On Wed, 2018-10-31 at 08:09 -0700, Stephen Hemminger wrote:

On Mon, 29 Oct 2018 10:46:50 +0000
Luca Boccassi [off-list ref] wrote:

quoted

If libc does not provide strlcpy check for libbsd with pkg-config
to
avoid relying on inline version.

Signed-off-by: Luca Boccassi <redacted>
---
This allows distro maintainers to be able to choose to reduce
duplication and let this code be maintained in one place, in the
external library.

I like the idea, but it causes warnings on Debian testing, and maybe
other distros.

ipnetns.c:2: warning: "_ATFILE_SOURCE" redefined
 #define _ATFILE_SOURCE
 
In file included from /usr/include/x86_64-linux-gnu/bits/libc-header-
start.h:33,
                 from /usr/include/string.h:26,
                 from /usr/include/bsd/string.h:30,
                 from <command-line>:
/usr/include/features.h:326: note: this is the location of the
previous definition
 # define _ATFILE_SOURCE 1


Please figure out how to handle this and resubmit.  SUSE open build
service might
also work to test multiple distro's

Ah missed that. That happens because features.h defines _ATFILE_SOURCE
to 1, but ip/ipnetns.c defines it without a value. According to the
spec either way doesn't change the result.

This happens because of the quick hack of using -include
/usr/include/bsd/string.h which was, well, a quick hack and didn't
require to add the include manually everywhere strlcpy was used, even
in the future. But it has side effects like this.

So I'll send v2 with a less hacky fix, which means defining HAVE_LIBBSD
in configure and doing #ifdef HAVE_LIBBSD #include <bsd/string.h> in
every file. It also means that this needs to be done for every future
use of strlcpy, or the build with libbsd will break.

If you or David prefer the hacky way, I can instead send a v3 that does
the quick hack, and also changes _ATFILE_SOURCE to 1 so that there is
no complaint from the compiler, as the values will be the same.

-- 
Kind regards,
Luca Boccassi