ax_arg.m4

dnl __BEGIN_LICENSE__
dnl Copyright (C) 2006-2010 United States Government as represented by
dnl the Administrator of the National Aeronautics and Space Administration.
dnl All Rights Reserved.
dnl __END_LICENSE__


m4_ifdef([_AX_FIXUPS], [], [m4_include([m4/fixups.m4])])

dnl AX_ARG_(ENABLE|WITH)(<arg>, <default>, <tags>, <description>)
dnl possible tags are:
dnl    always -> set autoconf macro       to value
dnl        mk -> set Makefile variable    to value
dnl   cpp-int -> set config.h value       to value
dnl  cpp-bool -> set config.h value       to int(bool(value == yes))
dnl    am-yes -> set automake conditional to bool(value == yes)
dnl    am-set -> set automake conditional to bool(-n value)
dnl
dnl variable in question is ether ENABLE_ARG or ARG (the "with" is dropped)

dnl AX_ARG(<type>, <arg>, <default>, <tags>, <description>)
AC_DEFUN([AX_ARG],
[
  m4_pushdef([lower], my_tolower([$2]))dnl lower-case arg name
  m4_pushdef([type],  my_toupper([$1]))dnl WITH or ENABLE
  AS_VAR_PUSHDEF([value], m4_if(type, [WITH], [], type[_])[]m4_toupper([[$2]]))dnl


  m4_divert_once([INIT_PREPARE], [dnl
  dnl switch between AC_ARG_(WITH|ENABLE), since I don't think you can indirect
  m4_if(type, [WITH],
    dnl WITH case.
    [AC_ARG_WITH(lower,
    AS_HELP_STRING([--with]-lower, [$5][ ]m4_ifval([$3],[@<:@$3@:>@])), dnl append default value to the desc
    [ value=[$withval] ],                                dnl if passed in, set value
    [ AS_VAR_SET_IF([value], [], [value="[$3]"]) ])],    dnl else set to default if not already set

    dnl ENABLE case. same as above except if default is yes, change enable -> disable
    [AC_ARG_ENABLE(lower,
    AS_HELP_STRING([--][]m4_if(yes, [$3], disable, enable)-lower, [$5][ ]m4_ifval([$3],[@<:@$3@:>@])),
    [ value=[$enableval] ],
    [ AS_VAR_SET_IF([value], [], [value="[$3]"]) ])])])

  dnl if the tag is none, generate no configure code here
  m4_bmatch([$4], [none], [], [dnl

    dnl check for am-yes tag. var name is shell-escaped
    m4_bmatch([$4], [am-yes], [dnl
      AM_CONDITIONAL(AS_TR_SH(value), [test x"$value" = x"yes"])dnl
    ])dnl

    dnl check for am-set tag. var name is shell-escaped
    m4_bmatch([$4], [am-set], [dnl
      AM_CONDITIONAL(AS_TR_SH(value), [test ! -z "$value"])dnl
    ])dnl

    dnl check for cpp-bool tag.
    m4_bmatch([$4], [cpp-bool], [dnl
      AS_VAR_PUSHDEF([int], my_tolower(value))
      AS_IF([test x"$value" = x"yes"], int=1, int=0)
      AC_DEFINE_UNQUOTED(AS_TR_CPP(value), [$int], [$5])
      AS_VAR_POPDEF([int])dnl
    ])dnl

    dnl check for cpp-int tag.
    m4_bmatch([$4], [cpp-int], [dnl
      AS_VAR_PUSHDEF([int], my_tolower(value))dnl
      int=$value dnl
      AC_DEFINE_UNQUOTED(AS_TR_CPP(value), [$int], [$5])dnl
      AS_VAR_POPDEF([int])dnl
    ])dnl

    m4_bmatch([$4], [mk], [dnl
      AC_SUBST(AS_TR_SH(value))dnl
    ])dnl

  ])dnl

  dnl clean up after myself
  AS_VAR_POPDEF([value])dnl
  m4_popdef([type])dnl
  m4_popdef([lower])dnl
])

AC_DEFUN([AX_ARG_ENABLE], [AX_ARG([enable], [$1], [$2], [$3], [$4])])
AC_DEFUN([AX_ARG_WITH],   [AX_ARG([with],   [$1], [$2], [$3], [$4])])