[librsvg/gnome-3-2] Don't create pixbufs with zero width or height

[Christian Persch <chpe src gnome org>]

commit ef28ade7613ed0ba8ef00b8afd3cea4e23e23055
Author: Christian Persch <chpe gnome org>
Date:   Wed Nov 9 21:00:53 2011 +0100

    Don't create pixbufs with zero width or height
    
    This created lots and lots of critical warnings when rendering
    tests/svg1.1/svg/filters-displace-01-f.svg:
    
    GdkPixbuf-CRITICAL **: gdk_pixbuf_new: assertion `width > 0' failed
    g_logv() [gmessages.c:779]
    g_log() [gmessages.c:826]
    g_return_if_fail_warning() [gmessages.c:838]
    gdk_pixbuf_new() [gdk-pixbuf.c:338]
    rsvg_filter_primitive_image_render_ext() [rsvg-filter.c:3376]

 rsvg-filter.c |   11 +++++++----
 1 files changed, 7 insertions(+), 4 deletions(-)
---
diff --git a/rsvg-filter.c b/rsvg-filter.c
index d358de5..5d071e7 100644
--- a/rsvg-filter.c
+++ b/rsvg-filter.c
@@ -3362,6 +3362,7 @@ rsvg_filter_primitive_image_render_ext (RsvgFilterPrimitive * self, RsvgFilterCo
     unsigned char *pixels;
     int channelmap[4];
     int length;
+    int width, height;
 
     upself = (RsvgFilterPrimitiveImage *) self;
 
@@ -3370,15 +3371,18 @@ rsvg_filter_primitive_image_render_ext (RsvgFilterPrimitive * self, RsvgFilterCo
 
     boundarys = rsvg_filter_primitive_get_bounds (self, ctx);
 
+    width = boundarys.x1 - boundarys.x0;
+    height = boundarys.y1 - boundarys.y0;
+    if (width == 0 || height == 0)
+        return NULL;
+
     img = rsvg_pixbuf_new_from_href (upself->href->str,
                                      rsvg_handle_get_base_uri (upself->ctx), NULL);
 
     if (!img)
         return NULL;
 
-
-    intermediate = gdk_pixbuf_new (GDK_COLORSPACE_RGB, 1, 8, boundarys.x1 - boundarys.x0,
-                                   boundarys.y1 - boundarys.y0);
+    intermediate = gdk_pixbuf_new (GDK_COLORSPACE_RGB, 1, 8, width, height);
 
 
     rsvg_art_affine_image (img, intermediate,
@@ -3391,7 +3395,6 @@ rsvg_filter_primitive_image_render_ext (RsvgFilterPrimitive * self, RsvgFilterCo
         return NULL;
     }
 
-
     g_object_unref (img);
 
     length = gdk_pixbuf_get_height (intermediate) * gdk_pixbuf_get_rowstride (intermediate);