avoid infinite regress in busted documents

Change-Id: I639617e41cd9a9a51a3dd3efa32ac1cf2991b9d2

lotuswordpro/source/filter/xfilter/xfcontent.hxx

@@ -92,14 +92,28 @@ public:
      */
     OUString   GetStyleName() {return m_strStyleName;}
 
-    virtual void ToXml(IXFStream * stream) = 0;
+    void DoToXml(IXFStream* stream)
+    {
+        if (m_bDoingToXml)
+            throw std::runtime_error("recursion in content");
+        m_bDoingToXml = true;
+        ToXml(stream);
+        m_bDoingToXml = false;
+    }
 
 protected:
-    XFContent() {}
+    XFContent()
+        : m_bDoingToXml(false)
+    {
+    }
+
+    virtual void ToXml(IXFStream* stream) = 0;
 
     virtual ~XFContent() {}
 
-    OUString   m_strStyleName;
+    OUString m_strStyleName;
+private:
+    bool m_bDoingToXml;
 };
 
 #endif

lotuswordpro/source/filter/xfilter/xfcontentcontainer.cxx

@@ -131,7 +131,7 @@ void    XFContentContainer::ToXml(IXFStream *pStrm)
     {
         XFContent *pContent = it->get();
         if( pContent )
-            pContent->ToXml(pStrm);
+            pContent->DoToXml(pStrm);
     }
 }
 

lotuswordpro/source/filter/xfilter/xftextspan.cxx

@@ -112,7 +112,7 @@ void    XFTextSpan::ToXml(IXFStream *pStrm)
     {
         XFContent *pContent = it->get();
         if( pContent )
-            pContent->ToXml(pStrm);
+            pContent->DoToXml(pStrm);
     }
 
     pStrm->EndElement( "text:span" );
@@ -135,7 +135,7 @@ void    XFTextSpanStart::ToXml(IXFStream *pStrm)
     {
         XFContent *pContent = it->get();
         if( pContent )
-            pContent->ToXml(pStrm);
+            pContent->DoToXml(pStrm);
     }
 }
 void    XFTextSpanEnd::ToXml(IXFStream *pStrm)
@@ -145,7 +145,7 @@ void    XFTextSpanEnd::ToXml(IXFStream *pStrm)
     {
         XFContent *pContent = it->get();
         if( pContent )
-            pContent->ToXml(pStrm);
+            pContent->DoToXml(pStrm);
     }
     pStrm->EndElement( "text:span" );
 }