YooAsset/Assets/YooAsset/Runtime/xxHash/xxHash64.cs

267 lines
9.2 KiB
C#

// ReSharper disable InconsistentNaming
using System;
using System.Buffers;
using System.Diagnostics;
using System.IO;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Threading;
using System.Threading.Tasks;
namespace Standart.Hash.xxHash
{
public static partial class xxHash64
{
/// <summary>
/// Compute xxHash for the data byte array
/// </summary>
/// <param name="data">The source of data</param>
/// <param name="length">The length of the data for hashing</param>
/// <param name="seed">The seed number</param>
/// <returns>hash</returns>
public static unsafe ulong ComputeHash(byte[] data, int length, ulong seed = 0)
{
Debug.Assert(data != null);
Debug.Assert(length >= 0);
Debug.Assert(length <= data.Length);
fixed (byte* pData = &data[0])
{
return UnsafeComputeHash(pData, length, seed);
}
}
/// <summary>
/// Compute xxHash for the data byte array
/// </summary>
/// <param name="data">The source of data</param>
/// <param name="length">The length of the data for hashing</param>
/// <param name="seed">The seed number</param>
/// <returns>hash</returns>
public static unsafe ulong ComputeHash(byte[] data, int offset, int length, ulong seed = 0)
{
Debug.Assert(data != null);
Debug.Assert(length >= 0);
Debug.Assert(offset < data.Length);
Debug.Assert(length <= data.Length - offset);
fixed (byte* pData = &data[0 + offset])
{
return UnsafeComputeHash(pData, length, seed);
}
}
/// <summary>
/// Compute xxHash for the data byte array
/// </summary>
/// <param name="data">The source of data</param>
/// <param name="seed">The seed number</param>
/// <returns>hash</returns>
public static unsafe ulong ComputeHash(System.ArraySegment<byte> data, ulong seed = 0)
{
Debug.Assert(data != null);
return ComputeHash(data.Array, data.Offset, data.Count, seed);
}
/// <summary>
/// Compute xxHash for the async stream
/// </summary>
/// <param name="stream">The stream of data</param>
/// <param name="bufferSize">The buffer size</param>
/// <param name="seed">The seed number</param>
/// <returns>The hash</returns>
public static async ValueTask<ulong> ComputeHashAsync(Stream stream, int bufferSize = 8192, ulong seed = 0)
{
return await ComputeHashAsync(stream, bufferSize, seed, CancellationToken.None);
}
/// <summary>
/// Compute xxHash for the async stream
/// </summary>
/// <param name="stream">The stream of data</param>
/// <param name="bufferSize">The buffer size</param>
/// <param name="seed">The seed number</param>
/// <param name="cancellationToken">The cancelation token</param>
/// <returns>The hash</returns>
public static async ValueTask<ulong> ComputeHashAsync(Stream stream, int bufferSize, ulong seed,
CancellationToken cancellationToken)
{
Debug.Assert(stream != null);
Debug.Assert(bufferSize > 32);
// Optimizing memory allocation
byte[] buffer = ArrayPool<byte>.Shared.Rent(bufferSize + 32);
int readBytes;
int offset = 0;
long length = 0;
// Prepare the seed vector
ulong v1 = seed + XXH_PRIME64_1 + XXH_PRIME64_2;
ulong v2 = seed + XXH_PRIME64_2;
ulong v3 = seed + 0;
ulong v4 = seed - XXH_PRIME64_1;
try
{
// Read flow of bytes
while ((readBytes =
await stream.ReadAsync(buffer, offset, bufferSize, cancellationToken).ConfigureAwait(false)) > 0)
{
length = length + readBytes;
offset = offset + readBytes;
if (offset < 32) continue;
int r = offset % 32; // remain
int l = offset - r; // length
// Process the next chunk
__inline__XXH64_stream_process(buffer, l, ref v1, ref v2, ref v3, ref v4);
// Put remaining bytes to buffer
Utils.BlockCopy(buffer, l, buffer, 0, r);
offset = r;
}
// Process the final chunk
ulong h64 = __inline__XXH64_stream_finalize(buffer, offset, ref v1, ref v2, ref v3, ref v4, length, seed);
return h64;
}
finally
{
// Free memory
ArrayPool<byte>.Shared.Return(buffer);
}
}
/// <summary>
/// Compute xxHash for the data byte span
/// </summary>
/// <param name="data">The source of data</param>
/// <param name="length">The length of the data for hashing</param>
/// <param name="seed">The seed number</param>
/// <returns>hash</returns>
public static unsafe ulong ComputeHash(Span<byte> data, int length, ulong seed = 0)
{
//Debug.Assert(data != null);
//Debug.Assert(length >= 0);
//Debug.Assert(length <= data.Length);
fixed (byte* pData = &MemoryMarshal.GetReference(data))
{
return UnsafeComputeHash(pData, length, seed);
}
}
/// <summary>
/// Compute xxHash for the data byte span
/// </summary>
/// <param name="data">The source of data</param>
/// <param name="length">The length of the data for hashing</param>
/// <param name="seed">The seed number</param>
/// <returns>hash</returns>
public static unsafe ulong ComputeHash(ReadOnlySpan<byte> data, int length, ulong seed = 0)
{
Debug.Assert(data != null);
Debug.Assert(length >= 0);
Debug.Assert(length <= data.Length);
fixed (byte* pData = &MemoryMarshal.GetReference(data))
{
return UnsafeComputeHash(pData, length, seed);
}
}
/// <summary>
/// Compute xxHash for the stream
/// </summary>
/// <param name="stream">The stream of data</param>
/// <param name="bufferSize">The buffer size</param>
/// <param name="seed">The seed number</param>
/// <returns>The hash</returns>
public static ulong ComputeHash(Stream stream, int bufferSize = 8192, ulong seed = 0)
{
Debug.Assert(stream != null);
Debug.Assert(bufferSize > 32);
// Optimizing memory allocation
byte[] buffer = ArrayPool<byte>.Shared.Rent(bufferSize + 32);
int readBytes;
int offset = 0;
long length = 0;
// Prepare the seed vector
ulong v1 = seed + XXH_PRIME64_1 + XXH_PRIME64_2;
ulong v2 = seed + XXH_PRIME64_2;
ulong v3 = seed + 0;
ulong v4 = seed - XXH_PRIME64_1;
try
{
// Read flow of bytes
while ((readBytes = stream.Read(buffer, offset, bufferSize)) > 0)
{
length = length + readBytes;
offset = offset + readBytes;
if (offset < 32) continue;
int r = offset % 32; // remain
int l = offset - r; // length
// Process the next chunk
__inline__XXH64_stream_process(buffer, l, ref v1, ref v2, ref v3, ref v4);
// Put remaining bytes to buffer
Utils.BlockCopy(buffer, l, buffer, 0, r);
offset = r;
}
// Process the final chunk
ulong h64 = __inline__XXH64_stream_finalize(buffer, offset, ref v1, ref v2, ref v3, ref v4, length, seed);
return h64;
}
finally
{
// Free memory
ArrayPool<byte>.Shared.Return(buffer);
}
}
/// <summary>
/// Compute xxHash for the string
/// </summary>
/// <param name="str">The source of data</param>
/// <param name="seed">The seed number</param>
/// <returns>hash</returns>
public static unsafe ulong ComputeHash(string str, uint seed = 0)
{
Debug.Assert(str != null);
fixed (char* c = str)
{
byte* ptr = (byte*) c;
int length = str.Length * 2;
return UnsafeComputeHash(ptr, length, seed);
}
}
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private static unsafe ulong UnsafeComputeHash(byte* ptr, int length, ulong seed)
{
// Use inlined version
// return XXH64(ptr, length, seed);
return __inline__XXH64(ptr, length, seed);
}
}
}