Init enter game

KcpSharp/Base/KcpBuffer.cs

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+using System.Diagnostics;
+
+namespace KianaBH.KcpSharp.Base;
+
+internal readonly struct KcpBuffer
+{
+    private readonly object? _owner;
+    private readonly Memory<byte> _memory;
+
+    public ReadOnlyMemory<byte> DataRegion => _memory.Slice(0, Length);
+
+    public int Length { get; }
+
+    private KcpBuffer(object? owner, Memory<byte> memory, int length)
+    {
+        _owner = owner;
+        _memory = memory;
+        Length = length;
+    }
+
+    public static KcpBuffer CreateFromSpan(KcpRentedBuffer buffer, ReadOnlySpan<byte> dataSource)
+    {
+        var memory = buffer.Memory;
+        if (dataSource.Length > memory.Length) ThrowRentedBufferTooSmall();
+        dataSource.CopyTo(memory.Span);
+        return new KcpBuffer(buffer.Owner, memory, dataSource.Length);
+    }
+
+    public KcpBuffer AppendData(ReadOnlySpan<byte> data)
+    {
+        if (Length + data.Length > _memory.Length) ThrowRentedBufferTooSmall();
+        data.CopyTo(_memory.Span.Slice(Length));
+        return new KcpBuffer(_owner, _memory, Length + data.Length);
+    }
+
+    public KcpBuffer Consume(int length)
+    {
+        Debug.Assert((uint)length <= (uint)Length);
+        return new KcpBuffer(_owner, _memory.Slice(length), Length - length);
+    }
+
+    public void Release()
+    {
+        new KcpRentedBuffer(_owner, _memory).Dispose();
+    }
+
+    private static void ThrowRentedBufferTooSmall()
+    {
+        throw new InvalidOperationException("The rented buffer is not large enough to hold the data.");
+    }
+}