dnl as-ac-expand.m4 0.1.0
dnl autostars m4 macro for expanding directories using configure's prefix
dnl thomas@apestaart.org 

dnl AS_AC_EXPAND(VAR, CONFIGURE_VAR)
dnl
dnl example
dnl AS_AC_EXPAND(SYSCONFDIR, $sysconfdir)
dnl will set SYSCONFDIR to /usr/local/etc if prefix=/usr/local

AC_DEFUN([AS_AC_EXPAND],
[
  EXP_VAR=[$1]
  FROM_VAR=[$2]

  dnl first expand prefix and exec_prefix if necessary
  prefix_save=$prefix
  exec_prefix_save=$exec_prefix

  dnl if no prefix given, then use /usr/local, the default prefix
  if test "x$prefix" = "xNONE"; then
    prefix=$ac_default_prefix
  fi
  dnl if no exec_prefix given, then use prefix
  if test "x$exec_prefix" = "xNONE"; then
    exec_prefix=$prefix
  fi

  full_var="$FROM_VAR"
  dnl loop until it doesn't change anymore
  while true; do
    new_full_var="`eval echo $full_var`"
    if test "x$new_full_var"="x$full_var"; then break; fi
    full_var=$new_full_var
  done

  dnl clean up
  full_var=$new_full_var
  AC_SUBST([$1], "$full_var")

  dnl restore prefix and exec_prefix
  prefix=$prefix_save
  exec_prefix=$exec_prefix_save
])

dnl GTK_DOC_CHECK borrowed from cairo, thanks!

dnl Usage:
dnl   GTK_DOC_CHECK([minimum-gtk-doc-version])
AC_DEFUN([GTK_DOC_CHECK],
[
  AC_BEFORE([AC_PROG_LIBTOOL],[$0])dnl setup libtool first
  AC_BEFORE([AM_PROG_LIBTOOL],[$0])dnl setup libtool first
  dnl for overriding the documentation installation directory
  AC_ARG_WITH(html-dir,
    AC_HELP_STRING([--with-html-dir=PATH], [path to installed docs]),,
    [with_html_dir='${datadir}/gtk-doc/html'])
  HTML_DIR="$with_html_dir"
  AC_SUBST(HTML_DIR)

  dnl enable/disable documentation building
  AC_ARG_ENABLE(gtk-doc,
    AC_HELP_STRING([--enable-gtk-doc],
                   [use gtk-doc to build documentation [default=yes]]),,
    enable_gtk_doc=yes)

  have_gtk_doc=no
  if test x$enable_gtk_doc = xyes; then
    if test -z "$PKG_CONFIG"; then
      AC_PATH_PROG(PKG_CONFIG, pkg-config, no)
    fi
    if test "$PKG_CONFIG" != "no" && $PKG_CONFIG --exists gtk-doc; then
      have_gtk_doc=yes
    fi

  dnl do we want to do a version check?
ifelse([$1],[],,
    [gtk_doc_min_version=$1
    if test "$have_gtk_doc" = yes; then
      AC_MSG_CHECKING([gtk-doc version >= $gtk_doc_min_version])
      if $PKG_CONFIG --atleast-version $gtk_doc_min_version gtk-doc; then
        AC_MSG_RESULT(yes)
      else
        AC_MSG_RESULT(no)
        have_gtk_doc=no
      fi
    fi
])
    if test "$have_gtk_doc" != yes; then
      enable_gtk_doc=no
    fi
  fi

  AM_CONDITIONAL(ENABLE_GTK_DOC, test x$enable_gtk_doc = xyes)
  AM_CONDITIONAL(GTK_DOC_USE_LIBTOOL, test -n "$LIBTOOL")
])