Kill SvNullStream duplication

2 files changed, 31 insertions, 3 deletions

diff --git a/filter/inc/filter/msfilter/escherex.hxx b/filter/inc/filter/msfilter/escherex.hxx
index 94f700f2ae4c..bfd78364a42c 100644
--- a/filter/inc/filter/msfilter/escherex.hxx
+++ b/filter/inc/filter/msfilter/escherex.hxx
@@ -1560,6 +1560,7 @@ class MSFILTER_DLLPUBLIC EscherEx : public EscherPersistTable
         EscherExGlobalRef           mxGlobal;
         ImplEscherExSdrPtr          mpImplEscherExSdr;
         SvStream*                   mpOutStrm;
+        bool                        mbOwnsStrm;
         sal_uInt32                  mnStrmStartOfs;
         std::vector< sal_uInt32 >   mOffsets;
         std::vector< sal_uInt16 >   mRecTypes;
@@ -1578,7 +1579,7 @@ class MSFILTER_DLLPUBLIC EscherEx : public EscherPersistTable
         virtual sal_Bool DoSeek( sal_uInt32 nKey );
 
 public:
-    explicit            EscherEx( const EscherExGlobalRef& rxGlobal, SvStream& rOutStrm );
+    explicit            EscherEx( const EscherExGlobalRef& rxGlobal, SvStream* pOutStrm );
     virtual             ~EscherEx();
 
     /** Creates and returns a new shape identifier, updates the internal shape
diff --git a/filter/source/msfilter/escherex.cxx b/filter/source/msfilter/escherex.cxx
index 5aac23ddbdd5..6fdbcd4c3773 100644
--- a/filter/source/msfilter/escherex.cxx
+++ b/filter/source/msfilter/escherex.cxx
@@ -4365,9 +4365,29 @@ SvStream* EscherExGlobal::ImplQueryPictureStream()
     return 0;
 }
 
-EscherEx::EscherEx( const EscherExGlobalRef& rxGlobal, SvStream& rOutStrm ) :
+/// Implementation of an empty stream that silently succeeds, but does nothing.
+///
+/// In fact, this is a hack.  The right solution is to abstract EscherEx to be
+/// able to work without SvStream; but at the moment it is better to live with
+/// this I guess.
+class SvNullStream : public SvStream
+{
+protected:
+    virtual sal_Size GetData( void* pData, sal_Size nSize ) { memset( pData, 0, nSize ); return nSize; }
+    virtual sal_Size PutData( const void*, sal_Size nSize ) { return nSize; }
+    virtual sal_Size SeekPos( sal_Size nPos ) { return nPos; }
+    virtual void SetSize( sal_Size ) {}
+    virtual void FlushData() {}
+
+public:
+    SvNullStream() : SvStream() {}
+    virtual ~SvNullStream() {}
+};
+
+EscherEx::EscherEx( const EscherExGlobalRef& rxGlobal, SvStream* pOutStrm ) :
     mxGlobal                ( rxGlobal ),
-    mpOutStrm               ( &rOutStrm ),
+    mpOutStrm               ( pOutStrm ),
+    mbOwnsStrm              ( false ),
 
     mnCurrentDg                         ( 0 ),
 
@@ -4377,12 +4397,19 @@ EscherEx::EscherEx( const EscherExGlobalRef& rxGlobal, SvStream& rOutStrm ) :
     mbEscherSpgr            ( sal_False ),
     mbEscherDg              ( sal_False )
 {
+    if (!mpOutStrm)
+    {
+        mpOutStrm = new SvNullStream();
+        mbOwnsStrm = true;
+    }
     mnStrmStartOfs = mpOutStrm->Tell();
     mpImplEscherExSdr.reset( new ImplEscherExSdr( *this ) );
 }
 
 EscherEx::~EscherEx()
 {
+    if (mbOwnsStrm)
+        delete mpOutStrm;
 }
 
 void EscherEx::Flush( SvStream* pPicStreamMergeBSE /* = NULL */ )