fixed CA2002: Do not lock on objects with weak identity - https://learn.microsoft.com/en-us/dotnet/fundamentals/code-analysis/quality-rules/ca2002

Author: FreeAndNil

src/log4net.Tests/Core/FixingTest.cs

@@ -28,6 +28,7 @@
 namespace log4net.Tests.Core;
 
 [TestFixture]
+[System.Diagnostics.CodeAnalysis.SuppressMessage("Usage", "CA2201:Do not raise reserved exception types")]
 public class FixingTest
 {
   const string TestRepository = "Test Repository";

src/log4net/Appender/AppenderSkeleton.cs

@@ -45,16 +45,18 @@ namespace log4net.Appender;
 /// <author>Gert Driesen</author>
 public abstract class AppenderSkeleton : IAppender, IBulkAppender, IOptionHandler, IFlushable
 {
+  /// <summary>
+  /// SyncRoot
+  /// </summary>
+  private protected object SyncRoot { get; } = new();
+
   /// <summary>
   /// Default constructor
   /// </summary>
   /// <remarks>
   /// <para>Empty default constructor</para>
   /// </remarks>
-  protected AppenderSkeleton()
-  {
-    _errorHandler = new OnlyOnceErrorHandler(this.GetType().Name);
-  }
+  protected AppenderSkeleton() => _errorHandler = new OnlyOnceErrorHandler(GetType().Name);
 
   /// <summary>
   /// Finalizes this appender by calling the implementation's 

src/log4net/Appender/BufferingForwardingAppender.cs

@@ -89,23 +89,23 @@ protected override void SendBuffer(LoggingEvent[] events)
   /// Adds an <see cref="IAppender" /> to the list of appenders of this
   /// instance.
   /// </summary>
-  /// <param name="newAppender">The <see cref="IAppender" /> to add to this appender.</param>
+  /// <param name="appender">The <see cref="IAppender" /> to add to this appender.</param>
   /// <remarks>
   /// <para>
   /// If the specified <see cref="IAppender" /> is already in the list of
   /// appenders, then it won't be added again.
   /// </para>
   /// </remarks>
-  public virtual void AddAppender(IAppender newAppender)
+  public virtual void AddAppender(IAppender appender)
   {
-    if (newAppender is null)
+    if (appender is null)
     {
-      throw new ArgumentNullException(nameof(newAppender));
+      throw new ArgumentNullException(nameof(appender));
     }
     lock (LockObj)
     {
       _appenderAttachedImpl ??= new AppenderAttachedImpl();
-      _appenderAttachedImpl.AddAppender(newAppender);
+      _appenderAttachedImpl.AddAppender(appender);
     }
   }
 

src/log4net/Appender/ColoredConsoleAppender.cs

@@ -200,7 +200,7 @@ protected override void Append(LoggingEvent loggingEvent)
     loggingEvent.EnsureNotNull();
     if (_consoleOutputWriter is not null)
     {
-      IntPtr consoleHandle = GetStdHandle(_writeToErrorStream ? StdErrorHandle : StdOutputHandle);
+      IntPtr consoleHandle = NativeMethods.GetStdHandle(_writeToErrorStream ? NativeMethods.StdErrorHandle : NativeMethods.StdOutputHandle);
 
       // Default to white on black
       ushort colorInfo = (ushort)Colors.White;
@@ -215,10 +215,10 @@ protected override void Append(LoggingEvent loggingEvent)
       string strLoggingMessage = RenderLoggingEvent(loggingEvent);
 
       // get the current console color - to restore later
-      GetConsoleScreenBufferInfo(consoleHandle, out ConsoleScreenBufferInfo bufferInfo);
+      NativeMethods.GetConsoleScreenBufferInfo(consoleHandle, out NativeMethods.ConsoleScreenBufferInfo bufferInfo);
 
       // set the console colors
-      SetConsoleTextAttribute(consoleHandle, colorInfo);
+      NativeMethods.SetConsoleTextAttribute(consoleHandle, colorInfo);
 
       // Using WriteConsoleW seems to be unreliable.
       // If a large buffer is written, say 15,000 chars
@@ -315,7 +315,7 @@ protected override void Append(LoggingEvent loggingEvent)
       _consoleOutputWriter.Write(messageCharArray, 0, arrayLength);
 
       // Restore the console back to its previous color scheme
-      SetConsoleTextAttribute(consoleHandle, bufferInfo.wAttributes);
+      NativeMethods.SetConsoleTextAttribute(consoleHandle, bufferInfo.wAttributes);
 
       if (appendNewline)
       {
@@ -344,7 +344,7 @@ public override void ActivateOptions()
     Stream consoleOutputStream = _writeToErrorStream ? Console.OpenStandardError() : Console.OpenStandardOutput();
 
     // Look up the codepage encoding for the console
-    Encoding consoleEncoding = EncodingWithoutPreamble.Get(Encoding.GetEncoding(GetConsoleOutputCP()));
+    Encoding consoleEncoding = EncodingWithoutPreamble.Get(Encoding.GetEncoding(NativeMethods.GetConsoleOutputCP()));
 
     // Create a writer around the console stream
     _consoleOutputWriter = new StreamWriter(consoleOutputStream, consoleEncoding, 0x100)
@@ -391,55 +391,6 @@ public override void ActivateOptions()
   /// </remarks>
   private StreamWriter? _consoleOutputWriter;
 
-  [DllImport("Kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
-  [DefaultDllImportSearchPaths(DllImportSearchPath.System32)]
-  private static extern int GetConsoleOutputCP();
-
-  [DllImport("Kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
-  [DefaultDllImportSearchPaths(DllImportSearchPath.System32)]
-  private static extern bool SetConsoleTextAttribute(
-    IntPtr consoleHandle,
-    ushort attributes);
-
-  [DllImport("Kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
-  [DefaultDllImportSearchPaths(DllImportSearchPath.System32)]
-  private static extern bool GetConsoleScreenBufferInfo(
-    IntPtr consoleHandle,
-    out ConsoleScreenBufferInfo bufferInfo);
-
-  private const uint StdOutputHandle = unchecked((uint)-11);
-  private const uint StdErrorHandle = unchecked((uint)-12);
-
-  [DllImport("Kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
-  [DefaultDllImportSearchPaths(DllImportSearchPath.System32)]
-  private static extern IntPtr GetStdHandle(uint type);
-
-  [StructLayout(LayoutKind.Sequential)]
-  private struct Coord
-  {
-    public ushort x;
-    public ushort y;
-  }
-
-  [StructLayout(LayoutKind.Sequential)]
-  private struct SmallRect
-  {
-    public ushort Left;
-    public ushort Top;
-    public ushort Right;
-    public ushort Bottom;
-  }
-
-  [StructLayout(LayoutKind.Sequential)]
-  private struct ConsoleScreenBufferInfo
-  {
-    public Coord dwSize;
-    public Coord dwCursorPosition;
-    public ushort wAttributes;
-    public SmallRect srWindow;
-    public Coord dwMaximumWindowSize;
-  }
-
   /// <summary>
   /// A class to act as a mapping between the level that a logging call is made at and
   /// the color it should be displayed as.

src/log4net/Appender/FileAppender.cs

@@ -35,8 +35,7 @@ namespace log4net.Appender;
 /// </summary>
 /// <remarks>
 /// <para>
-/// Logging events are sent to the file specified by
-/// the <see cref="File"/> property.
+/// Logging events are sent to the file specified by the <see cref="File"/> property.
 /// </para>
 /// <para>
 /// The file can be opened in either append or overwrite mode 
@@ -90,23 +89,22 @@ private sealed class LockingStream(LockingModelBase lockingModel) : Stream, IDis
     public sealed class LockStateException : LogException
     {
       public LockStateException(string message)
-          : base(message)
-      {
-      }
+        : base(message)
+      { }
 
       public LockStateException()
-      {
-      }
+      { }
 
-      public LockStateException(string message, Exception innerException) : base(message, innerException)
-      {
-      }
+      public LockStateException(string message, Exception innerException)
+        : base(message, innerException)
+      { }
 
-      private LockStateException(SerializationInfo info, StreamingContext context) : base(info, context)
-      {
-      }
+      private LockStateException(SerializationInfo info, StreamingContext context)
+        : base(info, context)
+      { }
     }
 
+    private readonly object syncRoot = new();
     [System.Diagnostics.CodeAnalysis.SuppressMessage("Usage", "CA2213:Disposable fields should be disposed", Justification = "todo")]
     private Stream? _realStream;
     private int _lockLevel;
@@ -173,7 +171,7 @@ private Stream AssertLocked()
     public bool AcquireLock()
     {
       bool ret = false;
-      lock (this)
+      lock (syncRoot)
       {
         if (_lockLevel == 0)
         {
@@ -193,7 +191,7 @@ public bool AcquireLock()
 
     public void ReleaseLock()
     {
-      lock (this)
+      lock (syncRoot)
       {
         _lockLevel--;
         if (_lockLevel == 0)
@@ -843,8 +841,8 @@ public override void OnClose()
   /// Specify default locking model
   /// </summary>
   /// <typeparam name="TLockingModel">Type of LockingModel</typeparam>
-  public static void SetDefaultLockingModelType<TLockingModel>() 
-    where TLockingModel : LockingModelBase 
+  public static void SetDefaultLockingModelType<TLockingModel>()
+    where TLockingModel : LockingModelBase
     => _defaultLockingModelType = typeof(TLockingModel);
 
   /// <summary>
@@ -1215,7 +1213,7 @@ protected virtual void OpenFile(string fileName, bool append)
       }
     }
 
-    lock (this)
+    lock (SyncRoot)
     {
       Reset();
 

src/log4net/Appender/LocalSyslogAppender.cs

@@ -314,7 +314,7 @@ public override void ActivateOptions()
     _handleToIdentity = Marshal.StringToHGlobalAnsi(identString);
 
     // open syslog
-    openlog(_handleToIdentity, 1, Facility);
+    NativeMethods.openlog(_handleToIdentity, 1, Facility);
   }
 
   /// <summary>
@@ -338,7 +338,7 @@ protected override void Append(LoggingEvent loggingEvent)
 
     // Call the local libc syslog method
     // The second argument is a printf style format string
-    syslog(priority, "%s", message);
+    NativeMethods.syslog(priority, "%s", message);
   }
 
   /// <summary>
@@ -357,7 +357,7 @@ protected override void OnClose()
     try
     {
       // close syslog
-      closelog();
+      NativeMethods.closelog();
     }
     catch (DllNotFoundException)
     {
@@ -446,33 +446,6 @@ private static int GeneratePriority(SyslogFacility facility, SyslogSeverity seve
   /// </summary>
   private readonly LevelMapping _levelMapping = new();
 
-  /// <summary>
-  /// Open connection to system logger.
-  /// </summary>
-  [DllImport("libc")]
-  private static extern void openlog(IntPtr ident, int option, SyslogFacility facility);
-
-  /// <summary>
-  /// Generate a log message.
-  /// </summary>
-  /// <remarks>
-  /// <para>
-  /// The libc syslog method takes a format string and a variable argument list similar
-  /// to the classic printf function. As this type of vararg list is not supported
-  /// by C# we need to specify the arguments explicitly. Here we have specified the
-  /// format string with a single message argument. The caller must set the format 
-  /// string to <c>"%s"</c>.
-  /// </para>
-  /// </remarks>
-  [DllImport("libc", CharSet = CharSet.Ansi, CallingConvention = CallingConvention.Cdecl)]
-  private static extern void syslog(int priority, string format, string message);
-
-  /// <summary>
-  /// Close descriptor used to write to system logger.
-  /// </summary>
-  [DllImport("libc")]
-  private static extern void closelog();
-
   /// <summary>
   /// A class to act as a mapping between the level that a logging call is made at and
   /// the syslog severity that is should be logged at.

src/log4net/Appender/OutputDebugStringAppender.cs

@@ -20,6 +20,7 @@
 using System.Runtime.InteropServices;
 
 using log4net.Core;
+using log4net.Util;
 
 namespace log4net.Appender;
 
@@ -45,23 +46,11 @@ protected override void Append(LoggingEvent loggingEvent)
     }
 #endif
 
-    OutputDebugString(RenderLoggingEvent(loggingEvent));
+     NativeMethods.OutputDebugString(RenderLoggingEvent(loggingEvent));
   }
 
   /// <summary>
   /// This appender requires a <see cref="Layout"/> to be set.
   /// </summary>
   protected override bool RequiresLayout => true;
-
-  /// <summary>
-  /// Stub for OutputDebugString native method
-  /// </summary>
-  /// <param name="message">the string to output</param>
-#if NETSTANDARD2_0_OR_GREATER
-  [DllImport("CoreDll.dll")]
-#else
-  [DllImport("Kernel32.dll")]
-#endif
-  [DefaultDllImportSearchPaths(DllImportSearchPath.System32)]
-  protected static extern void OutputDebugString(string message);
 }

src/log4net/Appender/RollingFileAppender.cs

@@ -564,7 +564,7 @@ protected virtual void AdjustFileBeforeAppend()
   /// </remarks>
   protected override void OpenFile(string fileName, bool append)
   {
-    lock (this)
+    lock (SyncRoot)
     {
       fileName = GetNextOutputFileName(fileName);