Adding upstream version 4:7.4.7.upstream/4%7.4.7upstream

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

1 files changed, 318 insertions, 0 deletions

diff --git a/vcl/source/gdi/pdfobjectcopier.cxx b/vcl/source/gdi/pdfobjectcopier.cxx
new file mode 100644
index 000000000..93b7b4989
--- /dev/null
+++ b/vcl/source/gdi/pdfobjectcopier.cxx
@@ -0,0 +1,318 @@
+/* -*- 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/.
+ */
+
+#include <sal/log.hxx>
+#include <sal/types.h>
+#include <rtl/strbuf.hxx>
+#include <tools/stream.hxx>
+#include <tools/zcodec.hxx>
+
+#include <vcl/filter/pdfdocument.hxx>
+#include <vcl/filter/pdfobjectcontainer.hxx>
+
+#include <pdf/objectcopier.hxx>
+#include <pdf/pdfwriter_impl.hxx>
+
+namespace vcl
+{
+PDFObjectCopier::PDFObjectCopier(PDFObjectContainer& rContainer)
+    : m_rContainer(rContainer)
+{
+}
+
+void PDFObjectCopier::copyRecursively(OStringBuffer& rLine, filter::PDFElement& rInputElement,
+                                      SvMemoryStream& rDocBuffer,
+                                      std::map<sal_Int32, sal_Int32>& rCopiedResources)
+{
+    if (auto pReference = dynamic_cast<filter::PDFReferenceElement*>(&rInputElement))
+    {
+        filter::PDFObjectElement* pReferenced = pReference->LookupObject();
+        if (pReferenced)
+        {
+            // Copy the referenced object.
+            sal_Int32 nRef = copyExternalResource(rDocBuffer, *pReferenced, rCopiedResources);
+
+            // Write the updated reference.
+            rLine.append(nRef);
+            rLine.append(" 0 R");
+        }
+    }
+    else if (auto pInputArray = dynamic_cast<filter::PDFArrayElement*>(&rInputElement))
+    {
+        rLine.append("[ ");
+        for (auto const& pElement : pInputArray->GetElements())
+        {
+            copyRecursively(rLine, *pElement, rDocBuffer, rCopiedResources);
+            rLine.append(" ");
+        }
+        rLine.append("] ");
+    }
+    else if (auto pInputDictionary = dynamic_cast<filter::PDFDictionaryElement*>(&rInputElement))
+    {
+        rLine.append("<< ");
+        for (auto const& pPair : pInputDictionary->GetItems())
+        {
+            rLine.append("/");
+            rLine.append(pPair.first);
+            rLine.append(" ");
+            copyRecursively(rLine, *pPair.second, rDocBuffer, rCopiedResources);
+            rLine.append(" ");
+        }
+        rLine.append(">> ");
+    }
+    else
+    {
+        rInputElement.writeString(rLine);
+    }
+}
+
+sal_Int32 PDFObjectCopier::copyExternalResource(SvMemoryStream& rDocBuffer,
+                                                filter::PDFObjectElement& rObject,
+                                                std::map<sal_Int32, sal_Int32>& rCopiedResources)
+{
+    auto it = rCopiedResources.find(rObject.GetObjectValue());
+    if (it != rCopiedResources.end())
+    {
+        // This resource was already copied once, nothing to do.
+        return it->second;
+    }
+
+    sal_Int32 nObject = m_rContainer.createObject();
+    // Remember what is the ID of this object in our output.
+    rCopiedResources[rObject.GetObjectValue()] = nObject;
+    SAL_INFO("vcl.pdfwriter", "PDFObjectCopier::copyExternalResource: " << rObject.GetObjectValue()
+                                                                        << " -> " << nObject);
+
+    OStringBuffer aLine;
+    aLine.append(nObject);
+    aLine.append(" 0 obj\n");
+
+    if (rObject.GetDictionary())
+    {
+        aLine.append("<< ");
+        bool bFirst = true;
+        for (auto const& rPair : rObject.GetDictionaryItems())
+        {
+            if (bFirst)
+                bFirst = false;
+            else
+                aLine.append(" ");
+
+            aLine.append("/");
+            aLine.append(rPair.first);
+            aLine.append(" ");
+            copyRecursively(aLine, *rPair.second, rDocBuffer, rCopiedResources);
+        }
+
+        aLine.append(" >>\n");
+    }
+
+    filter::PDFStreamElement* pStream = rObject.GetStream();
+    if (pStream)
+    {
+        aLine.append("stream\n");
+    }
+
+    if (filter::PDFArrayElement* pArray = rObject.GetArray())
+    {
+        aLine.append("[ ");
+
+        const std::vector<filter::PDFElement*>& rElements = pArray->GetElements();
+
+        bool bFirst = true;
+        for (auto const& pElement : rElements)
+        {
+            if (bFirst)
+                bFirst = false;
+            else
+                aLine.append(" ");
+            copyRecursively(aLine, *pElement, rDocBuffer, rCopiedResources);
+        }
+        aLine.append("]\n");
+    }
+
+    // If the object has a number element outside a dictionary or array, copy that.
+    if (filter::PDFNumberElement* pNumber = rObject.GetNumberElement())
+    {
+        pNumber->writeString(aLine);
+        aLine.append("\n");
+    }
+
+    // We have the whole object, now write it to the output.
+    if (!m_rContainer.updateObject(nObject))
+        return -1;
+    if (!m_rContainer.writeBuffer(aLine.getStr(), aLine.getLength()))
+        return -1;
+    aLine.setLength(0);
+
+    if (pStream)
+    {
+        SvMemoryStream& rStream = pStream->GetMemory();
+        m_rContainer.checkAndEnableStreamEncryption(nObject);
+        aLine.append(static_cast<const char*>(rStream.GetData()), rStream.GetSize());
+        if (!m_rContainer.writeBuffer(aLine.getStr(), aLine.getLength()))
+            return -1;
+        aLine.setLength(0);
+        m_rContainer.disableStreamEncryption();
+
+        aLine.append("\nendstream\n");
+        if (!m_rContainer.writeBuffer(aLine.getStr(), aLine.getLength()))
+            return -1;
+        aLine.setLength(0);
+    }
+
+    aLine.append("endobj\n\n");
+    if (!m_rContainer.writeBuffer(aLine.getStr(), aLine.getLength()))
+        return -1;
+
+    return nObject;
+}
+
+OString PDFObjectCopier::copyExternalResources(filter::PDFObjectElement& rPage,
+                                               const OString& rKind,
+                                               std::map<sal_Int32, sal_Int32>& rCopiedResources)
+{
+    // A name - object ID map, IDs as they appear in our output, not the
+    // original ones.
+    std::map<OString, sal_Int32> aRet;
+
+    // Get the rKind subset of the resource dictionary.
+    std::map<OString, filter::PDFElement*> aItems;
+    if (auto pResources = dynamic_cast<filter::PDFDictionaryElement*>(rPage.Lookup("Resources")))
+    {
+        // Resources is a direct dictionary.
+        filter::PDFElement* pLookup = pResources->LookupElement(rKind);
+        if (auto pDictionary = dynamic_cast<filter::PDFDictionaryElement*>(pLookup))
+        {
+            // rKind is an inline dictionary.
+            aItems = pDictionary->GetItems();
+        }
+        else if (auto pReference = dynamic_cast<filter::PDFReferenceElement*>(pLookup))
+        {
+            // rKind refers to a dictionary.
+            filter::PDFObjectElement* pReferenced = pReference->LookupObject();
+            if (!pReferenced)
+            {
+                return {};
+            }
+
+            aItems = pReferenced->GetDictionaryItems();
+        }
+    }
+    else if (filter::PDFObjectElement* pPageResources = rPage.LookupObject("Resources"))
+    {
+        // Resources is an indirect object.
+        filter::PDFElement* pValue = pPageResources->Lookup(rKind);
+        if (auto pDictionary = dynamic_cast<filter::PDFDictionaryElement*>(pValue))
+            // Kind is a direct dictionary.
+            aItems = pDictionary->GetItems();
+        else if (filter::PDFObjectElement* pObject = pPageResources->LookupObject(rKind))
+            // Kind is an indirect object.
+            aItems = pObject->GetDictionaryItems();
+    }
+    if (aItems.empty())
+        return {};
+
+    SvMemoryStream& rDocBuffer = rPage.GetDocument().GetEditBuffer();
+
+    for (const auto& rItem : aItems)
+    {
+        // For each item copy it over to our output then insert it into aRet.
+        auto pReference = dynamic_cast<filter::PDFReferenceElement*>(rItem.second);
+        if (!pReference)
+            continue;
+
+        filter::PDFObjectElement* pValue = pReference->LookupObject();
+        if (!pValue)
+            continue;
+
+        // Then copying over an object copy its dictionary and its stream.
+        sal_Int32 nObject = copyExternalResource(rDocBuffer, *pValue, rCopiedResources);
+        aRet[rItem.first] = nObject;
+    }
+
+    // Build the dictionary entry string.
+    OStringBuffer sRet("/" + rKind + "<<");
+    for (const auto& rPair : aRet)
+    {
+        sRet.append("/" + rPair.first + " " + OString::number(rPair.second) + " 0 R");
+    }
+    sRet.append(">>");
+
+    return sRet.makeStringAndClear();
+}
+
+void PDFObjectCopier::copyPageResources(filter::PDFObjectElement* pPage, OStringBuffer& rLine)
+{
+    // Maps from source object id (PDF image) to target object id (export result).
+    std::map<sal_Int32, sal_Int32> aCopiedResources;
+    copyPageResources(pPage, rLine, aCopiedResources);
+}
+
+void PDFObjectCopier::copyPageResources(filter::PDFObjectElement* pPage, OStringBuffer& rLine,
+                                        std::map<sal_Int32, sal_Int32>& rCopiedResources)
+{
+    rLine.append(" /Resources <<");
+    static const std::initializer_list<OString> aKeys
+        = { "ColorSpace", "ExtGState", "Font", "XObject", "Shading" };
+    for (const auto& rKey : aKeys)
+    {
+        rLine.append(copyExternalResources(*pPage, rKey, rCopiedResources));
+    }
+    rLine.append(">>");
+}
+
+sal_Int32 PDFObjectCopier::copyPageStreams(std::vector<filter::PDFObjectElement*>& rContentStreams,
+                                           SvMemoryStream& rStream, bool& rCompressed)
+{
+    for (auto pContent : rContentStreams)
+    {
+        filter::PDFStreamElement* pPageStream = pContent->GetStream();
+        if (!pPageStream)
+        {
+            SAL_WARN("vcl.pdfwriter", "PDFObjectCopier::copyPageStreams: contents has no stream");
+            continue;
+        }
+
+        SvMemoryStream& rPageStream = pPageStream->GetMemory();
+
+        auto pFilter = dynamic_cast<filter::PDFNameElement*>(pContent->Lookup("Filter"));
+        if (pFilter)
+        {
+            if (pFilter->GetValue() != "FlateDecode")
+            {
+                continue;
+            }
+
+            SvMemoryStream aMemoryStream;
+            ZCodec aZCodec;
+            rPageStream.Seek(0);
+            aZCodec.BeginCompression();
+            aZCodec.Decompress(rPageStream, aMemoryStream);
+            if (!aZCodec.EndCompression())
+            {
+                SAL_WARN("vcl.pdfwriter", "PDFObjectCopier::copyPageStreams: decompression failed");
+                continue;
+            }
+
+            rStream.WriteBytes(aMemoryStream.GetData(), aMemoryStream.GetSize());
+        }
+        else
+        {
+            rStream.WriteBytes(rPageStream.GetData(), rPageStream.GetSize());
+        }
+    }
+
+    rCompressed = PDFWriterImpl::compressStream(&rStream);
+
+    return rStream.Tell();
+}
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */