/// <summary>
///
/// </summary>
/// <param name="fileName"></param>
/// <param name="size"></param>
/// <returns></returns>
public byte[] FileCheckSum(string fileName, int size)
{
var mdFour = new MdFour(_options);
using (var fileStream = new FileStream(fileName, FileMode.Open, FileAccess.Read, FileShare.Read))
{
var buf = new MapFile(fileStream, size, Options.MaxMapSize, CsumChunk);
mdFour.Begin();
int i;
for (i = 0; i + CsumChunk <= size; i += CsumChunk)
{
var offset = buf.MapPtr(i, CsumChunk);
mdFour.Update(buf.P, offset, CsumChunk);
}
if (size - i > 0 || _options.ProtocolVersion >= 27)
{
var offset = buf.MapPtr(i, size - i);
mdFour.Update(buf.P, offset, (UInt32)(size - i));
}
fileStream.Close();
return(mdFour.Result());
}
}
/// <summary>
///
/// </summary>
/// <param name="buf"></param>
/// <param name="pos"></param>
/// <param name="len"></param>
/// <returns></returns>
public byte[] GetChecksum2(byte[] buf, int pos, int len)
{
var buf1 = new byte[len + 4];
for (var j = 0; j < len; j++)
{
buf1[j] = buf[pos + j];
}
var mdFour = new MdFour(_options);
mdFour.Begin();
if (_options.ChecksumSeed != 0)
{
Sival(ref buf1, len, (UInt32)_options.ChecksumSeed);
len += 4;
}
int i;
for (i = 0; i + CsumChunk <= len; i += CsumChunk)
{
mdFour.Update(buf1, i, CsumChunk);
}
if (len - i > 0 || _options.ProtocolVersion >= 27)
{
mdFour.Update(buf1, i, (UInt32)(len - i));
}
return(mdFour.Result());
}
public void Update(byte[] p, int ind, int len)
{
var pPos = 0;
if (len + SumResidue < CheckSum.CsumChunk)
{
for (var j = 0; j < len; j++)
{
Sumrbuf[SumResidue + j] = p[j + ind];
}
SumResidue += len;
return;
}
if (SumResidue != 0)
{
var min = Math.Min(CheckSum.CsumChunk - SumResidue, len);
for (var j = 0; j < min; j++)
{
Sumrbuf[SumResidue + j] = p[j + ind];
}
Md.Update(Sumrbuf, 0, (UInt32)(min + SumResidue));
len -= min;
pPos += min;
}
int i;
for (i = 0; i + CheckSum.CsumChunk <= len; i += CheckSum.CsumChunk)
{
for (var j = 0; j < CheckSum.CsumChunk; j++)
{
Sumrbuf[j] = p[pPos + i + j + ind];
}
Md.Update(Sumrbuf, 0, CheckSum.CsumChunk);
}
if (len - i > 0)
{
SumResidue = len - i;
for (var j = 0; j < SumResidue; j++)
{
Sumrbuf[j] = p[pPos + i + j + ind];
}
}
else
{
SumResidue = 0;
}
}
