myth-dbus/m4/as-expand.m4
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changeset 865 3eeb6b565018
     1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/myth-dbus/m4/as-expand.m4	Wed Oct 24 20:01:02 2007 +0100
     1.3 @@ -0,0 +1,40 @@
     1.4 +dnl AS_AC_EXPAND(VAR, CONFIGURE_VAR)
     1.5 +dnl
     1.6 +dnl example
     1.7 +dnl AS_AC_EXPAND(SYSCONFDIR, $sysconfdir)
     1.8 +dnl will set SYSCONFDIR to /usr/local/etc if prefix=/usr/local
     1.9 +
    1.10 +AC_DEFUN([AS_AC_EXPAND],
    1.11 +[
    1.12 +  EXP_VAR=[$1]
    1.13 +  FROM_VAR=[$2]
    1.14 +
    1.15 +  dnl first expand prefix and exec_prefix if necessary
    1.16 +  prefix_save=$prefix
    1.17 +  exec_prefix_save=$exec_prefix
    1.18 +
    1.19 +  dnl if no prefix given, then use /usr/local, the default prefix
    1.20 +  if test "x$prefix" = "xNONE"; then
    1.21 +    prefix=$ac_default_prefix
    1.22 +  fi
    1.23 +  dnl if no exec_prefix given, then use prefix
    1.24 +  if test "x$exec_prefix" = "xNONE"; then
    1.25 +    exec_prefix=$prefix
    1.26 +  fi
    1.27 +
    1.28 +  full_var="$FROM_VAR"
    1.29 +  dnl loop until it doesn't change anymore
    1.30 +  while true; do
    1.31 +    new_full_var="`eval echo $full_var`"
    1.32 +    if test "x$new_full_var"="x$full_var"; then break; fi
    1.33 +    full_var=$new_full_var
    1.34 +  done
    1.35 +
    1.36 +  dnl clean up
    1.37 +  full_var=$new_full_var
    1.38 +  AC_SUBST([$1], "$full_var")
    1.39 +
    1.40 +  dnl restore prefix and exec_prefix
    1.41 +  prefix=$prefix_save
    1.42 +  exec_prefix=$exec_prefix_save
    1.43 +])