cssvalue: Don't crash when printing NULL strings

A NULL string should be printed as "none".

diff --git a/gtk/gtkcssstringvalue.c b/gtk/gtkcssstringvalue.c
index 9edda646c9cfd04fdec21b34ebdaf5f89d746d45..02405f4106f1cf1f23b64df25ae3bca230d6e709 100644 (file)
--- a/gtk/gtkcssstringvalue.c
+++ b/gtk/gtkcssstringvalue.c
@@ -65,6 +65,12 @@ gtk_css_value_string_print (const GtkCssValue *value,
   char *string = value->string;
   gsize len;
 
+  if (string == NULL)
+    {
+      g_string_append (str, "none");
+      return;
+    }
+
   g_string_append_c (str, '"');
 
   do {