Resolves: tdf#115750 SvStream::WriteStream was broken

and didn't stop copying at the size limit arg

(cherry picked from commit bcdaaf62d41728eb757ff2b9cb95c2df2791e2f4)

Change-Id: I8f1be0310160f5158d2f64c62d6b2c09c0157930

1 files changed, 5 insertions, 6 deletions

diff --git a/tools/source/stream/stream.cxx b/tools/source/stream/stream.cxx
index b83729e35fbf..530f6e8c0620 100644
--- a/tools/source/stream/stream.cxx
+++ b/tools/source/stream/stream.cxx
@@ -1184,13 +1184,12 @@ sal_uInt64 SvStream::WriteStream( SvStream& rStream, sal_uInt64 nSize )
     sal_uInt32 nCount;
     sal_uInt64 nWriteSize = nSize;
 
-    do {
-        if ( nSize >= nCurBufLen )
-            nWriteSize -= nCurBufLen;
-        else
-            nCurBufLen = nWriteSize;
-        nCount = rStream.ReadBytes( pBuf.get(), nCurBufLen );
+    do
+    {
+        nCurBufLen = std::min<sal_uInt64>(nCurBufLen, nWriteSize);
+        nCount = rStream.ReadBytes(pBuf.get(), nCurBufLen);
         WriteBytes( pBuf.get(), nCount );
+        nWriteSize -= nCount;
     }
     while( nWriteSize && nCount == nCurBufLen );