[LTP] [PATCH] tst_device: use raw syscall in the tst_device.h

[Cyril Hrubis]

Hi!
> > But shouldn't we define the _GNU_SOURCE for syscall()?  Otherwise,
> > the _XOPEN_SOURCE 600 definitions will take effect and makes the compiler
> > print new errors[1].
> Correct, syscall() requires _GNU_SOURCE and <unistd.h>.

Not really, it's guarded by _USE_MISC which is enabled by default and
disabled by _XOPEN_SOURCE.

Looks like the manual page is outdated at least.

> + Not sure if <sys/syscall.h> should be used (as it's in your patch or
> lapi/syscalls.h.

Well, given that syncfs is old enough (2.6.39) either should work.

> > Here I feel a little confused, or do we need to delete the _XOPEN_SOURCE
> > definition directly for the test posix_fadvise01.c?
> 
> > [1]:
> > gcc -Werror=implicit-function-declaration -g -O2 -fno-strict-aliasing -pipe
> > -Wall -W -Wold-style-definition
> >  -I/root/ltp2/testcases/kernel/syscalls/fadvise
> > -I/root/ltp2/testcases/kernel/syscalls/fadvise/../utils
> > -I../../../../include -I../../../../include -I../../../../include/old/
> > -L../../../../lib  posix_fadvise01.c   -lltp -o posix_fadvise01
> > In file included from ../../../../include/tst_test.h:22,
> >                  from posix_fadvise01.c:31:
> > ../../../../include/tst_device.h: In function ???tst_dev_sync???:
> > ../../../../include/tst_device.h:82:9: error: implicit declaration of
> > function ???syscall???; did you mean ???strcoll????
> > [-Werror=implicit-function-declaration]
> >   return syscall(__NR_syncfs, fd);
> >          ^~~~~~~
> >          strcoll
> 
> + Our syscall numbers in include/lapi/syscalls/ are outdated (syncfs is not at
> least in include/lapi/syscalls/sparc{64,}.in and
> include/lapi/syscalls/x86_64.in).

The lapi/syscall.h includes sys/syscall.h so it's probably not a
problem, since there are no distribution that are missing syncfs in the
system headers. Note that we are only adding fallback definitions there
and if present the system values take precedence.

-- 
Cyril Hrubis
chrubis@suse.cz