unoxml/source/dom/elementlist.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #include "elementlist.hxx"
  21
  22 #include <string.h>
  23 #include <string_view>
  24
  25 #include <cppuhelper/implbase.hxx>
  26 #include <o3tl/safeint.hxx>
  27 #include <utility>
  28 #include <comphelper/diagnose_ex.hxx>
  29
  30 #include "element.hxx"
  31 #include "document.hxx"
  32
  33 using namespace css::uno;
  34 using namespace css::xml::dom;
  35 using namespace css::xml::dom::events;
  36
  37 namespace
  38 {
  39     class WeakEventListener : public ::cppu::WeakImplHelper<css::xml::dom::events::XEventListener>
  40     {
  41     private:
  42         css::uno::WeakReference<css::xml::dom::events::XEventListener> mxOwner;
  43
  44     public:
  45         explicit WeakEventListener(const css::uno::Reference<css::xml::dom::events::XEventListener>& rOwner)
  46             : mxOwner(rOwner)
  47         {
  48         }
  49
  50         virtual void SAL_CALL handleEvent(const css::uno::Reference<css::xml::dom::events::XEvent>& rEvent) override
  51         {
  52             css::uno::Reference<css::xml::dom::events::XEventListener> xOwner(mxOwner.get(),
  53                 css::uno::UNO_QUERY);
  54             if (xOwner.is())
  55                 xOwner->handleEvent(rEvent);
  56         }
  57     };
  58 }
  59
  60 namespace DOM
  61 {
  62
  63     static xmlChar* lcl_initXmlString(std::u16string_view rString)
  64     {
  65         OString const os =
  66             OUStringToOString(rString, RTL_TEXTENCODING_UTF8);
  67         xmlChar *const pRet = new xmlChar[os.getLength() + 1];
  68         strcpy(reinterpret_cast<char*>(pRet), os.getStr());
  69         return pRet;
  70     }
  71
  72     CElementList::CElementList(::rtl::Reference<CElement> const& pElement,
  73             ::osl::Mutex & rMutex,
  74             std::u16string_view rName, OUString const*const pURI)
  75         : m_xImpl(new CElementListImpl(pElement, rMutex, rName, pURI))
  76     {
  77         if (pElement.is()) {
  78             m_xImpl->registerListener(*pElement);
  79         }
  80     }
  81
  82     CElementListImpl::CElementListImpl(::rtl::Reference<CElement> pElement,
  83             ::osl::Mutex & rMutex,
  84             std::u16string_view rName, OUString const*const pURI)
  85         : m_pElement(std::move(pElement))
  86         , m_rMutex(rMutex)
  87         , m_pName(lcl_initXmlString(rName))
  88         , m_pURI(pURI ? lcl_initXmlString(*pURI) : nullptr)
  89         , m_bRebuild(true)
  90     {
  91     }
  92
  93     CElementListImpl::~CElementListImpl()
  94     {
  95         if (m_xEventListener.is() && m_pElement.is())
  96         {
  97             Reference< XEventTarget > xTarget = m_pElement;
  98             assert(xTarget.is());
  99             if (!xTarget.is())
 100                 return;
 101             xTarget->removeEventListener("DOMSubtreeModified", m_xEventListener, false/*capture*/);
 102         }
 103     }
 104
 105     void CElementListImpl::registerListener(CElement & rElement)
 106     {
 107         try {
 108             Reference< XEventTarget > const xTarget(
 109                     static_cast<XElement*>(& rElement), UNO_QUERY_THROW);
 110             m_xEventListener = new WeakEventListener(this);
 111             xTarget->addEventListener("DOMSubtreeModified", m_xEventListener, false/*capture*/);
 112         } catch (const Exception &){
 113             TOOLS_WARN_EXCEPTION( "unoxml", "Exception caught while registering NodeList as listener");
 114         }
 115     }
 116
 117     void CElementListImpl::buildlist(xmlNodePtr pNode, bool start)
 118     {
 119         // bail out if no rebuild is needed
 120         if (start) {
 121             if (!m_bRebuild)
 122             {
 123                 return;
 124             } else {
 125                 m_nodevector.clear();
 126                 m_bRebuild = false; // don't rebuild until tree is mutated
 127             }
 128         }
 129
 130         while (pNode != nullptr )
 131         {
 132             if (pNode->type == XML_ELEMENT_NODE &&
 133                 (strcmp(reinterpret_cast<char const *>(pNode->name), reinterpret_cast<char*>(m_pName.get())) == 0))
 134             {
 135                 if (!m_pURI) {
 136                     m_nodevector.push_back(pNode);
 137                 } else {
 138                     if (pNode->ns != nullptr && (0 ==
 139                          strcmp(reinterpret_cast<char const *>(pNode->ns->href), reinterpret_cast<char*>(m_pURI.get()))))
 140                     {
 141                         m_nodevector.push_back(pNode);
 142                     }
 143                 }
 144             }
 145             if (pNode->children != nullptr) buildlist(pNode->children, false);
 146
 147             if (!start) pNode = pNode->next;
 148             else break; // fold back
 149         }
 150     }
 151
 152     /**
 153     The number of nodes in the list.
 154     */
 155     sal_Int32 SAL_CALL CElementListImpl::getLength()
 156     {
 157         ::osl::MutexGuard const g(m_rMutex);
 158
 159         if (!m_pElement.is()) { return 0; }
 160
 161         // this has to be 'live'
 162         buildlist(m_pElement->GetNodePtr());
 163         return m_nodevector.size();
 164     }
 165     /**
 166     Returns the indexth item in the collection.
 167     */
 168     Reference< XNode > SAL_CALL CElementListImpl::item(sal_Int32 index)
 169     {
 170         if (index < 0) throw RuntimeException();
 171
 172         ::osl::MutexGuard const g(m_rMutex);
 173
 174         if (!m_pElement.is()) { return nullptr; }
 175
 176         buildlist(m_pElement->GetNodePtr());
 177         if (m_nodevector.size() <= o3tl::make_unsigned(index)) {
 178             throw RuntimeException();
 179         }
 180         return m_pElement->GetOwnerDocument().GetCNode(m_nodevector[index]);
 181     }
 182
 183     // tree mutations can change the list
 184     void SAL_CALL CElementListImpl::handleEvent(Reference< XEvent > const&)
 185     {
 186         ::osl::MutexGuard const g(m_rMutex);
 187
 188         m_bRebuild = true;
 189     }
 190 }
 191
 192 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */