source: soft/build_system/build_system/mkcd/tags/V4_0_6_1mdk/gendeps @ 1

#!/usr/bin/perl

use strict;

my $a = shift @ARGV or usage();
getdeps($a, \@ARGV);

exit;

sub usage{
        print "
        usage:
                $0 basedir packages_list\n
";
        exit
}

sub getdeps{
        my ($topdir,$listrpms) = @_;
        my ($pkg,$name,$deps) = gendeps($topdir);
        $listrpms = deps($pkg,$name,$deps,[0,$listrpms],1);
        foreach (@{$listrpms->[1]}) { ref $_ and print "@$_\n" or print "$_\n"}
}

sub gendeps{
        my ($topdir) = @_;
        my %log;
        -f "$topdir/depslist.ordered" or die "cannot find $topdir/depslist.ordered\n";
        open DEP, "$topdir/depslist.ordered";

        print LOG "getting dependencies\n";
        my @deps;
        my @rdeps;
        my %pkg;
        my $i = 0;
        my @name;
        foreach (<DEP>){
                chomp;
                my ($name, $size, @de) = split " ", $_; 
                ($name, my $version, my $release) = $name =~ /(.*)-([^-]*)-([^-]*)/;
                if ($name){
                        foreach my $d (@de) {
                                if ($d =~ s/^NOTFOUND_//) { 
                                        push @{$log{"$name"}}, $d;
                                }else{
                                        if ($d =~ /\|/){ 
                                                my @t = split '\|',$d ; my @u; 
                                                foreach my $t (@t) { if ($t =~ s/NOTFOUND_//) {push @{$log{"$name"}}, $d} else { push @u, $t; push @{$rdeps[$t]}, $i} }
                                                push @{$deps[$i]}, \@u
                                        }else { push @{$deps[$i]}, $d; push @{$rdeps[$d]}, $i}
                                }
                        }
                        $name[$i] = $name;
                        $pkg{$name} = $i;
                        $i++;
                }
        }
        print LOG "FAILING DEPS\n";
        foreach my $k (keys %log){
                print LOG "$k @{$log{$k}}\n";
        }
        return (\%pkg,\@name,\@deps,\@rdeps)
}

sub deps{
        my ($pkg,$name,$deps,$listrpms,$alt) = @_;
                my @listlin;
                my %listalt;
                for(my $i=1; $i < @$listrpms; $i++){
                        foreach my $p (@{$listrpms->[$i]}){
                                $listlin[$pkg->{$p}] = $i; 
                        }
                }       
                $listlin[$pkg->{"basesystem"}] = 1;
                my $n=1;
                my $lo=0;
                while ($n){
                        $lo++;
                        $n=0;
                        for(my $i = 0; $i < @listlin; $i++){
                                if ($listlin[$i]){
                                        foreach (@{$deps->[$i]}){
                                                if (!ref) { if ((! $listlin[$_]) or ($listlin[$i] < $listlin[$_])) { $listlin[$_] = $listlin[$i] ; $n = 1} }
                                                elsif ($alt){
                                                        my $ok;
                                                        foreach (@{$_}){
                                                                if ($listlin[$_] and ($listlin[$i] > $listlin[$_])) { $ok=1; last} 
                                                        }
                                                        !$ok and do {
                                                                        my $l = [map $name->[$_],@{$_}];
                                                                        if (!$listalt{"@$l"} or $listalt{"@$l"}->[0] > $listlin[$i]){
                                                                                $listalt{"@$l"} = [$listlin[$i],$l]
                                                                        }
                                                        }
                                                }
                                        }
                                }
                        }       
                }
                for(my $i = 0; $i < @listlin; $i++){
                                $listlin[$i] and push @{$listrpms->[$listlin[$i]]}, $name->[$i]
                }
                if ($alt) {
                        foreach (keys %listalt){
                                push @{$listrpms->[$listalt{$_}->[0]]}, $listalt{$_}->[1];
                        }
                }
        return $listrpms;
}