show_repos_of_pkgs_debian.pl

use strict;
use warnings;

# Find all installed packages
my $out = `dpkg-query -l`;

# Lines like:
# ii  zlib1g-dev:i386   1:1.2.8.dfsg- i386          compression library - development

my @lines = split /\n/, $out;

foreach my $line (@lines) {
        my @pieces = split /\s+/, $line;

        my $status = $pieces[0];
        next unless $status eq 'ii';
        my $name = $pieces[1];

        # Look up its repo
        # Lines like:
        # irssi |   0.8.20-2 | http://ftp.ca.debian.org/debian stretch/main i386 Packages

        # May have multiple lines if have source defined.
        my $madison = `apt-cache madison $name`;
        my @madison_lines = split /\n/, $madison;

        if (@madison_lines == 0) {
                print "$name MISSING INFO\n";
                next;
        }

        my @pieces2 = split /\|/, $madison_lines[0];
        if (@pieces2 < 3) {
                print "$name MISSING INFO\n";
                next;
        }
        my $repo = $pieces2[2];
        $repo =~ s/^\s+|\s+$//g;

        print "$name: $repo\n";
}