init commit

output/Libraries/BouncyCastle.Crypto/Org/BouncyCastle/Crypto/Tls/DtlsReassembler.cs

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+using System;
+using System.Collections;
+using Org.BouncyCastle.Utilities;
+
+namespace Org.BouncyCastle.Crypto.Tls;
+
+internal class DtlsReassembler
+{
+	private class Range
+	{
+		private int mStart;
+
+		private int mEnd;
+
+		public int Start
+		{
+			get
+			{
+				return mStart;
+			}
+			set
+			{
+				mStart = value;
+			}
+		}
+
+		public int End
+		{
+			get
+			{
+				return mEnd;
+			}
+			set
+			{
+				mEnd = value;
+			}
+		}
+
+		internal Range(int start, int end)
+		{
+			mStart = start;
+			mEnd = end;
+		}
+	}
+
+	private readonly byte mMsgType;
+
+	private readonly byte[] mBody;
+
+	private readonly IList mMissing = Platform.CreateArrayList();
+
+	internal byte MsgType => mMsgType;
+
+	internal DtlsReassembler(byte msg_type, int length)
+	{
+		mMsgType = msg_type;
+		mBody = new byte[length];
+		mMissing.Add(new Range(0, length));
+	}
+
+	internal byte[] GetBodyIfComplete()
+	{
+		if (mMissing.Count != 0)
+		{
+			return null;
+		}
+		return mBody;
+	}
+
+	internal void ContributeFragment(byte msg_type, int length, byte[] buf, int off, int fragment_offset, int fragment_length)
+	{
+		int num = fragment_offset + fragment_length;
+		if (mMsgType != msg_type || mBody.Length != length || num > length)
+		{
+			return;
+		}
+		if (fragment_length == 0)
+		{
+			if (fragment_offset == 0 && mMissing.Count > 0)
+			{
+				Range range = (Range)mMissing[0];
+				if (range.End == 0)
+				{
+					mMissing.RemoveAt(0);
+				}
+			}
+			return;
+		}
+		for (int i = 0; i < mMissing.Count; i++)
+		{
+			Range range2 = (Range)mMissing[i];
+			if (range2.Start >= num)
+			{
+				break;
+			}
+			if (range2.End <= fragment_offset)
+			{
+				continue;
+			}
+			int num2 = System.Math.Max(range2.Start, fragment_offset);
+			int num3 = System.Math.Min(range2.End, num);
+			int length2 = num3 - num2;
+			Array.Copy(buf, off + num2 - fragment_offset, mBody, num2, length2);
+			if (num2 == range2.Start)
+			{
+				if (num3 == range2.End)
+				{
+					mMissing.RemoveAt(i--);
+				}
+				else
+				{
+					range2.Start = num3;
+				}
+				continue;
+			}
+			if (num3 != range2.End)
+			{
+				mMissing.Insert(++i, new Range(num3, range2.End));
+			}
+			range2.End = num2;
+		}
+	}
+
+	internal void Reset()
+	{
+		mMissing.Clear();
+		mMissing.Add(new Range(0, mBody.Length));
+	}
+}