make VLOOKUP in Calc thread-safe

There is mutex protection needed for accessing the same SvtBroadcaster
when calling StartListeningArea(). Also some of the memory management
and caching needed fixing.

Change-Id: Ia57ed85286cf195521719cfd3b320f73a6342bb1
Reviewed-on: https://gerrit.libreoffice.org/61187
Tested-by: Jenkins
Reviewed-by: Luboš Luňák <l.lunak@collabora.com>

3 files changed, 22 insertions, 13 deletions

diff --git a/sc/inc/document.hxx b/sc/inc/document.hxx
index 06c155a07aa4..96b28d4d13f0 100644
--- a/sc/inc/document.hxx
+++ b/sc/inc/document.hxx
@@ -171,7 +171,7 @@ class VirtualDevice;
 class ScAutoNameCache;
 class ScTemporaryChartLock;
 class ScLookupCache;
-struct ScLookupCacheMapImpl;
+struct ScLookupCacheMap;
 class SfxUndoManager;
 class ScFormulaParserPool;
 struct ScClipParam;
@@ -276,11 +276,8 @@ struct ScDocumentThreadSpecific
 {
     ScRecursionHelper*      pRecursionHelper;               // information for recursive and iterative cell formulas
 
-    ScLookupCacheMapImpl*   pLookupCacheMapImpl;            // cache for lookups like VLOOKUP and MATCH
-
     ScDocumentThreadSpecific() :
-        pRecursionHelper(nullptr),
-        pLookupCacheMapImpl(nullptr)
+        pRecursionHelper(nullptr)
     {
     }
 
@@ -457,6 +454,9 @@ private:
 
     mutable ScInterpreterContext maInterpreterContext;
 
+    osl::Mutex mScLookupMutex; // protection for thread-unsafe parts of handling ScLookup
+    std::vector<ScLookupCacheMap*> mThreadStoredScLookupCaches; // temporarily stored for computation threads
+
     sal_uInt16              nSrcVer;                        // file version (load/save)
     sal_uInt16              nFormulaTrackCount;
     HardRecalcState         eHardRecalcState;               // off, temporary, eternal
@@ -582,7 +582,8 @@ public:
         maInterpreterContext.mpFormatter = GetFormatTable();
         return maInterpreterContext;
     }
-    void MergeBackIntoNonThreadedContext( ScInterpreterContext& threadedContext );
+    void SetupFromNonThreadedContext( ScInterpreterContext& threadedContext, int threadNumber );
+    void MergeBackIntoNonThreadedContext( ScInterpreterContext& threadedContext, int threadNumber );
     void SetThreadedGroupCalcInProgress( bool set ) { (void)this; ScGlobal::bThreadedGroupCalcInProgress = set; }
     bool IsThreadedGroupCalcInProgress() const { (void)this; return ScGlobal::bThreadedGroupCalcInProgress; }
 
@@ -1291,7 +1292,7 @@ public:
 
                     /** Creates a ScLookupCache cache for the range if it
                         doesn't already exist. */
-    ScLookupCache & GetLookupCache( const ScRange & rRange );
+    ScLookupCache & GetLookupCache( const ScRange & rRange, ScInterpreterContext* pContext );
                     /** Only ScLookupCache dtor uses RemoveLookupCache(), do
                         not use elsewhere! */
     void            RemoveLookupCache( ScLookupCache & rCache );
@@ -2494,6 +2495,8 @@ private:
 
     void EndListeningGroups( const std::vector<ScAddress>& rPosArray );
     void SetNeedsListeningGroups( const std::vector<ScAddress>& rPosArray );
+
+    bool RemoveLookupCacheHelper( ScLookupCacheMap* cacheMap, ScLookupCache& rCache );
 };
 
 typedef std::unique_ptr<ScDocument, o3tl::default_delete<ScDocument>> ScDocumentUniquePtr;
diff --git a/sc/inc/interpretercontext.hxx b/sc/inc/interpretercontext.hxx
index 8b920472fb44..2855370e7b09 100644
--- a/sc/inc/interpretercontext.hxx
+++ b/sc/inc/interpretercontext.hxx
@@ -18,6 +18,7 @@
 
 class ScDocument;
 class SvNumberFormatter;
+struct ScLookupCacheMap;
 
 // SetNumberFormat() is not thread-safe, so calls to it need to be delayed to the main thread.
 struct DelayedSetNumberFormat
@@ -33,21 +34,18 @@ struct ScInterpreterContext
     size_t mnTokenCachePos;
     std::vector<formula::FormulaToken*> maTokens;
     std::vector<DelayedSetNumberFormat> maDelayedSetNumberFormat;
+    ScLookupCacheMap* mScLookupCache; // cache for lookups like VLOOKUP and MATCH
 
     ScInterpreterContext(const ScDocument& rDoc, SvNumberFormatter* pFormatter)
         : mrDoc(rDoc)
         , mpFormatter(pFormatter)
         , mnTokenCachePos(0)
         , maTokens(TOKEN_CACHE_SIZE, nullptr)
+        , mScLookupCache(nullptr)
     {
     }
 
-    ~ScInterpreterContext()
-    {
-        for (auto p : maTokens)
-            if (p)
-                p->DecRef();
-    }
+    ~ScInterpreterContext();
 
     SvNumberFormatter* GetFormatTable() const { return mpFormatter; }
 };
diff --git a/sc/inc/lookupcache.hxx b/sc/inc/lookupcache.hxx
index fa55c2bcbced..15ec15f086b1 100644
--- a/sc/inc/lookupcache.hxx
+++ b/sc/inc/lookupcache.hxx
@@ -23,6 +23,7 @@
 #include "address.hxx"
 #include <svl/listener.hxx>
 
+#include <memory>
 #include <unordered_map>
 
 class ScDocument;
@@ -189,6 +190,13 @@ private:
 
 };
 
+// Struct because including lookupcache.hxx in document.hxx isn't wanted.
+struct ScLookupCacheMap
+{
+    std::unordered_map< ScRange, std::unique_ptr<ScLookupCache>, ScLookupCache::Hash > aCacheMap;
+};
+
+
 #endif
 
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