Esempio n. 1
0
static UInt32 NO_INLINE DecodeBlock2Rand(const UInt32 *tt, UInt32 blockSize, UInt32 OrigPtr, COutBuffer &m_OutStream)
{
  CBZip2Crc crc;

  UInt32 randIndex = 1;
  UInt32 randToGo = kRandNums[0] - 2;

  unsigned numReps = 0;

  // it's for speed optimization: prefetch & prevByte_init;
  UInt32 tPos = tt[tt[OrigPtr] >> 8];
  unsigned prevByte = (unsigned)(tPos & 0xFF);

  do
  {
    unsigned b = (unsigned)(tPos & 0xFF);
    tPos = tt[tPos >> 8];

    {
      if (randToGo == 0)
      {
        b ^= 1;
        randToGo = kRandNums[randIndex++];
        randIndex &= 0x1FF;
      }
      randToGo--;
    }

    if (numReps == kRleModeRepSize)
    {
      for (; b > 0; b--)
      {
        crc.UpdateByte(prevByte);
        m_OutStream.WriteByte((Byte)prevByte);
      }
      numReps = 0;
      continue;
    }
    if (b != prevByte)
      numReps = 0;
    numReps++;
    prevByte = b;
    crc.UpdateByte(b);
    m_OutStream.WriteByte((Byte)b);
  }
  while (--blockSize != 0);
  return crc.GetDigest();
}
Esempio n. 2
0
// blockSize > 0
UInt32 CThreadInfo::EncodeBlockWithHeaders(const Byte *block, UInt32 blockSize)
{
  WriteByte2(kBlockSig0);
  WriteByte2(kBlockSig1);
  WriteByte2(kBlockSig2);
  WriteByte2(kBlockSig3);
  WriteByte2(kBlockSig4);
  WriteByte2(kBlockSig5);

  CBZip2Crc crc;
  int numReps = 0;
  Byte prevByte = block[0];
  UInt32 i = 0;
  do
  {
    Byte b = block[i];
    if (numReps == kRleModeRepSize)
    {
      for (; b > 0; b--)
        crc.UpdateByte(prevByte);
      numReps = 0;
      continue;
    }
    if (prevByte == b)
      numReps++;
    else
    {
      numReps = 1;
      prevByte = b;
    }
    crc.UpdateByte(b);
  }
  while (++i < blockSize);
  UInt32 crcRes = crc.GetDigest();
  WriteCrc2(crcRes);
  EncodeBlock(block, blockSize);
  return crcRes;
}
Esempio n. 3
0
static UInt32 NO_INLINE DecodeBlock2(const UInt32 *tt, UInt32 blockSize, UInt32 OrigPtr, COutBuffer &m_OutStream)
{
  CBZip2Crc crc;

  // it's for speed optimization: prefetch & prevByte_init;
  UInt32 tPos = tt[tt[OrigPtr] >> 8];
  unsigned prevByte = (unsigned)(tPos & 0xFF);

  unsigned numReps = 0;

  do
  {
    unsigned b = (unsigned)(tPos & 0xFF);
    tPos = tt[tPos >> 8];

    if (numReps == kRleModeRepSize)
    {
      for (; b > 0; b--)
      {
        crc.UpdateByte(prevByte);
        m_OutStream.WriteByte((Byte)prevByte);
      }
      numReps = 0;
      continue;
    }
    if (b != prevByte)
      numReps = 0;
    numReps++;
    prevByte = b;
    crc.UpdateByte(b);
    m_OutStream.WriteByte((Byte)b);

    /*
    prevByte = b;
    crc.UpdateByte(b);
    m_OutStream.WriteByte((Byte)b);
    for (; --blockSize != 0;)
    {
      b = (unsigned)(tPos & 0xFF);
      tPos = tt[tPos >> 8];
      crc.UpdateByte(b);
      m_OutStream.WriteByte((Byte)b);
      if (b != prevByte)
      {
        prevByte = b;
        continue;
      }
      if (--blockSize == 0)
        break;

      b = (unsigned)(tPos & 0xFF);
      tPos = tt[tPos >> 8];
      crc.UpdateByte(b);
      m_OutStream.WriteByte((Byte)b);
      if (b != prevByte)
      {
        prevByte = b;
        continue;
      }
      if (--blockSize == 0)
        break;

      b = (unsigned)(tPos & 0xFF);
      tPos = tt[tPos >> 8];
      crc.UpdateByte(b);
      m_OutStream.WriteByte((Byte)b);
      if (b != prevByte)
      {
        prevByte = b;
        continue;
      }
      --blockSize;
      break;
    }
    if (blockSize == 0)
      break;

    b = (unsigned)(tPos & 0xFF);
    tPos = tt[tPos >> 8];

    for (; b > 0; b--)
    {
      crc.UpdateByte(prevByte);
      m_OutStream.WriteByte((Byte)prevByte);
    }
    */
  }
  while (--blockSize != 0);
  return crc.GetDigest();
}