECT_ITEM_LABEL_ENTRY, na_object_get_label( NA_OBJECT( item )), message ) &&
-		write_str( provider, uuid, NULL, OBJECT_ITEM_TOOLTIP_ENTRY, na_object_get_tooltip( item ), message ) &&
-		write_str( provider, uuid, NULL, OBJECT_ITEM_ICON_ENTRY, na_object_get_icon( item ), message ) &&
-		write_bool( provider, uuid, NULL, OBJECT_ITEM_ENABLED_ENTRY, na_object_is_enabled( item ), message ) &&
-		write_list( provider, uuid, NULL, OBJECT_ITEM_LIST_ENTRY, na_object_item_rebuild_items_list( item ), message );
+		write_str( provider, uuid, NULL, OBJECT_ITEM_LABEL_ENTRY, na_object_get_label( NA_OBJECT( item )), messages ) &&
+		write_str( provider, uuid, NULL, OBJECT_ITEM_TOOLTIP_ENTRY, na_object_get_tooltip( item ), messages ) &&
+		write_str( provider, uuid, NULL, OBJECT_ITEM_ICON_ENTRY, na_object_get_icon( item ), messages ) &&
+		write_bool( provider, uuid, NULL, OBJECT_ITEM_ENABLED_ENTRY, na_object_is_enabled( item ), messages ) &&
+		write_list( provider, uuid, NULL, OBJECT_ITEM_LIST_ENTRY, na_object_item_rebuild_items_list( item ), messages );
 
 	g_free( uuid );
 	return( ret );
@@ -963,7 +957,7 @@ write_object_item( NAGConfProvider *provider, const NAObjectItem *item, gchar **
  * cf. http://bugzilla.gnome.org/show_bug.cgi?id=325585
  */
 static guint
-iio_provider_delete_item( const NAIIOProvider *provider, const NAObject *item, gchar **message )
+iio_provider_delete_item( const NAIIOProvider *provider, const NAObjectItem *item, GSList **messages )
 {
 	static const gchar *thisfn = "na_gconf_provider_iio_provider_delete_item";
 	NAGConfProvider *self;
@@ -971,9 +965,9 @@ iio_provider_delete_item( const NAIIOProvider *provider, const NAObject *item, g
 	gchar *uuid, *path;
 	GError *error = NULL;
 
-	g_debug( "%s: provider=%p, item=%p (%s), message=%p",
+	g_debug( "%s: provider=%p, item=%p (%s), messages=%p",
 			thisfn, ( void * ) provider,
-			( void * ) item, G_OBJECT_TYPE_NAME( item ), ( void * ) message );
+			( void * ) item, G_OBJECT_TYPE_NAME( item ), ( void * ) messages );
 
 	g_return_val_if_fail( NA_IS_IIO_PROVIDER( provider ), NA_IIO_PROVIDER_PROGRAM_ERROR );
 	g_return_val_if_fail( NA_IS_GCONF_PROVIDER( provider ), NA_IIO_PROVIDER_PROGRAM_ERROR );
@@ -985,10 +979,6 @@ iio_provider_delete_item( const NAIIOProvider *provider, const NAObject *item, g
 		return( NA_IIO_PROVIDER_NOT_WILLING_TO_WRITE );
 	}
 
-	if( message ){
-		*message = NULL;
-	}
-
 	ret = NA_IIO_PROVIDER_WRITE_OK;
 	uuid = na_object_get_id( NA_OBJECT( item ));
 
@@ -1005,7 +995,7 @@ iio_provider_delete_item( const NAIIOProvider *provider, const NAObject *item, g
 	path = g_strdup_printf( "%s/%s", NA_GCONF_CONFIG_PATH, uuid );
 	if( !gconf_client_recursive_unset( self->private->gconf, path, 0, &error )){
 		g_warning( "%s: path=%s, error=%s", thisfn, path, error->message );
-		*message = g_strdup( error->message );
+		/* TODO: *message = g_strdup( error->message );*/
 		g_error_free( error );
 		ret = NA_IIO_PROVIDER_WRITE_ERROR;
 
@@ -1075,10 +1065,11 @@ key_is_writable( NAGConfProvider *gconf, const gchar *path )
 }
 
 static gboolean
-write_str( NAGConfProvider *provider, const gchar *uuid, const gchar *name, const gchar *key, gchar *value, gchar **message )
+write_str( NAGConfProvider *provider, const gchar *uuid, const gchar *name, const gchar *key, gchar *value, GSList **messages )
 {
 	gchar *path;
 	gboolean ret;
+	gchar *msg;
 
 	if( name && strlen( name )){
 		path = g_strdup_printf( "%s/%s/%s/%s", NA_GCONF_CONFIG_PATH, uuid, name, key );
@@ -1086,7 +1077,12 @@ write_str( NAGConfProvider *provider, const gchar *uuid, const gchar *name, cons
 		path = g_strdup_printf( "%s/%s/%s", NA_GCONF_CONFIG_PATH, uuid, key );
 	}
 
-	ret = na_gconf_utils_write_string( provider->private->gconf, path, value, message );
+	msg = NULL;
+	ret = na_gconf_utils_write_string( provider->private->gconf, path, value, &msg );
+	if( msg ){
+		*messages = g_slist_append( *messages, msg );
+		g_free( msg );
+	}
 
 	g_free( value );
 	g_free( path );
@@ -1095,10 +1091,11 @@ write_str( NAGConfProvider *provider, const gchar *uuid, const gchar *name, cons
 }
 
 static gboolean
-write_bool( NAGConfProvider *provider, const gchar *uuid, const gchar *name, const gchar *key, gboolean value, gchar **message )
+write_bool( NAGConfProvider *provider, const gchar *uuid, const gchar *name, const gchar *key, gboolean value, GSList **messages )
 {
 	gboolean ret;
 	gchar *path;
+	gchar *msg;
 
 	if( name && strlen( name )){
 		path = g_strdup_printf( "%s/%s/%s/%s", NA_GCONF_CONFIG_PATH, uuid, name, key );
@@ -1106,7 +1103,12 @@ write_bool( NAGConfProvider *provider, const gchar *uuid, const gchar *name, con
 		path = g_strdup_printf( "%s/%s/%s", NA_GCONF_CONFIG_PATH, uuid, key );
 	}
 
-	ret = na_gconf_utils_write_bool( provider->private->gconf, path, value, message );
+	msg = NULL;
+	ret = na_gconf_utils_write_bool( provider->private->gconf, path, value, &msg );
+	if( msg ){
+		*messages = g_slist_append( *messages, msg );
+		g_free( msg );
+	}
 
 	g_free( path );
 
@@ -1114,10 +1116,11 @@ write_bool( NAGConfProvider *provider, const gchar *uuid, const gchar *name, con
 }
 
 static gboolean
-write_list( NAGConfProvider *provider, const gchar *uuid, const gchar *name, const gchar *key, GSList *value, gchar **message )
+write_list( NAGConfProvider *provider, const gchar *uuid, const gchar *name, const gchar *key, GSList *value, GSList **messages )
 {
 	gboolean ret;
 	gchar *path;
+	gchar *msg;
 
 	if( name && strlen( name )){
 		path = g_strdup_printf( "%s/%s/%s/%s", NA_GCONF_CONFIG_PATH, uuid, name, key );
@@ -1125,7 +1128,12 @@ write_list( NAGConfProvider *provider, const gchar *uuid, const gchar *name, con
 		path = g_strdup_printf( "%s/%s/%s", NA_GCONF_CONFIG_PATH, uuid, key );
 	}
 
-	ret = na_gconf_utils_write_string_list( provider->private->gconf, path, value, message );
+	msg = NULL;
+	ret = na_gconf_utils_write_string_list( provider->private->gconf, path, value, &msg );
+	if( msg ){
+		*messages = g_slist_append( *messages, msg );
+		g_free( msg );
+	}
 
 	na_utils_free_string_list( value );
 	g_free( path );
diff --git a/nautilus-actions/runtime/na-iio-provider.c b/nautilus-actions/runtime/na-io-provider.c
similarity index 52%
rename from nautilus-actions/runtime/na-iio-provider.c
rename to nautilus-actions/runtime/na-io-provider.c
index aca2d65..5a57d61 100644
--- a/nautilus-actions/runtime/na-iio-provider.c
+++ b/nautilus-actions/runtime/na-io-provider.c
@@ -34,116 +34,26 @@
 
 #include <string.h>
 
+#include <nautilus-actions/api/na-iio-provider.h>
+
 #include "na-object-api.h"
-#include "na-iio-provider.h"
+#include "na-io-provider.h"
 #include "na-iprefs.h"
 #include "na-utils.h"
 
-/* private interface data
- */
-struct NAIIOProviderInterfacePrivate {
-	void *empty;						/* so that gcc -pedantic is happy */
-};
-
-static gboolean st_initialized = FALSE;
-static gboolean st_finalized = FALSE;
-
-static GType    register_type( void );
-static void     interface_base_init( NAIIOProviderInterface *klass );
-static void     interface_base_finalize( NAIIOProviderInterface *klass );
-
 static GList   *build_hierarchy( GList **tree, GSList *level_zero, gboolean list_if_empty );
 static gint     search_item( const NAObject *obj, const gchar *uuid );
-static GList   *get_merged_items_list( const NAPivot *pivot, GList *providers );
-
-static guint    try_write_item( const NAIIOProvider *instance, NAObject *item, gchar **message );
+static GList   *get_merged_items_list( const NAPivot *pivot, GList *providers, GSList **messages );
 
-static gboolean do_is_willing_to_write( const NAIIOProvider *instance );
-static gboolean do_is_writable( const NAIIOProvider *instance, const NAObject *item );
+static guint    try_write_item( const NAIIOProvider *instance, NAObjectItem *item, GSList **messages );
 
 static GList   *sort_tree( const NAPivot *pivot, GList *tree, GCompareFunc fn );
 
 /**
- * Registers the GType of this interface.
- */
-GType
-na_iio_provider_get_type( void )
-{
-	static GType object_type = 0;
-
-	if( !object_type ){
-		object_type = register_type();
-	}
-
-	return( object_type );
-}
-
-static GType
-register_type( void )
-{
-	static const gchar *thisfn = "na_iio_provider_register_type";
-	GType type;
-
-	static const GTypeInfo info = {
-		sizeof( NAIIOProviderInterface ),
-		( GBaseInitFunc ) interface_base_init,
-		( GBaseFinalizeFunc ) interface_base_finalize,
-		NULL,
-		NULL,
-		NULL,
-		0,
-		0,
-		NULL
-	};
-
-	g_debug( "%s", thisfn );
-
-	type = g_type_register_static( G_TYPE_INTERFACE, "NAIIOProvider", &info, 0 );
-
-	g_type_interface_add_prerequisite( type, G_TYPE_OBJECT );
-
-	return( type );
-}
-
-static void
-interface_base_init( NAIIOProviderInterface *klass )
-{
-	static const gchar *thisfn = "na_iio_provider_interface_base_init";
-
-	if( !st_initialized ){
-		g_debug( "%s: klass=%p", thisfn, ( void * ) klass );
-
-		klass->private = g_new0( NAIIOProviderInterfacePrivate, 1 );
-
-		klass->read_items_list = NULL;
-		klass->is_willing_to_write = do_is_willing_to_write;
-		klass->is_writable = do_is_writable;
-		klass->write_item = NULL;
-		klass->delete_item = NULL;
-
-		st_initialized = TRUE;
-	}
-}
-
-static void
-interface_base_finalize( NAIIOProviderInterface *klass )
-{
-	static const gchar *thisfn = "na_iio_provider_interface_base_finalize";
-
-	if( !st_finalized ){
-
-		st_finalized = TRUE;
-
-		g_debug( "%s: klass=%p", thisfn, ( void * ) klass );
-
-		g_free( klass->private );
-	}
-}
-
-/**
- * na_iio_provider_get_items_tree:
+ * na_io_provider_read_items:
  * @pivot: the #NAPivot object which owns the list of registered I/O
  * storage providers.
+ * @messages: error messages.
  *
  * Loads the tree from I/O storage subsystems.
  *
@@ -152,62 +62,60 @@ interface_base_finalize( NAIIOProviderInterface *klass )
  * #NAAction actions and their #NAActionProfile profiles.
  */
 GList *
-na_iio_provider_get_items_tree( const NAPivot *pivot )
+na_io_provider_read_items( const NAPivot *pivot, GSList **messages )
 {
-	static const gchar *thisfn = "na_iio_provider_get_items_tree";
+	static const gchar *thisfn = "na_io_provider_read_items";
 	GList *providers;
 	GList *merged, *hierarchy;
 	GSList *level_zero;
 	gint order_mode;
 
-	g_debug( "%s: pivot=%p", thisfn, ( void * ) pivot );
+	g_debug( "%s: pivot=%p, messages=%p", thisfn, ( void * ) pivot, ( void * ) messages );
 	g_return_val_if_fail( NA_IS_PIVOT( pivot ), NULL );
 	g_return_val_if_fail( NA_IS_IPREFS( pivot ), NULL );
 
 	hierarchy = NULL;
+	*messages = NULL;
 
-	if( st_initialized && !st_finalized ){
-
-		providers = na_pivot_get_providers( pivot, NA_IIO_PROVIDER_TYPE );
-		merged = get_merged_items_list( pivot, providers );
-		na_pivot_free_providers( providers );
+	providers = na_pivot_get_providers( pivot, NA_IIO_PROVIDER_TYPE );
+	merged = get_merged_items_list( pivot, providers, messages );
+	na_pivot_free_providers( providers );
 
-		level_zero = na_iprefs_get_level_zero_items( NA_IPREFS( pivot ));
-		hierarchy = build_hierarchy( &merged, level_zero, TRUE );
+	level_zero = na_iprefs_get_level_zero_items( NA_IPREFS( pivot ));
+	hierarchy = build_hierarchy( &merged, level_zero, TRUE );
 
-		/* items that stay left in the merged list are simply appended
-		 * to the built hierarchy, and level zero is updated accordingly
-		 */
-		if( merged ){
-			g_debug( "%s: %d items left appended to the hierarchy", thisfn, g_list_length( merged ));
-			hierarchy = g_list_concat( hierarchy, merged );
-		}
+	/* items that stay left in the merged list are simply appended
+	 * to the built hierarchy, and level zero is updated accordingly
+	 */
+	if( merged ){
+		g_debug( "%s: %d items left appended to the hierarchy", thisfn, g_list_length( merged ));
+		hierarchy = g_list_concat( hierarchy, merged );
+	}
 
-		if( merged || !level_zero || !g_slist_length( level_zero )){
-			g_debug( "%s: rewriting level-zero", thisfn );
-			na_pivot_write_level_zero( pivot, hierarchy );
-		}
+	if( merged || !level_zero || !g_slist_length( level_zero )){
+		g_debug( "%s: rewriting level-zero", thisfn );
+		na_pivot_write_level_zero( pivot, hierarchy );
+	}
 
-		na_utils_free_string_list( level_zero );
+	na_utils_free_string_list( level_zero );
 
-		g_debug( "%s: tree before alphabetical reordering (if any)", thisfn );
-		na_object_dump_tree( hierarchy );
-		g_debug( "%s: end of tree", thisfn );
+	g_debug( "%s: tree before alphabetical reordering (if any)", thisfn );
+	na_object_dump_tree( hierarchy );
+	g_debug( "%s: end of tree", thisfn );
 
-		order_mode = na_iprefs_get_order_mode( NA_IPREFS( pivot ));
-		switch( order_mode ){
-			case IPREFS_ORDER_ALPHA_ASCENDING:
-				hierarchy = sort_tree( pivot, hierarchy, ( GCompareFunc ) na_pivot_sort_alpha_asc );
-				break;
+	order_mode = na_iprefs_get_order_mode( NA_IPREFS( pivot ));
+	switch( order_mode ){
+		case IPREFS_ORDER_ALPHA_ASCENDING:
+			hierarchy = sort_tree( pivot, hierarchy, ( GCompareFunc ) na_pivot_sort_alpha_asc );
+			break;
 
-			case IPREFS_ORDER_ALPHA_DESCENDING:
-				hierarchy = sort_tree( pivot, hierarchy, ( GCompareFunc ) na_pivot_sort_alpha_desc );
-				break;
+		case IPREFS_ORDER_ALPHA_DESCENDING:
+			hierarchy = sort_tree( pivot, hierarchy, ( GCompareFunc ) na_pivot_sort_alpha_desc );
+			break;
 
-			case IPREFS_ORDER_MANUAL:
-			default:
-				break;
-		}
+		case IPREFS_ORDER_MANUAL:
+		default:
+			break;
 	}
 
 	return( hierarchy );
@@ -287,7 +195,7 @@ search_item( const NAObject *obj, const gchar *uuid )
  * returns a concatened list of readen actions / menus
  */
 static GList *
-get_merged_items_list( const NAPivot *pivot, GList *providers )
+get_merged_items_list( const NAPivot *pivot, GList *providers, GSList **messages )
 {
 	GList *ip;
 	GList *merged = NULL;
@@ -297,9 +205,9 @@ get_merged_items_list( const NAPivot *pivot, GList *providers )
 	for( ip = providers ; ip ; ip = ip->next ){
 
 		instance = NA_IIO_PROVIDER( ip->data );
-		if( NA_IIO_PROVIDER_GET_INTERFACE( instance )->read_items_list ){
+		if( NA_IIO_PROVIDER_GET_INTERFACE( instance )->read_items ){
 
-			list = NA_IIO_PROVIDER_GET_INTERFACE( instance )->read_items_list( instance );
+			list = NA_IIO_PROVIDER_GET_INTERFACE( instance )->read_items( instance, messages );
 
 			for( item = list ; item ; item = item->next ){
 
@@ -315,82 +223,78 @@ get_merged_items_list( const NAPivot *pivot, GList *providers )
 }
 
 /**
- * na_iio_provider_write_item:
+ * na_io_provider_write_item:
  * @pivot: the #NAPivot object which owns the list of registered I/O
  * storage providers. if NULL, @action must already have registered
  * its own provider.
- * @item: a #NAObject to be written by the storage subsystem.
- * @message: the I/O provider can allocate and store here an error
- * message.
+ * @item: a #NAObjectItem to be written by the storage subsystem.
+ * @messages: error messages.
  *
  * Writes an @item to a willing-to storage subsystem.
  *
  * Returns: the NAIIOProvider return code.
  */
 guint
-na_iio_provider_write_item( const NAPivot *pivot, NAObject *item, gchar **message )
+na_io_provider_write_item( const NAPivot *pivot, NAObjectItem *item, GSList **messages )
 {
-	static const gchar *thisfn = "na_iio_provider_write_item";
+	static const gchar *thisfn = "na_io_provider_write_item";
 	guint ret;
 	NAIIOProvider *instance;
 	NAIIOProvider *bad_instance;
 	GList *providers, *ip;
 
-	g_debug( "%s: pivot=%p (%s), item=%p (%s), message=%p", thisfn,
+	g_debug( "%s: pivot=%p (%s), item=%p (%s), messages=%p", thisfn,
 			( void * ) pivot, G_OBJECT_TYPE_NAME( pivot ),
 			( void * ) item, G_OBJECT_TYPE_NAME( item ),
-			( void * ) message );
+			( void * ) messages );
 
 	g_return_val_if_fail(( NA_IS_PIVOT( pivot ) || !pivot ), NA_IIO_PROVIDER_PROGRAM_ERROR );
 	g_return_val_if_fail( NA_IS_OBJECT_ITEM( item ), NA_IIO_PROVIDER_PROGRAM_ERROR );
 
-	ret = NA_IIO_PROVIDER_NOT_WILLING_TO_WRITE;
-
-	if( st_initialized && !st_finalized ){
+	ret = NA_IIO_PROVIDER_NOT_WRITABLE;
+	bad_instance = NULL;
+	*messages = NULL;
 
-		ret = NA_IIO_PROVIDER_NOT_WRITABLE;
-		bad_instance = NULL;
-
-		/* try to write to the original provider of the item
-		 */
-		instance = NA_IIO_PROVIDER( na_object_get_provider( item ));
-		if( instance ){
-			ret = try_write_item( instance, item, message );
-			if( ret == NA_IIO_PROVIDER_NOT_WILLING_TO_WRITE || ret == NA_IIO_PROVIDER_NOT_WRITABLE ){
-				bad_instance = instance;
-				instance = NULL;
-			}
+	/* try to write to the original provider of the item
+	 */
+	instance = NA_IIO_PROVIDER( na_object_get_provider( item ));
+	if( instance ){
+		ret = try_write_item( instance, item, messages );
+		if( ret == NA_IIO_PROVIDER_NOT_WILLING_TO_WRITE || ret == NA_IIO_PROVIDER_NOT_WRITABLE ){
+			bad_instance = instance;
+			instance = NULL;
 		}
+	}
 
-		/* else, search for a provider which is willing to write the item
-		 */
-		if( !instance && pivot ){
-			providers = na_pivot_get_providers( pivot, NA_IIO_PROVIDER_TYPE );
-			for( ip = providers ; ip ; ip = ip->next ){
-
-				instance = NA_IIO_PROVIDER( ip->data );
-				if( !bad_instance || bad_instance != instance ){
-					ret = try_write_item( instance, item, message );
-					if( ret == NA_IIO_PROVIDER_WRITE_OK ){
-						break;
-					}
+	/* else, search for a provider which is willing to write the item
+	 */
+	if( !instance && pivot ){
+		providers = na_pivot_get_providers( pivot, NA_IIO_PROVIDER_TYPE );
+		for( ip = providers ; ip ; ip = ip->next ){
+
+			instance = NA_IIO_PROVIDER( ip->data );
+			if( !bad_instance || instance != bad_instance ){
+				ret = try_write_item( instance, item, messages );
+				if( ret == NA_IIO_PROVIDER_WRITE_OK ){
+					na_object_set_provider( item, instance );
+					break;
 				}
 			}
-			na_pivot_free_providers( providers );
 		}
+		na_pivot_free_providers( providers );
 	}
 
 	return( ret );
 }
 
 static guint
-try_write_item( const NAIIOProvider *provider, NAObject *item, gchar **message )
+try_write_item( const NAIIOProvider *provider, NAObjectItem *item, GSList **messages )
 {
-	static const gchar *thisfn = "na_iio_provider_try_write_item";
+	static const gchar *thisfn = "na_io_provider_try_write_item";
 	guint ret;
 
-	g_debug( "%s: provider=%p, item=%p, message=%p",
-			thisfn, ( void * ) provider, ( void * ) item, ( void * ) message );
+	g_debug( "%s: provider=%p, item=%p, messages=%p",
+			thisfn, ( void * ) provider, ( void * ) item, ( void * ) messages );
 
 	if( !NA_IIO_PROVIDER_GET_INTERFACE( provider )->is_willing_to_write( provider )){
 		return( NA_IIO_PROVIDER_NOT_WILLING_TO_WRITE );
@@ -405,21 +309,20 @@ try_write_item( const NAIIOProvider *provider, NAObject *item, gchar **message )
 		return( NA_IIO_PROVIDER_NOT_WILLING_TO_WRITE );
 	}
 
-	ret = NA_IIO_PROVIDER_GET_INTERFACE( provider )->delete_item( provider, item, message );
+	ret = NA_IIO_PROVIDER_GET_INTERFACE( provider )->delete_item( provider, item, messages );
 	if( ret != NA_IIO_PROVIDER_WRITE_OK ){
 		return( ret );
 	}
 
-	return( NA_IIO_PROVIDER_GET_INTERFACE( provider )->write_item( provider, item, message ));
+	return( NA_IIO_PROVIDER_GET_INTERFACE( provider )->write_item( provider, item, messages ));
 }
 
 /**
- * na_iio_provider_delete_item:
+ * na_io_provider_delete_item:
  * @pivot: the #NAPivot object which owns the list of registered I/O
  * storage providers.
- * @item: the #NAObject item to be deleted.
- * @message: the I/O provider can allocate and store here an error
- * message.
+ * @item: the #NAObjectItem item to be deleted.
+ * @messages: error messages.
  *
  * Deletes an item (action or menu) from the storage subsystem.
  *
@@ -429,51 +332,35 @@ try_write_item( const NAIIOProvider *provider, NAObject *item, gchar **message )
  * doesn't have any attached provider. We so do nothing...
  */
 guint
-na_iio_provider_delete_item( const NAPivot *pivot, const NAObject *item, gchar **message )
+na_io_provider_delete_item( const NAPivot *pivot, const NAObjectItem *item, GSList **messages )
 {
-	static const gchar *thisfn = "na_iio_provider_delete_item";
+	static const gchar *thisfn = "na_io_provider_delete_item";
 	guint ret;
 	NAIIOProvider *instance;
 
-	g_debug( "%s: pivot=%p (%s), item=%p (%s), message=%p", thisfn,
+	g_debug( "%s: pivot=%p (%s), item=%p (%s), messages=%p", thisfn,
 			( void * ) pivot, G_OBJECT_TYPE_NAME( pivot ),
 			( void * ) item, G_OBJECT_TYPE_NAME( item ),
-			( void * ) message );
+			( void * ) messages );
 
 	g_return_val_if_fail( NA_IS_PIVOT( pivot ), NA_IIO_PROVIDER_PROGRAM_ERROR );
 	g_return_val_if_fail( NA_IS_OBJECT_ITEM( item ), NA_IIO_PROVIDER_PROGRAM_ERROR );
 
-	ret = NA_IIO_PROVIDER_NOT_WILLING_TO_WRITE;
-
-	if( st_initialized && !st_finalized ){
+	*messages = NULL;
+	ret = NA_IIO_PROVIDER_NOT_WRITABLE;
+	instance = NA_IIO_PROVIDER( na_object_get_provider( item ));
 
-		ret = NA_IIO_PROVIDER_NOT_WRITABLE;
-		instance = NA_IIO_PROVIDER( na_object_get_provider( item ));
+	if( instance ){
+		g_return_val_if_fail( NA_IS_IIO_PROVIDER( instance ), NA_IIO_PROVIDER_PROGRAM_ERROR );
 
-		if( instance ){
-			g_return_val_if_fail( NA_IS_IIO_PROVIDER( instance ), NA_IIO_PROVIDER_PROGRAM_ERROR );
-
-			if( NA_IIO_PROVIDER_GET_INTERFACE( instance )->delete_item ){
-				ret = NA_IIO_PROVIDER_GET_INTERFACE( instance )->delete_item( instance, item, message );
-			}
+		if( NA_IIO_PROVIDER_GET_INTERFACE( instance )->delete_item ){
+			ret = NA_IIO_PROVIDER_GET_INTERFACE( instance )->delete_item( instance, item, messages );
 		}
 	}
 
 	return( ret );
 }
 
-static gboolean
-do_is_willing_to_write( const NAIIOProvider *instance )
-{
-	return( FALSE );
-}
-
-static gboolean
-do_is_writable( const NAIIOProvider *instance, const NAObject *item )
-{
-	return( FALSE );
-}
-
 static GList *
 sort_tree( const NAPivot *pivot, GList *tree, GCompareFunc fn )
 {
diff --git a/nautilus-actions/runtime/na-io-provider.h b/nautilus-actions/runtime/na-io-provider.h
new file mode 100644
index 0000000..f3d5bae
--- /dev/null
+++ b/nautilus-actions/runtime/na-io-provider.h
@@ -0,0 +1,57 @@
+/*
+ * Nautilus Actions
+ * A Nautilus extension which offers configurable context menu actions.
+ *
+ * Copyright (C) 2005 The GNOME Foundation
+ * Copyright (C) 2006, 2007, 2008 Frederic Ruaudel and others (see AUTHORS)
+ * Copyright (C) 2009 Pierre Wieser and others (see AUTHORS)
+ *
+ * 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 Library; see the file COPYING.  If not,
+ * write to the Free Software Foundation, Inc., 59 Temple Place,
+ * Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Authors:
+ *   Frederic Ruaudel <grumz grumz net>
+ *   Rodrigo Moya <rodrigo gnome-db org>
+ *   Pierre Wieser <pwieser trychlos org>
+ *   ... and many others (see AUTHORS)
+ */
+
+#ifndef __NA_RUNTIME_IO_PROVIDER_H__
+#define __NA_RUNTIME_IO_PROVIDER_H__
+
+/**
+ * SECTION: na_iio_provider
+ * @short_description: #NAIIOProvider internal API.
+ * @include: runtime/na-io-provider.h
+ *
+ * This is the API which is used by Nautilus-Actions to manage the actual
+ * NAIIOProvider interface.
+ */
+
+#include "na-pivot.h"
+
+G_BEGIN_DECLS
+
+GList *na_io_provider_read_items ( const NAPivot *pivot, GSList **messages );
+guint  na_io_provider_write_item ( const NAPivot *pivot, NAObjectItem *item, GSList **messages );
+guint  na_io_provider_delete_item( const NAPivot *pivot, const NAObjectItem *item, GSList **messages );
+
+/* notification message to NAPivot
+ */
+#define NA_IIO_PROVIDER_SIGNAL_ACTION_CHANGED			"notify-consumer-of-action-change"
+
+G_END_DECLS
+
+#endif /* __NA_RUNTIME_IO_PROVIDER_H__ */
diff --git a/nautilus-actions/runtime/na-module.c b/nautilus-actions/runtime/na-module.c
index cbf3bc5..e6ecd21 100644
--- a/nautilus-actions/runtime/na-module.c
+++ b/nautilus-actions/runtime/na-module.c
@@ -261,7 +261,7 @@ module_unload( GTypeModule *gmodule )
 }
 
 /**
- * na_modules_load_modules:
+ * na_module_load_modules:
  *
  * Load availables dynamic libraries.
  *
@@ -269,9 +269,9 @@ module_unload( GTypeModule *gmodule )
  * loaded library.
  */
 GList *
-na_modules_load_modules( void )
+na_module_load_modules( void )
 {
-	static const gchar *thisfn = "na_modules_load_modules";
+	static const gchar *thisfn = "na_module_load_modules";
 	const gchar *dirname = PKGLIBDIR;
 	GList *modules;
 	GDir *api_dir;
@@ -298,6 +298,7 @@ na_modules_load_modules( void )
 				module = module_new( fname );
 				if( module ){
 					modules = g_list_prepend( modules, module );
+					g_debug( "%s: module %s successfully loaded", thisfn, fname );
 				}
 				g_free( fname );
 			}
diff --git a/nautilus-actions/runtime/na-module.h b/nautilus-actions/runtime/na-module.h
index b352e8a..388d541 100644
--- a/nautilus-actions/runtime/na-module.h
+++ b/nautilus-actions/runtime/na-module.h
@@ -70,7 +70,7 @@ typedef struct {
 
 GType  na_module_get_type               ( void );
 
-GList *na_modules_load_modules          ( void );
+GList *na_module_load_modules           ( void );
 GList *na_module_get_extensions_for_type( GList *modules, GType type );
 gchar *na_module_get_name               ( NAModule *module, GType type );
 void   na_module_release_modules        ( GList *modules );
diff --git a/nautilus-actions/runtime/na-object-item-fn.h b/nautilus-actions/runtime/na-object-item-fn.h
index 630da50..b10d58e 100644
--- a/nautilus-actions/runtime/na-object-item-fn.h
+++ b/nautilus-actions/runtime/na-object-item-fn.h
@@ -42,8 +42,9 @@
  * in na-object-api.h
  */
 
+#include <nautilus-actions/api/na-iio-provider.h>
+
 #include "na-object-item-class.h"
-#include "na-iio-provider.h"
 
 G_BEGIN_DECLS
 
diff --git a/nautilus-actions/runtime/na-pivot.c b/nautilus-actions/runtime/na-pivot.c
index fdffd59..5bd9daf 100644
--- a/nautilus-actions/runtime/na-pivot.c
+++ b/nautilus-actions/runtime/na-pivot.c
@@ -36,10 +36,11 @@
 #include <uuid/uuid.h>
 
 #include "na-object-api.h"
-#include "na-iio-provider.h"
+#include "na-io-provider.h"
 #include "na-gconf-monitor.h"
 #include "na-gconf-provider.h"
 #include "na-iprefs.h"
+#include "na-module.h"
 #include "na-pivot.h"
 #include "na-utils.h"
 
@@ -54,6 +55,10 @@ struct NAPivotClassPrivate {
 struct NAPivotPrivate {
 	gboolean dispose_has_run;
 
+	/* dynamically loaded modules
+	 */
+	GList   *modules;
+
 	/* list of instances to be notified of repository updates
 	 * these are called 'consumers' of NAPivot
 	 */
@@ -219,6 +224,7 @@ instance_init( GTypeInstance *instance, gpointer klass )
 	self->private = g_new0( NAPivotPrivate, 1 );
 
 	self->private->dispose_has_run = FALSE;
+	self->private->modules = NULL;
 	self->private->consumers = NULL;
 	self->private->providers = NULL;
 	self->private->tree = NULL;
@@ -239,6 +245,10 @@ instance_dispose( GObject *object )
 
 		self->private->dispose_has_run = TRUE;
 
+		/* release modules */
+		na_module_release_modules( self->private->modules );
+		self->private->modules = NULL;
+
 		/* release list of NAIPivotConsumers */
 		free_consumers( self->private->consumers );
 		self->private->consumers = NULL;
@@ -295,12 +305,15 @@ na_pivot_new( const NAIPivotConsumer *target )
 {
 	static const gchar *thisfn = "na_pivot_new";
 	NAPivot *pivot;
+	GSList *messages, *im;
 
 	g_debug( "%s: target=%p", thisfn, ( void * ) target );
 	g_return_val_if_fail( NA_IS_IPIVOT_CONSUMER( target ) || !target, NULL );
 
 	pivot = g_object_new( NA_PIVOT_TYPE, NULL );
 
+	pivot->private->modules = na_module_load_modules();
+
 	register_io_providers( pivot );
 
 	if( target ){
@@ -309,7 +322,11 @@ na_pivot_new( const NAIPivotConsumer *target )
 
 	monitor_runtime_preferences( pivot );
 
-	pivot->private->tree = na_iio_provider_get_items_tree( pivot );
+	pivot->private->tree = na_io_provider_read_items( pivot, &messages );
+	for( im = messages ; im ; im = im->next ){
+		g_warning( "%s: %s", thisfn, ( const gchar * ) im->data );
+	}
+	na_utils_free_string_list( messages );
 
 	return( pivot );
 }
@@ -352,6 +369,7 @@ na_pivot_dump( const NAPivot *pivot )
 
 	if( !pivot->private->dispose_has_run ){
 
+		g_debug( "%s:   modules=%p (%d elts)", thisfn, ( void * ) pivot->private->modules, g_list_length( pivot->private->modules ));
 		g_debug( "%s: consumers=%p (%d elts)", thisfn, ( void * ) pivot->private->consumers, g_list_length( pivot->private->consumers ));
 		g_debug( "%s: providers=%p (%d elts)", thisfn, ( void * ) pivot->private->providers, g_list_length( pivot->private->providers ));
 		g_debug( "%s:      tree=%p (%d elts)", thisfn, ( void * ) pivot->private->tree, g_list_length( pivot->private->tree ));
@@ -446,13 +464,20 @@ na_pivot_get_items( const NAPivot *pivot )
 void
 na_pivot_reload_items( NAPivot *pivot )
 {
+	static const gchar *thisfn = "na_pivot_reload_items";
+	GSList *messages, *im;
+
 	g_return_if_fail( NA_IS_PIVOT( pivot ));
 
 	if( !pivot->private->dispose_has_run ){
 
 		na_object_free_items_list( pivot->private->tree );
 
-		pivot->private->tree = na_iio_provider_get_items_tree( pivot );
+		pivot->private->tree = na_io_provider_read_items( pivot, &messages );
+		for( im = messages ; im ; im = im->next ){
+			g_warning( "%s: %s", thisfn, ( const gchar * ) im->data );
+		}
+		na_utils_free_string_list( messages );
 	}
 }
 
@@ -545,24 +570,24 @@ na_pivot_remove_item( NAPivot *pivot, NAObject *item )
  * na_pivot_delete_item:
  * @pivot: this #NAPivot instance.
  * @item: the #NAObjectItem to be deleted from the storage subsystem.
- * @message: the I/O provider can allocate and store here an error
- * message.
+ * @messages: the I/O provider can allocate and store here its error
+ * messages.
  *
  * Deletes an action from the I/O storage subsystem.
  *
  * Returns: the #NAIIOProvider return code.
  */
 guint
-na_pivot_delete_item( const NAPivot *pivot, const NAObject *item, gchar **message )
+na_pivot_delete_item( const NAPivot *pivot, const NAObjectItem *item, GSList **messages )
 {
 	guint ret = NA_IIO_PROVIDER_NOT_WILLING_TO_WRITE;
 
 	g_return_val_if_fail( NA_IS_PIVOT( pivot ), NA_IIO_PROVIDER_PROGRAM_ERROR );
 	g_return_val_if_fail( NA_IS_OBJECT_ITEM( item ), NA_IIO_PROVIDER_PROGRAM_ERROR );
-	g_return_val_if_fail( message, NA_IIO_PROVIDER_PROGRAM_ERROR );
+	g_return_val_if_fail( messages, NA_IIO_PROVIDER_PROGRAM_ERROR );
 
 	if( !pivot->private->dispose_has_run ){
-		ret = na_iio_provider_delete_item( pivot, item, message );
+		ret = na_io_provider_delete_item( pivot, item, messages );
 	}
 
 	return( ret );
@@ -572,24 +597,24 @@ na_pivot_delete_item( const NAPivot *pivot, const NAObject *item, gchar **messag
  * na_pivot_write_item:
  * @pivot: this #NAPivot instance.
  * @item: a #NAObjectItem to be written by the storage subsystem.
- * @message: the I/O provider can allocate and store here an error
- * message.
+ * @messages: the I/O provider can allocate and store here its error
+ * messages.
  *
  * Writes an item (an action or a menu).
  *
  * Returns: the #NAIIOProvider return code.
  */
 guint
-na_pivot_write_item( const NAPivot *pivot, NAObject *item, gchar **message )
+na_pivot_write_item( const NAPivot *pivot, NAObjectItem *item, GSList **messages )
 {
 	guint ret = NA_IIO_PROVIDER_NOT_WILLING_TO_WRITE;
 
 	g_return_val_if_fail( NA_IS_PIVOT( pivot ), NA_IIO_PROVIDER_PROGRAM_ERROR );
 	g_return_val_if_fail( NA_IS_OBJECT_ITEM( item ), NA_IIO_PROVIDER_PROGRAM_ERROR );
-	g_return_val_if_fail( message, NA_IIO_PROVIDER_PROGRAM_ERROR );
+	g_return_val_if_fail( messages, NA_IIO_PROVIDER_PROGRAM_ERROR );
 
 	if( !pivot->private->dispose_has_run ){
-		ret = na_iio_provider_write_item( pivot, item, message );
+		ret = na_io_provider_write_item( pivot, item, messages );
 	}
 
 	return( ret );
diff --git a/nautilus-actions/runtime/na-pivot.h b/nautilus-actions/runtime/na-pivot.h
index e7ea54a..e3da3e8 100644
--- a/nautilus-actions/runtime/na-pivot.h
+++ b/nautilus-actions/runtime/na-pivot.h
@@ -76,6 +76,7 @@
 
 #include "na-object-class.h"
 #include "na-object-id-class.h"
+#include "na-object-item-class.h"
 #include "na-ipivot-consumer.h"
 
 G_BEGIN_DECLS
@@ -119,8 +120,8 @@ void      na_pivot_add_item( NAPivot *pivot, const NAObject *item );
 NAObject *na_pivot_get_item( const NAPivot *pivot, const gchar *uuid );
 void      na_pivot_remove_item( NAPivot *pivot, NAObject *item );
 
-guint     na_pivot_delete_item( const NAPivot *pivot, const NAObject *item, gchar **message );
-guint     na_pivot_write_item( const NAPivot *pivot, NAObject *item, gchar **message );
+guint     na_pivot_delete_item( const NAPivot *pivot, const NAObjectItem *item, GSList **messages );
+guint     na_pivot_write_item( const NAPivot *pivot, NAObjectItem *item, GSList **messages );
 
 void      na_pivot_register_consumer( NAPivot *pivot, const NAIPivotConsumer *consumer );
 
diff --git a/nautilus-actions/test/Makefile.am b/nautilus-actions/test/Makefile.am
index d4ec998..fc89557 100644
--- a/nautilus-actions/test/Makefile.am
+++ b/nautilus-actions/test/Makefile.am
@@ -34,6 +34,7 @@ noinst_PROGRAMS = \
 	$(NULL)
 
 AM_CPPFLAGS += \
+	-I $(top_srcdir)											\
 	-I $(top_srcdir)/nautilus-actions							\
 	-DGNOMELOCALEDIR=\""$(datadir)/locale"\"					\
 	-DG_LOG_DOMAIN=\"${NA_LOGDOMAIN_TEST}\"						\
@@ -59,7 +60,8 @@ test_parse_uris_SOURCES = \
 	$(NULL)
 
 test_parse_uris_LDADD = \
-	-L$(top_builddir)/nautilus-actions/runtime -lna-runtime		\
+	-L$(top_builddir)/nautilus-actions/api		-lna-api		\
+	-L$(top_builddir)/nautilus-actions/runtime	-lna-runtime	\
 	$(NAUTILUS_ACTIONS_LIBS)									\
 	$(NULL)
 
diff --git a/nautilus-actions/utils/Makefile.am b/nautilus-actions/utils/Makefile.am
index 26a6620..5acfd41 100644
--- a/nautilus-actions/utils/Makefile.am
+++ b/nautilus-actions/utils/Makefile.am
@@ -32,6 +32,7 @@ bin_PROGRAMS = \
 	$(NULL)
 
 AM_CPPFLAGS += \
+	-I $(top_srcdir)											\
 	-I $(top_srcdir)/nautilus-actions							\
 	-DGNOMELOCALEDIR=\""$(datadir)/locale"\"					\
 	-DG_LOG_DOMAIN=\"${NA_LOGDOMAIN_UTILS}\"					\
@@ -46,7 +47,8 @@ nautilus_actions_new_SOURCES = \
 
 nautilus_actions_new_LDADD = \
 	$(top_builddir)/nautilus-actions/common/libna-common.la		\
-	-L$(top_builddir)/nautilus-actions/runtime -lna-runtime		\
+	-L$(top_builddir)/nautilus-actions/api		-lna-api		\
+	-L$(top_builddir)/nautilus-actions/runtime	-lna-runtime	\
 	$(NAUTILUS_ACTIONS_LIBS)									\
 	$(NULL)
 
@@ -58,6 +60,7 @@ nautilus_actions_schemas_SOURCES = \
 
 nautilus_actions_schemas_LDADD = \
 	$(top_builddir)/nautilus-actions/common/libna-common.la		\
-	-L$(top_builddir)/nautilus-actions/runtime -lna-runtime		\
+	-L$(top_builddir)/nautilus-actions/api		-lna-api		\
+	-L$(top_builddir)/nautilus-actions/runtime	-lna-runtime	\
 	$(NAUTILUS_ACTIONS_LIBS)									\
 	$(NULL)
diff --git a/nautilus-actions/utils/nautilus-actions-new.c b/nautilus-actions/utils/nautilus-actions-new.c
index 63c05a8..cb2484d 100644
--- a/nautilus-actions/utils/nautilus-actions-new.c
+++ b/nautilus-actions/utils/nautilus-actions-new.c
@@ -36,8 +36,10 @@
 #include <glib/gi18n.h>
 #include <stdlib.h>
 
+#include <api/na-iio-provider.h>
+
+#include <runtime/na-io-provider.h>
 #include <runtime/na-gconf-provider.h>
-#include <runtime/na-iio-provider.h>
 
 #include <common/na-iprefs.h>
 #include <common/na-object-api.h>
@@ -369,18 +371,12 @@ write_to_gconf( NAObjectAction *action, GSList **msg )
 {
 	NAGConfProvider *gconf;
 	guint ret;
-	gchar *str;
 
 	gconf = na_gconf_provider_new( NULL );
 
 	na_object_set_provider( action, NA_IIO_PROVIDER( gconf ));
 
-	str = NULL;
-	ret = na_iio_provider_write_item( NULL, NA_OBJECT( action ), &str );
-	if( str ){
-		*msg = g_slist_append( *msg, str );
-		g_free( str );
-	}
+	ret = na_io_provider_write_item( NULL, NA_OBJECT_ITEM( action ), msg );
 
 	return( ret == NA_IIO_PROVIDER_WRITE_OK );
 }