warn-on-use: use instead of link-warning Each *.in.h file serves two purposes - provide enough self-contained content to serve as a replacement for the system header regardless of the user's compiler, and offer the developer the ability to detect any gnulib modules that might have been inadvertantly excluded. The former requires independence from config.h, and routes everything through a Makefile.am snippet that uses @@ substitution specific to the modules that were in use, with details learned at configure time. The latter works by poisoning anything that gnulib did not replace, but which the developer had natively available, explaining why their tests passed during development. Poisoning relies on gcc features, and requires manual triggering by adding -DGNULIB_POSIXCHECK to CFLAGS; it assumes that <config.h> is properly included. In fact, we do not want to use @@ substitution for HAVE_DECL_* during poisoning, because the warning is only relevant for the gnulib modules which were not included, and thus where the m4 macros to set proper @@ values have not been run. Furthermore, we only need to poison interfaces that already have a declaration; if something is not declared, then the developer wouldn't have been able to link, so their code won't be using the problematic interface in the first place. * modules/stdio (Depends-on, Makefile.am): Drop link-warning. * modules/unistd (Depends-on, Makefile.am): Likewise. * modules/arpa_inet (Depends-on): Replace link-warning with warn-on-use. (Makefile.am): Update rules accordingly. * modules/ctype (Depends-on, Makefile.am): Likewise. * modules/dirent (Depends-on, Makefile.am): Likewise. * modules/fcntl-h (Depends-on, Makefile.am): Likewise. * modules/inttypes (Depends-on, Makefile.am): Likewise. * modules/langinfo (Depends-on, Makefile.am): Likewise. * modules/locale (Depends-on, Makefile.am): Likewise. * modules/math (Depends-on, Makefile.am): Likewise. * modules/search (Depends-on, Makefile.am): Likewise. * modules/signal (Depends-on, Makefile.am): Likewise. * modules/spawn (Depends-on, Makefile.am): Likewise. * modules/stdlib (Depends-on, Makefile.am): Likewise. * modules/string (Depends-on, Makefile.am): Likewise. * modules/strings (Depends-on, Makefile.am): Likewise. * modules/sys_file (Depends-on, Makefile.am): Likewise. * modules/sys_ioctl (Depends-on, Makefile.am): Likewise. * modules/sys_select (Depends-on, Makefile.am): Likewise. * modules/sys_socket (Depends-on, Makefile.am): Likewise. * modules/sys_stat (Depends-on, Makefile.am): Likewise. * modules/sys_times (Depends-on, Makefile.am): Likewise. * modules/sys_utsname (Depends-on, Makefile.am): Likewise. * modules/wchar (Depends-on, Makefile.am): Likewise. * m4/arpa_inet_h.m4 (gl_HEADER_ARPA_INET): Check which functions should be poisoned. * m4/ctype.m4 (gl_CTYPE_H): Likewise. * m4/dirent_h.m4 (gl_DIRENT_H): Likewise. * m4/fcntl_h.m4 (gl_FCNTL_H): Likewise. * m4/inttypes.m4 (gl_INTTYPES_H): Likewise. * m4/langinfo_h.m4 (gl_LANGINFO_H): Likewise. * m4/locale_h.m4 (gl_LOCALE_H): Likewise. * m4/math_h.m4 (gl_MATH_H): Likewise. * m4/search_h.m4 (gl_SEARCH_H): Likewise. * m4/signal_h.m4 (gl_SIGNAL_H): Likewise. * m4/spawn_h.m4 (gl_SPAWN_H): Likewise. * m4/stdio_h.m4 (gl_STDIO_H): Likewise. * m4/stdlib_h.m4 (gl_STDLIB_H): Likewise. * m4/string_h.m4 (gl_HEADER_STRING_H_BODY): Likewise. * m4/strings_h.m4 (gl_HEADER_STRINGS_H_BODY): Likewise. * m4/sys_file_h.m4 (gl_HEADER_SYS_FILE_H_DEFAULTS): Likewise. * m4/sys_ioctl_h.m4 (gl_SYS_IOCTL_H): Likewise. * m4/sys_select_h.m4 (gl_HEADER_SYS_SELECT): Likewise. * m4/sys_socket_h.m4 (gl_HEADER_SYS_SOCKET): Likewise. * m4/sys_stat_h.m4 (gl_HEADER_SYS_STAT_H): Likewise. * m4/sys_times_h.m4 (gl_SYS_TIMES_H): Likewise. * m4/sys_utsname_h.m4 (gl_SYS_UTSNAME_H): Likewise. * m4/unistd_h.m4 (gl_UNISTD_H): Likewise. * m4/wchar.m4 (gl_WCHAR_H): Likewise. * lib/arpa_inet.in.h: Use _GL_WARN_ON_USE instead of GL_LINK_WARNING. * lib/ctype.in.h: Likewise. * lib/dirent.in.h: Likewise. * lib/fcntl.in.h: Likewise. * lib/inttypes.in.h: Likewise. * lib/langinfo.in.h: Likewise. * lib/locale.in.h: Likewise. * lib/math.in.h: Likewise. * lib/search.in.h: Likewise. * lib/signal.in.h: Likewise. * lib/spawn.in.h: Likewise. * lib/stdio.in.h: Likewise. * lib/stdlib.in.h: Likewise. * lib/string.in.h: Likewise. * lib/strings.in.h: Likewise. * lib/sys_file.in.h: Likewise. * lib/sys_ioctl.in.h: Likewise. * lib/sys_select.in.h: Likewise. * lib/sys_socket.in.h: Likewise. * lib/sys_stat.in.h: Likewise. * lib/sys_times.in.h: Likewise. * lib/sys_utsname.in.h: Likewise. * lib/unistd.in.h: Likewise. * lib/wchar.in.h: Likewise. Signed-off-by: Eric Blake <ebb9@byu.net>

/* Substitute for and wrapper around <sys/ioctl.h>.
   Copyright (C) 2008-2010 Free Software Foundation, Inc.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software Foundation,
   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */

#ifndef _GL_SYS_IOCTL_H

#if __GNUC__ >= 3
@PRAGMA_SYSTEM_HEADER@
#endif

/* The include_next requires a split double-inclusion guard.  */
#if @HAVE_SYS_IOCTL_H@
# @INCLUDE_NEXT@ @NEXT_SYS_IOCTL_H@
#endif

#ifndef _GL_SYS_IOCTL_H
#define _GL_SYS_IOCTL_H

/* AIX 5.1 and Solaris 10 declare ioctl() in <unistd.h> and in <stropts.h>,
   but not in <sys/ioctl.h>.
   But avoid namespace pollution on glibc systems.  */
#ifndef __GLIBC__
# include <unistd.h>
#endif

/* The definition of _GL_WARN_ON_USE is copied here.  */


/* Declare overridden functions.  */

#ifdef __cplusplus
extern "C" {
#endif


#if @GNULIB_IOCTL@
# if @SYS_IOCTL_H_HAVE_WINSOCK2_H@
#  undef ioctl
#  define ioctl rpl_ioctl
extern int ioctl (int fd, int request, ... /* {void *,char *} arg */);
# endif
#elif @SYS_IOCTL_H_HAVE_WINSOCK2_H_AND_USE_SOCKETS@
# undef ioctl
# define ioctl ioctl_used_without_requesting_gnulib_module_ioctl
#elif defined GNULIB_POSIXCHECK
# undef ioctl
# if HAVE_RAW_DECL_IOCTL
_GL_WARN_ON_USE (ioctl, "ioctl does not portably work on sockets - "
                 "use gnulib module ioctl for portability");
# endif
#endif


#ifdef __cplusplus
}
#endif


#endif /* _GL_SYS_IOCTL_H */
#endif /* _GL_SYS_IOCTL_H */