[libgda] set: fix holder-attr-changed signal

[Daniel Espinosa Ortiz <despinosa src gnome org>]

commit 923ff9c2871dbd7810bc379b03c2708b147da3e1
Author: Daniel Espinosa Ortiz <esodan gmail com>
Date:   Sun Feb 17 19:59:43 2019 -0600

    set: fix holder-attr-changed signal

 libgda/gda-set.c | 43 +++++++++++++++++++++----------------------
 1 file changed, 21 insertions(+), 22 deletions(-)
---
diff --git a/libgda/gda-set.c b/libgda/gda-set.c
index aba0ec8f1..3146f4e76 100644
--- a/libgda/gda-set.c
+++ b/libgda/gda-set.c
@@ -695,15 +695,21 @@ gda_set_set_property (GObject *object,
 
        switch (param_id) {
        case PROP_ID:
-               g_free (priv->id);
+               if (priv->id != NULL)  {
+                       g_free (priv->id);
+               }
                priv->id = g_value_dup_string (value);
                break;
        case PROP_NAME:
-               g_free (priv->name);
+               if (priv->name != NULL) {
+                       g_free (priv->name);
+               }
                priv->name = g_value_dup_string (value);
                break;
        case PROP_DESCR:
-               g_free (priv->descr);
+               if (priv->descr) {
+                       g_free (priv->descr);
+               }
                priv->descr = g_value_dup_string (value);
                break;
        case PROP_HOLDERS: {
@@ -711,7 +717,7 @@ gda_set_set_property (GObject *object,
                GSList* holders;
                for (holders = (GSList*) g_value_get_pointer (value); holders; holders = holders->next) 
                        gda_set_real_add_holder (set, GDA_HOLDER (holders->data));
-               compute_public_data (set);      
+               compute_public_data (set);
                break;
        }
        case PROP_VALIDATE_CHANGES:
@@ -1870,26 +1876,24 @@ holder_notify_cb (GdaHolder *holder, GParamSpec *pspec, GdaSet *dataset)
        GType gtype;
        gtype = gda_holder_get_g_type (holder);
        if (!strcmp (pspec->name, "g-type")) {
-               g_assert (gtype != GDA_TYPE_NULL);
+               if (gtype == GDA_TYPE_NULL) {
+                       return;
+               }
                g_signal_emit (dataset, gda_set_signals[HOLDER_TYPE_SET], 0, holder);
        }
        else if (!strcmp (pspec->name, "name")) {
-               gchar *name = NULL;
-               g_object_get (dataset, "name", &name, NULL);
+               GValue *name = gda_value_new (G_TYPE_STRING);
+               g_object_get_property (dataset, "name", name);
                g_signal_emit (G_OBJECT (dataset), gda_set_signals[HOLDER_ATTR_CHANGED], 0, holder,
-                                    "name", name != NULL ? name : "NULL");
-               if (name != NULL) {
-                       g_free (name);
-               }
+                                    "name", name);
+               gda_value_free (name);
        }
        else if (!strcmp (pspec->name, "description")) {
-               gchar *desc = NULL;
-               g_object_get (dataset, "description", &desc, NULL);
+               GValue *desc = gda_value_new (G_TYPE_STRING);
+               g_object_get_property (dataset, "description", desc);
                g_signal_emit (G_OBJECT (dataset), gda_set_signals[HOLDER_ATTR_CHANGED], 0, holder,
                                     "description", desc);
-               if (desc != NULL) {
-                       g_free (desc);
-               }
+               gda_value_free (desc);
        }
 }
 
@@ -1931,12 +1935,7 @@ gda_set_real_add_holder (GdaSet *set, GdaHolder *holder)
                        g_signal_connect (G_OBJECT (holder), "source-changed",
                                          G_CALLBACK (source_changed_holder_cb), set);
                }
-               if (gda_holder_get_g_type (holder) == GDA_TYPE_NULL)
-                       g_signal_connect (G_OBJECT (holder), "notify::g-type",
-                                         G_CALLBACK (holder_notify_cb), set);
-               g_signal_connect (G_OBJECT (holder), "notify::name",
-                                 G_CALLBACK (holder_notify_cb), set);
-               g_signal_connect (G_OBJECT (holder), "notify::description",
+               g_signal_connect (G_OBJECT (holder), "notify",
                                  G_CALLBACK (holder_notify_cb), set);
                return TRUE;
        }