tdf#62525: use cow_wrapper for SvGlobalName

Convert the pimpled copy-on-write SvGlobalName class to use the
::o3tl::cow_wrapper using the default reference counting policy.

Change-Id: I7bceb06ddfb31ca5901e5e7d5d93dda494db945f
Reviewed-on: https://gerrit.libreoffice.org/18070
Reviewed-by: Thorsten Behrens <Thorsten.Behrens@CIB.de>
Tested-by: Thorsten Behrens <Thorsten.Behrens@CIB.de>

include/tools/globname.hxx

@@ -23,6 +23,7 @@
 
 #include <tools/toolsdllapi.h>
 #include <com/sun/star/uno/Sequence.hxx>
+#include <o3tl/cow_wrapper.hxx>
 
 struct SvGUID
 {
@@ -35,20 +36,16 @@ struct SvGUID
 struct ImpSvGlobalName
 {
     struct SvGUID   szData;
-    sal_uInt16      nRefCount;
-
-    enum Empty { EMPTY };
 
     ImpSvGlobalName(const SvGUID &rData)
         : szData(rData)
-                    , nRefCount(0)
     {
     }
     ImpSvGlobalName(sal_uInt32 n1, sal_uInt16 n2, sal_uInt16 n3,
               sal_uInt8 b8, sal_uInt8 b9, sal_uInt8 b10, sal_uInt8 b11,
               sal_uInt8 b12, sal_uInt8 b13, sal_uInt8 b14, sal_uInt8 b15);
     ImpSvGlobalName( const ImpSvGlobalName & rObj );
-                ImpSvGlobalName( Empty );
+    ImpSvGlobalName();
 
     bool        operator == ( const ImpSvGlobalName & rObj ) const;
 };
@@ -57,21 +54,15 @@ class SvStream;
 
 class TOOLS_DLLPUBLIC SvGlobalName
 {
-    ImpSvGlobalName * pImp;
+    ::o3tl::cow_wrapper< ImpSvGlobalName > pImp;
-    void    NewImp();
 
 public:
     SvGlobalName();
-            SvGlobalName( const SvGlobalName & rObj )
+    SvGlobalName( const SvGlobalName & rObj ) :
+        pImp( rObj.pImp )
     {
-                pImp = rObj.pImp;
-                pImp->nRefCount++;
-            }
-            SvGlobalName( ImpSvGlobalName * pImpP )
-            {
-                pImp = pImpP;
-                pImp->nRefCount++;
     }
+
     SvGlobalName( sal_uInt32 n1, sal_uInt16 n2, sal_uInt16 n3,
                   sal_uInt8 b8, sal_uInt8 b9, sal_uInt8 b10, sal_uInt8 b11,
                   sal_uInt8 b12, sal_uInt8 b13, sal_uInt8 b14, sal_uInt8 b15 );
@@ -79,6 +70,8 @@ public:
     // create SvGlobalName from a platform independent representation
     SvGlobalName( const ::com::sun::star::uno::Sequence< sal_Int8 >& aSeq );
 
+    SvGlobalName( const SvGUID & rId );
+
     SvGlobalName & operator = ( const SvGlobalName & rObj );
     ~SvGlobalName();
 
@@ -97,7 +90,6 @@ public:
     bool          MakeId( const OUString & rId );
     OUString      GetHexName() const;
 
-                  SvGlobalName( const SvGUID & rId );
     const SvGUID& GetCLSID() const { return pImp->szData; }
 
     // platform independent representation of a "GlobalName"

tools/source/ref/globname.cxx

@@ -27,22 +27,19 @@
 #include <tools/globname.hxx>
 
 // ImpSvGlobalName ------------------------------------------------------------
-ImpSvGlobalName::ImpSvGlobalName( const ImpSvGlobalName & rObj )
+ImpSvGlobalName::ImpSvGlobalName()
-    : szData(rObj.szData)
-    , nRefCount(0)
-{
-}
-
-ImpSvGlobalName::ImpSvGlobalName( Empty )
-    : nRefCount(1)
 {
     memset( &szData, 0, sizeof( szData ) );
 }
 
+ImpSvGlobalName::ImpSvGlobalName( const ImpSvGlobalName & rObj )
+    : szData(rObj.szData)
+{
+}
+
 ImpSvGlobalName::ImpSvGlobalName(sal_uInt32 n1, sal_uInt16 n2, sal_uInt16 n3,
                           sal_uInt8 b8, sal_uInt8 b9, sal_uInt8 b10, sal_uInt8 b11,
                           sal_uInt8 b12, sal_uInt8 b13, sal_uInt8 b14, sal_uInt8 b15)
-    : nRefCount(0)
 {
     szData.Data1 = n1;
     szData.Data2 = n2;
@@ -63,53 +60,49 @@ bool ImpSvGlobalName::operator == ( const ImpSvGlobalName & rObj ) const
 }
 
 // SvGlobalName ----------------------------------------------------------------
-SvGlobalName::SvGlobalName()
+SvGlobalName::SvGlobalName() :
+    pImp()
 {
-    static ImpSvGlobalName aNoName( ImpSvGlobalName::EMPTY );
-
-    pImp = &aNoName;
-    pImp->nRefCount++;
 }
 
-SvGlobalName::SvGlobalName( const SvGUID & rId )
+SvGlobalName::SvGlobalName( const SvGUID & rId ) :
+    pImp( ImpSvGlobalName( rId ) )
 {
-    pImp = new ImpSvGlobalName(rId);
-    pImp->nRefCount++;
 }
 
 SvGlobalName::SvGlobalName( sal_uInt32 n1, sal_uInt16 n2, sal_uInt16 n3,
                             sal_uInt8 b8, sal_uInt8 b9, sal_uInt8 b10, sal_uInt8 b11,
-                            sal_uInt8 b12, sal_uInt8 b13, sal_uInt8 b14, sal_uInt8 b15 )
+                            sal_uInt8 b12, sal_uInt8 b13, sal_uInt8 b14, sal_uInt8 b15 ) :
+    pImp( ImpSvGlobalName(n1, n2, n3, b8, b9, b10, b11, b12, b13, b14, b15) )
 {
-    pImp = new ImpSvGlobalName(n1, n2, n3, b8, b9, b10, b11, b12, b13, b14, b15);
+}
-    pImp->nRefCount++;
+
+SvGlobalName::SvGlobalName( const com::sun::star::uno::Sequence < sal_Int8 >& aSeq )
+{
+    // create SvGlobalName from a platform independent representation
+    SvGUID aResult;
+    memset( &aResult, 0, sizeof( aResult ) );
+    if ( aSeq.getLength() == 16 )
+    {
+        aResult.Data1 = ( ( ( ( ( ( sal_uInt8 )aSeq[0] << 8 ) + ( sal_uInt8 )aSeq[1] ) << 8 ) + ( sal_uInt8 )aSeq[2] ) << 8 ) + ( sal_uInt8 )aSeq[3];
+        aResult.Data2 = ( ( sal_uInt8 )aSeq[4] << 8 ) + ( sal_uInt8 )aSeq[5];
+        aResult.Data3 = ( ( sal_uInt8 )aSeq[6] << 8 ) + ( sal_uInt8 )aSeq[7];
+        for( int nInd = 0; nInd < 8; nInd++ )
+            aResult.Data4[nInd] = ( sal_uInt8 )aSeq[nInd+8];
+    }
+
+    pImp = ::o3tl::cow_wrapper< ImpSvGlobalName >(aResult);
 }
 
 SvGlobalName::~SvGlobalName()
 {
-    pImp->nRefCount--;
-    if( !pImp->nRefCount )
-        delete pImp;
 }
 
 SvGlobalName & SvGlobalName::operator = ( const SvGlobalName & rObj )
 {
-    rObj.pImp->nRefCount++;
-    pImp->nRefCount--;
-    if( !pImp->nRefCount )
-        delete pImp;
     pImp = rObj.pImp;
-    return *this;
-}
 
-void SvGlobalName::NewImp()
+    return *this;
-{
-    if( pImp->nRefCount > 1 )
-    {
-        pImp->nRefCount--;
-        pImp = new ImpSvGlobalName( *pImp );
-        pImp->nRefCount++;
-    }
 }
 
 SvStream& WriteSvGlobalName( SvStream& rOStr, const SvGlobalName & rObj )
@@ -123,7 +116,8 @@ SvStream& WriteSvGlobalName( SvStream& rOStr, const SvGlobalName & rObj )
 
 SvStream& operator >> ( SvStream& rStr, SvGlobalName & rObj )
 {
-    rObj.NewImp(); // copy if necessary
+    // the non-const dereferencing operator
+    // ensures pImp is unique
     rStr.ReadUInt32( rObj.pImp->szData.Data1 );
     rStr.ReadUInt16( rObj.pImp->szData.Data2 );
     rStr.ReadUInt16( rObj.pImp->szData.Data3 );
@@ -149,8 +143,6 @@ bool SvGlobalName::operator < ( const SvGlobalName & rObj ) const
 
 SvGlobalName & SvGlobalName::operator += ( sal_uInt32 n )
 {
-    NewImp();
-
     sal_uInt32 nOld = pImp->szData.Data1;
     pImp->szData.Data1 += n;
 
@@ -164,12 +156,11 @@ SvGlobalName & SvGlobalName::operator += ( sal_uInt32 n )
 
 bool SvGlobalName::operator == ( const SvGlobalName & rObj ) const
 {
-    return *pImp == *rObj.pImp;
+    return pImp == rObj.pImp;
 }
 
 void SvGlobalName::MakeFromMemory( void * pData )
 {
-    NewImp();
     memcpy( &pImp->szData, pData, sizeof( pImp->szData ) );
 }
 
@@ -241,7 +232,6 @@ bool SvGlobalName::MakeId( const OUString & rIdStr )
                 pStr++;
         }
 
-        NewImp();
         memcpy(&pImp->szData.Data1, &nFirst, sizeof(nFirst));
         memcpy(&pImp->szData.Data2, &nSec, sizeof(nSec));
         memcpy(&pImp->szData.Data3, &nThird, sizeof(nThird));
@@ -305,22 +295,4 @@ com::sun::star::uno::Sequence < sal_Int8 > SvGlobalName::GetByteSequence() const
     return aResult;
 }
 
-SvGlobalName::SvGlobalName( const com::sun::star::uno::Sequence < sal_Int8 >& aSeq )
-{
-    // create SvGlobalName from a platform independent representation
-    SvGUID aResult;
-    memset( &aResult, 0, sizeof( aResult ) );
-    if ( aSeq.getLength() == 16 )
-    {
-        aResult.Data1 = ( ( ( ( ( ( sal_uInt8 )aSeq[0] << 8 ) + ( sal_uInt8 )aSeq[1] ) << 8 ) + ( sal_uInt8 )aSeq[2] ) << 8 ) + ( sal_uInt8 )aSeq[3];
-        aResult.Data2 = ( ( sal_uInt8 )aSeq[4] << 8 ) + ( sal_uInt8 )aSeq[5];
-        aResult.Data3 = ( ( sal_uInt8 )aSeq[6] << 8 ) + ( sal_uInt8 )aSeq[7];
-        for( int nInd = 0; nInd < 8; nInd++ )
-            aResult.Data4[nInd] = ( sal_uInt8 )aSeq[nInd+8];
-    }
-
-    pImp = new ImpSvGlobalName(aResult);
-    pImp->nRefCount++;
-}
-
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