add comment, remove _

gst/cgo_exports.go

@@ -245,14 +245,14 @@ func goGlobalPluginInit(plugin *C.GstPlugin) C.gboolean {
 
 //export goLogFunction
 func goLogFunction(
-	_ *C.GstDebugCategory,
+	category *C.GstDebugCategory,
 	level C.GstDebugLevel,
 	file *C.gchar,
 	function *C.gchar,
 	line C.gint,
 	object *C.GObject,
 	message *C.GstDebugMessage,
-	_ C.gpointer,
+	userData C.gpointer,
 ) {
 	logFnMu.RLock()
 	f := customLogFunction

gst/gst_debug.go

@@ -203,6 +203,8 @@ var (
 	customLogFunction LogFunction
 )
 
+// SetLogFunction is used to replace gstreamer's default logging function.
+// Setting to nil will revert to the default logging function.
 func SetLogFunction(f LogFunction) {
 	logFnMu.Lock()
 	defer logFnMu.Unlock()