package/source/zipapi/CRC32.cxx

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  27
  28 // MARKER(update_precomp.py): autogen include statement, do not remove
  29 #include "precompiled_package.hxx"
  30 #include <CRC32.hxx>
  31 #ifndef _ZLIB_H
  32 #ifdef SYSTEM_ZLIB
  33 #include <zlib.h>
  34 #else
  35 #include <external/zlib/zlib.h>
  36 #endif
  37 #endif
  38 #include <PackageConstants.hxx>
  39 #include <com/sun/star/io/XInputStream.hpp>
  40
  41 using namespace rtl;
  42 using namespace com::sun::star::uno;
  43 using namespace com::sun::star::io;
  44
  45 /** A class to compute the CRC32 value of a data stream
  46  */
  47
  48 CRC32::CRC32()
  49 : nCRC(0)
  50 {
  51 }
  52 CRC32::~CRC32()
  53 {
  54 }
  55 void SAL_CALL CRC32::reset()
  56     throw(RuntimeException)
  57 {
  58     nCRC=0;
  59 }
  60 sal_Int32 SAL_CALL CRC32::getValue()
  61     throw(RuntimeException)
  62 {
  63     return nCRC & 0xFFFFFFFFL;
  64 }
  65 /** Update CRC32 with specified sequence of bytes
  66  */
  67 void SAL_CALL CRC32::updateSegment(const Sequence< sal_Int8 > &b,
  68                                     sal_Int32 off,
  69                                     sal_Int32 len)
  70         throw(RuntimeException)
  71 {
  72     nCRC = crc32(nCRC, (const unsigned char*)b.getConstArray()+off, len );
  73 }
  74 /** Update CRC32 with specified sequence of bytes
  75  */
  76 void SAL_CALL CRC32::update(const Sequence< sal_Int8 > &b)
  77         throw(RuntimeException)
  78 {
  79     nCRC = crc32(nCRC, (const unsigned char*)b.getConstArray(),b.getLength());
  80 }
  81
  82 sal_Int32 SAL_CALL CRC32::updateStream( Reference < XInputStream > & xStream )
  83     throw ( RuntimeException )
  84 {
  85     sal_Int32 nLength, nTotal = 0;
  86     Sequence < sal_Int8 > aSeq ( n_ConstBufferSize );
  87     do
  88     {
  89         nLength = xStream->readBytes ( aSeq, n_ConstBufferSize );
  90         updateSegment ( aSeq, 0, nLength );
  91         nTotal += nLength;
  92     }
  93     while ( nLength == n_ConstBufferSize );
  94
  95     return nTotal;
  96 }