Fix for circular references detection in almost all cases, fixing https://bugs.launchpad.net/inkscape/+bug/167247 and a few of its duplicates.

This fix is aimed at preventing any sort of circular references with the URIReference::_acceptObject method, checking the absence of loops in the reference+child tree.

There can be some performance improvements done if we add a pointer from cloned sub-objects to their origin sub-object. 

The remaining cases that are not fixed can involve non-trivial loops using one or more "url()" stylesheet references. Being able to take them into account would require a non-obvious style.cpp refactoring making use of URIReference for this kind of reference (and not handling manually the signals in the styling code, which would probably be a good thing to do anyway)

(bzr r14245)

1 files changed, 1 insertions, 8 deletions

diff --git a/src/live_effects/lpeobject-reference.cpp b/src/live_effects/lpeobject-reference.cpp
index 573c8a2fd..d9de6e77f 100644
--- a/src/live_effects/lpeobject-reference.cpp
+++ b/src/live_effects/lpeobject-reference.cpp
@@ -43,14 +43,7 @@ LPEObjectReference::~LPEObjectReference(void)
 bool LPEObjectReference::_acceptObject(SPObject * const obj) const
 {
     if (IS_LIVEPATHEFFECT(obj)) {
-        SPObject * const owner = getOwner();
-        /* Refuse references to us or to an ancestor. */
-        for ( SPObject *iter = owner ; iter ; iter = iter->parent ) {
-            if ( iter == obj ) {
-                return false;
-            }
-        }
-        return true;
+        return URIReference::_acceptObject(obj);
     } else {
         return false;
     }