private void ExtractEntry()

in src/ICSharpCode.SharpZipLib/Tar/TarArchive.cs [645:710]
54 lines of code
10 McCabe index (conditional complexity)

		private void ExtractEntry(string destDir, TarEntry entry, bool allowParentTraversal)
		{
			OnProgressMessageEvent(entry, null);

			string name = entry.Name;

			if (Path.IsPathRooted(name))
			{
				// NOTE:
				// for UNC names...  \\machine\share\zoom\beet.txt gives \zoom\beet.txt
				name = name.Substring(Path.GetPathRoot(name).Length);
			}

			name = name.Replace('/', Path.DirectorySeparatorChar);

			string destFile = Path.Combine(destDir, name);
			var destFileDir = Path.GetDirectoryName(Path.GetFullPath(destFile)) ?? "";

			if (!allowParentTraversal && !destFileDir.StartsWith(destDir, StringComparison.InvariantCultureIgnoreCase))
			{
				throw new InvalidNameException("Parent traversal in paths is not allowed");
			}

			if (entry.IsDirectory)
			{
				EnsureDirectoryExists(destFile);
			}
			else
			{
				string parentDirectory = Path.GetDirectoryName(destFile);
				EnsureDirectoryExists(parentDirectory);

				bool process = true;
				var fileInfo = new FileInfo(destFile);
				if (fileInfo.Exists)
				{
					if (keepOldFiles)
					{
						OnProgressMessageEvent(entry, "Destination file already exists");
						process = false;
					}
					else if ((fileInfo.Attributes & FileAttributes.ReadOnly) != 0)
					{
						OnProgressMessageEvent(entry, "Destination file already exists, and is read-only");
						process = false;
					}
				}

				if (process)
				{
					using (var outputStream = File.Create(destFile))
					{
						if (this.asciiTranslate)
						{
							// May need to translate the file.
							ExtractAndTranslateEntry(destFile, outputStream);
						}
						else
						{
							// If translation is disabled, just copy the entry across directly.
							tarIn.CopyEntryContents(outputStream);
						}
					}
				}
			}
		}