openbsd-ports/infrastructure/build/extract-dependencies

65 lines
1.6 KiB
Perl

#! /usr/bin/perl
# $OpenBSD: extract-dependencies,v 1.2 2005/10/22 18:05:34 espie Exp $
#
# Copyright (c) 2005 Marc Espie <espie@openbsd.org>
#
# Permission to use, copy, modify, and distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
# Usage: extract-dependencies < 'tsort-pairs' seed
# extracts all the dependencies for seed from a list that contains more
# than that.
use strict;
use warnings;
use Getopt::Std;
my %opts;
getopts('r', \%opts);
# build dependency graph
my $dep = {};
while(<STDIN>) {
chomp;
my ($a, $b) = split(/\s+/, $_);
if ($opts{r}) {
($a, $b) = ($b, $a);
}
$dep->{$a} = {} unless defined $dep->{$a};
$dep->{$a}->{$b} = 1;
}
# get the starting point
my $pkgpath = shift;
my @todo = ();
my $done = {};
# walk the graph repeatedly starting from it
push(@todo, $pkgpath);
while (my $x = shift @todo) {
next if $done->{$x};
$done->{$x} = 1;
next unless defined $dep->{$x};
push(@todo, keys %{$dep->{$x}});
}
# display all nodes, except for the seed
for my $d (keys %$done) {
next if $d eq $pkgpath;
print "$d\n";
}