Re: New HFS Patch 12.5 fix a dangerous bug

[Sven Luther]

On Thu, Sep 09, 2004 at 03:07:53PM +1000, Stewart Smith wrote:
> On Thu, Sep 09, 2004 at 02:54:29AM +0200, K.G. wrote:
> > The only thing lacking is a complete fs consistency checking tool, but I
> > can still do very usefull checks without it.
> > hpfsck from hfsplusutils does only some basic checks in the volume header.
> > I could port the fsck_hfs tool from apple or write the check fonction for 
> > Parted.
> 
> The OSX fsck is fairly limited as well... but may be good to port (if
> someone hasn't already... i seem to recall something.. somewhere...).
> 
> > I don't think there is a defragmenter in Os X. I think there is an automatic
> > defragmenter in kernel space, but if I remember well it only reduces 
> > internal
> > fragmentation so this won't help. Anyway I'll add a cache that will let find
> > the descriptor of any particular extent in the FS, that will speed things up
> > (should have done it from the very begining but the very begining was a 
> > quick
> > hack to let me install linux in few days on a PPC :p ).
> 
> There is no Apple provided defragmenter in OSX. Although, on open(), if
> a file is less than 20MB and has more than 8 fragments, the FS code will
> try and defragment it. It's pretty easy to see the logic behind this in
> the darwin code. I'll try and find the exact location if you want.
> 
> > > > Of course I'll also try to write working automatic regression tests for 
> > > > HFS
> > > > in next versions. But I must switch to a 2.6 kernel because of HFS bugs 
> > > > in 2.4
> > > > and I still haven't done it for other reasons.
> > > 
> > > You might find user-mode-linux helpful.
> 
> Mac-On-Linux may also be good - as you can then run the OSX utils on the
> same partition (without rebooting).

Altough the the linux MOL drivers have not been ported to 2.6 kernels (or
vice-versa, i am no expert on that).

Friendly,

Sven Luther