private static string Hash(string plain)
{
ulong hash = XXHash64.Hash(plain);
byte[] buffer = BitConverter.GetBytes(hash);
return(BitConverter.ToString(buffer).Replace("-", "").ToLower());
}
private static string Hash(string key)
{
switch (FileNameStyle)
{
case KeyStyle.Hashed:
{
var hash = XXHash64.Hash(key);
Span <byte> bytes = stackalloc byte[10];
Utf8Formatter.TryFormat(hash, bytes, out var bytesWritten);
// This requires netcoreapp3.1 or net5
// return MemoryMarshal.AsRef<char>(bytes.Slice(0, bytesWritten)).ToString();
return(DefaultEncoding.GetString(bytes.Slice(0, bytesWritten).ToArray()));
}
case KeyStyle.Base64:
{
var bytes = DefaultEncoding.GetBytes(key);
return(UrlBase64.Encode(bytes));
}
case KeyStyle.PlainText:
{
if (key.ToCharArray().Any(c => Array.BinarySearch(IllegalCharacters, c) >= 0))
{
throw new IllegalKeyException();
}
return(key);
}
}
throw new Exception("Invalid key hashing style set!");
}
public unsafe void SystemImpl()
{
for (int i = 0; i < N; i++)
{
fixed(byte *p = bytes)
{
var hash1 = XXHash64.Hash(bytes, 0, Size, 0);
}
}
}
public void CompHas()
{
using (var sw = File.CreateText(EXPORT_PATH))
{
foreach (var key in hashes)
{
sw.WriteLine($"{key}\t\t = {XXHash64.Hash(0, key)}");
}
}
Assert.True(File.Exists(EXPORT_PATH));
}
public unsafe static void HashRandomBytesFor()
{
Random rd = new Random(Guid.NewGuid().GetHashCode());
ulong hash1 = 0;
for (int n = 1; n <= 32; n++)
{
byte[] bytes = new byte[n];
for (int i = 0; i < bytes.Length; i++)
{
bytes[i] = (byte)rd.Next(0, byte.MaxValue);
}
Stopwatch w = Stopwatch.StartNew();
for (int i = 0; i < 100000000; i++)
{
hash1 = FastHash.Hash(bytes);
}
w.Stop();
long costA = w.ElapsedMilliseconds;
w = Stopwatch.StartNew();
for (int i = 0; i < 100000000; i++)
{
hash1 = XXHash64.Hash(bytes);
}
w.Stop();
long costB = w.ElapsedMilliseconds;
Console.WriteLine($"Length:{n.ToString().PadRight(3,' ')} " +
$"FastHash Cost:{costA.ToString().PadRight(5, ' ')} " +
$"XXHash64 Cost:{costB.ToString().PadRight(5, ' ')} " +
$"Times:{((float)costB/costA).ToString("f3").PadRight(5,' ')}");
}
//rd = new Random(Guid.NewGuid().GetHashCode());
//for (int n = 1; n <= 32; n++)
//{
// byte[] bytes = new byte[n];
// for (int i = 0; i < bytes.Length; i++)
// bytes[i] = (byte)rd.Next(0, byte.MaxValue);
// Stopwatch w = Stopwatch.StartNew();
// for (int i = 0; i < 100000000; i++)
// {
// hash1 = XXHash64.Hash(bytes);
// }
// w.Stop();
// Console.WriteLine($"length:{n} XXHash64 cost:{w.ElapsedMilliseconds}");
//}
}
public unsafe static void HashRandomBytes()
{
Random rd = new Random(Guid.NewGuid().GetHashCode());
byte[] bytes = new byte[1024];
for (int i = 0; i < bytes.Length; i++)
{
bytes[i] = (byte)rd.Next(0, byte.MaxValue);
}
ulong hash1 = 0;
ulong hash2 = 0;
ulong hash3 = 0;
ulong hash4 = 0;
//Stopwatch w = Stopwatch.StartNew();
//fixed (Byte* @in = &bytes[0])
//{
// for (int i = 0; i < 10000000; i++)
// {
// //hash1 = XXHash64.Hash(@in, bytes.Length, 0);
// //XXHash64.Hash(@in, bytes.Length, ref hash1,ref hash2,0,0);
// //XXHash64.Hash(@in, bytes.Length, ref hash1, ref hash2,ref hash3, 0, 0,0);
// XXHash64.Hash(@in, bytes.Length, ref hash1, ref hash2, ref hash3,ref hash4, 0, 0, 0,0);
// }
//}
Stopwatch w = Stopwatch.StartNew();
for (int i = 0; i < 10000000; i++)
{
hash1 = XXHash64.Hash(bytes);
//hash2 = XXHash32.Hash(bytes);
}
w.Stop();
Console.WriteLine($"cost:{w.ElapsedMilliseconds}");
Console.WriteLine(hash1 == hash2);
}
public unsafe static void HashRandomBytesFor()
{
var rd = new Random(Guid.NewGuid().GetHashCode());
ulong hash1 = 0;
for (int n = 1; n <= 8; n++)
{
byte[] bytes = new byte[n];
for (int i = 0; i < bytes.Length; i++)
{
bytes[i] = (byte)rd.Next(0, byte.MaxValue);
}
long costA = 0;
var w = Stopwatch.StartNew();
fixed(byte * @in = &bytes[0])
{
if (n == 1)
{
for (int i = 0; i < 100000000; i++)
{
//hash1 = FastHash.Hash(bytes);
//hash1 = XXHash64.HashUnroll(@in,n,0);
hash1 = XXHash64.Hash1(@in, 0);
}
costA = w.ElapsedMilliseconds;
}
if (n == 2)
{
for (int i = 0; i < 100000000; i++)
{
hash1 = XXHash64.Hash2(@in, 0);
}
costA = w.ElapsedMilliseconds;
}
if (n == 3)
{
for (int i = 0; i < 100000000; i++)
{
hash1 = XXHash64.Hash3(@in, 0);
}
costA = w.ElapsedMilliseconds;
}
if (n == 4)
{
for (int i = 0; i < 100000000; i++)
{
hash1 = XXHash64.Hash4(@in, 0);
}
costA = w.ElapsedMilliseconds;
}
if (n == 5)
{
for (int i = 0; i < 100000000; i++)
{
hash1 = XXHash64.Hash5(@in, 0);
}
costA = w.ElapsedMilliseconds;
}
if (n == 6)
{
for (int i = 0; i < 100000000; i++)
{
hash1 = XXHash64.Hash6(@in, 0);
}
costA = w.ElapsedMilliseconds;
}
if (n == 7)
{
for (int i = 0; i < 100000000; i++)
{
hash1 = XXHash64.Hash7(@in, 0);
}
costA = w.ElapsedMilliseconds;
}
if (n == 8)
{
for (int i = 0; i < 100000000; i++)
{
hash1 = XXHash64.Hash8(@in, 0);
}
costA = w.ElapsedMilliseconds;
}
w = Stopwatch.StartNew();
for (int i = 0; i < 100000000; i++)
{
hash1 = XXHash64.Hash(@in, n, 0);
}
}
w.Stop();
long costB = w.ElapsedMilliseconds;
Console.WriteLine($"Length:{n.ToString().PadRight(3,' ')} " +
$"FastHash Cost:{costA.ToString().PadRight(5, ' ')} " +
$"XXHash64 Cost:{costB.ToString().PadRight(5, ' ')} " +
$"Times:{((float)costB/costA).ToString("f3").PadRight(5,' ')}");
}
//rd = new Random(Guid.NewGuid().GetHashCode());
//for (int n = 1; n <= 32; n++)
//{
// byte[] bytes = new byte[n];
// for (int i = 0; i < bytes.Length; i++)
// bytes[i] = (byte)rd.Next(0, byte.MaxValue);
// Stopwatch w = Stopwatch.StartNew();
// for (int i = 0; i < 100000000; i++)
// {
// hash1 = XXHash64.Hash(bytes);
// }
// w.Stop();
// Console.WriteLine($"length:{n} XXHash64 cost:{w.ElapsedMilliseconds}");
//}
}