init commit

output/Libraries/BouncyCastle.Crypto/Org/BouncyCastle/Asn1/IndefiniteLengthInputStream.cs

@@ -0,0 +1,82 @@
+using System.IO;
+
+namespace Org.BouncyCastle.Asn1;
+
+internal class IndefiniteLengthInputStream : LimitedInputStream
+{
+	private int _lookAhead;
+
+	private bool _eofOn00 = true;
+
+	internal IndefiniteLengthInputStream(Stream inStream, int limit)
+		: base(inStream, limit)
+	{
+		_lookAhead = RequireByte();
+		CheckForEof();
+	}
+
+	internal void SetEofOn00(bool eofOn00)
+	{
+		_eofOn00 = eofOn00;
+		if (_eofOn00)
+		{
+			CheckForEof();
+		}
+	}
+
+	private bool CheckForEof()
+	{
+		if (_lookAhead == 0)
+		{
+			if (RequireByte() != 0)
+			{
+				throw new IOException("malformed end-of-contents marker");
+			}
+			_lookAhead = -1;
+			SetParentEofDetect(on: true);
+			return true;
+		}
+		return _lookAhead < 0;
+	}
+
+	public override int Read(byte[] buffer, int offset, int count)
+	{
+		if (_eofOn00 || count <= 1)
+		{
+			return base.Read(buffer, offset, count);
+		}
+		if (_lookAhead < 0)
+		{
+			return 0;
+		}
+		int num = _in.Read(buffer, offset + 1, count - 1);
+		if (num <= 0)
+		{
+			throw new EndOfStreamException();
+		}
+		buffer[offset] = (byte)_lookAhead;
+		_lookAhead = RequireByte();
+		return num + 1;
+	}
+
+	public override int ReadByte()
+	{
+		if (_eofOn00 && CheckForEof())
+		{
+			return -1;
+		}
+		int lookAhead = _lookAhead;
+		_lookAhead = RequireByte();
+		return lookAhead;
+	}
+
+	private int RequireByte()
+	{
+		int num = _in.ReadByte();
+		if (num < 0)
+		{
+			throw new EndOfStreamException();
+		}
+		return num;
+	}
+}