[gdk-pixbuf] Port gdk_pixbuf_new_from_stream_[at_scale_]async to GTask

[Matthias Clasen <matthiasc src gnome org>]

commit cd64cd3410f657d94608e78aeb6f211d0436cae9
Author: Debarshi Ray <debarshir gnome org>
Date:   Tue Nov 19 18:47:37 2013 +0100

    Port gdk_pixbuf_new_from_stream_[at_scale_]async to GTask
    
    https://bugzilla.gnome.org/show_bug.cgi?id=712704

 gdk-pixbuf/gdk-pixbuf-io.c |   54 +++++++++++++++++++++++--------------------
 1 files changed, 29 insertions(+), 25 deletions(-)
---
diff --git a/gdk-pixbuf/gdk-pixbuf-io.c b/gdk-pixbuf/gdk-pixbuf-io.c
index a98d125..f0cb99d 100644
--- a/gdk-pixbuf/gdk-pixbuf-io.c
+++ b/gdk-pixbuf/gdk-pixbuf-io.c
@@ -1553,29 +1553,28 @@ gdk_pixbuf_new_from_stream_at_scale (GInputStream  *stream,
 }
 
 static void
-new_from_stream_thread (GSimpleAsyncResult *result,
+new_from_stream_thread (GTask              *task,
                        GInputStream       *stream,
+                       AtScaleData        *data,
                        GCancellable       *cancellable)
 {
-       GdkPixbuf *pixbuf;
-       AtScaleData *data;
+       GdkPixbuf *pixbuf = NULL;
        GError *error = NULL;
 
        /* If data != NULL, we're scaling the pixbuf while loading it */
-       data = g_simple_async_result_get_op_res_gpointer (result);
        if (data != NULL)
                pixbuf = gdk_pixbuf_new_from_stream_at_scale (stream, data->width, data->height, 
data->preserve_aspect_ratio, cancellable, &error);
        else
                pixbuf = gdk_pixbuf_new_from_stream (stream, cancellable, &error);
 
-       g_simple_async_result_set_op_res_gpointer (result, NULL, NULL);
-
        /* Set the new pixbuf as the result, or error out */
        if (pixbuf == NULL) {
-               g_simple_async_result_take_error (result, error);
+               g_task_return_error (task, error);
        } else {
-               g_simple_async_result_set_op_res_gpointer (result, g_object_ref (pixbuf), g_object_unref);
+               g_task_return_pointer (task, g_object_ref (pixbuf), g_object_unref);
        }
+
+        g_clear_object (&pixbuf);
 }
 
 /**
@@ -1607,7 +1606,7 @@ gdk_pixbuf_new_from_stream_at_scale_async (GInputStream        *stream,
                                           GAsyncReadyCallback  callback,
                                           gpointer             user_data)
 {
-       GSimpleAsyncResult *result;
+       GTask *task;
        AtScaleData *data;
 
        g_return_if_fail (G_IS_INPUT_STREAM (stream));
@@ -1619,10 +1618,11 @@ gdk_pixbuf_new_from_stream_at_scale_async (GInputStream        *stream,
        data->height = height;
        data->preserve_aspect_ratio = preserve_aspect_ratio;
 
-       result = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, 
gdk_pixbuf_new_from_stream_at_scale_async);
-       g_simple_async_result_set_op_res_gpointer (result, data, (GDestroyNotify) 
at_scale_data_async_data_free);
-       g_simple_async_result_run_in_thread (result, (GSimpleAsyncThreadFunc) new_from_stream_thread, 
G_PRIORITY_DEFAULT, cancellable);
-       g_object_unref (result);
+       task = g_task_new (stream, cancellable, callback, user_data);
+       g_task_set_source_tag (task, gdk_pixbuf_new_from_stream_at_scale_async);
+       g_task_set_task_data (task, data, (GDestroyNotify) at_scale_data_async_data_free);
+       g_task_run_in_thread (task, (GTaskThreadFunc) new_from_stream_thread);
+       g_object_unref (task);
 }
 
 /**
@@ -1807,15 +1807,16 @@ gdk_pixbuf_new_from_stream_async (GInputStream        *stream,
                                  GAsyncReadyCallback  callback,
                                  gpointer             user_data)
 {
-       GSimpleAsyncResult *result;
+       GTask *task;
 
        g_return_if_fail (G_IS_INPUT_STREAM (stream));
        g_return_if_fail (callback != NULL);
        g_return_if_fail (!cancellable || G_IS_CANCELLABLE (cancellable));
 
-       result = g_simple_async_result_new (G_OBJECT (stream), callback, user_data, 
gdk_pixbuf_new_from_stream_async);
-       g_simple_async_result_run_in_thread (result, (GSimpleAsyncThreadFunc) new_from_stream_thread, 
G_PRIORITY_DEFAULT, cancellable);
-       g_object_unref (result);
+       task = g_task_new (stream, cancellable, callback, user_data);
+       g_task_set_source_tag (task, gdk_pixbuf_new_from_stream_async);
+       g_task_run_in_thread (task, (GTaskThreadFunc) new_from_stream_thread);
+       g_object_unref (task);
 }
 
 /**
@@ -1835,17 +1836,20 @@ GdkPixbuf *
 gdk_pixbuf_new_from_stream_finish (GAsyncResult  *async_result,
                                   GError       **error)
 {
-       GSimpleAsyncResult *result = G_SIMPLE_ASYNC_RESULT (async_result);
+       GTask *task;
 
-       g_return_val_if_fail (G_IS_ASYNC_RESULT (async_result), NULL);
-       g_return_val_if_fail (!error || (error && !*error), NULL);
-       g_warn_if_fail (g_simple_async_result_get_source_tag (result) == gdk_pixbuf_new_from_stream_async ||
-                       g_simple_async_result_get_source_tag (result) == 
gdk_pixbuf_new_from_stream_at_scale_async);
+       /* Can not use g_task_is_valid because our GTask has a
+        * source_object which is not available to us anymore.
+        */
+       g_return_val_if_fail (G_IS_TASK (async_result), NULL);
 
-       if (g_simple_async_result_propagate_error (result, error))
-               return NULL;
+       task = G_TASK (async_result);
+
+       g_return_val_if_fail (!error || (error && !*error), NULL);
+       g_warn_if_fail (g_task_get_source_tag (task) == gdk_pixbuf_new_from_stream_async ||
+                       g_task_get_source_tag (task) == gdk_pixbuf_new_from_stream_at_scale_async);
 
-       return g_simple_async_result_get_op_res_gpointer (result);
+       return g_task_propagate_pointer (task, error);
 }
 
 static void