sd signature line: teach PDFDocument how to use PDFObjectCopier

This will allow using the object copier in
PDFDocument::WriteAppearanceObject(), so we can include the signature
line pdf export result in a pdf signature of the original pdf.

Change-Id: Iabc508081c5820f4ca997a2d264de9bdb06f82bd
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/96607
Reviewed-by: Miklos Vajna <vmiklos@collabora.com>
Tested-by: Jenkins

1 files changed, 31 insertions, 0 deletions

diff --git a/vcl/source/filter/ipdf/pdfdocument.cxx b/vcl/source/filter/ipdf/pdfdocument.cxx
index ca6d8aa6e486..09439604996d 100644
--- a/vcl/source/filter/ipdf/pdfdocument.cxx
+++ b/vcl/source/filter/ipdf/pdfdocument.cxx
@@ -26,6 +26,7 @@
 #include <svl/cryptosign.hxx>
 #include <tools/zcodec.hxx>
 #include <vcl/pdfwriter.hxx>
+#include <o3tl/safeint.hxx>
 
 using namespace com::sun::star;
 
@@ -126,6 +127,8 @@ XRefEntry::XRefEntry() = default;
 
 PDFDocument::PDFDocument() = default;
 
+PDFDocument::~PDFDocument() = default;
+
 bool PDFDocument::RemoveSignature(size_t nPosition)
 {
     std::vector<PDFObjectElement*> aSignatures = GetSignatureWidgets();
@@ -151,6 +154,34 @@ bool PDFDocument::RemoveSignature(size_t nPosition)
     return m_aEditBuffer.good();
 }
 
+sal_Int32 PDFDocument::createObject()
+{
+    sal_Int32 nObject = m_aXRef.size();
+    m_aXRef[nObject] = XRefEntry();
+    return nObject;
+}
+
+bool PDFDocument::updateObject(sal_Int32 nObject)
+{
+    if (o3tl::make_unsigned(nObject) >= m_aXRef.size())
+    {
+        SAL_WARN("vcl.filter", "PDFDocument::updateObject: invalid nObject");
+        return false;
+    }
+
+    XRefEntry aEntry;
+    aEntry.SetOffset(m_aEditBuffer.Tell());
+    aEntry.SetDirty(true);
+    m_aXRef[nObject] = aEntry;
+    return true;
+}
+
+bool PDFDocument::writeBuffer(const void* pBuffer, sal_uInt64 nBytes)
+{
+    std::size_t nWritten = m_aEditBuffer.WriteBytes(pBuffer, nBytes);
+    return nWritten == nBytes;
+}
+
 void PDFDocument::SetSignatureLine(const std::vector<sal_Int8>& rSignatureLine)
 {
     m_aSignatureLine = rSignatureLine;