forcepoint#76 avoid deleting footnote that would delete undeletable page

Change-Id: I4622569eb9c757c6dcbdda32081ddc94e53db919
Reviewed-on: https://gerrit.libreoffice.org/64622
Tested-by: Jenkins
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>

5 files changed, 34 insertions, 4 deletions

diff --git a/sw/source/core/inc/frame.hxx b/sw/source/core/inc/frame.hxx
index 1d3defae80da..920bd621fff4 100644
--- a/sw/source/core/inc/frame.hxx
+++ b/sw/source/core/inc/frame.hxx
@@ -856,7 +856,7 @@ public:
     bool IsProtected() const;
 
     bool IsColLocked()  const { return mbColLocked; }
-    bool IsDeleteForbidden()  const { return mbForbidDelete; }
+    virtual bool IsDeleteForbidden() const { return mbForbidDelete; }
 
     /// this is the only way to delete a SwFrame instance
     static void DestroyFrame(SwFrame *const pFrame);
diff --git a/sw/source/core/inc/ftnfrm.hxx b/sw/source/core/inc/ftnfrm.hxx
index c0848948848f..b469e4169d78 100644
--- a/sw/source/core/inc/ftnfrm.hxx
+++ b/sw/source/core/inc/ftnfrm.hxx
@@ -80,6 +80,7 @@ class SwFootnoteFrame: public SwLayoutFrame
 public:
     SwFootnoteFrame( SwFrameFormat*, SwFrame*, SwContentFrame*, SwTextFootnote* );
 
+    virtual bool IsDeleteForbidden() const override;
     virtual void Cut() override;
     virtual void Paste( SwFrame* pParent, SwFrame* pSibling = nullptr ) override;
 
diff --git a/sw/source/core/layout/calcmove.cxx b/sw/source/core/layout/calcmove.cxx
index 72d74ed63974..96fa282153dc 100644
--- a/sw/source/core/layout/calcmove.cxx
+++ b/sw/source/core/layout/calcmove.cxx
@@ -242,6 +242,7 @@ void SwFrame::PrepareMake(vcl::RenderContext* pRenderContext)
     StackHack aHack;
     if ( GetUpper() )
     {
+        SwFrameDeleteGuard aDeleteGuard(this);
         if ( lcl_IsCalcUpperAllowed( *this ) )
             GetUpper()->Calc(pRenderContext);
         OSL_ENSURE( GetUpper(), ":-( Layout unstable (Upper gone)." );
diff --git a/sw/source/core/layout/ftnfrm.cxx b/sw/source/core/layout/ftnfrm.cxx
index 7cc0b077e6eb..1290c125427e 100644
--- a/sw/source/core/layout/ftnfrm.cxx
+++ b/sw/source/core/layout/ftnfrm.cxx
@@ -474,6 +474,27 @@ void SwFootnoteFrame::InvalidateNxtFootnoteCnts( SwPageFrame const *pPage )
     }
 }
 
+bool SwFootnoteFrame::IsDeleteForbidden() const
+{
+    if (SwLayoutFrame::IsDeleteForbidden())
+        return true;
+    // needs to be in sync with the ::Cut logic
+    const SwLayoutFrame *pUp = GetUpper();
+    if (pUp)
+    {
+        if (GetPrev())
+            return false;
+
+        // The last footnote takes its container along if it
+        // is deleted. Cut would put pUp->Lower() to the value
+        // of GetNext(), so if there is no GetNext then
+        // Cut would delete pUp. If that condition is true
+        // here then check if the container is delete-forbidden
+        return !GetNext() && pUp->IsDeleteForbidden();
+    }
+    return false;
+}
+
 void SwFootnoteFrame::Cut()
 {
     if ( GetNext() )
@@ -499,7 +520,7 @@ void SwFootnoteFrame::Cut()
     if ( pUp )
     {
         // The last footnote takes its container along
-        if ( !pUp->Lower() )
+        if (!pUp->Lower())
         {
             SwPageFrame *pPage = pUp->FindPageFrame();
             if ( pPage )
@@ -1590,7 +1611,8 @@ void SwFootnoteBossFrame::AppendFootnote( SwContentFrame *pRef, SwTextFootnote *
             pNew->Calc(getRootFrame()->GetCurrShell()->GetOut());
             // #i57914# - adjust fix #i49383#
             if ( !bOldFootnoteFrameLocked && !pNew->GetLower() &&
-                 !pNew->IsColLocked() && !pNew->IsBackMoveLocked() )
+                 !pNew->IsColLocked() && !pNew->IsBackMoveLocked() &&
+                 !pNew->IsDeleteForbidden() )
             {
                 pNew->Cut();
                 SwFrame::DestroyFrame(pNew);
@@ -2199,7 +2221,8 @@ void SwFootnoteBossFrame::RearrangeFootnotes( const SwTwips nDeadLine, const boo
                         if ( !bLock && bUnlockLastFootnoteFrame &&
                              !pLastFootnoteFrame->GetLower() &&
                              !pLastFootnoteFrame->IsColLocked() &&
-                             !pLastFootnoteFrame->IsBackMoveLocked() )
+                             !pLastFootnoteFrame->IsBackMoveLocked() &&
+                             !pLastFootnoteFrame->IsDeleteForbidden() )
                         {
                             pLastFootnoteFrame->Cut();
                             SwFrame::DestroyFrame(pLastFootnoteFrame);
diff --git a/sw/source/core/layout/tabfrm.cxx b/sw/source/core/layout/tabfrm.cxx
index a7c7edf21a2c..16c2664b177c 100644
--- a/sw/source/core/layout/tabfrm.cxx
+++ b/sw/source/core/layout/tabfrm.cxx
@@ -853,6 +853,11 @@ bool SwTabFrame::RemoveFollowFlowLine()
     // #140081# Make code robust.
     if ( !pFollowFlowLine || !pLastLine )
         return true;
+    if (pFollowFlowLine->IsDeleteForbidden())
+    {
+        SAL_WARN("sw.layout", "Cannot remove in-use Follow Flow Line");
+        return true;
+    }
 
     // Move content
     lcl_MoveRowContent( *pFollowFlowLine, *static_cast<SwRowFrame*>(pLastLine) );