Eliminated CancellationToken misuse.

Author: electricessence

ArrayPoolExtensions.cs

@@ -0,0 +1,67 @@
+using System;
+using System.Buffers;
+
+namespace Open.Database.Extensions
+{
+    static class LocalArrayPool<T>
+    {
+        public const int MaxArrayLength = 1024 * 1024;
+        static LocalArrayPool()
+        {
+            Instance = ArrayPool<T>.Create(MaxArrayLength, 4);
+        }
+        public static readonly ArrayPool<T> Instance;
+
+        public static void Rent(
+            int minimumLength,
+            Action<Memory<T>> handler)
+        {
+            if (minimumLength < 0)
+                throw new ArgumentOutOfRangeException(nameof(minimumLength), minimumLength, "Must be at least 0.");
+
+            if (minimumLength > MaxArrayLength)
+            {
+                handler(new T[minimumLength]);
+            }
+            else
+            {
+                var array = Instance.Rent(minimumLength);
+                try
+                {
+                    handler(new Memory<T>(array, 0, minimumLength));
+                }
+                finally
+                {
+                    Instance.Return(array, false);
+                }
+            }
+        }
+
+        public static TResult Rent<TResult>(
+            long minimumLength,
+            bool clearAfter,
+            Func<Memory<T>, TResult> handler)
+        {
+            if (minimumLength < 0)
+                throw new ArgumentOutOfRangeException(nameof(minimumLength), minimumLength, "Must be at least 0.");
+
+            if (minimumLength > MaxArrayLength)
+            {
+                return handler(new T[minimumLength]);
+            }
+            else
+            {
+                var array = Instance.Rent((int)(minimumLength));
+                try
+                {
+                    return handler(array);
+                }
+                finally
+                {
+                    Instance.Return(array, clearAfter);
+                }
+            }
+        }
+    }
+
+}