Re: [ANNOUNCE, DISCUSS] xfsprogs: libxfs-4.1-update branch created

From: Eric Sandeen <sandeen@sandeen.net>
To: Dave Chinner <david@fromorbit.com>, xfs@oss.sgi.com
Subject: Re: [ANNOUNCE, DISCUSS] xfsprogs: libxfs-4.1-update branch created
Date: Wed, 13 May 2015 17:14:42 -0500	[thread overview]
Message-ID: <5553CCD2.1010906@sandeen.net> (raw)
In-Reply-To: <20150511000508.GD16689@dastard>

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

One interesting problem that arises from this is in xfs_format.h:

/* On-disk XFS extended attribute names */
#define SGI_ACL_FILE            (char *)"SGI_ACL_FILE"
#define SGI_ACL_DEFAULT         (char *)"SGI_ACL_DEFAULT"
#define SGI_ACL_FILE_SIZE       (sizeof(SGI_ACL_FILE)-1)
#define SGI_ACL_DEFAULT_SIZE    (sizeof(SGI_ACL_DEFAULT)-1)

(aside: why is it unsigned in the kernel but not here?)

Anyway: that "sizeof" gives us 7, because it's getting the 
size of the pointer, not the string literal.  Cool eh!
Never mattered in the kernel, because the _SIZE macros aren't
used.

I'm not actually sure what the cleanest way to fix this is;
casting string literals gets way past my comfort level with 
C pedantry; technically if we want an array of unsigned chars,
we probably need:

unsigned char *SGI_ACL_FILE[] = "SGI_ACL_FILE";
unsigned char *SGI_ACL_DEFAULT[] = "SGI_ACL_DEFAULT";

but then it can't live in the format header; in kernelspace we need that
symbol in xfs_acl.c, in userspace we need it in repair/attr_repair.c 

- -Eric
-----BEGIN PGP SIGNATURE-----
Version: GnuPG/MacGPG2 v2.0.17 (Darwin)
Comment: GPGTools - http://gpgtools.org
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=T5wD
-----END PGP SIGNATURE-----

_______________________________________________
xfs mailing list
xfs@oss.sgi.com
http://oss.sgi.com/mailman/listinfo/xfs