#!/usr/bin/perl
use warnings;
use strict;

## Scott Wiersdorf
## Created: Thu May 17 11:23:02 MDT 2007
## $Id: mailsender,v 1.1 2007/05/17 17:39:59 scott Exp $

## mailsender: find the senders given a recipient

## usage: mailsender 'joe@recipient.tld' /var/log/maillog.0.gz ...

our $VERSION = '0.90';

my $rcpt = shift @ARGV;
my @files = @ARGV;

open(PIPE, '-|', 'zgrep', $rcpt, @files)
  or do {
      die "Could not open pipe: $!\n";
  };

my %ids = ();

while( <PIPE> ) {
    next unless m{\bsm\-mta\b.+?: (\S+?):(?: Milter:)? to=<$rcpt>}o;
    $ids{$1} = 1;
}

close PIPE;

## open pipe again
open(PIPE, '-|', 'zcat', '-f', @files)
  or do {
      die "Could not open pipe: $!\n";
  };

my %sender = ();

while( <PIPE> ) {
    next unless m{: ([^:]+): from=<?(.+?)>?,}o;
    next unless exists $ids{$1};
    $sender{$2}++;
}

close PIPE;

for my $sender ( sort { $sender{$b} <=> $sender{$a} } keys %sender ) {
    print "$sender ($sender{$sender})\n";
}

exit;