1 files changed, 72 insertions, 0 deletions
diff --git a/package/source/zipapi/CRC32.cxx b/package/source/zipapi/CRC32.cxx
new file mode 100644
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--- /dev/null
+++ b/package/source/zipapi/CRC32.cxx
@@ -0,0 +1,72 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ *   Licensed to the Apache Software Foundation (ASF) under one or more
+ *   contributor license agreements. See the NOTICE file distributed
+ *   with this work for additional information regarding copyright
+ *   ownership. The ASF licenses this file to you under the Apache
+ *   License, Version 2.0 (the "License"); you may not use this file
+ *   except in compliance with the License. You may obtain a copy of
+ *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#include <CRC32.hxx>
+#include <PackageConstants.hxx>
+#include <rtl/crc.h>
+#include <com/sun/star/io/XInputStream.hpp>
+
+using namespace com::sun::star::uno;
+using namespace com::sun::star::io;
+
+/** A class to compute the CRC32 value of a data stream
+ */
+
+CRC32::CRC32()
+: nCRC(0)
+{
+}
+void CRC32::reset()
+{
+    nCRC=0;
+}
+sal_Int32 CRC32::getValue() const
+{
+    return nCRC;
+}
+/** Update CRC32 with specified sequence of bytes
+ */
+void CRC32::updateSegment(const Sequence< sal_Int8 > &b, sal_Int32 len)
+{
+    nCRC = rtl_crc32(nCRC, b.getConstArray(), len );
+}
+/** Update CRC32 with specified sequence of bytes
+ */
+void CRC32::update(const Sequence< sal_Int8 > &b)
+{
+    nCRC = rtl_crc32(nCRC, b.getConstArray(),b.getLength());
+}
+
+sal_Int64 CRC32::updateStream( Reference < XInputStream > const & xStream )
+{
+    sal_Int32 nLength;
+    sal_Int64 nTotal = 0;
+    Sequence < sal_Int8 > aSeq ( n_ConstBufferSize );
+    do
+    {
+        nLength = xStream->readBytes ( aSeq, n_ConstBufferSize );
+        updateSegment ( aSeq, nLength );
+        nTotal += nLength;
+    }
+    while ( nLength == n_ConstBufferSize );
+
+    return nTotal;
+}
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */