I need some help with extending the VFS for my project. I need hardlink support, so I added the following to repos/os/include/vfs/directory_service.h's Directory_service struct:

    virtual int hardlink(char const *path, char const *hardlink_path)

    {

        (void) path;

        (void)hardlink_path;

        Genode::error("not implemented!");

        return 0;

    }

I have the Lwext4 plugin (https://codeberg.org/jws/genode-wundertuete/src/branch/import-lwext4_from_world-2024-04-19) setup for my project so I then extended repos/wundertuete/src/lib/vfs/lwext4/vfs.cc's Lwext4_vfs_file_system struct:

    int hardlink(char const *path, char const *hardlink_path) override 

    {

        return ext4_flink(path, hardlink_path);

    }

The problem is that hardlink uses the default implementation in my main code:
squidutils->_vfs_env.root_dir().hardlink(p2.string(), p1.string());  // Prints 'not implemented'

From what I have read online the issue is that squidutils->_vfs_env.root_dir() is of type Directory_service, whereas I need it to be Lwext4_vfs_file_system. However, Lwext4_vfs_file_system is declared in the vfs.cc file above as opposed to being declared in a header.

Is there a way to use Lwext4_vfs_file_system without copying the entire source of Lwext4 into my project's source code? Or am I perhaps going in the wrong direction with all of this?

Best,
Rumen