reworked solution for i#118012 crash during deletion of rows

commit 16155fdc introduced a bottleneck
in area broadcasts with the change from
http://svn.apache.org/viewvc?view=revision&revision=1297916

That for each broadcast copied all areas in the affected slot(s) before
broadcasting, just in case that during Notify() an area would be removed
from the same slot invalidating the iterator, and attempted to find the
area again in the original set. For documents with lots of areas in a
slot and/or lots of slots that would be a major performance penalty.

Reworked such that to-be-erased area entries are marked and remembered
instead and cleaned up after iteration.

Change-Id: Ia485941746f435f8410d2084868263e84f25ffcb

sc/source/core/inc/bcaslot.hxx

@@ -71,23 +71,31 @@ inline bool ScBroadcastArea::operator==( const ScBroadcastArea & rArea ) const
 
 //=============================================================================
 
+struct ScBroadcastAreaEntry
+{
+    ScBroadcastArea* mpArea;
+    mutable bool     mbErasure;     ///< TRUE if marked for erasure in this set
+
+    ScBroadcastAreaEntry( ScBroadcastArea* p ) : mpArea( p), mbErasure( false) {}
+};
+
 struct ScBroadcastAreaHash
 {
-    size_t operator()( const ScBroadcastArea* p ) const
+    size_t operator()( const ScBroadcastAreaEntry& rEntry ) const
     {
-        return p->GetRange().hashArea();
+        return rEntry.mpArea->GetRange().hashArea();
     }
 };
 
 struct ScBroadcastAreaEqual
 {
-    bool operator()( const ScBroadcastArea* p1, const ScBroadcastArea* p2) const
+    bool operator()( const ScBroadcastAreaEntry& rEntry1, const ScBroadcastAreaEntry& rEntry2) const
     {
-        return *p1 == *p2;
+        return *rEntry1.mpArea == *rEntry2.mpArea;
     }
 };
 
-typedef ::boost::unordered_set< ScBroadcastArea*, ScBroadcastAreaHash, ScBroadcastAreaEqual > ScBroadcastAreas;
+typedef ::boost::unordered_set< ScBroadcastAreaEntry, ScBroadcastAreaHash, ScBroadcastAreaEqual > ScBroadcastAreas;
 
 //=============================================================================
 
@@ -122,6 +130,7 @@ private:
     mutable ScBroadcastArea aTmpSeekBroadcastArea;      // for FindBroadcastArea()
     ScDocument*         pDoc;
     ScBroadcastAreaSlotMachine* pBASM;
+    bool                mbInBroadcastIteration;
 
     ScBroadcastAreas::iterator  FindBroadcastArea( const ScRange& rRange ) const;
 
@@ -135,6 +144,14 @@ private:
       */
     bool                CheckHardRecalcStateCondition() const;
 
+    /** Finally erase all areas pushed as to-be-erased. */
+    void                FinallyEraseAreas();
+
+    bool                isMarkedErased( const ScBroadcastAreas::iterator& rIter )
+                            {
+                                return (*rIter).mbErasure;
+                            }
+
 public:
                         ScBroadcastAreaSlot( ScDocument* pDoc,
                                         ScBroadcastAreaSlotMachine* pBASM );
@@ -172,16 +189,27 @@ public:
     void                EndListeningArea( const ScRange& rRange,
                                             SvtListener* pListener,
                                             ScBroadcastArea*& rpArea );
-    sal_Bool                AreaBroadcast( const ScHint& rHint ) const;
+    sal_Bool                AreaBroadcast( const ScHint& rHint );
     /// @return sal_True if at least one broadcast occurred.
     sal_Bool                AreaBroadcastInRange( const ScRange& rRange,
-                                              const ScHint& rHint ) const;
+                                              const ScHint& rHint );
     void                DelBroadcastAreasInRange( const ScRange& rRange );
     void                UpdateRemove( UpdateRefMode eUpdateRefMode,
                                         const ScRange& rRange,
                                         SCsCOL nDx, SCsROW nDy, SCsTAB nDz );
     void                UpdateRemoveArea( ScBroadcastArea* pArea );
     void                UpdateInsert( ScBroadcastArea* pArea );
+
+
+    bool                IsInBroadcastIteration() const { return mbInBroadcastIteration; }
+
+    /** Erase an area from set and delete it if last reference, or if
+        mbInBroadcastIteration is set push it to the vector of to-be-erased
+        areas instead.
+
+        Meant to be used internally and from ScBroadcastAreaSlotMachine only.
+     */
+    void                EraseArea( ScBroadcastAreas::iterator& rIter );
 };
 
 
@@ -229,14 +257,17 @@ private:
 
     typedef ::std::map< SCTAB, TableSlots* > TableSlotsMap;
 
+    typedef ::std::vector< ::std::pair< ScBroadcastAreaSlot*, ScBroadcastAreas::iterator > > AreasToBeErased;
+
 private:
     ScBroadcastAreasBulk  aBulkBroadcastAreas;
     TableSlotsMap         aTableSlotsMap;
+    AreasToBeErased       maAreasToBeErased;
     SvtBroadcaster       *pBCAlways;             // for the RC_ALWAYS special range
     ScDocument           *pDoc;
     ScBroadcastArea      *pUpdateChain;
     ScBroadcastArea      *pEOUpdateChain;
-    sal_uLong                 nInBulkBroadcast;
+    sal_uLong             nInBulkBroadcast;
 
     inline SCSIZE       ComputeSlotOffset( const ScAddress& rAddress ) const;
     void                ComputeAreaPoints( const ScRange& rRange,
@@ -267,6 +298,12 @@ public:
     inline ScBroadcastArea* GetEOUpdateChain() const { return pEOUpdateChain; }
     inline void SetEOUpdateChain( ScBroadcastArea* p ) { pEOUpdateChain = p; }
     inline bool IsInBulkBroadcast() const { return nInBulkBroadcast > 0; }
+
+    // only for ScBroadcastAreaSlot
+    void                PushAreaToBeErased( ScBroadcastAreaSlot* pSlot,
+                                            ScBroadcastAreas::iterator& rIter );
+    // only for ScBroadcastAreaSlot
+    void                FinallyEraseAreas( ScBroadcastAreaSlot* pSlot );
 };