Index: ChangeLog
===================================================================
--- ChangeLog	(revision 1174)
+++ ChangeLog	(revision 1175)
@@ -1,5 +1,16 @@
 2008-08-26  Dominic Lachowicz <domlachowicz@gmail.com>
 
+	* rsvg-cairo.h: Make cairo render functions return a gboolean. Returns TRUE
+	if the image can't be rendered
+	* rsvg.c: Check && handle the return value
+	* rsvg-cairo-render.c: Implement the above. Also, return FALSE if we're asked
+	to render an ID that doesn't exist
+
+	Collectively, fixes #540383 - rsvg_handle_render_cairo_sub - if ID not found, 
+	return an error and/or dont render whole SVG
+	
+2008-08-26  Dominic Lachowicz <domlachowicz@gmail.com>
+
 	* rsvg-private.h: #539488 - migrate use of GMemChunk to GSlice, from Felix Riemann
 	* rsvg-base.c: ditto
 	* rsvg-styles.c: ditto
Index: rsvg.c
===================================================================
--- rsvg.c	(revision 1174)
+++ rsvg.c	(revision 1175)
@@ -94,23 +94,26 @@
     surface = cairo_image_surface_create_for_data (pixels,
                                                    CAIRO_FORMAT_ARGB32,
                                                    dimensions.width, dimensions.height, rowstride);
-
     cr = cairo_create (surface);
+    cairo_surface_destroy (surface);
 
-    rsvg_handle_render_cairo_sub (handle, cr, id);
-    rsvg_cairo_to_pixbuf (pixels, rowstride, dimensions.height);
+    if (rsvg_handle_render_cairo_sub (handle, cr, id)) {
+		rsvg_cairo_to_pixbuf (pixels, rowstride, dimensions.height);
 
-    output = gdk_pixbuf_new_from_data (pixels,
-                                       GDK_COLORSPACE_RGB,
-                                       TRUE,
-                                       8,
-                                       dimensions.width,
-                                       dimensions.height,
-                                       rowstride,
-                                       (GdkPixbufDestroyNotify) rsvg_pixmap_destroy, NULL);
+		output = gdk_pixbuf_new_from_data (pixels,
+										   GDK_COLORSPACE_RGB,
+										   TRUE,
+										   8,
+										   dimensions.width,
+										   dimensions.height,
+										   rowstride,
+										   (GdkPixbufDestroyNotify) rsvg_pixmap_destroy, NULL);
+	} else {
+		g_free (pixels);
+		output = NULL;
+	}
 
     cairo_destroy (cr);
-    cairo_surface_destroy (surface);
 
     return output;
 }
Index: rsvg-cairo.h
===================================================================
--- rsvg-cairo.h	(revision 1174)
+++ rsvg-cairo.h	(revision 1175)
@@ -29,8 +29,8 @@
 
 G_BEGIN_DECLS 
 
-void	rsvg_handle_render_cairo     (RsvgHandle * handle, cairo_t * cr);
-void	rsvg_handle_render_cairo_sub (RsvgHandle * handle, cairo_t * cr, const char *id);
+gboolean	rsvg_handle_render_cairo     (RsvgHandle * handle, cairo_t * cr);
+gboolean	rsvg_handle_render_cairo_sub (RsvgHandle * handle, cairo_t * cr, const char *id);
 
 G_END_DECLS
 
Index: rsvg-cairo-render.c
===================================================================
--- rsvg-cairo-render.c	(revision 1174)
+++ rsvg-cairo-render.c	(revision 1175)
@@ -196,24 +196,29 @@
  *
  * Since: 2.14
  */
-void
+gboolean
 rsvg_handle_render_cairo_sub (RsvgHandle * handle, cairo_t * cr, const char *id)
 {
     RsvgDrawingCtx *draw;
     RsvgNode *drawsub = NULL;
 
-    g_return_if_fail (handle != NULL);
+    g_return_val_if_fail (handle != NULL, FALSE);
 
     if (!handle->priv->finished)
-        return;
+        return FALSE;
 
+    if (id && *id)
+        drawsub = rsvg_defs_lookup (handle->priv->defs, id);
+
+	if (drawsub == NULL && id != NULL) {
+		/* todo: there's no way to signal that @id doesn't exist */
+		return FALSE;
+	}
+
     draw = rsvg_cairo_new_drawing_ctx (cr, handle);
     if (!draw)
-        return;
+        return FALSE;
 
-    if (id && *id)
-        drawsub = rsvg_defs_lookup (handle->priv->defs, id);
-
     while (drawsub != NULL) {
         draw->drawsub_stack = g_slist_prepend (draw->drawsub_stack, drawsub);
         drawsub = drawsub->parent;
@@ -227,6 +232,8 @@
     cairo_restore (cr);
     rsvg_state_pop (draw);
     rsvg_drawing_ctx_free (draw);
+
+	return TRUE;
 }
 
 /**
@@ -238,8 +245,8 @@
  *
  * Since: 2.14
  */
-void
+gboolean
 rsvg_handle_render_cairo (RsvgHandle * handle, cairo_t * cr)
 {
-    rsvg_handle_render_cairo_sub (handle, cr, NULL);
+    return rsvg_handle_render_cairo_sub (handle, cr, NULL);
 }