Lucene.Net.Store.NativeFSLock.Obtain C# (CSharp) Method

        public override bool Obtain()
        {
            lock (this)
            {
                FailureReason = null;

                if (Channel != null)
                {
                    // Our instance is already locked:
                    return false;
                }

                if (!System.IO.Directory.Exists(LockDir.FullName))
                {
                    try
                    {
                        System.IO.Directory.CreateDirectory(LockDir.FullName);
                    }
                    catch
                    {
                        throw new System.IO.IOException("Cannot create directory: " + LockDir.FullName);
                    }
                }
                else if (File.Exists(LockDir.FullName))
                {
                    throw new IOException("Found regular file where directory expected: " + LockDir.FullName);
                }

                var success = false;
                try
                {
                    Channel = new FileStream(Path.FullName, FileMode.Create, FileAccess.Write, FileShare.None);
                    Channel.Lock(0, Channel.Length);
                    success = true;
                }
                catch (IOException e)
                {
                    FailureReason = e;
                    IOUtils.CloseWhileHandlingException(Channel);
                    Channel = null;
                }
                // LUCENENET: UnauthorizedAccessException does not derive from IOException like in java
                catch (UnauthorizedAccessException e)
                {
                    // On Windows, we can get intermittent "Access
                    // Denied" here.  So, we treat this as failure to
                    // acquire the lock, but, store the reason in case
                    // there is in fact a real error case.
                    FailureReason = e;
                    IOUtils.CloseWhileHandlingException(Channel);
                    Channel = null;
                }
                finally
                {
                    if (!success)
                    {
                        IOUtils.CloseWhileHandlingException(Channel);
                        Channel = null;
                    }
                }

                return Channel != null;
            }
        }