fifo cache

src/Neo/Cryptography/Crypto.cs

@@ -9,6 +9,7 @@
 // Redistribution and use in source and binary forms with or without
 // modifications are permitted.
 
+using Neo.IO.Caching;
 using System;
 using System.Collections.Generic;
 using System.Runtime.InteropServices;
@@ -100,7 +101,8 @@ public static bool VerifySignature(ReadOnlySpan<byte> message, ReadOnlySpan<byte
             }
         }
 
-        private static readonly Dictionary<ECC.ECPoint, ECDsa> CacheECDsa = new();
+        //private static readonly Dictionary<ECC.ECPoint, ECDsa> CacheECDsa = new();
+        private static readonly ECDsaCache CacheECDsa = new ECDsaCache();
 
         /// <summary>
         /// Create and cache ECDsa objects
@@ -110,9 +112,9 @@ public static bool VerifySignature(ReadOnlySpan<byte> message, ReadOnlySpan<byte
         /// <exception cref="NotSupportedException"></exception>
         public static ECDsa CreateECDsa(ECC.ECPoint pubkey)
         {
-            if (CacheECDsa.TryGetValue(pubkey, out var cache))
+            if (CacheECDsa.TryGet(pubkey, out var cache))
             {
-                return cache;
+                return cache.value;
             }
             ECCurve curve =
                 pubkey.Curve == ECC.ECCurve.Secp256r1 ? ECCurve.NamedCurves.nistP256 :
@@ -128,7 +130,7 @@ public static ECDsa CreateECDsa(ECC.ECPoint pubkey)
                     Y = buffer[33..]
                 }
             });
-            CacheECDsa[pubkey] = ecdsa;
+            CacheECDsa.Add(new ECDsaCacheItem(pubkey, ecdsa));
             return ecdsa;
         }
 

src/Neo/IO/Caching/ECDsaCache.cs

@@ -0,0 +1,32 @@
+// Copyright (C) 2015-2024 The Neo Project.
+//
+// ECDsaCache.cs file belongs to the neo project and is free
+// software distributed under the MIT software license, see the
+// accompanying file LICENSE in the main directory of the
+// repository or http://www.opensource.org/licenses/mit-license.php
+// for more details.
+//
+// Redistribution and use in source and binary forms with or without
+// modifications are permitted.
+
+using Neo.Cryptography.ECC;
+using System;
+using System.Collections.Generic;
+using System.Security.Cryptography;
+using System.Text;
+
+namespace Neo.IO.Caching
+{
+    record ECDsaCacheItem(Cryptography.ECC.ECPoint key, ECDsa value);
+    internal class ECDsaCache : FIFOCache<Cryptography.ECC.ECPoint, ECDsaCacheItem>
+    {
+        public ECDsaCache(int max_capacity = 20000) : base(max_capacity, EqualityComparer<Cryptography.ECC.ECPoint>.Default)
+        {
+        }
+
+        protected override Cryptography.ECC.ECPoint GetKeyForItem(ECDsaCacheItem item)
+        {
+            return item.key;
+        }
+    }
+}