Use System.Thread.Lock on .NET 9.0

src/Common.AnsiCli/Net/AnsiCliCredentialProvider.cs

@@ -12,7 +12,11 @@ namespace NanoByte.Common.Net;
 /// <param name="beforePrompt">An optional callback to be invoked right before the user is prompted for credentials</param>
 public class AnsiCliCredentialProvider(Action? beforePrompt = null) : ICredentialProvider
 {
+#if NET9_0_OR_GREATER
+    private static readonly Lock _lock = new();
+#else
     private static readonly object _lock = new();
+#endif
 
     /// <inheritdoc/>
     public NetworkCredential GetCredential(Uri uri, bool previousIncorrect = false)

src/Common.AnsiCli/Tasks/AnsiCliTaskHandler.cs

@@ -28,7 +28,11 @@ protected override ICredentialProvider CredentialProvider
                     ? new AnsiCliCredentialProvider(beforePrompt: RemoveProgressBar)
                     : null);
 
-    private readonly object _progressContextLock = new();
+#if NET9_0_OR_GREATER
+    private static readonly Lock _progressContextLock = new();
+#else
+    private static readonly object _progressContextLock = new();
+#endif
     private AnsiCliProgressContext? _progressContext;
 
     /// <inheritdoc/>

src/Common/Log.cs

@@ -52,7 +52,11 @@ public static partial class Log
     /// </summary>
     public static void Error(Exception exception) => AddEntry(LogSeverity.Error, null, exception);
 
+#if NET9_0_OR_GREATER
+    private static readonly Lock _lock = new();
+#else
     private static readonly object _lock = new();
+#endif
 
     /// <summary>
     /// Adds a log entry.

src/Common/Net/WindowsCliCredentialProvider.cs

@@ -14,7 +14,11 @@ namespace NanoByte.Common.Net;
 [SupportedOSPlatform("windows")]
 public class WindowsCliCredentialProvider(Action? beforePrompt = null) : WindowsCredentialProvider
 {
+#if NET9_0_OR_GREATER
+    private static readonly Lock _lock = new();
+#else
     private static readonly object _lock = new();
+#endif
 
     /// <inheritdoc/>
     protected override NetworkCredential GetCredential(string target, WindowsCredentialsFlags flags)

src/Common/Net/WindowsGuiCredentialProvider.cs

@@ -13,7 +13,11 @@ namespace NanoByte.Common.Net;
 [SupportedOSPlatform("windows")]
 public class WindowsGuiCredentialProvider : WindowsCredentialProvider
 {
+#if NET9_0_OR_GREATER
+    private static readonly Lock _lock = new();
+#else
     private static readonly object _lock = new();
+#endif
 
     /// <inheritdoc/>
     protected override NetworkCredential GetCredential(string target, WindowsCredentialsFlags flags)