LibUv Networking (#65)

Projects/Server/Buffers/MemoryPoolBlock.cs

@@ -0,0 +1,57 @@
+// Copyright (c) Microsoft. All rights reserved.
+// Licensed under the MIT license. See LICENSE file in the project root for full license information.
+
+using System.Runtime.InteropServices;
+
+namespace System.Buffers
+{
+  /// <summary>
+  /// Block tracking object used by the byte buffer memory pool. A slab is a large allocation which is divided into smaller blocks. The
+  /// individual blocks are then treated as independent array segments.
+  /// </summary>
+  public sealed class MemoryPoolBlock : IMemoryOwner<byte>
+  {
+    private readonly int _offset;
+    private readonly int _length;
+
+    /// <summary>
+    /// This object cannot be instantiated outside of the static Create method
+    /// </summary>
+    internal MemoryPoolBlock(SlabMemoryPool pool, MemoryPoolSlab slab, int offset, int length)
+    {
+      _offset = offset;
+      _length = length;
+
+      Pool = pool;
+      Slab = slab;
+
+      Memory = MemoryMarshal.CreateFromPinnedArray(slab.Array, _offset, _length);
+    }
+
+    /// <summary>
+    /// Back-reference to the memory pool which this block was allocated from. It may only be returned to this pool.
+    /// </summary>
+    public SlabMemoryPool Pool { get; }
+
+    /// <summary>
+    /// Back-reference to the slab from which this block was taken, or null if it is one-time-use memory.
+    /// </summary>
+    public MemoryPoolSlab Slab { get; }
+
+    public Memory<byte> Memory { get; }
+
+    ~MemoryPoolBlock()
+    {
+      Pool.RefreshBlock(Slab, _offset, _length);
+    }
+
+    public void Dispose()
+    {
+      Pool.Return(this);
+    }
+
+    public void Lease()
+    {
+    }
+  }
+}