Error scenarios to fix:

1. Creating directory with name longer than 255 characters does not rise an error. The error (enametoolong) occurs when user want to upload a file to such directory, which may be confusing.
2. Creating a directory with name equal to null character can be done, but creating a file inside it throws error eisdir.
3. Renaming a file to name containing only null characters raises enotdir error. After that, file is successfully renamed, but is not downloadable via browser. Renaming it back to a normal name fixes download issue.