dnl
dnl Some autoconf macros useful for device driver configuration
dnl

AC_SUBST(device_drivers)

dnl AC_DRIVER_ALIAS(alias, canonical) makes --enable-alias have the
dnl same effect as --enable-canonical.

AC_DEFUN(AC_DRIVER_ALIAS, [
[#] Checking for alias [$1]
AC_ARG_ENABLE([$1],,
enable_[$2]="$enable_[$1]"
)])

dnl AC_DRIVER_CLASS(name,option,files) defines a class of drivers.  If
dnl any driver declared by AC_DRIVER to be in that class is selected
dnl by the user, then set the specified option with AC_DEFINE and add
dnl the specified files to the output variable `device_drivers'.  This
dnl macro must precede the use of any corresponding AC_DRIVER macros.

AC_DEFUN(AC_DRIVER_CLASS, [
driver_class_[$1]_option=[$2]
driver_class_[$1]_files="[$3]"
])

dnl AC_DRIVER(name,option,files [,class]) detects option --enable-name.  If
dnl it's set, then `option' is defined with AC_DEFINE, and files is
dnl added to the output variable `device_drivers'.  The driver is of class 
dnl `class'; see the comments on AC_DRIVER_CLASS for more information.

AC_DEFUN(AC_DRIVER, [
[#] Checking for device driver option [$1]
AC_ARG_ENABLE([$1],,
AC_DEFINE([$2])
device_drivers="$device_drivers [$3]"
if test "driver_class_[$4]_selected+set" != set; then
  driver_class_[$4]_selected=yes
  AC_DEFINE_UNQUOTED($driver_class_[$4]_option)
  device_drivers="$device_drivers $driver_class_[$4]_files"
fi
)])