commit 542c9e333748831b6f3cb4a18b0e9c81b14c41bf
Author: dequis <dx@dxzone.com.ar>
Date:   Mon Jun 13 01:41:01 2016 -0300

    instantbird: prefs: observe, callback stuff

diff --git a/libpurple/prefs.c b/libpurple/prefs.c
index 4e2de2b..9adf4ab 100644
--- a/libpurple/prefs.c
+++ b/libpurple/prefs.c
@@ -45,10 +45,13 @@ struct pref_cb {
 	gpointer data;
 	guint id;
 	void *handle;
+	void *observer;
+	char *name;
 };
 
 static guint       save_timer = 0;
 static gboolean    prefs_loaded = FALSE;
+static GSList     *callbacks = NULL;
 
 static gboolean
 save_cb(gpointer data)
@@ -158,15 +161,27 @@ purple_prefs_destroy()
 void
 purple_prefs_trigger_callback(const char *name)
 {
-	struct purple_pref *pref = find_pref(name);
-
-	if(!pref) {
-		purple_debug_error("prefs",
-				"purple_prefs_trigger_callback: Unknown pref %s\n", name);
-		return;
+	GSList *cbs;
+
+	purple_debug_misc("prefs", "trigger callback %s\n", name);
+
+	for (cbs = callbacks; cbs; cbs = cbs->next) {
+		const char *cb_name = ((struct pref_cb *)cbs->data)->name;
+		size_t len = strlen(cb_name);
+		if (!strncmp(cb_name, name, len) &&
+		    (name[len] == 0 || name[len] == '/' ||
+		     (len && name[len - 1] == '/'))) {
+			/* This test should behave like this:
+			 * name    = /toto/tata
+			 * cb_name = /toto/tata --> true
+			 * cb_name = /toto/tatatiti --> false
+			 * cb_name = / --> true
+			 * cb_name = /toto --> true
+			 * cb_name = /toto/ --> true
+			 */
+			purple_prefs_observe(cbs->data);
+		}
 	}
-
-	do_callbacks(name, pref);
 }
 
 void
@@ -334,18 +349,15 @@ purple_prefs_get_string(const char *name)
 guint
 purple_prefs_connect_callback(void *handle, const char *name, PurplePrefCallback func, gpointer data)
 {
-	struct purple_pref *pref;
 	struct pref_cb *cb;
 	static guint cb_id = 0;
+	PurplePrefsUiOps *uiop = NULL;
 
 	g_return_val_if_fail(name != NULL, 0);
 	g_return_val_if_fail(func != NULL, 0);
 
-	pref = find_pref(name);
-	if (pref == NULL) {
-		purple_debug_error("prefs", "purple_prefs_connect_callback: Unknown pref %s\n", name);
-		return 0;
-	}
+	uiop = purple_prefs_get_ui_ops();
+	g_return_val_if_fail(uiop, 0);
 
 	cb = g_new0(struct pref_cb, 1);
 
@@ -353,26 +365,92 @@ purple_prefs_connect_callback(void *handle, const char *name, PurplePrefCallback
 	cb->data = data;
 	cb->id = ++cb_id;
 	cb->handle = handle;
+	cb->name = g_strdup(name);
 
-	pref->callbacks = g_slist_append(pref->callbacks, cb);
+	cb->observer = uiop->add_observer(name, cb);
+
+	if (cb->observer == NULL) {
+		purple_debug_error("prefs", "purple_prefs_connect_callback: add observer failed for %s\n", name);
+		g_free(cb->name);
+		g_free(cb);
+		return 0;
+	}
 
+	callbacks = g_slist_append(callbacks, cb);
 	return cb->id;
 }
 
+void purple_prefs_observe(gpointer data)
+{
+	struct pref_cb *cb = data;
+	PurplePrefsUiOps *uiop = purple_prefs_get_ui_ops();
+	gconstpointer value = NULL;
+	PurplePrefType type = PURPLE_PREF_NONE;
+	type = uiop->get_type(cb->name);
+
+	purple_debug_misc("prefs", "observe name = %s\n", cb->name);
+
+	switch (type) {
+		case PURPLE_PREF_INT:
+			value = GINT_TO_POINTER(uiop->get_int(cb->name));
+			break;
+		case PURPLE_PREF_BOOLEAN:
+			value = GINT_TO_POINTER(uiop->get_bool(cb->name));
+			break;
+		case PURPLE_PREF_STRING:
+			value = uiop->get_string(cb->name);
+			break;
+		case PURPLE_PREF_NONE:
+			break;
+		default:
+			purple_debug_error("prefs", "Unexpected type = %i\n", type);
+	}
+	cb->func(cb->name, type, value, cb->data);
+}
 
 void
 purple_prefs_disconnect_callback(guint callback_id)
 {
-	disco_callback_helper(&prefs, callback_id);
-}
+	GSList *cbs;
 
+	for (cbs = callbacks; cbs; cbs = cbs->next) {
+		struct pref_cb *cb = cbs->data;
+		if (cb->id == callback_id) {
+			PurplePrefsUiOps *uiop = purple_prefs_get_ui_ops();
+			uiop->remove_observer(cb->name, cb->observer);
+
+			callbacks = g_slist_delete_link(callbacks, cbs);
+			g_free(cb->name);
+			g_free(cb);
+			return;
+		}
+	}
+}
 
 void
 purple_prefs_disconnect_by_handle(void *handle)
 {
+	GSList *cbs;
+
 	g_return_if_fail(handle != NULL);
 
-	disco_callback_helper_handle(&prefs, handle);
+	cbs = callbacks;
+	while (cbs != NULL) {
+		PurplePrefsUiOps *uiop;
+		struct pref_cb *cb = cbs->data;
+		if (cb->handle != handle) {
+			cbs = cbs->next;
+			continue;
+		}
+
+		uiop = purple_prefs_get_ui_ops();
+		uiop->remove_observer(cb->name, cb->observer);
+
+		callbacks = g_slist_delete_link(callbacks, cbs);
+		g_free(cb->name);
+		g_free(cb);
+		cbs = callbacks;
+	}
 }
 
 GList *