Re: [PATCH 3/3] mtd-utils: keep xattr support enabled

[Mark Hatle <mark.hatle@windriver.com>]

On 8/25/15 10:27 AM, Patrick Ohly wrote:
> On Tue, 2015-08-25 at 08:26 -0500, Mark Hatle wrote:
>> On 8/25/15 6:46 AM, Patrick Ohly wrote:
>>> On Fri, 2015-08-14 at 11:51 +0100, Burton, Ross wrote:
>>>>
>>>> On 12 August 2015 at 10:33, Patrick Ohly <patrick.ohly@intel.com>
>>>> wrote:
>>>>         > There's a "xattr" DISTRO_FEATURE that should be respected
>>>>         here for
>>>>         > target builds (and explicitly enabled for native I guess).
>>>>         
>>>>         I can add that check, if you want.
>>>>         
>>>>         > Does enabling xattr mean adding build dependencies?
>>>>         
>>>>         No, the conditional code uses lgetxattr and llistxattr, which
>>>>         are in
>>>>         glibc.
>>>>
>>>>
>>>> From five seconds of google it looks like these are in musl and uclibc
>>>> too, so I've merged this  to MUT as-is.
>>>
>>> However, it turned out that the XATTR code also introduces a dependency
>>> on sys/acl.h:
>>>
>>> mkfs.jffs2.c:
>>>
>>> #ifndef WITHOUT_XATTR
>>> #include <sys/xattr.h>
>>> #include <sys/acl.h>
>>> #endif
>>>
>>> sys/acl.h gets provided by acl, so it may or may not work depending on
>>> build order and files on the host.
>>>
>>> I hadn't caught that because I had only looked at library dependencies,
>>> sorry for that.
>>>
>>> What's the right fix? Add the dependency on acl-native in the native
>>> case, disable XATTR support for target builds (same state as before) or
>>> make it somehow depend on both "xattr" and "acl" distro features?
>>>
>>> Or only check for "xattr"? I'm uncertain how the two are related.
>>>
>>
>> Use PACKAGECONFIG, add xattr as a configuration that in turn adds the 'acl' as a
>> dependency.  Then acl-native will automatically be converted from 'acl' if the
>> '-native' version is built.
> 
> I agree, a PACKAGECONFIG sounds like the right approach. However, what
> should the default depend on? The "xattr" or "acl" distro feature? What
> if someone wants xattr, but not acl? Should xattr support in mtd-utils
> be enabled in that case even though it pulls in the acl recipe as
> dependency?
> 

I think that depends entirely on the dependencies in the package.  I've seen a
few things that do acl w/o requiring xattr.. but they're usually linked together.

It sounds like at a minimum xattr should be the PACKAGECONFIG based on the xattr
distro feature.

--Mark