public static async Task<ObjectWriteResult> CreateTempFile(ObjectType type, int length, byte[] data, string rootPath)
{
var name = Path.Combine(rootPath, "tmp" + _random.Next(0, int.MaxValue));
using (var file = File.OpenWrite(name))
using (var stream = CompressionStream.CompressStream(file))
using (var md = new MessageDigest())
{
var header = Encoding.ASCII.GetBytes(string.Format("{0} {1}\0", type.ToTypeCode(), length));
await stream.WriteAsync(header, 0, header.Length);
await stream.WriteAsync(data, 0, data.Length);
md.Update(header);
md.Update(data);
var digest = md.Digest();
return new ObjectWriteResult
{
FileInfo = new FileInfo(name),
ObjectId = Helper.ByteArrayToId(digest)
};
}
}
/// <summary>
/// Gets the result of a calculation that has a simple input.
/// </summary>
/// <param name="input">The input.</param>
/// <returns></returns>
public static byte[] Digest(byte[] input)
{
using (var me = new MessageDigest())
{
me.Update(input);
return me.Digest();
}
}
public static string ComputeId(Blob blob)
{
using (var md = new MessageDigest())
{
byte[] data = Encoding.Default.GetBytes(string.Format("blob {0}\0", blob.Size));
md.Update(data);
md.Update(blob.Data);
var digest = md.Digest();
return Helper.ByteArrayToId(digest);
}
}