package/source/zipapi/CRC32.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #include <CRC32.hxx>
  21 #include <PackageConstants.hxx>
  22 #include <rtl/crc.h>
  23 #include <com/sun/star/io/XInputStream.hpp>
  24
  25 using namespace com::sun::star::uno;
  26 using namespace com::sun::star::io;
  27
  28 /** A class to compute the CRC32 value of a data stream
  29  */
  30
  31 CRC32::CRC32()
  32 : nCRC(0)
  33 {
  34 }
  35 CRC32::~CRC32()
  36 {
  37 }
  38 void CRC32::reset()
  39 {
  40     nCRC=0;
  41 }
  42 sal_Int32 CRC32::getValue()
  43 {
  44     return nCRC & 0xFFFFFFFFL;
  45 }
  46 /** Update CRC32 with specified sequence of bytes
  47  */
  48 void CRC32::updateSegment(const Sequence< sal_Int8 > &b, sal_Int32 len)
  49 {
  50     nCRC = rtl_crc32(nCRC, b.getConstArray(), len );
  51 }
  52 /** Update CRC32 with specified sequence of bytes
  53  */
  54 void CRC32::update(const Sequence< sal_Int8 > &b)
  55 {
  56     nCRC = rtl_crc32(nCRC, b.getConstArray(),b.getLength());
  57 }
  58
  59 sal_Int64 CRC32::updateStream( Reference < XInputStream > const & xStream )
  60 {
  61     sal_Int32 nLength;
  62     sal_Int64 nTotal = 0;
  63     Sequence < sal_Int8 > aSeq ( n_ConstBufferSize );
  64     do
  65     {
  66         nLength = xStream->readBytes ( aSeq, n_ConstBufferSize );
  67         updateSegment ( aSeq, nLength );
  68         nTotal += nLength;
  69     }
  70     while ( nLength == n_ConstBufferSize );
  71
  72     return nTotal;
  73 }
  74
  75 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */