Perform Free only on finalizers

Author: neon-nyan

Utility/DnsARecordResult.cs

@@ -3,6 +3,7 @@
 using System;
 using System.Net;
 using System.Net.Sockets;
+using System.Runtime.CompilerServices;
 using System.Runtime.InteropServices;
 
 namespace Hi3Helper.Plugin.Core.Utility;
@@ -88,29 +89,38 @@ public static IPAddress[] GetIPAddressArray(DnsARecordResult* dnsARecordP)
             DnsARecordResult* next = endResultP->NextResult;
 
             // Convert the struct into IPAddress instance.
-            returnIpAddresses[offset++] = GetIPAddressFromResultAndDispose(endResultP);
+            returnIpAddresses[offset++] = new IPAddress(new ReadOnlySpan<byte>(endResultP->AddressData, endResultP->AddressDataLength));
             endResultP                  = next;
         } while (endResultP != null); // Do the loop if the next entry is not null.
 
         // If done, return the array.
         return returnIpAddresses;
     }
 
-    // ReSharper disable once InconsistentNaming
-    private static IPAddress GetIPAddressFromResultAndDispose(DnsARecordResult* resultP)
+    /// <summary>
+    /// Free the instance of <see cref="DnsARecordResult"/> struct and its entries.
+    /// </summary>
+    /// <param name="resultP">The pointer of the current <see cref="DnsARecordResult"/> entry.</param>
+    /// <param name="isFreeAll">If set to true, the current entry and all its next entries will be freed. Otherwise, just free the current one.</param>
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public static void Free(nint resultP, bool isFreeAll = true)
+        => Free((DnsARecordResult*)resultP, isFreeAll);
+
+    /// <summary>
+    /// Free the instance of <see cref="DnsARecordResult"/> struct and its entries.
+    /// </summary>
+    /// <param name="resultP">The pointer of the current <see cref="DnsARecordResult"/> entry.</param>
+    /// <param name="isFreeAll">If set to true, the current entry and all its next entries will be freed. Otherwise, just free the current one.</param>
+    [MethodImpl(MethodImplOptions.AggressiveInlining)]
+    public static void Free(DnsARecordResult* resultP, bool isFreeAll = true)
     {
-        try
-        {
-            return new IPAddress(new ReadOnlySpan<byte>(resultP->AddressData, resultP->AddressDataLength));
-        }
-        finally
+        do
         {
-            // If the result is not null, free the string and the struct.
-            if (resultP != null)
-            {
-                Mem.Free(resultP);
-            }
-        }
+            DnsARecordResult* nextP = resultP->NextResult;
+            Mem.Free(resultP);
+
+            resultP = nextP;
+        } while (resultP != null && isFreeAll);
     }
 
     /// <summary>

Utility/PluginHttpClientBuilder.cs

@@ -417,9 +417,20 @@ private static async Task<IPAddress[]> GetDnsResolverArrayFromCallbackAsync(stri
 
         // Cast as ComAsyncResult and wait as Task, grab the pointer to the DnsARecordResult entries.
         nint dnsARecordResultP = await comAsyncResultP.AsTask<nint>();
-        // Then call this MF to convert DnsARecordResult* (and also freeing the pointer) into IPAddress[],
-        // then return the IPAddress[] so the socket callback can use it.
-        return DnsARecordResult.GetIPAddressArray(dnsARecordResultP);
+        try
+        {
+            // Then call this MF to convert DnsARecordResult* (and also freeing the pointer) into IPAddress[],
+            // then return the IPAddress[] so the socket callback can use it.
+            return DnsARecordResult.GetIPAddressArray(dnsARecordResultP);
+        }
+        finally
+        {
+            if (dnsARecordResultP != nint.Zero)
+            {
+                // Free the DnsARecordResult pointer only if it's not null.
+                DnsARecordResult.Free(dnsARecordResultP);
+            }
+        }
 
         unsafe nint GetAsyncResultPointer(out VoidCallback cancelTriggerCallback)
         {