xmlsecurity: show PDF signature right after adding it

Also:

- handle PDF in DocumentSignatureManager::write(), so the PDF file is
  not truncated when closing the document signatures dialog, and
- handle PDF in DigitalSignaturesDialog::canAddRemove()

Change-Id: I77c1fcdcbdcb079ce934f37546129d9d280e5d2e

xmlsecurity/source/dialogs/digitalsignaturesdialog.cxx

@@ -244,8 +244,12 @@ void DigitalSignaturesDialog::SetSignatureStream( const css::uno::Reference < cs
 
 bool DigitalSignaturesDialog::canAddRemove()
 {
-    //m56
     bool ret = true;
+
+    if (!maSignatureManager.mxStore.is())
+        // It's always possible to append a PDF signature.
+        return ret;
+
     OSL_ASSERT(maSignatureManager.mxStore.is());
     bool bDoc1_1 = DocumentSignatureHelper::isODFPre_1_2(m_sODFVersion);
     SaveODFItem item;
@@ -357,7 +361,11 @@ IMPL_LINK_NOARG(DigitalSignaturesDialog, AddButtonHdl, Button*, void)
                 return;
             mbSignaturesChanged = true;
 
-            sal_Int32 nStatus = maSignatureManager.maSignatureHelper.GetSignatureInformation( nSecurityId ).nStatus;
+            sal_Int32 nStatus = xml::crypto::SecurityOperationStatus_OPERATION_SUCCEEDED;
+
+            if (maSignatureManager.mxStore.is())
+                // In the PDF case the signature information is only available after parsing.
+                nStatus = maSignatureManager.maSignatureHelper.GetSignatureInformation( nSecurityId ).nStatus;
 
             if ( nStatus == css::xml::crypto::SecurityOperationStatus_OPERATION_SUCCEEDED )
             {

xmlsecurity/source/helper/documentsignaturemanager.cxx

@@ -385,6 +385,12 @@ void DocumentSignatureManager::read(bool bUseTempStream, bool bCacheLastSignatur
 
 void DocumentSignatureManager::write()
 {
+    if (!mxStore.is())
+    {
+        // Something not ZIP based, assume PDF, which is written directly in add() already.
+        return;
+    }
+
     // Export all other signatures...
     SignatureStreamHelper aStreamHelper = ImplOpenSignatureStream(embed::ElementModes::WRITE|embed::ElementModes::TRUNCATE, false);