[PATCH] m4: Check for FTW_ACTIONRETVAL along with nftw

[PATCH] m4: Check for FTW_ACTIONRETVAL along with nftw

[Khem Raj]

FTW_ACTIONRETVAL is glibc specific extention which is used to implement
xfsfind but it may not be available on other C library implementations on Linux
e.g. musl. Therefore ensure that these defines are available before declaring
nftw() to be usable

Signed-off-by: Khem Raj <raj.khem@gmail.com>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: Zorro Lang <zlang@redhat.com>
---
 m4/package_libcdev.m4 | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/m4/package_libcdev.m4 b/m4/package_libcdev.m4
index b41c087b..7f731044 100644
--- a/m4/package_libcdev.m4
+++ b/m4/package_libcdev.m4
@@ -132,7 +132,7 @@ AC_DEFUN([AC_HAVE_NFTW],
 #include <stddef.h>
 #include <ftw.h>
     ]], [[
-         nftw("/", (int (*)(const char *, const struct stat *, int, struct FTW *))1, 0, 0);
+         nftw("/", (int (*)(const char *, const struct stat *, int, struct FTW *))1, 0, FTW_ACTIONRETVAL);
     ]])],[have_nftw=yes
        AC_MSG_RESULT(yes)],[AC_MSG_RESULT(no)])
     AC_SUBST(have_nftw)
-- 
2.40.0

Re: [PATCH] m4: Check for FTW_ACTIONRETVAL along with nftw

[Darrick J. Wong]

On Fri, Mar 24, 2023 at 06:28:58PM -0700, Khem Raj wrote:
> FTW_ACTIONRETVAL is glibc specific extention which is used to implement
> xfsfind but it may not be available on other C library implementations on Linux
> e.g. musl. Therefore ensure that these defines are available before declaring
> nftw() to be usable
> 
> Signed-off-by: Khem Raj <raj.khem@gmail.com>
> Cc: Darrick J. Wong <djwong@kernel.org>
> Cc: Zorro Lang <zlang@redhat.com>
> ---
>  m4/package_libcdev.m4 | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/m4/package_libcdev.m4 b/m4/package_libcdev.m4
> index b41c087b..7f731044 100644
> --- a/m4/package_libcdev.m4
> +++ b/m4/package_libcdev.m4
> @@ -132,7 +132,7 @@ AC_DEFUN([AC_HAVE_NFTW],
>  #include <stddef.h>
>  #include <ftw.h>
>      ]], [[
> -         nftw("/", (int (*)(const char *, const struct stat *, int, struct FTW *))1, 0, 0);
> +         nftw("/", (int (*)(const char *, const struct stat *, int, struct FTW *))1, 0, FTW_ACTIONRETVAL);

Seems fine, though xfsfind.c only uses FTW_CONTINUE and FTW_STOP, so
perhaps it'd better to modify the program not to use FTW_ACTIONRETVAL?

OTOH I'm not /that/ keen on using fuzzing xfs from musl so I'll add this
to my backlog and in the meantime

Looks good to me,
Acked-by: Darrick J. Wong <djwong@kernel.org>

--D

>      ]])],[have_nftw=yes
>         AC_MSG_RESULT(yes)],[AC_MSG_RESULT(no)])
>      AC_SUBST(have_nftw)
> -- 
> 2.40.0
>