init commit

output/Libraries/BouncyCastle.Crypto/Org/BouncyCastle/Utilities/Date/DateTimeUtilities.cs

@@ -0,0 +1,35 @@
+using System;
+
+namespace Org.BouncyCastle.Utilities.Date;
+
+public class DateTimeUtilities
+{
+	public static readonly DateTime UnixEpoch = new DateTime(1970, 1, 1);
+
+	private DateTimeUtilities()
+	{
+	}
+
+	public static long DateTimeToUnixMs(DateTime dateTime)
+	{
+		if (dateTime.CompareTo((object?)UnixEpoch) < 0)
+		{
+			throw new ArgumentException("DateTime value may not be before the epoch", "dateTime");
+		}
+		long ticks = dateTime.Ticks;
+		DateTime unixEpoch = UnixEpoch;
+		return (ticks - unixEpoch.Ticks) / 10000;
+	}
+
+	public static DateTime UnixMsToDateTime(long unixMs)
+	{
+		long num = unixMs * 10000;
+		DateTime unixEpoch = UnixEpoch;
+		return new DateTime(num + unixEpoch.Ticks);
+	}
+
+	public static long CurrentUnixMs()
+	{
+		return DateTimeToUnixMs(DateTime.UtcNow);
+	}
+}