freebsd-dev/acinclude.m4

dnl from autoconf 2.13 acspecific.m4, with changes to check for daylight

AC_DEFUN([AC_STRUCT_TIMEZONE_DAYLIGHT],
[AC_REQUIRE([AC_STRUCT_TM])dnl
AC_CACHE_CHECK([for tm_zone in struct tm], ac_cv_struct_tm_zone,
[AC_TRY_COMPILE([#include <sys/types.h>
#include <$ac_cv_struct_tm>], [struct tm tm; tm.tm_zone;],
  ac_cv_struct_tm_zone=yes, ac_cv_struct_tm_zone=no)])
if test "$ac_cv_struct_tm_zone" = yes; then
  AC_DEFINE(HAVE_TM_ZONE,1,[HAVE_TM_ZONE])
fi
AC_CACHE_CHECK(for tzname, ac_cv_var_tzname,
[AC_TRY_LINK(
changequote(<<, >>)dnl
<<#include <time.h>
#ifndef tzname /* For SGI.  */
extern char *tzname[]; /* RS6000 and others reject char **tzname.  */
#endif>>,
changequote([, ])dnl
[atoi(*tzname);], ac_cv_var_tzname=yes, ac_cv_var_tzname=no)])
  if test $ac_cv_var_tzname = yes; then
    AC_DEFINE(HAVE_TZNAME,1,[HAVE_TZNAME])
  fi

AC_CACHE_CHECK([for tm_isdst in struct tm], ac_cv_struct_tm_isdst,
[AC_TRY_COMPILE([#include <sys/types.h>
#include <$ac_cv_struct_tm>], [struct tm tm; tm.tm_isdst;],
  ac_cv_struct_tm_isdst=yes, ac_cv_struct_tm_isdst=no)])
if test "$ac_cv_struct_tm_isdst" = yes; then
  AC_DEFINE(HAVE_TM_ISDST,1,[HAVE_TM_ISDST])
fi
AC_CACHE_CHECK(for daylight, ac_cv_var_daylight,
[AC_TRY_LINK(
changequote(<<, >>)dnl
<<#include <time.h>
#ifndef daylight /* In case IRIX #defines this, too  */
extern int daylight;
#endif>>,
changequote([, ])dnl
[atoi(daylight);], ac_cv_var_daylight=yes, ac_cv_var_daylight=no)])
  if test $ac_cv_var_daylight = yes; then
    AC_DEFINE(HAVE_DAYLIGHT,1,[HAVE_DAYLIGHT])
  fi
])