package/source/zipapi/CRC32.cxx

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  30
  31 // MARKER(update_precomp.py): autogen include statement, do not remove
  32 #include "precompiled_package.hxx"
  33 #include <CRC32.hxx>
  34 #ifndef _ZLIB_H
  35 #ifdef SYSTEM_ZLIB
  36 #include <zlib.h>
  37 #else
  38 #include <external/zlib/zlib.h>
  39 #endif
  40 #endif
  41 #include <PackageConstants.hxx>
  42 #include <com/sun/star/io/XInputStream.hpp>
  43
  44 using namespace rtl;
  45 using namespace com::sun::star::uno;
  46 using namespace com::sun::star::io;
  47
  48 /** A class to compute the CRC32 value of a data stream
  49  */
  50
  51 CRC32::CRC32()
  52 : nCRC(0)
  53 {
  54 }
  55 CRC32::~CRC32()
  56 {
  57 }
  58 void SAL_CALL CRC32::reset()
  59     throw(RuntimeException)
  60 {
  61     nCRC=0;
  62 }
  63 sal_Int32 SAL_CALL CRC32::getValue()
  64     throw(RuntimeException)
  65 {
  66     return nCRC & 0xFFFFFFFFL;
  67 }
  68 /** Update CRC32 with specified sequence of bytes
  69  */
  70 void SAL_CALL CRC32::updateSegment(const Sequence< sal_Int8 > &b,
  71                                     sal_Int32 off,
  72                                     sal_Int32 len)
  73         throw(RuntimeException)
  74 {
  75     nCRC = crc32(nCRC, (const unsigned char*)b.getConstArray()+off, len );
  76 }
  77 /** Update CRC32 with specified sequence of bytes
  78  */
  79 void SAL_CALL CRC32::update(const Sequence< sal_Int8 > &b)
  80         throw(RuntimeException)
  81 {
  82     nCRC = crc32(nCRC, (const unsigned char*)b.getConstArray(),b.getLength());
  83 }
  84
  85 sal_Int32 SAL_CALL CRC32::updateStream( Reference < XInputStream > & xStream )
  86     throw ( RuntimeException )
  87 {
  88     sal_Int32 nLength, nTotal = 0;
  89     Sequence < sal_Int8 > aSeq ( n_ConstBufferSize );
  90     do
  91     {
  92         nLength = xStream->readBytes ( aSeq, n_ConstBufferSize );
  93         updateSegment ( aSeq, 0, nLength );
  94         nTotal += nLength;
  95     }
  96     while ( nLength == n_ConstBufferSize );
  97
  98     return nTotal;
  99 }