[gtk+/gtk-3-2] [Quartz Bug 663182] NSImage throws an exception from _gtk_quartz_create_image_from_pixbuf()"

[John Ralls <jralls src gnome org>]

commit 9d900681d74cce1f58acbd5ee325f0e6c1af2941
Author: John Ralls <jralls ceridwen us>
Date:   Mon Nov 7 14:25:08 2011 -0800

    [Quartz Bug 663182] NSImage throws an exception from _gtk_quartz_create_image_from_pixbuf()"
    
    If a zero-sized NSImage calls lockfocus it throws an exception. Make sure that the image isn't zero-sized before calling lockfocus, and log a warning and return NULL if it is zero-sized.
    
    Have the quartz version of gtk_drag_begin_idle return FALSE if the returned image is NULL.

 gtk/gtkdnd-quartz.c |    5 +++++
 gtk/gtkquartz.c     |    9 +++++++++
 2 files changed, 14 insertions(+), 0 deletions(-)
---
diff --git a/gtk/gtkdnd-quartz.c b/gtk/gtkdnd-quartz.c
index 0653261..90506c1 100644
--- a/gtk/gtkdnd-quartz.c
+++ b/gtk/gtkdnd-quartz.c
@@ -1081,6 +1081,11 @@ gtk_drag_begin_idle (gpointer arg)
   point = [info->nsevent locationInWindow];
 
   drag_image = _gtk_quartz_create_image_from_pixbuf (info->icon_pixbuf);
+  if (drag_image == NULL)
+    {
+      g_object_unref (info->context);
+      return FALSE;
+    }
 
   point.x -= info->hot_x;
   point.y -= info->hot_y;
diff --git a/gtk/gtkquartz.c b/gtk/gtkquartz.c
index 7f36e9e..5d43766 100644
--- a/gtk/gtkquartz.c
+++ b/gtk/gtkquartz.c
@@ -35,9 +35,11 @@ _gtk_quartz_create_image_from_pixbuf (GdkPixbuf *pixbuf)
   int rowstride, pixbuf_width, pixbuf_height;
   gboolean has_alpha;
   NSImage *nsimage;
+  NSSize nsimage_size;
 
   pixbuf_width = gdk_pixbuf_get_width (pixbuf);
   pixbuf_height = gdk_pixbuf_get_height (pixbuf);
+  g_return_val_if_fail (pixbuf_width == 0 || pixbuf_height == 0, NULL);
   rowstride = gdk_pixbuf_get_rowstride (pixbuf);
   has_alpha = gdk_pixbuf_get_has_alpha (pixbuf);
 
@@ -57,6 +59,13 @@ _gtk_quartz_create_image_from_pixbuf (GdkPixbuf *pixbuf)
   CGColorSpaceRelease (colorspace);
 
   nsimage = [[NSImage alloc] initWithSize:NSMakeSize (pixbuf_width, pixbuf_height)];
+  nsimage_size = [nsimage size];
+  if (nsimage_size.width == 0.0 && nsimage_size.height == 0.0)
+    {
+      [nsimage release];
+      g_critical ("%s returned a zero-sized image", G_STRFUNC);
+      return NULL;
+    }
   [nsimage lockFocus];
 
   context = (CGContextRef)[[NSGraphicsContext currentContext] graphicsPort];