Does anyone still need to create legacy HFS filesystems?

[Chris Murphy]

On Feb 3, 2012, at 6:56 AM, Jim Meyering wrote:

> Matthew Garrett wrote:
>> There's various issues with the hfsplus utilities we ship at the moment,
>> including the fact that fsck.hfsplus crashes on 64-bit. I'd like to
> 
> Glad you're looking at this.  I noticed that recently, too.
> I wanted to use fsck.hfsplus in a test to verify that parted's
> newly-revived FS-resizing code produces something reasonable,
> but fsck.hfsplus itself segfaults.

On the issue of HFSJ resizing, I may have found a major discrepancy between reality and Apple's documentation. I'm skeptical that the current resizing code is going to work on large disks at all until it's updated to handle a jhdr_size of 4096 bytes for disks with a 512 byte sector size. Presently the code interprets jhdr_size as the disk's sector size. A difference between the two causes resizing to fail. I'm seeing resizing fail with virtual and real disks of 2TB or greater in size. I do not know what the failure threshold is in terms of volume or disk size, but it appears jhdr_size depends on the size of the volume, not the size of the disk sectors, contrary to Apple's documentation.


http://developer.apple.com/legacy/mac/library/#technotes/tn/tn1150.html

jhdr_size - The size of the journal header, in bytes. The journal header always occupies exactly one sector so that it can be updated atomically. Therefore, this value is equal to the sector size (for example, 2048 on many types of optical media).

Chris Murphy