"Blank page" too often lately...

<?php
/***********************************************************************

  Copyright (C) 2002-2005  Rickard Andersson (rickard@punbb.org)

  This file is part of PunBB.

  PunBB is free software; you can redistribute it and/or modify it
  under the terms of the GNU General Public License as published
  by the Free Software Foundation; either version 2 of the License,
  or (at your option) any later version.

  PunBB is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  MA  02111-1307  USA

************************************************************************/


// Make sure no one attempts to run this script "directly"
if (!defined('PUN'))
    exit;


//
// Validate an e-mail address
//
function is_valid_email($email)
{
    if (strlen($email) > 50)
        return false;

    return preg_match('/^(([^<>()[\]\\.,;:\s@"\']+(\.[^<>()[\]\\.,;:\s@"\']+)*)|("[^"\']+"))@((\[\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\])|(([a-zA-Z\d\-]+\.)+[a-zA-Z]{2,}))$/', $email);
}


//
// Check if $email is banned
//
function is_banned_email($email)
{
    global $db, $pun_bans;

    foreach ($pun_bans as $cur_ban)
    {
        if ($cur_ban['email'] != '' &&
            ($email == $cur_ban['email'] ||
            (strpos($cur_ban['email'], '@') === false && stristr($email, '@'.$cur_ban['email']))))
            return true;
    }

    return false;
}


//
// Wrapper for PHP's mail()
//
function pun_mail($to, $subject, $message, $from = '')
{
    global $pun_config, $lang_common;

    // Default sender/return address
    if (!$from) {
        $from = '"'.str_replace('"', '', $pun_config['o_board_title'].' '.$lang_common['Mailer']).'" <'.$pun_config['o_webmaster_email'].'>';
// BEGIN FIX FOR UTF-8 ENCODING
        $from = iconv("UTF-8", "KOI8-R", $from);
// END FIX
    }
    // Do a little spring cleaning
    $to = trim(preg_replace('#[\n\r]+#s', '', $to));

// BEGIN FIX FOR UTF-8 ENCODING
// ORIGINAL:
//    $subject = trim(preg_replace('#[\n\r]+#s', '', $subject));
//    testing:
//    $subject = '=?UTF-8?B?'.base64_encode(trim(preg_replace('#[\n\r]+#s', '', $subject)))."?=\n";
    $subject = '=?KOI8-R?B?'.base64_encode(iconv("UTF-8", "KOI8-R", trim(preg_replace('#[\n\r]+#s', '', $subject))))."?=\n";
//    $subject = iconv("UTF-8", "windows-1251", trim(preg_replace('#[\n\r]+#s', '', $subject)));
// END FIX

    $from = trim(preg_replace('#[\n\r:]+#s', '', $from));

    $headers = 'From: '.$from."\r\n".'Date: '.date('r')."\r\n".'MIME-Version: 1.0'."\r\n".'Content-transfer-encoding: 8bit'."\r\n".'Content-type: text/plain; charset='.$lang_common['lang_encoding']."\r\n".'X-Mailer: PunBB Mailer';

    // Make sure all linebreaks are CRLF in message
    $message = str_replace("\n", "\r\n", pun_linebreaks($message));

    if ($pun_config['o_smtp_host'] != '')
        smtp_mail($to, $subject, $message, $headers);
    else
    {
        // Change the linebreaks used in the headers according to OS
        if (strtoupper(substr(PHP_OS, 0, 3)) == 'MAC')
            $headers = str_replace("\r\n", "\r", $headers);
        else if (strtoupper(substr(PHP_OS, 0, 3)) != 'WIN')
            $headers = str_replace("\r\n", "\n", $headers);

        mail($to, $subject, $message, $headers);
    }
}


//
// This function was originally a part of the phpBB Group forum software phpBB2 (http://www.phpbb.com).
// They deserve all the credit for writing it. I made small modifications for it to suit PunBB and it's coding standards.
//
function server_parse($socket, $expected_response)
{
    $server_response = '';
    while (substr($server_response, 3, 1) != ' ')
    {
        if (!($server_response = fgets($socket, 256)))
            error('Couldn\'t get mail server response codes. Please contact the forum administrator.', __FILE__, __LINE__);
    }

    if (!(substr($server_response, 0, 3) == $expected_response))
        error('Unable to send e-mail. Please contact the forum administrator with the following error message reported by the SMTP server: "'.$server_response.'"', __FILE__, __LINE__);
}


//
// This function was originally a part of the phpBB Group forum software phpBB2 (http://www.phpbb.com).
// They deserve all the credit for writing it. I made small modifications for it to suit PunBB and it's coding standards.
//
function smtp_mail($to, $subject, $message, $headers = '')
{
    global $pun_config;

    $recipients = explode(',', $to);

    // Are we using port 25 or a custom port?
    if (strpos($pun_config['o_smtp_host'], ':') !== false)
        list($smtp_host, $smtp_port) = explode(':', $pun_config['o_smtp_host']);
    else
    {
        $smtp_host = $pun_config['o_smtp_host'];
        $smtp_port = 25;
    }

    if (!($socket = fsockopen($smtp_host, $smtp_port, $errno, $errstr, 15)))
        error('Could not connect to smtp host "'.$pun_config['o_smtp_host'].'" ('.$errno.') ('.$errstr.')', __FILE__, __LINE__);

    server_parse($socket, '220');

    if ($pun_config['o_smtp_user'] != '' && $pun_config['o_smtp_pass'] != '')
    {
        fwrite($socket, 'EHLO '.$smtp_host."\r\n");
        server_parse($socket, '250');

        fwrite($socket, 'AUTH LOGIN'."\r\n");
        server_parse($socket, '334');

        fwrite($socket, base64_encode($pun_config['o_smtp_user'])."\r\n");
        server_parse($socket, '334');

        fwrite($socket, base64_encode($pun_config['o_smtp_pass'])."\r\n");
        server_parse($socket, '235');
    }
    else
    {
        fwrite($socket, 'HELO '.$smtp_host."\r\n");
        server_parse($socket, '250');
    }

    fwrite($socket, 'MAIL FROM: <'.$pun_config['o_webmaster_email'].'>'."\r\n");
    server_parse($socket, '250');

    $to_header = 'To: ';

    @reset($recipients);
    while (list(, $email) = @each($recipients))
    {
        fwrite($socket, 'RCPT TO: <'.$email.'>'."\r\n");
        server_parse($socket, '250');

        $to_header .= '<'.$email.'>, ';
    }

    fwrite($socket, 'DATA'."\r\n");
    server_parse($socket, '354');

    fwrite($socket, 'Subject: '.$subject."\r\n".$to_header."\r\n".$headers."\r\n\r\n".$message."\r\n");

    fwrite($socket, '.'."\r\n");
    server_parse($socket, '250');

    fwrite($socket, 'QUIT'."\r\n");
    fclose($socket);

    return true;
}