measure_disk_usage: skip progress on NULL callback

In the real_..._async wrapper for GFile.measure_disk_usage, skip the
wrapping of the progress callback in the case that the user gave a NULL
callback to the async function.  This is a performance improvement
because the sync version won't have to do continuous sampling of the
clock to issue a call to the wrapper which will then do nothing.

Unfortunately, I made this simplifying assumption when writing the
wrapper, but forgot to actually implement it when making the sync call.
As a result, the wrapper is still called, and invokes the NULL callback,
causing a segfault.

Make sure we pass NULL if the user's callback was NULL.

https://bugzilla.gnome.org/show_bug.cgi?id=707787

diff --git a/gio/gfile.c b/gio/gfile.c
index 0c95942..d321c24 100644 (file)
--- a/gio/gfile.c
+++ b/gio/gfile.c
@@ -7453,7 +7453,7 @@ measure_disk_usage_thread (GTask        *task,
   MeasureResult result;
 
   if (g_file_measure_disk_usage (source_object, data->flags, cancellable,
-                                 measure_disk_usage_progress, task,
+                                 data->progress_callback ? measure_disk_usage_progress : NULL, task,
                                  &result.disk_usage, &result.num_dirs, &result.num_files,
                                  &error))
     g_task_return_pointer (task, g_memdup (&result, sizeof result), g_free);