gnulib/m4/physmem.m4

# physmem.m4 serial 12
dnl Copyright (C) 2002-2003, 2005-2006, 2008-2020 Free Software Foundation,
dnl Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.

# Check for the external symbol, _system_configuration,
# a struct with member 'physmem'.
AC_DEFUN([gl_SYS__SYSTEM_CONFIGURATION],
  [AC_CACHE_CHECK([for external symbol _system_configuration],
                  [gl_cv_var__system_configuration],
    [AC_LINK_IFELSE([AC_LANG_PROGRAM(
                      [[#include <sys/systemcfg.h>
                      ]],
                      [[double x = _system_configuration.physmem;
                        if (x > 0.0) return 0;]])],
      [gl_cv_var__system_configuration=yes],
      [gl_cv_var__system_configuration=no])])

    if test $gl_cv_var__system_configuration = yes; then
      AC_DEFINE([HAVE__SYSTEM_CONFIGURATION], [1],
                [Define to 1 if you have the external variable,
                _system_configuration with a member named physmem.])
    fi
  ]
)

AC_DEFUN([gl_PHYSMEM],
[
  # Prerequisites of lib/physmem.c.
  AC_CHECK_HEADERS([sys/pstat.h sys/sysmp.h sys/sysinfo.h \
    machine/hal_sysinfo.h sys/table.h sys/param.h sys/systemcfg.h],,,
    [AC_INCLUDES_DEFAULT])
  dnl <sys/sysctl.h> requires <sys/param.h> on OpenBSD 4.0.
  AC_CHECK_HEADERS([sys/sysctl.h],,,
    [AC_INCLUDES_DEFAULT
     #if HAVE_SYS_PARAM_H
     # include <sys/param.h>
     #endif
    ])

  AC_CHECK_FUNCS([pstat_getstatic pstat_getdynamic sysmp getsysinfo sysctl table sysinfo])
  AC_CHECK_MEMBERS([struct sysinfo.mem_unit],,, [[#include <sys/sysinfo.h>]])
  AC_REQUIRE([gl_SYS__SYSTEM_CONFIGURATION])
])