Re: [MetaFS-devel] Is this a bug in metafs version 0.1.5?

[Joshua J. B. <de...@co...>]

On Thursday 22 February 2007 18:28:40 汤斯亮 wrote:
> When I was using metafs, I found something a little unusual that may be a
> bug in metafs.

Thanks for your note.  Sorry for not getting back to you sooner.

> In the operation rename, uid changes to root automatically.
>
>  I look over the code in file metafsd/fuse_ll.cc, function "static void
> _rename(fuse_req_t req, fuse_ino_t parent, const char *name, fuse_ino_t
> newparent, const char *newname)", line 503,
> "destdir->rename(&Context::root, srcdir, name, newname);"
>
> Why metafs pass parameter "&Context::root" instead of "&ctx"?

Probably because I wasn't paying attention. ;)  I've pushed a fix for this 
into the Darcs repository.  Thanks for the bug report.

> And in the root-plugin realfs, file plugins/realfs/xattr_db.cc.
>
> When operating Berkeley db, code, such as "if (! strncmp((char
> *)oldvalue.get_data(), name.c_str(), oldvalue.get_size()))", seems not
> work in it's originally intention.
>
> Metafs compares data "oldvalue" and "name", if they have same prefix?
>
> An "oldvalue" "aaa" will not be replaced if "name" string is "aaaaa".
> Should metafs check the string length before comparing?

hmmm, yes.  There was another problem I saw while I was reading through, so 
I reworked that code a bit.  Please try the attached patch and let me know 
if it fixes the problem.

I don't use xattr_db myself anymore, so I don't have any easy way of testing 
it, unfortunately.

Thanks for the feedback!

-- Josh


-- 
Joshua J. Berry

"I haven't lost my mind -- it's backed up on tape somewhere."
    -- /usr/games/fortune