[gimp] Bug 763547 - GIMP git segfaults on exit when the airbrush tool is active

[Michael Natterer <mitch src gnome org>]

commit d588bff8bebd083d862ff47ddd7ba9e4673c099c
Author: Michael Natterer <mitch gimp org>
Date:   Sun Mar 13 13:07:22 2016 +0100

    Bug 763547 - GIMP git segfaults on exit when the airbrush tool is active
    
    Fix GimpAirbrush to not keep a GimpSymmetry instance around across
    paint strokes. The symmetry refs its drawable but lacks the code of
    dropping the reference when the drawable is removed from the image, or
    the image is closed.
    
    Also cleaned up gimp_airbrush_paint() a bit.

 app/paint/gimpairbrush.c |   36 ++++++++++++++++--------------------
 1 files changed, 16 insertions(+), 20 deletions(-)
---
diff --git a/app/paint/gimpairbrush.c b/app/paint/gimpairbrush.c
index 29dcc85..dea4b8c 100644
--- a/app/paint/gimpairbrush.c
+++ b/app/paint/gimpairbrush.c
@@ -48,6 +48,7 @@ static void       gimp_airbrush_motion   (GimpPaintCore    *paint_core,
                                           GimpDrawable     *drawable,
                                           GimpPaintOptions *paint_options,
                                           GimpSymmetry     *sym);
+
 static gboolean   gimp_airbrush_timeout  (gpointer          data);
 
 
@@ -82,8 +83,6 @@ gimp_airbrush_class_init (GimpAirbrushClass *klass)
 static void
 gimp_airbrush_init (GimpAirbrush *airbrush)
 {
-  airbrush->timeout_id = 0;
-  airbrush->sym    = NULL;
 }
 
 static void
@@ -98,7 +97,10 @@ gimp_airbrush_finalize (GObject *object)
     }
 
   if (airbrush->sym)
-    g_object_unref (airbrush->sym);
+    {
+      g_object_unref (airbrush->sym);
+      airbrush->sym = NULL;
+    }
 
   G_OBJECT_CLASS (parent_class)->finalize (object);
 }
@@ -115,15 +117,15 @@ gimp_airbrush_paint (GimpPaintCore    *paint_core,
   GimpAirbrushOptions *options  = GIMP_AIRBRUSH_OPTIONS (paint_options);
   GimpDynamics        *dynamics = GIMP_BRUSH_CORE (paint_core)->dynamics;
 
+  if (airbrush->timeout_id)
+    {
+      g_source_remove (airbrush->timeout_id);
+      airbrush->timeout_id = 0;
+    }
+
   switch (paint_state)
     {
     case GIMP_PAINT_STATE_INIT:
-      if (airbrush->timeout_id)
-        {
-          g_source_remove (airbrush->timeout_id);
-          airbrush->timeout_id = 0;
-        }
-
       GIMP_PAINT_CORE_CLASS (parent_class)->paint (paint_core, drawable,
                                                    paint_options,
                                                    sym,
@@ -131,15 +133,9 @@ gimp_airbrush_paint (GimpPaintCore    *paint_core,
       break;
 
     case GIMP_PAINT_STATE_MOTION:
-      if (airbrush->timeout_id)
-        {
-          g_source_remove (airbrush->timeout_id);
-          airbrush->timeout_id = 0;
-        }
-
       gimp_airbrush_motion (paint_core, drawable, paint_options, sym);
 
-      if ((options->rate != 0.0) && (!options->motion_only))
+      if ((options->rate != 0.0) && ! options->motion_only)
         {
           GimpImage  *image = gimp_item_get_image (GIMP_ITEM (drawable));
           gdouble     fade_point;
@@ -175,10 +171,10 @@ gimp_airbrush_paint (GimpPaintCore    *paint_core,
       break;
 
     case GIMP_PAINT_STATE_FINISH:
-      if (airbrush->timeout_id)
+      if (airbrush->sym)
         {
-          g_source_remove (airbrush->timeout_id);
-          airbrush->timeout_id = 0;
+          g_object_unref (airbrush->sym);
+          airbrush->sym = NULL;
         }
 
       GIMP_PAINT_CORE_CLASS (parent_class)->paint (paint_core, drawable,
@@ -232,5 +228,5 @@ gimp_airbrush_timeout (gpointer data)
 
   gimp_image_flush (gimp_item_get_image (GIMP_ITEM (airbrush->drawable)));
 
-  return FALSE;
+  return G_SOURCE_REMOVE;
 }