grub-0.97/VFS

grub-0.97/VFS

[Edward Shishkin]

Hello everyone.

Grub-0.97 filesystem interface (read_func, dir_func)
seems to be poor. Instead of this I would prefer to
have something like the following:

/*
 *
 * .init_root()           // set index of root dir
 * .lookup_begin()        // get index by name
 * .lookup_end()          // get inode by index
 * .read_file()
 * .read_dir()
 * .read_symlink()
 *
 * so that dir_func in grub_open will look like the
 * following:
 */
int path_walk()
{
    ops->init_root();
    while (1) {
        int mode;
        ops->lookup_end(&mode, ...);

        switch (type_of_file(mode)) {
        case SYMLINK_FILE:
            follow_symlink(read_symlink, ...);
            ...;
            continue;
        case REGULAR_FILE:
            /*
             * the end of path walk:
             * normally we want to exit here
             */
            ...;
            return 1;
        case DIRECTORY_FILE:
            /*
             * optionally this will
             * print possibilities
             */
            ops->lookup_begin(mode, read_dir, ...);
            ...;
            continue;
        default:
            errnum = ERR_BAD_FILETYPE;
            return 0;
        }
    }
}

Just my 2 cents in the (grub-2?) development process..

Thanks,
Edward.

grub-0.97/VFS

[Edward Shishkin]

(CC linux-btrfs mailing list)

Hello everyone.

Grub-0.97 filesystem interface (read_func, dir_func)
seems to be poor. Instead of this I would prefer to
have something like the following:

/*
*
* .init_root()           // set index of root dir
* .lookup_begin()        // get index by name
* .lookup_end()          // get inode by index
* .read_file()
* .read_dir()
* .read_symlink()
*
* so that dir_func in grub_open will look like the
* following:
*/
int path_walk()
{
    ops->init_root();
    while (1) {
        int mode;
        ops->lookup_end(&mode, ...);

        switch (type_of_file(mode)) {
        case SYMLINK_FILE:
            follow_symlink(read_symlink, ...);
            ...;
            continue;
        case REGULAR_FILE:
            /*
             * the end of path walk:
             * normally we want to exit here
             */
            ...;
            return 1;
        case DIRECTORY_FILE:
            /*
             * optionally this will
             * print possibilities
             */
            ops->lookup_begin(mode, read_dir, ...);
            ...;
            continue;
        default:
            errnum = ERR_BAD_FILETYPE;
            return 0;
        }
    }
}

Just my 2 cents in the (grub-2?) development process..

Thanks,
Edward.

Re: grub-0.97/VFS

[Vladimir 'phcoder' Serbinenko]

On Wed, Jul 22, 2009 at 6:41 PM, Edward Shishkin<edward@redhat.com> wrote:
> (CC linux-btrfs mailing list)
>
> Hello everyone.
>
> Grub-0.97 filesystem interface (read_func, dir_func)
> seems to be poor. Instead of this I would prefer to
> have something like the following:
>
Could you have a look at fs/fshelp.c? It's a generic module of library
functions used by other filesystems and is somewhat similar to what
you describe

-- 
Regards
Vladimir 'phcoder' Serbinenko

Personal git repository: http://repo.or.cz/w/grub2/phcoder.git