1 files changed, 137 insertions, 0 deletions
diff --git a/ThirdParty/CsvHelper-master/src/CsvHelper/FieldCache.cs b/ThirdParty/CsvHelper-master/src/CsvHelper/FieldCache.cs
new file mode 100644
index 0000000..665a650
--- /dev/null
+++ b/ThirdParty/CsvHelper-master/src/CsvHelper/FieldCache.cs
@@ -0,0 +1,137 @@
+// Copyright 2009-2022 Josh Close
+// This file is a part of CsvHelper and is dual licensed under MS-PL and Apache 2.0.
+// See LICENSE.txt for details or visit http://www.opensource.org/licenses/ms-pl.html for MS-PL and http://opensource.org/licenses/Apache-2.0 for Apache 2.0.
+// https://github.com/JoshClose/CsvHelper
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Linq;
+using System.Runtime.CompilerServices;
+using System.Text;
+using System.Threading.Tasks;
+
+// https://blog.markvincze.com/back-to-basics-dictionary-part-2-net-implementation/
+
+namespace CsvHelper
+{
+	/// <summary>
+	/// Caches fields.
+	/// Based on C#'s <see cref="Dictionary{TKey, TValue}"/>.
+	/// </summary>
+	internal class FieldCache
+	{
+		private readonly int maxFieldSize;
+		private int size;
+		private int[] buckets;
+		private Entry[] entries;
+		private int count;
+
+		public FieldCache(int initialSize = 128, int maxFieldSize = 128)
+		{
+			this.maxFieldSize = maxFieldSize;
+			size = initialSize;
+			buckets = new int[size];
+			entries = new Entry[size];
+		}
+
+		public string GetField(char[] buffer, int start, int length)
+		{
+			if (length == 0)
+			{
+				return string.Empty;
+			}
+
+			if (length > maxFieldSize)
+			{
+				return new string(buffer, start, length);
+			}
+
+			var hashCode = GetHashCode(buffer, start, length);
+			ref var bucket = ref GetBucket(hashCode);
+			int i = bucket - 1;
+			while ((uint)i < (uint)entries.Length)
+			{
+				ref var entry = ref entries[i];
+
+				if (entry.HashCode == hashCode && entry.Value.AsSpan().SequenceEqual(new Span<char>(buffer, start, length)))
+				{
+					return entry.Value;
+				}
+
+				i = entry.Next;
+			}
+
+			if (count == entries.Length)
+			{
+				Resize();
+				bucket = ref GetBucket(hashCode);
+			}
+
+			ref var reference = ref entries[count];
+			reference.HashCode = hashCode;
+			reference.Next = bucket - 1;
+			reference.Value = new string(buffer, start, length);
+			bucket = count + 1;
+			count++;
+
+			return reference.Value;
+		}
+
+		[MethodImpl(MethodImplOptions.AggressiveInlining)]
+		private uint GetHashCode(char[] buffer, int start, int length)
+		{
+			unchecked
+			{
+				uint hash = 17;
+				for (var i = start; i < start + length; i++)
+				{
+					hash = hash * 31 + buffer[i];
+				}
+
+				return hash;
+			}
+		}
+
+		[MethodImpl(MethodImplOptions.AggressiveInlining)]
+		private ref int GetBucket(uint hashCode)
+		{
+			return ref buckets[hashCode & buckets.Length - 1];
+		}
+
+		[MethodImpl(MethodImplOptions.AggressiveInlining)]
+		private void Resize()
+		{
+			size *= 2;
+
+			var tempEntries = new Entry[size];
+
+			Array.Copy(entries, tempEntries, count);
+
+			buckets = new int[size];
+
+			for (int i = 0; i < count; i++)
+			{
+				ref var tempEntry = ref tempEntries[i];
+
+				if (tempEntry.Next >= -1)
+				{
+					ref var bucket = ref GetBucket(tempEntry.HashCode);
+					tempEntry.Next = bucket - 1;
+					bucket = i + 1;
+				}
+			}
+
+			entries = tempEntries;
+		}
+
+		[DebuggerDisplay("HashCode = {HashCode}, Next = {Next}, Value = {Value}")]
+		private struct Entry
+		{
+			public uint HashCode;
+
+			public int Next;
+
+			public string Value;
+		}
+	}
+}