Messages in this thread |  | | | Subject | Re: PATCH to access old-style FAT fs | | From | OGAWA Hirofumi <> | | Date | Tue, 27 Jan 2004 21:55:34 +0900 |
"H. Peter Anvin" <hpa@zytor.com> writes:
> Followup to: <20040126173949.GA788@frodo.local> > By author: Frodo Looijaard <frodol@dds.nl> > In newsgroup: linux.dev.kernel > > > > Hi folks, > > > > I have created and attached a new version of my old-style FAT filesystem > > patch, this time for the 2.6.0 kernel. It can also be found on > > http://debian.frodo.looijaard.name/. > > > > Some old implementation of the FAT standard mark the end of the > > directory file index by inserting a filename beginning with a byte 00. > > All entries after it should be ignored, even though they are not marked > > as deleted. At least some EPOC releases (an OS used on Psion PDAs, for > > example) still use this policy. > > > > It's not just "old implementations" -- it's the spec. > > After reaching a filename beginning with 00, no further data should be > assumed to be in that filesystem. MS-DOS itself would only do that > when formatting the filesystem, so *all* the subsequent entries would > be assumed to start with 00, but that doesn't really seem to be to > spec.
The new cluster for directory entries must be initialized by 0x00. And, when the directory entry is deleted, the name[0] is updated by 0xe5 not 0x00.
So, if the name[0] is 0x00, it after, all bytes in cluster is 0x00.
The fat driver can stop at name[0] == 0x00, but this is just optimization. The behavior shouldn't change by this. -- OGAWA Hirofumi <hirofumi@mail.parknet.co.jp> - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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