#!/usr/bin/perl -w
#
# $(srcdir)/build-aux/subdirmk-setup SUBDIR...
#
# generates
#   Subdir.mk.tmp
#   Makefile.tmp

use strict;

our @allsubdirs = @ARGV;

sub write_makefile ($$) {
    my ($subdir,$depth)
    start_output_file("Makefile");
    my $cd = $depth ? join('/', ('..',) x $depth) : '.';
    print O <<END;
# autogenerated - do not edit
%:
	\$(MAKE) -C $cd $subdir/\$@
END
}

sub require_subdir ($) {
    # => list of descendant subdirs
    my ($here) = (@_);
    my $prefix = $here eq '.' ? qr{} : qr{$prefix/};
    my @children = grep { m{^$prefix[^/]+$} } @allsubdirs;
    my @descendants;
    foreach my $child (@children) {
	push @descendants, require_subdir(

	$subdir, grep { $_ =~ m{^$subdir/} } 
    printf O "include $_/Subdir.mk"
	


sub process_subdir ($$) {
    my ($subdir) = @_;
    my $depth = $subdir eq '.' ? 0 : scalar split m{/+}, $subdir;
    write_makefile($subdir,$depth);
    require_subdir($subdir);
}

foreach (@allsubdirs) { process_subdir($_); }