dnl
dnl Author: Thomas E. Dickey
dnl
-dnl $Id: aclocal.m4,v 1.141 2018/12/15 19:54:31 tom Exp $
+dnl $Id: aclocal.m4,v 1.142 2019/01/01 01:46:17 tom Exp $
dnl Macros used in NCURSES Ada95 auto-configuration script.
dnl
dnl These macros are maintained separately from NCURSES. The copyright on
AC_SUBST(PKG_CONFIG)
])dnl
dnl ---------------------------------------------------------------------------
-dnl CF_POSIX_C_SOURCE version: 10 updated: 2018/06/20 20:23:13
+dnl CF_POSIX_C_SOURCE version: 11 updated: 2018/12/31 20:46:17
dnl -----------------
dnl Define _POSIX_C_SOURCE to the given level, and _POSIX_SOURCE if needed.
dnl
dnl Parameters:
dnl $1 is the nominal value for _POSIX_C_SOURCE
AC_DEFUN([CF_POSIX_C_SOURCE],
-[
+[AC_REQUIRE([CF_POSIX_VISIBLE])dnl
+
+if test "$cf_cv_posix_visible" = no; then
+
cf_POSIX_C_SOURCE=ifelse([$1],,199506L,[$1])
cf_save_CFLAGS="$CFLAGS"
CF_ADD_CFLAGS($cf_cv_posix_c_source)
fi
+fi # cf_cv_posix_visible
+
+])dnl
+dnl ---------------------------------------------------------------------------
+dnl CF_POSIX_VISIBLE version: 1 updated: 2018/12/31 20:46:17
+dnl ----------------
+dnl POSIX documents test-macros which an application may set before any system
+dnl headers are included to make features available.
+dnl
+dnl Some BSD platforms (originally FreeBSD, but copied by a few others)
+dnl diverged from POSIX in 2002 by setting symbols which make all of the most
+dnl recent features visible in the system header files unless the application
+dnl overrides the corresponding test-macros. Doing that introduces portability
+dnl problems.
+dnl
+dnl This macro makes a special check for the symbols used for this, to avoid a
+dnl conflicting definition.
+AC_DEFUN([CF_POSIX_VISIBLE],
+[
+AC_CACHE_CHECK(if the POSIX test-macros are already defined,cf_cv_posix_visible,[
+AC_TRY_COMPILE([#include <stdio.h>],[
+#if defined(__POSIX_VISIBLE) && ((__POSIX_VISIBLE - 0L) > 0) \
+ && defined(__XSI_VISIBLE) && ((__XSI_VISIBLE - 0L) > 0) \
+ && defined(__BSD_VISIBLE) && ((__BSD_VISIBLE - 0L) > 0) \
+ && defined(__ISO_C_VISIBLE) && ((__ISO_C_VISIBLE - 0L) > 0)
+#error conflicting symbols found
+#endif
+],[cf_cv_posix_visible=no],[cf_cv_posix_visible=yes])
+])
])dnl
dnl ---------------------------------------------------------------------------
dnl CF_PROG_AR version: 1 updated: 2009/01/01 20:15:22
])
])dnl
dnl ---------------------------------------------------------------------------
-dnl CF_XOPEN_SOURCE version: 54 updated: 2018/11/07 07:43:44
+dnl CF_XOPEN_SOURCE version: 55 updated: 2018/12/31 20:46:17
dnl ---------------
dnl Try to get _XOPEN_SOURCE defined properly that we can use POSIX functions,
dnl or adapt to the vendor's definitions to get equivalent functionality,
dnl $2 is the nominal value for _POSIX_C_SOURCE
AC_DEFUN([CF_XOPEN_SOURCE],[
AC_REQUIRE([AC_CANONICAL_HOST])
+AC_REQUIRE([CF_POSIX_VISIBLE])
+
+if test "$cf_cv_posix_visible" = no; then
cf_XOPEN_SOURCE=ifelse([$1],,500,[$1])
cf_POSIX_C_SOURCE=ifelse([$2],,199506L,[$2])
CF_TRY_XOPEN_SOURCE
fi
fi
+fi # cf_cv_posix_visible
])