new class for config database access and monitoring.

2002-08-16  Rodrigo Moya <rodrigo@ximian.com>

	* e-config-listener.[ch]: new class for config database access and
	monitoring.

	* Makefile.am: added new files.

svn path=/trunk/; revision=17816

4 files changed, 375 insertions, 0 deletions

diff --git a/e-util/ChangeLog b/e-util/ChangeLog
index bac53db150..26e78fb47f 100644
--- a/e-util/ChangeLog
+++ b/e-util/ChangeLog
@@ -1,3 +1,10 @@
+2002-08-16  Rodrigo Moya <rodrigo@ximian.com>
+
+	* e-config-listener.[ch]: new class for config database access and
+	monitoring.
+
+	* Makefile.am: added new files.
+
 2002-08-14  Rodrigo Moya <rodrigo@ximian.com>
 
 	* e-component-listener.[ch]: new class for controlling a component,
diff --git a/e-util/Makefile.am b/e-util/Makefile.am
index f2283b3a0f..75481cdfcf 100644
--- a/e-util/Makefile.am
+++ b/e-util/Makefile.am
@@ -23,6 +23,7 @@ eutilinclude_HEADERS = 				\
 	e-categories-master-list-wombat.h	\
 	e-categories-config.h			\
 	e-component-listener.h			\
+	e-config-listener.h			\
 	e-corba-utils.h				\
 	e-dialog-utils.h			\
 	e-dialog-widgets.h			\
@@ -51,6 +52,7 @@ libeutil_la_SOURCES =				\
 	e-categories-master-list-wombat.c	\
 	e-categories-config.c			\
 	e-component-listener.c			\
+	e-config-listener.c			\
 	e-corba-utils.c				\
 	e-dialog-utils.c			\
 	e-dialog-widgets.c			\
diff --git a/e-util/e-config-listener.c b/e-util/e-config-listener.c
new file mode 100644
index 0000000000..e6fd8dbb9c
--- /dev/null
+++ b/e-util/e-config-listener.c
@@ -0,0 +1,313 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
+/*
+ * Configuration component listener
+ *
+ * Author:
+ *   Rodrigo Moya <rodrigo@ximian.com>
+ *
+ * Copyright 2002, Ximian, Inc.
+ */
+
+#include <gtk/gtktypeutils.h>
+#include <bonobo/bonobo-exception.h>
+#include <bonobo/bonobo-event-source.h>
+#include <bonobo/bonobo-moniker-util.h>
+#include <bonobo/bonobo-object.h>
+#include "e-config-listener.h"
+
+#define PARENT_TYPE GTK_TYPE_OBJECT
+
+typedef struct {
+	EConfigListener *cl;
+	char *key;
+	GtkFundamentalType type;
+	union {
+		char *v_str;
+		gboolean v_bool;
+	} value;
+	gboolean used_default;
+} KeyData;
+
+struct _EConfigListenerPrivate {
+	Bonobo_ConfigDatabase db;
+	GHashTable *keys;
+};
+
+static void e_config_listener_class_init (EConfigListenerClass *klass);
+static void e_config_listener_init       (EConfigListener *cl);
+static void e_config_listener_destroy    (GtkObject *object);
+
+static GtkObjectClass *parent_class = NULL;
+
+static void
+e_config_listener_class_init (EConfigListenerClass *klass)
+{
+	GtkObjectClass *object_class = GTK_OBJECT_CLASS (klass);
+
+	parent_class = gtk_type_class (PARENT_TYPE);
+
+	object_class->destroy = e_config_listener_destroy;
+}
+
+static void
+e_config_listener_init (EConfigListener *cl)
+{
+	CORBA_Environment ev;
+
+	/* allocate internal structure */
+	cl->priv = g_new0 (EConfigListenerPrivate, 1);
+
+	cl->priv->keys = g_hash_table_new (g_str_hash, g_str_equal);
+
+	/* activate the configuration database */
+	CORBA_exception_init (&ev);
+	cl->priv->db = bonobo_get_object ("wombat:", "Bonobo/ConfigDatabase", &ev);
+
+	if (BONOBO_EX (&ev) || cl->priv->db == CORBA_OBJECT_NIL) {
+		CORBA_exception_free (&ev);
+		cl->priv->db = CORBA_OBJECT_NIL;
+	}
+}
+
+static void
+free_key_hash (gpointer key, gpointer value, gpointer user_data)
+{
+	KeyData *kd = (KeyData *) value;
+
+	g_return_if_fail (kd != NULL);
+
+	g_free (kd->key);
+	switch (kd->type) {
+	case GTK_TYPE_STRING :
+		g_free (kd->value.v_str);
+		break;
+	default :
+	}
+
+	g_free (kd);
+}
+
+static void
+e_config_listener_destroy (GtkObject *object)
+{
+	EConfigListener *cl = (EConfigListener *) object;
+
+	g_return_if_fail (E_IS_CONFIG_LISTENER (cl));
+
+	if (cl->priv->db != CORBA_OBJECT_NIL) {
+		bonobo_object_release_unref (cl->priv->db, NULL);
+		cl->priv->db = CORBA_OBJECT_NIL;
+	}
+
+	g_hash_table_foreach (cl->priv->keys, (GHFunc) free_key_hash, NULL);
+	g_hash_table_destroy (cl->priv->keys);
+	cl->priv->keys = NULL;
+
+	g_free (cl->priv);
+	cl->priv = NULL;
+
+	if (GTK_OBJECT_CLASS (parent_class)->destroy)
+		(* GTK_OBJECT_CLASS (parent_class)->destroy) (object);
+}
+
+GtkType
+e_config_listener_get_type (void)
+{
+	static GtkType type = 0;
+
+	if (!type) {
+		static const GtkTypeInfo info = {
+			"EConfigListener",
+			sizeof (EConfigListener),
+			sizeof (EConfigListenerClass),
+			(GtkClassInitFunc) e_config_listener_class_init,
+			(GtkObjectInitFunc) e_config_listener_init,
+			NULL, /* reserved_1 */
+			NULL, /* reserved_2 */
+			(GtkClassInitFunc) NULL
+		};
+
+		type = gtk_type_unique (PARENT_TYPE, &info);
+	}
+
+	return type;
+}
+
+/**
+ * e_config_listener_new
+ *
+ * Create a new configuration listener, which is an object which
+ * allows to listen for changes in the configuration database. It keeps
+ * an updated copy of all requested configuration entries, so that
+ * access is much quicker and instantaneous.
+ *
+ * Returns: the newly created listener.
+ */
+EConfigListener *
+e_config_listener_new (void)
+{
+	EConfigListener *cl;
+
+	cl = gtk_type_new (E_CONFIG_LISTENER_TYPE);
+	return cl;
+}
+
+static void
+property_change_cb (BonoboListener *listener,
+		    char *event_name,
+		    CORBA_any *any,
+		    CORBA_Environment *ev,
+		    gpointer user_data)
+{
+	KeyData *kd = (KeyData *) user_data;
+
+	g_return_if_fail (any != NULL);
+	g_return_if_fail (kd != NULL);
+
+	/* free previous value */
+	if (kd->type == GTK_TYPE_STRING)
+		g_free (kd->value.v_str);
+
+	/* set new value */
+	if (bonobo_arg_type_is_equal (any->_type, BONOBO_ARG_BOOLEAN, NULL)) {
+		kd->type = GTK_TYPE_BOOL;
+		kd->value.v_bool = BONOBO_ARG_GET_BOOLEAN (any);
+	} else if (bonobo_arg_type_is_equal (any->_type, BONOBO_ARG_STRING, NULL)) {
+		kd->type = GTK_TYPE_STRING;
+		kd->value.v_str = g_strdup (BONOBO_ARG_GET_STRING (any));
+	} else
+		return;
+}
+
+static KeyData *
+add_key (EConfigListener *cl, const char *key, GtkFundamentalType type,
+	 gpointer value, gboolean used_default)
+{
+	KeyData *kd;
+	char *event_name;
+	CORBA_Environment ev;
+
+	/* add the key to our hash table */
+	kd = g_new0 (KeyData, 1);
+	kd->cl = cl;
+	kd->key = g_strdup (key);
+	kd->type = type;
+	switch (type) {
+	case GTK_TYPE_BOOL :
+		memcpy (&kd->value.v_bool, value, sizeof (gboolean));
+		break;
+	case GTK_TYPE_STRING :
+		kd->value.v_str = (char *) value;
+		break;
+	default :
+	}
+
+	kd->used_default = used_default;
+
+	/* add the listener for changes */
+	event_name = g_strdup_printf ("=Bonobo/ConfigDatabase:change%s",
+				      kd->key);
+
+	CORBA_exception_init (&ev);
+	bonobo_event_source_client_add_listener (
+		cl->priv->db,
+		property_change_cb,
+		event_name,
+		&ev, kd);
+	if (BONOBO_EX (&ev)) {
+		CORBA_exception_free (&ev);
+		free_key_hash (kd->key, kd, NULL);
+		return NULL;
+	}
+
+	g_hash_table_insert (cl->priv->keys, kd->key, kd);
+
+	CORBA_exception_free (&ev);
+	g_free (event_name);
+
+	return kd;
+}
+
+char *
+e_config_listener_get_string_with_default (EConfigListener *cl,
+					   const char *key,
+					   const char *def,
+					   gboolean *used_default)
+{
+	char *str;
+	KeyData *kd;
+	gboolean d;
+	gpointer orig_key, orig_value;
+
+	g_return_val_if_fail (E_IS_CONFIG_LISTENER (cl), NULL);
+	g_return_val_if_fail (key != NULL, NULL);
+
+	/* search for the key in our hash table */
+	if (!g_hash_table_lookup_extended (cl->priv->keys, key, &orig_key, &orig_value)) {
+		/* not found, so retrieve it from the configuration database */
+		str = bonobo_config_get_string_with_default (cl->priv->db, key, (char *) def, &d);
+		if (str) {
+			kd = add_key (cl, key, GTK_TYPE_STRING, (gpointer) str, d);
+
+			if (used_default != NULL)
+				*used_default = d;
+		} else
+			return NULL;
+	} else {
+		kd = (KeyData *) orig_value;
+		g_assert (kd != NULL);
+
+		if (kd->type == GTK_TYPE_STRING) {
+			str = g_strdup (kd->value.v_str);
+			if (used_default != NULL)
+				*used_default = kd->used_default;
+		} else
+			return NULL;
+	}
+
+	return str;
+}
+
+gboolean
+e_config_listener_get_boolean_with_default (EConfigListener *cl,
+					    const char *key,
+					    gboolean def,
+					    gboolean *used_default)
+{
+	gboolean value;
+	KeyData *kd;
+	gboolean d;
+	gpointer orig_key, orig_value;
+
+	g_return_val_if_fail (E_IS_CONFIG_LISTENER (cl), FALSE);
+	g_return_val_if_fail (key != NULL, FALSE);
+
+	/* search for the key in our hash table */
+	if (!g_hash_table_lookup_extended (cl->priv->keys, key, &orig_key, &orig_value)) {
+		/* not found, so retrieve it from the configuration database */
+		value = bonobo_config_get_boolean_with_default (cl->priv->db, key, def, &d);
+		kd = add_key (cl, key, GTK_TYPE_BOOL, &value, d);
+
+		if (used_default != NULL)
+			*used_default = d;
+	} else {
+		kd = (KeyData *) orig_value;
+		g_assert (kd != NULL);
+
+		if (kd->type == GTK_TYPE_BOOL) {
+			value = kd->value.v_bool;
+			if (used_default != NULL)
+				*used_default = kd->used_default;
+		} else
+			return FALSE;
+	}
+
+	return value;
+}
+
+Bonobo_ConfigDatabase
+e_config_listener_get_db (EConfigListener *cl)
+{
+	g_return_val_if_fail (E_IS_CONFIG_LISTENER (cl), CORBA_OBJECT_NIL);
+	return cl->priv->db;
+}
diff --git a/e-util/e-config-listener.h b/e-util/e-config-listener.h
new file mode 100644
index 0000000000..b83565d85f
--- /dev/null
+++ b/e-util/e-config-listener.h
@@ -0,0 +1,53 @@
+/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
+/*
+ * Configuration component listener
+ *
+ * Author:
+ *   Rodrigo Moya <rodrigo@ximian.com>
+ *
+ * Copyright 2002, Ximian, Inc.
+ */
+
+#ifndef __E_CONFIG_LISTENER_H__
+#define __E_CONFIG_LISTENER_H__
+
+#include <gtk/gtkobject.h>
+#include <libgnome/gnome-defs.h>
+#include <bonobo-conf/bonobo-config-database.h>
+
+BEGIN_GNOME_DECLS
+
+#define E_CONFIG_LISTENER_TYPE        (e_config_listener_get_type ())
+#define E_CONFIG_LISTENER(o)          (GTK_CHECK_CAST ((o), E_CONFIG_LISTENER_TYPE, EConfigListener))
+#define E_CONFIG_LISTENER_CLASS(k)    (GTK_CHECK_CLASS_CAST((k), E_CONFIG_LISTENER_TYPE, EConfigListenerClass))
+#define E_IS_CONFIG_LISTENER(o)       (GTK_CHECK_TYPE ((o), E_CONFIG_LISTENER_TYPE))
+#define E_IS_CONFIG_LISTENER_CLASS(k) (GTK_CHECK_CLASS_TYPE ((k), E_CONFIG_LISTENER_TYPE))
+
+typedef struct _EConfigListenerPrivate EConfigListenerPrivate;
+
+typedef struct {
+	GtkObject object;
+	EConfigListenerPrivate *priv;
+} EConfigListener;
+
+typedef struct {
+	GtkObjectClass parent_class;
+} EConfigListenerClass;
+
+GtkType               e_config_listener_get_type (void);
+EConfigListener      *e_config_listener_new (void);
+
+char                 *e_config_listener_get_string_with_default (EConfigListener *cl,
+								 const char *key,
+								 const char *def,
+								 gboolean *used_default);
+gboolean              e_config_listener_get_boolean_with_default (EConfigListener *cl,
+								  const char *key,
+								  gboolean def,
+								  gboolean *used_default);
+
+Bonobo_ConfigDatabase e_config_listener_get_db (EConfigListener *cl);
+
+END_GNOME_DECLS
+
+#endif