[hfs-user] Map node linkage

Pierre Duhem Pierre Duhem <lsduhem@duhem.com>
Fri, 11 Jun 2004 17:33:47 +0200


I'm still working on my HFS/HFS+ image formatter and I get a problem.

I build a HFS image with about 41000 little files.

The catalog mapping bitmap in the B-tree header overflows at about 6,500
files. The first independent node overflows at about 18,300 and the second at
about 30,400 files.

Therefore, I have following linkage:
0 (header) points to 0x0800
0x0800 points to 0x1770
0x1770 points to 0x26E0

However, when I run fsck_hfs on the CD-ROM I burned from this image, I
get an error message:

Invalid map node linkage
4, 9952

Btw, 9952 is 0x26E0 in decimal, which means that the program is not
happy with my solution, in particular with the last node in the linked

When looking at several volumes formatted and filled on a Macintosh
(Mac OS X 1O.2, if it matters), I see that there is always a totally
empty node (with nothing in it, even in the node header) pointed to by
the last node where the bitmap was used.

Should I also implement this?

Thanks in advance for any clue.

Best Regards
Pierre Duhem
Logiciels & Services Duhem, Paris (France)