/// <inheritdoc />
protected override async Task <byte[]> ComputeHashAsyncInternal(IUnifiedDataAsync data, CancellationToken cancellationToken)
{
var prime = _fnvPrimeOffset.Prime;
var offset = _fnvPrimeOffset.Offset;
// Handle 32-bit and 64-bit cases in a strongly-typed manner for performance
if (HashSizeInBits == 32)
{
var hash = offset[0];
await data.ForEachReadAsync(
(dataBytes, position, length) => {
ProcessBytes32(ref hash, prime[0], dataBytes, position, length);
},
cancellationToken)
.ConfigureAwait(false);
return(BitConverter.GetBytes(hash));
}
else if (HashSizeInBits == 64)
{
var hash = ((UInt64)offset[1] << 32) | offset[0];
var prime64 = ((UInt64)prime[1] << 32) | prime[0];
await data.ForEachReadAsync(
(dataBytes, position, length) => {
ProcessBytes64(ref hash, prime64, dataBytes, position, length);
},
cancellationToken)
.ConfigureAwait(false);
return(BitConverter.GetBytes(hash));
}
// Process extended-sized FNV.
{
var hash = offset.ToArray();
await data.ForEachReadAsync(
(dataBytes, position, length) => {
ProcessBytes(ref hash, prime, dataBytes, position, length);
},
cancellationToken)
.ConfigureAwait(false);
return(UInt32ArrayToBytes(hash)
.ToArray());
}
}
protected override async Task <byte[]> ComputeHashAsyncInternal(IUnifiedDataAsync data, CancellationToken cancellationToken)
{
UInt32 h = 0;
await data.ForEachReadAsync(
(dataBytes, position, length) => {
ProcessBytes(ref h, dataBytes, position, length);
},
cancellationToken)
.ConfigureAwait(false);
return(BitConverter.GetBytes(h));
}
/// <inheritdoc />
protected override async Task <byte[]> ComputeHashAsyncInternal(IUnifiedDataAsync data, CancellationToken cancellationToken)
{
var h = new byte[HashSizeInBits / 8];
bool firstByte = true;
await data.ForEachReadAsync(
(dataBytes, position, length) => {
ProcessBytes(ref h, ref firstByte, dataBytes, position, length);
},
cancellationToken)
.ConfigureAwait(false);
return(h);
}
/// <exception cref="System.InvalidOperationException">HashSize set to an invalid value.</exception>
/// <inheritdoc />
protected override async Task <byte[]> ComputeHashAsyncInternal(IUnifiedDataAsync data, CancellationToken cancellationToken)
{
byte[] hash = null;
switch (HashSizeInBits)
{
case 8:
{
byte h = (byte)_config.Seed;
await data.ForEachReadAsync(
(dataBytes, position, length) =>
{
ProcessBytes(ref h, dataBytes, position, length);
},
cancellationToken)
.ConfigureAwait(false);
hash = new byte[] { h };
break;
}
case 16:
{
UInt16 h = (UInt16)_config.Seed;
await data.ForEachReadAsync(
(dataBytes, position, length) =>
{
ProcessBytes(ref h, dataBytes, position, length);
},
cancellationToken)
.ConfigureAwait(false);
hash = BitConverter.GetBytes(h);
break;
}
case 32:
{
UInt32 h = (UInt32)_config.Seed;
await data.ForEachReadAsync(
(dataBytes, position, length) =>
{
ProcessBytes(ref h, dataBytes, position, length);
},
cancellationToken)
.ConfigureAwait(false);
hash = BitConverter.GetBytes(h);
break;
}
case 64:
{
UInt64 h = _config.Seed;
await data.ForEachReadAsync(
(dataBytes, position, length) =>
{
ProcessBytes(ref h, dataBytes, position, length);
},
cancellationToken)
.ConfigureAwait(false);
hash = BitConverter.GetBytes(h);
break;
}
default:
throw new NotImplementedException();
}
return(hash);
}