/// <summary>
/// Calculate content hash of content in a stream.
/// </summary>
public static async Task <ContentHash> CalculateHashAsync(this StreamWithLength stream, HashType hashType)
{
using (var hasher = HashInfoLookup.Find(hashType).CreateContentHasher())
{
return(await hasher.GetContentHashAsync(stream));
}
}
/// <summary>
/// Attempt to create from a known type and string (without type).
/// </summary>
public static bool TryParse(HashType hashType, string serialized, out ContentHash contentHash)
{
Contract.Requires(serialized != null);
var hashInfo = HashInfoLookup.Find(hashType);
if (serialized.Length != hashInfo.StringLength)
{
contentHash = default(ContentHash);
return(false);
}
if (!ReadOnlyFixedBytes.TryParse(serialized, out var bytes, out _))
{
contentHash = default(ContentHash);
return(false);
}
contentHash = new ContentHash(hashType, bytes);
if (HashInfoLookup.Find(hashType) is TaggedHashInfo && !AlgorithmIdHelpers.IsHashTagValid(contentHash))
{
contentHash = default(ContentHash);
return(false);
}
return(true);
}
/// <summary>
/// Calculate content hash of content in a byte array.
/// </summary>
public static ContentHash CalculateHash(this byte[] content, HashType hashType)
{
using (var hasher = HashInfoLookup.Find(hashType).CreateContentHasher())
{
return(hasher.GetContentHash(content));
}
}
/// <summary>
/// Initializes a new instance of the <see cref="ContentHash" /> struct from byte array
/// </summary>
public ContentHash(byte[] buffer, int offset = 0, SerializeHashBytesMethod serializeMethod = SerializeHashBytesMethod.Trimmed)
{
Contract.Requires(buffer != null);
_hashType = (HashType)buffer[offset++];
var length = serializeMethod == SerializeHashBytesMethod.Trimmed
? HashInfoLookup.Find(_hashType).ByteLength
: MaxHashByteLength;
_bytes = new ReadOnlyFixedBytes(buffer, length, offset);
}
/// <summary>
/// Create a random value.
/// </summary>
public static ContentHash Random(HashType hashType = HashType.Vso0)
{
var hashInfo = HashInfoLookup.Find(hashType);
var bytes = ThreadSafeRandom.GetBytes(hashInfo.ByteLength);
if (hashInfo is TaggedHashInfo taggedHashInfo)
{
bytes[bytes.Length - 1] = taggedHashInfo.AlgorithmId;
}
return(new ContentHash(hashType, bytes));
}
/// <summary>
/// Calculate content hash of content in a stream.
/// </summary>
public static Task <ContentHash> CalculateHashAsync(this StreamWithLength stream, HashType hashType)
{
#if NET_COREAPP
if (stream.Stream is FileStream fileStream)
{
return(Task.FromResult(fileStream.HashFile(hashType)));
}
#endif // NET_COREAPP
var hasher = HashInfoLookup.GetContentHasher(hashType);
return(hasher.GetContentHashAsync(stream));
}
/// <summary>
/// Initializes a new instance of the <see cref="ContentHash" /> struct from byte array
/// </summary>
public ContentHash(HashType hashType, ReadOnlySpan <byte> buffer, int offset = 0)
{
Contract.Requires(hashType != HashType.Unknown);
int hashBytesLength = HashInfoLookup.Find(hashType).ByteLength;
if (buffer.Length < (hashBytesLength + offset))
{
throw new ArgumentException($"Buffer undersized length=[{buffer.Length}] for hash type=[{hashType}]");
}
_hashType = hashType;
_bytes = new ReadOnlyFixedBytes(buffer, hashBytesLength, offset);
}
/// <summary>
/// Whether <paramref name="contentHash"/> is the empty hash.
/// </summary>
public static bool IsEmptyHash(this ContentHash contentHash)
{
return(contentHash == HashInfoLookup.Find(contentHash.HashType).EmptyHash);
}
public static bool IsZero(this ContentHash contentHash)
{
return(contentHash == HashInfoLookup.Find(contentHash.HashType).Zero);
}
/// <summary>
/// Calculate content hash of content in a stream.
/// </summary>
public static Task <ContentHash> CalculateHashAsync(this StreamWithLength stream, HashType hashType)
{
var hasher = HashInfoLookup.GetContentHasher(hashType);
return(hasher.GetContentHashAsync(stream));
}
/// <summary>
/// Calculate content hash of content in a byte array.
/// </summary>
public static ContentHash CalculateHash(this byte[] content, HashType hashType)
{
return(HashInfoLookup.GetContentHasher(hashType).GetContentHash(content));
}
