From 77aad430ef77b89835c8e04995b11fabeed044fb Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?P=C5=99emysl=20Janouch?= <p.janouch@gmail.com>
Date: Wed, 29 Aug 2012 21:56:59 +0200
Subject: [PATCH] Add `changed' signals to LdCategory.

---
 liblogdiag/ld-category.c | 32 ++++++++++++++++++++++++++++++++
 liblogdiag/ld-category.h |  7 +++----
 liblogdiag/ld-library.c  | 10 ++++++++++
 3 files changed, 45 insertions(+), 4 deletions(-)

diff --git a/liblogdiag/ld-category.c b/liblogdiag/ld-category.c
index e7b212d..6a4cf8c 100644
--- a/liblogdiag/ld-category.c
+++ b/liblogdiag/ld-category.c
@@ -85,6 +85,26 @@ ld_category_class_init (LdCategoryClass *klass)
 		"", G_PARAM_READWRITE);
 	g_object_class_install_property (object_class, PROP_HUMAN_NAME, pspec);
 
+/**
+ * LdCategory::symbols-changed:
+ *
+ * The list of symbols has changed.
+ */
+	klass->symbols_changed_signal = g_signal_new
+		("symbols-changed", G_TYPE_FROM_CLASS (klass),
+		G_SIGNAL_RUN_LAST, 0, NULL, NULL,
+		g_cclosure_marshal_VOID__VOID, G_TYPE_NONE, 0);
+
+/**
+ * LdCategory::children-changed:
+ *
+ * The list of subcategory children has changed.
+ */
+	klass->children_changed_signal = g_signal_new
+		("children-changed", G_TYPE_FROM_CLASS (klass),
+		G_SIGNAL_RUN_LAST, 0, NULL, NULL,
+		g_cclosure_marshal_VOID__VOID, G_TYPE_NONE, 0);
+
 	g_type_class_add_private (klass, sizeof (LdCategoryPrivate));
 }
 
@@ -285,6 +305,9 @@ ld_category_insert_symbol (LdCategory *self, LdSymbol *symbol, gint pos)
 
 	self->priv->symbols = g_slist_insert (self->priv->symbols, symbol, pos);
 	g_object_ref (symbol);
+
+	g_signal_emit (self,
+		LD_CATEGORY_GET_CLASS (self)->symbols_changed_signal, 0);
 	return TRUE;
 }
 
@@ -307,6 +330,9 @@ ld_category_remove_symbol (LdCategory *self, LdSymbol *symbol)
 	{
 		self->priv->symbols = g_slist_delete_link (self->priv->symbols, link);
 		g_object_unref (symbol);
+
+		g_signal_emit (self,
+			LD_CATEGORY_GET_CLASS (self)->symbols_changed_signal, 0);
 	}
 }
 
@@ -379,6 +405,9 @@ ld_category_add_child (LdCategory *self, LdCategory *category)
 	self->priv->subcategories = g_slist_insert_before
 		(self->priv->subcategories, iter, category);
 	g_object_ref (category);
+
+	g_signal_emit (self,
+		LD_CATEGORY_GET_CLASS (self)->children_changed_signal, 0);
 	return TRUE;
 }
 
@@ -404,6 +433,9 @@ ld_category_remove_child (LdCategory *self, LdCategory *category)
 		self->priv->subcategories
 			= g_slist_delete_link (self->priv->subcategories, link);
 		g_object_unref (category);
+
+		g_signal_emit (self,
+			LD_CATEGORY_GET_CLASS (self)->children_changed_signal, 0);
 	}
 }
 
diff --git a/liblogdiag/ld-category.h b/liblogdiag/ld-category.h
index 5bbb00f..6b77596 100644
--- a/liblogdiag/ld-category.h
+++ b/liblogdiag/ld-category.h
@@ -41,14 +41,13 @@ struct _LdCategory
 	LdCategoryPrivate *priv;
 };
 
-/* TODO: If required sometime, categories (and maybe symbols) should implement
- *       a "changed" signal. This can be somewhat tricky. The library might be
- *       a good candidate for what they call a proxy. See GtkUIManager.
- */
 struct _LdCategoryClass
 {
 /*< private >*/
 	GObjectClass parent_class;
+
+	guint symbols_changed_signal;
+	guint children_changed_signal;
 };
 
 
diff --git a/liblogdiag/ld-library.c b/liblogdiag/ld-library.c
index 2b4c704..75e377c 100644
--- a/liblogdiag/ld-library.c
+++ b/liblogdiag/ld-library.c
@@ -328,6 +328,16 @@ ld_library_load (LdLibrary *self, const gchar *directory)
 	data.changed = FALSE;
 	foreach_dir (directory, load_category_cb, &data, NULL);
 
+	/* XXX: It might also make sense to just forward the "children-changed"
+	 *      signal of the root category but we'd have to block it here anyway,
+	 *      so that we don't unnecessarily fire events for every single change.
+	 *
+	 *      The user code isn't supposed to make changes to / and it's its own
+	 *      problem if it keeps reloading something a hundred times in a row.
+	 *
+	 *      That said, it'd be possible to add change grouping methods to
+	 *      LdCategory and so delay the signal emission until an `unblock'.
+	 */
 	if (data.changed)
 		g_signal_emit (self, LD_LIBRARY_GET_CLASS (self)->changed_signal, 0);