#!/usr/bin/perl -w
use strict;
use Cwd;
# depends on: dpkg, tsort, perl
my $lib_dir = "/usr/lib/emacsen-common";
my $var_dir = "/var/lib/emacsen-common";
$::installed_package_state_dir = "${var_dir}/state/package/installed";
$::installed_flavor_state_dir = "${var_dir}/state/flavor/installed";
sub ex
{
my(@cmd) = @_;
if(system(@cmd) != 0)
{
die join(" ", @cmd) . " failed";
}
}
sub glob_in_dir
{
my ($dir, $pattern) = @_;
my $oldir = getcwd;
chdir($dir) or die "chdir $dir: $!";
my @files = glob("*[!~]");
chdir($oldir);
return \@files;
}
sub validate_add_on_pkg
{
my ($pkg, $script, $old_invocation_style) = @_;
if($old_invocation_style)
{
if(-e "$lib_dir/packages/compat/$pkg")
{
print STDERR "ERROR: $pkg is broken - called $script as an old-style add-on, but has compat file.\n";
#exit(1);
}
}
else # New invocation style.
{
unless(-e "$lib_dir/packages/compat/$pkg")
{
print STDERR "ERROR: $pkg is broken - called $script as a new-style add-on, but has no compat file.\n";
#exit(1);
}
}
}
sub get_installed_add_on_packages
{
# Return all of the old format packages, plus all of the new-format
# packages that are ready (i.e. have a state/installed file). In
# this case ready means ready for compilation.
my $all_pkgs = glob_in_dir("$lib_dir/packages/install", '*[!~]');
my $new_format_pkgs = glob_in_dir("$lib_dir/packages/compat", '*[!~]');
my %ready_pkgs = map { $_ => 1 } @$all_pkgs;
for my $p (@$new_format_pkgs)
{
delete $ready_pkgs{$p} unless (-e "$::installed_package_state_dir/$p");
}
my @result = keys %ready_pkgs;
return \@result;
}
sub get_installed_flavors
{
my $flavors = glob_in_dir($::installed_flavor_state_dir, '*[!~]');
return @$flavors;
}
sub get_package_status
{
my($pkg) = @_;
my $status = `dpkg --status $pkg`;
die 'emacsen-common: dpkg invocation failed' if($? != 0);
$status =~ s/\n\s+//gmo; # handle any continuation lines...
return $status;
}
sub filter_depends
{
my($depends_string, $installed_add_ons) = @_;
# Filter out all the "noise" (version number dependencies, etc)
# and handle or deps too, i.e. "Depends: foo, bar | baz"
my @relevant_depends = split(/[,|]/, $depends_string);
@relevant_depends = map { /\s*(\S+)/o; $1; } @relevant_depends;
# Filter out all non-add-on packages.
@relevant_depends = grep {
my $candidate = $_;
grep { $_ eq $candidate } @$installed_add_ons;
} @relevant_depends;
return @relevant_depends;
}
sub generate_relevant_tsort_dependencies_internals
{
my($pkglist, $installed_add_ons, $progress_hash) = @_;
# print "GRD: " . join(" ", @$pkglist) . "\n";
my $pkg = shift @$pkglist;
if(!$pkg || $$progress_hash{$pkg}) {
return ();
} else {
my $status = get_package_status($pkg);
$status =~ /^Depends:\s+(.*)/mo;
my $depends = $1; $depends = "" if ! $depends;
my @relevant_depends = filter_depends($depends, $installed_add_ons);
my $newpkglist = [@$pkglist, @relevant_depends];
$$progress_hash{$pkg} = 1;
# pkg is in twice so we don't have to worry about package with no
# relevant dependencies. tsort can't handle that.
my @tsort_strings = "$pkg $pkg\n";
map { push @tsort_strings, "$_ $pkg\n"; } @relevant_depends;
return (@tsort_strings,
generate_relevant_tsort_dependencies_internals($newpkglist,
$installed_add_ons,
$progress_hash));
}
}
sub generate_relevant_tsort_dependencies
{
my($pkglist, $installed_add_ons, $progress_hash) = @_;
# Make a copy because we're going to mangle it.
my @listcopy = @$pkglist;
shift @_;
return(generate_relevant_tsort_dependencies_internals(\@listcopy, @_));
}
sub reorder_add_on_packages
{
my($pkglist, $installed_add_ons) = @_;
my @depends = generate_relevant_tsort_dependencies($pkglist,
$installed_add_ons,
{});
my $pid = open(TSORT, "-|");
die "Couldn't fork for tsort: $!" unless defined($pid);
# What a strange idiom...
if($pid == 0) {
my $sub_pid = open(IN, "|-");
die "Couldn't sub-fork for tsort: $!" unless defined($sub_pid);
if($sub_pid == 0) {
exec 'tsort' or die "Couldn't run tsort: $!";
}
print IN @depends;
exit 0;
}
my @ordered_pkgs = <TSORT>;
chomp @ordered_pkgs;
return @ordered_pkgs
}
sub generate_add_on_install_list
{
my($packages_to_sort) = @_;
my @sorted_pkgs = reorder_add_on_packages($packages_to_sort,
get_installed_add_on_packages());
return(@sorted_pkgs);
}
# Test code
# my @input_packages = <STDIN>;
# my @result = generate_add_on_install_list(@input_packages);
# print " " . join("\n ", @result);
# To make require happy...
1;
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