gnulib/import/m4/getpagesize.m4

# getpagesize.m4 serial 10
dnl Copyright (C) 2002, 2004-2005, 2007, 2009-2021 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.

AC_DEFUN([gl_FUNC_GETPAGESIZE],
[
  AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
  AC_REQUIRE([AC_CANONICAL_HOST])
  gl_CHECK_FUNC_GETPAGESIZE
  if test $gl_cv_func_getpagesize = no; then
    HAVE_GETPAGESIZE=0
    AC_CHECK_HEADERS([OS.h])
    if test $ac_cv_header_OS_h = yes; then
      HAVE_OS_H=1
    fi
    AC_CHECK_HEADERS([sys/param.h])
    if test $ac_cv_header_sys_param_h = yes; then
      HAVE_SYS_PARAM_H=1
    fi
  fi
  case "$host_os" in
    mingw*)
      REPLACE_GETPAGESIZE=1
      ;;
  esac
  dnl Also check whether it's declared.
  dnl mingw has getpagesize() in libgcc.a but doesn't declare it.
  AC_CHECK_DECL([getpagesize], , [HAVE_DECL_GETPAGESIZE=0])
])

dnl Tests whether the function getpagesize() exists.
dnl Sets gl_cv_func_getpagesize.
AC_DEFUN([gl_CHECK_FUNC_GETPAGESIZE],
[
  dnl We can't use AC_CHECK_FUNC here, because getpagesize() is defined as a
  dnl static inline function when compiling for Android 4.4 or older.
  AC_CACHE_CHECK([for getpagesize], [gl_cv_func_getpagesize],
    [AC_LINK_IFELSE(
       [AC_LANG_PROGRAM(
          [[#include <unistd.h>]],
          [[return getpagesize();]])
       ],
       [gl_cv_func_getpagesize=yes],
       [gl_cv_func_getpagesize=no])
    ])
])