public unsafe void XXHash64_StreamedHashingEquivalence(int bufferSize)
{
var rnd = new Random(1000);
byte[] values = new byte[bufferSize];
rnd.NextBytes(values);
uint seed = 233;
int blockSize;
int iteration = 1;
do
{
blockSize = Hashing.Streamed.XXHash64.Alignment * iteration;
var context = new Hashing.Streamed.XXHash64Context {
Seed = seed
};
Hashing.Streamed.XXHash64.BeginProcess(ref context);
fixed(byte *buffer = values)
{
byte *current = buffer;
byte *bEnd = buffer + bufferSize;
do
{
int block = Math.Min(blockSize, (int)(bEnd - current));
Hashing.Streamed.XXHash64.Process(ref context, current, block);
current += block;
}while (current < bEnd);
}
iteration++;
var result = Hashing.Streamed.XXHash64.EndProcess(ref context);
var expected = Hashing.XXHash64.Calculate(values, -1, seed);
Assert.Equal(expected, result);
}while (blockSize <= bufferSize);
}
public static ulong CalculateFileHeaderHash(FileHeader *header)
{
var ctx = new Hashing.Streamed.XXHash64Context
{
Seed = (ulong)header->TransactionId
};
Hashing.Streamed.XXHash64.BeginProcess(ref ctx);
// First part of header, until the Hash field
Hashing.Streamed.XXHash64.Process(ref ctx, (byte *)header, FileHeader.HashOffset);
// Second part of header, after the hash field
var secondPartOfHeaderLength = sizeof(FileHeader) - (FileHeader.HashOffset + sizeof(ulong));
if (secondPartOfHeaderLength > 0)
{
Hashing.Streamed.XXHash64.Process(ref ctx, (byte *)header + FileHeader.HashOffset + sizeof(ulong), secondPartOfHeaderLength);
}
return(Hashing.Streamed.XXHash64.EndProcess(ref ctx));
}
