Adding upstream version 1:7.0.4.upstream/1%7.0.4upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

12 files changed, 8820 insertions, 0 deletions

diff --git a/sax/source/expatwrap/expwrap.component b/sax/source/expatwrap/expwrap.component
new file mode 100644
index 000000000..1f72eccf3
--- /dev/null
+++ b/sax/source/expatwrap/expwrap.component
@@ -0,0 +1,38 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ -->
+
+<component loader="com.sun.star.loader.SharedLibrary" environment="@CPPU_ENV@"
+    xmlns="http://openoffice.org/2010/uno-components">
+  <implementation name="com.sun.star.comp.extensions.xml.sax.ParserExpat"
+      constructor="com_sun_star_comp_extensions_xml_sax_ParserExpat_get_implementation">
+    <service name="com.sun.star.xml.sax.Parser"/>
+  </implementation>
+  <implementation name="com.sun.star.extensions.xml.sax.Writer"
+      constructor="com_sun_star_extensions_xml_sax_Writer_get_implementation">
+    <service name="com.sun.star.xml.sax.Writer"/>
+  </implementation>
+  <implementation name="com.sun.star.comp.extensions.xml.sax.FastParser"
+      constructor="com_sun_star_comp_extensions_xml_sax_FastParser_get_implementation">
+     <service name="com.sun.star.xml.sax.FastParser"/>
+  </implementation>
+  <implementation name="com.sun.star.comp.extensions.xml.sax.LegacyFastParser"
+      constructor="com_sun_star_comp_extensions_xml_sax_LegacyFastParser_get_implementation">
+     <service name="com.sun.star.xml.sax.LegacyFastParser"/>
+  </implementation>
+</component>
diff --git a/sax/source/expatwrap/sax_expat.cxx b/sax/source/expatwrap/sax_expat.cxx
new file mode 100644
index 000000000..b80ebf033
--- /dev/null
+++ b/sax/source/expatwrap/sax_expat.cxx
@@ -0,0 +1,959 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <string.h>
+#include <cassert>
+#include <memory>
+#include <utility>
+#include <vector>
+
+
+#include <com/sun/star/lang/XServiceInfo.hpp>
+#include <com/sun/star/lang/XInitialization.hpp>
+#include <com/sun/star/uno/XComponentContext.hpp>
+#include <com/sun/star/xml/sax/XExtendedDocumentHandler.hpp>
+#include <com/sun/star/xml/sax/XParser.hpp>
+#include <com/sun/star/xml/sax/SAXParseException.hpp>
+#include <com/sun/star/io/IOException.hpp>
+#include <com/sun/star/io/XSeekable.hpp>
+#include <com/sun/star/lang/WrappedTargetRuntimeException.hpp>
+
+#include <comphelper/attributelist.hxx>
+#include <cppuhelper/weak.hxx>
+#include <cppuhelper/implbase.hxx>
+#include <cppuhelper/supportsservice.hxx>
+#include <rtl/ref.hxx>
+#include <sal/log.hxx>
+
+#include <expat.h>
+
+using namespace ::std;
+using namespace ::osl;
+using namespace ::cppu;
+using namespace ::com::sun::star::lang;
+using namespace ::com::sun::star::xml::sax;
+using namespace ::com::sun::star::io;
+
+#include <xml2utf.hxx>
+
+namespace {
+
+#define XML_CHAR_TO_OUSTRING(x) OUString(x , strlen( x ), RTL_TEXTENCODING_UTF8)
+#define XML_CHAR_N_TO_USTRING(x,n) OUString(x,n, RTL_TEXTENCODING_UTF8 )
+
+
+/*
+* The following macro encapsulates any call to an event handler.
+* It ensures, that exceptions thrown by the event handler are
+* treated properly.
+*/
+#define CALL_ELEMENT_HANDLER_AND_CARE_FOR_EXCEPTIONS(pThis,call) \
+    if( ! pThis->bExceptionWasThrown ) { \
+        try {\
+            pThis->call;\
+        }\
+        catch( const SAXParseException &e ) {\
+            callErrorHandler( pThis ,  e );\
+         }\
+        catch( const SAXException &e ) {\
+            callErrorHandler( pThis , SAXParseException(\
+                                            e.Message, \
+                                            e.Context, \
+                                            e.WrappedException,\
+                                            pThis->rDocumentLocator->getPublicId(),\
+                                            pThis->rDocumentLocator->getSystemId(),\
+                                            pThis->rDocumentLocator->getLineNumber(),\
+                                            pThis->rDocumentLocator->getColumnNumber()\
+                                     ) );\
+        }\
+        catch( const css::uno::RuntimeException &e ) {\
+            pThis->bExceptionWasThrown = true; \
+            pThis->bRTExceptionWasThrown = true; \
+            pImpl->rtexception = e; \
+        }\
+        catch( const css::uno::Exception &e ) {\
+            pThis->bExceptionWasThrown = true; \
+            pThis->bRTExceptionWasThrown = true; \
+            pImpl->rtexception = WrappedTargetRuntimeException("Non-runtime UNO exception caught during parse", e.Context, makeAny(e)); \
+        }\
+    }\
+    ((void)0)
+
+
+class SaxExpatParser_Impl;
+
+// This class implements the external Parser interface
+class SaxExpatParser
+    : public WeakImplHelper< XInitialization
+                            , XServiceInfo
+                            , XParser >
+{
+
+public:
+    SaxExpatParser();
+
+    // css::lang::XInitialization:
+    virtual void SAL_CALL initialize(css::uno::Sequence<css::uno::Any> const& rArguments) override;
+
+    // The SAX-Parser-Interface
+    virtual void SAL_CALL parseStream(  const InputSource& structSource) override;
+    virtual void SAL_CALL setDocumentHandler(const css::uno::Reference< XDocumentHandler > & xHandler) override;
+
+    virtual void SAL_CALL setErrorHandler(const css::uno::Reference< XErrorHandler > & xHandler) override;
+    virtual void SAL_CALL setDTDHandler(const css::uno::Reference < XDTDHandler > & xHandler) override;
+    virtual void SAL_CALL setEntityResolver(const css::uno::Reference<  XEntityResolver >& xResolver) override;
+
+    virtual void SAL_CALL setLocale( const Locale &locale ) override;
+
+public: // XServiceInfo
+    OUString                     SAL_CALL getImplementationName() override;
+    css::uno::Sequence< OUString >         SAL_CALL getSupportedServiceNames() override;
+    sal_Bool                     SAL_CALL supportsService(const OUString& ServiceName) override;
+
+private:
+    std::unique_ptr<SaxExpatParser_Impl>   m_pImpl;
+};
+
+
+// Entity binds all information needed for a single file
+struct Entity
+{
+    InputSource         structSource;
+    XML_Parser          pParser;
+    sax_expatwrap::XMLFile2UTFConverter converter;
+};
+
+
+static constexpr OUStringLiteral gsCDATA = "CDATA";
+
+class SaxExpatParser_Impl
+{
+public: // module scope
+    Mutex               aMutex;
+    bool m_bEnableDoS; // fdo#60471 thank you Adobe Illustrator
+
+    css::uno::Reference< XDocumentHandler >   rDocumentHandler;
+    css::uno::Reference< XExtendedDocumentHandler > rExtendedDocumentHandler;
+
+    css::uno::Reference< XErrorHandler >  rErrorHandler;
+    css::uno::Reference< XDTDHandler >    rDTDHandler;
+    css::uno::Reference< XEntityResolver > rEntityResolver;
+    css::uno::Reference < XLocator >      rDocumentLocator;
+
+
+    rtl::Reference < comphelper::AttributeList > rAttrList;
+
+    // External entity stack
+    vector<struct Entity>   vecEntity;
+    void pushEntity( Entity &&entity )
+        { vecEntity.push_back( std::move(entity) ); }
+    void popEntity()
+        { vecEntity.pop_back( ); }
+    struct Entity &getEntity()
+        { return vecEntity.back(); }
+
+
+    // Exception cannot be thrown through the C-XmlParser (possible resource leaks),
+    // therefore the exception must be saved somewhere.
+    SAXParseException   exception;
+    css::uno::RuntimeException    rtexception;
+    bool                bExceptionWasThrown;
+    bool                bRTExceptionWasThrown;
+
+public:
+    SaxExpatParser_Impl()
+        : m_bEnableDoS(false)
+        , bExceptionWasThrown(false)
+        , bRTExceptionWasThrown(false)
+    {
+    }
+
+    // the C-Callbacks for the expat parser
+    void static callbackStartElement(void *userData, const XML_Char *name , const XML_Char **atts);
+    void static callbackEndElement(void *userData, const XML_Char *name);
+    void static callbackCharacters( void *userData , const XML_Char *s , int nLen );
+    void static callbackProcessingInstruction(  void *userData ,
+                                                const XML_Char *sTarget ,
+                                                const XML_Char *sData );
+
+    void static callbackEntityDecl( void *userData ,
+                                    const XML_Char *entityName,
+                                    int is_parameter_entity,
+                                    const XML_Char *value,
+                                    int value_length,
+                                    const XML_Char *base,
+                                    const XML_Char *systemId,
+                                    const XML_Char *publicId,
+                                    const XML_Char *notationName);
+
+    void static callbackNotationDecl(   void *userData,
+                                        const XML_Char *notationName,
+                                        const XML_Char *base,
+                                        const XML_Char *systemId,
+                                        const XML_Char *publicId);
+
+    bool static callbackExternalEntityRef(   XML_Parser parser,
+                                            const XML_Char *openEntityNames,
+                                            const XML_Char *base,
+                                            const XML_Char *systemId,
+                                            const XML_Char *publicId);
+
+    int static callbackUnknownEncoding(void *encodingHandlerData,
+                                                  const XML_Char *name,
+                                                  XML_Encoding *info);
+
+    void static callbackDefault( void *userData,  const XML_Char *s,  int len);
+
+    void static callbackStartCDATA( void *userData );
+    void static callbackEndCDATA( void *userData );
+    void static callbackComment( void *userData , const XML_Char *s );
+    void static callErrorHandler( SaxExpatParser_Impl *pImpl , const SAXParseException &e );
+
+public:
+    void parse();
+};
+
+extern "C"
+{
+    static void call_callbackStartElement(void *userData, const XML_Char *name , const XML_Char **atts)
+    {
+        SaxExpatParser_Impl::callbackStartElement(userData,name,atts);
+    }
+    static void call_callbackEndElement(void *userData, const XML_Char *name)
+    {
+        SaxExpatParser_Impl::callbackEndElement(userData,name);
+    }
+    static void call_callbackCharacters( void *userData , const XML_Char *s , int nLen )
+    {
+        SaxExpatParser_Impl::callbackCharacters(userData,s,nLen);
+    }
+    static void call_callbackProcessingInstruction(void *userData,const XML_Char *sTarget,const XML_Char *sData )
+    {
+        SaxExpatParser_Impl::callbackProcessingInstruction(userData,sTarget,sData );
+    }
+    static void call_callbackEntityDecl(void *userData ,
+                                        const XML_Char *entityName,
+                                        int is_parameter_entity,
+                                        const XML_Char *value,
+                                        int value_length,
+                                        const XML_Char *base,
+                                        const XML_Char *systemId,
+                                        const XML_Char *publicId,
+                                        const XML_Char *notationName)
+    {
+        SaxExpatParser_Impl::callbackEntityDecl(userData, entityName,
+                is_parameter_entity, value, value_length,
+                base, systemId, publicId, notationName);
+    }
+    static void call_callbackNotationDecl(void *userData,
+                                          const XML_Char *notationName,
+                                          const XML_Char *base,
+                                          const XML_Char *systemId,
+                                          const XML_Char *publicId)
+    {
+        SaxExpatParser_Impl::callbackNotationDecl(userData,notationName,base,systemId,publicId);
+    }
+    static int call_callbackExternalEntityRef(XML_Parser parser,
+                                              const XML_Char *openEntityNames,
+                                              const XML_Char *base,
+                                              const XML_Char *systemId,
+                                              const XML_Char *publicId)
+    {
+        return SaxExpatParser_Impl::callbackExternalEntityRef(parser,openEntityNames,base,systemId,publicId);
+    }
+    static int call_callbackUnknownEncoding(void *encodingHandlerData,
+                                              const XML_Char *name,
+                                            XML_Encoding *info)
+    {
+        return SaxExpatParser_Impl::callbackUnknownEncoding(encodingHandlerData,name,info);
+    }
+    static void call_callbackDefault( void *userData,  const XML_Char *s,  int len)
+    {
+        SaxExpatParser_Impl::callbackDefault(userData,s,len);
+    }
+    static void call_callbackStartCDATA( void *userData )
+    {
+        SaxExpatParser_Impl::callbackStartCDATA(userData);
+    }
+    static void call_callbackEndCDATA( void *userData )
+    {
+        SaxExpatParser_Impl::callbackEndCDATA(userData);
+    }
+    static void call_callbackComment( void *userData , const XML_Char *s )
+    {
+        SaxExpatParser_Impl::callbackComment(userData,s);
+    }
+}
+
+
+// LocatorImpl
+
+class LocatorImpl :
+    public WeakImplHelper< XLocator, css::io::XSeekable >
+    // should use a different interface for stream positions!
+{
+public:
+    explicit LocatorImpl(SaxExpatParser_Impl *p)
+        : m_pParser(p)
+    {
+    }
+
+public: //XLocator
+    virtual sal_Int32 SAL_CALL getColumnNumber() override
+    {
+        return XML_GetCurrentColumnNumber( m_pParser->getEntity().pParser );
+    }
+    virtual sal_Int32 SAL_CALL getLineNumber() override
+    {
+        return XML_GetCurrentLineNumber( m_pParser->getEntity().pParser );
+    }
+    virtual OUString SAL_CALL getPublicId() override
+    {
+        return m_pParser->getEntity().structSource.sPublicId;
+    }
+    virtual OUString SAL_CALL getSystemId() override
+    {
+        return m_pParser->getEntity().structSource.sSystemId;
+    }
+
+    // XSeekable (only for getPosition)
+
+    virtual void SAL_CALL seek( sal_Int64 ) override
+    {
+    }
+    virtual sal_Int64 SAL_CALL getPosition() override
+    {
+        return XML_GetCurrentByteIndex( m_pParser->getEntity().pParser );
+    }
+    virtual ::sal_Int64 SAL_CALL getLength() override
+    {
+        return 0;
+    }
+
+private:
+
+    SaxExpatParser_Impl *m_pParser;
+};
+
+
+SaxExpatParser::SaxExpatParser(  )
+{
+    m_pImpl.reset( new SaxExpatParser_Impl );
+
+    LocatorImpl *pLoc = new LocatorImpl( m_pImpl.get() );
+    m_pImpl->rDocumentLocator.set( pLoc );
+
+    // Performance-improvement; handing out the same object with every call of
+    // the startElement callback is allowed (see sax-specification):
+    m_pImpl->rAttrList = new comphelper::AttributeList;
+
+    m_pImpl->bExceptionWasThrown = false;
+    m_pImpl->bRTExceptionWasThrown = false;
+}
+
+// css::lang::XInitialization:
+void SAL_CALL
+SaxExpatParser::initialize(css::uno::Sequence< css::uno::Any > const& rArguments)
+{
+    // possible arguments: a string "DoSmeplease"
+    if (rArguments.hasElements())
+    {
+        OUString str;
+        if ((rArguments[0] >>= str) && "DoSmeplease" == str)
+        {
+            MutexGuard guard( m_pImpl->aMutex );
+            m_pImpl->m_bEnableDoS = true;
+        }
+    }
+}
+
+class ParserCleanup
+{
+private:
+    SaxExpatParser_Impl& m_rParser;
+    XML_Parser m_xmlParser;
+public:
+    ParserCleanup(SaxExpatParser_Impl& rParser, XML_Parser xmlParser)
+        : m_rParser(rParser)
+        , m_xmlParser(xmlParser)
+    {
+    }
+    ~ParserCleanup()
+    {
+        m_rParser.popEntity();
+        //XML_ParserFree accepts a null arg
+        XML_ParserFree(m_xmlParser);
+    }
+};
+
+/***************
+*
+* parseStream does Parser-startup initializations. The SaxExpatParser_Impl::parse() method does
+* the file-specific initialization work. (During a parser run, external files may be opened)
+*
+****************/
+void SaxExpatParser::parseStream(   const InputSource& structSource)
+{
+    // Only one text at one time
+    MutexGuard guard( m_pImpl->aMutex );
+
+
+    struct Entity entity;
+    entity.structSource = structSource;
+
+    if( ! entity.structSource.aInputStream.is() )
+    {
+        throw SAXException("No input source",
+                            css::uno::Reference< css::uno::XInterface > () , css::uno::Any() );
+    }
+
+    entity.converter.setInputStream( entity.structSource.aInputStream );
+    if( !entity.structSource.sEncoding.isEmpty() )
+    {
+        entity.converter.setEncoding(
+            OUStringToOString( entity.structSource.sEncoding , RTL_TEXTENCODING_ASCII_US ) );
+    }
+
+    // create parser with proper encoding
+    entity.pParser = XML_ParserCreate( nullptr );
+    if( ! entity.pParser )
+    {
+        throw SAXException("Couldn't create parser",
+                            css::uno::Reference< css::uno::XInterface > (), css::uno::Any() );
+    }
+
+    // set all necessary C-Callbacks
+    XML_SetUserData( entity.pParser, m_pImpl.get() );
+    XML_SetElementHandler(  entity.pParser ,
+                            call_callbackStartElement ,
+                            call_callbackEndElement );
+    XML_SetCharacterDataHandler( entity.pParser , call_callbackCharacters );
+    XML_SetProcessingInstructionHandler(entity.pParser ,
+                                        call_callbackProcessingInstruction );
+    if (!m_pImpl->m_bEnableDoS)
+    {
+        XML_SetEntityDeclHandler(entity.pParser, call_callbackEntityDecl);
+    }
+    XML_SetNotationDeclHandler( entity.pParser, call_callbackNotationDecl );
+    XML_SetExternalEntityRefHandler(    entity.pParser,
+                                        call_callbackExternalEntityRef);
+    XML_SetUnknownEncodingHandler( entity.pParser,  call_callbackUnknownEncoding ,nullptr);
+
+    if( m_pImpl->rExtendedDocumentHandler.is() ) {
+
+        // These handlers just delegate calls to the ExtendedHandler. If no extended handler is
+        // given, these callbacks can be ignored
+        XML_SetDefaultHandlerExpand( entity.pParser, call_callbackDefault );
+        XML_SetCommentHandler( entity.pParser, call_callbackComment );
+        XML_SetCdataSectionHandler(     entity.pParser ,
+                                        call_callbackStartCDATA ,
+                                         call_callbackEndCDATA );
+    }
+
+
+    m_pImpl->exception = SAXParseException();
+    auto const xmlParser = entity.pParser;
+    m_pImpl->pushEntity( std::move(entity) );
+
+    ParserCleanup aEnsureFree(*m_pImpl, xmlParser);
+
+    // start the document
+    if( m_pImpl->rDocumentHandler.is() ) {
+        m_pImpl->rDocumentHandler->setDocumentLocator( m_pImpl->rDocumentLocator );
+        m_pImpl->rDocumentHandler->startDocument();
+    }
+
+    m_pImpl->parse();
+
+    // finish document
+    if( m_pImpl->rDocumentHandler.is() ) {
+        m_pImpl->rDocumentHandler->endDocument();
+    }
+}
+
+void SaxExpatParser::setDocumentHandler(const css::uno::Reference< XDocumentHandler > & xHandler)
+{
+    m_pImpl->rDocumentHandler = xHandler;
+    m_pImpl->rExtendedDocumentHandler =
+        css::uno::Reference< XExtendedDocumentHandler >( xHandler , css::uno::UNO_QUERY );
+}
+
+void SaxExpatParser::setErrorHandler(const css::uno::Reference< XErrorHandler > & xHandler)
+{
+    m_pImpl->rErrorHandler = xHandler;
+}
+
+void SaxExpatParser::setDTDHandler(const css::uno::Reference< XDTDHandler > & xHandler)
+{
+    m_pImpl->rDTDHandler = xHandler;
+}
+
+void SaxExpatParser::setEntityResolver(const css::uno::Reference < XEntityResolver > & xResolver)
+{
+    m_pImpl->rEntityResolver = xResolver;
+}
+
+
+void SaxExpatParser::setLocale( const Locale & )
+{
+    // not implemented
+}
+
+// XServiceInfo
+OUString SaxExpatParser::getImplementationName()
+{
+    return "com.sun.star.comp.extensions.xml.sax.ParserExpat";
+}
+
+// XServiceInfo
+sal_Bool SaxExpatParser::supportsService(const OUString& ServiceName)
+{
+    return cppu::supportsService(this, ServiceName);
+}
+
+// XServiceInfo
+css::uno::Sequence< OUString > SaxExpatParser::getSupportedServiceNames()
+{
+    return { "com.sun.star.xml.sax.Parser" };
+}
+
+
+/*---------------------------------------
+*
+* Helper functions and classes
+*
+*
+*-------------------------------------------*/
+OUString getErrorMessage( XML_Error xmlE, const OUString& sSystemId , sal_Int32 nLine )
+{
+    OUString Message;
+    if( XML_ERROR_NONE == xmlE ) {
+        Message = "No";
+    }
+    else if( XML_ERROR_NO_MEMORY == xmlE ) {
+        Message = "no memory";
+    }
+    else if( XML_ERROR_SYNTAX == xmlE ) {
+        Message = "syntax";
+    }
+    else if( XML_ERROR_NO_ELEMENTS == xmlE ) {
+        Message = "no elements";
+    }
+    else if( XML_ERROR_INVALID_TOKEN == xmlE ) {
+        Message = "invalid token";
+    }
+    else if( XML_ERROR_UNCLOSED_TOKEN == xmlE ) {
+        Message = "unclosed token";
+    }
+    else if( XML_ERROR_PARTIAL_CHAR == xmlE ) {
+        Message = "partial char";
+    }
+    else if( XML_ERROR_TAG_MISMATCH == xmlE ) {
+        Message = "tag mismatch";
+    }
+    else if( XML_ERROR_DUPLICATE_ATTRIBUTE == xmlE ) {
+        Message = "duplicate attribute";
+    }
+    else if( XML_ERROR_JUNK_AFTER_DOC_ELEMENT == xmlE ) {
+        Message = "junk after doc element";
+    }
+    else if( XML_ERROR_PARAM_ENTITY_REF == xmlE ) {
+        Message = "parameter entity reference";
+    }
+    else if( XML_ERROR_UNDEFINED_ENTITY == xmlE ) {
+        Message = "undefined entity";
+    }
+    else if( XML_ERROR_RECURSIVE_ENTITY_REF == xmlE ) {
+        Message = "recursive entity reference";
+    }
+    else if( XML_ERROR_ASYNC_ENTITY == xmlE ) {
+        Message = "async entity";
+    }
+    else if( XML_ERROR_BAD_CHAR_REF == xmlE ) {
+        Message = "bad char reference";
+    }
+    else if( XML_ERROR_BINARY_ENTITY_REF == xmlE ) {
+        Message = "binary entity reference";
+    }
+    else if( XML_ERROR_ATTRIBUTE_EXTERNAL_ENTITY_REF == xmlE ) {
+        Message = "attribute external entity reference";
+    }
+    else if( XML_ERROR_MISPLACED_XML_PI == xmlE ) {
+        Message = "misplaced xml processing instruction";
+    }
+    else if( XML_ERROR_UNKNOWN_ENCODING == xmlE ) {
+        Message = "unknown encoding";
+    }
+    else if( XML_ERROR_INCORRECT_ENCODING == xmlE ) {
+        Message = "incorrect encoding";
+    }
+    else if( XML_ERROR_UNCLOSED_CDATA_SECTION == xmlE ) {
+        Message = "unclosed cdata section";
+    }
+    else if( XML_ERROR_EXTERNAL_ENTITY_HANDLING == xmlE ) {
+        Message = "external entity reference";
+    }
+    else if( XML_ERROR_NOT_STANDALONE == xmlE ) {
+        Message = "not standalone";
+    }
+
+    OUString str = "[" +
+        sSystemId +
+        " line " +
+        OUString::number( nLine ) +
+        "]: " +
+        Message +
+        "error";
+
+    return str;
+}
+
+
+// starts parsing with actual parser !
+void SaxExpatParser_Impl::parse( )
+{
+    const int nBufSize = 16*1024;
+
+    int nRead   = nBufSize;
+    css::uno::Sequence< sal_Int8 > seqOut(nBufSize);
+
+    while( nRead ) {
+        nRead = getEntity().converter.readAndConvert( seqOut , nBufSize );
+
+        bool bContinue(false);
+
+        if( ! nRead ) {
+            // last call - must return OK
+            XML_Status const ret = XML_Parse( getEntity().pParser,
+                                   reinterpret_cast<const char *>(seqOut.getConstArray()),
+                                   0 ,
+                                   1 );
+            if (ret == XML_STATUS_OK) {
+                break;
+            }
+        } else {
+            bContinue = ( XML_Parse( getEntity().pParser,
+                                                reinterpret_cast<const char *>(seqOut.getConstArray()),
+                                                nRead,
+                                                0 ) != XML_STATUS_ERROR );
+        }
+
+        if( ! bContinue || bExceptionWasThrown ) {
+
+            if ( bRTExceptionWasThrown )
+                throw rtexception;
+
+            // Error during parsing !
+            XML_Error xmlE = XML_GetErrorCode( getEntity().pParser );
+            OUString sSystemId = rDocumentLocator->getSystemId();
+            sal_Int32 nLine = rDocumentLocator->getLineNumber();
+
+            SAXParseException aExcept(
+                getErrorMessage(xmlE , sSystemId, nLine) ,
+                css::uno::Reference< css::uno::XInterface >(),
+                css::uno::Any( &exception , cppu::UnoType<decltype(exception)>::get() ),
+                rDocumentLocator->getPublicId(),
+                rDocumentLocator->getSystemId(),
+                rDocumentLocator->getLineNumber(),
+                rDocumentLocator->getColumnNumber()
+                );
+
+            if( rErrorHandler.is() ) {
+
+                // error handler is set, so the handler may throw the exception
+                css::uno::Any a;
+                a <<= aExcept;
+                rErrorHandler->fatalError( a );
+            }
+
+            // Error handler has not thrown an exception, but parsing cannot go on,
+            // so an exception MUST be thrown.
+            throw aExcept;
+        } // if( ! bContinue )
+    } // while
+}
+
+
+// The C-Callbacks
+
+
+void SaxExpatParser_Impl::callbackStartElement( void *pvThis ,
+                                                const XML_Char *pwName ,
+                                                const XML_Char **awAttributes )
+{
+    SaxExpatParser_Impl *pImpl = static_cast<SaxExpatParser_Impl*>(pvThis);
+
+    if( !pImpl->rDocumentHandler.is() )
+        return;
+
+    int i = 0;
+    pImpl->rAttrList->Clear();
+
+    while( awAttributes[i] ) {
+        assert(awAttributes[i+1]);
+        pImpl->rAttrList->AddAttribute(
+            XML_CHAR_TO_OUSTRING( awAttributes[i] ) ,
+            gsCDATA,  // expat doesn't know types
+            XML_CHAR_TO_OUSTRING( awAttributes[i+1] ) );
+        i +=2;
+    }
+
+    CALL_ELEMENT_HANDLER_AND_CARE_FOR_EXCEPTIONS(
+        pImpl ,
+        rDocumentHandler->startElement( XML_CHAR_TO_OUSTRING( pwName ) ,
+                                        pImpl->rAttrList.get() ) );
+}
+
+void SaxExpatParser_Impl::callbackEndElement( void *pvThis , const XML_Char *pwName  )
+{
+    SaxExpatParser_Impl  *pImpl = static_cast<SaxExpatParser_Impl*>(pvThis);
+
+    if( pImpl->rDocumentHandler.is() ) {
+        CALL_ELEMENT_HANDLER_AND_CARE_FOR_EXCEPTIONS( pImpl,
+                rDocumentHandler->endElement( XML_CHAR_TO_OUSTRING( pwName ) ) );
+    }
+}
+
+
+void SaxExpatParser_Impl::callbackCharacters( void *pvThis , const XML_Char *s , int nLen )
+{
+    SaxExpatParser_Impl *pImpl = static_cast<SaxExpatParser_Impl*>(pvThis);
+
+    if( pImpl->rDocumentHandler.is() ) {
+        CALL_ELEMENT_HANDLER_AND_CARE_FOR_EXCEPTIONS( pImpl ,
+                rDocumentHandler->characters( XML_CHAR_N_TO_USTRING(s,nLen) ) );
+    }
+}
+
+void SaxExpatParser_Impl::callbackProcessingInstruction(    void *pvThis,
+                                                    const XML_Char *sTarget ,
+                                                    const XML_Char *sData )
+{
+    SaxExpatParser_Impl *pImpl = static_cast<SaxExpatParser_Impl*>(pvThis);
+    if( pImpl->rDocumentHandler.is() ) {
+        CALL_ELEMENT_HANDLER_AND_CARE_FOR_EXCEPTIONS(
+                    pImpl ,
+                    rDocumentHandler->processingInstruction( XML_CHAR_TO_OUSTRING( sTarget ),
+                    XML_CHAR_TO_OUSTRING( sData ) ) );
+    }
+}
+
+
+void SaxExpatParser_Impl::callbackEntityDecl(
+    void *pvThis, const XML_Char *entityName,
+    SAL_UNUSED_PARAMETER int /*is_parameter_entity*/,
+    const XML_Char *value, SAL_UNUSED_PARAMETER int /*value_length*/,
+    SAL_UNUSED_PARAMETER const XML_Char * /*base*/, const XML_Char *systemId,
+    const XML_Char *publicId, const XML_Char *notationName)
+{
+    SaxExpatParser_Impl *pImpl = static_cast<SaxExpatParser_Impl*>(pvThis);
+    if (value) { // value != 0 means internal entity
+        SAL_INFO("sax","SaxExpatParser: internal entity declaration, stopping");
+        XML_StopParser(pImpl->getEntity().pParser, XML_FALSE);
+        pImpl->exception = SAXParseException(
+            "SaxExpatParser: internal entity declaration, stopping",
+            nullptr, css::uno::Any(),
+            pImpl->rDocumentLocator->getPublicId(),
+            pImpl->rDocumentLocator->getSystemId(),
+            pImpl->rDocumentLocator->getLineNumber(),
+            pImpl->rDocumentLocator->getColumnNumber() );
+        pImpl->bExceptionWasThrown = true;
+    } else {
+        if( pImpl->rDTDHandler.is() ) {
+            CALL_ELEMENT_HANDLER_AND_CARE_FOR_EXCEPTIONS(
+                pImpl ,
+                rDTDHandler->unparsedEntityDecl(
+                    XML_CHAR_TO_OUSTRING( entityName ),
+                    XML_CHAR_TO_OUSTRING( publicId ) ,
+                    XML_CHAR_TO_OUSTRING( systemId ) ,
+                    XML_CHAR_TO_OUSTRING( notationName ) ) );
+        }
+    }
+}
+
+void SaxExpatParser_Impl::callbackNotationDecl(
+    void *pvThis, const XML_Char *notationName,
+    SAL_UNUSED_PARAMETER const XML_Char * /*base*/, const XML_Char *systemId,
+    const XML_Char *publicId)
+{
+    SaxExpatParser_Impl *pImpl = static_cast<SaxExpatParser_Impl*>(pvThis);
+    if( pImpl->rDTDHandler.is() ) {
+        CALL_ELEMENT_HANDLER_AND_CARE_FOR_EXCEPTIONS( pImpl,
+                rDTDHandler->notationDecl(  XML_CHAR_TO_OUSTRING( notationName ) ,
+                                            XML_CHAR_TO_OUSTRING( publicId ) ,
+                                            XML_CHAR_TO_OUSTRING( systemId ) ) );
+    }
+
+}
+
+
+bool SaxExpatParser_Impl::callbackExternalEntityRef(
+    XML_Parser parser, const XML_Char *context,
+    SAL_UNUSED_PARAMETER const XML_Char * /*base*/, const XML_Char *systemId,
+    const XML_Char *publicId)
+{
+    bool bOK = true;
+    SaxExpatParser_Impl *pImpl = static_cast<SaxExpatParser_Impl*>(XML_GetUserData( parser ));
+
+    struct Entity entity;
+
+    if( pImpl->rEntityResolver.is() ) {
+        try
+        {
+            entity.structSource = pImpl->rEntityResolver->resolveEntity(
+                XML_CHAR_TO_OUSTRING( publicId ) ,
+                XML_CHAR_TO_OUSTRING( systemId ) );
+        }
+        catch( const SAXParseException & e )
+        {
+            pImpl->exception = e;
+            bOK = false;
+        }
+        catch( const SAXException & e )
+        {
+            pImpl->exception = SAXParseException(
+                e.Message , e.Context , e.WrappedException ,
+                pImpl->rDocumentLocator->getPublicId(),
+                pImpl->rDocumentLocator->getSystemId(),
+                pImpl->rDocumentLocator->getLineNumber(),
+                pImpl->rDocumentLocator->getColumnNumber() );
+            bOK = false;
+        }
+    }
+
+    if( entity.structSource.aInputStream.is() ) {
+        entity.pParser = XML_ExternalEntityParserCreate( parser , context, nullptr );
+        if( ! entity.pParser )
+        {
+            return false;
+        }
+
+        entity.converter.setInputStream( entity.structSource.aInputStream );
+        auto const xmlParser = entity.pParser;
+        pImpl->pushEntity( std::move(entity) );
+        try
+        {
+            pImpl->parse();
+        }
+        catch( const SAXParseException & e )
+        {
+            pImpl->exception = e;
+            bOK = false;
+        }
+        catch( const IOException &e )
+        {
+            pImpl->exception.WrappedException <<= e;
+            bOK = false;
+        }
+        catch( const css::uno::RuntimeException &e )
+        {
+            pImpl->exception.WrappedException <<=e;
+            bOK = false;
+        }
+
+        pImpl->popEntity();
+
+        XML_ParserFree( xmlParser );
+    }
+
+    return bOK;
+}
+
+int SaxExpatParser_Impl::callbackUnknownEncoding(
+    SAL_UNUSED_PARAMETER void * /*encodingHandlerData*/,
+    SAL_UNUSED_PARAMETER const XML_Char * /*name*/,
+    SAL_UNUSED_PARAMETER XML_Encoding * /*info*/)
+{
+    return 0;
+}
+
+void SaxExpatParser_Impl::callbackDefault( void *pvThis,  const XML_Char *s,  int len)
+{
+    SaxExpatParser_Impl *pImpl = static_cast<SaxExpatParser_Impl*>(pvThis);
+
+    CALL_ELEMENT_HANDLER_AND_CARE_FOR_EXCEPTIONS(  pImpl,
+                rExtendedDocumentHandler->unknown( XML_CHAR_N_TO_USTRING( s ,len) ) );
+}
+
+void SaxExpatParser_Impl::callbackComment( void *pvThis , const XML_Char *s )
+{
+    SaxExpatParser_Impl *pImpl = static_cast<SaxExpatParser_Impl*>(pvThis);
+    CALL_ELEMENT_HANDLER_AND_CARE_FOR_EXCEPTIONS( pImpl,
+                rExtendedDocumentHandler->comment( XML_CHAR_TO_OUSTRING( s ) ) );
+}
+
+void SaxExpatParser_Impl::callbackStartCDATA( void *pvThis )
+{
+    SaxExpatParser_Impl *pImpl = static_cast<SaxExpatParser_Impl*>(pvThis);
+
+    CALL_ELEMENT_HANDLER_AND_CARE_FOR_EXCEPTIONS( pImpl, rExtendedDocumentHandler->startCDATA() );
+}
+
+
+void SaxExpatParser_Impl::callErrorHandler( SaxExpatParser_Impl *pImpl ,
+                                            const SAXParseException & e )
+{
+    try
+    {
+        if( pImpl->rErrorHandler.is() ) {
+            css::uno::Any a;
+            a <<= e;
+            pImpl->rErrorHandler->error( a );
+        }
+        else {
+            pImpl->exception = e;
+            pImpl->bExceptionWasThrown = true;
+        }
+    }
+    catch( const SAXParseException & ex ) {
+        pImpl->exception = ex;
+        pImpl->bExceptionWasThrown = true;
+    }
+    catch( const SAXException & ex ) {
+        pImpl->exception = SAXParseException(
+                                    ex.Message,
+                                    ex.Context,
+                                    ex.WrappedException,
+                                    pImpl->rDocumentLocator->getPublicId(),
+                                    pImpl->rDocumentLocator->getSystemId(),
+                                    pImpl->rDocumentLocator->getLineNumber(),
+                                    pImpl->rDocumentLocator->getColumnNumber()
+                             );
+        pImpl->bExceptionWasThrown = true;
+    }
+}
+
+void SaxExpatParser_Impl::callbackEndCDATA( void *pvThis )
+{
+    SaxExpatParser_Impl *pImpl = static_cast<SaxExpatParser_Impl*>(pvThis);
+
+    CALL_ELEMENT_HANDLER_AND_CARE_FOR_EXCEPTIONS(pImpl,rExtendedDocumentHandler->endCDATA() );
+}
+
+} // namespace
+
+extern "C" SAL_DLLPUBLIC_EXPORT css::uno::XInterface *
+com_sun_star_comp_extensions_xml_sax_ParserExpat_get_implementation(
+    css::uno::XComponentContext *,
+    css::uno::Sequence<css::uno::Any> const &)
+{
+    return cppu::acquire(new SaxExpatParser);
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sax/source/expatwrap/saxwriter.cxx b/sax/source/expatwrap/saxwriter.cxx
new file mode 100644
index 000000000..f4f4c4bae
--- /dev/null
+++ b/sax/source/expatwrap/saxwriter.cxx
@@ -0,0 +1,1418 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <string.h>
+
+#include <cassert>
+#include <set>
+#include <stack>
+
+#include <com/sun/star/io/IOException.hpp>
+#include <com/sun/star/lang/WrappedTargetRuntimeException.hpp>
+#include <com/sun/star/lang/XServiceInfo.hpp>
+#include <com/sun/star/uno/XComponentContext.hpp>
+#include <com/sun/star/util/XCloneable.hpp>
+#include <com/sun/star/xml/sax/SAXInvalidCharacterException.hpp>
+#include <com/sun/star/xml/sax/XWriter.hpp>
+
+#include <cppuhelper/exc_hlp.hxx>
+#include <cppuhelper/weak.hxx>
+#include <cppuhelper/implbase.hxx>
+#include <cppuhelper/supportsservice.hxx>
+
+#include <osl/diagnose.h>
+#include <rtl/character.hxx>
+
+using namespace ::std;
+using namespace ::osl;
+using namespace ::cppu;
+using namespace ::com::sun::star::uno;
+using namespace ::com::sun::star::lang;
+using namespace ::com::sun::star::xml::sax;
+using namespace ::com::sun::star::util;
+using namespace ::com::sun::star::io;
+
+#include <memory>
+
+#define LINEFEED 10
+#define SEQUENCESIZE 1024
+#define MAXCOLUMNCOUNT 72
+
+/******
+*
+*
+* Character conversion functions
+*
+*
+*****/
+
+namespace {
+
+enum SaxInvalidCharacterError
+{
+    SAX_NONE,
+    SAX_WARNING,
+    SAX_ERROR
+};
+
+class SaxWriterHelper
+{
+#ifdef DBG_UTIL
+public:
+    ::std::stack<OUString> m_DebugStartedElements;
+#endif
+
+private:
+    Reference< XOutputStream >  m_out;
+    Sequence < sal_Int8 >       m_Sequence;
+    sal_Int8*                   mp_Sequence;
+
+    sal_Int32                   nLastLineFeedPos; // is negative after writing a sequence
+    sal_uInt32                  nCurrentPos;
+    bool                    m_bStartElementFinished;
+
+    /// @throws SAXException
+    sal_uInt32 writeSequence();
+
+    // use only if to insert the bytes more space in the sequence is needed and
+    // so the sequence has to write out and reset rPos to 0
+    // writes sequence only on overflow, sequence could be full on the end (rPos == SEQUENCESIZE)
+    /// @throws SAXException
+    void AddBytes(sal_Int8* pTarget, sal_uInt32& rPos,
+                const sal_Int8* pBytes, sal_uInt32 nBytesCount);
+    /// @throws SAXException
+    bool convertToXML(const sal_Unicode * pStr,
+                        sal_Int32 nStrLen,
+                        bool bDoNormalization,
+                        bool bNormalizeWhitespace,
+                        sal_Int8 *pTarget,
+                        sal_uInt32& rPos);
+    /// @throws SAXException
+    void FinishStartElement();
+public:
+    explicit SaxWriterHelper(Reference< XOutputStream > const & m_TempOut)
+        : m_out(m_TempOut)
+        , m_Sequence(SEQUENCESIZE)
+        , mp_Sequence(nullptr)
+        , nLastLineFeedPos(0)
+        , nCurrentPos(0)
+        , m_bStartElementFinished(true)
+    {
+        OSL_ENSURE(SEQUENCESIZE > 50, "Sequence cache size too small");
+        mp_Sequence = m_Sequence.getArray();
+    }
+    ~SaxWriterHelper()
+    {
+        OSL_ENSURE(!nCurrentPos, "cached Sequence not written");
+        OSL_ENSURE(m_bStartElementFinished, "StartElement not completely written");
+    }
+
+    /// @throws SAXException
+    void insertIndentation(sal_uInt32 m_nLevel);
+
+// returns whether it works correct or invalid characters were in the string
+// If there are invalid characters in the string it returns sal_False.
+// Than the calling method has to throw the needed Exception.
+    /// @throws SAXException
+    bool writeString(const OUString& rWriteOutString,
+                        bool bDoNormalization,
+                        bool bNormalizeWhitespace);
+
+    sal_uInt32 GetLastColumnCount() const throw()
+        { return static_cast<sal_uInt32>(nCurrentPos - nLastLineFeedPos); }
+
+    /// @throws SAXException
+    void startDocument();
+
+// returns whether it works correct or invalid characters were in the strings
+// If there are invalid characters in one of the strings it returns sal_False.
+// Than the calling method has to throw the needed Exception.
+    /// @throws SAXException
+    SaxInvalidCharacterError startElement(const OUString& rName, const Reference< XAttributeList >& xAttribs);
+    /// @throws SAXException
+    bool FinishEmptyElement();
+
+// returns whether it works correct or invalid characters were in the string
+// If there are invalid characters in the string it returns sal_False.
+// Than the calling method has to throw the needed Exception.
+    /// @throws SAXException
+    bool endElement(const OUString& rName);
+    /// @throws SAXException
+    void endDocument();
+
+// returns whether it works correct or invalid characters were in the strings
+// If there are invalid characters in the string it returns sal_False.
+// Than the calling method has to throw the needed Exception.
+    /// @throws SAXException
+    bool processingInstruction(const OUString& rTarget, const OUString& rData);
+    /// @throws SAXException
+    void startCDATA();
+    /// @throws SAXException
+    void endCDATA();
+
+// returns whether it works correct or invalid characters were in the strings
+// If there are invalid characters in the string it returns sal_False.
+// Than the calling method has to throw the needed Exception.
+    /// @throws SAXException
+    bool comment(const OUString& rComment);
+
+    /// @throws SAXException
+    void clearBuffer();
+};
+
+const bool g_bValidCharsBelow32[32] =
+{
+//  0     1     2     3     4     5     6     7
+    false,false,false,false,false,false,false,false,  //0
+    false,true, true, false,false,true, false,false,  //8
+    false,false,false,false,false,false,false,false,  //16
+    false,false,false,false,false,false,false,false
+};
+
+bool IsInvalidChar(const sal_Unicode aChar)
+{
+    bool bRet(false);
+    // check first for the most common characters
+    if( aChar < 32 || aChar >= 0xd800 )
+        bRet = ( (aChar < 32 && ! g_bValidCharsBelow32[aChar]) ||
+            aChar == 0xffff ||
+            aChar == 0xfffe );
+    return bRet;
+}
+
+/********
+* write through to the output stream
+*
+*****/
+sal_uInt32 SaxWriterHelper::writeSequence()
+{
+    try
+    {
+        m_out->writeBytes( m_Sequence );
+    }
+    catch (const IOException &)
+    {
+        css::uno::Any anyEx = cppu::getCaughtException();
+        throw SAXException(
+            "IO exception during writing",
+            Reference< XInterface > (),
+            anyEx );
+    }
+    nLastLineFeedPos -= SEQUENCESIZE;
+    return 0;
+}
+
+void SaxWriterHelper::AddBytes(sal_Int8* pTarget, sal_uInt32& rPos,
+                const sal_Int8* pBytes, sal_uInt32 nBytesCount)
+{
+    OSL_ENSURE((rPos + nBytesCount) > SEQUENCESIZE, "wrong use of AddBytesMethod");
+    sal_uInt32 nCount(SEQUENCESIZE - rPos);
+    memcpy( &(pTarget[rPos]) , pBytes,  nCount);
+
+    OSL_ENSURE(rPos + nCount == SEQUENCESIZE, "the position should be the at the end");
+
+    rPos = writeSequence();
+    sal_uInt32 nRestCount(nBytesCount - nCount);
+    if ((rPos + nRestCount) <= SEQUENCESIZE)
+    {
+        memcpy( &(pTarget[rPos]), &pBytes[nCount], nRestCount);
+        rPos += nRestCount;
+    }
+    else
+        AddBytes(pTarget, rPos, &pBytes[nCount], nRestCount);
+}
+
+/** Converts a UTF-16 string to UTF-8 and does XML normalization
+
+    @param pTarget
+           Pointer to a piece of memory, to where the output should be written. The caller
+           must call calcXMLByteLength on the same string, to ensure,
+           that there is enough memory for converting.
+ */
+bool SaxWriterHelper::convertToXML( const sal_Unicode * pStr,
+                        sal_Int32 nStrLen,
+                        bool bDoNormalization,
+                        bool bNormalizeWhitespace,
+                        sal_Int8 *pTarget,
+                        sal_uInt32& rPos )
+{
+    bool bRet(true);
+    sal_uInt32 nSurrogate = 0;
+
+    for( sal_Int32 i = 0 ; i < nStrLen ; i ++ )
+    {
+        sal_uInt16 c = pStr[i];
+        if (IsInvalidChar(c))
+            bRet = false;
+        else if( (c >= 0x0001) && (c <= 0x007F) )
+        {
+            if( bDoNormalization )
+            {
+                switch( c )
+                {
+                    case '&':  // resemble to &amp;
+                    {
+                        if ((rPos + 5) > SEQUENCESIZE)
+                            AddBytes(pTarget, rPos, reinterpret_cast<sal_Int8 const *>("&amp;"), 5);
+                        else
+                        {
+                            memcpy( &(pTarget[rPos]) , "&amp;", 5 );
+                            rPos += 5;
+                        }
+                    }
+                    break;
+                    case '<':
+                    {
+                        if ((rPos + 4) > SEQUENCESIZE)
+                            AddBytes(pTarget, rPos, reinterpret_cast<sal_Int8 const *>("&lt;"), 4);
+                        else
+                        {
+                            memcpy( &(pTarget[rPos]) , "&lt;" , 4 );
+                            rPos += 4;        // &lt;
+                        }
+                    }
+                    break;
+                    case '>':
+                    {
+                        if ((rPos + 4) > SEQUENCESIZE)
+                            AddBytes(pTarget, rPos, reinterpret_cast<sal_Int8 const *>("&gt;"), 4);
+                        else
+                        {
+                            memcpy( &(pTarget[rPos]) , "&gt;" , 4 );
+                            rPos += 4;        // &gt;
+                        }
+                    }
+                    break;
+                    case 39:                 // 39 == '''
+                    {
+                        if ((rPos + 6) > SEQUENCESIZE)
+                            AddBytes(pTarget, rPos, reinterpret_cast<sal_Int8 const *>("&apos;"), 6);
+                        else
+                        {
+                            memcpy( &(pTarget[rPos]) , "&apos;" , 6 );
+                            rPos += 6;        // &apos;
+                        }
+                    }
+                    break;
+                    case '"':
+                    {
+                        if ((rPos + 6) > SEQUENCESIZE)
+                            AddBytes(pTarget, rPos, reinterpret_cast<sal_Int8 const *>("&quot;"), 6);
+                        else
+                        {
+                            memcpy( &(pTarget[rPos]) , "&quot;" , 6 );
+                            rPos += 6;        // &quot;
+                        }
+                    }
+                    break;
+                    case 13:
+                    {
+                        if ((rPos + 6) > SEQUENCESIZE)
+                            AddBytes(pTarget, rPos, reinterpret_cast<sal_Int8 const *>("&#x0d;"), 6);
+                        else
+                        {
+                            memcpy( &(pTarget[rPos]) , "&#x0d;" , 6 );
+                            rPos += 6;
+                        }
+                    }
+                    break;
+                    case LINEFEED:
+                    {
+                        if( bNormalizeWhitespace )
+                        {
+                            if ((rPos + 6) > SEQUENCESIZE)
+                                AddBytes(pTarget, rPos, reinterpret_cast<sal_Int8 const *>("&#x0a;"), 6);
+                            else
+                            {
+                                memcpy( &(pTarget[rPos]) , "&#x0a;" , 6 );
+                                rPos += 6;
+                            }
+                        }
+                        else
+                        {
+                            pTarget[rPos] = LINEFEED;
+                            nLastLineFeedPos = rPos;
+                            rPos ++;
+                        }
+                    }
+                    break;
+                    case 9:
+                    {
+                        if( bNormalizeWhitespace )
+                        {
+                            if ((rPos + 6) > SEQUENCESIZE)
+                                AddBytes(pTarget, rPos, reinterpret_cast<sal_Int8 const *>("&#x09;"), 6);
+                            else
+                            {
+                                memcpy( &(pTarget[rPos]) , "&#x09;" , 6 );
+                                rPos += 6;
+                            }
+                        }
+                        else
+                        {
+                            pTarget[rPos] = 9;
+                            rPos ++;
+                        }
+                    }
+                    break;
+                    default:
+                    {
+                        pTarget[rPos] = static_cast<sal_Int8>(c);
+                        rPos ++;
+                    }
+                    break;
+                }
+            }
+            else
+            {
+                pTarget[rPos] = static_cast<sal_Int8>(c);
+                if (static_cast<sal_Int8>(c) == LINEFEED)
+                    nLastLineFeedPos = rPos;
+                rPos ++;
+            }
+        }
+        else if( c >= 0xd800 && c < 0xdc00  )
+        {
+            // 1. surrogate: save (until 2. surrogate)
+            OSL_ENSURE( nSurrogate == 0, "left-over Unicode surrogate" );
+            nSurrogate = ( ( c & 0x03ff ) + 0x0040 );
+        }
+        else if( c >= 0xdc00 && c < 0xe000 )
+        {
+            // 2. surrogate: write as UTF-8
+            OSL_ENSURE( nSurrogate != 0, "lone 2nd Unicode surrogate" );
+
+            nSurrogate = ( nSurrogate << 10 ) | ( c & 0x03ff );
+            if( rtl::isUnicodeScalarValue(nSurrogate) && nSurrogate >= 0x00010000 )
+            {
+                sal_Int8 aBytes[] = { sal_Int8(0xF0 | ((nSurrogate >> 18) & 0x0F)),
+                                      sal_Int8(0x80 | ((nSurrogate >> 12) & 0x3F)),
+                                      sal_Int8(0x80 | ((nSurrogate >>  6) & 0x3F)),
+                                      sal_Int8(0x80 | ((nSurrogate >>  0) & 0x3F)) };
+                if ((rPos + 4) > SEQUENCESIZE)
+                    AddBytes(pTarget, rPos, aBytes, 4);
+                else
+                {
+                    pTarget[rPos] = aBytes[0];
+                    rPos ++;
+                    pTarget[rPos] = aBytes[1];
+                    rPos ++;
+                    pTarget[rPos] = aBytes[2];
+                    rPos ++;
+                    pTarget[rPos] = aBytes[3];
+                    rPos ++;
+                }
+            }
+            else
+            {
+                OSL_FAIL( "illegal Unicode character" );
+                bRet = false;
+            }
+
+            // reset surrogate
+            nSurrogate = 0;
+        }
+        else if( c > 0x07FF )
+        {
+            sal_Int8 aBytes[] = { sal_Int8(0xE0 | ((c >> 12) & 0x0F)),
+                                  sal_Int8(0x80 | ((c >>  6) & 0x3F)),
+                                  sal_Int8(0x80 | ((c >>  0) & 0x3F)) };
+            if ((rPos + 3) > SEQUENCESIZE)
+                AddBytes(pTarget, rPos, aBytes, 3);
+            else
+            {
+                pTarget[rPos] = aBytes[0];
+                rPos ++;
+                pTarget[rPos] = aBytes[1];
+                rPos ++;
+                pTarget[rPos] = aBytes[2];
+                rPos ++;
+            }
+        }
+        else
+        {
+            sal_Int8 aBytes[] = { sal_Int8(0xC0 | ((c >>  6) & 0x1F)),
+                                sal_Int8(0x80 | ((c >>  0) & 0x3F)) };
+            if ((rPos + 2) > SEQUENCESIZE)
+                AddBytes(pTarget, rPos, aBytes, 2);
+            else
+            {
+                pTarget[rPos] = aBytes[0];
+                rPos ++;
+                pTarget[rPos] = aBytes[1];
+                rPos ++;
+            }
+        }
+        OSL_ENSURE(rPos <= SEQUENCESIZE, "not reset current position");
+        if (rPos == SEQUENCESIZE)
+            rPos = writeSequence();
+
+        // reset left-over surrogate
+        if( ( nSurrogate != 0 ) && !( c >= 0xd800 && c < 0xdc00 ) )
+        {
+            OSL_ENSURE( nSurrogate != 0, "left-over Unicode surrogate" );
+            nSurrogate = 0;
+            bRet = false;
+        }
+    }
+    return bRet;
+}
+
+void SaxWriterHelper::FinishStartElement()
+{
+    if (!m_bStartElementFinished)
+    {
+        mp_Sequence[nCurrentPos] = '>';
+        nCurrentPos++;
+        if (nCurrentPos == SEQUENCESIZE)
+            nCurrentPos = writeSequence();
+        m_bStartElementFinished = true;
+    }
+}
+
+void SaxWriterHelper::insertIndentation(sal_uInt32 m_nLevel)
+{
+    FinishStartElement();
+    if (m_nLevel > 0)
+    {
+        if ((nCurrentPos + m_nLevel + 1) <= SEQUENCESIZE)
+        {
+            mp_Sequence[nCurrentPos] = LINEFEED;
+            nLastLineFeedPos = nCurrentPos;
+            nCurrentPos++;
+            memset( &(mp_Sequence[nCurrentPos]) , 32 , m_nLevel );
+            nCurrentPos += m_nLevel;
+            if (nCurrentPos == SEQUENCESIZE)
+                nCurrentPos = writeSequence();
+        }
+        else
+        {
+            sal_uInt32 nCount(m_nLevel + 1);
+            std::unique_ptr<sal_Int8[]> pBytes(new sal_Int8[nCount]);
+            pBytes[0] = LINEFEED;
+            memset( &(pBytes[1]), 32, m_nLevel );
+            AddBytes(mp_Sequence, nCurrentPos, pBytes.get(), nCount);
+            pBytes.reset();
+            nLastLineFeedPos = nCurrentPos - nCount;
+            if (nCurrentPos == SEQUENCESIZE)
+                nCurrentPos = writeSequence();
+        }
+    }
+    else
+    {
+        mp_Sequence[nCurrentPos] = LINEFEED;
+        nLastLineFeedPos = nCurrentPos;
+        nCurrentPos++;
+        if (nCurrentPos == SEQUENCESIZE)
+            nCurrentPos = writeSequence();
+    }
+}
+
+bool SaxWriterHelper::writeString( const OUString& rWriteOutString,
+                        bool bDoNormalization,
+                        bool bNormalizeWhitespace )
+{
+    FinishStartElement();
+    return convertToXML(rWriteOutString.getStr(),
+                    rWriteOutString.getLength(),
+                    bDoNormalization,
+                    bNormalizeWhitespace,
+                    mp_Sequence,
+                    nCurrentPos);
+}
+
+void SaxWriterHelper::startDocument()
+{
+    const char pc[] = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>";
+    const int nLen = strlen( pc );
+    if ((nCurrentPos + nLen) <= SEQUENCESIZE)
+    {
+        memcpy( mp_Sequence, pc , nLen );
+        nCurrentPos += nLen;
+    }
+    else
+    {
+        AddBytes(mp_Sequence, nCurrentPos, reinterpret_cast<sal_Int8 const *>(pc), nLen);
+    }
+    OSL_ENSURE(nCurrentPos <= SEQUENCESIZE, "not reset current position");
+    if (nCurrentPos == SEQUENCESIZE)
+        nCurrentPos = writeSequence();
+    mp_Sequence[nCurrentPos] = LINEFEED;
+    nCurrentPos++;
+    if (nCurrentPos == SEQUENCESIZE)
+        nCurrentPos = writeSequence();
+}
+
+#ifndef NDEBUG
+bool inrange(sal_Unicode c, sal_Unicode start, sal_Unicode end)
+{
+    return c >= start && c <= end;
+}
+#endif
+
+void CheckValidName(OUString const& rName)
+{
+#ifdef NDEBUG
+    (void) rName;
+#else
+    assert(!rName.isEmpty());
+    bool hasColon(false);
+    for (sal_Int32 i = 0; i < rName.getLength(); ++i)
+    {
+        auto const c(rName[i]);
+        if (c == ':')
+        {
+            // see https://www.w3.org/TR/REC-xml-names/#ns-qualnames
+            assert(!hasColon && "only one colon allowed");
+            hasColon = true;
+        }
+        else if (!rtl::isAsciiAlphanumeric(c) && c != '_' && c != '-' && c != '.' &&
+                 !inrange(c, 0x00C0, 0x00D6) && !inrange(c, 0x00D8, 0x00F6) &&
+                 !inrange(c, 0x00F8, 0x02FF) && !inrange(c, 0x0370, 0x037D) &&
+                 !inrange(c, 0x037F, 0x1FFF) && !inrange(c, 0x200C, 0x200D) &&
+                 !inrange(c, 0x2070, 0x218F) && !inrange(c, 0x2C00, 0x2FEF) &&
+                 !inrange(c, 0x3001, 0xD7FF) && !inrange(c, 0xF900, 0xFDCF) &&
+                 !inrange(c, 0xFDF0, 0xFFFD) && c != 0x00B7 &&
+                 !inrange(c, 0x0300, 0x036F) && !inrange(c, 0x203F, 0x2040))
+        {
+            // https://www.w3.org/TR/xml11/#NT-NameChar
+            // (currently we don't warn about invalid start chars)
+            assert(!"unexpected character in attribute name");
+        }
+    }
+#endif
+}
+
+SaxInvalidCharacterError SaxWriterHelper::startElement(const OUString& rName, const Reference< XAttributeList >& xAttribs)
+{
+    FinishStartElement();
+
+#ifdef DBG_UTIL
+    m_DebugStartedElements.push(rName);
+    ::std::set<OUString> DebugAttributes;
+#endif
+
+    mp_Sequence[nCurrentPos] = '<';
+    nCurrentPos++;
+    if (nCurrentPos == SEQUENCESIZE)
+        nCurrentPos = writeSequence();
+
+    SaxInvalidCharacterError eRet(SAX_NONE);
+    CheckValidName(rName);
+    if (!writeString(rName, false, false))
+        eRet = SAX_ERROR;
+
+    sal_Int16 nAttribCount = xAttribs.is() ? xAttribs->getLength() : 0;
+    for(sal_Int16 i = 0 ; i < nAttribCount ; i++ )
+    {
+        mp_Sequence[nCurrentPos] = ' ';
+        nCurrentPos++;
+        if (nCurrentPos == SEQUENCESIZE)
+            nCurrentPos = writeSequence();
+
+        OUString const& rAttrName(xAttribs->getNameByIndex(i));
+#ifdef DBG_UTIL
+        // Well-formedness constraint: Unique Att Spec
+        assert(DebugAttributes.find(rAttrName) == DebugAttributes.end());
+        DebugAttributes.insert(rAttrName);
+#endif
+        CheckValidName(rAttrName);
+        if (!writeString(rAttrName, false, false))
+            eRet = SAX_ERROR;
+
+        mp_Sequence[nCurrentPos] = '=';
+        nCurrentPos++;
+        if (nCurrentPos == SEQUENCESIZE)
+            nCurrentPos = writeSequence();
+        mp_Sequence[nCurrentPos] = '"';
+        nCurrentPos++;
+        if (nCurrentPos == SEQUENCESIZE)
+            nCurrentPos = writeSequence();
+
+        if (!writeString(xAttribs->getValueByIndex( i ), true, true) &&
+            eRet != SAX_ERROR)
+            eRet = SAX_WARNING;
+
+        mp_Sequence[nCurrentPos] = '"';
+        nCurrentPos++;
+        if (nCurrentPos == SEQUENCESIZE)
+            nCurrentPos = writeSequence();
+    }
+
+    m_bStartElementFinished = false;    // because the '>' character is not added,
+                                            // because it is possible, that the "/>"
+                                            // characters have to add
+    return eRet;
+}
+
+bool SaxWriterHelper::FinishEmptyElement()
+{
+    if (m_bStartElementFinished)
+        return false;
+
+    mp_Sequence[nCurrentPos] = '/';
+    nCurrentPos++;
+    if (nCurrentPos == SEQUENCESIZE)
+        nCurrentPos = writeSequence();
+    mp_Sequence[nCurrentPos] = '>';
+    nCurrentPos++;
+    if (nCurrentPos == SEQUENCESIZE)
+        nCurrentPos = writeSequence();
+
+    m_bStartElementFinished = true;
+
+    return true;
+}
+
+bool SaxWriterHelper::endElement(const OUString& rName)
+{
+    FinishStartElement();
+
+    mp_Sequence[nCurrentPos] = '<';
+    nCurrentPos++;
+    if (nCurrentPos == SEQUENCESIZE)
+        nCurrentPos = writeSequence();
+    mp_Sequence[nCurrentPos] = '/';
+    nCurrentPos++;
+    if (nCurrentPos == SEQUENCESIZE)
+        nCurrentPos = writeSequence();
+
+    CheckValidName(rName);
+    bool bRet(writeString( rName, false, false));
+
+    mp_Sequence[nCurrentPos] = '>';
+    nCurrentPos++;
+    if (nCurrentPos == SEQUENCESIZE)
+        nCurrentPos = writeSequence();
+
+    return bRet;
+}
+
+void SaxWriterHelper::endDocument()
+{
+    if (nCurrentPos > 0)
+    {
+        m_Sequence.realloc(nCurrentPos);
+        nCurrentPos = writeSequence();
+        //m_Sequence.realloc(SEQUENCESIZE);
+    }
+}
+
+void SaxWriterHelper::clearBuffer()
+{
+    FinishStartElement();
+    if (nCurrentPos > 0)
+    {
+        m_Sequence.realloc(nCurrentPos);
+        nCurrentPos = writeSequence();
+        m_Sequence.realloc(SEQUENCESIZE);
+        // Be sure to update the array pointer after the reallocation.
+        mp_Sequence = m_Sequence.getArray();
+    }
+}
+
+bool SaxWriterHelper::processingInstruction(const OUString& rTarget, const OUString& rData)
+{
+    FinishStartElement();
+    mp_Sequence[nCurrentPos] = '<';
+    nCurrentPos++;
+    if (nCurrentPos == SEQUENCESIZE)
+        nCurrentPos = writeSequence();
+    mp_Sequence[nCurrentPos] = '?';
+    nCurrentPos++;
+    if (nCurrentPos == SEQUENCESIZE)
+        nCurrentPos = writeSequence();
+
+    bool bRet(writeString( rTarget, false, false ));
+
+    mp_Sequence[nCurrentPos] = ' ';
+    nCurrentPos++;
+    if (nCurrentPos == SEQUENCESIZE)
+        nCurrentPos = writeSequence();
+
+    if (!writeString( rData, false, false ))
+        bRet = false;
+
+    mp_Sequence[nCurrentPos] = '?';
+    nCurrentPos++;
+    if (nCurrentPos == SEQUENCESIZE)
+        nCurrentPos = writeSequence();
+    mp_Sequence[nCurrentPos] = '>';
+    nCurrentPos++;
+    if (nCurrentPos == SEQUENCESIZE)
+        nCurrentPos = writeSequence();
+
+    return bRet;
+}
+
+void SaxWriterHelper::startCDATA()
+{
+    FinishStartElement();
+    if ((nCurrentPos + 9) <= SEQUENCESIZE)
+    {
+        memcpy( &(mp_Sequence[nCurrentPos]), "<![CDATA[" , 9 );
+        nCurrentPos += 9;
+    }
+    else
+        AddBytes(mp_Sequence, nCurrentPos, reinterpret_cast<sal_Int8 const *>("<![CDATA["), 9);
+    if (nCurrentPos == SEQUENCESIZE)
+        nCurrentPos = writeSequence();
+}
+
+void SaxWriterHelper::endCDATA()
+{
+    FinishStartElement();
+    if ((nCurrentPos + 3) <= SEQUENCESIZE)
+    {
+        memcpy( &(mp_Sequence[nCurrentPos]), "]]>" , 3 );
+        nCurrentPos += 3;
+    }
+    else
+        AddBytes(mp_Sequence, nCurrentPos, reinterpret_cast<sal_Int8 const *>("]]>"), 3);
+    if (nCurrentPos == SEQUENCESIZE)
+        nCurrentPos = writeSequence();
+}
+
+bool SaxWriterHelper::comment(const OUString& rComment)
+{
+    FinishStartElement();
+    mp_Sequence[nCurrentPos] = '<';
+    nCurrentPos++;
+    if (nCurrentPos == SEQUENCESIZE)
+        nCurrentPos = writeSequence();
+    mp_Sequence[nCurrentPos] = '!';
+    nCurrentPos++;
+    if (nCurrentPos == SEQUENCESIZE)
+        nCurrentPos = writeSequence();
+    mp_Sequence[nCurrentPos] = '-';
+    nCurrentPos++;
+    if (nCurrentPos == SEQUENCESIZE)
+        nCurrentPos = writeSequence();
+    mp_Sequence[nCurrentPos] = '-';
+    nCurrentPos++;
+    if (nCurrentPos == SEQUENCESIZE)
+        nCurrentPos = writeSequence();
+
+    bool bRet(writeString( rComment, false, false));
+
+    mp_Sequence[nCurrentPos] = '-';
+    nCurrentPos++;
+    if (nCurrentPos == SEQUENCESIZE)
+        nCurrentPos = writeSequence();
+    mp_Sequence[nCurrentPos] = '-';
+    nCurrentPos++;
+    if (nCurrentPos == SEQUENCESIZE)
+        nCurrentPos = writeSequence();
+    mp_Sequence[nCurrentPos] = '>';
+    nCurrentPos++;
+    if (nCurrentPos == SEQUENCESIZE)
+        nCurrentPos = writeSequence();
+
+    return bRet;
+}
+
+sal_Int32 calcXMLByteLength( const OUString& rStr,
+                                    bool bDoNormalization,
+                                    bool bNormalizeWhitespace )
+{
+    sal_Int32 nOutputLength = 0;
+    sal_uInt32 nSurrogate = 0;
+
+    const sal_Unicode *pStr = rStr.getStr();
+    sal_Int32 nStrLen = rStr.getLength();
+    for( sal_Int32 i = 0 ; i < nStrLen ; i++ )
+    {
+        sal_uInt16 c = pStr[i];
+        if( !IsInvalidChar(c) && (c >= 0x0001) && (c <= 0x007F) )
+        {
+            if( bDoNormalization )
+            {
+                switch( c )
+                {
+                case '&':       // resemble to &amp;
+                    nOutputLength +=5;
+                    break;
+                case '<':       // &lt;
+                case '>':       // &gt;
+                    nOutputLength +=4;
+                    break;
+                case 39:        // 39 == ''', &apos;
+                case '"':       // &quot;
+                case 13:        // &#x0d;
+                    nOutputLength += 6;
+                    break;
+
+                case 10:        // &#x0a;
+                case 9:         // &#x09;
+                    if( bNormalizeWhitespace )
+                    {
+                        nOutputLength += 6;
+                    }
+                    else
+                    {
+                        nOutputLength ++;
+                    }
+                    break;
+                default:
+                    nOutputLength ++;
+                }
+            }
+            else
+            {
+                nOutputLength ++;
+            }
+        }
+        else if( c >= 0xd800 && c < 0xdc00  )
+        {
+            // save surrogate
+            nSurrogate = ( ( c & 0x03ff ) + 0x0040 );
+        }
+        else if( c >= 0xdc00 && c < 0xe000 )
+        {
+            // 2. surrogate: write as UTF-8 (if range is OK
+            nSurrogate = ( nSurrogate << 10 ) | ( c & 0x03ff );
+            if( rtl::isUnicodeScalarValue(nSurrogate) && nSurrogate >= 0x00010000 )
+                nOutputLength += 4;
+            nSurrogate = 0;
+        }
+        else if( c > 0x07FF )
+        {
+            nOutputLength += 3;
+        }
+        else
+        {
+            nOutputLength += 2;
+        }
+
+        // surrogate processing
+        if( ( nSurrogate != 0 ) && !( c >= 0xd800 && c < 0xdc00 ) )
+            nSurrogate = 0;
+    }
+
+    return nOutputLength;
+}
+
+/** returns position of first ascii 10 within the string, -1 when no 10 in string.
+ */
+sal_Int32 getFirstLineBreak( const OUString & str ) throw ()
+{
+    const sal_Unicode *pSource = str.getStr();
+    sal_Int32 nLen  = str.getLength();
+
+    for( int n = 0; n < nLen ; n ++ )
+    {
+        if( LINEFEED == pSource[n] ) {
+            return n;
+        }
+    }
+    return -1;
+}
+
+class SAXWriter :
+    public WeakImplHelper<
+            XWriter,
+            XServiceInfo >
+{
+public:
+    SAXWriter()
+        : m_bDocStarted(false)
+        , m_bIsCDATA(false)
+        , m_bForceLineBreak(false)
+        , m_bAllowLineBreak(false)
+        , m_nLevel(0)
+    {
+    }
+
+public: // XActiveDataSource
+    virtual void SAL_CALL setOutputStream(const Reference< XOutputStream > & aStream) override
+    {
+        try
+        {
+            // temporary: set same stream again to clear buffer
+            if ( m_out == aStream && m_pSaxWriterHelper && m_bDocStarted )
+                m_pSaxWriterHelper->clearBuffer();
+            else
+            {
+                m_out = aStream;
+                m_pSaxWriterHelper.reset( new SaxWriterHelper(m_out) );
+                m_bDocStarted = false;
+                m_nLevel = 0;
+                m_bIsCDATA = false;
+            }
+        }
+        catch (const SAXException& e)
+        {
+            throw css::lang::WrappedTargetRuntimeException(
+                   e.Message,
+                   static_cast < OWeakObject * > ( this ),
+                   e.WrappedException);
+        }
+    }
+    virtual Reference< XOutputStream >  SAL_CALL getOutputStream() override
+    {
+        return m_out;
+    }
+
+public: // XDocumentHandler
+    virtual void SAL_CALL startDocument() override;
+
+    virtual void SAL_CALL endDocument() override;
+
+    virtual void SAL_CALL startElement(const OUString& aName,
+                                       const Reference< XAttributeList > & xAttribs) override;
+
+    virtual void SAL_CALL endElement(const OUString& aName) override;
+
+    virtual void SAL_CALL characters(const OUString& aChars) override;
+
+    virtual void SAL_CALL ignorableWhitespace(const OUString& aWhitespaces) override;
+    virtual void SAL_CALL processingInstruction(const OUString& aTarget,
+                                                const OUString& aData) override;
+    virtual void SAL_CALL setDocumentLocator(const Reference< XLocator > & xLocator) override;
+
+public: // XExtendedDocumentHandler
+    virtual void SAL_CALL startCDATA() override;
+    virtual void SAL_CALL endCDATA() override;
+    virtual void SAL_CALL comment(const OUString& sComment) override;
+    virtual void SAL_CALL unknown(const OUString& sString) override;
+    virtual void SAL_CALL allowLineBreak() override;
+
+public: // XServiceInfo
+    OUString                     SAL_CALL getImplementationName() override;
+    Sequence< OUString >         SAL_CALL getSupportedServiceNames() override;
+    sal_Bool                    SAL_CALL supportsService(const OUString& ServiceName) override;
+
+private:
+    sal_Int32 getIndentPrefixLength( sal_Int32 nFirstLineBreakOccurrence ) throw();
+
+    Reference< XOutputStream >        m_out;
+    std::unique_ptr<SaxWriterHelper>  m_pSaxWriterHelper;
+
+    // Status information
+    bool m_bDocStarted : 1;
+    bool m_bIsCDATA : 1;
+    bool m_bForceLineBreak : 1;
+    bool m_bAllowLineBreak : 1;
+    sal_Int32 m_nLevel;
+};
+
+sal_Int32 SAXWriter::getIndentPrefixLength( sal_Int32 nFirstLineBreakOccurrence ) throw()
+{
+    sal_Int32 nLength =-1;
+    if (m_pSaxWriterHelper)
+    {
+        if ( m_bForceLineBreak ||
+            (m_bAllowLineBreak &&
+            ((nFirstLineBreakOccurrence + m_pSaxWriterHelper->GetLastColumnCount()) > MAXCOLUMNCOUNT)) )
+            nLength = m_nLevel;
+    }
+    m_bForceLineBreak = false;
+    m_bAllowLineBreak = false;
+    return nLength;
+}
+
+bool isFirstCharWhitespace( const sal_Unicode *p ) throw()
+{
+    return *p == ' ';
+}
+
+// XServiceInfo
+OUString SAXWriter::getImplementationName()
+{
+    return "com.sun.star.extensions.xml.sax.Writer";
+}
+
+// XServiceInfo
+sal_Bool SAXWriter::supportsService(const OUString& ServiceName)
+{
+    return cppu::supportsService(this, ServiceName);
+}
+
+// XServiceInfo
+Sequence< OUString > SAXWriter::getSupportedServiceNames()
+{
+    return { "com.sun.star.xml.sax.Writer" };
+}
+
+void SAXWriter::startDocument()
+{
+    if( m_bDocStarted || ! m_out.is() || !m_pSaxWriterHelper ) {
+        throw SAXException();
+    }
+    m_bDocStarted = true;
+    m_pSaxWriterHelper->startDocument();
+}
+
+
+void SAXWriter::endDocument()
+{
+    if( ! m_bDocStarted )
+    {
+        throw SAXException(
+            "endDocument called before startDocument",
+            Reference< XInterface >() , Any() );
+    }
+    if( m_nLevel ) {
+        throw SAXException(
+            "unexpected end of document",
+            Reference< XInterface >() , Any() );
+    }
+    m_pSaxWriterHelper->endDocument();
+    try
+    {
+        m_out->closeOutput();
+    }
+    catch (const IOException &)
+    {
+        css::uno::Any anyEx = cppu::getCaughtException();
+        throw SAXException(
+            "IO exception during closing the IO Stream",
+            Reference< XInterface > (),
+            anyEx );
+    }
+}
+
+
+void SAXWriter::startElement(const OUString& aName, const Reference< XAttributeList >& xAttribs)
+{
+    if( ! m_bDocStarted )
+    {
+        SAXException except;
+        except.Message = "startElement called before startDocument";
+        throw except;
+    }
+    if( m_bIsCDATA )
+    {
+        SAXException except;
+        except.Message =  "startElement call not allowed with CDATA sections";
+        throw except;
+    }
+
+    sal_Int32 nLength(0);
+    if (m_bAllowLineBreak)
+    {
+        sal_Int32 nAttribCount = xAttribs.is() ? xAttribs->getLength() : 0;
+
+        nLength ++; // "<"
+        nLength += calcXMLByteLength( aName, false, false ); // the tag name
+
+        sal_Int16 n;
+        for( n = 0 ; n < static_cast<sal_Int16>(nAttribCount) ; n ++ ) {
+            nLength ++; // " "
+            OUString tmp =  xAttribs->getNameByIndex( n );
+
+            nLength += calcXMLByteLength( tmp, false, false );
+
+            nLength += 2; // ="
+
+            tmp = xAttribs->getValueByIndex( n );
+
+            nLength += calcXMLByteLength( tmp, true, true );
+
+            nLength += 1; // "
+        }
+
+        nLength ++;  // '>'
+    }
+
+    // Is there a new indentation necessary ?
+    sal_Int32 nPrefix(getIndentPrefixLength( nLength ));
+
+    // write into sequence
+    if( nPrefix >= 0 )
+        m_pSaxWriterHelper->insertIndentation( nPrefix );
+
+    SaxInvalidCharacterError eRet(m_pSaxWriterHelper->startElement(aName, xAttribs));
+
+    m_nLevel++;
+
+    if (eRet == SAX_WARNING)
+    {
+        SAXInvalidCharacterException except;
+        except.Message = "Invalid character during XML-Export in an attribute value";
+        throw except;
+    }
+    else if (eRet == SAX_ERROR)
+    {
+        SAXException except;
+        except.Message = "Invalid character during XML-Export";
+        throw except;
+    }
+}
+
+void SAXWriter::endElement(const OUString& aName)
+{
+    if( ! m_bDocStarted ) {
+        throw SAXException ();
+    }
+    m_nLevel --;
+
+    if( m_nLevel < 0 ) {
+        throw SAXException();
+    }
+    bool bRet(true);
+
+    // check here because Helper's endElement is not always called
+#ifdef DBG_UTIL
+    assert(!m_pSaxWriterHelper->m_DebugStartedElements.empty());
+    // Well-formedness constraint: Element Type Match
+    assert(aName == m_pSaxWriterHelper->m_DebugStartedElements.top());
+    m_pSaxWriterHelper->m_DebugStartedElements.pop();
+#endif
+
+    if( m_pSaxWriterHelper->FinishEmptyElement() )
+        m_bForceLineBreak = false;
+    else
+    {
+        // only ascii chars allowed
+        sal_Int32 nLength(0);
+        if (m_bAllowLineBreak)
+            nLength = 3 + calcXMLByteLength( aName, false, false );
+        sal_Int32 nPrefix = getIndentPrefixLength( nLength );
+
+        if( nPrefix >= 0 )
+            m_pSaxWriterHelper->insertIndentation( nPrefix );
+
+        bRet = m_pSaxWriterHelper->endElement(aName);
+    }
+
+    if (!bRet)
+    {
+        SAXException except;
+        except.Message = "Invalid character during XML-Export";
+        throw except;
+    }
+}
+
+void SAXWriter::characters(const OUString& aChars)
+{
+    if( ! m_bDocStarted )
+    {
+        SAXException except;
+        except.Message = "characters method called before startDocument";
+        throw except;
+    }
+
+    bool bThrowException(false);
+    if( !aChars.isEmpty() )
+    {
+        if( m_bIsCDATA )
+            bThrowException = !m_pSaxWriterHelper->writeString( aChars, false, false );
+        else
+        {
+            // Note : nFirstLineBreakOccurrence is not exact, because we don't know, how
+            //        many 2 and 3 byte chars are inbetween. However this whole stuff
+            //        is eitherway for pretty printing only, so it does not need to be exact.
+            sal_Int32 nLength(0);
+            sal_Int32 nIndentPrefix(-1);
+            if (m_bAllowLineBreak)
+            {
+                sal_Int32 nFirstLineBreakOccurrence = getFirstLineBreak( aChars );
+
+                nLength = calcXMLByteLength( aChars, ! m_bIsCDATA , false );
+                nIndentPrefix = getIndentPrefixLength(
+                    nFirstLineBreakOccurrence >= 0 ? nFirstLineBreakOccurrence : nLength );
+            }
+            else
+                nIndentPrefix = getIndentPrefixLength(nLength);
+
+            // insert indentation
+            if( nIndentPrefix >= 0 )
+            {
+                if( isFirstCharWhitespace( aChars.getStr() ) )
+                    m_pSaxWriterHelper->insertIndentation( nIndentPrefix - 1 );
+                else
+                    m_pSaxWriterHelper->insertIndentation( nIndentPrefix );
+            }
+            bThrowException = !m_pSaxWriterHelper->writeString(aChars, true , false);
+        }
+    }
+    if (bThrowException)
+    {
+        SAXInvalidCharacterException except;
+        except.Message = "Invalid character during XML-Export";
+        throw except;
+    }
+}
+
+
+void SAXWriter::ignorableWhitespace(const OUString&)
+{
+    if( ! m_bDocStarted )
+    {
+        throw SAXException ();
+    }
+
+    m_bForceLineBreak = true;
+}
+
+void SAXWriter::processingInstruction(const OUString& aTarget, const OUString& aData)
+{
+    if( ! m_bDocStarted || m_bIsCDATA )
+    {
+        throw SAXException();
+    }
+
+    sal_Int32 nLength(0);
+    if (m_bAllowLineBreak)
+    {
+        nLength = 2;  // "<?"
+        nLength += calcXMLByteLength( aTarget, false, false );
+
+        nLength += 1;  // " "
+
+        nLength += calcXMLByteLength( aData, false, false );
+
+        nLength += 2; // "?>"
+    }
+
+    sal_Int32 nPrefix = getIndentPrefixLength( nLength );
+
+    if( nPrefix >= 0 )
+        m_pSaxWriterHelper->insertIndentation( nPrefix );
+
+    if (!m_pSaxWriterHelper->processingInstruction(aTarget, aData))
+    {
+        SAXException except;
+        except.Message = "Invalid character during XML-Export";
+        throw except;
+    }
+}
+
+
+void SAXWriter::setDocumentLocator(const Reference< XLocator >&)
+{
+
+}
+
+void SAXWriter::startCDATA()
+{
+    if( ! m_bDocStarted || m_bIsCDATA)
+    {
+        throw SAXException ();
+    }
+
+    sal_Int32 nPrefix = getIndentPrefixLength( 9 );
+    if( nPrefix >= 0 )
+        m_pSaxWriterHelper->insertIndentation( nPrefix );
+
+    m_pSaxWriterHelper->startCDATA();
+
+    m_bIsCDATA = true;
+}
+
+void SAXWriter::endCDATA()
+{
+    if( ! m_bDocStarted || ! m_bIsCDATA)
+    {
+        SAXException except;
+        except.Message = "endCDATA was called without startCDATA";
+        throw except;
+    }
+
+    sal_Int32 nPrefix = getIndentPrefixLength( 3 );
+    if( nPrefix >= 0 )
+        m_pSaxWriterHelper->insertIndentation( nPrefix );
+
+    m_pSaxWriterHelper->endCDATA();
+
+    m_bIsCDATA = false;
+}
+
+
+void SAXWriter::comment(const OUString& sComment)
+{
+    if( ! m_bDocStarted || m_bIsCDATA )
+    {
+        throw SAXException();
+    }
+
+    sal_Int32 nLength(0);
+    if (m_bAllowLineBreak)
+    {
+        nLength = 4; // "<!--"
+        nLength += calcXMLByteLength( sComment, false, false);
+
+        nLength += 3;
+    }
+
+    sal_Int32 nPrefix = getIndentPrefixLength( nLength );
+    if( nPrefix >= 0 )
+        m_pSaxWriterHelper->insertIndentation( nPrefix );
+
+    if (!m_pSaxWriterHelper->comment(sComment))
+    {
+        SAXException except;
+        except.Message = "Invalid character during XML-Export";
+        throw except;
+    }
+}
+
+
+void SAXWriter::allowLineBreak( )
+{
+    if( ! m_bDocStarted || m_bAllowLineBreak ) {
+        throw SAXException();
+    }
+
+    m_bAllowLineBreak = true;
+}
+
+void SAXWriter::unknown(const OUString& sString)
+{
+
+    if( ! m_bDocStarted )
+    {
+        throw SAXException ();
+    }
+    if( m_bIsCDATA )
+    {
+        throw SAXException();
+    }
+
+    if( sString.startsWith( "<?xml" ) )
+        return;
+
+    sal_Int32 nLength(0);
+    if (m_bAllowLineBreak)
+        nLength = calcXMLByteLength( sString, false, false );
+
+    sal_Int32 nPrefix = getIndentPrefixLength( nLength );
+    if( nPrefix >= 0 )
+        m_pSaxWriterHelper->insertIndentation( nPrefix );
+
+    if (!m_pSaxWriterHelper->writeString( sString, false, false))
+    {
+        SAXException except;
+        except.Message = "Invalid character during XML-Export";
+        throw except;
+    }
+}
+
+} // namespace
+
+extern "C" SAL_DLLPUBLIC_EXPORT css::uno::XInterface *
+com_sun_star_extensions_xml_sax_Writer_get_implementation(
+    css::uno::XComponentContext *,
+    css::uno::Sequence<css::uno::Any> const &)
+{
+    return cppu::acquire(new SAXWriter);
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sax/source/expatwrap/xml2utf.cxx b/sax/source/expatwrap/xml2utf.cxx
new file mode 100644
index 000000000..420f90b6c
--- /dev/null
+++ b/sax/source/expatwrap/xml2utf.cxx
@@ -0,0 +1,519 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+#include <string.h>
+
+#include <algorithm>
+
+#include <sal/types.h>
+
+#include <rtl/textenc.h>
+#include <rtl/tencinfo.h>
+#include <com/sun/star/io/NotConnectedException.hpp>
+#include <com/sun/star/io/XInputStream.hpp>
+
+using namespace ::com::sun::star::uno;
+using namespace ::com::sun::star::io;
+
+
+#include <xml2utf.hxx>
+#include <memory>
+
+namespace sax_expatwrap {
+
+sal_Int32 XMLFile2UTFConverter::readAndConvert( Sequence<sal_Int8> &seq , sal_Int32 nMaxToRead )
+{
+    if( ! m_in.is() ) {
+        throw NotConnectedException();
+    }
+    if( ! m_bStarted ) {
+        // it should be possible to find the encoding attribute
+        // within the first 512 bytes == 128 chars in UCS-4
+        nMaxToRead = ::std::max( sal_Int32(512) , nMaxToRead );
+    }
+
+    sal_Int32 nRead;
+    Sequence< sal_Int8 > seqStart;
+    while( true )
+    {
+        nRead = m_in->readSomeBytes( seq , nMaxToRead );
+
+        if( nRead + seqStart.getLength())
+        {
+            // if nRead is 0, the file is already eof.
+            if( ! m_bStarted && nRead )
+            {
+                // ensure that enough data is available to parse encoding
+                if( seqStart.hasElements() )
+                {
+                  // prefix with what we had so far.
+                  sal_Int32 nLength = seq.getLength();
+                  seq.realloc( seqStart.getLength() + nLength );
+
+                  memmove (seq.getArray() + seqStart.getLength(),
+                       seq.getConstArray(),
+                       nLength);
+                  memcpy  (seq.getArray(),
+                       seqStart.getConstArray(),
+                       seqStart.getLength());
+                }
+
+                // autodetection with the first bytes
+                if( ! isEncodingRecognizable( seq ) )
+                {
+                  // remember what we have so far.
+                  seqStart = seq;
+
+                  // read more !
+                  continue;
+                }
+                if( scanForEncoding( seq ) || !m_sEncoding.isEmpty() ) {
+                    // initialize decoding
+                    initializeDecoding();
+                }
+                seqStart = Sequence < sal_Int8 > ();
+            }
+
+            // do the encoding
+            if( m_pText2Unicode && m_pUnicode2Text &&
+                m_pText2Unicode->canContinue() ) {
+
+                Sequence<sal_Unicode> seqUnicode = m_pText2Unicode->convert( seq );
+                seq = m_pUnicode2Text->convert( seqUnicode.getConstArray(), seqUnicode.getLength() );
+            }
+
+            if( ! m_bStarted )
+            {
+                // it must now be ensured, that no encoding attribute exist anymore
+                // ( otherwise the expat-Parser will crash )
+                // This must be done after decoding !
+                // ( e.g. Files decoded in ucs-4 cannot be read properly )
+                m_bStarted = true;
+                removeEncoding( seq );
+            }
+            nRead = seq.getLength();
+        }
+
+        break;
+    }
+    return nRead;
+}
+
+void XMLFile2UTFConverter::removeEncoding( Sequence<sal_Int8> &seq )
+{
+    const sal_Int8 *pSource = seq.getArray();
+    if (!(seq.getLength() >= 5 && !strncmp(reinterpret_cast<const char *>(pSource), "<?xml", 5)))
+        return;
+
+    // scan for encoding
+    OString str( reinterpret_cast<char const *>(pSource), seq.getLength() );
+
+    // cut sequence to first line break
+    // find first line break;
+    int nMax = str.indexOf( 10 );
+    if( nMax >= 0 )
+    {
+        str = str.copy( 0 , nMax );
+    }
+
+    int nFound = str.indexOf( " encoding" );
+    if( nFound < 0 )        return;
+
+    int nStop;
+    int nStart = str.indexOf( "\"" , nFound );
+    if( nStart < 0 || str.indexOf( "'" , nFound ) < nStart )
+    {
+        nStart = str.indexOf( "'" , nFound );
+        nStop  = str.indexOf( "'" , nStart +1 );
+    }
+    else
+    {
+        nStop  = str.indexOf( "\"" , nStart +1);
+    }
+
+    if( nStart >= 0 && nStop >= 0 && nStart+1 < nStop )
+    {
+        // remove encoding tag from file
+        memmove(        &( seq.getArray()[nFound] ) ,
+                        &( seq.getArray()[nStop+1]) ,
+                        seq.getLength() - nStop -1);
+        seq.realloc( seq.getLength() - ( nStop+1 - nFound ) );
+    }
+}
+
+// Checks, if enough data has been accumulated to recognize the encoding
+bool XMLFile2UTFConverter::isEncodingRecognizable( const Sequence< sal_Int8 > &seq)
+{
+    const sal_Int8 *pSource = seq.getConstArray();
+    bool bCheckIfFirstClosingBracketExsists = false;
+
+    if( seq.getLength() < 8 ) {
+        // no recognition possible, when less than 8 bytes are available
+        return false;
+    }
+
+    if( ! strncmp( reinterpret_cast<const char *>(pSource), "<?xml", 5 ) ) {
+        // scan if the <?xml tag finishes within this buffer
+        bCheckIfFirstClosingBracketExsists = true;
+    }
+    else if( ('<' == pSource[0] || '<' == pSource[2] ) &&
+             ('?' == pSource[4] || '?' == pSource[6] ) )
+    {
+        // check for utf-16
+        bCheckIfFirstClosingBracketExsists = true;
+    }
+    else if( ( '<' == pSource[1] || '<' == pSource[3] ) &&
+             ( '?' == pSource[5] || '?' == pSource[7] ) )
+    {
+        // check for
+        bCheckIfFirstClosingBracketExsists = true;
+    }
+
+    if( bCheckIfFirstClosingBracketExsists )
+    {
+        // whole <?xml tag is valid
+        return std::find(seq.begin(), seq.end(), '>') != seq.end();
+    }
+
+    // No <? tag in front, no need for a bigger buffer
+    return true;
+}
+
+bool XMLFile2UTFConverter::scanForEncoding( Sequence< sal_Int8 > &seq )
+{
+    const sal_uInt8 *pSource = reinterpret_cast<const sal_uInt8*>( seq.getConstArray() );
+    bool bReturn = true;
+
+    if( seq.getLength() < 4 ) {
+        // no recognition possible, when less than 4 bytes are available
+        return false;
+    }
+
+    // first level : detect possible file formats
+    if (seq.getLength() >= 5 && !strncmp(reinterpret_cast<const char *>(pSource), "<?xml", 5)) {
+        // scan for encoding
+        OString str( reinterpret_cast<const char *>(pSource), seq.getLength() );
+
+        // cut sequence to first line break
+        //find first line break;
+        int nMax = str.indexOf( 10 );
+        if( nMax >= 0 )
+        {
+            str = str.copy( 0 , nMax );
+        }
+
+        int nFound = str.indexOf( " encoding" );
+        if( nFound >= 0 ) {
+            int nStop;
+            int nStart = str.indexOf( "\"" , nFound );
+            if( nStart < 0 || str.indexOf( "'" , nFound ) < nStart )
+            {
+                nStart = str.indexOf( "'" , nFound );
+                nStop  = str.indexOf( "'" , nStart +1 );
+            }
+            else
+            {
+                nStop  = str.indexOf( "\"" , nStart +1);
+            }
+            if( nStart >= 0 && nStop >= 0 && nStart+1 < nStop )
+            {
+                // encoding found finally
+                m_sEncoding = str.copy( nStart+1 , nStop - nStart - 1 );
+            }
+        }
+    }
+    else if( 0xFE == pSource[0] &&
+             0xFF == pSource[1] ) {
+        // UTF-16 big endian
+        // conversion is done so that encoding information can be easily extracted
+        m_sEncoding = "utf-16";
+    }
+    else if( 0xFF == pSource[0] &&
+             0xFE == pSource[1] ) {
+        // UTF-16 little endian
+        // conversion is done so that encoding information can be easily extracted
+        m_sEncoding = "utf-16";
+    }
+    else if( 0x00 == pSource[0] && 0x3c == pSource[1]  && 0x00 == pSource[2] && 0x3f == pSource[3] ) {
+        // UTF-16 big endian without byte order mark (this is (strictly speaking) an error.)
+        // The byte order mark is simply added
+
+        // simply add the byte order mark !
+        seq.realloc( seq.getLength() + 2 );
+        memmove( &( seq.getArray()[2] ) , seq.getArray() , seq.getLength() - 2 );
+        reinterpret_cast<sal_uInt8*>(seq.getArray())[0] = 0xFE;
+        reinterpret_cast<sal_uInt8*>(seq.getArray())[1] = 0xFF;
+
+        m_sEncoding = "utf-16";
+    }
+    else if( 0x3c == pSource[0] && 0x00 == pSource[1]  && 0x3f == pSource[2] && 0x00 == pSource[3] ) {
+        // UTF-16 little endian without byte order mark (this is (strictly speaking) an error.)
+        // The byte order mark is simply added
+
+        seq.realloc( seq.getLength() + 2 );
+        memmove( &( seq.getArray()[2] ) , seq.getArray() , seq.getLength() - 2 );
+        reinterpret_cast<sal_uInt8*>(seq.getArray())[0] = 0xFF;
+        reinterpret_cast<sal_uInt8*>(seq.getArray())[1] = 0xFE;
+
+        m_sEncoding = "utf-16";
+    }
+    else if( 0xEF == pSource[0] &&
+             0xBB == pSource[1] &&
+             0xBF == pSource[2] )
+    {
+        // UTF-8 BOM (byte order mark); signifies utf-8, and not byte order
+        // The BOM is removed.
+        memmove( seq.getArray(), &( seq.getArray()[3] ), seq.getLength()-3 );
+        seq.realloc( seq.getLength() - 3 );
+        m_sEncoding = "utf-8";
+    }
+    else if( 0x00 == pSource[0] && 0x00 == pSource[1]  && 0x00 == pSource[2] && 0x3c == pSource[3] ) {
+        // UCS-4 big endian
+        m_sEncoding = "ucs-4";
+    }
+    else if( 0x3c == pSource[0] && 0x00 == pSource[1]  && 0x00 == pSource[2] && 0x00 == pSource[3] ) {
+        // UCS-4 little endian
+        m_sEncoding = "ucs-4";
+    }
+/* TODO: no need to test for the moment since we return sal_False like default case anyway
+    else if( 0x4c == pSource[0] && 0x6f == pSource[1]  &&
+             0xa7 == static_cast<unsigned char> (pSource[2]) &&
+             0x94 == static_cast<unsigned char> (pSource[3]) ) {
+        // EBCDIC
+        bReturn = sal_False;   // must be extended
+    }
+*/
+    else {
+        // other
+        // UTF8 is directly recognized by the parser.
+        bReturn = false;
+    }
+
+    return bReturn;
+}
+
+void XMLFile2UTFConverter::initializeDecoding()
+{
+
+    if( !m_sEncoding.isEmpty() )
+    {
+        rtl_TextEncoding encoding = rtl_getTextEncodingFromMimeCharset( m_sEncoding.getStr() );
+        if( encoding != RTL_TEXTENCODING_UTF8 )
+        {
+            m_pText2Unicode = std::make_unique<Text2UnicodeConverter>( m_sEncoding );
+            m_pUnicode2Text = std::make_unique<Unicode2TextConverter>( RTL_TEXTENCODING_UTF8 );
+        }
+    }
+}
+
+
+// Text2UnicodeConverter
+
+
+Text2UnicodeConverter::Text2UnicodeConverter( const OString &sEncoding )
+    : m_convText2Unicode(nullptr)
+    , m_contextText2Unicode(nullptr)
+{
+    rtl_TextEncoding encoding = rtl_getTextEncodingFromMimeCharset( sEncoding.getStr() );
+    if( RTL_TEXTENCODING_DONTKNOW == encoding )
+    {
+        m_bCanContinue = false;
+        m_bInitialized = false;
+    }
+    else
+    {
+        init( encoding );
+    }
+}
+
+Text2UnicodeConverter::~Text2UnicodeConverter()
+{
+    if( m_bInitialized )
+    {
+        rtl_destroyTextToUnicodeContext( m_convText2Unicode , m_contextText2Unicode );
+        rtl_destroyUnicodeToTextConverter( m_convText2Unicode );
+    }
+}
+
+void Text2UnicodeConverter::init( rtl_TextEncoding encoding )
+{
+    m_bCanContinue = true;
+    m_bInitialized = true;
+
+    m_convText2Unicode  = rtl_createTextToUnicodeConverter(encoding);
+    m_contextText2Unicode = rtl_createTextToUnicodeContext( m_convText2Unicode );
+}
+
+
+Sequence<sal_Unicode> Text2UnicodeConverter::convert( const Sequence<sal_Int8> &seqText )
+{
+    sal_uInt32 uiInfo;
+    sal_Size nSrcCvtBytes   = 0;
+    sal_Size nTargetCount   = 0;
+    sal_Size nSourceCount   = 0;
+
+    // the whole source size
+    sal_Int32   nSourceSize = seqText.getLength() + m_seqSource.getLength();
+    Sequence<sal_Unicode>   seqUnicode ( nSourceSize );
+
+    const sal_Int8 *pbSource = seqText.getConstArray();
+    std::unique_ptr<sal_Int8[]> pbTempMem;
+
+    if( m_seqSource.hasElements() ) {
+        // put old rest and new byte sequence into one array
+        pbTempMem.reset(new sal_Int8[ nSourceSize ]);
+        memcpy( pbTempMem.get() , m_seqSource.getConstArray() , m_seqSource.getLength() );
+        memcpy( &(pbTempMem[ m_seqSource.getLength() ]) , seqText.getConstArray() , seqText.getLength() );
+        pbSource = pbTempMem.get();
+
+        // set to zero again
+        m_seqSource = Sequence< sal_Int8 >();
+    }
+
+    while( true ) {
+
+        /* All invalid characters are transformed to the unicode undefined char */
+        nTargetCount +=     rtl_convertTextToUnicode(
+                                    m_convText2Unicode,
+                                    m_contextText2Unicode,
+                                    reinterpret_cast<const char *>(&( pbSource[nSourceCount] )),
+                                    nSourceSize - nSourceCount ,
+                                    &( seqUnicode.getArray()[ nTargetCount ] ),
+                                    seqUnicode.getLength() - nTargetCount,
+                                    RTL_TEXTTOUNICODE_FLAGS_UNDEFINED_DEFAULT   |
+                                    RTL_TEXTTOUNICODE_FLAGS_MBUNDEFINED_DEFAULT |
+                                    RTL_TEXTTOUNICODE_FLAGS_INVALID_DEFAULT,
+                                    &uiInfo,
+                                    &nSrcCvtBytes );
+        nSourceCount += nSrcCvtBytes;
+
+        if( uiInfo & RTL_TEXTTOUNICODE_INFO_DESTBUFFERTOOSMALL ) {
+            // save necessary bytes for next conversion
+            seqUnicode.realloc( seqUnicode.getLength() * 2 );
+            continue;
+        }
+        break;
+    }
+    if( uiInfo & RTL_TEXTTOUNICODE_INFO_SRCBUFFERTOOSMALL ) {
+        m_seqSource.realloc( nSourceSize - nSourceCount );
+        memcpy( m_seqSource.getArray() , &(pbSource[nSourceCount]) , nSourceSize-nSourceCount );
+    }
+
+    // set to correct unicode size
+    seqUnicode.realloc( nTargetCount );
+
+    return seqUnicode;
+}
+
+
+// Unicode2TextConverter
+
+
+Unicode2TextConverter::Unicode2TextConverter( rtl_TextEncoding encoding )
+{
+    m_convUnicode2Text  = rtl_createUnicodeToTextConverter( encoding );
+    m_contextUnicode2Text = rtl_createUnicodeToTextContext( m_convUnicode2Text );
+}
+
+
+Unicode2TextConverter::~Unicode2TextConverter()
+{
+    rtl_destroyUnicodeToTextContext( m_convUnicode2Text , m_contextUnicode2Text );
+    rtl_destroyUnicodeToTextConverter( m_convUnicode2Text );
+}
+
+
+Sequence<sal_Int8> Unicode2TextConverter::convert(const sal_Unicode *puSource , sal_Int32 nSourceSize)
+{
+    std::unique_ptr<sal_Unicode[]> puTempMem;
+
+    if( m_seqSource.hasElements() ) {
+        // For surrogates !
+        // put old rest and new byte sequence into one array
+        // In general when surrogates are used, they should be rarely
+        // cut off between two convert()-calls. So this code is used
+        // rarely and the extra copy is acceptable.
+        puTempMem.reset(new sal_Unicode[ nSourceSize + m_seqSource.getLength()]);
+        memcpy( puTempMem.get() ,
+                m_seqSource.getConstArray() ,
+                m_seqSource.getLength() * sizeof( sal_Unicode ) );
+        memcpy(
+            &(puTempMem[ m_seqSource.getLength() ]) ,
+            puSource ,
+            nSourceSize*sizeof( sal_Unicode ) );
+        puSource = puTempMem.get();
+        nSourceSize += m_seqSource.getLength();
+
+        m_seqSource = Sequence< sal_Unicode > ();
+    }
+
+
+    sal_Size nTargetCount = 0;
+    sal_Size nSourceCount = 0;
+
+    sal_uInt32 uiInfo;
+    sal_Size nSrcCvtChars;
+
+    // take nSourceSize * 3 as preference
+    // this is an upper boundary for converting to utf8,
+    // which most often used as the target.
+    sal_Int32 nSeqSize =  nSourceSize * 3;
+
+    Sequence<sal_Int8>  seqText( nSeqSize );
+    char *pTarget = reinterpret_cast<char *>(seqText.getArray());
+    while( true ) {
+
+        nTargetCount += rtl_convertUnicodeToText(
+                                    m_convUnicode2Text,
+                                    m_contextUnicode2Text,
+                                    &( puSource[nSourceCount] ),
+                                    nSourceSize - nSourceCount ,
+                                    &( pTarget[nTargetCount] ),
+                                    nSeqSize - nTargetCount,
+                                    RTL_UNICODETOTEXT_FLAGS_UNDEFINED_DEFAULT |
+                                    RTL_UNICODETOTEXT_FLAGS_INVALID_DEFAULT ,
+                                    &uiInfo,
+                                    &nSrcCvtChars);
+        nSourceCount += nSrcCvtChars;
+
+        if( uiInfo & RTL_UNICODETOTEXT_INFO_DESTBUFFERTOSMALL ) {
+            nSeqSize = nSeqSize *2;
+            seqText.realloc( nSeqSize );  // double array size
+            pTarget = reinterpret_cast<char *>(seqText.getArray());
+            continue;
+        }
+        break;
+    }
+
+    // for surrogates
+    if( uiInfo & RTL_UNICODETOTEXT_INFO_SRCBUFFERTOSMALL ) {
+        m_seqSource.realloc( nSourceSize - nSourceCount );
+        memcpy( m_seqSource.getArray() ,
+                &(puSource[nSourceCount]),
+                (nSourceSize - nSourceCount) * sizeof( sal_Unicode ) );
+    }
+
+    // reduce the size of the buffer (fast, no copy necessary)
+    seqText.realloc( nTargetCount );
+
+    return seqText;
+}
+
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sax/source/fastparser/fastparser.cxx b/sax/source/fastparser/fastparser.cxx
new file mode 100644
index 000000000..a0488efa4
--- /dev/null
+++ b/sax/source/fastparser/fastparser.cxx
@@ -0,0 +1,1436 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <sax/fastparser.hxx>
+#include <sax/fastattribs.hxx>
+#include <xml2utf.hxx>
+
+#include <com/sun/star/io/XSeekable.hpp>
+#include <com/sun/star/lang/DisposedException.hpp>
+#include <com/sun/star/lang/IllegalArgumentException.hpp>
+#include <com/sun/star/uno/XComponentContext.hpp>
+#include <com/sun/star/xml/sax/FastToken.hpp>
+#include <com/sun/star/xml/sax/SAXParseException.hpp>
+#include <com/sun/star/xml/sax/XFastContextHandler.hpp>
+#include <com/sun/star/xml/sax/XFastDocumentHandler.hpp>
+#include <com/sun/star/xml/sax/XFastTokenHandler.hpp>
+#include <cppuhelper/implbase.hxx>
+#include <cppuhelper/supportsservice.hxx>
+#include <cppuhelper/exc_hlp.hxx>
+#include <osl/conditn.hxx>
+#include <rtl/ref.hxx>
+#include <rtl/ustrbuf.hxx>
+#include <sal/log.hxx>
+#include <salhelper/thread.hxx>
+#include <tools/diagnose_ex.h>
+
+#include <queue>
+#include <memory>
+#include <stack>
+#include <unordered_map>
+#include <vector>
+#include <cassert>
+#include <cstring>
+#include <libxml/parser.h>
+
+// Inverse of libxml's BAD_CAST.
+#define XML_CAST( str ) reinterpret_cast< const char* >( str )
+
+using namespace std;
+using namespace ::osl;
+using namespace ::cppu;
+using namespace ::com::sun::star::uno;
+using namespace ::com::sun::star::lang;
+using namespace ::com::sun::star::xml::sax;
+using namespace ::com::sun::star::io;
+using namespace com::sun::star;
+using namespace sax_fastparser;
+
+namespace {
+
+struct Event;
+class FastLocatorImpl;
+struct NamespaceDefine;
+struct Entity;
+
+typedef std::unordered_map< OUString, sal_Int32 > NamespaceMap;
+
+struct EventList
+{
+    std::vector<Event> maEvents;
+    bool mbIsAttributesEmpty;
+};
+
+enum class CallbackType { START_ELEMENT, END_ELEMENT, CHARACTERS, PROCESSING_INSTRUCTION, DONE, EXCEPTION };
+
+struct Event
+{
+    CallbackType maType;
+    sal_Int32 mnElementToken;
+    OUString msNamespace;
+    OUString msElementName;
+    rtl::Reference< FastAttributeList > mxAttributes;
+    rtl::Reference< FastAttributeList > mxDeclAttributes;
+    OUString msChars;
+};
+
+struct NameWithToken
+{
+    OUString msName;
+    sal_Int32 mnToken;
+
+    NameWithToken(const OUString& sName, sal_Int32 nToken) :
+        msName(sName), mnToken(nToken) {}
+};
+
+struct SaxContext
+{
+    Reference< XFastContextHandler > mxContext;
+    sal_Int32 mnElementToken;
+    OUString  maNamespace;
+    OUString  maElementName;
+
+    SaxContext( sal_Int32 nElementToken, const OUString& aNamespace, const OUString& aElementName ):
+            mnElementToken(nElementToken)
+    {
+        if (nElementToken == FastToken::DONTKNOW)
+        {
+            maNamespace = aNamespace;
+            maElementName = aElementName;
+        }
+    }
+};
+
+
+struct ParserData
+{
+    css::uno::Reference< css::xml::sax::XFastDocumentHandler > mxDocumentHandler;
+    rtl::Reference<FastTokenHandlerBase>                       mxTokenHandler;
+    css::uno::Reference< css::xml::sax::XErrorHandler >        mxErrorHandler;
+    css::uno::Reference< css::xml::sax::XFastNamespaceHandler >mxNamespaceHandler;
+
+    ParserData();
+};
+
+struct NamespaceDefine
+{
+    OString     maPrefix;
+    sal_Int32   mnToken;
+    OUString    maNamespaceURL;
+
+    NamespaceDefine( const OString& rPrefix, sal_Int32 nToken, const OUString& rNamespaceURL ) : maPrefix( rPrefix ), mnToken( nToken ), maNamespaceURL( rNamespaceURL ) {}
+    NamespaceDefine() : mnToken(-1) {}
+};
+
+// Entity binds all information needed for a single file | single call of parseStream
+struct Entity : public ParserData
+{
+    // Amount of work producer sends to consumer in one iteration:
+    static const size_t mnEventListSize = 1000;
+
+    // unique for each Entity instance:
+
+    // Number of valid events in mxProducedEvents:
+    size_t mnProducedEventsSize;
+    std::unique_ptr<EventList> mxProducedEvents;
+    std::queue<std::unique_ptr<EventList>> maPendingEvents;
+    std::queue<std::unique_ptr<EventList>> maUsedEvents;
+    osl::Mutex maEventProtector;
+
+    static const size_t mnEventLowWater = 4;
+    static const size_t mnEventHighWater = 8;
+    osl::Condition maConsumeResume;
+    osl::Condition maProduceResume;
+    // Event we use to store data if threading is disabled:
+    Event maSharedEvent;
+
+    // copied in copy constructor:
+
+    // Allow to disable threading for small documents:
+    bool                                    mbEnableThreads;
+    css::xml::sax::InputSource              maStructSource;
+    xmlParserCtxtPtr                        mpParser;
+    ::sax_expatwrap::XMLFile2UTFConverter   maConverter;
+
+    // Exceptions cannot be thrown through the C-XmlParser (possible
+    // resource leaks), therefore any exception thrown by a UNO callback
+    // must be saved somewhere until the C-XmlParser is stopped.
+    css::uno::Any                           maSavedException;
+    osl::Mutex maSavedExceptionMutex;
+    void saveException( const Any & e );
+    // Thread-safe check if maSavedException has value
+    bool hasException();
+    void throwException( const ::rtl::Reference< FastLocatorImpl > &xDocumentLocator,
+                         bool mbDuringParse );
+
+    std::stack< NameWithToken, std::vector<NameWithToken> > maNamespaceStack;
+    /* Context for main thread consuming events.
+     * startElement() stores the data, which characters() and endElement() uses
+     */
+    std::stack< SaxContext, std::vector<SaxContext> >  maContextStack;
+    // Determines which elements of maNamespaceDefines are valid in current context
+    std::stack< sal_uInt32, std::vector<sal_uInt32> >  maNamespaceCount;
+    std::vector< NamespaceDefine >                     maNamespaceDefines;
+
+    explicit Entity( const ParserData& rData );
+    Entity( const Entity& rEntity ) = delete;
+    Entity& operator=( const Entity& rEntity ) = delete;
+    void startElement( Event const *pEvent );
+    void characters( const OUString& sChars );
+    void endElement();
+    void processingInstruction( const OUString& rTarget, const OUString& rData );
+    EventList& getEventList();
+    Event& getEvent( CallbackType aType );
+};
+
+} // namespace
+
+namespace sax_fastparser {
+
+class FastSaxParserImpl
+{
+public:
+    explicit FastSaxParserImpl();
+    ~FastSaxParserImpl();
+
+    // XFastParser
+    /// @throws css::xml::sax::SAXException
+    /// @throws css::io::IOException
+    /// @throws css::uno::RuntimeException
+    void parseStream( const css::xml::sax::InputSource& aInputSource );
+    /// @throws css::uno::RuntimeException
+    void setFastDocumentHandler( const css::uno::Reference< css::xml::sax::XFastDocumentHandler >& Handler );
+    /// @throws css::uno::RuntimeException
+    void setTokenHandler( const css::uno::Reference< css::xml::sax::XFastTokenHandler >& Handler );
+    /// @throws css::lang::IllegalArgumentException
+    /// @throws css::uno::RuntimeException
+    void registerNamespace( const OUString& NamespaceURL, sal_Int32 NamespaceToken );
+    /// @throws css::lang::IllegalArgumentException
+    /// @throws css::uno::RuntimeException
+    OUString const & getNamespaceURL( const OUString& rPrefix );
+    /// @throws css::uno::RuntimeException
+    void setErrorHandler( const css::uno::Reference< css::xml::sax::XErrorHandler >& Handler );
+    /// @throws css::uno::RuntimeException
+    void setNamespaceHandler( const css::uno::Reference< css::xml::sax::XFastNamespaceHandler >& Handler);
+
+    // called by the C callbacks of the expat parser
+    void callbackStartElement( const xmlChar *localName , const xmlChar* prefix, const xmlChar* URI,
+        int numNamespaces, const xmlChar** namespaces, int numAttributes, const xmlChar **attributes );
+    void callbackEndElement();
+    void callbackCharacters( const xmlChar* s, int nLen );
+    void callbackProcessingInstruction( const xmlChar *target, const xmlChar *data );
+
+    void pushEntity(const ParserData&, xml::sax::InputSource const&);
+    void popEntity();
+    Entity& getEntity()             { return *mpTop; }
+    void parse();
+    void produce( bool bForceFlush = false );
+    bool m_bIgnoreMissingNSDecl;
+    bool m_bDisableThreadedParser;
+
+private:
+    bool consume(EventList&);
+    void deleteUsedEvents();
+    void sendPendingCharacters();
+    void addUnknownElementWithPrefix(const xmlChar **attributes, int i, rtl::Reference< FastAttributeList > const & xAttributes);
+
+    sal_Int32 GetToken( const xmlChar* pName, sal_Int32 nameLen );
+    /// @throws css::xml::sax::SAXException
+    sal_Int32 GetTokenWithPrefix( const xmlChar* pPrefix, int prefixLen, const xmlChar* pName, int nameLen );
+    /// @throws css::xml::sax::SAXException
+    OUString const & GetNamespaceURL( const OString& rPrefix );
+    sal_Int32 GetNamespaceToken( const OUString& rNamespaceURL );
+    sal_Int32 GetTokenWithContextNamespace( sal_Int32 nNamespaceToken, const xmlChar* pName, int nNameLen );
+    void DefineNamespace( const OString& rPrefix, const OUString& namespaceURL );
+
+private:
+    osl::Mutex maMutex; ///< Protecting whole parseStream() execution
+    ::rtl::Reference< FastLocatorImpl >     mxDocumentLocator;
+    NamespaceMap                            maNamespaceMap;
+
+    ParserData maData;                      /// Cached parser configuration for next call of parseStream().
+
+    Entity *mpTop;                          /// std::stack::top() is amazingly slow => cache this.
+    std::stack< Entity > maEntities;        /// Entity stack for each call of parseStream().
+    std::vector<char> pendingCharacters;    /// Data from characters() callback that needs to be sent.
+};
+
+} // namespace sax_fastparser
+
+namespace {
+
+class ParserThread: public salhelper::Thread
+{
+    FastSaxParserImpl *mpParser;
+public:
+    explicit ParserThread(FastSaxParserImpl *pParser): Thread("Parser"), mpParser(pParser) {}
+private:
+    virtual void execute() override
+    {
+        try
+        {
+            mpParser->parse();
+        }
+        catch (...)
+        {
+            Entity &rEntity = mpParser->getEntity();
+            rEntity.getEvent( CallbackType::EXCEPTION );
+            mpParser->produce( true );
+        }
+    }
+};
+
+extern "C" {
+
+static void call_callbackStartElement(void *userData, const xmlChar *localName , const xmlChar* prefix, const xmlChar* URI,
+    int numNamespaces, const xmlChar** namespaces, int numAttributes, int /*defaultedAttributes*/, const xmlChar **attributes)
+{
+    FastSaxParserImpl* pFastParser = static_cast<FastSaxParserImpl*>( userData );
+    pFastParser->callbackStartElement( localName, prefix, URI, numNamespaces, namespaces, numAttributes, attributes );
+}
+
+static void call_callbackEndElement(void *userData, const xmlChar* /*localName*/, const xmlChar* /*prefix*/, const xmlChar* /*URI*/)
+{
+    FastSaxParserImpl* pFastParser = static_cast<FastSaxParserImpl*>( userData );
+    pFastParser->callbackEndElement();
+}
+
+static void call_callbackCharacters( void *userData , const xmlChar *s , int nLen )
+{
+    FastSaxParserImpl* pFastParser = static_cast<FastSaxParserImpl*>( userData );
+    pFastParser->callbackCharacters( s, nLen );
+}
+
+static void call_callbackProcessingInstruction( void *userData, const xmlChar *target, const xmlChar *data )
+{
+    FastSaxParserImpl* pFastParser = static_cast<FastSaxParserImpl*>( userData );
+    pFastParser->callbackProcessingInstruction( target, data );
+}
+
+}
+
+class FastLocatorImpl : public WeakImplHelper< XLocator >
+{
+public:
+    explicit FastLocatorImpl(FastSaxParserImpl *p) : mpParser(p) {}
+
+    void dispose() { mpParser = nullptr; }
+    /// @throws RuntimeException
+    void checkDispose() const { if( !mpParser ) throw DisposedException(); }
+
+    //XLocator
+    virtual sal_Int32 SAL_CALL getColumnNumber() override;
+    virtual sal_Int32 SAL_CALL getLineNumber() override;
+    virtual OUString SAL_CALL getPublicId() override;
+    virtual OUString SAL_CALL getSystemId() override;
+
+private:
+    FastSaxParserImpl *mpParser;
+};
+
+sal_Int32 SAL_CALL FastLocatorImpl::getColumnNumber()
+{
+    checkDispose();
+    return xmlSAX2GetColumnNumber( mpParser->getEntity().mpParser );
+}
+
+sal_Int32 SAL_CALL FastLocatorImpl::getLineNumber()
+{
+    checkDispose();
+    return xmlSAX2GetLineNumber( mpParser->getEntity().mpParser );
+}
+
+OUString SAL_CALL FastLocatorImpl::getPublicId()
+{
+    checkDispose();
+    return mpParser->getEntity().maStructSource.sPublicId;
+}
+
+OUString SAL_CALL FastLocatorImpl::getSystemId()
+{
+    checkDispose();
+    return mpParser->getEntity().maStructSource.sSystemId;
+}
+
+ParserData::ParserData()
+{}
+
+Entity::Entity(const ParserData& rData)
+    : ParserData(rData)
+    , mnProducedEventsSize(0)
+    , mxProducedEvents()
+    , mbEnableThreads(false)
+    , mpParser(nullptr)
+{
+}
+
+void Entity::startElement( Event const *pEvent )
+{
+    const sal_Int32& nElementToken = pEvent->mnElementToken;
+    const OUString& aNamespace = pEvent->msNamespace;
+    const OUString& aElementName = pEvent->msElementName;
+
+    // Use un-wrapped pointers to avoid significant acquire/release overhead
+    XFastContextHandler *pParentContext = nullptr;
+    if( !maContextStack.empty() )
+    {
+        pParentContext = maContextStack.top().mxContext.get();
+        if( !pParentContext )
+        {
+            maContextStack.push( SaxContext(nElementToken, aNamespace, aElementName) );
+            return;
+        }
+    }
+
+    maContextStack.push( SaxContext( nElementToken, aNamespace, aElementName ) );
+
+    try
+    {
+        Reference< XFastAttributeList > xAttr( pEvent->mxAttributes.get() );
+        Reference< XFastContextHandler > xContext;
+
+        if ( mxNamespaceHandler.is() )
+        {
+            const Sequence< xml::Attribute > NSDeclAttribs = pEvent->mxDeclAttributes->getUnknownAttributes();
+            for (const auto& rNSDeclAttrib : NSDeclAttribs)
+            {
+                mxNamespaceHandler->registerNamespace( rNSDeclAttrib.Name, rNSDeclAttrib.Value );
+            }
+        }
+
+        if( nElementToken == FastToken::DONTKNOW )
+        {
+            if( pParentContext )
+                xContext = pParentContext->createUnknownChildContext( aNamespace, aElementName, xAttr );
+            else if( mxDocumentHandler.is() )
+                xContext = mxDocumentHandler->createUnknownChildContext( aNamespace, aElementName, xAttr );
+
+            if( xContext.is() )
+            {
+                xContext->startUnknownElement( aNamespace, aElementName, xAttr );
+            }
+        }
+        else
+        {
+            if( pParentContext )
+                xContext = pParentContext->createFastChildContext( nElementToken, xAttr );
+            else if( mxDocumentHandler.is() )
+                xContext = mxDocumentHandler->createFastChildContext( nElementToken, xAttr );
+
+            if( xContext.is() )
+                xContext->startFastElement( nElementToken, xAttr );
+        }
+        // swap the reference we own in to avoid referencing thrash.
+        maContextStack.top().mxContext = std::move( xContext );
+    }
+    catch (...)
+    {
+        saveException( ::cppu::getCaughtException() );
+    }
+}
+
+void Entity::characters( const OUString& sChars )
+{
+    if (maContextStack.empty())
+    {
+        // Malformed XML stream !?
+        return;
+    }
+
+    XFastContextHandler * pContext( maContextStack.top().mxContext.get() );
+    if( pContext ) try
+    {
+        pContext->characters( sChars );
+    }
+    catch (...)
+    {
+        saveException( ::cppu::getCaughtException() );
+    }
+}
+
+void Entity::endElement()
+{
+    if (maContextStack.empty())
+    {
+        // Malformed XML stream !?
+        return;
+    }
+
+    const SaxContext& aContext = maContextStack.top();
+    XFastContextHandler* pContext( aContext.mxContext.get() );
+    if( pContext )
+        try
+        {
+            sal_Int32 nElementToken = aContext.mnElementToken;
+            if( nElementToken != FastToken::DONTKNOW )
+                pContext->endFastElement( nElementToken );
+            else
+                pContext->endUnknownElement( aContext.maNamespace, aContext.maElementName );
+        }
+        catch (...)
+        {
+            saveException( ::cppu::getCaughtException() );
+        }
+    maContextStack.pop();
+}
+
+void Entity::processingInstruction( const OUString& rTarget, const OUString& rData )
+{
+    if( mxDocumentHandler.is() ) try
+    {
+        mxDocumentHandler->processingInstruction( rTarget, rData );
+    }
+    catch (...)
+    {
+        saveException( ::cppu::getCaughtException() );
+    }
+}
+
+EventList& Entity::getEventList()
+{
+    if (!mxProducedEvents)
+    {
+        osl::ClearableMutexGuard aGuard(maEventProtector);
+        if (!maUsedEvents.empty())
+        {
+            mxProducedEvents = std::move(maUsedEvents.front());
+            maUsedEvents.pop();
+            aGuard.clear(); // unlock
+            mnProducedEventsSize = 0;
+        }
+        if (!mxProducedEvents)
+        {
+            mxProducedEvents.reset(new EventList);
+            mxProducedEvents->maEvents.resize(mnEventListSize);
+            mxProducedEvents->mbIsAttributesEmpty = false;
+            mnProducedEventsSize = 0;
+        }
+    }
+    return *mxProducedEvents;
+}
+
+Event& Entity::getEvent( CallbackType aType )
+{
+    if (!mbEnableThreads)
+        return maSharedEvent;
+
+    EventList& rEventList = getEventList();
+    if (mnProducedEventsSize == rEventList.maEvents.size())
+    {
+        SAL_WARN_IF(!maSavedException.hasValue(), "sax",
+            "Event vector should only exceed " << mnEventListSize <<
+            " temporarily while an exception is pending");
+        rEventList.maEvents.resize(mnProducedEventsSize + 1);
+    }
+    Event& rEvent = rEventList.maEvents[mnProducedEventsSize++];
+    rEvent.maType = aType;
+    return rEvent;
+}
+
+OUString lclGetErrorMessage( xmlParserCtxtPtr ctxt, const OUString& sSystemId, sal_Int32 nLine )
+{
+    const char* pMessage;
+    xmlErrorPtr error = xmlCtxtGetLastError( ctxt );
+    if( error && error->message )
+        pMessage = error->message;
+    else
+        pMessage = "unknown error";
+    OUStringBuffer aBuffer( 128 );
+    aBuffer.append( "[" );
+    aBuffer.append( sSystemId );
+    aBuffer.append( " line " );
+    aBuffer.append( nLine );
+    aBuffer.append( "]: " );
+    aBuffer.appendAscii( pMessage );
+    return aBuffer.makeStringAndClear();
+}
+
+// throw an exception, but avoid callback if
+// during a threaded produce
+void Entity::throwException( const ::rtl::Reference< FastLocatorImpl > &xDocumentLocator,
+                             bool mbDuringParse )
+{
+    // Error during parsing !
+    Any savedException;
+    {
+        osl::MutexGuard g(maSavedExceptionMutex);
+        if (maSavedException.hasValue())
+        {
+            savedException.setValue(&maSavedException, cppu::UnoType<decltype(maSavedException)>::get());
+        }
+    }
+    SAXParseException aExcept(
+        lclGetErrorMessage( mpParser,
+                            xDocumentLocator->getSystemId(),
+                            xDocumentLocator->getLineNumber() ),
+        Reference< XInterface >(),
+        savedException,
+        xDocumentLocator->getPublicId(),
+        xDocumentLocator->getSystemId(),
+        xDocumentLocator->getLineNumber(),
+        xDocumentLocator->getColumnNumber()
+    );
+
+    // error handler is set, it may throw the exception
+    if( !mbDuringParse || !mbEnableThreads )
+    {
+        if (mxErrorHandler.is() )
+            mxErrorHandler->fatalError( Any( aExcept ) );
+    }
+
+    // error handler has not thrown, but parsing must stop => throw ourselves
+    throw aExcept;
+}
+
+// In the single threaded case we emit events via our C
+// callbacks, so any exception caught must be queued up until
+// we can safely re-throw it from our C++ parent of parse()
+
+// If multi-threaded, we need to push an EXCEPTION event, at
+// which point we transfer ownership of maSavedException to
+// the consuming thread.
+void Entity::saveException( const Any & e )
+{
+    // fdo#81214 - allow the parser to run on after an exception,
+    // unexpectedly some 'startElements' produce a UNO_QUERY_THROW
+    // for XComponent; and yet expect to continue parsing.
+    SAL_WARN("sax", "Unexpected exception from XML parser " << exceptionToString(e));
+    osl::MutexGuard g(maSavedExceptionMutex);
+    if (maSavedException.hasValue())
+    {
+        SAL_INFO("sax.fastparser", "discarding exception, already have one");
+    }
+    else
+    {
+        maSavedException = e;
+    }
+}
+
+bool Entity::hasException()
+{
+    osl::MutexGuard g(maSavedExceptionMutex);
+    return maSavedException.hasValue();
+}
+
+} // namespace
+
+namespace sax_fastparser {
+
+FastSaxParserImpl::FastSaxParserImpl() :
+    m_bIgnoreMissingNSDecl(false),
+    m_bDisableThreadedParser(false),
+    mpTop(nullptr)
+{
+    mxDocumentLocator.set( new FastLocatorImpl( this ) );
+}
+
+FastSaxParserImpl::~FastSaxParserImpl()
+{
+    if( mxDocumentLocator.is() )
+        mxDocumentLocator->dispose();
+}
+
+void FastSaxParserImpl::DefineNamespace( const OString& rPrefix, const OUString& namespaceURL )
+{
+    Entity& rEntity = getEntity();
+    assert(!rEntity.maNamespaceCount.empty()); // need a context!
+
+    sal_uInt32 nOffset = rEntity.maNamespaceCount.top()++;
+    if( rEntity.maNamespaceDefines.size() <= nOffset )
+        rEntity.maNamespaceDefines.resize( rEntity.maNamespaceDefines.size() + 64 );
+
+    rEntity.maNamespaceDefines[nOffset] = NamespaceDefine( rPrefix, GetNamespaceToken( namespaceURL ), namespaceURL );
+}
+
+sal_Int32 FastSaxParserImpl::GetToken( const xmlChar* pName, sal_Int32 nameLen /* = 0 */ )
+{
+    return FastTokenHandlerBase::getTokenFromChars( getEntity(). mxTokenHandler.get(),
+                                                    XML_CAST( pName ), nameLen ); // uses utf-8
+}
+
+sal_Int32 FastSaxParserImpl::GetTokenWithPrefix( const xmlChar* pPrefix, int nPrefixLen, const xmlChar* pName, int nNameLen )
+{
+    sal_Int32 nNamespaceToken = FastToken::DONTKNOW;
+
+    Entity& rEntity = getEntity();
+    if (rEntity.maNamespaceCount.empty())
+        return nNamespaceToken;
+
+    sal_uInt32 nNamespace = rEntity.maNamespaceCount.top();
+    while( nNamespace-- )
+    {
+        const auto & rNamespaceDefine = rEntity.maNamespaceDefines[nNamespace];
+        const OString& rPrefix( rNamespaceDefine.maPrefix );
+        if( (rPrefix.getLength() == nPrefixLen) &&
+            rtl_str_reverseCompare_WithLength(rPrefix.pData->buffer, rPrefix.pData->length, XML_CAST( pPrefix ), nPrefixLen ) == 0 )
+        {
+            nNamespaceToken = rNamespaceDefine.mnToken;
+            break;
+        }
+
+        if( !nNamespace && !m_bIgnoreMissingNSDecl )
+            throw SAXException("No namespace defined for " + OUString(XML_CAST(pPrefix),
+                    nPrefixLen, RTL_TEXTENCODING_UTF8), Reference< XInterface >(), Any());
+    }
+
+    if( nNamespaceToken != FastToken::DONTKNOW )
+    {
+        sal_Int32 nNameToken = GetToken( pName, nNameLen );
+        if( nNameToken != FastToken::DONTKNOW )
+            return nNamespaceToken | nNameToken;
+    }
+
+    return FastToken::DONTKNOW;
+}
+
+sal_Int32 FastSaxParserImpl::GetNamespaceToken( const OUString& rNamespaceURL )
+{
+    NamespaceMap::iterator aIter( maNamespaceMap.find( rNamespaceURL ) );
+    if( aIter != maNamespaceMap.end() )
+        return (*aIter).second;
+    else
+        return FastToken::DONTKNOW;
+}
+
+OUString const & FastSaxParserImpl::GetNamespaceURL( const OString& rPrefix )
+{
+    Entity& rEntity = getEntity();
+    if( !rEntity.maNamespaceCount.empty() )
+    {
+        sal_uInt32 nNamespace = rEntity.maNamespaceCount.top();
+        while( nNamespace-- )
+            if( rEntity.maNamespaceDefines[nNamespace].maPrefix == rPrefix )
+                return rEntity.maNamespaceDefines[nNamespace].maNamespaceURL;
+    }
+
+    throw SAXException("No namespace defined for " + OUString::fromUtf8(rPrefix),
+            Reference< XInterface >(), Any());
+}
+
+sal_Int32 FastSaxParserImpl::GetTokenWithContextNamespace( sal_Int32 nNamespaceToken, const xmlChar* pName, int nNameLen )
+{
+    if( nNamespaceToken != FastToken::DONTKNOW )
+    {
+        sal_Int32 nNameToken = GetToken( pName, nNameLen );
+        if( nNameToken != FastToken::DONTKNOW )
+            return nNamespaceToken | nNameToken;
+    }
+
+    return FastToken::DONTKNOW;
+}
+
+namespace
+{
+    class ParserCleanup
+    {
+    private:
+        FastSaxParserImpl& m_rParser;
+        Entity& m_rEntity;
+        rtl::Reference<ParserThread> m_xParser;
+    public:
+        ParserCleanup(FastSaxParserImpl& rParser, Entity& rEntity)
+            : m_rParser(rParser)
+            , m_rEntity(rEntity)
+        {
+        }
+        ~ParserCleanup()
+        {
+            if (m_rEntity.mpParser)
+            {
+                if (m_rEntity.mpParser->myDoc)
+                    xmlFreeDoc(m_rEntity.mpParser->myDoc);
+                xmlFreeParserCtxt(m_rEntity.mpParser);
+            }
+            joinThread();
+            m_rParser.popEntity();
+        }
+        void setThread(const rtl::Reference<ParserThread> &xParser)
+        {
+            m_xParser = xParser;
+        }
+        void joinThread()
+        {
+            if (m_xParser.is())
+            {
+                rtl::Reference<ParserThread> xToJoin = m_xParser;
+                m_xParser.clear();
+                xToJoin->join();
+            }
+        }
+    };
+}
+/***************
+*
+* parseStream does Parser-startup initializations. The FastSaxParser::parse() method does
+* the file-specific initialization work. (During a parser run, external files may be opened)
+*
+****************/
+void FastSaxParserImpl::parseStream(const InputSource& rStructSource)
+{
+    xmlInitParser();
+
+    // Only one text at one time
+    MutexGuard guard( maMutex );
+
+    pushEntity(maData, rStructSource);
+    Entity& rEntity = getEntity();
+    ParserCleanup aEnsureFree(*this, rEntity);
+
+    // start the document
+    if( rEntity.mxDocumentHandler.is() )
+    {
+        Reference< XLocator > xLoc( mxDocumentLocator.get() );
+        rEntity.mxDocumentHandler->setDocumentLocator( xLoc );
+        rEntity.mxDocumentHandler->startDocument();
+    }
+
+    if (!getenv("SAX_DISABLE_THREADS") && !m_bDisableThreadedParser)
+    {
+        Reference<css::io::XSeekable> xSeekable(rEntity.maStructSource.aInputStream, UNO_QUERY);
+        // available() is not __really__ relevant here, but leave it in as a heuristic for non-seekable streams
+        rEntity.mbEnableThreads = (xSeekable.is() && xSeekable->getLength() > 10000)
+                || (rEntity.maStructSource.aInputStream->available() > 10000);
+    }
+
+    if (rEntity.mbEnableThreads)
+    {
+        rtl::Reference<ParserThread> xParser = new ParserThread(this);
+        xParser->launch();
+        aEnsureFree.setThread(xParser);
+        bool done = false;
+        do {
+            rEntity.maConsumeResume.wait();
+            rEntity.maConsumeResume.reset();
+
+            osl::ResettableMutexGuard aGuard(rEntity.maEventProtector);
+            while (!rEntity.maPendingEvents.empty())
+            {
+                if (rEntity.maPendingEvents.size() <= Entity::mnEventLowWater)
+                    rEntity.maProduceResume.set(); // start producer again
+
+                std::unique_ptr<EventList> xEventList = std::move(rEntity.maPendingEvents.front());
+                rEntity.maPendingEvents.pop();
+                aGuard.clear(); // unlock
+
+                if (!consume(*xEventList))
+                    done = true;
+
+                aGuard.reset(); // lock
+
+                if ( rEntity.maPendingEvents.size() <= Entity::mnEventLowWater )
+                {
+                    aGuard.clear();
+                    for (auto& rEvent : xEventList->maEvents)
+                    {
+                        if (rEvent.mxAttributes.is())
+                        {
+                            rEvent.mxAttributes->clear();
+                            if( rEntity.mxNamespaceHandler.is() )
+                                rEvent.mxDeclAttributes->clear();
+                        }
+                        xEventList->mbIsAttributesEmpty = true;
+                    }
+                    aGuard.reset();
+                }
+
+                rEntity.maUsedEvents.push(std::move(xEventList));
+            }
+        } while (!done);
+        aEnsureFree.joinThread();
+        deleteUsedEvents();
+
+        // callbacks used inside XML_Parse may have caught an exception
+        // No need to lock maSavedExceptionMutex here because parser
+        // thread is joined.
+        if( rEntity.maSavedException.hasValue() )
+            rEntity.throwException( mxDocumentLocator, true );
+    }
+    else
+    {
+        parse();
+    }
+
+    // finish document
+    if( rEntity.mxDocumentHandler.is() )
+    {
+        rEntity.mxDocumentHandler->endDocument();
+    }
+}
+
+void FastSaxParserImpl::setFastDocumentHandler( const Reference< XFastDocumentHandler >& Handler )
+{
+    maData.mxDocumentHandler = Handler;
+}
+
+void FastSaxParserImpl::setTokenHandler( const Reference< XFastTokenHandler >& xHandler )
+{
+    assert( dynamic_cast< FastTokenHandlerBase *>( xHandler.get() ) && "we expect this handler to be a subclass of FastTokenHandlerBase" );
+    maData.mxTokenHandler = dynamic_cast< FastTokenHandlerBase *>( xHandler.get() );
+}
+
+void FastSaxParserImpl::registerNamespace( const OUString& NamespaceURL, sal_Int32 NamespaceToken )
+{
+    if( NamespaceToken < FastToken::NAMESPACE )
+        throw IllegalArgumentException("Invalid namespace token " + OUString::number(NamespaceToken), css::uno::Reference<css::uno::XInterface >(), 0);
+
+    if( GetNamespaceToken( NamespaceURL ) == FastToken::DONTKNOW )
+    {
+        maNamespaceMap[ NamespaceURL ] = NamespaceToken;
+        return;
+    }
+    throw IllegalArgumentException("namespace URL is already registered: " + NamespaceURL, css::uno::Reference<css::uno::XInterface >(), 0);
+}
+
+OUString const & FastSaxParserImpl::getNamespaceURL( const OUString& rPrefix )
+{
+    try
+    {
+        return GetNamespaceURL( OUStringToOString( rPrefix, RTL_TEXTENCODING_UTF8 ) );
+    }
+    catch (const Exception&)
+    {
+    }
+    throw IllegalArgumentException();
+}
+
+void FastSaxParserImpl::setErrorHandler(const Reference< XErrorHandler > & Handler)
+{
+    maData.mxErrorHandler = Handler;
+}
+
+void FastSaxParserImpl::setNamespaceHandler( const Reference< XFastNamespaceHandler >& Handler )
+{
+    maData.mxNamespaceHandler = Handler;
+}
+
+void FastSaxParserImpl::deleteUsedEvents()
+{
+    Entity& rEntity = getEntity();
+    osl::ResettableMutexGuard aGuard(rEntity.maEventProtector);
+
+    while (!rEntity.maUsedEvents.empty())
+    {
+        std::unique_ptr<EventList> xEventList = std::move(rEntity.maUsedEvents.front());
+        rEntity.maUsedEvents.pop();
+
+        aGuard.clear(); // unlock
+
+        xEventList.reset();
+
+        aGuard.reset(); // lock
+    }
+}
+
+void FastSaxParserImpl::produce( bool bForceFlush )
+{
+    Entity& rEntity = getEntity();
+    if (!(bForceFlush ||
+        rEntity.mnProducedEventsSize >= Entity::mnEventListSize))
+        return;
+
+    osl::ResettableMutexGuard aGuard(rEntity.maEventProtector);
+
+    while (rEntity.maPendingEvents.size() >= Entity::mnEventHighWater)
+    { // pause parsing for a bit
+        aGuard.clear(); // unlock
+        rEntity.maProduceResume.wait();
+        rEntity.maProduceResume.reset();
+        aGuard.reset(); // lock
+    }
+
+    rEntity.maPendingEvents.push(std::move(rEntity.mxProducedEvents));
+    assert(rEntity.mxProducedEvents.get() == nullptr);
+
+    aGuard.clear(); // unlock
+
+    rEntity.maConsumeResume.set();
+}
+
+bool FastSaxParserImpl::consume(EventList& rEventList)
+{
+    Entity& rEntity = getEntity();
+    rEventList.mbIsAttributesEmpty = false;
+    for (auto& rEvent : rEventList.maEvents)
+    {
+        switch (rEvent.maType)
+        {
+            case CallbackType::START_ELEMENT:
+                rEntity.startElement( &rEvent );
+                break;
+            case CallbackType::END_ELEMENT:
+                rEntity.endElement();
+                break;
+            case CallbackType::CHARACTERS:
+                rEntity.characters( rEvent.msChars );
+                break;
+            case CallbackType::PROCESSING_INSTRUCTION:
+                rEntity.processingInstruction(
+                    rEvent.msNamespace, rEvent.msElementName ); // ( target, data )
+                break;
+            case CallbackType::DONE:
+                return false;
+            case CallbackType::EXCEPTION:
+                rEntity.throwException( mxDocumentLocator, false );
+                [[fallthrough]]; // avoid unreachable code warning with some compilers
+            default:
+                assert(false);
+                return false;
+        }
+    }
+    return true;
+}
+
+void FastSaxParserImpl::pushEntity(const ParserData& rEntityData,
+        xml::sax::InputSource const& rSource)
+{
+    if (!rSource.aInputStream.is())
+        throw SAXException("No input source", Reference<XInterface>(), Any());
+
+    maEntities.emplace(rEntityData);
+    mpTop = &maEntities.top();
+
+    mpTop->maStructSource = rSource;
+
+    mpTop->maConverter.setInputStream(mpTop->maStructSource.aInputStream);
+    if (!mpTop->maStructSource.sEncoding.isEmpty())
+    {
+        mpTop->maConverter.setEncoding(OUStringToOString(mpTop->maStructSource.sEncoding, RTL_TEXTENCODING_ASCII_US));
+    }
+}
+
+void FastSaxParserImpl::popEntity()
+{
+    maEntities.pop();
+    mpTop = !maEntities.empty() ? &maEntities.top() : nullptr;
+}
+
+// starts parsing with actual parser !
+void FastSaxParserImpl::parse()
+{
+    const int BUFFER_SIZE = 16 * 1024;
+    Sequence< sal_Int8 > seqOut( BUFFER_SIZE );
+
+    Entity& rEntity = getEntity();
+
+    // set all necessary C-Callbacks
+    static xmlSAXHandler callbacks;
+    callbacks.startElementNs = call_callbackStartElement;
+    callbacks.endElementNs = call_callbackEndElement;
+    callbacks.characters = call_callbackCharacters;
+    callbacks.processingInstruction = call_callbackProcessingInstruction;
+    callbacks.initialized = XML_SAX2_MAGIC;
+    int nRead = 0;
+    do
+    {
+        nRead = rEntity.maConverter.readAndConvert( seqOut, BUFFER_SIZE );
+        if( nRead <= 0 )
+        {
+            if( rEntity.mpParser != nullptr )
+            {
+                if( xmlParseChunk( rEntity.mpParser, reinterpret_cast<const char*>(seqOut.getConstArray()), 0, 1 ) != XML_ERR_OK )
+                    rEntity.throwException( mxDocumentLocator, true );
+                if (rEntity.hasException())
+                    rEntity.throwException(mxDocumentLocator, true);
+            }
+            break;
+        }
+
+        bool bContinue = true;
+        if( rEntity.mpParser == nullptr )
+        {
+            // create parser with proper encoding (needs the first chunk of data)
+            rEntity.mpParser = xmlCreatePushParserCtxt( &callbacks, this,
+                reinterpret_cast<const char*>(seqOut.getConstArray()), nRead, nullptr );
+            if( !rEntity.mpParser )
+                throw SAXException("Couldn't create parser", Reference< XInterface >(), Any() );
+
+            // Tell libxml2 parser to decode entities in attribute values.
+            // Also allow XML attribute values which are larger than 10MB, because this used to work
+            // with expat.
+            // coverity[unsafe_xml_parse_config] - entity support is required
+            xmlCtxtUseOptions(rEntity.mpParser, XML_PARSE_NOENT | XML_PARSE_HUGE);
+        }
+        else
+        {
+            bContinue = xmlParseChunk( rEntity.mpParser, reinterpret_cast<const char*>(seqOut.getConstArray()), nRead, 0 )
+                            == XML_ERR_OK;
+        }
+
+        // callbacks used inside XML_Parse may have caught an exception
+        if (!bContinue)
+        {
+            rEntity.throwException( mxDocumentLocator, true );
+        }
+        if (rEntity.hasException())
+        {
+            rEntity.throwException( mxDocumentLocator, true );
+        }
+    } while( nRead > 0 );
+    rEntity.getEvent( CallbackType::DONE );
+    if( rEntity.mbEnableThreads )
+        produce( true );
+}
+
+// The C-Callbacks
+void FastSaxParserImpl::callbackStartElement(const xmlChar *localName , const xmlChar* prefix, const xmlChar* URI,
+    int numNamespaces, const xmlChar** namespaces, int numAttributes, const xmlChar **attributes)
+{
+    if (!pendingCharacters.empty())
+        sendPendingCharacters();
+    Entity& rEntity = getEntity();
+    if( rEntity.maNamespaceCount.empty() )
+    {
+        rEntity.maNamespaceCount.push(0);
+        DefineNamespace( "xml", "http://www.w3.org/XML/1998/namespace");
+    }
+    else
+    {
+        rEntity.maNamespaceCount.push( rEntity.maNamespaceCount.top() );
+    }
+
+    // create attribute map and process namespace instructions
+    Event& rEvent = rEntity.getEvent( CallbackType::START_ELEMENT );
+    bool bIsAttributesEmpty = false;
+    if ( rEntity.mbEnableThreads )
+        bIsAttributesEmpty = rEntity.getEventList().mbIsAttributesEmpty;
+
+    if (rEvent.mxAttributes.is())
+    {
+        if( !bIsAttributesEmpty )
+            rEvent.mxAttributes->clear();
+    }
+    else
+        rEvent.mxAttributes.set(
+                new FastAttributeList( rEntity.mxTokenHandler.get() ) );
+
+    if( rEntity.mxNamespaceHandler.is() )
+    {
+        if (rEvent.mxDeclAttributes.is())
+        {
+            if( !bIsAttributesEmpty )
+                rEvent.mxDeclAttributes->clear();
+        }
+        else
+            rEvent.mxDeclAttributes.set(
+                new FastAttributeList( rEntity.mxTokenHandler.get() ) );
+    }
+
+    OUString sNamespace;
+    sal_Int32 nNamespaceToken = FastToken::DONTKNOW;
+    if (!rEntity.maNamespaceStack.empty())
+    {
+        sNamespace = rEntity.maNamespaceStack.top().msName;
+        nNamespaceToken = rEntity.maNamespaceStack.top().mnToken;
+    }
+
+    try
+    {
+        /*  #158414# Each element may define new namespaces, also for attributes.
+            First, process all namespaces, second, process the attributes after namespaces
+            have been initialized. */
+
+        // #158414# first: get namespaces
+        for (int i = 0; i < numNamespaces * 2; i += 2)
+        {
+            // namespaces[] is (prefix/URI)
+            if( namespaces[ i ] != nullptr )
+            {
+                DefineNamespace( OString( XML_CAST( namespaces[ i ] )),
+                    OUString( XML_CAST( namespaces[ i + 1 ] ), strlen( XML_CAST( namespaces[ i + 1 ] )), RTL_TEXTENCODING_UTF8 ));
+                if( rEntity.mxNamespaceHandler.is() )
+                    rEvent.mxDeclAttributes->addUnknown( OString( XML_CAST( namespaces[ i ] ) ), OString( XML_CAST( namespaces[ i + 1 ] ) ) );
+            }
+            else
+            {
+                // default namespace
+                sNamespace = OUString( XML_CAST( namespaces[ i + 1 ] ), strlen( XML_CAST( namespaces[ i + 1 ] )), RTL_TEXTENCODING_UTF8 );
+                nNamespaceToken = GetNamespaceToken( sNamespace );
+                if( rEntity.mxNamespaceHandler.is() )
+                    rEvent.mxDeclAttributes->addUnknown( "", OString( XML_CAST( namespaces[ i + 1 ] ) ) );
+            }
+        }
+
+        if ( rEntity.mxTokenHandler.is() )
+        {
+            // #158414# second: fill attribute list with other attributes
+            rEvent.mxAttributes->reserve( numAttributes );
+            for (int i = 0; i < numAttributes * 5; i += 5)
+            {
+                // attributes[] is ( localname / prefix / nsURI / valueBegin / valueEnd )
+                if( attributes[ i + 1 ] != nullptr )
+                {
+                    sal_Int32 nAttributeToken = GetTokenWithPrefix( attributes[ i + 1 ], strlen( XML_CAST( attributes[ i + 1 ] )), attributes[ i ], strlen( XML_CAST( attributes[ i ] )));
+                    if( nAttributeToken != FastToken::DONTKNOW )
+                        rEvent.mxAttributes->add( nAttributeToken, XML_CAST( attributes[ i + 3 ] ), attributes[ i + 4 ] - attributes[ i + 3 ] );
+                    else
+                        addUnknownElementWithPrefix(attributes, i, rEvent.mxAttributes);
+                }
+                else
+                {
+                    sal_Int32 nAttributeToken = GetToken( attributes[ i ], strlen( XML_CAST( attributes[ i ] )));
+                    if( nAttributeToken != FastToken::DONTKNOW )
+                        rEvent.mxAttributes->add( nAttributeToken, XML_CAST( attributes[ i + 3 ] ), attributes[ i + 4 ] - attributes[ i + 3 ] );
+                    else
+                    {
+                        SAL_WARN("xmloff", "unknown attribute " << XML_CAST( attributes[ i ] ) << "=" <<
+                            OString( XML_CAST( attributes[ i + 3 ] ), attributes[ i + 4 ] - attributes[ i + 3 ] ));
+                        rEvent.mxAttributes->addUnknown( XML_CAST( attributes[ i ] ),
+                            OString( XML_CAST( attributes[ i + 3 ] ), attributes[ i + 4 ] - attributes[ i + 3 ] ));
+                    }
+                }
+            }
+
+            if( prefix != nullptr )
+                rEvent.mnElementToken = GetTokenWithPrefix( prefix, strlen( XML_CAST( prefix )), localName, strlen( XML_CAST( localName )));
+            else if( !sNamespace.isEmpty() )
+                rEvent.mnElementToken = GetTokenWithContextNamespace( nNamespaceToken, localName, strlen( XML_CAST( localName )));
+            else
+                rEvent.mnElementToken = GetToken( localName, strlen( XML_CAST( localName )));
+        }
+        else
+        {
+            for (int i = 0; i < numAttributes * 5; i += 5)
+            {
+                if( attributes[ i + 1 ] != nullptr )
+                    addUnknownElementWithPrefix(attributes, i, rEvent.mxAttributes);
+                else
+                    rEvent.mxAttributes->addUnknown( XML_CAST( attributes[ i ] ),
+                            OString( XML_CAST( attributes[ i + 3 ] ), attributes[ i + 4 ] - attributes[ i + 3 ] ));
+            }
+
+            rEvent.mnElementToken = FastToken::DONTKNOW;
+        }
+
+        if( rEvent.mnElementToken == FastToken::DONTKNOW )
+        {
+            OUString aElementPrefix;
+            if( prefix != nullptr )
+            {
+                if ( !m_bIgnoreMissingNSDecl || URI != nullptr )
+                    sNamespace = OUString( XML_CAST( URI ), strlen( XML_CAST( URI )), RTL_TEXTENCODING_UTF8 );
+                else
+                    sNamespace.clear();
+                nNamespaceToken = GetNamespaceToken( sNamespace );
+                aElementPrefix = OUString( XML_CAST( prefix ), strlen( XML_CAST( prefix )), RTL_TEXTENCODING_UTF8 );
+            }
+            const OUString& rElementLocalName = OUString( XML_CAST( localName ), strlen( XML_CAST( localName )), RTL_TEXTENCODING_UTF8 );
+            rEvent.msNamespace = sNamespace;
+            rEvent.msElementName = (aElementPrefix.isEmpty())? rElementLocalName : aElementPrefix + ":" + rElementLocalName;
+        }
+        else // token is always preferred.
+            rEvent.msElementName.clear();
+
+        rEntity.maNamespaceStack.push( NameWithToken(sNamespace, nNamespaceToken) );
+        if (rEntity.mbEnableThreads)
+            produce();
+        else
+        {
+            SAL_INFO("sax.fastparser", " startElement line " << mxDocumentLocator->getLineNumber() << " column " << mxDocumentLocator->getColumnNumber() << " " << ( prefix ? XML_CAST(prefix) : "(null)" ) << ":" << localName);
+            rEntity.startElement( &rEvent );
+        }
+    }
+    catch (...)
+    {
+        rEntity.saveException( ::cppu::getCaughtException() );
+    }
+}
+
+void FastSaxParserImpl::addUnknownElementWithPrefix(const xmlChar **attributes, int i, rtl::Reference< FastAttributeList > const & xAttributes)
+{
+    OUString aNamespaceURI;
+    if ( !m_bIgnoreMissingNSDecl || attributes[i + 2] != nullptr )
+        aNamespaceURI = OUString( XML_CAST( attributes[ i + 2 ] ), strlen( XML_CAST( attributes[ i + 2 ] )), RTL_TEXTENCODING_UTF8 );
+    const OString& rPrefix = OString( XML_CAST( attributes[ i + 1 ] ));
+    const OString& rLocalName = OString( XML_CAST( attributes[ i ] ));
+    OString aQualifiedName = (rPrefix.isEmpty())? rLocalName : rPrefix + ":" + rLocalName;
+    xAttributes->addUnknown( aNamespaceURI, aQualifiedName,
+        OString( XML_CAST( attributes[ i + 3 ] ), attributes[ i + 4 ] - attributes[ i + 3 ] ));
+    SAL_WARN("xmloff", "unknown element " << aQualifiedName << " " << aNamespaceURI);
+}
+
+void FastSaxParserImpl::callbackEndElement()
+{
+    if (!pendingCharacters.empty())
+        sendPendingCharacters();
+    Entity& rEntity = getEntity();
+    SAL_WARN_IF(rEntity.maNamespaceCount.empty(), "sax", "Empty NamespaceCount");
+    if( !rEntity.maNamespaceCount.empty() )
+        rEntity.maNamespaceCount.pop();
+
+    SAL_WARN_IF(rEntity.maNamespaceStack.empty(), "sax", "Empty NamespaceStack");
+    if( !rEntity.maNamespaceStack.empty() )
+        rEntity.maNamespaceStack.pop();
+
+    rEntity.getEvent( CallbackType::END_ELEMENT );
+    if (rEntity.mbEnableThreads)
+        produce();
+    else
+        rEntity.endElement();
+}
+
+void FastSaxParserImpl::callbackCharacters( const xmlChar* s, int nLen )
+{
+    // SAX interface allows that the characters callback splits content of one XML node
+    // (e.g. because there's an entity that needs decoding), however for consumers it's
+    // simpler FastSaxParser's character callback provides the whole string at once,
+    // so merge data from possible multiple calls and send them at once (before the element
+    // ends or another one starts).
+    //
+    // We use a std::vector<char> to avoid calling into the OUString constructor more than once when
+    // we have multiple callbackCharacters() calls that we have to merge, which happens surprisingly
+    // often in writer documents.
+    int nOriginalLen = pendingCharacters.size();
+    pendingCharacters.resize(nOriginalLen + nLen);
+    memcpy(pendingCharacters.data() + nOriginalLen, s, nLen);
+}
+
+void FastSaxParserImpl::sendPendingCharacters()
+{
+    Entity& rEntity = getEntity();
+    OUString sChars( pendingCharacters.data(), pendingCharacters.size(), RTL_TEXTENCODING_UTF8 );
+    if (rEntity.mbEnableThreads)
+    {
+        Event& rEvent = rEntity.getEvent( CallbackType::CHARACTERS );
+        rEvent.msChars = sChars;
+        produce();
+    }
+    else
+        rEntity.characters( sChars );
+    pendingCharacters.resize(0);
+}
+
+void FastSaxParserImpl::callbackProcessingInstruction( const xmlChar *target, const xmlChar *data )
+{
+    if (!pendingCharacters.empty())
+        sendPendingCharacters();
+    Entity& rEntity = getEntity();
+    Event& rEvent = rEntity.getEvent( CallbackType::PROCESSING_INSTRUCTION );
+
+    // This event is very rare, so no need to waste extra space for this
+    // Using namespace and element strings to be target and data in that order.
+    rEvent.msNamespace = OUString( XML_CAST( target ), strlen( XML_CAST( target ) ), RTL_TEXTENCODING_UTF8 );
+    if ( data != nullptr )
+        rEvent.msElementName = OUString( XML_CAST( data ), strlen( XML_CAST( data ) ), RTL_TEXTENCODING_UTF8 );
+    else
+        rEvent.msElementName.clear();
+
+    if (rEntity.mbEnableThreads)
+        produce();
+    else
+        rEntity.processingInstruction( rEvent.msNamespace, rEvent.msElementName );
+}
+
+FastSaxParser::FastSaxParser() : mpImpl(new FastSaxParserImpl) {}
+
+FastSaxParser::~FastSaxParser()
+{
+}
+
+void SAL_CALL
+FastSaxParser::initialize(css::uno::Sequence< css::uno::Any > const& rArguments)
+{
+    if (!rArguments.hasElements())
+        return;
+
+    OUString str;
+    if ( !(rArguments[0] >>= str) )
+        throw IllegalArgumentException();
+
+    if ( str == "IgnoreMissingNSDecl" )
+        mpImpl->m_bIgnoreMissingNSDecl = true;
+    else if ( str == "DoSmeplease" )
+        ; //just ignore as this is already immune to billion laughs
+    else if ( str == "DisableThreadedParser" )
+        mpImpl->m_bDisableThreadedParser = true;
+    else
+        throw IllegalArgumentException();
+
+}
+
+void FastSaxParser::parseStream( const xml::sax::InputSource& aInputSource )
+{
+    mpImpl->parseStream(aInputSource);
+}
+
+void FastSaxParser::setFastDocumentHandler( const uno::Reference<xml::sax::XFastDocumentHandler>& Handler )
+{
+    mpImpl->setFastDocumentHandler(Handler);
+}
+
+void FastSaxParser::setTokenHandler( const uno::Reference<xml::sax::XFastTokenHandler>& Handler )
+{
+    mpImpl->setTokenHandler(Handler);
+}
+
+void FastSaxParser::registerNamespace( const OUString& NamespaceURL, sal_Int32 NamespaceToken )
+{
+    mpImpl->registerNamespace(NamespaceURL, NamespaceToken);
+}
+
+OUString FastSaxParser::getNamespaceURL( const OUString& rPrefix )
+{
+    return mpImpl->getNamespaceURL(rPrefix);
+}
+
+void FastSaxParser::setErrorHandler( const uno::Reference< xml::sax::XErrorHandler >& Handler )
+{
+    mpImpl->setErrorHandler(Handler);
+}
+
+void FastSaxParser::setEntityResolver( const uno::Reference< xml::sax::XEntityResolver >& )
+{
+    // not implemented
+}
+
+void FastSaxParser::setLocale( const lang::Locale& )
+{
+    // not implemented
+}
+
+void FastSaxParser::setNamespaceHandler( const uno::Reference< css::xml::sax::XFastNamespaceHandler >& Handler)
+{
+    mpImpl->setNamespaceHandler(Handler);
+}
+
+OUString FastSaxParser::getImplementationName()
+{
+    return "com.sun.star.comp.extensions.xml.sax.FastParser";
+}
+
+sal_Bool FastSaxParser::supportsService( const OUString& ServiceName )
+{
+    return cppu::supportsService(this, ServiceName);
+}
+
+uno::Sequence<OUString> FastSaxParser::getSupportedServiceNames()
+{
+    return { "com.sun.star.xml.sax.FastParser" };
+}
+
+} // namespace sax_fastparser
+
+extern "C" SAL_DLLPUBLIC_EXPORT css::uno::XInterface *
+com_sun_star_comp_extensions_xml_sax_FastParser_get_implementation(
+    css::uno::XComponentContext *,
+    css::uno::Sequence<css::uno::Any> const &)
+{
+    return cppu::acquire(new FastSaxParser);
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sax/source/fastparser/legacyfastparser.cxx b/sax/source/fastparser/legacyfastparser.cxx
new file mode 100644
index 000000000..bb1045970
--- /dev/null
+++ b/sax/source/fastparser/legacyfastparser.cxx
@@ -0,0 +1,378 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <com/sun/star/lang/XServiceInfo.hpp>
+#include <com/sun/star/xml/sax/XParser.hpp>
+#include <com/sun/star/xml/sax/FastParser.hpp>
+#include <com/sun/star/lang/XInitialization.hpp>
+#include <com/sun/star/beans/Pair.hpp>
+#include <comphelper/attributelist.hxx>
+#include <cppuhelper/supportsservice.hxx>
+#include <comphelper/processfactory.hxx>
+#include <rtl/ref.hxx>
+#include <memory>
+#include <vector>
+
+using namespace std;
+using namespace ::cppu;
+using namespace css;
+using namespace uno;
+using namespace lang;
+using namespace xml::sax;
+using namespace io;
+
+namespace {
+
+class NamespaceHandler : public WeakImplHelper< XFastNamespaceHandler >
+{
+private:
+    struct NamespaceDefine
+    {
+        OUString    m_aPrefix;
+        OUString    m_aNamespaceURI;
+
+        NamespaceDefine( const OUString& rPrefix, const OUString& rNamespaceURI ) : m_aPrefix( rPrefix ), m_aNamespaceURI( rNamespaceURI ) {}
+    };
+    vector< unique_ptr< NamespaceDefine > > m_aNamespaceDefines;
+
+public:
+    NamespaceHandler();
+    void addNSDeclAttributes( rtl::Reference < comphelper::AttributeList > const & rAttrList );
+
+    //XFastNamespaceHandler
+    virtual void SAL_CALL registerNamespace( const OUString& rNamespacePrefix, const OUString& rNamespaceURI ) override;
+    virtual OUString SAL_CALL getNamespaceURI( const OUString& rNamespacePrefix ) override;
+};
+
+NamespaceHandler::NamespaceHandler()
+{
+}
+
+void NamespaceHandler::addNSDeclAttributes( rtl::Reference < comphelper::AttributeList > const & rAttrList )
+{
+    for(const auto& aNamespaceDefine : m_aNamespaceDefines)
+    {
+        OUString& rPrefix = aNamespaceDefine->m_aPrefix;
+        OUString& rNamespaceURI = aNamespaceDefine->m_aNamespaceURI;
+        OUString sDecl;
+        if ( rPrefix.isEmpty() )
+            sDecl = "xmlns";
+        else
+            sDecl = "xmlns:" + rPrefix;
+        rAttrList->AddAttribute( sDecl, "CDATA", rNamespaceURI );
+    }
+    m_aNamespaceDefines.clear();
+}
+
+void NamespaceHandler::registerNamespace( const OUString& rNamespacePrefix, const OUString& rNamespaceURI )
+{
+    m_aNamespaceDefines.push_back( std::make_unique<NamespaceDefine>(
+                                    rNamespacePrefix, rNamespaceURI) );
+}
+
+OUString NamespaceHandler::getNamespaceURI( const OUString&/* rNamespacePrefix */ )
+{
+    return OUString();
+}
+
+class SaxLegacyFastParser : public WeakImplHelper< XInitialization, XServiceInfo, XParser >
+{
+private:
+    rtl::Reference< NamespaceHandler > m_aNamespaceHandler;
+public:
+    SaxLegacyFastParser();
+
+// css::lang::XInitialization:
+    virtual void SAL_CALL initialize(css::uno::Sequence<css::uno::Any> const& rArguments) override;
+
+// The SAX-Parser-Interface
+    virtual void SAL_CALL parseStream(  const InputSource& structSource) override;
+    virtual void SAL_CALL setDocumentHandler(const Reference< XDocumentHandler > & xHandler) override;
+    virtual void SAL_CALL setErrorHandler(const Reference< XErrorHandler > & xHandler) override;
+    virtual void SAL_CALL setDTDHandler(const Reference < XDTDHandler > & xHandler) override;
+    virtual void SAL_CALL setEntityResolver(const Reference<  XEntityResolver >& xResolver) override;
+    virtual void SAL_CALL setLocale( const Locale &locale ) override;
+
+// XServiceInfo
+    OUString SAL_CALL getImplementationName() override;
+    Sequence< OUString > SAL_CALL getSupportedServiceNames() override;
+    sal_Bool SAL_CALL supportsService(const OUString& ServiceName) override;
+
+private:
+    Reference< XFastParser > m_xParser;
+    Reference< XDocumentHandler > m_xDocumentHandler;
+    Reference< XFastTokenHandler > m_xTokenHandler;
+
+};
+
+
+class CallbackDocumentHandler : public WeakImplHelper< XFastDocumentHandler >
+{
+private:
+    Reference< XDocumentHandler > m_xDocumentHandler;
+    Reference< XFastTokenHandler > m_xTokenHandler;
+    rtl::Reference< NamespaceHandler > m_aNamespaceHandler;
+    OUString getNamespacePrefixFromToken( sal_Int32 nToken );
+    OUString getNameFromToken( sal_Int32 nToken );
+
+    static const OUString aDefaultNamespace;
+    static const OUString aNamespaceSeparator;
+
+public:
+    CallbackDocumentHandler( Reference< XDocumentHandler > const & xDocumentHandler,
+                             rtl::Reference< NamespaceHandler > const & rNamespaceHandler,
+                             Reference< XFastTokenHandler > const & xTokenHandler);
+
+    // XFastDocumentHandler
+    virtual void SAL_CALL startDocument() override;
+    virtual void SAL_CALL endDocument() override;
+    virtual void SAL_CALL processingInstruction( const OUString& rTarget, const OUString& rData ) override;
+    virtual void SAL_CALL setDocumentLocator( const Reference< XLocator >& xLocator ) override;
+
+    // XFastContextHandler
+    virtual void SAL_CALL startFastElement( sal_Int32 nElement, const Reference< XFastAttributeList >& Attribs ) override;
+    virtual void SAL_CALL startUnknownElement( const OUString& Namespace, const OUString& Name, const Reference< XFastAttributeList >& Attribs ) override;
+    virtual void SAL_CALL endFastElement( sal_Int32 Element ) override;
+    virtual void SAL_CALL endUnknownElement( const OUString& Namespace, const OUString& Name ) override;
+    virtual Reference< XFastContextHandler > SAL_CALL createFastChildContext( sal_Int32 nElement, const Reference< XFastAttributeList >& Attribs ) override;
+    virtual Reference< XFastContextHandler > SAL_CALL createUnknownChildContext( const OUString& Namespace, const OUString& Name, const Reference< XFastAttributeList >& Attribs ) override;
+    virtual void SAL_CALL characters( const OUString& aChars ) override;
+
+};
+
+const OUString CallbackDocumentHandler::aDefaultNamespace = OUString("");
+const OUString CallbackDocumentHandler::aNamespaceSeparator = OUString(":");
+
+OUString CallbackDocumentHandler::getNamespacePrefixFromToken( sal_Int32 nToken )
+{
+    if ( ( nToken & 0xffff0000 ) != 0 )
+    {
+        Sequence< sal_Int8 > aSeq = m_xTokenHandler->getUTF8Identifier( nToken & 0xffff0000 );
+        return OUString( reinterpret_cast< const char* >(
+                        aSeq.getConstArray() ), aSeq.getLength(), RTL_TEXTENCODING_UTF8 );
+    }
+    else
+        return OUString();
+}
+
+OUString CallbackDocumentHandler::getNameFromToken( sal_Int32 nToken )
+{
+    Sequence< sal_Int8 > aSeq = m_xTokenHandler->getUTF8Identifier( nToken & 0xffff );
+    return OUString( reinterpret_cast< const char* >(
+                    aSeq.getConstArray() ), aSeq.getLength(), RTL_TEXTENCODING_UTF8 );
+}
+
+CallbackDocumentHandler::CallbackDocumentHandler( Reference< XDocumentHandler > const & xDocumentHandler,
+                                                  rtl::Reference< NamespaceHandler > const & rNamespaceHandler,
+                                                  Reference< XFastTokenHandler > const & xTokenHandler)
+{
+   m_xDocumentHandler.set( xDocumentHandler );
+   m_aNamespaceHandler.set( rNamespaceHandler.get() );
+   m_xTokenHandler.set( xTokenHandler );
+}
+
+void SAL_CALL CallbackDocumentHandler::startDocument()
+{
+    if ( m_xDocumentHandler.is() )
+        m_xDocumentHandler->startDocument();
+}
+
+void SAL_CALL CallbackDocumentHandler::endDocument()
+{
+    if ( m_xDocumentHandler.is() )
+        m_xDocumentHandler->endDocument();
+}
+
+void SAL_CALL CallbackDocumentHandler::processingInstruction( const OUString& rTarget, const OUString& rData )
+{
+    if ( m_xDocumentHandler.is() )
+        m_xDocumentHandler->processingInstruction( rTarget, rData );
+}
+
+void SAL_CALL CallbackDocumentHandler::setDocumentLocator( const Reference< XLocator >& xLocator )
+{
+    if ( m_xDocumentHandler.is() )
+        m_xDocumentHandler->setDocumentLocator( xLocator );
+}
+
+void SAL_CALL CallbackDocumentHandler::startFastElement( sal_Int32 nElement , const Reference< XFastAttributeList >& Attribs  )
+{
+    const OUString& rPrefix = CallbackDocumentHandler::getNamespacePrefixFromToken( nElement );
+    const OUString& rLocalName = CallbackDocumentHandler::getNameFromToken( nElement );
+    startUnknownElement( aDefaultNamespace, (rPrefix.isEmpty())? rLocalName : rPrefix + aNamespaceSeparator + rLocalName, Attribs );
+}
+
+void SAL_CALL CallbackDocumentHandler::startUnknownElement( const OUString& /*Namespace*/, const OUString& Name, const Reference< XFastAttributeList >& Attribs  )
+{
+    if ( !m_xDocumentHandler.is() )
+        return;
+
+    rtl::Reference < comphelper::AttributeList > rAttrList = new comphelper::AttributeList;
+    m_aNamespaceHandler->addNSDeclAttributes( rAttrList );
+
+    const Sequence< xml::FastAttribute > fastAttribs = Attribs->getFastAttributes();
+    for (const auto& rAttr : fastAttribs)
+    {
+        const OUString& rAttrValue = rAttr.Value;
+        sal_Int32 nToken = rAttr.Token;
+        const OUString& rAttrNamespacePrefix = CallbackDocumentHandler::getNamespacePrefixFromToken( nToken );
+        OUString sAttrName = CallbackDocumentHandler::getNameFromToken( nToken );
+        if ( !rAttrNamespacePrefix.isEmpty() )
+            sAttrName = rAttrNamespacePrefix + aNamespaceSeparator + sAttrName;
+
+        rAttrList->AddAttribute( sAttrName, "CDATA", rAttrValue );
+    }
+
+    const Sequence< xml::Attribute > unknownAttribs = Attribs->getUnknownAttributes();
+    for (const auto& rAttr : unknownAttribs)
+    {
+        const OUString& rAttrValue = rAttr.Value;
+        const OUString& rAttrName = rAttr.Name;
+
+        rAttrList->AddAttribute( rAttrName, "CDATA", rAttrValue );
+    }
+    m_xDocumentHandler->startElement( Name, rAttrList.get() );
+}
+
+void SAL_CALL CallbackDocumentHandler::endFastElement( sal_Int32 nElement )
+{
+    const OUString& rPrefix = CallbackDocumentHandler::getNamespacePrefixFromToken( nElement );
+    const OUString& rLocalName = CallbackDocumentHandler::getNameFromToken( nElement );
+    endUnknownElement( aDefaultNamespace, (rPrefix.isEmpty())? rLocalName : rPrefix + aNamespaceSeparator + rLocalName );
+}
+
+
+void SAL_CALL CallbackDocumentHandler::endUnknownElement( const OUString& /*Namespace*/, const OUString& Name )
+{
+    if ( m_xDocumentHandler.is() )
+    {
+        m_xDocumentHandler->endElement( Name );
+    }
+}
+
+Reference< XFastContextHandler > SAL_CALL CallbackDocumentHandler::createFastChildContext( sal_Int32/* nElement */, const Reference< XFastAttributeList >&/* Attribs */ )
+{
+    return this;
+}
+
+
+Reference< XFastContextHandler > SAL_CALL CallbackDocumentHandler::createUnknownChildContext( const OUString&/* Namespace */, const OUString&/* Name */, const Reference< XFastAttributeList >&/* Attribs */ )
+{
+    return this;
+}
+
+void SAL_CALL CallbackDocumentHandler::characters( const OUString& aChars )
+{
+    if ( m_xDocumentHandler.is() )
+        m_xDocumentHandler->characters( aChars );
+}
+
+SaxLegacyFastParser::SaxLegacyFastParser( ) : m_aNamespaceHandler( new NamespaceHandler ),
+  m_xParser(FastParser::create(::comphelper::getProcessComponentContext() ))
+{
+    m_xParser->setNamespaceHandler( m_aNamespaceHandler.get() );
+}
+
+void SAL_CALL SaxLegacyFastParser::initialize(Sequence< Any > const& rArguments )
+{
+    if (!rArguments.hasElements())
+        return;
+
+    Reference< XFastTokenHandler > xTokenHandler;
+    OUString str;
+    if ( ( rArguments[0] >>= xTokenHandler ) && xTokenHandler.is() )
+    {
+        m_xTokenHandler.set( xTokenHandler );
+    }
+    else if ( ( rArguments[0] >>= str ) && "registerNamespaces" == str )
+    {
+        css::beans::Pair< OUString, sal_Int32 > rPair;
+        for (sal_Int32 i = 1; i < rArguments.getLength(); i++ )
+        {
+            rArguments[i] >>= rPair;
+            m_xParser->registerNamespace( rPair.First, rPair.Second );
+        }
+    }
+    else
+    {
+        uno::Reference<lang::XInitialization> const xInit(m_xParser,
+                        uno::UNO_QUERY_THROW);
+        xInit->initialize( rArguments );
+    }
+}
+
+void SaxLegacyFastParser::parseStream( const InputSource& structSource )
+{
+    m_xParser->setFastDocumentHandler( new CallbackDocumentHandler( m_xDocumentHandler.get(),
+                                       m_aNamespaceHandler.get(), m_xTokenHandler.get() ) );
+    m_xParser->setTokenHandler( m_xTokenHandler );
+    m_xParser->parseStream( structSource );
+}
+
+void SaxLegacyFastParser::setDocumentHandler( const Reference< XDocumentHandler > & xHandler )
+{
+    m_xDocumentHandler = xHandler;
+}
+
+void SaxLegacyFastParser::setErrorHandler( const Reference< XErrorHandler > & xHandler )
+{
+    m_xParser->setErrorHandler( xHandler );
+}
+
+void SaxLegacyFastParser::setDTDHandler( const Reference < XDTDHandler > &/* xHandler */ )
+{
+
+}
+
+void SaxLegacyFastParser::setEntityResolver( const Reference<  XEntityResolver >& xResolver )
+{
+    m_xParser->setEntityResolver( xResolver );
+}
+
+void SaxLegacyFastParser::setLocale( const Locale &locale )
+{
+    m_xParser->setLocale( locale );
+}
+
+OUString SaxLegacyFastParser::getImplementationName()
+{
+    return "com.sun.star.comp.extensions.xml.sax.LegacyFastParser";
+}
+
+sal_Bool SaxLegacyFastParser::supportsService(const OUString& ServiceName)
+{
+    return cppu::supportsService(this, ServiceName);
+}
+
+Sequence< OUString > SaxLegacyFastParser::getSupportedServiceNames()
+{
+    return { "com.sun.star.xml.sax.LegacyFastParser" };
+}
+
+} //namespace
+
+extern "C" SAL_DLLPUBLIC_EXPORT css::uno::XInterface *
+com_sun_star_comp_extensions_xml_sax_LegacyFastParser_get_implementation(
+    css::uno::XComponentContext *,
+    css::uno::Sequence<css::uno::Any> const &)
+{
+    return cppu::acquire(new SaxLegacyFastParser);
+}
+
+ /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sax/source/tools/CachedOutputStream.hxx b/sax/source/tools/CachedOutputStream.hxx
new file mode 100644
index 000000000..c3f442f9d
--- /dev/null
+++ b/sax/source/tools/CachedOutputStream.hxx
@@ -0,0 +1,118 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+
+#ifndef INCLUDED_SAX_SOURCE_TOOLS_CACHEDOUTPUTSTREAM_HXX
+#define INCLUDED_SAX_SOURCE_TOOLS_CACHEDOUTPUTSTREAM_HXX
+
+#include <sal/types.h>
+
+#include <com/sun/star/io/XOutputStream.hpp>
+#include <com/sun/star/uno/Sequence.hxx>
+
+#include <cstring>
+#include <memory>
+
+namespace sax_fastparser {
+
+class ForMergeBase
+{
+public:
+    virtual ~ForMergeBase() {}
+    virtual void append( const css::uno::Sequence<sal_Int8>& rWhat ) = 0;
+};
+
+class CachedOutputStream
+{
+    /// When buffer hits this size, it's written to mxOutputStream
+    static const sal_Int32 mnMaximumSize = 0x10000;
+
+    /// ForMerge structure is used for sorting elements in Writer
+    std::shared_ptr< ForMergeBase > mpForMerge;
+    const css::uno::Sequence<sal_Int8> mpCache;
+    /// Output stream, usually writing data into files.
+    css::uno::Reference< css::io::XOutputStream > mxOutputStream;
+    uno_Sequence *pSeq;
+    sal_Int32 mnCacheWrittenSize;
+    bool mbWriteToOutStream;
+
+public:
+    CachedOutputStream() : mpCache(mnMaximumSize)
+                         , pSeq(mpCache.get())
+                         , mnCacheWrittenSize(0)
+                         , mbWriteToOutStream(true)
+    {}
+
+    const css::uno::Reference< css::io::XOutputStream >& getOutputStream() const
+    {
+        return mxOutputStream;
+    }
+
+    void setOutputStream( const css::uno::Reference< css::io::XOutputStream >& xOutputStream )
+    {
+        mxOutputStream = xOutputStream;
+    }
+
+    void setOutput( std::shared_ptr< ForMergeBase > pForMerge )
+    {
+        flush();
+        mbWriteToOutStream = false;
+        mpForMerge = pForMerge;
+    }
+
+    void resetOutputToStream()
+    {
+        flush();
+        mbWriteToOutStream = true;
+        mpForMerge.reset();
+    }
+
+    /// cache string and if limit is hit, flush
+    void writeBytes( const sal_Int8* pStr, sal_Int32 nLen )
+    {
+        // Write when the buffer gets big enough
+        if (mnCacheWrittenSize + nLen > mnMaximumSize)
+        {
+            flush();
+
+            // Writer does some elements sorting, so it can accumulate
+            // pretty big strings in FastSaxSerializer::ForMerge.
+            // In that case, just flush data and write immediately.
+            if (nLen > mnMaximumSize)
+            {
+                if (mbWriteToOutStream)
+                    mxOutputStream->writeBytes( css::uno::Sequence<sal_Int8>(pStr, nLen) );
+                else
+                    mpForMerge->append( css::uno::Sequence<sal_Int8>(pStr, nLen) );
+                return;
+            }
+        }
+
+        memcpy(pSeq->elements + mnCacheWrittenSize, pStr, nLen);
+        mnCacheWrittenSize += nLen;
+    }
+
+    /// immediately write buffer into mxOutputStream and clear
+    void flush()
+    {
+        // resize the Sequence to written size
+        pSeq->nElements = mnCacheWrittenSize;
+        if (mbWriteToOutStream)
+            mxOutputStream->writeBytes( mpCache );
+        else
+            mpForMerge->append( mpCache );
+        // and next time write to the beginning
+        mnCacheWrittenSize = 0;
+    }
+};
+
+}
+
+#endif
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sax/source/tools/converter.cxx b/sax/source/tools/converter.cxx
new file mode 100644
index 000000000..ac6eba928
--- /dev/null
+++ b/sax/source/tools/converter.cxx
@@ -0,0 +1,2448 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <sax/tools/converter.hxx>
+
+#include <com/sun/star/i18n/UnicodeType.hpp>
+#include <com/sun/star/util/DateTime.hpp>
+#include <com/sun/star/util/Date.hpp>
+#include <com/sun/star/util/Duration.hpp>
+#include <com/sun/star/util/Time.hpp>
+#include <optional>
+
+#include <rtl/ustrbuf.hxx>
+#include <rtl/math.hxx>
+#include <sal/log.hxx>
+#include <osl/diagnose.h>
+
+#include <algorithm>
+#include <string_view>
+
+using namespace com::sun::star;
+using namespace com::sun::star::uno;
+using namespace com::sun::star::util;
+using namespace ::com::sun::star::i18n;
+
+
+namespace sax {
+
+static const char* const gpsMM = "mm";
+static const char* const gpsCM = "cm";
+static const char* const gpsPT = "pt";
+static const char* const gpsINCH = "in";
+static const char* const gpsPC = "pc";
+
+const sal_Int8 XML_MAXDIGITSCOUNT_TIME = 14;
+
+/** convert string to measure using optional min and max values*/
+bool Converter::convertMeasure( sal_Int32& rValue,
+                                const OUString& rString,
+                                sal_Int16 nTargetUnit /* = MeasureUnit::MM_100TH */,
+                                sal_Int32 nMin /* = SAL_MIN_INT32 */,
+                                sal_Int32 nMax /* = SAL_MAX_INT32 */ )
+{
+    bool bNeg = false;
+    double nVal = 0;
+
+    sal_Int32 nPos = 0;
+    sal_Int32 const nLen = rString.getLength();
+
+    // skip white space
+    while( (nPos < nLen) && (rString[nPos] <= ' ') )
+        nPos++;
+
+    if( nPos < nLen && '-' == rString[nPos] )
+    {
+        bNeg = true;
+        nPos++;
+    }
+
+    // get number
+    while( nPos < nLen &&
+           '0' <= rString[nPos] &&
+           '9' >= rString[nPos] )
+    {
+        // TODO: check overflow!
+        nVal *= 10;
+        nVal += (rString[nPos] - '0');
+        nPos++;
+    }
+    if( nPos < nLen && '.' == rString[nPos] )
+    {
+        nPos++;
+        double nDiv = 1.;
+
+        while( nPos < nLen &&
+               '0' <= rString[nPos] &&
+               '9' >= rString[nPos] )
+        {
+            // TODO: check overflow!
+            nDiv *= 10;
+            nVal += ( static_cast<double>(rString[nPos] - '0') / nDiv );
+            nPos++;
+        }
+    }
+
+    // skip white space
+    while( (nPos < nLen) && (rString[nPos] <= ' ') )
+        nPos++;
+
+    if( nPos < nLen )
+    {
+
+        if( MeasureUnit::PERCENT == nTargetUnit )
+        {
+            if( '%' != rString[nPos] )
+                return false;
+        }
+        else if( MeasureUnit::PIXEL == nTargetUnit )
+        {
+            if( nPos + 1 >= nLen ||
+                ('p' != rString[nPos] &&
+                 'P' != rString[nPos])||
+                ('x' != rString[nPos+1] &&
+                 'X' != rString[nPos+1]) )
+                return false;
+        }
+        else
+        {
+            OSL_ENSURE( MeasureUnit::TWIP == nTargetUnit || MeasureUnit::POINT == nTargetUnit ||
+                        MeasureUnit::MM_100TH == nTargetUnit || MeasureUnit::MM_10TH == nTargetUnit ||
+                        MeasureUnit::PIXEL == nTargetUnit, "unit is not supported");
+            const char *aCmpsL[3] = { nullptr, nullptr, nullptr };
+            const char *aCmpsU[3] = { nullptr, nullptr, nullptr };
+            double aScales[3] = { 1., 1., 1. };
+
+            if( MeasureUnit::TWIP == nTargetUnit )
+            {
+                switch( rString[nPos] )
+                {
+                case u'c':
+                case u'C':
+                    aCmpsL[0] = "cm";
+                    aCmpsU[0] = "CM";
+                    aScales[0] = (72.*20.)/2.54; // twip
+                    break;
+                case u'i':
+                case u'I':
+                    aCmpsL[0] = "in";
+                    aCmpsU[0] = "IN";
+                    aScales[0] = 72.*20.; // twip
+                    break;
+                case u'm':
+                case u'M':
+                    aCmpsL[0] = "mm";
+                    aCmpsU[0] = "MM";
+                    aScales[0] = (72.*20.)/25.4; // twip
+                    break;
+                case u'p':
+                case u'P':
+                    aCmpsL[0] = "pt";
+                    aCmpsU[0] = "PT";
+                    aScales[0] = 20.; // twip
+
+                    aCmpsL[1] = "pc";
+                    aCmpsU[1] = "PC";
+                    aScales[1] = 12.*20.; // twip
+                    break;
+                }
+            }
+            else if( MeasureUnit::MM_100TH == nTargetUnit || MeasureUnit::MM_10TH == nTargetUnit )
+            {
+                double nScaleFactor = (MeasureUnit::MM_100TH == nTargetUnit) ? 100.0 : 10.0;
+                switch( rString[nPos] )
+                {
+                case u'c':
+                case u'C':
+                    aCmpsL[0] = "cm";
+                    aCmpsU[0] = "CM";
+                    aScales[0] = 10.0 * nScaleFactor; // mm/100
+                    break;
+                case u'i':
+                case u'I':
+                    aCmpsL[0] = "in";
+                    aCmpsU[0] = "IN";
+                    aScales[0] = 1000.*2.54; // mm/100
+                    break;
+                case u'm':
+                case u'M':
+                    aCmpsL[0] = "mm";
+                    aCmpsU[0] = "MM";
+                    aScales[0] = 1.0 * nScaleFactor; // mm/100
+                    break;
+                case u'p':
+                case u'P':
+                    aCmpsL[0] = "pt";
+                    aCmpsU[0] = "PT";
+                    aScales[0] = (10.0 * nScaleFactor*2.54)/72.; // mm/100
+
+                    aCmpsL[1] = "pc";
+                    aCmpsU[1] = "PC";
+                    aScales[1] = (10.0 * nScaleFactor*2.54)/12.; // mm/100
+
+                    aCmpsL[2] = "px";
+                    aCmpsU[2] = "PX";
+                    aScales[2] = 0.28 * nScaleFactor; // mm/100
+                    break;
+                }
+            }
+            else if( MeasureUnit::POINT == nTargetUnit )
+            {
+                if( rString[nPos] == 'p' || rString[nPos] == 'P' )
+                {
+                    aCmpsL[0] = "pt";
+                    aCmpsU[0] = "PT";
+                    aScales[0] = 1;
+                }
+            }
+
+            if( aCmpsL[0] == nullptr )
+                return false;
+
+            double nScale = 0.;
+            for( sal_uInt16 i= 0; i < 3; i++ )
+            {
+                sal_Int32 nTmp = nPos; // come back to the initial position before each iteration
+                const char *pL = aCmpsL[i];
+                if( pL )
+                {
+                    const char *pU = aCmpsU[i];
+                    while( nTmp < nLen && *pL )
+                    {
+                        sal_Unicode c = rString[nTmp];
+                        if( c != *pL && c != *pU )
+                            break;
+                        pL++;
+                        pU++;
+                        nTmp++;
+                    }
+                    if( !*pL && (nTmp == nLen || ' ' == rString[nTmp]) )
+                    {
+                        nScale = aScales[i];
+                        break;
+                    }
+                }
+            }
+
+            if( 0. == nScale )
+                return false;
+
+            // TODO: check overflow
+            if( nScale != 1. )
+                nVal *= nScale;
+        }
+    }
+
+    nVal += .5;
+    if( bNeg )
+        nVal = -nVal;
+
+    if( nVal <= static_cast<double>(nMin) )
+        rValue = nMin;
+    else if( nVal >= static_cast<double>(nMax) )
+        rValue = nMax;
+    else
+        rValue = static_cast<sal_Int32>(nVal);
+
+    return true;
+}
+
+/** convert measure in given unit to string with given unit */
+void Converter::convertMeasure( OUStringBuffer& rBuffer,
+                                sal_Int32 nMeasure,
+                                sal_Int16 nSourceUnit /* = MeasureUnit::MM_100TH */,
+                                sal_Int16 nTargetUnit /* = MeasureUnit::INCH */  )
+{
+    if( nSourceUnit == MeasureUnit::PERCENT )
+    {
+        OSL_ENSURE( nTargetUnit == MeasureUnit::PERCENT,
+                    "MeasureUnit::PERCENT only maps to MeasureUnit::PERCENT!" );
+
+        rBuffer.append( nMeasure );
+        rBuffer.append( '%' );
+
+        return;
+    }
+    sal_Int64 nValue(nMeasure); // extend to 64-bit first to avoid overflow
+    // the sign is processed separately
+    if (nValue < 0)
+    {
+        nValue = -nValue;
+        rBuffer.append( '-' );
+    }
+
+    // The new length is (nVal * nMul)/(nDiv*nFac*10)
+    long nMul = 1000;
+    long nDiv = 1;
+    long nFac = 100;
+    const char* psUnit = nullptr;
+    switch( nSourceUnit )
+    {
+    case MeasureUnit::TWIP:
+        switch( nTargetUnit )
+        {
+        case MeasureUnit::MM_100TH:
+        case MeasureUnit::MM_10TH:
+            OSL_ENSURE( MeasureUnit::INCH == nTargetUnit,"output unit not supported for twip values" );
+            [[fallthrough]];
+        case MeasureUnit::MM:
+            // 0.01mm = 0.57twip (exactly)
+            nMul = 25400;   // 25.4 * 1000
+            nDiv = 1440;    // 72 * 20;
+            nFac = 100;
+            psUnit = gpsMM;
+            break;
+
+        case MeasureUnit::CM:
+            // 0.001cm = 0.57twip (exactly)
+            nMul = 25400;   // 2.54 * 10000
+            nDiv = 1440;    // 72 * 20;
+            nFac = 1000;
+            psUnit = gpsCM;
+            break;
+
+        case MeasureUnit::POINT:
+            // 0.01pt = 0.2twip (exactly)
+            nMul = 1000;
+            nDiv = 20;
+            nFac = 100;
+            psUnit = gpsPT;
+            break;
+
+        case MeasureUnit::INCH:
+        default:
+            OSL_ENSURE( MeasureUnit::INCH == nTargetUnit,
+                        "output unit not supported for twip values" );
+            // 0.0001in = 0.144twip (exactly)
+            nMul = 100000;
+            nDiv = 1440;    // 72 * 20;
+            nFac = 10000;
+            psUnit = gpsINCH;
+            break;
+        }
+        break;
+
+    case MeasureUnit::POINT:
+        // 1pt = 1pt (exactly)
+        OSL_ENSURE( MeasureUnit::POINT == nTargetUnit,
+                    "output unit not supported for pt values" );
+        nMul = 10;
+        nDiv = 1;
+        nFac = 1;
+        psUnit = gpsPT;
+        break;
+    case MeasureUnit::MM_10TH:
+    case MeasureUnit::MM_100TH:
+        {
+            int nFac2 = (MeasureUnit::MM_100TH == nSourceUnit) ? 100 : 10;
+            switch( nTargetUnit )
+            {
+            case MeasureUnit::MM_100TH:
+            case MeasureUnit::MM_10TH:
+                OSL_ENSURE( MeasureUnit::INCH == nTargetUnit,
+                            "output unit not supported for 1/100mm values" );
+                [[fallthrough]];
+            case MeasureUnit::MM:
+                // 0.01mm = 1 mm/100 (exactly)
+                nMul = 10;
+                nDiv = 1;
+                nFac = nFac2;
+                psUnit = gpsMM;
+                break;
+
+            case MeasureUnit::CM:
+                // 0.001mm = 1 mm/100 (exactly)
+                nMul = 10;
+                nDiv = 1;   // 72 * 20;
+                nFac = 10*nFac2;
+                psUnit = gpsCM;
+                break;
+
+            case MeasureUnit::POINT:
+                // 0.01pt = 0.35 mm/100 (exactly)
+                nMul = 72000;
+                nDiv = 2540;
+                nFac = nFac2;
+                psUnit = gpsPT;
+                break;
+
+            case MeasureUnit::INCH:
+            default:
+                OSL_ENSURE( MeasureUnit::INCH == nTargetUnit,
+                            "output unit not supported for 1/100mm values" );
+                // 0.0001in = 0.254 mm/100 (exactly)
+                nMul = 100000;
+                nDiv = 2540;
+                nFac = 100*nFac2;
+                psUnit = gpsINCH;
+                break;
+            }
+            break;
+        }
+    default:
+        OSL_ENSURE(false, "sax::Converter::convertMeasure(): "
+                "source unit not supported");
+        break;
+    }
+
+    OSL_ENSURE(nValue <= SAL_MAX_INT64 / nMul, "convertMeasure: overflow");
+    nValue *= nMul;
+    nValue /= nDiv;
+    nValue += 5;
+    nValue /= 10;
+
+    rBuffer.append( static_cast<sal_Int64>(nValue / nFac) );
+    if (nFac > 1 && (nValue % nFac) != 0)
+    {
+        rBuffer.append( '.' );
+        while (nFac > 1 && (nValue % nFac) != 0)
+        {
+            nFac /= 10;
+            rBuffer.append( static_cast<sal_Int32>((nValue / nFac) % 10) );
+        }
+    }
+
+    if( psUnit )
+        rBuffer.appendAscii( psUnit );
+}
+
+/** convert string to boolean */
+bool Converter::convertBool( bool& rBool, const OUString& rString )
+{
+    rBool = rString == "true";
+
+    return rBool || (rString == "false");
+}
+
+/** convert boolean to string */
+void Converter::convertBool( OUStringBuffer& rBuffer, bool bValue )
+{
+    rBuffer.append( bValue );
+}
+
+/** convert string to percent */
+bool Converter::convertPercent( sal_Int32& rPercent, const OUString& rString )
+{
+    return convertMeasure( rPercent, rString, MeasureUnit::PERCENT );
+}
+
+/** convert percent to string */
+void Converter::convertPercent( OUStringBuffer& rBuffer, sal_Int32 nValue )
+{
+    rBuffer.append( nValue );
+    rBuffer.append( '%' );
+}
+
+/** convert string to pixel measure */
+bool Converter::convertMeasurePx( sal_Int32& rPixel, const OUString& rString )
+{
+    return convertMeasure( rPixel, rString, MeasureUnit::PIXEL );
+}
+
+/** convert pixel measure to string */
+void Converter::convertMeasurePx( OUStringBuffer& rBuffer, sal_Int32 nValue )
+{
+    rBuffer.append( nValue );
+    rBuffer.append( 'p' );
+    rBuffer.append( 'x' );
+}
+
+static int lcl_gethex( int nChar )
+{
+    if( nChar >= '0' && nChar <= '9' )
+        return nChar - '0';
+    else if( nChar >= 'a' && nChar <= 'f' )
+        return nChar - 'a' + 10;
+    else if( nChar >= 'A' && nChar <= 'F' )
+        return nChar - 'A' + 10;
+    else
+        return 0;
+}
+
+/** convert string to rgb color */
+bool Converter::convertColor( sal_Int32& rColor, const OUString& rValue )
+{
+    if( rValue.getLength() != 7 || rValue[0] != '#' )
+        return false;
+
+    rColor = lcl_gethex( rValue[1] ) * 16 + lcl_gethex( rValue[2] );
+    rColor <<= 8;
+
+    rColor |= ( lcl_gethex( rValue[3] ) * 16 + lcl_gethex( rValue[4] ) );
+    rColor <<= 8;
+
+    rColor |= ( lcl_gethex( rValue[5] ) * 16 + lcl_gethex( rValue[6] ) );
+
+    return true;
+}
+
+static const char aHexTab[] = "0123456789abcdef";
+
+/** convert color to string */
+void Converter::convertColor( OUStringBuffer& rBuffer, sal_Int32 nColor )
+{
+    rBuffer.append( '#' );
+
+    sal_uInt8 nCol = static_cast<sal_uInt8>(nColor >> 16);
+    rBuffer.append( sal_Unicode( aHexTab[ nCol >> 4 ] ) );
+    rBuffer.append( sal_Unicode( aHexTab[ nCol & 0xf ] ) );
+
+    nCol = static_cast<sal_uInt8>(nColor >> 8);
+    rBuffer.append( sal_Unicode( aHexTab[ nCol >> 4 ] ) );
+    rBuffer.append( sal_Unicode( aHexTab[ nCol & 0xf ] ) );
+
+    nCol = static_cast<sal_uInt8>(nColor);
+    rBuffer.append( sal_Unicode( aHexTab[ nCol >> 4 ] ) );
+    rBuffer.append( sal_Unicode( aHexTab[ nCol & 0xf ] ) );
+}
+
+/** convert string to number with optional min and max values */
+bool Converter::convertNumber(  sal_Int32& rValue,
+                                std::u16string_view aString,
+                                sal_Int32 nMin, sal_Int32 nMax )
+{
+    rValue = 0;
+    sal_Int64 nNumber = 0;
+    bool bRet = convertNumber64(nNumber,aString,nMin,nMax);
+    if ( bRet )
+        rValue = static_cast<sal_Int32>(nNumber);
+    return bRet;
+}
+
+/** convert string to 64-bit number with optional min and max values */
+bool Converter::convertNumber64( sal_Int64& rValue,
+                                 std::u16string_view aString,
+                                 sal_Int64 nMin, sal_Int64 nMax )
+{
+    sal_Int32 nPos = 0;
+    sal_Int32 const nLen = aString.size();
+
+    // skip white space
+    while( (nPos < nLen) && (aString[nPos] <= ' ') )
+        nPos++;
+
+    sal_Int32 nNumberStartPos = nPos;
+
+    if( nPos < nLen && '-' == aString[nPos] )
+    {
+        nPos++;
+    }
+
+    // get number
+    while( nPos < nLen &&
+           '0' <= aString[nPos] &&
+           '9' >= aString[nPos] )
+    {
+        nPos++;
+    }
+
+    rValue = rtl_ustr_toInt64_WithLength(aString.data() + nNumberStartPos, 10, nPos - nNumberStartPos);
+
+    if( rValue < nMin )
+        rValue = nMin;
+    else if( rValue > nMax )
+        rValue = nMax;
+
+    return ( nPos == nLen && rValue >= nMin && rValue <= nMax );
+}
+
+/** convert double number to string (using ::rtl::math) */
+void Converter::convertDouble(  OUStringBuffer& rBuffer,
+                                double fNumber,
+                                bool bWriteUnits,
+                                sal_Int16 nSourceUnit,
+                                sal_Int16 nTargetUnit)
+{
+    if(MeasureUnit::PERCENT == nSourceUnit)
+    {
+        OSL_ENSURE( nTargetUnit == MeasureUnit::PERCENT, "MeasureUnit::PERCENT only maps to MeasureUnit::PERCENT!" );
+        ::rtl::math::doubleToUStringBuffer( rBuffer, fNumber, rtl_math_StringFormat_Automatic, rtl_math_DecimalPlaces_Max, '.', true);
+        if(bWriteUnits)
+            rBuffer.append('%');
+    }
+    else
+    {
+        OUStringBuffer sUnit;
+        double fFactor = GetConversionFactor(sUnit, nSourceUnit, nTargetUnit);
+        if(fFactor != 1.0)
+            fNumber *= fFactor;
+        ::rtl::math::doubleToUStringBuffer( rBuffer, fNumber, rtl_math_StringFormat_Automatic, rtl_math_DecimalPlaces_Max, '.', true);
+        if(bWriteUnits)
+            rBuffer.append(sUnit.makeStringAndClear());
+    }
+}
+
+/** convert double number to string (using ::rtl::math) */
+void Converter::convertDouble( OUStringBuffer& rBuffer, double fNumber)
+{
+    ::rtl::math::doubleToUStringBuffer( rBuffer, fNumber, rtl_math_StringFormat_Automatic, rtl_math_DecimalPlaces_Max, '.', true);
+}
+
+/** convert string to double number (using ::rtl::math) */
+bool Converter::convertDouble(double& rValue,
+    const OUString& rString, sal_Int16 nSourceUnit, sal_Int16 nTargetUnit)
+{
+    rtl_math_ConversionStatus eStatus;
+    rValue = ::rtl::math::stringToDouble( rString, '.', ',', &eStatus );
+
+    if(eStatus == rtl_math_ConversionStatus_Ok)
+    {
+        OUStringBuffer sUnit;
+        // fdo#48969: switch source and target because factor is used to divide!
+        double const fFactor =
+            GetConversionFactor(sUnit, nTargetUnit, nSourceUnit);
+        if(fFactor != 1.0 && fFactor != 0.0)
+            rValue /= fFactor;
+    }
+
+    return ( eStatus == rtl_math_ConversionStatus_Ok );
+}
+
+/** convert string to double number (using ::rtl::math) */
+bool Converter::convertDouble(double& rValue, const OUString& rString)
+{
+    rtl_math_ConversionStatus eStatus;
+    rValue = ::rtl::math::stringToDouble( rString, '.', ',', &eStatus );
+    return ( eStatus == rtl_math_ConversionStatus_Ok );
+}
+
+/** convert number, 10th of degrees with range [0..3600] to SVG angle */
+void Converter::convertAngle(OUStringBuffer& rBuffer, sal_Int16 const nAngle,
+        SvtSaveOptions::ODFSaneDefaultVersion const nVersion)
+{
+    if (nVersion < SvtSaveOptions::ODFSVER_012 || nVersion == SvtSaveOptions::ODFSVER_012_EXT_COMPAT)
+    {
+        // wrong, but backward compatible with OOo/LO < 4.4
+        rBuffer.append(static_cast<sal_Int32>(nAngle));
+    }
+    else
+    { // OFFICE-3774 tdf#89475 write valid ODF 1.2 angle; needs LO 4.4 to import
+        double fAngle(double(nAngle) / 10.0);
+        ::sax::Converter::convertDouble(rBuffer, fAngle);
+        rBuffer.append("deg");
+    }
+}
+
+/** convert SVG angle to number, 10th of degrees with range [0..3600] */
+bool Converter::convertAngle(sal_Int16& rAngle, OUString const& rString,
+        bool const isWrongOOo10thDegAngle)
+{
+    // ODF 1.1 leaves it undefined what the number means, but ODF 1.2 says it's
+    // degrees, while OOo has historically used 10th of degrees :(
+    // So import degrees when we see the "deg" suffix but continue with 10th of
+    // degrees for now for the sake of existing OOo/LO documents, until the
+    // new versions that can read "deg" suffix are widely deployed and we can
+    // start to write the "deg" suffix.
+    sal_Int32 nValue(0);
+    double fValue(0.0);
+    bool bRet = ::sax::Converter::convertDouble(fValue, rString);
+    if (-1 != rString.indexOf("deg"))
+    {
+        nValue = fValue * 10.0;
+    }
+    else if (-1 != rString.indexOf("grad"))
+    {
+        nValue = (fValue * 9.0 / 10.0) * 10.0;
+    }
+    else if (-1 != rString.indexOf("rad"))
+    {
+        nValue = basegfx::rad2deg(fValue) * 10.0;
+    }
+    else // no explicit unit
+    {
+        if (isWrongOOo10thDegAngle)
+        {
+            nValue = fValue; // wrong, but backward compatible with OOo/LO < 7.0
+        }
+        else
+        {
+            nValue = fValue * 10.0; // ODF 1.2
+        }
+    }
+    // limit to valid range [0..3600]
+    nValue = nValue % 3600;
+    if (nValue < 0)
+    {
+        nValue += 3600;
+    }
+    assert(0 <= nValue && nValue <= 3600);
+    if (bRet)
+    {
+        rAngle = sal::static_int_cast<sal_Int16>(nValue);
+    }
+    return bRet;
+}
+
+/** convert double to ISO "duration" string; negative durations allowed */
+void Converter::convertDuration(OUStringBuffer& rBuffer,
+                                const double fTime)
+{
+    double fValue = fTime;
+
+    // take care of negative durations as specified in:
+    // XML Schema, W3C Working Draft 07 April 2000, section 3.2.6.1
+    if (fValue < 0.0)
+    {
+        rBuffer.append('-');
+        fValue = - fValue;
+    }
+
+    rBuffer.append( "PT" );
+    fValue *= 24;
+    double fHoursValue = ::rtl::math::approxFloor (fValue);
+    fValue -= fHoursValue;
+    fValue *= 60;
+    double fMinsValue = ::rtl::math::approxFloor (fValue);
+    fValue -= fMinsValue;
+    fValue *= 60;
+    double fSecsValue = ::rtl::math::approxFloor (fValue);
+    fValue -= fSecsValue;
+    double fNanoSecsValue;
+    if (fValue > 0.00000000001)
+        fNanoSecsValue = ::rtl::math::round( fValue, XML_MAXDIGITSCOUNT_TIME - 5);
+    else
+        fNanoSecsValue = 0.0;
+
+    if (fNanoSecsValue == 1.0)
+    {
+        fNanoSecsValue = 0.0;
+        fSecsValue += 1.0;
+    }
+    if (fSecsValue >= 60.0)
+    {
+        fSecsValue -= 60.0;
+        fMinsValue += 1.0;
+    }
+    if (fMinsValue >= 60.0)
+    {
+        fMinsValue -= 60.0;
+        fHoursValue += 1.0;
+    }
+
+    if (fHoursValue < 10)
+        rBuffer.append( '0');
+    rBuffer.append( sal_Int32( fHoursValue));
+    rBuffer.append( 'H');
+    if (fMinsValue < 10)
+        rBuffer.append( '0');
+    rBuffer.append( sal_Int32( fMinsValue));
+    rBuffer.append( 'M');
+    if (fSecsValue < 10)
+        rBuffer.append( '0');
+    rBuffer.append( sal_Int32( fSecsValue));
+    if (fNanoSecsValue > 0.0)
+    {
+        OUString aNS( ::rtl::math::doubleToUString( fValue,
+                    rtl_math_StringFormat_F, XML_MAXDIGITSCOUNT_TIME - 5, '.',
+                    true));
+        if ( aNS.getLength() > 2 )
+        {
+            rBuffer.append( '.');
+            rBuffer.append( std::u16string_view(aNS).substr(2) );     // strip "0."
+        }
+    }
+    rBuffer.append( 'S');
+}
+
+/** convert ISO "duration" string to double; negative durations allowed */
+bool Converter::convertDuration(double& rfTime,
+                                const OUString& rString)
+{
+    OUString aTrimmed = rString.trim().toAsciiUpperCase();
+    const sal_Unicode* pStr = aTrimmed.getStr();
+
+    // negative time duration?
+    bool bIsNegativeDuration = false;
+    if ( '-' == (*pStr) )
+    {
+        bIsNegativeDuration = true;
+        pStr++;
+    }
+
+    if ( *(pStr++) != 'P' )            // duration must start with "P"
+        return false;
+
+    OUStringBuffer sDoubleStr;
+    bool bSuccess = true;
+    bool bDone = false;
+    bool bTimePart = false;
+    bool bIsFraction = false;
+    sal_Int32 nDays  = 0;
+    sal_Int32 nHours = 0;
+    sal_Int32 nMins  = 0;
+    sal_Int32 nSecs  = 0;
+    sal_Int32 nTemp = 0;
+
+    while ( bSuccess && !bDone )
+    {
+        sal_Unicode c = *(pStr++);
+        if ( !c )                               // end
+            bDone = true;
+        else if ( '0' <= c && '9' >= c )
+        {
+            if ( nTemp >= SAL_MAX_INT32 / 10 )
+                bSuccess = false;
+            else
+            {
+                if ( !bIsFraction )
+                {
+                    nTemp *= 10;
+                    nTemp += (c - u'0');
+                }
+                else
+                {
+                    sDoubleStr.append(c);
+                }
+            }
+        }
+        else if ( bTimePart )
+        {
+            if ( c == 'H' )
+            {
+                nHours = nTemp;
+                nTemp = 0;
+            }
+            else if ( c == 'M' )
+            {
+                nMins = nTemp;
+                nTemp = 0;
+            }
+            else if ( (c == ',') || (c == '.') )
+            {
+                nSecs = nTemp;
+                nTemp = 0;
+                bIsFraction = true;
+                sDoubleStr = "0.";
+            }
+            else if ( c == 'S' )
+            {
+                if ( !bIsFraction )
+                {
+                    nSecs = nTemp;
+                    nTemp = 0;
+                    sDoubleStr = "0.0";
+                }
+            }
+            else
+                bSuccess = false;               // invalid character
+        }
+        else
+        {
+            if ( c == 'T' )            // "T" starts time part
+                bTimePart = true;
+            else if ( c == 'D' )
+            {
+                nDays = nTemp;
+                nTemp = 0;
+            }
+            else if ( c == 'Y' || c == 'M' )
+            {
+                //! how many days is a year or month?
+
+                OSL_FAIL( "years or months in duration: not implemented");
+                bSuccess = false;
+            }
+            else
+                bSuccess = false;               // invalid character
+        }
+    }
+
+    if ( bSuccess )
+    {
+        if ( nDays )
+            nHours += nDays * 24;               // add the days to the hours part
+        double fHour = nHours;
+        double fMin = nMins;
+        double fSec = nSecs;
+        double fFraction = sDoubleStr.makeStringAndClear().toDouble();
+        double fTempTime = fHour / 24;
+        fTempTime += fMin / (24 * 60);
+        fTempTime += fSec / (24 * 60 * 60);
+        fTempTime += fFraction / (24 * 60 * 60);
+
+        // negative duration?
+        if ( bIsNegativeDuration )
+        {
+            fTempTime = -fTempTime;
+        }
+
+        rfTime = fTempTime;
+    }
+    return bSuccess;
+}
+
+/** convert util::Duration to ISO8601 "duration" string */
+void Converter::convertDuration(OUStringBuffer& rBuffer,
+        const ::util::Duration& rDuration)
+{
+    if (rDuration.Negative)
+    {
+        rBuffer.append('-');
+    }
+    rBuffer.append('P');
+    const bool bHaveDate(rDuration.Years  != 0 ||
+                         rDuration.Months != 0 ||
+                         rDuration.Days   != 0);
+    if (rDuration.Years)
+    {
+        rBuffer.append(static_cast<sal_Int32>(rDuration.Years));
+        rBuffer.append('Y');
+    }
+    if (rDuration.Months)
+    {
+        rBuffer.append(static_cast<sal_Int32>(rDuration.Months));
+        rBuffer.append('M');
+    }
+    if (rDuration.Days)
+    {
+        rBuffer.append(static_cast<sal_Int32>(rDuration.Days));
+        rBuffer.append('D');
+    }
+    if ( rDuration.Hours != 0
+         || rDuration.Minutes != 0
+         || rDuration.Seconds != 0
+         || rDuration.NanoSeconds != 0 )
+    {
+        rBuffer.append('T'); // time separator
+        if (rDuration.Hours)
+        {
+            rBuffer.append(static_cast<sal_Int32>(rDuration.Hours));
+            rBuffer.append('H');
+        }
+        if (rDuration.Minutes)
+        {
+            rBuffer.append(static_cast<sal_Int32>(rDuration.Minutes));
+            rBuffer.append('M');
+        }
+        if (rDuration.Seconds != 0 || rDuration.NanoSeconds != 0)
+        {
+            // seconds must not be omitted (i.e. ".42S" is not valid)
+            rBuffer.append(static_cast<sal_Int32>(rDuration.Seconds));
+            if (rDuration.NanoSeconds)
+            {
+                OSL_ENSURE(rDuration.NanoSeconds < 1000000000,"NanoSeconds cannot be more than 999 999 999");
+                rBuffer.append('.');
+                std::ostringstream ostr;
+                ostr.fill('0');
+                ostr.width(9);
+                ostr << rDuration.NanoSeconds;
+                rBuffer.append(OUString::createFromAscii(ostr.str().c_str()));
+            }
+            rBuffer.append('S');
+        }
+    }
+    else if (!bHaveDate)
+    {
+        // zero duration: XMLSchema-2 says there must be at least one component
+        rBuffer.append('0');
+        rBuffer.append('D');
+    }
+}
+
+namespace {
+
+enum Result { R_NOTHING, R_OVERFLOW, R_SUCCESS };
+
+}
+
+static Result
+readUnsignedNumber(const OUString & rString,
+    sal_Int32 & io_rnPos, sal_Int32 & o_rNumber)
+{
+    sal_Int32 nPos(io_rnPos);
+
+    while (nPos < rString.getLength())
+    {
+        const sal_Unicode c = rString[nPos];
+        if (!(('0' <= c) && (c <= '9')))
+            break;
+        ++nPos;
+    }
+
+    if (io_rnPos == nPos) // read something?
+    {
+        o_rNumber = -1;
+        return R_NOTHING;
+    }
+
+    const sal_Int64 nTemp = rtl_ustr_toInt64_WithLength(rString.getStr() + io_rnPos, 10, nPos - io_rnPos);
+
+    const bool bOverflow = (nTemp >= SAL_MAX_INT32);
+
+    io_rnPos = nPos;
+    o_rNumber = nTemp;
+    return bOverflow ? R_OVERFLOW : R_SUCCESS;
+}
+
+static Result
+readUnsignedNumberMaxDigits(int maxDigits,
+                            const OUString & rString, sal_Int32 & io_rnPos,
+                            sal_Int32 & o_rNumber)
+{
+    bool bOverflow(false);
+    sal_Int64 nTemp(0);
+    sal_Int32 nPos(io_rnPos);
+    OSL_ENSURE(maxDigits >= 0, "negative amount of digits makes no sense");
+
+    while (nPos < rString.getLength())
+    {
+        const sal_Unicode c = rString[nPos];
+        if (('0' <= c) && (c <= '9'))
+        {
+            if (maxDigits > 0)
+            {
+                nTemp *= 10;
+                nTemp += (c - u'0');
+                if (nTemp >= SAL_MAX_INT32)
+                {
+                    bOverflow = true;
+                }
+                --maxDigits;
+            }
+        }
+        else
+        {
+            break;
+        }
+        ++nPos;
+    }
+
+    if (io_rnPos == nPos) // read something?
+    {
+        o_rNumber = -1;
+        return R_NOTHING;
+    }
+
+    io_rnPos = nPos;
+    o_rNumber = nTemp;
+    return bOverflow ? R_OVERFLOW : R_SUCCESS;
+}
+
+static bool
+readDurationT(const OUString & rString, sal_Int32 & io_rnPos)
+{
+    if ((io_rnPos < rString.getLength()) &&
+        (rString[io_rnPos] == 'T'))
+    {
+        ++io_rnPos;
+        return true;
+    }
+    return false;
+}
+
+static bool
+readDurationComponent(const OUString & rString,
+    sal_Int32 & io_rnPos, sal_Int32 & io_rnTemp, bool & io_rbTimePart,
+    sal_Int32 & o_rnTarget, const sal_Unicode c)
+{
+    if (io_rnPos < rString.getLength())
+    {
+        if (c == rString[io_rnPos])
+        {
+            ++io_rnPos;
+            if (-1 != io_rnTemp)
+            {
+                o_rnTarget = io_rnTemp;
+                io_rnTemp = -1;
+                if (!io_rbTimePart)
+                {
+                    io_rbTimePart = readDurationT(rString, io_rnPos);
+                }
+                return (R_OVERFLOW !=
+                        readUnsignedNumber(rString, io_rnPos, io_rnTemp));
+            }
+            else
+            {
+                return false;
+            }
+        }
+    }
+    return true;
+}
+
+/** convert ISO8601 "duration" string to util::Duration */
+bool Converter::convertDuration(util::Duration& rDuration,
+                                const OUString& rString)
+{
+    const OUString string = rString.trim().toAsciiUpperCase();
+    sal_Int32 nPos(0);
+
+    bool bIsNegativeDuration(false);
+    if (!string.isEmpty() && ('-' == string[0]))
+    {
+        bIsNegativeDuration = true;
+        ++nPos;
+    }
+
+    if ((nPos < string.getLength())
+        && (string[nPos] != 'P')) // duration must start with "P"
+    {
+        return false;
+    }
+
+    ++nPos;
+
+    /// last read number; -1 == no valid number! always reset after using!
+    sal_Int32 nTemp(-1);
+    bool bTimePart(false); // have we read 'T'?
+    bool bSuccess(false);
+    sal_Int32 nYears(0);
+    sal_Int32 nMonths(0);
+    sal_Int32 nDays(0);
+    sal_Int32 nHours(0);
+    sal_Int32 nMinutes(0);
+    sal_Int32 nSeconds(0);
+    sal_Int32 nNanoSeconds(0);
+
+    bTimePart = readDurationT(string, nPos);
+    bSuccess = (R_SUCCESS == readUnsignedNumber(string, nPos, nTemp));
+
+    if (!bTimePart && bSuccess)
+    {
+        bSuccess = readDurationComponent(string, nPos, nTemp, bTimePart,
+                     nYears, 'Y');
+    }
+
+    if (!bTimePart && bSuccess)
+    {
+        bSuccess = readDurationComponent(string, nPos, nTemp, bTimePart,
+                     nMonths, 'M');
+    }
+
+    if (!bTimePart && bSuccess)
+    {
+        bSuccess = readDurationComponent(string, nPos, nTemp, bTimePart,
+                     nDays, 'D');
+    }
+
+    if (bTimePart)
+    {
+        if (-1 == nTemp) // a 'T' must be followed by a component
+        {
+            bSuccess = false;
+        }
+
+        if (bSuccess)
+        {
+            bSuccess = readDurationComponent(string, nPos, nTemp, bTimePart,
+                         nHours, 'H');
+        }
+
+        if (bSuccess)
+        {
+            bSuccess = readDurationComponent(string, nPos, nTemp, bTimePart,
+                         nMinutes, 'M');
+        }
+
+        // eeek! seconds are icky.
+        if ((nPos < string.getLength()) && bSuccess)
+        {
+            if (string[nPos] == '.' ||
+                string[nPos] == ',')
+            {
+                ++nPos;
+                if (-1 != nTemp)
+                {
+                    nSeconds = nTemp;
+                    nTemp = -1;
+                    const sal_Int32 nStart(nPos);
+                    bSuccess = readUnsignedNumberMaxDigits(9, string, nPos, nTemp) == R_SUCCESS;
+                    if ((nPos < string.getLength()) && bSuccess)
+                    {
+                        if (-1 != nTemp)
+                        {
+                            nNanoSeconds = nTemp;
+                            sal_Int32 nDigits = nPos - nStart;
+                            assert(nDigits >= 0);
+                            for (; nDigits < 9; ++nDigits)
+                            {
+                                nNanoSeconds *= 10;
+                            }
+                            nTemp=-1;
+                            if ('S' == string[nPos])
+                            {
+                                ++nPos;
+                            }
+                            else
+                            {
+                                bSuccess = false;
+                            }
+                        }
+                        else
+                        {
+                            bSuccess = false;
+                        }
+                    }
+                }
+                else
+                {
+                    bSuccess = false;
+                }
+            }
+            else if ('S' == string[nPos])
+            {
+                ++nPos;
+                if (-1 != nTemp)
+                {
+                    nSeconds = nTemp;
+                    nTemp = -1;
+                }
+                else
+                {
+                    bSuccess = false;
+                }
+            }
+        }
+    }
+
+    if (nPos != string.getLength()) // string not processed completely?
+    {
+        bSuccess = false;
+    }
+
+    if (nTemp != -1) // unprocessed number?
+    {
+        bSuccess = false;
+    }
+
+    if (bSuccess)
+    {
+        rDuration.Negative      = bIsNegativeDuration;
+        rDuration.Years         = static_cast<sal_Int16>(nYears);
+        rDuration.Months        = static_cast<sal_Int16>(nMonths);
+        rDuration.Days          = static_cast<sal_Int16>(nDays);
+        rDuration.Hours         = static_cast<sal_Int16>(nHours);
+        rDuration.Minutes       = static_cast<sal_Int16>(nMinutes);
+        rDuration.Seconds       = static_cast<sal_Int16>(nSeconds);
+        rDuration.NanoSeconds   = nNanoSeconds;
+    }
+
+    return bSuccess;
+}
+
+
+static void
+lcl_AppendTimezone(OUStringBuffer & i_rBuffer, int const nOffset)
+{
+    if (0 == nOffset)
+    {
+        i_rBuffer.append('Z');
+    }
+    else
+    {
+        if (0 < nOffset)
+        {
+            i_rBuffer.append('+');
+        }
+        else
+        {
+            i_rBuffer.append('-');
+        }
+        const sal_Int32 nHours  (abs(nOffset) / 60);
+        const sal_Int32 nMinutes(abs(nOffset) % 60);
+        SAL_WARN_IF(nHours > 14 || (nHours == 14 && nMinutes > 0),
+                "sax", "convertDateTime: timezone overflow");
+        if (nHours < 10)
+        {
+            i_rBuffer.append('0');
+        }
+        i_rBuffer.append(nHours);
+        i_rBuffer.append(':');
+        if (nMinutes < 10)
+        {
+            i_rBuffer.append('0');
+        }
+        i_rBuffer.append(nMinutes);
+    }
+}
+
+/** convert util::Date to ISO "date" string */
+void Converter::convertDate(
+        OUStringBuffer& i_rBuffer,
+        const util::Date& i_rDate,
+        sal_Int16 const*const pTimeZoneOffset)
+{
+    const util::DateTime dt(0, 0, 0, 0,
+        i_rDate.Day, i_rDate.Month, i_rDate.Year, false);
+    convertDateTime(i_rBuffer, dt, pTimeZoneOffset);
+}
+
+static void convertTime(
+        OUStringBuffer& i_rBuffer,
+        const css::util::DateTime& i_rDateTime)
+{
+    if (i_rDateTime.Hours   < 10) {
+        i_rBuffer.append('0');
+    }
+    i_rBuffer.append( static_cast<sal_Int32>(i_rDateTime.Hours)   )
+             .append(':');
+    if (i_rDateTime.Minutes < 10) {
+        i_rBuffer.append('0');
+    }
+    i_rBuffer.append( static_cast<sal_Int32>(i_rDateTime.Minutes) )
+             .append(':');
+    if (i_rDateTime.Seconds < 10) {
+        i_rBuffer.append('0');
+    }
+    i_rBuffer.append( static_cast<sal_Int32>(i_rDateTime.Seconds) );
+    if (i_rDateTime.NanoSeconds > 0) {
+        OSL_ENSURE(i_rDateTime.NanoSeconds < 1000000000,"NanoSeconds cannot be more than 999 999 999");
+        i_rBuffer.append('.');
+        std::ostringstream ostr;
+        ostr.fill('0');
+        ostr.width(9);
+        ostr << i_rDateTime.NanoSeconds;
+        i_rBuffer.append(OUString::createFromAscii(ostr.str().c_str()));
+    }
+}
+
+static void convertTimeZone(
+        OUStringBuffer& i_rBuffer,
+        const css::util::DateTime& i_rDateTime,
+        sal_Int16 const* pTimeZoneOffset)
+{
+    if (pTimeZoneOffset)
+    {
+        lcl_AppendTimezone(i_rBuffer, *pTimeZoneOffset);
+    }
+    else if (i_rDateTime.IsUTC)
+    {
+        lcl_AppendTimezone(i_rBuffer, 0);
+    }
+}
+
+/** convert util::DateTime to ISO "time" or "dateTime" string */
+void Converter::convertTimeOrDateTime(
+        OUStringBuffer& i_rBuffer,
+        const css::util::DateTime& i_rDateTime)
+{
+    if (i_rDateTime.Year == 0 ||
+        i_rDateTime.Month < 1 || i_rDateTime.Month > 12 ||
+        i_rDateTime.Day < 1 || i_rDateTime.Day > 31)
+    {
+        convertTime(i_rBuffer, i_rDateTime);
+        convertTimeZone(i_rBuffer, i_rDateTime, nullptr);
+    }
+    else
+    {
+        convertDateTime(i_rBuffer, i_rDateTime, nullptr, true);
+    }
+}
+
+/** convert util::DateTime to ISO "date" or "dateTime" string */
+void Converter::convertDateTime(
+        OUStringBuffer& i_rBuffer,
+        const css::util::DateTime& i_rDateTime,
+        sal_Int16 const*const pTimeZoneOffset,
+        bool i_bAddTimeIf0AM )
+{
+    const sal_Unicode dash('-');
+    const sal_Unicode zero('0');
+
+    sal_Int32 const nYear(abs(i_rDateTime.Year));
+    if (i_rDateTime.Year < 0) {
+        i_rBuffer.append(dash); // negative
+    }
+    if (nYear < 1000) {
+        i_rBuffer.append(zero);
+    }
+    if (nYear < 100) {
+        i_rBuffer.append(zero);
+    }
+    if (nYear < 10) {
+        i_rBuffer.append(zero);
+    }
+    i_rBuffer.append(nYear).append(dash);
+    if( i_rDateTime.Month < 10 ) {
+        i_rBuffer.append(zero);
+    }
+    i_rBuffer.append( static_cast<sal_Int32>(i_rDateTime.Month) ).append(dash);
+    if( i_rDateTime.Day   < 10 ) {
+        i_rBuffer.append(zero);
+    }
+    i_rBuffer.append( static_cast<sal_Int32>(i_rDateTime.Day)   );
+
+    if( i_rDateTime.Seconds != 0 ||
+        i_rDateTime.Minutes != 0 ||
+        i_rDateTime.Hours   != 0 ||
+        i_bAddTimeIf0AM )
+    {
+        i_rBuffer.append('T');
+        convertTime(i_rBuffer, i_rDateTime);
+    }
+
+    convertTimeZone(i_rBuffer, i_rDateTime, pTimeZoneOffset);
+}
+
+/** convert ISO "date" or "dateTime" string to util::DateTime */
+bool Converter::parseDateTime(   util::DateTime& rDateTime,
+                                 const OUString& rString )
+{
+    bool isDateTime;
+    return parseDateOrDateTime(nullptr, rDateTime, isDateTime, nullptr,
+            rString);
+}
+
+static bool lcl_isLeapYear(const sal_uInt32 nYear)
+{
+    return ((nYear % 4) == 0)
+        && (((nYear % 100) != 0) || ((nYear % 400) == 0));
+}
+
+static sal_uInt16
+lcl_MaxDaysPerMonth(const sal_Int32 nMonth, const sal_Int32 nYear)
+{
+    static const sal_uInt16 s_MaxDaysPerMonth[12] =
+        { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 };
+    assert(0 < nMonth && nMonth <= 12);
+    if ((2 == nMonth) && lcl_isLeapYear(nYear))
+    {
+        return 29;
+    }
+    return s_MaxDaysPerMonth[nMonth - 1];
+}
+
+static void lcl_ConvertToUTC(
+        sal_Int16 & o_rYear, sal_uInt16 & o_rMonth, sal_uInt16 & o_rDay,
+        sal_uInt16 & o_rHours, sal_uInt16 & o_rMinutes,
+        int const nSourceOffset)
+{
+    sal_Int16 nOffsetHours(abs(nSourceOffset) / 60);
+    sal_Int16 const nOffsetMinutes(abs(nSourceOffset) % 60);
+    o_rMinutes += nOffsetMinutes;
+    if (nSourceOffset < 0)
+    {
+        o_rMinutes += nOffsetMinutes;
+        if (60 <= o_rMinutes)
+        {
+            o_rMinutes -= 60;
+            ++nOffsetHours;
+        }
+        o_rHours += nOffsetHours;
+        if (o_rHours < 24)
+        {
+            return;
+        }
+        sal_Int16 nDayAdd(0);
+        while (24 <= o_rHours)
+        {
+            o_rHours -= 24;
+            ++nDayAdd;
+        }
+        if (o_rDay == 0)
+        {
+            return; // handle time without date - don't adjust what isn't there
+        }
+        o_rDay += nDayAdd;
+        sal_Int16 const nDaysInMonth(lcl_MaxDaysPerMonth(o_rMonth, o_rYear));
+        if (o_rDay <= nDaysInMonth)
+        {
+            return;
+        }
+        o_rDay -= nDaysInMonth;
+        ++o_rMonth;
+        if (o_rMonth <= 12)
+        {
+            return;
+        }
+        o_rMonth = 1;
+        ++o_rYear; // works for negative year too
+    }
+    else if (0 < nSourceOffset)
+    {
+        // argh everything is unsigned
+        if (o_rMinutes < nOffsetMinutes)
+        {
+            o_rMinutes += 60;
+            ++nOffsetHours;
+        }
+        o_rMinutes -= nOffsetMinutes;
+        sal_Int16 nDaySubtract(0);
+        while (o_rHours < nOffsetHours)
+        {
+            o_rHours += 24;
+            ++nDaySubtract;
+        }
+        o_rHours -= nOffsetHours;
+        if (o_rDay == 0)
+        {
+            return; // handle time without date - don't adjust what isn't there
+        }
+        if (nDaySubtract < o_rDay)
+        {
+            o_rDay -= nDaySubtract;
+            return;
+        }
+        sal_Int16 const nPrevMonth((o_rMonth == 1) ? 12 : o_rMonth - 1);
+        sal_Int16 const nDaysInMonth(lcl_MaxDaysPerMonth(nPrevMonth, o_rYear));
+        o_rDay += nDaysInMonth;
+        --o_rMonth;
+        if (0 == o_rMonth)
+        {
+            o_rMonth = 12;
+            --o_rYear; // works for negative year too
+        }
+        o_rDay -= nDaySubtract;
+    }
+}
+
+static bool
+readDateTimeComponent(const OUString & rString,
+    sal_Int32 & io_rnPos, sal_Int32 & o_rnTarget,
+    const sal_Int32 nMinLength, const bool bExactLength)
+{
+    const sal_Int32 nOldPos(io_rnPos);
+    sal_Int32 nTemp(0);
+    if (R_SUCCESS != readUnsignedNumber(rString, io_rnPos, nTemp))
+    {
+        return false;
+    }
+    const sal_Int32 nTokenLength(io_rnPos - nOldPos);
+    if ((nTokenLength < nMinLength) ||
+        (bExactLength && (nTokenLength > nMinLength)))
+    {
+        return false; // bad length
+    }
+    o_rnTarget = nTemp;
+    return true;
+}
+
+/** convert ISO "date" or "dateTime" string to util::DateTime or util::Date */
+static bool lcl_parseDate(
+                bool & isNegative,
+                sal_Int32 & nYear, sal_Int32 & nMonth, sal_Int32 & nDay,
+                bool & bHaveTime,
+                sal_Int32 & nPos,
+                const OUString & string,
+                bool const bIgnoreInvalidOrMissingDate)
+{
+    bool bSuccess = true;
+
+    if (string.getLength() > nPos)
+    {
+        if ('-' == string[nPos])
+        {
+            isNegative = true;
+            ++nPos;
+        }
+    }
+
+    {
+        // While W3C XMLSchema specifies years with a minimum of 4 digits, be
+        // lenient in what we accept for years < 1000. One digit is acceptable
+        // if the remainders match.
+        bSuccess = readDateTimeComponent(string, nPos, nYear, 1, false);
+        if (!bIgnoreInvalidOrMissingDate)
+        {
+            bSuccess &= (0 < nYear);
+        }
+        bSuccess &= (nPos < string.getLength()); // not last token
+    }
+    if (bSuccess && ('-' != string[nPos])) // separator
+    {
+        bSuccess = false;
+    }
+    if (bSuccess)
+    {
+        ++nPos;
+
+        bSuccess = readDateTimeComponent(string, nPos, nMonth, 2, true);
+        if (!bIgnoreInvalidOrMissingDate)
+        {
+            bSuccess &= (0 < nMonth);
+        }
+        bSuccess &= (nMonth <= 12);
+        bSuccess &= (nPos < string.getLength()); // not last token
+    }
+    if (bSuccess && ('-' != string[nPos])) // separator
+    {
+        bSuccess = false;
+    }
+    if (bSuccess)
+    {
+        ++nPos;
+
+        bSuccess = readDateTimeComponent(string, nPos, nDay, 2, true);
+        if (!bIgnoreInvalidOrMissingDate)
+        {
+            bSuccess &= (0 < nDay);
+        }
+        if (nMonth > 0) // not possible to check if month was missing
+        {
+            bSuccess &= (nDay <= lcl_MaxDaysPerMonth(nMonth, nYear));
+        }
+        else assert(bIgnoreInvalidOrMissingDate);
+    }
+
+    if (bSuccess && (nPos < string.getLength()))
+    {
+        if ('T' == string[nPos]) // time separator
+        {
+            bHaveTime = true;
+            ++nPos;
+        }
+    }
+
+    return bSuccess;
+}
+
+/** convert ISO "date" or "dateTime" string to util::DateTime or util::Date */
+static bool lcl_parseDateTime(
+                util::Date *const pDate, util::DateTime & rDateTime,
+                bool & rbDateTime,
+                std::optional<sal_Int16> *const pTimeZoneOffset,
+                const OUString & rString,
+                bool const bIgnoreInvalidOrMissingDate)
+{
+    bool bSuccess = true;
+
+    const OUString string = rString.trim().toAsciiUpperCase();
+
+    bool isNegative(false);
+    sal_Int32 nYear(0);
+    sal_Int32 nMonth(0);
+    sal_Int32 nDay(0);
+    sal_Int32 nPos(0);
+    bool bHaveTime(false);
+
+    if (    !bIgnoreInvalidOrMissingDate
+        ||  string.indexOf(':') == -1  // no time?
+        ||  (string.indexOf('-') != -1
+             && string.indexOf('-') < string.indexOf(':')))
+    {
+        bSuccess &= lcl_parseDate(isNegative, nYear, nMonth, nDay,
+                bHaveTime, nPos, string, bIgnoreInvalidOrMissingDate);
+    }
+    else
+    {
+        bHaveTime = true;
+    }
+
+    sal_Int32 nHours(0);
+    sal_Int32 nMinutes(0);
+    sal_Int32 nSeconds(0);
+    sal_Int32 nNanoSeconds(0);
+    if (bSuccess && bHaveTime)
+    {
+        {
+            bSuccess = readDateTimeComponent(string, nPos, nHours, 2, true);
+            bSuccess &= (0 <= nHours) && (nHours <= 24);
+            bSuccess &= (nPos < string.getLength()); // not last token
+        }
+        if (bSuccess && (':' != string[nPos])) // separator
+        {
+            bSuccess = false;
+        }
+        if (bSuccess)
+        {
+            ++nPos;
+
+            bSuccess = readDateTimeComponent(string, nPos, nMinutes, 2, true);
+            bSuccess &= (0 <= nMinutes) && (nMinutes < 60);
+            bSuccess &= (nPos < string.getLength()); // not last token
+        }
+        if (bSuccess && (':' != string[nPos])) // separator
+        {
+            bSuccess = false;
+        }
+        if (bSuccess)
+        {
+            ++nPos;
+
+            bSuccess = readDateTimeComponent(string, nPos, nSeconds, 2, true);
+            bSuccess &= (0 <= nSeconds) && (nSeconds < 60);
+        }
+        if (bSuccess && (nPos < string.getLength()) &&
+            ('.' == string[nPos] || ',' == string[nPos])) // fraction separator
+        {
+            ++nPos;
+            const sal_Int32 nStart(nPos);
+            sal_Int32 nTemp(0);
+            if (R_NOTHING == readUnsignedNumberMaxDigits(9, string, nPos, nTemp))
+            {
+                bSuccess = false;
+            }
+            if (bSuccess)
+            {
+                sal_Int32 nDigits = std::min<sal_Int32>(nPos - nStart, 9);
+                assert(nDigits > 0);
+                for (; nDigits < 9; ++nDigits)
+                {
+                    nTemp *= 10;
+                }
+                nNanoSeconds = nTemp;
+            }
+        }
+
+        if (bSuccess && (nHours == 24))
+        {
+            if (!((0 == nMinutes) && (0 == nSeconds) && (0 == nNanoSeconds)))
+            {
+                bSuccess = false; // only 24:00:00 is valid
+            }
+        }
+    }
+
+    bool bHaveTimezone(false);
+    bool bHaveTimezonePlus(false);
+    bool bHaveTimezoneMinus(false);
+    if (bSuccess && (nPos < string.getLength()))
+    {
+        const sal_Unicode c(string[nPos]);
+        if ('+' == c)
+        {
+            bHaveTimezone = true;
+            bHaveTimezonePlus = true;
+            ++nPos;
+        }
+        else if ('-' == c)
+        {
+            bHaveTimezone = true;
+            bHaveTimezoneMinus = true;
+            ++nPos;
+        }
+        else if ('Z' == c)
+        {
+            bHaveTimezone = true;
+            ++nPos;
+        }
+        else
+        {
+            bSuccess = false;
+        }
+    }
+    sal_Int32 nTimezoneHours(0);
+    sal_Int32 nTimezoneMinutes(0);
+    if (bSuccess && (bHaveTimezonePlus || bHaveTimezoneMinus))
+    {
+        bSuccess = readDateTimeComponent(
+                        string, nPos, nTimezoneHours, 2, true);
+        bSuccess &= (0 <= nTimezoneHours) && (nTimezoneHours <= 14);
+        bSuccess &= (nPos < string.getLength()); // not last token
+        if (bSuccess && (':' != string[nPos])) // separator
+        {
+            bSuccess = false;
+        }
+        if (bSuccess)
+        {
+            ++nPos;
+
+            bSuccess = readDateTimeComponent(
+                        string, nPos, nTimezoneMinutes, 2, true);
+            bSuccess &= (0 <= nTimezoneMinutes) && (nTimezoneMinutes < 60);
+        }
+        if (bSuccess && (nTimezoneHours == 14))
+        {
+            if (0 != nTimezoneMinutes)
+            {
+                bSuccess = false; // only +-14:00 is valid
+            }
+        }
+    }
+
+    bSuccess &= (nPos == string.getLength()); // trailing junk?
+
+    if (bSuccess)
+    {
+        sal_Int16 const nTimezoneOffset = (bHaveTimezoneMinus ? -1 : +1)
+                        * ((nTimezoneHours * 60) + nTimezoneMinutes);
+        if (!pDate || bHaveTime) // time is optional
+        {
+            rDateTime.Year =
+                (isNegative ? -1 : +1) * static_cast<sal_Int16>(nYear);
+            rDateTime.Month = static_cast<sal_uInt16>(nMonth);
+            rDateTime.Day = static_cast<sal_uInt16>(nDay);
+            rDateTime.Hours = static_cast<sal_uInt16>(nHours);
+            rDateTime.Minutes = static_cast<sal_uInt16>(nMinutes);
+            rDateTime.Seconds = static_cast<sal_uInt16>(nSeconds);
+            rDateTime.NanoSeconds = static_cast<sal_uInt32>(nNanoSeconds);
+            if (bHaveTimezone)
+            {
+                if (pTimeZoneOffset)
+                {
+                    *pTimeZoneOffset = nTimezoneOffset;
+                    rDateTime.IsUTC = (0 == nTimezoneOffset);
+                }
+                else
+                {
+                    lcl_ConvertToUTC(rDateTime.Year, rDateTime.Month,
+                            rDateTime.Day, rDateTime.Hours, rDateTime.Minutes,
+                            nTimezoneOffset);
+                    rDateTime.IsUTC = true;
+                }
+            }
+            else
+            {
+                if (pTimeZoneOffset)
+                {
+                    pTimeZoneOffset->reset();
+                }
+                rDateTime.IsUTC = false;
+            }
+            rbDateTime = bHaveTime;
+        }
+        else
+        {
+            pDate->Year =
+                (isNegative ? -1 : +1) * static_cast<sal_Int16>(nYear);
+            pDate->Month = static_cast<sal_uInt16>(nMonth);
+            pDate->Day = static_cast<sal_uInt16>(nDay);
+            if (bHaveTimezone)
+            {
+                if (pTimeZoneOffset)
+                {
+                    *pTimeZoneOffset = nTimezoneOffset;
+                }
+                else
+                {
+                    // a Date cannot be adjusted
+                    SAL_INFO("sax", "dropping timezone");
+                }
+            }
+            else
+            {
+                if (pTimeZoneOffset)
+                {
+                    pTimeZoneOffset->reset();
+                }
+            }
+            rbDateTime = false;
+        }
+    }
+    return bSuccess;
+}
+
+/** convert ISO "time" or "dateTime" string to util::DateTime */
+bool Converter::parseTimeOrDateTime(
+                util::DateTime & rDateTime,
+                const OUString & rString)
+{
+    bool dummy;
+    return lcl_parseDateTime(
+                nullptr, rDateTime, dummy, nullptr, rString, true);
+}
+
+/** convert ISO "date" or "dateTime" string to util::DateTime or util::Date */
+bool Converter::parseDateOrDateTime(
+                util::Date *const pDate, util::DateTime & rDateTime,
+                bool & rbDateTime,
+                std::optional<sal_Int16> *const pTimeZoneOffset,
+                const OUString & rString )
+{
+    return lcl_parseDateTime(
+                pDate, rDateTime, rbDateTime, pTimeZoneOffset, rString, false);
+}
+
+
+/** gets the position of the first comma after npos in the string
+    rStr. Commas inside '"' pairs are not matched */
+sal_Int32 Converter::indexOfComma( const OUString& rStr,
+                                            sal_Int32 nPos )
+{
+    sal_Unicode cQuote = 0;
+    sal_Int32 nLen = rStr.getLength();
+    for( ; nPos < nLen; nPos++ )
+    {
+        sal_Unicode c = rStr[nPos];
+        switch( c )
+        {
+        case u'\'':
+            if( 0 == cQuote )
+                cQuote = c;
+            else if( '\'' == cQuote )
+                cQuote = 0;
+            break;
+
+        case u'"':
+            if( 0 == cQuote )
+                cQuote = c;
+            else if( '\"' == cQuote )
+                cQuote = 0;
+            break;
+
+        case u',':
+            if( 0 == cQuote )
+                return nPos;
+            break;
+        }
+    }
+
+    return -1;
+}
+
+double Converter::GetConversionFactor(OUStringBuffer& rUnit, sal_Int16 nSourceUnit, sal_Int16 nTargetUnit)
+{
+    double fRetval(1.0);
+    rUnit.setLength(0);
+
+
+    if(nSourceUnit != nTargetUnit)
+    {
+        const char* psUnit = nullptr;
+
+        switch(nSourceUnit)
+        {
+            case MeasureUnit::TWIP:
+            {
+                switch(nTargetUnit)
+                {
+                    case MeasureUnit::MM_100TH:
+                    {
+                        // 0.01mm = 0.57twip (exactly)
+                        fRetval = ((25400.0 / 1440.0) / 10.0);
+                        break;
+                    }
+                    case MeasureUnit::MM_10TH:
+                    {
+                        // 0.01mm = 0.57twip (exactly)
+                        fRetval = ((25400.0 / 1440.0) / 100.0);
+                        break;
+                    }
+                    case MeasureUnit::MM:
+                    {
+                        // 0.01mm = 0.57twip (exactly)
+                        fRetval = ((25400.0 / 1440.0) / 1000.0);
+                        psUnit = gpsMM;
+                        break;
+                    }
+                    case MeasureUnit::CM:
+                    {
+                        // 0.001cm = 0.57twip (exactly)
+                        fRetval = ((25400.0 / 1440.0) / 10000.0);
+                        psUnit = gpsCM;
+                        break;
+                    }
+                    case MeasureUnit::POINT:
+                    {
+                        // 0.01pt = 0.2twip (exactly)
+                        fRetval = ((1000.0 / 20.0) / 1000.0);
+                        psUnit = gpsPT;
+                        break;
+                    }
+                    case MeasureUnit::INCH:
+                    default:
+                    {
+                        OSL_ENSURE( MeasureUnit::INCH == nTargetUnit, "output unit not supported for twip values");
+                        // 0.0001in = 0.144twip (exactly)
+                        fRetval = ((100000.0 / 1440.0) / 100000.0);
+                        psUnit = gpsINCH;
+                        break;
+                    }
+                }
+                break;
+            }
+            case MeasureUnit::POINT:
+            {
+                switch(nTargetUnit)
+                {
+                    case MeasureUnit::MM_100TH:
+                    {
+                        // 1mm = 72 / 25.4 pt (exactly)
+                        fRetval = ( 2540.0 / 72.0 );
+                        break;
+                    }
+                    case MeasureUnit::MM_10TH:
+                    {
+                        // 1mm = 72 / 25.4 pt (exactly)
+                        fRetval = ( 254.0 / 72.0 );
+                        break;
+                    }
+                    case MeasureUnit::MM:
+                    {
+                        // 1mm = 72 / 25.4 pt (exactly)
+                        fRetval = ( 25.4 / 72.0 );
+                        psUnit = gpsMM;
+                        break;
+
+                    }
+                    case MeasureUnit::CM:
+                    {
+                        // 1cm = 72 / 2.54 pt (exactly)
+                        fRetval = ( 2.54 / 72.0 );
+                        psUnit = gpsCM;
+                        break;
+                    }
+                    case MeasureUnit::TWIP:
+                    {
+                        // 1twip = 72 / 1440 pt (exactly)
+                        fRetval = 20.0;     // 1440.0 / 72.0
+                        psUnit = gpsPC;
+                        break;
+                    }
+                    case MeasureUnit::INCH:
+                    default:
+                    {
+                        OSL_ENSURE( MeasureUnit::INCH == nTargetUnit, "output unit not supported for pt values");
+                        // 1in = 72 pt (exactly)
+                        fRetval = ( 1.0 / 72.0 );
+                        psUnit = gpsINCH;
+                        break;
+                    }
+                }
+                break;
+            }
+            case MeasureUnit::MM_10TH:
+            {
+                switch(nTargetUnit)
+                {
+                    case MeasureUnit::MM_100TH:
+                    {
+                        fRetval = 10.0;
+                        break;
+                    }
+                    case MeasureUnit::MM:
+                    {
+                        // 0.01mm = 1 mm/100 (exactly)
+                        fRetval = ((10.0 / 1.0) / 100.0);
+                        psUnit = gpsMM;
+                        break;
+                    }
+                    case MeasureUnit::CM:
+                    {
+                        fRetval = ((10.0 / 1.0) / 1000.0);
+                        psUnit = gpsCM;
+                        break;
+                    }
+                    case MeasureUnit::POINT:
+                    {
+                        // 0.01pt = 0.35 mm/100 (exactly)
+                        fRetval = ((72000.0 / 2540.0) / 100.0);
+                        psUnit = gpsPT;
+                        break;
+                    }
+                    case MeasureUnit::TWIP:
+                    {
+                        fRetval = ((20.0 * 72000.0 / 2540.0) / 100.0);
+                        psUnit = gpsPC;
+                        break;
+                    }
+                    case MeasureUnit::INCH:
+                    default:
+                    {
+                        OSL_ENSURE( MeasureUnit::INCH == nTargetUnit, "output unit not supported for 1/10mm values");
+                        // 0.0001in = 0.254 mm/100 (exactly)
+                        fRetval = ((100000.0 / 2540.0) / 10000.0);
+                        psUnit = gpsINCH;
+                        break;
+                    }
+                }
+                break;
+            }
+            case MeasureUnit::MM_100TH:
+            {
+                switch(nTargetUnit)
+                {
+                    case MeasureUnit::MM_10TH:
+                    {
+                        fRetval = ((10.0 / 1.0) / 100.0);
+                        break;
+                    }
+                    case MeasureUnit::MM:
+                    {
+                        // 0.01mm = 1 mm/100 (exactly)
+                        fRetval = ((10.0 / 1.0) / 1000.0);
+                        psUnit = gpsMM;
+                        break;
+                    }
+                    case MeasureUnit::CM:
+                    {
+                        fRetval = ((10.0 / 1.0) / 10000.0);
+                        psUnit = gpsCM;
+                        break;
+                    }
+                    case MeasureUnit::POINT:
+                    {
+                        // 0.01pt = 0.35 mm/100 (exactly)
+                        fRetval = ((72000.0 / 2540.0) / 1000.0);
+                        psUnit = gpsPT;
+                        break;
+                    }
+                    case MeasureUnit::TWIP:
+                    {
+                        fRetval = ((20.0 * 72000.0 / 2540.0) / 1000.0);
+                        psUnit = gpsPC;
+                        break;
+                    }
+                    case MeasureUnit::INCH:
+                    default:
+                    {
+                        OSL_ENSURE( MeasureUnit::INCH == nTargetUnit, "output unit not supported for 1/100mm values");
+                        // 0.0001in = 0.254 mm/100 (exactly)
+                        fRetval = ((100000.0 / 2540.0) / 100000.0);
+                        psUnit = gpsINCH;
+                        break;
+                    }
+                }
+                break;
+            }
+            case MeasureUnit::MM:
+            {
+                switch(nTargetUnit)
+                {
+                    case MeasureUnit::MM_100TH:
+                    {
+                        fRetval = 100.0;
+                        break;
+                    }
+                    case MeasureUnit::MM_10TH:
+                    {
+                        fRetval = 10.0;
+                        break;
+                    }
+                    case MeasureUnit::CM:
+                    {
+                        fRetval = 0.1;
+                        psUnit = gpsCM;
+                        break;
+                    }
+                    case MeasureUnit::POINT:
+                    {
+                        fRetval = 72.0 / (2.54 * 10);
+                        psUnit = gpsPT;
+                        break;
+                    }
+                    case MeasureUnit::TWIP:
+                    {
+                        fRetval = (20.0 * 72.0) / (2.54 * 10);
+                        psUnit = gpsPC;
+                        break;
+                    }
+                    case MeasureUnit::INCH:
+                    default:
+                    {
+                        OSL_ENSURE( MeasureUnit::INCH == nTargetUnit, "output unit not supported for cm values");
+                        fRetval = 1 / (2.54 * 10);
+                        psUnit = gpsINCH;
+                        break;
+                    }
+                }
+                break;
+            }
+            case MeasureUnit::CM:
+            {
+                switch(nTargetUnit)
+                {
+                    case MeasureUnit::MM_100TH:
+                    {
+                        fRetval = 1000.0;
+                        break;
+                    }
+                    case MeasureUnit::MM_10TH:
+                    {
+                        fRetval = 100.0;
+                        break;
+                    }
+                    case MeasureUnit::MM:
+                    {
+                        fRetval = 10.0;
+                        psUnit = gpsMM;
+                        break;
+                    }
+                    case MeasureUnit::CM:
+                    {
+                        break;
+                    }
+                    case MeasureUnit::POINT:
+                    {
+                        fRetval = 72.0 / 2.54;
+                        psUnit = gpsPT;
+                        break;
+                    }
+                    case MeasureUnit::TWIP:
+                    {
+                        fRetval = (20.0 * 72.0) / 2.54;
+                        psUnit = gpsPC;
+                        break;
+                    }
+                    case MeasureUnit::INCH:
+                    default:
+                    {
+                        OSL_ENSURE( MeasureUnit::INCH == nTargetUnit, "output unit not supported for cm values");
+                        fRetval = 1 / 2.54;
+                        psUnit = gpsINCH;
+                        break;
+                    }
+                }
+                break;
+            }
+            case MeasureUnit::INCH:
+            {
+                switch (nTargetUnit)
+                {
+                    case MeasureUnit::MM_100TH:
+                    {
+                        fRetval = 2540;
+                        break;
+                    }
+                    case MeasureUnit::MM_10TH:
+                    {
+                        fRetval = 254;
+                        break;
+                    }
+                    case MeasureUnit::MM:
+                    {
+                        fRetval = 25.4;
+                        psUnit = gpsMM;
+                        break;
+                    }
+                    case MeasureUnit::CM:
+                    {
+                        fRetval = 2.54;
+                        psUnit = gpsCM;
+                        break;
+                    }
+                    case MeasureUnit::POINT:
+                    {
+                        fRetval = 72.0;
+                        psUnit = gpsPT;
+                        break;
+                    }
+                    case MeasureUnit::TWIP:
+                    {
+                        fRetval = 72.0 * 20.0;
+                        psUnit = gpsPC;
+                        break;
+                    }
+                    default:
+                    {
+                        OSL_FAIL("output unit not supported for in values");
+                        fRetval = 1;
+                        psUnit = gpsINCH;
+                        break;
+                    }
+                }
+                break;
+            }
+            default:
+                OSL_ENSURE(false, "sax::Converter::GetConversionFactor(): "
+                        "source unit not supported");
+                break;
+        }
+
+        if( psUnit )
+            rUnit.appendAscii( psUnit );
+    }
+
+    return fRetval;
+}
+
+sal_Int16 Converter::GetUnitFromString(const OUString& rString, sal_Int16 nDefaultUnit)
+{
+    sal_Int32 nPos = 0;
+    sal_Int32 nLen = rString.getLength();
+    sal_Int16 nRetUnit = nDefaultUnit;
+
+    // skip white space
+    while( nPos < nLen && ' ' == rString[nPos] )
+        nPos++;
+
+    // skip negative
+    if( nPos < nLen && '-' == rString[nPos] )
+        nPos++;
+
+    // skip number
+    while( nPos < nLen && '0' <= rString[nPos] && '9' >= rString[nPos] )
+        nPos++;
+
+    if( nPos < nLen && '.' == rString[nPos] )
+    {
+        nPos++;
+        while( nPos < nLen && '0' <= rString[nPos] && '9' >= rString[nPos] )
+            nPos++;
+    }
+
+    // skip white space
+    while( nPos < nLen && ' ' == rString[nPos] )
+        nPos++;
+
+    if( nPos < nLen )
+    {
+        switch(rString[nPos])
+        {
+            case u'%' :
+            {
+                nRetUnit = MeasureUnit::PERCENT;
+                break;
+            }
+            case u'c':
+            case u'C':
+            {
+                if(nPos+1 < nLen && (rString[nPos+1] == 'm'
+                    || rString[nPos+1] == 'M'))
+                    nRetUnit = MeasureUnit::CM;
+                break;
+            }
+            case u'e':
+            case u'E':
+            {
+                // CSS1_EMS or CSS1_EMX later
+                break;
+            }
+            case u'i':
+            case u'I':
+            {
+                if(nPos+1 < nLen && (rString[nPos+1] == 'n'
+                    || rString[nPos+1] == 'N'))
+                    nRetUnit = MeasureUnit::INCH;
+                break;
+            }
+            case u'm':
+            case u'M':
+            {
+                if(nPos+1 < nLen && (rString[nPos+1] == 'm'
+                    || rString[nPos+1] == 'M'))
+                    nRetUnit = MeasureUnit::MM;
+                break;
+            }
+            case u'p':
+            case u'P':
+            {
+                if(nPos+1 < nLen && (rString[nPos+1] == 't'
+                    || rString[nPos+1] == 'T'))
+                    nRetUnit = MeasureUnit::POINT;
+                if(nPos+1 < nLen && (rString[nPos+1] == 'c'
+                    || rString[nPos+1] == 'C'))
+                    nRetUnit = MeasureUnit::TWIP;
+                break;
+            }
+        }
+    }
+
+    return nRetUnit;
+}
+
+
+bool Converter::convertAny(OUStringBuffer&    rsValue,
+                           OUStringBuffer&    rsType ,
+                           const css::uno::Any& rValue)
+{
+    bool bConverted = false;
+
+    rsValue.setLength(0);
+    rsType.setLength (0);
+
+    switch (rValue.getValueTypeClass())
+    {
+        case css::uno::TypeClass_BYTE :
+        case css::uno::TypeClass_SHORT :
+        case css::uno::TypeClass_UNSIGNED_SHORT :
+        case css::uno::TypeClass_LONG :
+        case css::uno::TypeClass_UNSIGNED_LONG :
+            {
+                sal_Int32 nTempValue = 0;
+                if (rValue >>= nTempValue)
+                {
+                    rsType.append("integer");
+                    bConverted = true;
+                    rsValue.append(nTempValue);
+                }
+            }
+            break;
+
+        case css::uno::TypeClass_BOOLEAN :
+            {
+                bool bTempValue = false;
+                if (rValue >>= bTempValue)
+                {
+                    rsType.append("boolean");
+                    bConverted = true;
+                    ::sax::Converter::convertBool(rsValue, bTempValue);
+                }
+            }
+            break;
+
+        case css::uno::TypeClass_FLOAT :
+        case css::uno::TypeClass_DOUBLE :
+            {
+                double fTempValue = 0.0;
+                if (rValue >>= fTempValue)
+                {
+                    rsType.append("float");
+                    bConverted = true;
+                    ::sax::Converter::convertDouble(rsValue, fTempValue);
+                }
+            }
+            break;
+
+        case css::uno::TypeClass_STRING :
+            {
+                OUString sTempValue;
+                if (rValue >>= sTempValue)
+                {
+                    rsType.append("string");
+                    bConverted = true;
+                    rsValue.append(sTempValue);
+                }
+            }
+            break;
+
+        case css::uno::TypeClass_STRUCT :
+            {
+                css::util::Date     aDate    ;
+                css::util::Time     aTime    ;
+                css::util::DateTime aDateTime;
+
+                if (rValue >>= aDate)
+                {
+                    rsType.append("date");
+                    bConverted = true;
+                    css::util::DateTime aTempValue;
+                    aTempValue.Day              = aDate.Day;
+                    aTempValue.Month            = aDate.Month;
+                    aTempValue.Year             = aDate.Year;
+                    aTempValue.NanoSeconds = 0;
+                    aTempValue.Seconds          = 0;
+                    aTempValue.Minutes          = 0;
+                    aTempValue.Hours            = 0;
+                    ::sax::Converter::convertDateTime(rsValue, aTempValue, nullptr);
+                }
+                else
+                if (rValue >>= aTime)
+                {
+                    rsType.append("time");
+                    bConverted = true;
+                    css::util::Duration aTempValue;
+                    aTempValue.Days             = 0;
+                    aTempValue.Months           = 0;
+                    aTempValue.Years            = 0;
+                    aTempValue.NanoSeconds     = aTime.NanoSeconds;
+                    aTempValue.Seconds          = aTime.Seconds;
+                    aTempValue.Minutes          = aTime.Minutes;
+                    aTempValue.Hours            = aTime.Hours;
+                    ::sax::Converter::convertDuration(rsValue, aTempValue);
+                }
+                else
+                if (rValue >>= aDateTime)
+                {
+                    rsType.append("date");
+                    bConverted = true;
+                    ::sax::Converter::convertDateTime(rsValue, aDateTime, nullptr);
+                }
+            }
+            break;
+        default:
+            break;
+    }
+
+    return bConverted;
+}
+
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sax/source/tools/fastattribs.cxx b/sax/source/tools/fastattribs.cxx
new file mode 100644
index 000000000..3df391c86
--- /dev/null
+++ b/sax/source/tools/fastattribs.cxx
@@ -0,0 +1,281 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <algorithm>
+
+#include <com/sun/star/xml/sax/SAXException.hpp>
+#include <com/sun/star/xml/sax/XFastTokenHandler.hpp>
+#include <sax/fastattribs.hxx>
+
+using namespace ::com::sun::star::uno;
+using namespace ::com::sun::star::xml;
+using namespace ::com::sun::star::xml::sax;
+namespace sax_fastparser
+{
+
+// wastage to keep MSVC happy vs. an in-line {}
+FastTokenHandlerBase::~FastTokenHandlerBase()
+{
+}
+
+UnknownAttribute::UnknownAttribute( const OUString& rNamespaceURL, const OString& rName, const OString& value )
+    : maNamespaceURL( rNamespaceURL ), maName( rName ), maValue( value )
+{
+}
+
+UnknownAttribute::UnknownAttribute( const OString& rName, const OString& value )
+    : maName( rName ), maValue( value )
+{
+}
+
+void UnknownAttribute::FillAttribute( Attribute* pAttrib ) const
+{
+    if( pAttrib )
+    {
+        pAttrib->Name = OStringToOUString( maName, RTL_TEXTENCODING_UTF8 );
+        pAttrib->NamespaceURL = maNamespaceURL;
+        pAttrib->Value = OStringToOUString( maValue, RTL_TEXTENCODING_UTF8 );
+    }
+}
+
+FastAttributeList::FastAttributeList( sax_fastparser::FastTokenHandlerBase *pTokenHandler)
+: mpTokenHandler( pTokenHandler )
+{
+    // random initial size of buffer to store attribute values
+    mnChunkLength = 58;
+    mpChunk = static_cast<char *>(malloc( mnChunkLength ));
+    maAttributeValues.push_back( 0 );
+}
+
+FastAttributeList::~FastAttributeList()
+{
+    free( mpChunk );
+}
+
+void FastAttributeList::clear()
+{
+    maAttributeTokens.clear();
+    maAttributeValues.resize(1);
+    assert(maAttributeValues[0] == 0);
+    maUnknownAttributes.clear();
+}
+
+void FastAttributeList::add( sal_Int32 nToken, const char* pValue, size_t nValueLength )
+{
+    assert(nToken != -1);
+    maAttributeTokens.push_back( nToken );
+    sal_Int32 nWritePosition = maAttributeValues.back();
+    maAttributeValues.push_back( maAttributeValues.back() + nValueLength + 1 );
+    if (maAttributeValues.back() > mnChunkLength)
+    {
+        const sal_Int32 newLen = std::max(mnChunkLength * 2, maAttributeValues.back());
+        if (auto p = static_cast<char*>(realloc(mpChunk, newLen)))
+        {
+            mnChunkLength = newLen;
+            mpChunk = p;
+        }
+        else
+            throw std::bad_alloc();
+    }
+    strncpy(mpChunk + nWritePosition, pValue, nValueLength);
+    mpChunk[nWritePosition + nValueLength] = '\0';
+}
+
+void FastAttributeList::add( sal_Int32 nToken, const char* pValue )
+{
+    add( nToken, pValue, strlen( pValue ));
+}
+
+void FastAttributeList::add( sal_Int32 nToken, const OString& rValue )
+{
+    add( nToken, rValue.getStr(), rValue.getLength() );
+}
+
+void FastAttributeList::addNS( sal_Int32 nNamespaceToken, sal_Int32 nToken, const OString& rValue )
+{
+    sal_Int32 nCombinedToken = (nNamespaceToken << 16) | nToken;
+    add( nCombinedToken, rValue );
+}
+
+void FastAttributeList::addUnknown( const OUString& rNamespaceURL, const OString& rName, const OString& value )
+{
+    maUnknownAttributes.emplace_back( rNamespaceURL, rName, value );
+}
+
+void FastAttributeList::addUnknown( const OString& rName, const OString& value )
+{
+    maUnknownAttributes.emplace_back( rName, value );
+}
+
+// XFastAttributeList
+sal_Bool FastAttributeList::hasAttribute( ::sal_Int32 Token )
+{
+    for (sal_Int32 i : maAttributeTokens)
+        if (i == Token)
+            return true;
+
+    return false;
+}
+
+sal_Int32 FastAttributeList::getValueToken( ::sal_Int32 Token )
+{
+    for (size_t i = 0; i < maAttributeTokens.size(); ++i)
+        if (maAttributeTokens[i] == Token)
+            return FastTokenHandlerBase::getTokenFromChars(
+                       mpTokenHandler,
+                       getFastAttributeValue(i),
+                       AttributeValueLength( i ) );
+
+    throw SAXException("FastAttributeList::getValueToken: unknown token " + OUString::number(Token), nullptr, Any());
+}
+
+sal_Int32 FastAttributeList::getOptionalValueToken( ::sal_Int32 Token, ::sal_Int32 Default )
+{
+    for (size_t i = 0; i < maAttributeTokens.size(); ++i)
+        if (maAttributeTokens[i] == Token)
+            return FastTokenHandlerBase::getTokenFromChars(
+                       mpTokenHandler,
+                       getFastAttributeValue(i),
+                       AttributeValueLength( i ) );
+
+    return Default;
+}
+
+// performance sensitive shortcuts to avoid allocation ...
+bool FastAttributeList::getAsInteger( sal_Int32 nToken, sal_Int32 &rInt) const
+{
+    rInt = 0;
+    for (size_t i = 0; i < maAttributeTokens.size(); ++i)
+        if (maAttributeTokens[i] == nToken)
+        {
+            rInt = rtl_str_toInt32( getFastAttributeValue(i), 10 );
+            return true;
+        }
+    return false;
+}
+
+sal_Int32 FastAttributeList::getAsIntegerByIndex( sal_Int32 nTokenIndex ) const
+{
+    return rtl_str_toInt32( getFastAttributeValue(nTokenIndex), 10 );
+}
+
+bool FastAttributeList::getAsDouble( sal_Int32 nToken, double &rDouble) const
+{
+    rDouble = 0.0;
+    for (size_t i = 0; i < maAttributeTokens.size(); ++i)
+        if (maAttributeTokens[i] == nToken)
+        {
+            rDouble = rtl_str_toDouble( getFastAttributeValue(i) );
+            return true;
+        }
+    return false;
+}
+
+bool FastAttributeList::getAsChar( sal_Int32 nToken, const char*& rPos ) const
+{
+    for (size_t i = 0, n = maAttributeTokens.size(); i < n; ++i)
+    {
+        if (maAttributeTokens[i] != nToken)
+            continue;
+
+        sal_Int32 nOffset = maAttributeValues[i];
+        rPos = mpChunk + nOffset;
+        return true;
+    }
+
+    return false;
+}
+
+const char* FastAttributeList::getAsCharByIndex( sal_Int32 nTokenIndex ) const
+{
+    sal_Int32 nOffset = maAttributeValues[nTokenIndex];
+    return mpChunk + nOffset;
+}
+
+OUString FastAttributeList::getValue( ::sal_Int32 Token )
+{
+    for (size_t i = 0; i < maAttributeTokens.size(); ++i)
+        if (maAttributeTokens[i] == Token)
+            return OUString( getFastAttributeValue(i), AttributeValueLength(i), RTL_TEXTENCODING_UTF8 );
+
+    throw SAXException("FastAttributeList::getValue: unknown token " + OUString::number(Token), nullptr, Any());
+}
+
+OUString FastAttributeList::getValueByIndex( ::sal_Int32 nTokenIndex ) const
+{
+    return OUString( getFastAttributeValue(nTokenIndex), AttributeValueLength(nTokenIndex), RTL_TEXTENCODING_UTF8 );
+}
+
+OUString FastAttributeList::getOptionalValue( ::sal_Int32 Token )
+{
+    for (size_t i = 0; i < maAttributeTokens.size(); ++i)
+        if (maAttributeTokens[i] == Token)
+            return OUString( getFastAttributeValue(i), AttributeValueLength(i), RTL_TEXTENCODING_UTF8 );
+
+    return OUString();
+}
+Sequence< Attribute > FastAttributeList::getUnknownAttributes(  )
+{
+    auto nSize = maUnknownAttributes.size();
+    if (nSize == 0)
+        return {};
+    Sequence< Attribute > aSeq( nSize );
+    Attribute* pAttr = aSeq.getArray();
+    for( const auto& rAttr : maUnknownAttributes )
+        rAttr.FillAttribute( pAttr++ );
+    return aSeq;
+}
+Sequence< FastAttribute > FastAttributeList::getFastAttributes(  )
+{
+    Sequence< FastAttribute > aSeq( maAttributeTokens.size() );
+    FastAttribute* pAttr = aSeq.getArray();
+    for (size_t i = 0; i < maAttributeTokens.size(); ++i)
+    {
+        pAttr->Token = maAttributeTokens[i];
+        pAttr->Value = OUString( getFastAttributeValue(i), AttributeValueLength(i), RTL_TEXTENCODING_UTF8 );
+        pAttr++;
+    }
+    return aSeq;
+}
+
+FastAttributeList::FastAttributeIter FastAttributeList::find( sal_Int32 nToken ) const
+{
+    for (size_t i = 0; i < maAttributeTokens.size(); ++i)
+        if( maAttributeTokens[i] == nToken )
+            return FastAttributeIter(*this, i);
+    return end();
+}
+
+sal_Int32 FastTokenHandlerBase::getTokenFromChars(
+        const FastTokenHandlerBase *pTokenHandler,
+        const char *pToken, size_t nLen /* = 0 */ )
+{
+    sal_Int32 nRet;
+
+    if( !nLen )
+        nLen = strlen( pToken );
+
+    nRet = pTokenHandler->getTokenDirect( pToken, static_cast<sal_Int32>(nLen) );
+
+    return nRet;
+}
+
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sax/source/tools/fastserializer.cxx b/sax/source/tools/fastserializer.cxx
new file mode 100644
index 000000000..202641999
--- /dev/null
+++ b/sax/source/tools/fastserializer.cxx
@@ -0,0 +1,813 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include "fastserializer.hxx"
+
+#include <com/sun/star/xml/sax/FastTokenHandler.hpp>
+#include <rtl/math.h>
+#include <sal/log.hxx>
+#include <comphelper/processfactory.hxx>
+#include <comphelper/sequence.hxx>
+
+#include <string.h>
+
+#if OSL_DEBUG_LEVEL > 0
+#include <iostream>
+#include <set>
+#endif
+
+using ::std::vector;
+using ::com::sun::star::uno::Sequence;
+using ::com::sun::star::io::XOutputStream;
+
+#define HAS_NAMESPACE(x) ((x & 0xffff0000) != 0)
+#define NAMESPACE(x) (x >> 16)
+#define TOKEN(x) (x & 0xffff)
+// number of characters without terminating 0
+#define N_CHARS(string) (SAL_N_ELEMENTS(string) - 1)
+
+static const char sClosingBracket[] = ">";
+static const char sSlashAndClosingBracket[] = "/>";
+static const char sColon[] = ":";
+static const char sOpeningBracket[] = "<";
+static const char sOpeningBracketAndSlash[] = "</";
+static const char sQuote[] = "\"";
+static const char sEqualSignAndQuote[] = "=\"";
+static const char sSpace[] = " ";
+static const char sXmlHeader[] = "<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"yes\"?>\n";
+
+namespace sax_fastparser {
+    FastSaxSerializer::FastSaxSerializer( const css::uno::Reference< css::io::XOutputStream >& xOutputStream )
+        : maCachedOutputStream()
+        , maMarkStack()
+        , mbMarkStackEmpty(true)
+        , mpDoubleStr(nullptr)
+        , mnDoubleStrCapacity(RTL_STR_MAX_VALUEOFDOUBLE)
+        , mbXescape(true)
+    {
+        rtl_string_new_WithLength(&mpDoubleStr, mnDoubleStrCapacity);
+        mxFastTokenHandler = css::xml::sax::FastTokenHandler::create(
+                ::comphelper::getProcessComponentContext());
+        assert(xOutputStream.is()); // cannot do anything without that
+        maCachedOutputStream.setOutputStream( xOutputStream );
+    }
+
+    FastSaxSerializer::~FastSaxSerializer()
+    {
+        rtl_string_release(mpDoubleStr);
+    }
+
+    void FastSaxSerializer::startDocument()
+    {
+        writeBytes(sXmlHeader, N_CHARS(sXmlHeader));
+    }
+
+    void FastSaxSerializer::write( double value )
+    {
+        rtl_math_doubleToString(
+            &mpDoubleStr, &mnDoubleStrCapacity, 0, value, rtl_math_StringFormat_G,
+            RTL_STR_MAX_VALUEOFDOUBLE - RTL_CONSTASCII_LENGTH("-x.E-xxx"), '.', nullptr,
+            0, true);
+
+        write(mpDoubleStr->buffer, mpDoubleStr->length);
+        // and "clear" the string
+        mpDoubleStr->length = 0;
+        mnDoubleStrCapacity = RTL_STR_MAX_VALUEOFDOUBLE;
+    }
+
+    void FastSaxSerializer::write( const OUString& sOutput, bool bEscape )
+    {
+        write( OUStringToOString(sOutput, RTL_TEXTENCODING_UTF8), bEscape );
+
+    }
+
+    void FastSaxSerializer::write( const OString& sOutput, bool bEscape )
+    {
+        write( sOutput.getStr(), sOutput.getLength(), bEscape );
+    }
+
+    /** Characters not allowed in XML 1.0
+        XML 1.1 would exclude only U+0000
+     */
+    static bool invalidChar( char c )
+    {
+        if (static_cast<unsigned char>(c) >= 0x20)
+            return false;
+
+        switch (c)
+        {
+            case 0x09:
+            case 0x0a:
+            case 0x0d:
+                return false;
+        }
+        return true;
+    }
+
+    static bool isHexDigit( char c )
+    {
+        return ('0' <= c && c <= '9') || ('A' <= c && c <= 'F') || ('a' <= c && c <= 'f');
+    }
+
+    void FastSaxSerializer::write( const char* pStr, sal_Int32 nLen, bool bEscape )
+    {
+        if (nLen == -1)
+            nLen = pStr ? strlen(pStr) : 0;
+
+        if (!bEscape)
+        {
+            writeBytes( pStr, nLen );
+            return;
+        }
+
+        bool bGood = true;
+        const sal_Int32 kXescapeLen = 7;
+        char bufXescape[kXescapeLen+1];
+        sal_Int32 nNextXescape = 0;
+        for (sal_Int32 i = 0; i < nLen; ++i)
+        {
+            char c = pStr[ i ];
+            switch( c )
+            {
+                case '<':   writeBytes( "&lt;", 4 );     break;
+                case '>':   writeBytes( "&gt;", 4 );     break;
+                case '&':   writeBytes( "&amp;", 5 );    break;
+                case '\'':  writeBytes( "&apos;", 6 );   break;
+                case '"':   writeBytes( "&quot;", 6 );   break;
+                case '\t':
+#if 0
+                            // Seems OOXML prefers the _xHHHH_ escape over the
+                            // entity in *some* cases, apparently in attribute
+                            // values but not in element data.
+                            // Would need to distinguish at a higher level.
+                            if (mbXescape)
+                            {
+                                snprintf( bufXescape, kXescapeLen+1, "_x%04x_",
+                                        static_cast<unsigned int>(static_cast<unsigned char>(c)));
+                                writeBytes( bufXescape, kXescapeLen);
+                            }
+                            else
+#endif
+                            {
+                                writeBytes( "&#9;", 4 );
+                            }
+                break;
+                case '\n':
+#if 0
+                            if (mbXescape)
+                            {
+                                snprintf( bufXescape, kXescapeLen+1, "_x%04x_",
+                                        static_cast<unsigned int>(static_cast<unsigned char>(c)));
+                                writeBytes( bufXescape, kXescapeLen);
+                            }
+                            else
+#endif
+                            {
+                                writeBytes( "&#10;", 5 );
+                            }
+                break;
+                case '\r':
+#if 0
+                            if (mbXescape)
+                            {
+                                snprintf( bufXescape, kXescapeLen+1, "_x%04x_",
+                                        static_cast<unsigned int>(static_cast<unsigned char>(c)));
+                                writeBytes( bufXescape, kXescapeLen);
+                            }
+                            else
+#endif
+                            {
+                                writeBytes( "&#13;", 5 );
+                            }
+                break;
+                default:
+                            if (mbXescape)
+                            {
+                                char c1, c2, c3, c4;
+                                // Escape characters not valid in XML 1.0 as
+                                // _xHHHH_. A literal "_xHHHH_" has to be
+                                // escaped as _x005F_xHHHH_ (effectively
+                                // escaping the leading '_').
+                                // See ECMA-376-1:2016 page 3736,
+                                // 22.4.2.4 bstr (Basic String)
+                                // for reference.
+                                if (c == '_' && i >= nNextXescape && i <= nLen - kXescapeLen &&
+                                        pStr[i+6] == '_' &&
+                                        ((pStr[i+1] | 0x20) == 'x') &&
+                                        isHexDigit( c1 = pStr[i+2] ) &&
+                                        isHexDigit( c2 = pStr[i+3] ) &&
+                                        isHexDigit( c3 = pStr[i+4] ) &&
+                                        isHexDigit( c4 = pStr[i+5] ))
+                                {
+                                    // OOXML has the odd habit to write some
+                                    // names using this that when re-saving
+                                    // should *not* be escaped, specifically
+                                    // _x0020_ for blanks in w:xpath values.
+                                    if (!(c1 == '0' && c2 == '0' && c3 == '2' && c4 == '0'))
+                                    {
+                                        // When encountering "_x005F_xHHHH_"
+                                        // assume that is an already escaped
+                                        // sequence that was not unescaped and
+                                        // shall be written as is, to not end
+                                        // up with "_x005F_x005F_xHHHH_" and
+                                        // repeated...
+                                        if (c1 == '0' && c2 == '0' && c3 == '5' && (c4 | 0x20) == 'f' &&
+                                                i + kXescapeLen <= nLen - 6 &&
+                                                pStr[i+kXescapeLen+5] == '_' &&
+                                                ((pStr[i+kXescapeLen+0] | 0x20) == 'x') &&
+                                                isHexDigit( pStr[i+kXescapeLen+1] ) &&
+                                                isHexDigit( pStr[i+kXescapeLen+2] ) &&
+                                                isHexDigit( pStr[i+kXescapeLen+3] ) &&
+                                                isHexDigit( pStr[i+kXescapeLen+4] ))
+                                        {
+                                            writeBytes( &c, 1 );
+                                            // Remember this fake escapement.
+                                            nNextXescape = i + kXescapeLen + 6;
+                                        }
+                                        else
+                                        {
+                                            writeBytes( "_x005F_", kXescapeLen);
+                                            // Remember this escapement so in
+                                            // _xHHHH_xHHHH_ only the first '_'
+                                            // is escaped.
+                                            nNextXescape = i + kXescapeLen;
+                                        }
+                                        break;
+                                    }
+                                }
+                                if (invalidChar(c))
+                                {
+                                    snprintf( bufXescape, kXescapeLen+1, "_x%04x_",
+                                            static_cast<unsigned int>(static_cast<unsigned char>(c)));
+                                    writeBytes( bufXescape, kXescapeLen);
+                                    break;
+                                }
+                                /* TODO: also U+FFFE and U+FFFF are not allowed
+                                 * in XML 1.0, assuming we're writing UTF-8
+                                 * those should be escaped as well to be
+                                 * conformant. Likely that would involve
+                                 * scanning for both encoded sequences and
+                                 * write as _xHHHH_? */
+                            }
+#if OSL_DEBUG_LEVEL > 0
+                            else
+                            {
+                                if (bGood && invalidChar(pStr[i]))
+                                {
+                                    bGood = false;
+                                    // The SAL_WARN() for the single character is
+                                    // issued in writeBytes(), just gather for the
+                                    // SAL_WARN_IF() below.
+                                }
+                            }
+#endif
+                            writeBytes( &c, 1 );
+                break;
+            }
+        }
+        SAL_WARN_IF( !bGood && nLen > 1, "sax", "in '" << OString(pStr,std::min<sal_Int32>(nLen,42)) << "'");
+    }
+
+    void FastSaxSerializer::endDocument()
+    {
+        assert(mbMarkStackEmpty && maMarkStack.empty());
+        maCachedOutputStream.flush();
+    }
+
+    void FastSaxSerializer::writeId( ::sal_Int32 nElement )
+    {
+        if( HAS_NAMESPACE( nElement ) ) {
+            auto const Namespace(mxFastTokenHandler->getUTF8Identifier(NAMESPACE(nElement)));
+            assert(Namespace.hasElements());
+            writeBytes(Namespace);
+            writeBytes(sColon, N_CHARS(sColon));
+            auto const Element(mxFastTokenHandler->getUTF8Identifier(TOKEN(nElement)));
+            assert(Element.hasElements());
+            writeBytes(Element);
+        } else {
+            auto const Element(mxFastTokenHandler->getUTF8Identifier(nElement));
+            assert(Element.hasElements());
+            writeBytes(Element);
+        }
+    }
+
+#ifdef DBG_UTIL
+    OString FastSaxSerializer::getId( ::sal_Int32 nElement )
+    {
+        if (HAS_NAMESPACE(nElement)) {
+            Sequence<sal_Int8> const ns(
+                mxFastTokenHandler->getUTF8Identifier(NAMESPACE(nElement)));
+            Sequence<sal_Int8> const name(
+                mxFastTokenHandler->getUTF8Identifier(TOKEN(nElement)));
+            return OString(reinterpret_cast<char const*>(ns.getConstArray()), ns.getLength())
+                 + OString(sColon, N_CHARS(sColon))
+                 + OString(reinterpret_cast<char const*>(name.getConstArray()), name.getLength());
+        } else {
+            Sequence<sal_Int8> const name(
+                mxFastTokenHandler->getUTF8Identifier(nElement));
+            return OString(reinterpret_cast<char const*>(name.getConstArray()), name.getLength());
+        }
+    }
+#endif
+
+    void FastSaxSerializer::startFastElement( ::sal_Int32 Element, FastAttributeList const * pAttrList )
+    {
+        if ( !mbMarkStackEmpty )
+        {
+            maCachedOutputStream.flush();
+            maMarkStack.top()->setCurrentElement( Element );
+        }
+
+#ifdef DBG_UTIL
+        if (mbMarkStackEmpty)
+            m_DebugStartedElements.push(Element);
+        else
+            maMarkStack.top()->m_DebugStartedElements.push_back(Element);
+#endif
+
+        writeBytes(sOpeningBracket, N_CHARS(sOpeningBracket));
+
+        writeId(Element);
+        if (pAttrList)
+            writeFastAttributeList(*pAttrList);
+        else
+            writeTokenValueList();
+
+        writeBytes(sClosingBracket, N_CHARS(sClosingBracket));
+    }
+
+    void FastSaxSerializer::endFastElement( ::sal_Int32 Element )
+    {
+#ifdef DBG_UTIL
+        // Well-formedness constraint: Element Type Match
+        if (mbMarkStackEmpty)
+        {
+            assert(!m_DebugStartedElements.empty());
+            assert(Element == m_DebugStartedElements.top());
+            m_DebugStartedElements.pop();
+        }
+        else
+        {
+            if (dynamic_cast<ForSort*>(maMarkStack.top().get()))
+            {
+                // Sort is always well-formed fragment
+                assert(!maMarkStack.top()->m_DebugStartedElements.empty());
+            }
+            if (maMarkStack.top()->m_DebugStartedElements.empty())
+            {
+                maMarkStack.top()->m_DebugEndedElements.push_back(Element);
+            }
+            else
+            {
+                assert(Element == maMarkStack.top()->m_DebugStartedElements.back());
+                maMarkStack.top()->m_DebugStartedElements.pop_back();
+            }
+        }
+#endif
+
+        writeBytes(sOpeningBracketAndSlash, N_CHARS(sOpeningBracketAndSlash));
+
+        writeId(Element);
+
+        writeBytes(sClosingBracket, N_CHARS(sClosingBracket));
+    }
+
+    void FastSaxSerializer::singleFastElement( ::sal_Int32 Element, FastAttributeList const * pAttrList )
+    {
+        if ( !mbMarkStackEmpty )
+        {
+            maCachedOutputStream.flush();
+            maMarkStack.top()->setCurrentElement( Element );
+        }
+
+        writeBytes(sOpeningBracket, N_CHARS(sOpeningBracket));
+
+        writeId(Element);
+        if (pAttrList)
+            writeFastAttributeList(*pAttrList);
+        else
+            writeTokenValueList();
+
+        writeBytes(sSlashAndClosingBracket, N_CHARS(sSlashAndClosingBracket));
+    }
+
+    css::uno::Reference< css::io::XOutputStream > const & FastSaxSerializer::getOutputStream() const
+    {
+        return maCachedOutputStream.getOutputStream();
+    }
+
+    void FastSaxSerializer::writeTokenValueList()
+    {
+#ifdef DBG_UTIL
+        ::std::set<OString> DebugAttributes;
+#endif
+        for (const TokenValue & rTokenValue : maTokenValues)
+        {
+            writeBytes(sSpace, N_CHARS(sSpace));
+
+            sal_Int32 nToken = rTokenValue.nToken;
+            writeId(nToken);
+
+#ifdef DBG_UTIL
+            // Well-formedness constraint: Unique Att Spec
+            OString const nameId(getId(nToken));
+            assert(DebugAttributes.find(nameId) == DebugAttributes.end());
+            DebugAttributes.insert(nameId);
+#endif
+
+            writeBytes(sEqualSignAndQuote, N_CHARS(sEqualSignAndQuote));
+
+            write(rTokenValue.pValue, -1, true);
+
+            writeBytes(sQuote, N_CHARS(sQuote));
+        }
+        maTokenValues.clear();
+    }
+
+    void FastSaxSerializer::writeFastAttributeList(FastAttributeList const & rAttrList)
+    {
+#ifdef DBG_UTIL
+        ::std::set<OString> DebugAttributes;
+#endif
+        const std::vector< sal_Int32 >& Tokens = rAttrList.getFastAttributeTokens();
+        for (size_t j = 0; j < Tokens.size(); j++)
+        {
+            writeBytes(sSpace, N_CHARS(sSpace));
+
+            sal_Int32 nToken = Tokens[j];
+            writeId(nToken);
+
+#ifdef DBG_UTIL
+            // Well-formedness constraint: Unique Att Spec
+            OString const nameId(getId(nToken));
+            SAL_WARN_IF(DebugAttributes.find(nameId) != DebugAttributes.end(),  "sax", "Duplicate attribute: " << nameId );
+            assert(DebugAttributes.find(nameId) == DebugAttributes.end());
+            DebugAttributes.insert(nameId);
+#endif
+
+            writeBytes(sEqualSignAndQuote, N_CHARS(sEqualSignAndQuote));
+
+            const char* pAttributeValue = rAttrList.getFastAttributeValue(j);
+
+            // tdf#127274 don't escape the special VML shape type id "#_x0000_t202"
+            bool bEscape = !(pAttributeValue && strcmp(pAttributeValue, "#_x0000_t202") == 0);
+
+            write(pAttributeValue, rAttrList.AttributeValueLength(j), bEscape);
+
+            writeBytes(sQuote, N_CHARS(sQuote));
+        }
+    }
+
+    void FastSaxSerializer::mark(sal_Int32 const nTag, const Int32Sequence& rOrder)
+    {
+        if (rOrder.hasElements())
+        {
+            auto pSort = std::make_shared<ForSort>(nTag, rOrder);
+            maMarkStack.push( pSort );
+            maCachedOutputStream.setOutput( pSort );
+        }
+        else
+        {
+            auto pMerge = std::make_shared<ForMerge>(nTag);
+            maMarkStack.push( pMerge );
+            maCachedOutputStream.setOutput( pMerge );
+        }
+        mbMarkStackEmpty = false;
+    }
+
+#ifdef DBG_UTIL
+    static void lcl_DebugMergeAppend(
+            std::deque<sal_Int32> & rLeftEndedElements,
+            std::deque<sal_Int32> & rLeftStartedElements,
+            std::deque<sal_Int32> & rRightEndedElements,
+            std::deque<sal_Int32> & rRightStartedElements)
+    {
+        while (!rRightEndedElements.empty())
+        {
+            if (rLeftStartedElements.empty())
+            {
+                rLeftEndedElements.push_back(rRightEndedElements.front());
+            }
+            else
+            {
+                assert(rLeftStartedElements.back() == rRightEndedElements.front());
+                rLeftStartedElements.pop_back();
+            }
+            rRightEndedElements.pop_front();
+        }
+        while (!rRightStartedElements.empty())
+        {
+            rLeftStartedElements.push_back(rRightStartedElements.front());
+            rRightStartedElements.pop_front();
+        }
+    }
+
+    static void lcl_DebugMergePrepend(
+            std::deque<sal_Int32> & rLeftEndedElements,
+            std::deque<sal_Int32> & rLeftStartedElements,
+            std::deque<sal_Int32> & rRightEndedElements,
+            std::deque<sal_Int32> & rRightStartedElements)
+    {
+        while (!rLeftStartedElements.empty())
+        {
+            if (rRightEndedElements.empty())
+            {
+                rRightStartedElements.push_front(rLeftStartedElements.back());
+            }
+            else
+            {
+                assert(rRightEndedElements.front() == rLeftStartedElements.back());
+                rRightEndedElements.pop_front();
+            }
+            rLeftStartedElements.pop_back();
+        }
+        while (!rLeftEndedElements.empty())
+        {
+            rRightEndedElements.push_front(rLeftEndedElements.back());
+            rLeftEndedElements.pop_back();
+        }
+    }
+#endif
+
+    void FastSaxSerializer::mergeTopMarks(
+        sal_Int32 const nTag, sax_fastparser::MergeMarks const eMergeType)
+    {
+        SAL_WARN_IF(mbMarkStackEmpty, "sax", "Empty mark stack - nothing to merge");
+        assert(!mbMarkStackEmpty); // should never happen
+        if ( mbMarkStackEmpty )
+            return;
+
+        assert(maMarkStack.top()->m_Tag == nTag && "mark/merge tag mismatch!");
+        (void) nTag;
+#ifdef DBG_UTIL
+        if (dynamic_cast<ForSort*>(maMarkStack.top().get()))
+        {
+            // Sort is always well-formed fragment
+            assert(maMarkStack.top()->m_DebugStartedElements.empty());
+            assert(maMarkStack.top()->m_DebugEndedElements.empty());
+        }
+        lcl_DebugMergeAppend(
+            maMarkStack.top()->m_DebugEndedElements,
+            maMarkStack.top()->m_DebugStartedElements,
+            maMarkStack.top()->m_DebugPostponedEndedElements,
+            maMarkStack.top()->m_DebugPostponedStartedElements);
+#endif
+
+        // flush, so that we get everything in getData()
+        maCachedOutputStream.flush();
+
+        if (maMarkStack.size() == 1)
+        {
+#ifdef DBG_UTIL
+            while (!maMarkStack.top()->m_DebugEndedElements.empty())
+            {
+                assert(maMarkStack.top()->m_DebugEndedElements.front() == m_DebugStartedElements.top());
+                maMarkStack.top()->m_DebugEndedElements.pop_front();
+                m_DebugStartedElements.pop();
+            }
+            while (!maMarkStack.top()->m_DebugStartedElements.empty())
+            {
+                m_DebugStartedElements.push(maMarkStack.top()->m_DebugStartedElements.front());
+                maMarkStack.top()->m_DebugStartedElements.pop_front();
+            }
+#endif
+            Sequence<sal_Int8> aSeq( maMarkStack.top()->getData() );
+            maMarkStack.pop();
+            mbMarkStackEmpty = true;
+            maCachedOutputStream.resetOutputToStream();
+            maCachedOutputStream.writeBytes( aSeq.getConstArray(), aSeq.getLength() );
+            return;
+        }
+
+#ifdef DBG_UTIL
+        ::std::deque<sal_Int32> topDebugStartedElements(maMarkStack.top()->m_DebugStartedElements);
+        ::std::deque<sal_Int32> topDebugEndedElements(maMarkStack.top()->m_DebugEndedElements);
+#endif
+        const Int8Sequence aMerge( maMarkStack.top()->getData() );
+        maMarkStack.pop();
+#ifdef DBG_UTIL
+        switch (eMergeType)
+        {
+            case MergeMarks::APPEND:
+                lcl_DebugMergeAppend(
+                    maMarkStack.top()->m_DebugEndedElements,
+                    maMarkStack.top()->m_DebugStartedElements,
+                    topDebugEndedElements,
+                    topDebugStartedElements);
+                break;
+            case MergeMarks::PREPEND:
+                if (dynamic_cast<ForSort*>(maMarkStack.top().get())) // argh...
+                {
+                    lcl_DebugMergeAppend(
+                        maMarkStack.top()->m_DebugEndedElements,
+                        maMarkStack.top()->m_DebugStartedElements,
+                        topDebugEndedElements,
+                        topDebugStartedElements);
+                }
+                else
+                {
+                    lcl_DebugMergePrepend(
+                        topDebugEndedElements,
+                        topDebugStartedElements,
+                        maMarkStack.top()->m_DebugEndedElements,
+                        maMarkStack.top()->m_DebugStartedElements);
+                }
+                break;
+            case MergeMarks::POSTPONE:
+                lcl_DebugMergeAppend(
+                    maMarkStack.top()->m_DebugPostponedEndedElements,
+                    maMarkStack.top()->m_DebugPostponedStartedElements,
+                    topDebugEndedElements,
+                    topDebugStartedElements);
+                break;
+        }
+#endif
+        if (maMarkStack.empty())
+        {
+            mbMarkStackEmpty = true;
+            maCachedOutputStream.resetOutputToStream();
+        }
+        else
+        {
+            maCachedOutputStream.setOutput( maMarkStack.top() );
+        }
+
+        switch ( eMergeType )
+        {
+            case MergeMarks::APPEND:   maMarkStack.top()->append( aMerge );   break;
+            case MergeMarks::PREPEND:  maMarkStack.top()->prepend( aMerge );  break;
+            case MergeMarks::POSTPONE: maMarkStack.top()->postpone( aMerge ); break;
+        }
+    }
+
+    void FastSaxSerializer::writeBytes( const Sequence< sal_Int8 >& rData )
+    {
+        maCachedOutputStream.writeBytes( rData.getConstArray(), rData.getLength() );
+    }
+
+    void FastSaxSerializer::writeBytes( const char* pStr, size_t nLen )
+    {
+#if OSL_DEBUG_LEVEL > 0
+        {
+            bool bGood = true;
+            for (size_t i=0; i < nLen; ++i)
+            {
+                if (invalidChar(pStr[i]))
+                {
+                    bGood = false;
+                    SAL_WARN("sax", "FastSaxSerializer::writeBytes - illegal XML character 0x" <<
+                            std::hex << int(static_cast<unsigned char>(pStr[i])));
+                }
+            }
+            SAL_WARN_IF( !bGood && nLen > 1, "sax", "in '" << OString(pStr,std::min<sal_Int32>(nLen,42)) << "'");
+        }
+#endif
+        maCachedOutputStream.writeBytes( reinterpret_cast<const sal_Int8*>(pStr), nLen );
+    }
+
+    FastSaxSerializer::Int8Sequence& FastSaxSerializer::ForMerge::getData()
+    {
+        merge( maData, maPostponed, true );
+        maPostponed.realloc( 0 );
+
+        return maData;
+    }
+
+#if OSL_DEBUG_LEVEL > 0
+    void FastSaxSerializer::ForMerge::print( )
+    {
+        std::cerr << "Data: ";
+        for ( sal_Int32 i=0, len=maData.getLength(); i < len; i++ )
+        {
+            std::cerr << maData[i];
+        }
+
+        std::cerr << "\nPostponed: ";
+        for ( sal_Int32 i=0, len=maPostponed.getLength(); i < len; i++ )
+        {
+            std::cerr << maPostponed[i];
+        }
+
+        std::cerr << "\n";
+    }
+#endif
+
+    void FastSaxSerializer::ForMerge::prepend( const Int8Sequence &rWhat )
+    {
+        merge( maData, rWhat, false );
+    }
+
+    void FastSaxSerializer::ForMerge::append( const css::uno::Sequence<sal_Int8> &rWhat )
+    {
+        merge( maData, rWhat, true );
+    }
+
+    void FastSaxSerializer::ForMerge::postpone( const Int8Sequence &rWhat )
+    {
+        merge( maPostponed, rWhat, true );
+    }
+
+    void FastSaxSerializer::ForMerge::merge( Int8Sequence &rTop, const Int8Sequence &rMerge, bool bAppend )
+    {
+        sal_Int32 nMergeLen = rMerge.getLength();
+        if ( nMergeLen <= 0 )
+            return;
+
+        sal_Int32 nTopLen = rTop.getLength();
+
+        rTop.realloc( nTopLen + nMergeLen );
+        if ( bAppend )
+        {
+            // append the rMerge to the rTop
+            memcpy( rTop.getArray() + nTopLen, rMerge.getConstArray(), nMergeLen );
+        }
+        else
+        {
+            // prepend the rMerge to the rTop
+            memmove( rTop.getArray() + nMergeLen, rTop.getConstArray(), nTopLen );
+            memcpy( rTop.getArray(), rMerge.getConstArray(), nMergeLen );
+        }
+    }
+
+    void FastSaxSerializer::ForMerge::resetData( )
+    {
+        maData = Int8Sequence();
+    }
+
+    void FastSaxSerializer::ForSort::setCurrentElement( sal_Int32 nElement )
+    {
+        vector< sal_Int32 > aOrder( comphelper::sequenceToContainer<vector<sal_Int32> >(maOrder) );
+        if( std::find( aOrder.begin(), aOrder.end(), nElement ) != aOrder.end() )
+        {
+            mnCurrentElement = nElement;
+            if ( maData.find( nElement ) == maData.end() )
+                maData[ nElement ] = Int8Sequence();
+        }
+    }
+
+    void FastSaxSerializer::ForSort::prepend( const Int8Sequence &rWhat )
+    {
+        append( rWhat );
+    }
+
+    void FastSaxSerializer::ForSort::append( const css::uno::Sequence<sal_Int8> &rWhat )
+    {
+        merge( maData[mnCurrentElement], rWhat, true );
+    }
+
+    void FastSaxSerializer::ForSort::sort()
+    {
+        // Clear the ForMerge data to avoid duplicate items
+        resetData();
+
+        // Sort it all
+        std::map< sal_Int32, Int8Sequence >::iterator iter;
+        for ( const auto nIndex : std::as_const(maOrder) )
+        {
+            iter = maData.find( nIndex );
+            if ( iter != maData.end() )
+                ForMerge::append( iter->second );
+        }
+    }
+
+    FastSaxSerializer::Int8Sequence& FastSaxSerializer::ForSort::getData()
+    {
+        sort( );
+        return ForMerge::getData();
+    }
+
+#if OSL_DEBUG_LEVEL > 0
+    void FastSaxSerializer::ForSort::print( )
+    {
+        for ( const auto& [rElement, rData] : maData )
+        {
+            std::cerr << "pair: " << rElement;
+            for ( sal_Int32 i=0, len=rData.getLength(); i < len; ++i )
+                std::cerr << rData[i];
+            std::cerr << "\n";
+        }
+
+        sort( );
+        ForMerge::print();
+    }
+#endif
+
+} // namespace sax_fastparser
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sax/source/tools/fastserializer.hxx b/sax/source/tools/fastserializer.hxx
new file mode 100644
index 000000000..0b7ad72d8
--- /dev/null
+++ b/sax/source/tools/fastserializer.hxx
@@ -0,0 +1,254 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#ifndef INCLUDED_SAX_SOURCE_TOOLS_FASTSERIALIZER_HXX
+#define INCLUDED_SAX_SOURCE_TOOLS_FASTSERIALIZER_HXX
+
+#include <com/sun/star/xml/sax/XFastTokenHandler.hpp>
+#include <com/sun/star/io/XOutputStream.hpp>
+
+#include <sax/fastattribs.hxx>
+#include <sax/fshelper.hxx>
+#include "CachedOutputStream.hxx"
+
+#include <stack>
+#include <map>
+#include <memory>
+
+namespace sax_fastparser {
+
+struct TokenValue
+{
+    sal_Int32   nToken;
+    const char *pValue;
+    TokenValue(sal_Int32 _nToken, const char *_pValue) : nToken(_nToken), pValue(_pValue) {}
+};
+typedef std::vector<TokenValue> TokenValueList;
+
+/// Receives notification of sax document events to write into an XOutputStream.
+class FastSaxSerializer
+{
+    typedef css::uno::Sequence< ::sal_Int8 > Int8Sequence;
+    typedef css::uno::Sequence< ::sal_Int32 > Int32Sequence;
+
+public:
+    explicit FastSaxSerializer(const css::uno::Reference< css::io::XOutputStream >& xOutputStream);
+    ~FastSaxSerializer();
+
+    css::uno::Reference< css::io::XOutputStream > const & getOutputStream() const;
+    /// called by FSHelper to put data in for writeTokenValueList
+    TokenValueList& getTokenValueList() { return maTokenValues; }
+
+    /** called by the parser when parsing of an XML stream is started.
+     */
+    void startDocument();
+
+    /** called by the parser after the last XML element of a stream is processed.
+     */
+    void endDocument();
+
+    /** receives notification of the beginning of an element.
+
+        @param Element
+            contains the integer token from the <type>XFastTokenHandler</type>
+            registered at the <type>XFastParser</type>.<br>
+
+            If the element has a namespace that was registered with the
+            <type>XFastParser</type>, <param>Element</param> contains the integer
+            token of the elements local name from the <type>XFastTokenHandler</type>
+            and the integer token of the namespace combined with an arithmetic
+            <b>or</b> operation.
+
+        @param pAttrList
+            Contains a <type>FastAttributeList</type> to access the attributes
+            from the element.
+
+    */
+    void startFastElement( ::sal_Int32 Element, FastAttributeList const * pAttrList = nullptr );
+
+    /** receives notification of the end of a known element.
+        @see startFastElement
+     */
+    void endFastElement( ::sal_Int32 Element );
+
+    /** receives notification of the beginning of a single element.
+
+        @param Element
+            contains the integer token from the <type>XFastTokenHandler</type>
+            registered at the <type>XFastParser</type>.<br>
+
+            If the element has a namespace that was registered with the
+            <type>XFastParser</type>, <param>Element</param> contains the integer
+            token of the elements local name from the <type>XFastTokenHandler</type>
+            and the integer token of the namespace combined with an arithmetic
+            <b>or</b> operation.
+
+        @param pAttrList
+            Contains a <type>FastAttributeList</type> to access the attributes
+            from the element.
+
+    */
+    void singleFastElement( ::sal_Int32 Element, FastAttributeList const * pAttrList = nullptr );
+
+    // C++ helpers
+    void writeId( ::sal_Int32 Element );
+    OString getId( ::sal_Int32 Element );
+
+    void write( double value );
+    void write( const OUString& s, bool bEscape = false );
+    void write( const OString& s, bool bEscape = false );
+    void write( const char* pStr, sal_Int32 nLen, bool bEscape = false );
+
+public:
+    /** From now on, don't write directly to the stream, but to top of a stack.
+
+        This is to be able to change the order of the data being written.
+        If you need to write eg.
+          p, r, rPr, [something], /rPr, t, [text], /t, /r, /p,
+        but get it in order
+          p, r, t, [text], /t, rPr, [something], /rPr, /r, /p,
+        simply do
+          p, r, mark(), t, [text], /t, mark(), rPr, [something], /rPr,
+          mergeTopMarks( MergeMarks::PREPEND ), mergeTopMarks( MergeMarks::APPEND ), /r, /p
+        and you are done.
+
+        @param nTag debugging aid to ensure mark and merge match in LIFO order
+     */
+    void mark(sal_Int32 nTag, const Int32Sequence& rOrder);
+
+    /** Merge 2 topmost marks.
+
+        The possibilities: prepend the top before the second top-most
+        mark, append it, append it later or ignore; prepending brings the possibility
+        to switch parts of the output, appending later allows to write some
+        output in advance.
+
+        Writes the result to the output stream if the mark stack becomes empty
+        by the operation.
+
+        When the MergeMarks::POSTPONE is specified, the merge happens just
+        before the next merge.
+
+        @param nTag debugging aid to ensure mark and merge match in LIFO order
+
+        @see mark()
+     */
+    void mergeTopMarks(sal_Int32 nTag,
+        sax_fastparser::MergeMarks eMergeType);
+
+private:
+    /** Helper class to cache data and write in chunks to XOutputStream or ForMerge::append.
+     *  Its flush method needs to be called before touching maMarkStack
+     *  to ensure correct order of ForSort methods.
+     */
+    CachedOutputStream maCachedOutputStream;
+    css::uno::Reference< css::xml::sax::XFastTokenHandler > mxFastTokenHandler;
+
+    class ForMerge : public ForMergeBase
+    {
+        Int8Sequence maData;
+        Int8Sequence maPostponed;
+
+    public:
+        sal_Int32 const m_Tag;
+#ifdef DBG_UTIL
+        // pending close tags, followed by pending open tags
+        std::deque<sal_Int32> m_DebugEndedElements;
+        std::deque<sal_Int32> m_DebugStartedElements;
+        // ... and another buffer for maPostponed ...
+        std::deque<sal_Int32> m_DebugPostponedEndedElements;
+        std::deque<sal_Int32> m_DebugPostponedStartedElements;
+#endif
+
+        explicit ForMerge(sal_Int32 const nTag) : m_Tag(nTag) {}
+
+        virtual void setCurrentElement( ::sal_Int32 /*nToken*/ ) {}
+        virtual Int8Sequence& getData();
+#if OSL_DEBUG_LEVEL > 0
+        virtual void print();
+#endif
+
+        virtual void prepend( const Int8Sequence &rWhat );
+        virtual void append( const css::uno::Sequence<sal_Int8> &rWhat ) override;
+        void postpone( const Int8Sequence &rWhat );
+
+    protected:
+        void resetData( );
+        static void merge( Int8Sequence &rTop, const Int8Sequence &rMerge, bool bAppend );
+    };
+
+    class ForSort : public ForMerge
+    {
+        std::map< ::sal_Int32, Int8Sequence > maData;
+        sal_Int32 mnCurrentElement;
+
+        Int32Sequence maOrder;
+
+    public:
+        ForSort(sal_Int32 const nTag, const Int32Sequence& rOrder)
+            : ForMerge(nTag)
+            , mnCurrentElement( 0 )
+            , maOrder( rOrder )
+        {}
+
+        void setCurrentElement( ::sal_Int32 nToken ) override;
+
+        virtual Int8Sequence& getData() override;
+
+#if OSL_DEBUG_LEVEL > 0
+        virtual void print() override;
+#endif
+
+        virtual void prepend( const Int8Sequence &rWhat ) override;
+        virtual void append( const css::uno::Sequence<sal_Int8> &rWhat ) override;
+    private:
+        void sort();
+    };
+
+    std::stack< std::shared_ptr< ForMerge > > maMarkStack;
+    bool mbMarkStackEmpty;
+    // Would be better to use OStringBuffer instead of these two
+    // but then we couldn't get the rtl_String* member :-(
+    rtl_String *mpDoubleStr;
+    sal_Int32 mnDoubleStrCapacity;
+    TokenValueList maTokenValues;
+    bool mbXescape;     ///< whether to escape invalid XML characters as _xHHHH_ in write(const char*,sal_Int32,true)
+                        /* TODO: make that configurable from the outside for
+                         * some specific cases? */
+
+#ifdef DBG_UTIL
+    std::stack<sal_Int32> m_DebugStartedElements;
+#endif
+
+    void writeTokenValueList();
+    void writeFastAttributeList(FastAttributeList const & rAttrList);
+
+    /** Forward the call to the output stream, or write to the stack.
+
+        The latter in the case that we are inside a mark().
+     */
+    void writeBytes( const css::uno::Sequence< ::sal_Int8 >& aData );
+    void writeBytes( const char* pStr, size_t nLen );
+};
+
+} // namespace sax_fastparser
+
+#endif
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
diff --git a/sax/source/tools/fshelper.cxx b/sax/source/tools/fshelper.cxx
new file mode 100644
index 000000000..41857c95e
--- /dev/null
+++ b/sax/source/tools/fshelper.cxx
@@ -0,0 +1,158 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <sax/fshelper.hxx>
+#include "fastserializer.hxx"
+#include <com/sun/star/xml/sax/XFastTokenHandler.hpp>
+
+using namespace ::com::sun::star;
+using namespace ::com::sun::star::uno;
+
+namespace sax_fastparser {
+
+FastSerializerHelper::FastSerializerHelper(const Reference< io::XOutputStream >& xOutputStream, bool bWriteHeader ) :
+    mpSerializer(new FastSaxSerializer(xOutputStream))
+{
+    if( bWriteHeader )
+        mpSerializer->startDocument();
+}
+
+FastSerializerHelper::~FastSerializerHelper()
+{
+    mpSerializer->endDocument();
+    delete mpSerializer;
+}
+
+void FastSerializerHelper::startElement(sal_Int32 elementTokenId)
+{
+    mpSerializer->startFastElement(elementTokenId);
+}
+void FastSerializerHelper::pushAttributeValue(sal_Int32 attribute, const char* value)
+{
+    mpSerializer->getTokenValueList().emplace_back(attribute, value);
+}
+void FastSerializerHelper::pushAttributeValue(sal_Int32 attribute, const OString& value)
+{
+    mpSerializer->getTokenValueList().emplace_back(attribute, value.getStr());
+}
+void FastSerializerHelper::singleElement(sal_Int32 elementTokenId)
+{
+    mpSerializer->singleFastElement(elementTokenId);
+}
+
+void FastSerializerHelper::endElement(sal_Int32 elementTokenId)
+{
+    mpSerializer->endFastElement(elementTokenId);
+}
+
+void FastSerializerHelper::startElement(sal_Int32 elementTokenId, const XFastAttributeListRef& xAttrList)
+{
+    FastAttributeList* pAttrList = dynamic_cast< FastAttributeList* >(xAttrList.get());
+    assert(pAttrList);
+    mpSerializer->startFastElement(elementTokenId, pAttrList);
+}
+
+void FastSerializerHelper::singleElement(sal_Int32 elementTokenId, const XFastAttributeListRef& xAttrList)
+{
+    FastAttributeList* pAttrList = dynamic_cast< FastAttributeList* >(xAttrList.get());
+    assert(pAttrList);
+    mpSerializer->singleFastElement(elementTokenId, pAttrList);
+}
+
+FastSerializerHelper* FastSerializerHelper::write(const char* value)
+{
+    mpSerializer->write(value, -1);
+    return this;
+}
+
+FastSerializerHelper* FastSerializerHelper::write(const OString& value)
+{
+    mpSerializer->write(value);
+    return this;
+}
+
+FastSerializerHelper* FastSerializerHelper::write(const OUString& value)
+{
+    mpSerializer->write(value);
+    return this;
+}
+
+FastSerializerHelper* FastSerializerHelper::write(sal_Int32 value)
+{
+    mpSerializer->write(OString::number(value));
+    return this;
+}
+
+FastSerializerHelper* FastSerializerHelper::write(sal_Int64 value)
+{
+    mpSerializer->write(OString::number(value));
+    return this;
+}
+
+FastSerializerHelper* FastSerializerHelper::write(double value)
+{
+    mpSerializer->write(value);
+    return this;
+}
+
+FastSerializerHelper* FastSerializerHelper::writeEscaped(const char* value)
+{
+    mpSerializer->write(value, -1, true);
+    return this;
+}
+
+FastSerializerHelper* FastSerializerHelper::writeEscaped(const OUString& value)
+{
+    if (!value.isEmpty())
+        mpSerializer->write(value, true);
+    return this;
+}
+
+FastSerializerHelper* FastSerializerHelper::writeId(sal_Int32 tokenId)
+{
+    mpSerializer->writeId(tokenId);
+    return this;
+}
+
+css::uno::Reference< css::io::XOutputStream > const & FastSerializerHelper::getOutputStream() const
+{
+    return mpSerializer->getOutputStream();
+}
+
+void FastSerializerHelper::mark(
+        sal_Int32 const nTag, const Sequence<sal_Int32>& rOrder)
+{
+    mpSerializer->mark(nTag, rOrder);
+}
+
+void FastSerializerHelper::mergeTopMarks(
+        sal_Int32 const nTag, MergeMarks const eMergeType)
+{
+    mpSerializer->mergeTopMarks(nTag, eMergeType);
+}
+
+FastAttributeList * FastSerializerHelper::createAttrList()
+{
+    return new FastAttributeList( nullptr );
+}
+
+
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */