From edc6504a8478b0596cdad674a64edde138b0dbd9 Mon Sep 17 00:00:00 2001
From: Pavel Djundik <xPaw@users.noreply.github.com>
Date: Sun, 11 Feb 2024 11:47:59 +0200
Subject: [PATCH] Change `KVBinaryBlob` to `Memory<byte>`, faster to string
 conversion

---
 ValveKeyValue/ValveKeyValue/HexStringHelper.cs | 15 +++++++++++++++
 ValveKeyValue/ValveKeyValue/KVBinaryBlob.cs    | 11 +++++++----
 2 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/ValveKeyValue/ValveKeyValue/HexStringHelper.cs b/ValveKeyValue/ValveKeyValue/HexStringHelper.cs
index 0e4f835e..640e49a5 100644
--- a/ValveKeyValue/ValveKeyValue/HexStringHelper.cs
+++ b/ValveKeyValue/ValveKeyValue/HexStringHelper.cs
@@ -1,4 +1,5 @@
 using System.Globalization;
+using System.Runtime.CompilerServices;
 
 namespace ValveKeyValue
 {
@@ -17,5 +18,19 @@ public static byte[] ParseHexStringAsByteArray(string hexadecimalRepresentation)
 
             return data;
         }
+
+        [MethodImpl(MethodImplOptions.AggressiveInlining)]
+        public static char HexToCharUpper(int value)
+        {
+            value &= 0xF;
+            value += '0';
+
+            if (value > '9')
+            {
+                value += ('A' - ('9' + 1));
+            }
+
+            return (char)value;
+        }
     }
 }
diff --git a/ValveKeyValue/ValveKeyValue/KVBinaryBlob.cs b/ValveKeyValue/ValveKeyValue/KVBinaryBlob.cs
index c2956fb9..a3cc7d34 100644
--- a/ValveKeyValue/ValveKeyValue/KVBinaryBlob.cs
+++ b/ValveKeyValue/ValveKeyValue/KVBinaryBlob.cs
@@ -4,7 +4,7 @@ namespace ValveKeyValue
 {
     public class KVBinaryBlob : KVValue
     {
-        public byte[] Bytes { get; }
+        public Memory<byte> Bytes { get; }
 
         public override KVValueType ValueType => KVValueType.BinaryBlob;
 
@@ -102,11 +102,14 @@ public override ulong ToUInt64(IFormatProvider provider)
 
         public override string ToString()
         {
-            var builder = new StringBuilder();
+            var bytes = Bytes.Span;
+            var builder = new StringBuilder(bytes.Length * 3);
 
-            foreach (var oneByte in Bytes)
+            for (var i = 0; i < Bytes.Length; i++)
             {
-                builder.Append(oneByte.ToString("X2"));
+                var b = bytes[i];
+                builder.Append(HexStringHelper.HexToCharUpper(b >> 4));
+                builder.Append(HexStringHelper.HexToCharUpper(b));
                 builder.Append(' ');
             }