[gtk+/wip/otte/vulkan: 3/3] gskrenderer: Add GError argument to gsk_renderer_realize()

[Benjamin Otte <otte src gnome org>]

commit 1e77f69b0acf5ebdfcb602b2a18f7f5a08d4c8cf
Author: Benjamin Otte <otte redhat com>
Date:   Tue Nov 29 04:51:07 2016 +0100

    gskrenderer: Add GError argument to gsk_renderer_realize()
    
    This way, we don't spam criticals when GL is not available. Instead, we
    print a useful debug message to stderr and continue with the Cairo renderer.

 gsk/gskcairorenderer.c   |    5 ++-
 gsk/gskglrenderer.c      |   52 +++++++++++++++++++--------------------------
 gsk/gskrenderer.c        |   25 ++++++++++++++--------
 gsk/gskrenderer.h        |    3 +-
 gsk/gskrendererprivate.h |    3 +-
 5 files changed, 45 insertions(+), 43 deletions(-)
---
diff --git a/gsk/gskcairorenderer.c b/gsk/gskcairorenderer.c
index 9c9929c..4c9dfef 100644
--- a/gsk/gskcairorenderer.c
+++ b/gsk/gskcairorenderer.c
@@ -34,8 +34,9 @@ struct _GskCairoRendererClass
 G_DEFINE_TYPE (GskCairoRenderer, gsk_cairo_renderer, GSK_TYPE_RENDERER)
 
 static gboolean
-gsk_cairo_renderer_realize (GskRenderer *renderer,
-                            GdkWindow   *window)
+gsk_cairo_renderer_realize (GskRenderer  *renderer,
+                            GdkWindow    *window,
+                            GError      **error)
 {
   return TRUE;
 }
diff --git a/gsk/gskglrenderer.c b/gsk/gskglrenderer.c
index 1df501a..853f690 100644
--- a/gsk/gskglrenderer.c
+++ b/gsk/gskglrenderer.c
@@ -187,10 +187,11 @@ gsk_gl_renderer_destroy_buffers (GskGLRenderer *self)
 }
 
 static gboolean
-gsk_gl_renderer_create_programs (GskGLRenderer *self)
+gsk_gl_renderer_create_programs (GskGLRenderer  *self,
+                                 GError        **error)
 {
   GskShaderBuilder *builder;
-  GError *error = NULL;
+  GError *shader_error = NULL;
   gboolean res = FALSE;
 
   builder = gsk_shader_builder_new ();
@@ -241,21 +242,23 @@ gsk_gl_renderer_create_programs (GskGLRenderer *self)
 #endif
 
   self->blend_program_id =
-    gsk_shader_builder_create_program (builder, "blend.vs.glsl", "blend.fs.glsl", &error);
-  if (error != NULL)
+    gsk_shader_builder_create_program (builder, "blend.vs.glsl", "blend.fs.glsl", &shader_error);
+  if (shader_error != NULL)
     {
-      g_critical ("Unable to create 'blend' program: %s", error->message);
-      g_error_free (error);
+      g_propagate_prefixed_error (error,
+                                  shader_error,
+                                  "Unable to create 'blend' program: ");
       g_object_unref (builder);
       goto out;
     }
 
   self->blit_program_id =
-    gsk_shader_builder_create_program (builder, "blit.vs.glsl", "blit.fs.glsl", &error);
-  if (error != NULL)
+    gsk_shader_builder_create_program (builder, "blit.vs.glsl", "blit.fs.glsl", &shader_error);
+  if (shader_error != NULL)
     {
-      g_critical ("Unable to create 'blit' program: %s", error->message);
-      g_error_free (error);
+      g_propagate_prefixed_error (error,
+                                  shader_error,
+                                  "Unable to create 'blit' program: ");
       g_object_unref (builder);
       goto out;
     }
@@ -278,35 +281,24 @@ gsk_gl_renderer_destroy_programs (GskGLRenderer *self)
 }
 
 static gboolean
-gsk_gl_renderer_realize (GskRenderer *renderer,
-                         GdkWindow   *window)
+gsk_gl_renderer_realize (GskRenderer  *renderer,
+                         GdkWindow    *window,
+                         GError      **error)
 {
   GskGLRenderer *self = GSK_GL_RENDERER (renderer);
-  GError *error = NULL;
 
   /* If we didn't get a GdkGLContext before realization, try creating
    * one now, for our exclusive use.
    */
   if (self->gl_context == NULL)
     {
-      self->gl_context = gdk_window_create_gl_context (window, &error);
-      if (error != NULL)
-        {
-          g_critical ("Unable to create GL context for renderer: %s",
-                      error->message);
-          g_error_free (error);
-
-          return FALSE;
-        }
+      self->gl_context = gdk_window_create_gl_context (window, error);
+      if (self->gl_context == NULL)
+        return FALSE;
     }
 
-  gdk_gl_context_realize (self->gl_context, &error);
-  if (error != NULL)
-    {
-      g_critical ("Unable to realize GL renderer: %s", error->message);
-      g_error_free (error);
-      return FALSE;
-    }
+  if (!gdk_gl_context_realize (self->gl_context, error))
+    return FALSE;
 
   gdk_gl_context_make_current (self->gl_context);
 
@@ -315,7 +307,7 @@ gsk_gl_renderer_realize (GskRenderer *renderer,
   self->gl_profiler = gsk_gl_profiler_new (self->gl_context);
 
   GSK_NOTE (OPENGL, g_print ("Creating buffers and programs\n"));
-  if (!gsk_gl_renderer_create_programs (self))
+  if (!gsk_gl_renderer_create_programs (self, error))
     return FALSE;
 
   return TRUE;
diff --git a/gsk/gskrenderer.c b/gsk/gskrenderer.c
index 629551c..86e262c 100644
--- a/gsk/gskrenderer.c
+++ b/gsk/gskrenderer.c
@@ -97,8 +97,9 @@ static GParamSpec *gsk_renderer_properties[N_PROPS];
   g_critical ("Renderer of type '%s' does not implement GskRenderer::" # method, G_OBJECT_TYPE_NAME (obj))
 
 static gboolean
-gsk_renderer_real_realize (GskRenderer *self,
-                           GdkWindow   *window)
+gsk_renderer_real_realize (GskRenderer  *self,
+                           GdkWindow    *window,
+                           GError      **error)
 {
   GSK_RENDERER_WARN_NOT_IMPLEMENTED_METHOD (self, realize);
   return FALSE;
@@ -528,6 +529,7 @@ gsk_renderer_is_realized (GskRenderer *renderer)
  * gsk_renderer_realize:
  * @renderer: a #GskRenderer
  * @window: the #GdkWindow renderer will be used on
+ * @error: return location for an error
  *
  * Creates the resources needed by the @renderer to render the scene
  * graph.
@@ -535,18 +537,20 @@ gsk_renderer_is_realized (GskRenderer *renderer)
  * Since: 3.90
  */
 gboolean
-gsk_renderer_realize (GskRenderer *renderer,
-                      GdkWindow   *window)
+gsk_renderer_realize (GskRenderer  *renderer,
+                      GdkWindow    *window,
+                      GError      **error)
 {
   GskRendererPrivate *priv = gsk_renderer_get_instance_private (renderer);
 
   g_return_val_if_fail (GSK_IS_RENDERER (renderer), FALSE);
   g_return_val_if_fail (!gsk_renderer_is_realized (renderer), FALSE);
   g_return_val_if_fail (GDK_IS_WINDOW (window), FALSE);
+  g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
 
   priv->window = g_object_ref (window);
 
-  if (!GSK_RENDERER_GET_CLASS (renderer)->realize (renderer, window))
+  if (!GSK_RENDERER_GET_CLASS (renderer)->realize (renderer, window, error))
     {
       g_clear_object (&priv->window);
       return FALSE;
@@ -750,6 +754,7 @@ gsk_renderer_new_for_window (GdkWindow *window)
 {
   GType renderer_type;
   GskRenderer *renderer;
+  GError *error = NULL;
   guint i;
 
   g_return_val_if_fail (GDK_IS_WINDOW (window), NULL);
@@ -764,7 +769,7 @@ gsk_renderer_new_for_window (GdkWindow *window)
                                "display", gdk_window_get_display (window),
                                NULL);
 
-      if (gsk_renderer_realize (renderer, window))
+      if (gsk_renderer_realize (renderer, window, &error))
         {
           GSK_NOTE (RENDERER, g_print ("Using renderer of type '%s' for display '%s'\n",
                                        G_OBJECT_TYPE_NAME (renderer),
@@ -772,10 +777,12 @@ gsk_renderer_new_for_window (GdkWindow *window)
           return renderer;
         }
 
-      GSK_NOTE (RENDERER, g_print ("Failed to realize renderer of type '%s' for window '%s'\n",
+      GSK_NOTE (RENDERER, g_print ("Failed to realize renderer of type '%s' for window '%s': %s\n",
                                    G_OBJECT_TYPE_NAME (renderer),
-                                   G_OBJECT_TYPE_NAME (window)));
+                                   G_OBJECT_TYPE_NAME (window),
+                                   error->message));
       g_object_unref (renderer);
+      g_clear_error (&error);
     }
 
   g_assert_not_reached ();
@@ -850,7 +857,7 @@ gsk_renderer_create_fallback (GskRenderer           *renderer,
                       NULL);
 
   gsk_renderer_set_cairo_context (res, cr);
-  gsk_renderer_realize (res, priv->window);
+  gsk_renderer_realize (res, priv->window, NULL);
 
   return res;
 }
diff --git a/gsk/gskrenderer.h b/gsk/gskrenderer.h
index 646ba6d..722259f 100644
--- a/gsk/gskrenderer.h
+++ b/gsk/gskrenderer.h
@@ -63,7 +63,8 @@ GdkDisplay *            gsk_renderer_get_display                (GskRenderer
 
 GDK_AVAILABLE_IN_3_90
 gboolean                gsk_renderer_realize                    (GskRenderer             *renderer,
-                                                                 GdkWindow               *window);
+                                                                 GdkWindow               *window,
+                                                                 GError                 **error);
 GDK_AVAILABLE_IN_3_90
 void                    gsk_renderer_unrealize                  (GskRenderer             *renderer);
 
diff --git a/gsk/gskrendererprivate.h b/gsk/gskrendererprivate.h
index 41064fb..eae8412 100644
--- a/gsk/gskrendererprivate.h
+++ b/gsk/gskrendererprivate.h
@@ -38,7 +38,8 @@ struct _GskRendererClass
   GObjectClass parent_class;
 
   gboolean (* realize) (GskRenderer *renderer,
-                        GdkWindow *window);
+                        GdkWindow *window,
+                        GError **error);
   void (* unrealize) (GskRenderer *renderer);
 
   void (* render) (GskRenderer *renderer,