protected void DeleteFile()

in src/log4net/Appender/RollingFileAppender.cs [1177:1229]
42 lines of code
5 McCabe index (conditional complexity)

  protected void DeleteFile(string fileName)
  {
    LogLog.Debug(_declaringType, $"Trying to delete [{fileName}]");

    if (!FileExists(fileName))
    {
      LogLog.Debug(_declaringType, $"[{fileName}] does not exist");
      return;
    }
    // We may not have permission to delete the file, or the file may be locked
    string fileToDelete = fileName;

    // Try to move the file to temp name.
    // If the file is locked we may still be able to move it
    string tempFileName = fileName + "." + Environment.TickCount + ".DeletePending";
    try
    {
      using (SecurityContext?.Impersonate(this))
      {
        System.IO.File.Move(fileName, tempFileName);
      }
      fileToDelete = tempFileName;
    }
    catch (Exception e) when (!e.IsFatal())
    {
      LogLog.Debug(_declaringType, $"Exception while moving file to be deleted [{fileName}] -> [{tempFileName}]", e);
    }

    // Try to delete the file (either the original or the moved file)
    try
    {
      using (SecurityContext?.Impersonate(this))
      {
        System.IO.File.Delete(fileToDelete);
      }
      LogLog.Debug(_declaringType, $"Deleted file [{fileName}]");
    }
    catch (Exception e) when (!e.IsFatal())
    {
      if (fileToDelete == fileName)
      {
        // Unable to move or delete the file
        ErrorHandler.Error($"Exception while deleting file [{fileToDelete}]", e, ErrorCode.GenericFailure);
      }
      else
      {
        // ReSharper disable once GrammarMistakeInComment
        // Moved the file, but the delete failed. File is probably locked.
        // The file should automatically be deleted when the lock is released.
        LogLog.Debug(_declaringType, $"Exception while deleting temp file [{fileToDelete}]", e);
      }
    }
  }