1 files changed, 128 insertions, 0 deletions
diff --git a/liblogdiag/ld-undo-action.c b/liblogdiag/ld-undo-action.c
new file mode 100644
index 0000000..924a03e
--- /dev/null
+++ b/liblogdiag/ld-undo-action.c
@@ -0,0 +1,128 @@
+/*
+ * ld-undo-action.c
+ *
+ * This file is a part of logdiag.
+ * Copyright Přemysl Janouch 2011. All rights reserved.
+ *
+ * See the file LICENSE for licensing information.
+ *
+ */
+
+#include <string.h>
+
+#include "liblogdiag.h"
+#include "config.h"
+
+
+/**
+ * SECTION:ld-undo-action
+ * @short_description: An action that can be undone.
+ * @see_also: #LdDiagram, #LdDiagramObject
+ *
+ * #LdUndoAction represents an action that can be reverted.
+ */
+
+/*
+ * LdUndoActionPrivate:
+ * @undo_func: a callback to undo the action.
+ * @redo_func: a callback to redo the action.
+ * @destroy_func: a callback to destroy user data.
+ * @user_data: data given by the user.
+ */
+struct _LdUndoActionPrivate
+{
+	LdUndoActionFunc undo_func;
+	LdUndoActionFunc redo_func;
+	LdUndoActionFunc destroy_func;
+	gpointer user_data;
+};
+
+static void ld_undo_action_finalize (GObject *gobject);
+
+
+G_DEFINE_TYPE (LdUndoAction, ld_undo_action, G_TYPE_OBJECT);
+
+static void
+ld_undo_action_class_init (LdUndoActionClass *klass)
+{
+	GObjectClass *object_class;
+
+	object_class = G_OBJECT_CLASS (klass);
+	object_class->finalize = ld_undo_action_finalize;
+
+	g_type_class_add_private (klass, sizeof (LdUndoActionPrivate));
+}
+
+static void
+ld_undo_action_init (LdUndoAction *self)
+{
+	self->priv = G_TYPE_INSTANCE_GET_PRIVATE
+		(self, LD_TYPE_UNDO_ACTION, LdUndoActionPrivate);
+}
+
+static void
+ld_undo_action_finalize (GObject *gobject)
+{
+	LdUndoAction *self;
+
+	self = LD_UNDO_ACTION (gobject);
+	if (self->priv->destroy_func)
+		self->priv->destroy_func (self->priv->user_data);
+
+	/* Chain up to the parent class. */
+	G_OBJECT_CLASS (ld_undo_action_parent_class)->finalize (gobject);
+}
+
+
+/**
+ * ld_undo_action_new:
+ * @undo_func: a callback to undo the action.
+ * @redo_func: a callback to redo the action.
+ * @destroy_func: (allow-none): a callback to destroy user data.
+ * @user_data: user data passed to callbacks.
+ *
+ * Return value: a new #LdUndoAction object.
+ */
+LdUndoAction *
+ld_undo_action_new (LdUndoActionFunc undo_func,
+	LdUndoActionFunc redo_func, LdUndoActionFunc destroy_func,
+	gpointer user_data)
+{
+	LdUndoAction *self;
+
+	g_return_val_if_fail (undo_func != NULL, NULL);
+	g_return_val_if_fail (redo_func != NULL, NULL);
+
+	self = g_object_new (LD_TYPE_UNDO_ACTION, NULL);
+	self->priv->undo_func = undo_func;
+	self->priv->redo_func = redo_func;
+	self->priv->destroy_func = destroy_func;
+	self->priv->user_data = user_data;
+	return self;
+}
+
+/**
+ * ld_undo_action_undo:
+ * @self: an #LdUndoAction object.
+ *
+ * Undo the action handled by this object.
+ */
+void
+ld_undo_action_undo (LdUndoAction *self)
+{
+	g_return_if_fail (LD_IS_UNDO_ACTION (self));
+	self->priv->undo_func (self->priv->user_data);
+}
+
+/**
+ * ld_undo_action_redo:
+ * @self: an #LdUndoAction object.
+ *
+ * Redo the action handled by this object.
+ */
+void
+ld_undo_action_redo (LdUndoAction *self)
+{
+	g_return_if_fail (LD_IS_UNDO_ACTION (self));
+	self->priv->redo_func (self->priv->user_data);
+}