Resolves: tdf#108903 avoid recurse to death

Change-Id: Iadde719a024c5fce97aa0f4c58947a5012639a84
Reviewed-on: https://gerrit.libreoffice.org/39918Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>

svgio/inc/svgusenode.hxx

@@ -45,6 +45,8 @@ namespace svgio
             /// link to content. If maXLink is set, the node can be fetched
             // on demand
             OUString               maXLink;
+            /// detect if maXLink causes a loop to ourself during decomposing
+            mutable bool           mbDecomposingSvgNode;
 
         public:
             SvgUseNode(

svgio/source/svgreader/svgusenode.cxx

@@ -35,7 +35,8 @@ namespace svgio
             maY(),
             maWidth(),
             maHeight(),
-            maXLink()
+            maXLink(),
+            mbDecomposingSvgNode(false)
         {
         }
 
@@ -142,7 +143,7 @@ namespace svgio
             // try to access link to content
             const SvgNode* pXLink = getDocument().findSvgNodeById(maXLink);
 
-            if(pXLink && Display_none != pXLink->getDisplay())
+            if (pXLink && Display_none != pXLink->getDisplay() && !mbDecomposingSvgNode)
             {
                 // decompose children
                 drawinglayer::primitive2d::Primitive2DContainer aNewTarget;
@@ -150,9 +151,11 @@ namespace svgio
                 // todo: in case mpXLink is a SVGTokenSvg or SVGTokenSymbol the
                 // SVG docs want the getWidth() and getHeight() from this node
                 // to be valid for the subtree.
+                mbDecomposingSvgNode = true;
                 const_cast< SvgNode* >(pXLink)->setAlternativeParent(this);
                 pXLink->decomposeSvgNode(aNewTarget, true);
                 const_cast< SvgNode* >(pXLink)->setAlternativeParent();
+                mbDecomposingSvgNode = true;
 
                 if(!aNewTarget.empty())
                 {