From mboxrd@z Thu Jan  1 00:00:00 1970
To: 9fans@9fans.net
Subject: Re: [9fans] HFS is a pain in the neck.
From: "Russ Cox" <rsc@swtch.com>
Date: Sat, 19 Jul 2008 12:51:27 -0400
In-Reply-To: <f7aa55205f7f4b7036b69d55cbe93553@9srv.net>
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Both the vac file format and p9p can handle files
that Plan 9 cannot.  Other than anti-social characters
in file names, they also handle symbolic links.  There are
people who use vac and p9p but have never used Plan 9.
Imposing Plan 9's restrictions on non-Plan 9 users seems odd
and certainly isn't a way to attract users.

When this came up with u9fs, the solution was to treat
u9fs as the boundary between the cleaner Plan 9 world
and the outside world: it's u9fs's responsibility to keep
the bad names out.  Since the vac format already includes
many hooks to represent Unix and MS-DOS and other kinds
of non-Plan 9 file information, I think of vacfs as straddling
the same boundary that u9fs does.

Especially now that there is an unvac, it seems to me that
the right thing to do is make vacfs skip over the paths that
it cannot reliably report back.  The change is minimal: in
vacfs.c:/^vacdirread, in the for loop, add something like

		if(i == 0)
			break;
+		if(isfrogged(vd.elem)){
+			vdcleanup(&vd);
+			continue;
+		}
		n = vacstat(f->file, &vd, (uchar*)p, cnt-nb);

along with a suitable isfrogged() function and a copy of the
isfrog table from the kernel.

If you were feeling more ambitious, you could use the
defrog and enfrog routines from u9fs to translate the
names into Plan 9-acceptable ones.

Russ