dnl Autoconf macros for checking for aggregate type members
dnl
dnl Copyright (C) 1996, 1997, 1998, 2002, 2004, 2005, 2007 Free Software Foundation, Inc.
dnl
dnl Mostly written by Miles Bader <miles@gnu.ai.mit.edu>
dnl
dnl This program is free software; you can redistribute it and/or modify
dnl it under the terms of the GNU General Public License as published by
dnl the Free Software Foundation; either version 3, or (at your option)
dnl any later version.
dnl
dnl This program is distributed in the hope that it will be useful,
dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
dnl GNU General Public License for more details.
dnl
dnl You should have received a copy of the GNU General Public License
dnl along with this program; if not, write to the Free Software
dnl Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
dnl

dnl IU_CHECK_MEMBER(AGGREGATE.MEMBER,
dnl                [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND],
dnl                [INCLUDES])
dnl AGGREGATE.MEMBER is for instance `struct passwd.pw_gecos'.
dnl The member itself can be of an aggregate type
dnl Shell variables are not a valid argument.
AC_DEFUN([IU_CHECK_MEMBER],
[AS_LITERAL_IF([$1], [],
               [AC_FATAL([$0: requires literal arguments])])dnl
m4_bmatch([$1], [\.], ,
         [m4_fatal([$0: Did not see any dot in `$1'])])dnl
AS_VAR_PUSHDEF([ac_Member], [ac_cv_member_$1])dnl
dnl Extract the aggregate name, and the member name
AC_CACHE_CHECK([for $1], ac_Member,
[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([AC_INCLUDES_DEFAULT([$4])],
[dnl AGGREGATE ac_aggr;
static m4_bpatsubst([$1], [\..*]) ac_aggr;
dnl ac_aggr.MEMBER;
if (sizeof(ac_aggr.m4_bpatsubst([$1], [^[^.]*\.])))
return 0;])],
                [AS_VAR_SET(ac_Member, yes)],
                [AS_VAR_SET(ac_Member, no)])])
AS_IF([test AS_VAR_GET(ac_Member) = yes], [$2], [$3])
AS_VAR_POPDEF([ac_Member])dnl
])dnl IU_CHECK_MEMBER

dnl IU_CHECK_MEMBERS([AGGREGATE.MEMBER, ...],
dnl                  [ACTION-IF-FOUND], [ACTION-IF-NOT-FOUND]
dnl                  [INCLUDES])
AC_DEFUN([IU_CHECK_MEMBERS],
[m4_foreach([AC_Member], [$1],
  [IU_CHECK_MEMBER(AC_Member,
         [AC_DEFINE_UNQUOTED(AS_TR_CPP(HAVE_[]AC_Member), 1,
                            [Define to 1 if `]m4_bpatsubst(AC_Member,
                                                     [^[^.]*\.])[' is
                             member of `]m4_bpatsubst(AC_Member, [\..*])['.])
$2],
                 [$3],
                 [$4])])])