#!/usr/bin/perl

require 5.002;
use strict 'subs';
use English;

sub check_uid($$$$$$) {
    my ($name, $uid, $gid, $gecos, $home, $shell) = @_;
    my $ok = 1;

    print "Checking user $name (uid $uid, gid $gid, homedir $home)... ";
    @name_entry = getpwnam("$name");
    if ( @name_entry == () ) {
	my @uid_entry = getpwuid($uid);
	if ( @uid_entry == () ) {
	    system("adduser --system --quiet --home $home --gid $gid --uid $uid --gecos \'$gecos\' $name >/dev/null 2>&1");
	    if ( $? != 0 ) {
		print "\n Error while adding user $name!\n";
		$ok = 0;
	    }
	    else {
		print "added.\n";
	    }
	    system("chsh -s $shell $name");
	}
	else {
	    print "error!\n Uid $uid is being used by user $uid_entry[0]\n";
	    $ok = 0;
	}
    }
    else {
	if ( $name_entry[3] != $gid ) {
	    print "error!\n" if $ok;
	    print " User $name has primary group $name_entry[3] instead of $gid\n";
	    $ok = 0;
	}
	if ( $name_entry[2] != $uid ) {
	    print "error!\n" if $ok;
	    print " User $name has uid $name_entry[2] instead of $uid\n";
	    $ok = 0;
	}
	if ( $name_entry[7] ne $home ) {
	    print "error!\n" if $ok;
	    print " User $name has home directory $name_entry[7] instead of $home\n";
	    $ok = 0;
	}
	if ( $ok ) {
	    print "ok.\n";
	}
    }
    return $ok;
}

sub check_gid($$@) {
    my ($name, $gid, @members) = @_;
    my $ok = 1;

    print "Checking group $name (gid $gid)... ";
    @name_entry = getgrnam($name);
    if ( @name_entry == () ) {
	my @gid_entry = getgrgid($gid);
	if ( @gid_entry == () ) {
	    system("addgroup --quiet --gid $gid $name");
	    if ( $? != 0 ) {
		print "\n Error while adding group $name\n";
		$ok = 0;
	    }
	    else {
		print "added.\n";
	    }
	}
	else {
	    print "error!\n Gid $gid is being used by group $gid_entry[0]\n";
	    $ok = 0;
	}
    }
    else {
	if ( $name_entry[2] != $gid ) {
	    print "error!\n Group $name has gid $name_entry[2] instead of $gid\n";
	    $ok = 0;
	}
	if ( $ok ) {
	    print "ok.\n";
	}
    }
    return $ok;
}

sub is_qmail_installed {
    my $qmail_installed = 0;

    print "Checking if qmail is already installed on this computer... ";

    $qmail_home = '';
    if ( -d '/var/qmail' ) {
	print "\n Found /var/qmail directory";
	$qmail_home = '/var/qmail';
	$qmail_installed = 1;
    }
    else {
	$qmail_home = `qmail-home`;
	if ( $qmail_home ne '') {
	    print "\n Found qmail home directory at $qmail_home (using qmail-home program)";
	    $qmail_installed = 1;
	}
    }

    if ( -d '/var/spool/qmail' ) {
	print "\n Found qmail spool directory at /var/spool/qmail";
	$qmail_installed = 1;
    }
    if ( -d '/etc/qmail' ) {
	print "\n Found qmail control directory at /etc/qmail";
	$qmail_installed = 1;
    }
    
    if ( (-r '/etc/inetd.conf') and `fgrep -q qmail-smtpd /etc/inetd.conf` ) {
	print "\n Found reference to qmail-smtpd in /etc/inetd.conf";
	$qmail_installed = 1;
    }
    if ( (-r '/etc/xinetd.conf') and `fgrep -q qmail-smtpd /etc/xinetd.conf` ) {
	print "\n Found reference to qmail-smtpd in /etc/xinetd.conf";
	$qmail_installed = 1;
    }

    if ( -x '/etc/init.d/qmail' ) {
	print "\n Found /etc/init.d/qmail script";
	$qmail_installed = 1;
    }
    elsif ( `fgrep -q qmail-start /etc/init.d/*` ) {
	print "\n Found reference to qmail-start in /etc/init.d directory";
	$qmail_installed = 1;
    }
    if ( -x '/etc/rc.local' and `fgrep -q qmail-start /etc/rc.local` ) {
	print "\n Found reference to qmail-start in /etc/rc.local";
	$qmail_installed = 1;
    }

    if ( `killall -0 qmail-send >/dev/null 2>&1` ) {
	print "\n Found qmail-send process running";
	$qmail_installed = 1;
    }

    print 'no.' unless $qmail_installed;
    print "\n";
    return $qmail_installed;
}
	

$| = 1;

$action = shift;

if ( $action eq 'install' ) {
    $old_version = shift;
    if ( ! defined $old_version || $old_version eq '' ) {
	print "First installation of the Debian qmail package...\n";
	# Check if a non-Debian qmail is installed...
	if ( is_qmail_installed() ) {
	    print "Please remove your copy of qmail before installing the qmail Debian package.\n\n";
	    exit 1;
	}
	# Check for qmail uids and gids
	my $errors;
	$errors++ unless check_gid('qmail', 64010, ());
	#$errors++ unless check_gid('nogroup', 65534, ());

	$errors++ unless check_uid('alias', 64010, 65534, 'qmail alias', '/var/qmail/alias', '/bin/sh');
	$errors++ unless check_uid('qmaild', 64011, 65534, 'qmail daemon', '/var/qmail', '/bin/sh');
	$errors++ unless check_uid('qmails', 64012, 64010, 'qmail send', '/var/qmail', '/bin/sh');
	$errors++ unless check_uid('qmailr', 64013, 64010, 'qmail remote', '/var/qmail', '/bin/sh');
	$errors++ unless check_uid('qmailq', 64015, 64010, 'qmail queue', '/var/qmail', '/bin/sh');
	$errors++ unless check_uid('qmaill', 64016, 65534, 'qmail log', '/var/qmail', '/bin/sh');
	$errors++ unless check_uid('qmailp', 64017, 65534, 'qmail pw', '/var/qmail', '/bin/sh');
	#$errors++ unless check_uid('nobody', 65534, 65534, 'nobody', '/tmp', '/bin/sh');

	if ( $errors ) {
	    print "\n$errors entries have errors. Please correct these errors and reinstall qmail.\n";
	    exit 2;
	}
    }

    # Make sure there are no smtp entries in /etc/inetd.conf
    # Kludge around smail buggy /etc/inetd.conf handling. (Grr.)
    my $fixed_smail = 0;
    my $found_commented = 0;
    my $found_uncommented = 0;
    my $new_inetd = "/etc/inetd.conf.qmail-preinst.$$";
    open I, '</etc/inetd.conf' or die "Could not open /etc/inetd.conf\n";
    open N, ">$new_inetd" or die "Could not create $new_inetd\n";
    while (<I>) {
	if ( m|^\# *smtp\s+.*/usr/sbin/in.smtpd.*\(will be restored by smail postinst\)\s*$| ) {
                $fixed_smail = 1;
		next;
            } elsif ( m/^\# *smtp\s+/ ) {
                $found_commented= 1;
            } elsif ( m/^smtp\s+/ ) {
                $found_uncommented= 1;
            }
	print N or die "Cannot write to $new_inetd\n";
	}
    close N or die "Could not close $new_inetd\n";
    close I or die "Could not close /etc/inetd.conf\n";
    if ( $found_commented or $found_uncommented ) {
	print "Your /etc/inetd.conf already containts entries for the SMTP service.\n";
	print "Please remove all SMTP entries from /etc/inetd.conf (even those commented out)\n";
	print "and reinstall the qmail package.\n\n";
	exit 1; 
    }
    if ( $fixed_smail ) {
	print "Removing commented smtp entry left by buggy version of smail postinst... ";
	rename "$new_inetd", '/etc/inetd.conf' or die "failed!\n";
	print "done.\n";
    }
}

exit 0;