merge? merge.

[phpbb.git] / phpBB / includes / functions.php

<?php
/**
*
* @package phpBB3
* @version $Id$
* @copyright (c) 2005 phpBB Group
* @license http://opensource.org/licenses/gpl-license.php GNU Public License
*
*/

/**
* @ignore
*/
if (!defined('IN_PHPBB'))
{
        exit;
}

// Common global functions

/**
* set_var
*
* Set variable, used by {@link request_var the request_var function}
*
* @access private
*/
function set_var(&$result, $var, $type, $multibyte = false)
{
        settype($var, $type);
        $result = $var;

        if ($type == 'string')
        {
                $result = trim(htmlspecialchars(str_replace(array("\r\n", "\r"), array("\n", "\n"), $result), ENT_COMPAT, 'UTF-8'));

                if (!empty($result))
                {
                        // Make sure multibyte characters are wellformed
                        if ($multibyte)
                        {
                                if (!preg_match('/^./u', $result))
                                {
                                        $result = '';
                                }
                        }
                        else
                        {
                                // no multibyte, allow only ASCII (0-127)
                                $result = preg_replace('/[\x80-\xFF]/', '?', $result);
                        }
                }

                $result = (STRIP) ? stripslashes($result) : $result;
        }
}

/**
* Central type safe input handling function.
* All variables in GET or POST requests should be retrieved through this
* function to maximise security.
*
* @param        string  $var_name       The name of the variable from the form that is
*                                                               to be retrieved.
* @param        mixed   $default        A default value that is returned if the variable
*                                                               was not set. This function will always return a
*                                                               a value of the same type as the default.
* @param        bool    $multibyte      If $default is a string this paramater has to be
*                                                               true if the variable may contain any UTF-8 characters
*                                                               Default is fault, causing all bytes outside the ASCII
*                                                               range (0-127) to be replaced with question marks
* @param        bool    $cookie         True if the variable shall be retrieved from $_COOKIE
*                                                               instead of $_REQUEST. False by default.
* @return       mixed                           The value of $_REQUEST[$var_name] run through
*                                                               {@link set_var set_var} to ensure that the type is the
*                                                               the same as that of $default. If the variable is not set
*                                                               $default is returned.
*/
function request_var($var_name, $default, $multibyte = false, $cookie = false)
{
        if (!$cookie && isset($_COOKIE[$var_name]))
        {
                if (!isset($_GET[$var_name]) && !isset($_POST[$var_name]))
                {
                        return (is_array($default)) ? array() : $default;
                }
                $_REQUEST[$var_name] = isset($_POST[$var_name]) ? $_POST[$var_name] : $_GET[$var_name];
        }

        if (!isset($_REQUEST[$var_name]) || (is_array($_REQUEST[$var_name]) && !is_array($default)) || (is_array($default) && !is_array($_REQUEST[$var_name])))
        {
                return (is_array($default)) ? array() : $default;
        }

        $var = $_REQUEST[$var_name];
        if (!is_array($default))
        {
                $type = gettype($default);
        }
        else
        {
                list($key_type, $type) = each($default);
                $type = gettype($type);
                $key_type = gettype($key_type);
                if ($type == 'array')
                {
                        reset($default);
                        $default = current($default);
                        list($sub_key_type, $sub_type) = each($default);
                        $sub_type = gettype($sub_type);
                        $sub_type = ($sub_type == 'array') ? 'NULL' : $sub_type;
                        $sub_key_type = gettype($sub_key_type);
                }
        }

        if (is_array($var))
        {
                $_var = $var;
                $var = array();

                foreach ($_var as $k => $v)
                {
                        set_var($k, $k, $key_type);
                        if ($type == 'array' && is_array($v))
                        {
                                foreach ($v as $_k => $_v)
                                {
                                        if (is_array($_v))
                                        {
                                                $_v = null;
                                        }
                                        set_var($_k, $_k, $sub_key_type);
                                        set_var($var[$k][$_k], $_v, $sub_type, $multibyte);
                                }
                        }
                        else
                        {
                                if ($type == 'array' || is_array($v))
                                {
                                        $v = null;
                                }
                                set_var($var[$k], $v, $type, $multibyte);
                        }
                }
        }
        else
        {
                set_var($var, $var, $type, $multibyte);
        }

        return $var;
}

/**
* Checks whether a certain variable was sent via POST.
* To make sure that a request was sent using POST you should call this function
* on at least one variable. The function will perform referrer validation
* as an additional measure against CSRF.
*
* @param        string  $name   The name of the form variable which should have a
*                                                       _p suffix to indicate the check in the code that
*                                                       creates the form too.
* @return       bool                    True if the variable was set in a POST request,
*                                                       false otherwise.
*/
function isset_post($name)
{
        /**
        * @todo validate referrer
        */
        return isset($_POST[$name]);
}

/**
* Set config value. Creates missing config entry.
*/
function set_config($config_name, $config_value, $is_dynamic = false)
{
        global $db, $cache, $config;

        $sql = 'UPDATE ' . CONFIG_TABLE . "
                SET config_value = '" . $db->sql_escape($config_value) . "'
                WHERE config_name = '" . $db->sql_escape($config_name) . "'";
        $db->sql_query($sql);

        if (!$db->sql_affectedrows() && !isset($config[$config_name]))
        {
                $sql = 'INSERT INTO ' . CONFIG_TABLE . ' ' . $db->sql_build_array('INSERT', array(
                        'config_name'   => $config_name,
                        'config_value'  => $config_value,
                        'is_dynamic'    => ($is_dynamic) ? 1 : 0));
                $db->sql_query($sql);
        }

        $config[$config_name] = $config_value;

        if (!$is_dynamic)
        {
                $cache->destroy('config');
        }
}

/**
* Generates an alphanumeric random string of given length
*/
function gen_rand_string($num_chars = 8)
{
        $rand_str = unique_id();
        $rand_str = str_replace('0', 'Z', strtoupper(base_convert($rand_str, 16, 35)));

        return substr($rand_str, 0, $num_chars);
}

/**
* Return unique id
* @param string $extra additional entropy
*/
function unique_id($extra = 'c')
{
        static $dss_seeded = false;
        global $config;

        $val = $config['rand_seed'] . microtime();
        $val = md5($val);
        $config['rand_seed'] = md5($config['rand_seed'] . $val . $extra);

        if ($dss_seeded !== true && ($config['rand_seed_last_update'] < time() - rand(1,10)))
        {
                set_config('rand_seed', $config['rand_seed'], true);
                set_config('rand_seed_last_update', time(), true);
                $dss_seeded = true;
        }

        return substr($val, 4, 16);
}

/**
* Return formatted string for filesizes
*/
function get_formatted_filesize($bytes, $add_size_lang = true)
{
        global $user;

        if ($bytes >= pow(2, 20))
        {
                return ($add_size_lang) ? round($bytes / 1024 / 1024, 2) . ' ' . $user->lang['MIB'] : round($bytes / 1024 / 1024, 2);
        }

        if ($bytes >= pow(2, 10))
        {
                return ($add_size_lang) ? round($bytes / 1024, 2) . ' ' . $user->lang['KIB'] : round($bytes / 1024, 2);
        }

        return ($add_size_lang) ? ($bytes) . ' ' . $user->lang['BYTES'] : ($bytes);
}

/**
* Determine whether we are approaching the maximum execution time. Should be called once
* at the beginning of the script in which it's used.
* @return       bool    Either true if the maximum execution time is nearly reached, or false
*                                       if some time is still left.
*/
function still_on_time($extra_time = 15)
{
        static $max_execution_time, $start_time;

        $time = explode(' ', microtime());
        $current_time = $time[0] + $time[1];

        if (empty($max_execution_time))
        {
                $max_execution_time = (function_exists('ini_get')) ? (int) @ini_get('max_execution_time') : (int) @get_cfg_var('max_execution_time');

                // If zero, then set to something higher to not let the user catch the ten seconds barrier.
                if ($max_execution_time === 0)
                {
                        $max_execution_time = 50 + $extra_time;
                }

                $max_execution_time = min(max(10, ($max_execution_time - $extra_time)), 50);

                // For debugging purposes
                // $max_execution_time = 10;

                global $starttime;
                $start_time = (empty($starttime)) ? $current_time : $starttime;
        }

        return (ceil($current_time - $start_time) < $max_execution_time) ? true : false;
}

/**
*
* @version Version 0.1 / $Id$
*
* Portable PHP password hashing framework.
*
* Written by Solar Designer <solar at openwall.com> in 2004-2006 and placed in
* the public domain.
*
* There's absolutely no warranty.
*
* The homepage URL for this framework is:
*
*       http://www.openwall.com/phpass/
*
* Please be sure to update the Version line if you edit this file in any way.
* It is suggested that you leave the main version number intact, but indicate
* your project name (after the slash) and add your own revision information.
*
* Please do not change the "private" password hashing method implemented in
* here, thereby making your hashes incompatible.  However, if you must, please
* change the hash type identifier (the "$P$") to something different.
*
* Obviously, since this code is in the public domain, the above are not
* requirements (there can be none), but merely suggestions.
*
*
* Hash the password
*/
function phpbb_hash($password)
{
        $itoa64 = './0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';

        $random_state = unique_id();
        $random = '';
        $count = 6;

        if (($fh = @fopen('/dev/urandom', 'rb')))
        {
                $random = fread($fh, $count);
                fclose($fh);
        }

        if (strlen($random) < $count)
        {
                $random = '';

                for ($i = 0; $i < $count; $i += 16)
                {
                        $random_state = md5(unique_id() . $random_state);
                        $random .= pack('H*', md5($random_state));
                }
                $random = substr($random, 0, $count);
        }

        $hash = _hash_crypt_private($password, _hash_gensalt_private($random, $itoa64), $itoa64);

        if (strlen($hash) == 34)
        {
                return $hash;
        }

        return md5($password);
}

/**
* Check for correct password
*/
function phpbb_check_hash($password, $hash)
{
        $itoa64 = './0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz';
        if (strlen($hash) == 34)
        {
                return (_hash_crypt_private($password, $hash, $itoa64) === $hash) ? true : false;
        }

        return (md5($password) === $hash) ? true : false;
}

/**
* Generate salt for hash generation
*/
function _hash_gensalt_private($input, &$itoa64, $iteration_count_log2 = 6)
{
        if ($iteration_count_log2 < 4 || $iteration_count_log2 > 31)
        {
                $iteration_count_log2 = 8;
        }

        $output = '$H$';
        $output .= $itoa64[min($iteration_count_log2 + 5, 30)];
        $output .= _hash_encode64($input, 6, $itoa64);

        return $output;
}

/**
* Encode hash
*/
function _hash_encode64($input, $count, &$itoa64)
{
        $output = '';
        $i = 0;

        do
        {
                $value = ord($input[$i++]);
                $output .= $itoa64[$value & 0x3f];

                if ($i < $count)
                {
                        $value |= ord($input[$i]) << 8;
                }

                $output .= $itoa64[($value >> 6) & 0x3f];

                if ($i++ >= $count)
                {
                        break;
                }

                if ($i < $count)
                {
                        $value |= ord($input[$i]) << 16;
                }

                $output .= $itoa64[($value >> 12) & 0x3f];

                if ($i++ >= $count)
                {
                        break;
                }

                $output .= $itoa64[($value >> 18) & 0x3f];
        }
        while ($i < $count);

        return $output;
}

/**
* The crypt function/replacement
*/
function _hash_crypt_private($password, $setting, &$itoa64)
{
        $output = '*';

        // Check for correct hash
        if (substr($setting, 0, 3) != '$H$')
        {
                return $output;
        }

        $count_log2 = strpos($itoa64, $setting[3]);

        if ($count_log2 < 7 || $count_log2 > 30)
        {
                return $output;
        }

        $count = 1 << $count_log2;
        $salt = substr($setting, 4, 8);

        if (strlen($salt) != 8)
        {
                return $output;
        }

        /**
        * We're kind of forced to use MD5 here since it's the only
        * cryptographic primitive available in all versions of PHP
        * currently in use.  To implement our own low-level crypto
        * in PHP would result in much worse performance and
        * consequently in lower iteration counts and hashes that are
        * quicker to crack (by non-PHP code).
        */
        $hash = md5($salt . $password, true);
        do
        {
                $hash = md5($hash . $password, true);
        }
        while (--$count);

        $output = substr($setting, 0, 12);
        $output .= _hash_encode64($hash, 16, $itoa64);

        return $output;
}

/**
* Checks if a path ($path) is absolute or relative
*
* @param string $path Path to check absoluteness of
* @return boolean
*/
function is_absolute($path)
{
        return ($path[0] == '/' || (DIRECTORY_SEPARATOR == '\\' && preg_match('#^[a-z]:/#i', $path))) ? true : false;
}

/**
* @author Chris Smith <chris@project-minerva.org>
* @copyright 2006 Project Minerva Team
* @param string $path The path which we should attempt to resolve.
* @return mixed
*/
function phpbb_own_realpath($path)
{
        // Now to perform funky shizzle

        // Switch to use UNIX slashes
        $path = str_replace(DIRECTORY_SEPARATOR, '/', $path);
        $path_prefix = '';

        // Determine what sort of path we have
        if (is_absolute($path))
        {
                $absolute = true;

                if ($path[0] == '/')
                {
                        // Absolute path, *NIX style
                        $path_prefix = '';
                }
                else
                {
                        // Absolute path, Windows style
                        // Remove the drive letter and colon
                        $path_prefix = $path[0] . ':';
                        $path = substr($path, 2);
                }
        }
        else
        {
                // Relative Path
                // Prepend the current working directory
                if (function_exists('getcwd'))
                {
                        // This is the best method, hopefully it is enabled!
                        $path = str_replace(DIRECTORY_SEPARATOR, '/', getcwd()) . '/' . $path;
                        $absolute = true;
                        if (preg_match('#^[a-z]:#i', $path))
                        {
                                $path_prefix = $path[0] . ':';
                                $path = substr($path, 2);
                        }
                        else
                        {
                                $path_prefix = '';
                        }
                }
                else if (isset($_SERVER['SCRIPT_FILENAME']) && !empty($_SERVER['SCRIPT_FILENAME']))
                {
                        // Warning: If chdir() has been used this will lie!
                        // Warning: This has some problems sometime (CLI can create them easily)
                        $path = str_replace(DIRECTORY_SEPARATOR, '/', dirname($_SERVER['SCRIPT_FILENAME'])) . '/' . $path;
                        $absolute = true;
                        $path_prefix = '';
                }
                else
                {
                        // We have no way of getting the absolute path, just run on using relative ones.
                        $absolute = false;
                        $path_prefix = '.';
                }
        }

        // Remove any repeated slashes
        $path = preg_replace('#/{2,}#', '/', $path);

        // Remove the slashes from the start and end of the path
        $path = trim($path, '/');

        // Break the string into little bits for us to nibble on
        $bits = explode('/', $path);

        // Remove any . in the path, renumber array for the loop below
        $bits = array_values(array_diff($bits, array('.')));

        // Lets get looping, run over and resolve any .. (up directory)
        for ($i = 0, $max = sizeof($bits); $i < $max; $i++)
        {
                // @todo Optimise
                if ($bits[$i] == '..' )
                {
                        if (isset($bits[$i - 1]))
                        {
                                if ($bits[$i - 1] != '..')
                                {
                                        // We found a .. and we are able to traverse upwards, lets do it!
                                        unset($bits[$i]);
                                        unset($bits[$i - 1]);
                                        $i -= 2;
                                        $max -= 2;
                                        $bits = array_values($bits);
                                }
                        }
                        else if ($absolute) // ie. !isset($bits[$i - 1]) && $absolute
                        {
                                // We have an absolute path trying to descend above the root of the filesystem
                                // ... Error!
                                return false;
                        }
                }
        }

        // Prepend the path prefix
        array_unshift($bits, $path_prefix);

        $resolved = '';

        $max = sizeof($bits) - 1;

        // Check if we are able to resolve symlinks, Windows cannot.
        $symlink_resolve = (function_exists('readlink')) ? true : false;

        foreach ($bits as $i => $bit)
        {
                if (@is_dir("$resolved/$bit") || ($i == $max && @is_file("$resolved/$bit")))
                {
                        // Path Exists
                        if ($symlink_resolve && is_link("$resolved/$bit") && ($link = readlink("$resolved/$bit")))
                        {
                                // Resolved a symlink.
                                $resolved = $link . (($i == $max) ? '' : '/');
                                continue;
                        }
                }
                else
                {
                        // Something doesn't exist here!
                        // This is correct realpath() behaviour but sadly open_basedir and safe_mode make this problematic
                        // return false;
                }
                $resolved .= $bit . (($i == $max) ? '' : '/');
        }

        // @todo If the file exists fine and open_basedir only has one path we should be able to prepend it
        // because we must be inside that basedir, the question is where...
        // @internal The slash in is_dir() gets around an open_basedir restriction
        if (!@file_exists($resolved) || (!is_dir($resolved . '/') && !is_file($resolved)))
        {
                return false;
        }

        // Put the slashes back to the native operating systems slashes
        $resolved = str_replace('/', DIRECTORY_SEPARATOR, $resolved);

        // Check for DIRECTORY_SEPARATOR at the end (and remove it!)
        if (substr($resolved, -1) == DIRECTORY_SEPARATOR)
        {
                return substr($resolved, 0, -1);
        }

        return $resolved; // We got here, in the end!
}

if (!function_exists('realpath'))
{
        /**
        * A wrapper for realpath
        * @ignore
        */
        function phpbb_realpath($path)
        {
                return phpbb_own_realpath($path);
        }
}
else
{
        /**
        * A wrapper for realpath
        */
        function phpbb_realpath($path)
        {
                $realpath = realpath($path);

                // Strangely there are provider not disabling realpath but returning strange values. :o
                // We at least try to cope with them.
                if ($realpath === $path || $realpath === false)
                {
                        return phpbb_own_realpath($path);
                }

                // Check for DIRECTORY_SEPARATOR at the end (and remove it!)
                if (substr($realpath, -1) == DIRECTORY_SEPARATOR)
                {
                        $realpath = substr($realpath, 0, -1);
                }

                return $realpath;
        }
}

// functions used for building option fields

/**
* Pick a language, any language ...
*/
function language_select($default = '')
{
        global $db;

        $sql = 'SELECT lang_iso, lang_local_name
                FROM ' . LANG_TABLE . '
                ORDER BY lang_english_name';
        $result = $db->sql_query($sql);

        $lang_options = '';
        while ($row = $db->sql_fetchrow($result))
        {
                $selected = ($row['lang_iso'] == $default) ? ' selected="selected"' : '';
                $lang_options .= '<option value="' . $row['lang_iso'] . '"' . $selected . '>' . $row['lang_local_name'] . '</option>';
        }
        $db->sql_freeresult($result);

        return $lang_options;
}

/**
* Pick a template/theme combo,
*/
function style_select($default = '', $all = false)
{
        global $db;

        $sql_where = (!$all) ? 'WHERE style_active = 1 ' : '';
        $sql = 'SELECT style_id, style_name
                FROM ' . STYLES_TABLE . "
                $sql_where
                ORDER BY style_name";
        $result = $db->sql_query($sql);

        $style_options = '';
        while ($row = $db->sql_fetchrow($result))
        {
                $selected = ($row['style_id'] == $default) ? ' selected="selected"' : '';
                $style_options .= '<option value="' . $row['style_id'] . '"' . $selected . '>' . $row['style_name'] . '</option>';
        }
        $db->sql_freeresult($result);

        return $style_options;
}

/**
* Pick a timezone
*/
function tz_select($default = '', $truncate = false)
{
        global $user;

        $tz_select = '';
        foreach ($user->lang['tz_zones'] as $offset => $zone)
        {
                if ($truncate)
                {
                        $zone_trunc = truncate_string($zone, 50, 255, false, '...');
                }
                else
                {
                        $zone_trunc = $zone;
                }

                if (is_numeric($offset))
                {
                        $selected = ($offset == $default) ? ' selected="selected"' : '';
                        $tz_select .= '<option title="'.$zone.'" value="' . $offset . '"' . $selected . '>' . $zone_trunc . '</option>';
                }
        }

        return $tz_select;
}

// Functions handling topic/post tracking/marking

/**
* Marks a topic/forum as read
* Marks a topic as posted to
*
* @param int $user_id can only be used with $mode == 'post'
*/
function markread($mode, $forum_id = false, $topic_id = false, $post_time = 0, $user_id = 0)
{
        global $db, $user, $config;

        if ($mode == 'all')
        {
                if ($forum_id === false || !sizeof($forum_id))
                {
                        if ($config['load_db_lastread'] && $user->data['is_registered'])
                        {
                                // Mark all forums read (index page)
                                $db->sql_query('DELETE FROM ' . TOPICS_TRACK_TABLE . " WHERE user_id = {$user->data['user_id']}");
                                $db->sql_query('DELETE FROM ' . FORUMS_TRACK_TABLE . " WHERE user_id = {$user->data['user_id']}");
                                $db->sql_query('UPDATE ' . USERS_TABLE . ' SET user_lastmark = ' . time() . " WHERE user_id = {$user->data['user_id']}");
                        }
                        else if ($config['load_anon_lastread'] || $user->data['is_registered'])
                        {
                                $tracking_topics = (isset($_COOKIE[$config['cookie_name'] . '_track'])) ? ((STRIP) ? stripslashes($_COOKIE[$config['cookie_name'] . '_track']) : $_COOKIE[$config['cookie_name'] . '_track']) : '';
                                $tracking_topics = ($tracking_topics) ? tracking_unserialize($tracking_topics) : array();

                                unset($tracking_topics['tf']);
                                unset($tracking_topics['t']);
                                unset($tracking_topics['f']);
                                $tracking_topics['l'] = base_convert(time() - $config['board_startdate'], 10, 36);

                                $user->set_cookie('track', tracking_serialize($tracking_topics), time() + 31536000);
                                $_COOKIE[$config['cookie_name'] . '_track'] = (STRIP) ? addslashes(tracking_serialize($tracking_topics)) : tracking_serialize($tracking_topics);

                                unset($tracking_topics);

                                if ($user->data['is_registered'])
                                {
                                        $db->sql_query('UPDATE ' . USERS_TABLE . ' SET user_lastmark = ' . time() . " WHERE user_id = {$user->data['user_id']}");
                                }
                        }
                }

                return;
        }
        else if ($mode == 'topics')
        {
                // Mark all topics in forums read
                if (!is_array($forum_id))
                {
                        $forum_id = array($forum_id);
                }

                // Add 0 to forums array to mark global announcements correctly
                $forum_id[] = 0;

                if ($config['load_db_lastread'] && $user->data['is_registered'])
                {
                        $sql = 'DELETE FROM ' . TOPICS_TRACK_TABLE . "
                                WHERE user_id = {$user->data['user_id']}
                                        AND " . $db->sql_in_set('forum_id', $forum_id);
                        $db->sql_query($sql);

                        $sql = 'SELECT forum_id
                                FROM ' . FORUMS_TRACK_TABLE . "
                                WHERE user_id = {$user->data['user_id']}
                                        AND " . $db->sql_in_set('forum_id', $forum_id);
                        $result = $db->sql_query($sql);

                        $sql_update = array();
                        while ($row = $db->sql_fetchrow($result))
                        {
                                $sql_update[] = $row['forum_id'];
                        }
                        $db->sql_freeresult($result);

                        if (sizeof($sql_update))
                        {
                                $sql = 'UPDATE ' . FORUMS_TRACK_TABLE . '
                                        SET mark_time = ' . time() . "
                                        WHERE user_id = {$user->data['user_id']}
                                                AND " . $db->sql_in_set('forum_id', $sql_update);
                                $db->sql_query($sql);
                        }

                        if ($sql_insert = array_diff($forum_id, $sql_update))
                        {
                                $sql_ary = array();
                                foreach ($sql_insert as $f_id)
                                {
                                        $sql_ary[] = array(
                                                'user_id'       => (int) $user->data['user_id'],
                                                'forum_id'      => (int) $f_id,
                                                'mark_time'     => time()
                                        );
                                }

                                $db->sql_multi_insert(FORUMS_TRACK_TABLE, $sql_ary);
                        }
                }
                else if ($config['load_anon_lastread'] || $user->data['is_registered'])
                {
                        $tracking = (isset($_COOKIE[$config['cookie_name'] . '_track'])) ? ((STRIP) ? stripslashes($_COOKIE[$config['cookie_name'] . '_track']) : $_COOKIE[$config['cookie_name'] . '_track']) : '';
                        $tracking = ($tracking) ? tracking_unserialize($tracking) : array();

                        foreach ($forum_id as $f_id)
                        {
                                $topic_ids36 = (isset($tracking['tf'][$f_id])) ? $tracking['tf'][$f_id] : array();

                                if (isset($tracking['tf'][$f_id]))
                                {
                                        unset($tracking['tf'][$f_id]);
                                }

                                foreach ($topic_ids36 as $topic_id36)
                                {
                                        unset($tracking['t'][$topic_id36]);
                                }

                                if (isset($tracking['f'][$f_id]))
                                {
                                        unset($tracking['f'][$f_id]);
                                }

                                $tracking['f'][$f_id] = base_convert(time() - $config['board_startdate'], 10, 36);
                        }

                        if (isset($tracking['tf']) && empty($tracking['tf']))
                        {
                                unset($tracking['tf']);
                        }

                        $user->set_cookie('track', tracking_serialize($tracking), time() + 31536000);
                        $_COOKIE[$config['cookie_name'] . '_track'] = (STRIP) ? addslashes(tracking_serialize($tracking)) : tracking_serialize($tracking);

                        unset($tracking);
                }

                return;
        }
        else if ($mode == 'topic')
        {
                if ($topic_id === false || $forum_id === false)
                {
                        return;
                }

                if ($config['load_db_lastread'] && $user->data['is_registered'])
                {
                        $sql = 'UPDATE ' . TOPICS_TRACK_TABLE . '
                                SET mark_time = ' . (($post_time) ? $post_time : time()) . "
                                WHERE user_id = {$user->data['user_id']}
                                        AND topic_id = $topic_id";
                        $db->sql_query($sql);

                        // insert row
                        if (!$db->sql_affectedrows())
                        {
                                $db->sql_return_on_error(true);

                                $sql_ary = array(
                                        'user_id'               => (int) $user->data['user_id'],
                                        'topic_id'              => (int) $topic_id,
                                        'forum_id'              => (int) $forum_id,
                                        'mark_time'             => ($post_time) ? (int) $post_time : time(),
                                );

                                $db->sql_query('INSERT INTO ' . TOPICS_TRACK_TABLE . ' ' . $db->sql_build_array('INSERT', $sql_ary));

                                $db->sql_return_on_error(false);
                        }
                }
                else if ($config['load_anon_lastread'] || $user->data['is_registered'])
                {
                        $tracking = (isset($_COOKIE[$config['cookie_name'] . '_track'])) ? ((STRIP) ? stripslashes($_COOKIE[$config['cookie_name'] . '_track']) : $_COOKIE[$config['cookie_name'] . '_track']) : '';
                        $tracking = ($tracking) ? tracking_unserialize($tracking) : array();

                        $topic_id36 = base_convert($topic_id, 10, 36);

                        if (!isset($tracking['t'][$topic_id36]))
                        {
                                $tracking['tf'][$forum_id][$topic_id36] = true;
                        }

                        $post_time = ($post_time) ? $post_time : time();
                        $tracking['t'][$topic_id36] = base_convert($post_time - $config['board_startdate'], 10, 36);

                        // If the cookie grows larger than 10000 characters we will remove the smallest value
                        // This can result in old topics being unread - but most of the time it should be accurate...
                        if (isset($_COOKIE[$config['cookie_name'] . '_track']) && strlen($_COOKIE[$config['cookie_name'] . '_track']) > 10000)
                        {
                                //echo 'Cookie grown too large' . print_r($tracking, true);

                                // We get the ten most minimum stored time offsets and its associated topic ids
                                $time_keys = array();
                                for ($i = 0; $i < 10 && sizeof($tracking['t']); $i++)
                                {
                                        $min_value = min($tracking['t']);
                                        $m_tkey = array_search($min_value, $tracking['t']);
                                        unset($tracking['t'][$m_tkey]);

                                        $time_keys[$m_tkey] = $min_value;
                                }

                                // Now remove the topic ids from the array...
                                foreach ($tracking['tf'] as $f_id => $topic_id_ary)
                                {
                                        foreach ($time_keys as $m_tkey => $min_value)
                                        {
                                                if (isset($topic_id_ary[$m_tkey]))
                                                {
                                                        $tracking['f'][$f_id] = $min_value;
                                                        unset($tracking['tf'][$f_id][$m_tkey]);
                                                }
                                        }
                                }

                                if ($user->data['is_registered'])
                                {
                                        $user->data['user_lastmark'] = intval(base_convert(max($time_keys) + $config['board_startdate'], 36, 10));
                                        $db->sql_query('UPDATE ' . USERS_TABLE . ' SET user_lastmark = ' . $user->data['user_lastmark'] . " WHERE user_id = {$user->data['user_id']}");
                                }
                                else
                                {
                                        $tracking['l'] = max($time_keys);
                                }
                        }

                        $user->set_cookie('track', tracking_serialize($tracking), time() + 31536000);
                        $_COOKIE[$config['cookie_name'] . '_track'] = (STRIP) ? addslashes(tracking_serialize($tracking)) : tracking_serialize($tracking);
                }

                return;
        }
        else if ($mode == 'post')
        {
                if ($topic_id === false)
                {
                        return;
                }

                $use_user_id = (!$user_id) ? $user->data['user_id'] : $user_id;

                if ($config['load_db_track'] && $use_user_id != ANONYMOUS)
                {
                        $db->sql_return_on_error(true);

                        $sql_ary = array(
                                'user_id'               => (int) $use_user_id,
                                'topic_id'              => (int) $topic_id,
                                'topic_posted'  => 1
                        );

                        $db->sql_query('INSERT INTO ' . TOPICS_POSTED_TABLE . ' ' . $db->sql_build_array('INSERT', $sql_ary));

                        $db->sql_return_on_error(false);
                }

                return;
        }
}

/**
* Get topic tracking info by using already fetched info
*/
function get_topic_tracking($forum_id, $topic_ids, &$rowset, $forum_mark_time, $global_announce_list = false)
{
        global $config, $user;

        $last_read = array();

        if (!is_array($topic_ids))
        {
                $topic_ids = array($topic_ids);
        }

        foreach ($topic_ids as $topic_id)
        {
                if (!empty($rowset[$topic_id]['mark_time']))
                {
                        $last_read[$topic_id] = $rowset[$topic_id]['mark_time'];
                }
        }

        $topic_ids = array_diff($topic_ids, array_keys($last_read));

        if (sizeof($topic_ids))
        {
                $mark_time = array();

                // Get global announcement info
                if ($global_announce_list && sizeof($global_announce_list))
                {
                        if (!isset($forum_mark_time[0]))
                        {
                                global $db;

                                $sql = 'SELECT mark_time
                                        FROM ' . FORUMS_TRACK_TABLE . "
                                        WHERE user_id = {$user->data['user_id']}
                                                AND forum_id = 0";
                                $result = $db->sql_query($sql);
                                $row = $db->sql_fetchrow($result);
                                $db->sql_freeresult($result);

                                if ($row)
                                {
                                        $mark_time[0] = $row['mark_time'];
                                }
                        }
                        else
                        {
                                if ($forum_mark_time[0] !== false)
                                {
                                        $mark_time[0] = $forum_mark_time[0];
                                }
                        }
                }

                if (!empty($forum_mark_time[$forum_id]) && $forum_mark_time[$forum_id] !== false)
                {
                        $mark_time[$forum_id] = $forum_mark_time[$forum_id];
                }

                $user_lastmark = (isset($mark_time[$forum_id])) ? $mark_time[$forum_id] : $user->data['user_lastmark'];

                foreach ($topic_ids as $topic_id)
                {
                        if ($global_announce_list && isset($global_announce_list[$topic_id]))
                        {
                                $last_read[$topic_id] = (isset($mark_time[0])) ? $mark_time[0] : $user_lastmark;
                        }
                        else
                        {
                                $last_read[$topic_id] = $user_lastmark;
                        }
                }
        }

        return $last_read;
}

/**
* Get topic tracking info from db (for cookie based tracking only this function is used)
*/
function get_complete_topic_tracking($forum_id, $topic_ids, $global_announce_list = false)
{
        global $config, $user;

        $last_read = array();

        if (!is_array($topic_ids))
        {
                $topic_ids = array($topic_ids);
        }

        if ($config['load_db_lastread'] && $user->data['is_registered'])
        {
                global $db;

                $sql = 'SELECT topic_id, mark_time
                        FROM ' . TOPICS_TRACK_TABLE . "
                        WHERE user_id = {$user->data['user_id']}
                                AND " . $db->sql_in_set('topic_id', $topic_ids);
                $result = $db->sql_query($sql);

                while ($row = $db->sql_fetchrow($result))
                {
                        $last_read[$row['topic_id']] = $row['mark_time'];
                }
                $db->sql_freeresult($result);

                $topic_ids = array_diff($topic_ids, array_keys($last_read));

                if (sizeof($topic_ids))
                {
                        $sql = 'SELECT forum_id, mark_time
                                FROM ' . FORUMS_TRACK_TABLE . "
                                WHERE user_id = {$user->data['user_id']}
                                        AND forum_id " .
                                        (($global_announce_list && sizeof($global_announce_list)) ? "IN (0, $forum_id)" : "= $forum_id");
                        $result = $db->sql_query($sql);

                        $mark_time = array();
                        while ($row = $db->sql_fetchrow($result))
                        {
                                $mark_time[$row['forum_id']] = $row['mark_time'];
                        }
                        $db->sql_freeresult($result);

                        $user_lastmark = (isset($mark_time[$forum_id])) ? $mark_time[$forum_id] : $user->data['user_lastmark'];

                        foreach ($topic_ids as $topic_id)
                        {
                                if ($global_announce_list && isset($global_announce_list[$topic_id]))
                                {
                                        $last_read[$topic_id] = (isset($mark_time[0])) ? $mark_time[0] : $user_lastmark;
                                }
                                else
                                {
                                        $last_read[$topic_id] = $user_lastmark;
                                }
                        }
                }
        }
        else if ($config['load_anon_lastread'] || $user->data['is_registered'])
        {
                global $tracking_topics;

                if (!isset($tracking_topics) || !sizeof($tracking_topics))
                {
                        $tracking_topics = (isset($_COOKIE[$config['cookie_name'] . '_track'])) ? ((STRIP) ? stripslashes($_COOKIE[$config['cookie_name'] . '_track']) : $_COOKIE[$config['cookie_name'] . '_track']) : '';
                        $tracking_topics = ($tracking_topics) ? tracking_unserialize($tracking_topics) : array();
                }

                if (!$user->data['is_registered'])
                {
                        $user_lastmark = (isset($tracking_topics['l'])) ? base_convert($tracking_topics['l'], 36, 10) + $config['board_startdate'] : 0;
                }
                else
                {
                        $user_lastmark = $user->data['user_lastmark'];
                }

                foreach ($topic_ids as $topic_id)
                {
                        $topic_id36 = base_convert($topic_id, 10, 36);

                        if (isset($tracking_topics['t'][$topic_id36]))
                        {
                                $last_read[$topic_id] = base_convert($tracking_topics['t'][$topic_id36], 36, 10) + $config['board_startdate'];
                        }
                }

                $topic_ids = array_diff($topic_ids, array_keys($last_read));

                if (sizeof($topic_ids))
                {
                        $mark_time = array();
                        if ($global_announce_list && sizeof($global_announce_list))
                        {
                                if (isset($tracking_topics['f'][0]))
                                {
                                        $mark_time[0] = base_convert($tracking_topics['f'][0], 36, 10) + $config['board_startdate'];
                                }
                        }

                        if (isset($tracking_topics['f'][$forum_id]))
                        {
                                $mark_time[$forum_id] = base_convert($tracking_topics['f'][$forum_id], 36, 10) + $config['board_startdate'];
                        }

                        $user_lastmark = (isset($mark_time[$forum_id])) ? $mark_time[$forum_id] : $user_lastmark;

                        foreach ($topic_ids as $topic_id)
                        {
                                if ($global_announce_list && isset($global_announce_list[$topic_id]))
                                {
                                        $last_read[$topic_id] = (isset($mark_time[0])) ? $mark_time[0] : $user_lastmark;
                                }
                                else
                                {
                                        $last_read[$topic_id] = $user_lastmark;
                                }
                        }
                }
        }

        return $last_read;
}

/**
* Check for read forums and update topic tracking info accordingly
*
* @param int $forum_id the forum id to check
* @param int $forum_last_post_time the forums last post time
* @param int $f_mark_time the forums last mark time if user is registered and load_db_lastread enabled
* @param int $mark_time_forum false if the mark time needs to be obtained, else the last users forum mark time
*
* @return true if complete forum got marked read, else false.
*/
function update_forum_tracking_info($forum_id, $forum_last_post_time, $f_mark_time = false, $mark_time_forum = false)
{
        global $db, $tracking_topics, $user, $config;

        // Determine the users last forum mark time if not given.
        if ($mark_time_forum === false)
        {
                if ($config['load_db_lastread'] && $user->data['is_registered'])
                {
                        $mark_time_forum = (!empty($f_mark_time)) ? $f_mark_time : $user->data['user_lastmark'];
                }
                else if ($config['load_anon_lastread'] || $user->data['is_registered'])
                {
                        $tracking_topics = (isset($_COOKIE[$config['cookie_name'] . '_track'])) ? ((STRIP) ? stripslashes($_COOKIE[$config['cookie_name'] . '_track']) : $_COOKIE[$config['cookie_name'] . '_track']) : '';
                        $tracking_topics = ($tracking_topics) ? tracking_unserialize($tracking_topics) : array();

                        if (!$user->data['is_registered'])
                        {
                                $user->data['user_lastmark'] = (isset($tracking_topics['l'])) ? (int) (base_convert($tracking_topics['l'], 36, 10) + $config['board_startdate']) : 0;
                        }

                        $mark_time_forum = (isset($tracking_topics['f'][$forum_id])) ? (int) (base_convert($tracking_topics['f'][$forum_id], 36, 10) + $config['board_startdate']) : $user->data['user_lastmark'];
                }
        }

        // Check the forum for any left unread topics.
        // If there are none, we mark the forum as read.
        if ($config['load_db_lastread'] && $user->data['is_registered'])
        {
                if ($mark_time_forum >= $forum_last_post_time)
                {
                        // We do not need to mark read, this happened before. Therefore setting this to true
                        $row = true;
                }
                else
                {
                        $sql = 'SELECT t.forum_id FROM ' . TOPICS_TABLE . ' t
                                LEFT JOIN ' . TOPICS_TRACK_TABLE . ' tt ON (tt.topic_id = t.topic_id AND tt.user_id = ' . $user->data['user_id'] . ')
                                WHERE t.forum_id = ' . $forum_id . '
                                        AND t.topic_last_post_time > ' . $mark_time_forum . '
                                        AND t.topic_moved_id = 0
                                        AND (tt.topic_id IS NULL OR tt.mark_time < t.topic_last_post_time)
                                GROUP BY t.forum_id';
                        $result = $db->sql_query_limit($sql, 1);
                        $row = $db->sql_fetchrow($result);
                        $db->sql_freeresult($result);
                }
        }
        else if ($config['load_anon_lastread'] || $user->data['is_registered'])
        {
                // Get information from cookie
                $row = false;

                if (!isset($tracking_topics['tf'][$forum_id]))
                {
                        // We do not need to mark read, this happened before. Therefore setting this to true
                        $row = true;
                }
                else
                {
                        $sql = 'SELECT topic_id
                                FROM ' . TOPICS_TABLE . '
                                WHERE forum_id = ' . $forum_id . '
                                        AND topic_last_post_time > ' . $mark_time_forum . '
                                        AND topic_moved_id = 0';
                        $result = $db->sql_query($sql);

                        $check_forum = $tracking_topics['tf'][$forum_id];
                        $unread = false;

                        while ($row = $db->sql_fetchrow($result))
                        {
                                if (!isset($check_forum[base_convert($row['topic_id'], 10, 36)]))
                                {
                                        $unread = true;
                                        break;
                                }
                        }
                        $db->sql_freeresult($result);

                        $row = $unread;
                }
        }
        else
        {
                $row = true;
        }

        if (!$row)
        {
                markread('topics', $forum_id);
                return true;
        }

        return false;
}

/**
* Transform an array into a serialized format
*/
function tracking_serialize($input)
{
        $out = '';
        foreach ($input as $key => $value)
        {
                if (is_array($value))
                {
                        $out .= $key . ':(' . tracking_serialize($value) . ');';
                }
                else
                {
                        $out .= $key . ':' . $value . ';';
                }
        }
        return $out;
}

/**
* Transform a serialized array into an actual array
*/
function tracking_unserialize($string, $max_depth = 3)
{
        $n = strlen($string);
        if ($n > 10010)
        {
                die('Invalid data supplied');
        }
        $data = $stack = array();
        $key = '';
        $mode = 0;
        $level = &$data;
        for ($i = 0; $i < $n; ++$i)
        {
                switch ($mode)
                {
                        case 0:
                                switch ($string[$i])
                                {
                                        case ':':
                                                $level[$key] = 0;
                                                $mode = 1;
                                        break;
                                        case ')':
                                                unset($level);
                                                $level = array_pop($stack);
                                                $mode = 3;
                                        break;
                                        default:
                                                $key .= $string[$i];
                                }
                        break;

                        case 1:
                                switch ($string[$i])
                                {
                                        case '(':
                                                if (sizeof($stack) >= $max_depth)
                                                {
                                                        die('Invalid data supplied');
                                                }
                                                $stack[] = &$level;
                                                $level[$key] = array();
                                                $level = &$level[$key];
                                                $key = '';
                                                $mode = 0;
                                        break;
                                        default:
                                                $level[$key] = $string[$i];
                                                $mode = 2;
                                        break;
                                }
                        break;

                        case 2:
                                switch ($string[$i])
                                {
                                        case ')':
                                                unset($level);
                                                $level = array_pop($stack);
                                                $mode = 3;
                                        break;
                                        case ';':
                                                $key = '';
                                                $mode = 0;
                                        break;
                                        default:
                                                $level[$key] .= $string[$i];
                                        break;
                                }
                        break;

                        case 3:
                                switch ($string[$i])
                                {
                                        case ')':
                                                unset($level);
                                                $level = array_pop($stack);
                                        break;
                                        case ';':
                                                $key = '';
                                                $mode = 0;
                                        break;
                                        default:
                                                die('Invalid data supplied');
                                        break;
                                }
                        break;
                }
        }

        if (sizeof($stack) != 0 || ($mode != 0 && $mode != 3))
        {
                die('Invalid data supplied');
        }

        return $level;
}

// Pagination functions

/**
* Pagination routine, generates page number sequence
* tpl_prefix is for using different pagination blocks at one page
*/
function generate_pagination($base_url, $num_items, $per_page, $start_item, $add_prevnext_text = false, $tpl_prefix = '')
{
        global $template, $user;

        // Make sure $per_page is a valid value
        $per_page = ($per_page <= 0) ? 1 : $per_page;

        $seperator = '<span class="page-sep">' . $user->lang['COMMA_SEPARATOR'] . '</span>';
        $total_pages = ceil($num_items / $per_page);

        if ($total_pages == 1 || !$num_items)
        {
                return false;
        }

        $on_page = floor($start_item / $per_page) + 1;
        $url_delim = (strpos($base_url, '?') === false) ? '?' : '&amp;';

        $page_string = ($on_page == 1) ? '<strong>1</strong>' : '<a href="' . $base_url . '">1</a>';

        if ($total_pages > 5)
        {
                $start_cnt = min(max(1, $on_page - 4), $total_pages - 5);
                $end_cnt = max(min($total_pages, $on_page + 4), 6);

                $page_string .= ($start_cnt > 1) ? ' ... ' : $seperator;

                for ($i = $start_cnt + 1; $i < $end_cnt; $i++)
                {
                        $page_string .= ($i == $on_page) ? '<strong>' . $i . '</strong>' : '<a href="' . $base_url . "{$url_delim}start=" . (($i - 1) * $per_page) . '">' . $i . '</a>';
                        if ($i < $end_cnt - 1)
                        {
                                $page_string .= $seperator;
                        }
                }

                $page_string .= ($end_cnt < $total_pages) ? ' ... ' : $seperator;
        }
        else
        {
                $page_string .= $seperator;

                for ($i = 2; $i < $total_pages; $i++)
                {
                        $page_string .= ($i == $on_page) ? '<strong>' . $i . '</strong>' : '<a href="' . $base_url . "{$url_delim}start=" . (($i - 1) * $per_page) . '">' . $i . '</a>';
                        if ($i < $total_pages)
                        {
                                $page_string .= $seperator;
                        }
                }
        }

        $page_string .= ($on_page == $total_pages) ? '<strong>' . $total_pages . '</strong>' : '<a href="' . $base_url . "{$url_delim}start=" . (($total_pages - 1) * $per_page) . '">' . $total_pages . '</a>';

        if ($add_prevnext_text)
        {
                if ($on_page != 1)
                {
                        $page_string = '<a href="' . $base_url . "{$url_delim}start=" . (($on_page - 2) * $per_page) . '">' . $user->lang['PREVIOUS'] . '</a>&nbsp;&nbsp;' . $page_string;
                }

                if ($on_page != $total_pages)
                {
                        $page_string .= '&nbsp;&nbsp;<a href="' . $base_url . "{$url_delim}start=" . ($on_page * $per_page) . '">' . $user->lang['NEXT'] . '</a>';
                }
        }

        $template->assign_vars(array(
                $tpl_prefix . 'BASE_URL'                => $base_url,
                'A_' . $tpl_prefix . 'BASE_URL' => addslashes($base_url),
                $tpl_prefix . 'PER_PAGE'                => $per_page,

                $tpl_prefix . 'PREVIOUS_PAGE'   => ($on_page == 1) ? '' : $base_url . "{$url_delim}start=" . (($on_page - 2) * $per_page),
                $tpl_prefix . 'NEXT_PAGE'               => ($on_page == $total_pages) ? '' : $base_url . "{$url_delim}start=" . ($on_page * $per_page),
                $tpl_prefix . 'TOTAL_PAGES'             => $total_pages,
        ));

        return $page_string;
}

/**
* Return current page (pagination)
*/
function on_page($num_items, $per_page, $start)
{
        global $template, $user;

        // Make sure $per_page is a valid value
        $per_page = ($per_page <= 0) ? 1 : $per_page;

        $on_page = floor($start / $per_page) + 1;

        $template->assign_vars(array(
                'ON_PAGE'               => $on_page)
        );

        return sprintf($user->lang['PAGE_OF'], $on_page, max(ceil($num_items / $per_page), 1));
}

// Server functions (building urls, redirecting...)

/**
* Append session id to url.
* This function supports hooks.
*
* @param string $url The url the session id needs to be appended to (can have params)
* @param mixed $params String or array of additional url parameters
* @param bool $is_amp Is url using &amp; (true) or & (false)
* @param string $session_id Possibility to use a custom session id instead of the global one
*
* Examples:
* <code>
* append_sid(PHPBB_ROOT_PATH . 'viewtopic.' . PHP_EXT . '?t=1&amp;f=2');
* append_sid(PHPBB_ROOT_PATH . 'viewtopic.' . PHP_EXT, 't=1&amp;f=2');
* append_sid('viewtopic', 't=1&amp;f=2'); // short notation of the above example
* append_sid('viewtopic', 't=1&f=2', false);
* append_sid('viewtopic', array('t' => 1, 'f' => 2));
* </code>
*
*/
function append_sid($url, $params = false, $is_amp = true, $session_id = false)
{
        global $_SID, $_EXTRA_URL, $phpbb_hook;
        static $parsed_urls = array();

        // Adjust internal url before calling the hook - we are able to just leave out any path and extension.
        // In this case the root path and extension are added before going through this function.
        if (isset($parsed_urls[$url]))
        {
                $url = $parsed_urls[$url];
        }
        else
        {
                if (strpos($url, '.' . PHP_EXT) === false && $url[0] != '.' && $url[0] != '/')
                {
                        $parsed_urls[$url] = $url = PHPBB_ROOT_PATH . $url . '.' . PHP_EXT;
                }
        }

        if (empty($params))
        {
                $params = false;
        }

        // Developers using the hook function need to globalise the $_SID and $_EXTRA_URL on their own and also handle it appropiatly.
        // They could mimick most of what is within this function
        if (!empty($phpbb_hook) && $phpbb_hook->call_hook(__FUNCTION__, $url, $params, $is_amp, $session_id))
        {
                if ($phpbb_hook->hook_return(__FUNCTION__))
                {
                        return $phpbb_hook->hook_return_result(__FUNCTION__);
                }
        }

        // Assign sid if session id is not specified
        if ($session_id === false)
        {
                $session_id = $_SID;
        }

        $amp_delim = ($is_amp) ? '&amp;' : '&';
        $url_delim = (strpos($url, '?') === false) ? '?' : $amp_delim;

        // Appending custom url parameter?
        $append_url = (!empty($_EXTRA_URL)) ? implode($amp_delim, $_EXTRA_URL) : '';

        $anchor = '';
        if (strpos($url, '#') !== false)
        {
                list($url, $anchor) = explode('#', $url, 2);
                $anchor = '#' . $anchor;
        }
        else if (!is_array($params) && strpos($params, '#') !== false)
        {
                list($params, $anchor) = explode('#', $params, 2);
                $anchor = '#' . $anchor;
        }

        // Use the short variant if possible ;)
        if ($params === false)
        {
                // Append session id
                if (!$session_id)
                {
                        return $url . (($append_url) ? $url_delim . $append_url : '') . $anchor;
                }
                else
                {
                        return $url . (($append_url) ? $url_delim . $append_url . $amp_delim : $url_delim) . 'sid=' . $session_id . $anchor;
                }
        }

        // Build string if parameters are specified as array
        if (is_array($params))
        {
                $output = array();

                foreach ($params as $key => $item)
                {
                        if ($item === NULL)
                        {
                                continue;
                        }

                        if ($key == '#')
                        {
                                $anchor = '#' . $item;
                                continue;
                        }

                        $output[] = $key . '=' . $item;
                }

                $params = implode($amp_delim, $output);
        }

        // Append session id and parameters (even if they are empty)
        // If parameters are empty, the developer can still append his/her parameters without caring about the delimiter
        return $url . (($append_url) ? $url_delim . $append_url . $amp_delim : $url_delim) . $params . ((!$session_id) ? '' : $amp_delim . 'sid=' . $session_id) . $anchor;
}

/**
* Generate board url (example: http://www.example.com/phpBB)
* @param bool $without_script_path if set to true the script path gets not appended (example: http://www.example.com)
*/
function generate_board_url($without_script_path = false)
{
        global $config, $user;

        $server_name = $user->host;
        $server_port = (!empty($_SERVER['SERVER_PORT'])) ? (int) $_SERVER['SERVER_PORT'] : (int) getenv('SERVER_PORT');

        // Forcing server vars is the only way to specify/override the protocol
        if ($config['force_server_vars'] || !$server_name)
        {
                $server_protocol = ($config['server_protocol']) ? $config['server_protocol'] : (($config['cookie_secure']) ? 'https://' : 'http://');
                $server_name = $config['server_name'];
                $server_port = (int) $config['server_port'];
                $script_path = $config['script_path'];

                $url = $server_protocol . $server_name;
        }
        else
        {
                // Do not rely on cookie_secure, users seem to think that it means a secured cookie instead of an encrypted connection
                $cookie_secure = (isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] == 'on') ? 1 : 0;
                $url = (($cookie_secure) ? 'https://' : 'http://') . $server_name;

                $script_path = $user->page['root_script_path'];
        }

        if ($server_port && (($config['cookie_secure'] && $server_port <> 443) || (!$config['cookie_secure'] && $server_port <> 80)))
        {
                // HTTP HOST can carry a port number (we fetch $user->host, but for old versions this may be true)
                if (strpos($server_name, ':') === false)
                {
                        $url .= ':' . $server_port;
                }
        }

        if (!$without_script_path)
        {
                $url .= $script_path;
        }

        // Strip / from the end
        if (substr($url, -1, 1) == '/')
        {
                $url = substr($url, 0, -1);
        }

        return $url;
}

/**
* Redirects the user to another page then exits the script nicely
* This function is intended for urls within the board. It's not meant to redirect to cross-domains.
*/
function redirect($url, $return = false)
{
        global $db, $cache, $config, $user;

        if (empty($user->lang))
        {
                $user->add_lang('common');
        }

        if (!$return)
        {
                garbage_collection();
        }

        // Make sure no &amp;'s are in, this will break the redirect
        $url = str_replace('&amp;', '&', $url);

        // Determine which type of redirect we need to handle...
        $url_parts = parse_url($url);

        if ($url_parts === false)
        {
                // Malformed url, redirect to current page...
                $url = generate_board_url() . '/' . $user->page['page'];
        }
        else if (!empty($url_parts['scheme']) && !empty($url_parts['host']))
        {
                // Attention: only able to redirect within the same domain (yourdomain.com -> www.yourdomain.com will not work)
                if ($url_parts['host'] !== $user->host)
                {
                        $url = generate_board_url();
                }
        }
        else if ($url[0] == '/')
        {
                // Absolute uri, prepend direct url...
                $url = generate_board_url(true) . $url;
        }
        else
        {
                // Relative uri
                $pathinfo = pathinfo($url);

                // Is the uri pointing to the current directory?
                if ($pathinfo['dirname'] == '.')
                {
                        $url = str_replace('./', '', $url);

                        // Strip / from the beginning
                        if ($url && substr($url, 0, 1) == '/')
                        {
                                $url = substr($url, 1);
                        }

                        if ($user->page['page_dir'])
                        {
                                $url = generate_board_url() . '/' . $user->page['page_dir'] . '/' . $url;
                        }
                        else
                        {
                                $url = generate_board_url() . '/' . $url;
                        }
                }
                else
                {
                        // Used ./ before, but PHPBB_ROOT_PATH is working better with urls within another root path
                        $root_dirs = explode('/', str_replace('\\', '/', phpbb_realpath(PHPBB_ROOT_PATH)));
                        $page_dirs = explode('/', str_replace('\\', '/', phpbb_realpath($pathinfo['dirname'])));
                        $intersection = array_intersect_assoc($root_dirs, $page_dirs);

                        $root_dirs = array_diff_assoc($root_dirs, $intersection);
                        $page_dirs = array_diff_assoc($page_dirs, $intersection);

                        $dir = str_repeat('../', sizeof($root_dirs)) . implode('/', $page_dirs);

                        // Strip / from the end
                        if ($dir && substr($dir, -1, 1) == '/')
                        {
                                $dir = substr($dir, 0, -1);
                        }

                        // Strip / from the beginning
                        if ($dir && substr($dir, 0, 1) == '/')
                        {
                                $dir = substr($dir, 1);
                        }

                        $url = str_replace($pathinfo['dirname'] . '/', '', $url);

                        // Strip / from the beginning
                        if (substr($url, 0, 1) == '/')
                        {
                                $url = substr($url, 1);
                        }

                        $url = $dir . '/' . $url;
                        $url = generate_board_url() . '/' . $url;
                }
        }

        // Make sure no linebreaks are there... to prevent http response splitting for PHP < 4.4.2
        if (strpos(urldecode($url), "\n") !== false || strpos(urldecode($url), "\r") !== false || strpos($url, ';') !== false)
        {
                trigger_error('Tried to redirect to potentially insecure url.', E_USER_ERROR);
        }

        // Now, also check the protocol and for a valid url the last time...
        $allowed_protocols = array('http', 'https', 'ftp', 'ftps');
        $url_parts = parse_url($url);

        if ($url_parts === false || empty($url_parts['scheme']) || !in_array($url_parts['scheme'], $allowed_protocols))
        {
                trigger_error('Tried to redirect to potentially insecure url.', E_USER_ERROR);
        }

        if ($return)
        {
                return $url;
        }

        // Redirect via an HTML form for PITA webservers
        if (@preg_match('#Microsoft|WebSTAR|Xitami#', getenv('SERVER_SOFTWARE')))
        {
                header('Refresh: 0; URL=' . $url);

                echo '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">';
                echo '<html xmlns="http://www.w3.org/1999/xhtml" dir="' . $user->lang['DIRECTION'] . '" lang="' . $user->lang['USER_LANG'] . '" xml:lang="' . $user->lang['USER_LANG'] . '">';
                echo '<head>';
                echo '<meta http-equiv="content-type" content="text/html; charset=utf-8" />';
                echo '<meta http-equiv="refresh" content="0; url=' . str_replace('&', '&amp;', $url) . '" />';
                echo '<title>' . $user->lang['REDIRECT'] . '</title>';
                echo '</head>';
                echo '<body>';
                echo '<div style="text-align: center;">' . sprintf($user->lang['URL_REDIRECT'], '<a href="' . str_replace('&', '&amp;', $url) . '">', '</a>') . '</div>';
                echo '</body>';
                echo '</html>';

                exit;
        }

        // Behave as per HTTP/1.1 spec for others
        header('Location: ' . $url);
        exit;
}

/**
* Re-Apply session id after page reloads
*/
function reapply_sid($url)
{
        if ($url === 'index.' . PHP_EXT)
        {
                return append_sid('index.' . PHP_EXT);
        }
        else if ($url === PHPBB_ROOT_PATH . 'index.' . PHP_EXT)
        {
                return append_sid('index');
        }

        // Remove previously added sid
        if (strpos($url, '?sid=') !== false)
        {
                $url = preg_replace('/(\?)sid=[a-z0-9]+(&amp;|&)?/', '\1', $url);
        }
        else if (strpos($url, '&sid=') !== false)
        {
                $url = preg_replace('/&sid=[a-z0-9]+(&)?/', '\1', $url);
        }
        else if (strpos($url, '&amp;sid=') !== false)
        {
                $url = preg_replace('/&amp;sid=[a-z0-9]+(&amp;)?/', '\1', $url);
        }

        return append_sid($url);
}

/**
* Returns url from the session/current page with an re-appended SID with optionally stripping vars from the url
*/
function build_url($strip_vars = false)
{
        global $user;

        // Append SID
        $redirect = append_sid($user->page['page'], false, false);

        // Add delimiter if not there...
        if (strpos($redirect, '?') === false)
        {
                $redirect .= '?';
        }

        // Strip vars...
        if ($strip_vars !== false && strpos($redirect, '?') !== false)
        {
                if (!is_array($strip_vars))
                {
                        $strip_vars = array($strip_vars);
                }

                $query = $_query = array();

                $args = substr($redirect, strpos($redirect, '?') + 1);
                $args = ($args) ? explode('&', $args) : array();
                $redirect = substr($redirect, 0, strpos($redirect, '?'));

                foreach ($args as $argument)
                {
                        $arguments = explode('=', $argument);
                        $key = $arguments[0];
                        unset($arguments[0]);

                        $query[$key] = implode('=', $arguments);
                }

                // Strip the vars off
                foreach ($strip_vars as $strip)
                {
                        if (isset($query[$strip]))
                        {
                                unset($query[$strip]);
                        }
                }

                // Glue the remaining parts together... already urlencoded
                foreach ($query as $key => $value)
                {
                        $_query[] = $key . '=' . $value;
                }
                $query = implode('&', $_query);

                $redirect .= ($query) ? '?' . $query : '';
        }

        return PHPBB_ROOT_PATH . str_replace('&', '&amp;', $redirect);
}

/**
* Meta refresh assignment
*/
function meta_refresh($time, $url)
{
        global $template;

        $url = redirect($url, true);
        $url = str_replace('&', '&amp;', $url);

        // For XHTML compatibility we change back & to &amp;
        $template->assign_vars(array(
                'META' => '<meta http-equiv="refresh" content="' . $time . ';url=' . $url . '" />')
        );

        return $url;
}

//Form validation

/**
* Add a secret token to the form (requires the S_FORM_TOKEN template variable)
* @param string  $form_name The name of the form; has to match the name used in check_form_key, otherwise no restrictions apply
*/
function add_form_key($form_name)
{
        global $config, $template, $user;
        $now = time();
        $token_sid = ($user->data['user_id'] == ANONYMOUS && !empty($config['form_token_sid_guests'])) ? $user->session_id : '';
        $token = sha1($now . $user->data['user_form_salt'] . $form_name . $token_sid);

        $s_fields = build_hidden_fields(array(
                        'creation_time' => $now,
                        'form_token'    => $token,
        ));
        $template->assign_vars(array(
                        'S_FORM_TOKEN'  => $s_fields,
        ));
}

/**
* Check the form key. Required for all altering actions not secured by confirm_box
* @param string  $form_name The name of the form; has to match the name used in add_form_key, otherwise no restrictions apply
* @param int $timespan The maximum acceptable age for a submitted form in seconds. Defaults to the config setting.
* @param string $return_page The address for the return link
* @param bool $trigger If true, the function will triger an error when encountering an invalid form
*/
function check_form_key($form_name, $timespan = false, $return_page = '', $trigger = false)
{
        global $config, $user;

        if ($timespan === false)
        {
                // we enforce a minimum value of half a minute here.
                $timespan = ($config['form_token_lifetime'] == -1) ? -1 : max(30, $config['form_token_lifetime']);
        }

        if (isset($_POST['creation_time']) && isset($_POST['form_token']))
        {
                $creation_time  = abs(request_var('creation_time', 0));
                $token = request_var('form_token', '');

                $diff = (time() - $creation_time);

                if (($diff <= $timespan) || $timespan === -1)
                {
                        $token_sid = ($user->data['user_id'] == ANONYMOUS && !empty($config['form_token_sid_guests'])) ? $user->session_id : '';

                        $key = sha1($creation_time . $user->data['user_form_salt'] . $form_name . $token_sid);
                        if ($key === $token)
                        {
                                return true;
                        }
                }
        }
        if ($trigger)
        {
                trigger_error($user->lang['FORM_INVALID'] . $return_page);
        }
        return false;
}

// Message/Login boxes

/**
* Build Confirm box
* @param boolean $check True for checking if confirmed (without any additional parameters) and false for displaying the confirm box
* @param string $title Title/Message used for confirm box.
*               message text is _CONFIRM appended to title.
*               If title cannot be found in user->lang a default one is displayed
*               If title_CONFIRM cannot be found in user->lang the text given is used.
* @param string $hidden Hidden variables
* @param string $html_body Template used for confirm box
* @param string $u_action Custom form action
*/
function confirm_box($check, $title = '', $hidden = '', $html_body = 'confirm_body.html', $u_action = '')
{
        global $user, $template, $db;

        if (isset($_POST['cancel']))
        {
                return false;
        }

        $confirm = false;
        if (isset($_POST['confirm']))
        {
                // language frontier
                if ($_POST['confirm'] === $user->lang['YES'])
                {
                        $confirm = true;
                }
        }

        if ($check && $confirm)
        {
                $user_id = request_var('user_id', 0);
                $session_id = request_var('sess', '');
                $confirm_key = request_var('confirm_key', '');

                if ($user_id != $user->data['user_id'] || $session_id != $user->session_id || !$confirm_key || !$user->data['user_last_confirm_key'] || $confirm_key != $user->data['user_last_confirm_key'])
                {
                        return false;
                }

                // Reset user_last_confirm_key
                $sql = 'UPDATE ' . USERS_TABLE . " SET user_last_confirm_key = ''
                        WHERE user_id = " . $user->data['user_id'];
                $db->sql_query($sql);

                return true;
        }
        else if ($check)
        {
                return false;
        }

        $s_hidden_fields = build_hidden_fields(array(
                'user_id'       => $user->data['user_id'],
                'sess'          => $user->session_id,
                'sid'           => $user->session_id)
        );

        // generate activation key
        $confirm_key = gen_rand_string(10);

        if (defined('IN_ADMIN') && isset($user->data['session_admin']) && $user->data['session_admin'])
        {
                adm_page_header((!isset($user->lang[$title])) ? $user->lang['CONFIRM'] : $user->lang[$title]);
        }
        else
        {
                page_header((!isset($user->lang[$title])) ? $user->lang['CONFIRM'] : $user->lang[$title]);
        }

        $template->set_filenames(array(
                'body' => $html_body)
        );

        // If activation key already exist, we better do not re-use the key (something very strange is going on...)
        if (request_var('confirm_key', ''))
        {
                // This should not occur, therefore we cancel the operation to safe the user
                return false;
        }

        // re-add sid / transform & to &amp; for user->page (user->page is always using &)
        $use_page = ($u_action) ? PHPBB_ROOT_PATH . $u_action : PHPBB_ROOT_PATH . str_replace('&', '&amp;', $user->page['page']);
        $u_action = reapply_sid($use_page);
        $u_action .= ((strpos($u_action, '?') === false) ? '?' : '&amp;') . 'confirm_key=' . $confirm_key;

        $template->assign_vars(array(
                'MESSAGE_TITLE'         => (!isset($user->lang[$title])) ? $user->lang['CONFIRM'] : $user->lang[$title],
                'MESSAGE_TEXT'          => (!isset($user->lang[$title . '_CONFIRM'])) ? $title : $user->lang[$title . '_CONFIRM'],

                'YES_VALUE'                     => $user->lang['YES'],
                'S_CONFIRM_ACTION'      => $u_action,
                'S_HIDDEN_FIELDS'       => $hidden . $s_hidden_fields)
        );

        $sql = 'UPDATE ' . USERS_TABLE . " SET user_last_confirm_key = '" . $db->sql_escape($confirm_key) . "'
                WHERE user_id = " . $user->data['user_id'];
        $db->sql_query($sql);

        if (defined('IN_ADMIN') && isset($user->data['session_admin']) && $user->data['session_admin'])
        {
                adm_page_footer();
        }
        else
        {
                page_footer();
        }
}

/**
* Generate login box or verify password
*/
function login_box($redirect = '', $l_explain = '', $l_success = '', $admin = false, $s_display = true)
{
        global $db, $user, $template, $auth, $config;


        $err = '';

        // Make sure user->setup() has been called
        if (empty($user->lang))
        {
                $user->setup();
        }

        if (defined('ADMIN_START'))
        {
                // Set custom template for admin area
                $template->set_custom_template(PHPBB_ADMIN_PATH . 'style', 'admin');
                $template->assign_var('T_TEMPLATE_PATH', PHPBB_ADMIN_PATH . 'style');

                // the acp template is never stored in the database
                $user->theme['template_storedb'] = false;
        }

        // Print out error if user tries to authenticate as an administrator without having the privileges...
        if ($admin && !$auth->acl_get('a_'))
        {
                // Not authd
                // anonymous/inactive users are never able to go to the ACP even if they have the relevant permissions
                if ($user->data['is_registered'])
                {
                        add_log('admin', 'LOG_ADMIN_AUTH_FAIL');
                }
                trigger_error('NO_AUTH_ADMIN');
        }

        if (isset($_POST['login']))
        {
                // Get credential
                if ($admin)
                {
                        $credential = request_var('credential', '');

                        if (strspn($credential, 'abcdef0123456789') !== strlen($credential) || strlen($credential) != 32)
                        {
                                if ($user->data['is_registered'])
                                {
                                        add_log('admin', 'LOG_ADMIN_AUTH_FAIL');
                                }
                                trigger_error('NO_AUTH_ADMIN');
                        }

                        $password       = request_var('password_' . $credential, '', true);
                }
                else
                {
                        $password       = request_var('password', '', true);
                }

                $username       = request_var('username', '', true);
                $autologin      = (!empty($_POST['autologin'])) ? true : false;
                $viewonline = (!empty($_POST['viewonline'])) ? 0 : 1;
                $admin          = ($admin) ? 1 : 0;
                $viewonline = ($admin) ? $user->data['session_viewonline'] : $viewonline;

                // Check if the supplied username is equal to the one stored within the database if re-authenticating
                if ($admin && utf8_clean_string($username) != utf8_clean_string($user->data['username']))
                {
                        // We log the attempt to use a different username...
                        add_log('admin', 'LOG_ADMIN_AUTH_FAIL');
                        trigger_error('NO_AUTH_ADMIN_USER_DIFFER');
                }

                // If authentication is successful we redirect user to previous page
                $result = $auth->login($username, $password, $autologin, $viewonline, $admin);

                // If admin authentication and login, we will log if it was a success or not...
                // We also break the operation on the first non-success login - it could be argued that the user already knows
                if ($admin)
                {
                        if ($result['status'] == LOGIN_SUCCESS)
                        {
                                add_log('admin', 'LOG_ADMIN_AUTH_SUCCESS');
                        }
                        else
                        {
                                // Only log the failed attempt if a real user tried to.
                                // anonymous/inactive users are never able to go to the ACP even if they have the relevant permissions
                                if ($user->data['is_registered'])
                                {
                                        add_log('admin', 'LOG_ADMIN_AUTH_FAIL');
                                }
                        }
                }

                // The result parameter is always an array, holding the relevant information...
                if ($result['status'] == LOGIN_SUCCESS)
                {
                        $redirect = request_var('redirect', PHPBB_ROOT_PATH . 'index.' . PHP_EXT);
                        $message = ($l_success) ? $l_success : $user->lang['LOGIN_REDIRECT'];
                        $l_redirect = ($admin) ? $user->lang['PROCEED_TO_ACP'] : (($redirect === PHPBB_ROOT_PATH . 'index.' . PHP_EXT || $redirect === "index." . PHP_EXT) ? $user->lang['RETURN_INDEX'] : $user->lang['RETURN_PAGE']);

                        // append/replace SID (may change during the session for AOL users)
                        $redirect = reapply_sid($redirect);

                        // Special case... the user is effectively banned, but we allow founders to login
                        if (defined('IN_CHECK_BAN') && $result['user_row']['user_type'] != USER_FOUNDER)
                        {
                                return;
                        }

                        $redirect = meta_refresh(3, $redirect);
                        trigger_error($message . '<br /><br />' . sprintf($l_redirect, '<a href="' . $redirect . '">', '</a>'));
                }

                // Something failed, determine what...
                if ($result['status'] == LOGIN_BREAK)
                {
                        trigger_error($result['error_msg']);
                }

                // Special cases... determine
                switch ($result['status'])
                {
                        case LOGIN_ERROR_ATTEMPTS:

                                // Show confirm image
                                $sql = 'DELETE FROM ' . CONFIRM_TABLE . "
                                        WHERE session_id = '" . $db->sql_escape($user->session_id) . "'
                                                AND confirm_type = " . CONFIRM_LOGIN;
                                $db->sql_query($sql);

                                // Generate code
                                $code = gen_rand_string(mt_rand(5, 8));
                                $confirm_id = md5(unique_id($user->ip));
                                $seed = hexdec(substr(unique_id(), 4, 10));

                                // compute $seed % 0x7fffffff
                                $seed -= 0x7fffffff * floor($seed / 0x7fffffff);

                                $sql = 'INSERT INTO ' . CONFIRM_TABLE . ' ' . $db->sql_build_array('INSERT', array(
                                        'confirm_id'    => (string) $confirm_id,
                                        'session_id'    => (string) $user->session_id,
                                        'confirm_type'  => (int) CONFIRM_LOGIN,
                                        'code'                  => (string) $code,
                                        'seed'                  => (int) $seed)
                                );
                                $db->sql_query($sql);

                                $template->assign_vars(array(
                                        'S_CONFIRM_CODE'                        => true,
                                        'CONFIRM_ID'                            => $confirm_id,
                                        'CONFIRM_IMAGE'                         => '<img src="' . append_sid('ucp', 'mode=confirm&amp;id=' . $confirm_id . '&amp;type=' . CONFIRM_LOGIN) . '" alt="" title="" />',
                                        'L_LOGIN_CONFIRM_EXPLAIN'       => sprintf($user->lang['LOGIN_CONFIRM_EXPLAIN'], '<a href="mailto:' . htmlspecialchars($config['board_contact']) . '">', '</a>'),
                                ));

                                $err = $user->lang[$result['error_msg']];

                        break;

                        case LOGIN_ERROR_PASSWORD_CONVERT:
                                $err = sprintf(
                                        $user->lang[$result['error_msg']],
                                        ($config['email_enable']) ? '<a href="' . append_sid('ucp', 'mode=sendpassword') . '">' : '',
                                        ($config['email_enable']) ? '</a>' : '',
                                        ($config['board_contact']) ? '<a href="mailto:' . htmlspecialchars($config['board_contact']) . '">' : '',
                                        ($config['board_contact']) ? '</a>' : ''
                                );
                        break;

                        // Username, password, etc...
                        default:
                                $err = $user->lang[$result['error_msg']];

                                // Assign admin contact to some error messages
                                if ($result['error_msg'] == 'LOGIN_ERROR_USERNAME' || $result['error_msg'] == 'LOGIN_ERROR_PASSWORD')
                                {
                                        $err = (!$config['board_contact']) ? sprintf($user->lang[$result['error_msg']], '', '') : sprintf($user->lang[$result['error_msg']], '<a href="mailto:' . htmlspecialchars($config['board_contact']) . '">', '</a>');
                                }

                        break;
                }
        }

        if (!$redirect)
        {
                // We just use what the session code determined...
                // If we are not within the admin directory we use the page dir...
                $redirect = '';

                if (!$admin && !defined('ADMIN_START'))
                {
                        $redirect .= ($user->page['page_dir']) ? $user->page['page_dir'] . '/' : '';
                }

                $redirect .= $user->page['page_name'] . (($user->page['query_string']) ? '?' . htmlspecialchars($user->page['query_string']) : '');
        }

        // Assign credential for username/password pair
        $credential = ($admin) ? md5(unique_id()) : false;

        $s_hidden_fields = array(
                'redirect'      => $redirect,
                'sid'           => $user->session_id,
        );

        if ($admin)
        {
                $s_hidden_fields['credential'] = $credential;
        }

        $s_hidden_fields = build_hidden_fields($s_hidden_fields);

        $template->assign_vars(array(
                'LOGIN_ERROR'           => $err,
                'LOGIN_EXPLAIN'         => $l_explain,

                'U_SEND_PASSWORD'               => ($config['email_enable']) ? append_sid('ucp', 'mode=sendpassword') : '',
                'U_RESEND_ACTIVATION'   => ($config['require_activation'] != USER_ACTIVATION_NONE && $config['email_enable']) ? append_sid('ucp', 'mode=resend_act') : '',
                'U_TERMS_USE'                   => append_sid('ucp', 'mode=terms'),
                'U_PRIVACY'                             => append_sid('ucp', 'mode=privacy'),

                'S_DISPLAY_FULL_LOGIN'  => ($s_display) ? true : false,
                'S_LOGIN_ACTION'                => (!$admin && !defined('ADMIN_START'))  ? append_sid('ucp', 'mode=login') : append_sid(PHPBB_ADMIN_PATH . 'index.' . PHP_EXT, false, true, $user->session_id),
                'S_HIDDEN_FIELDS'               => $s_hidden_fields,

                'S_ADMIN_AUTH'                  => $admin,
                'S_ACP_LOGIN'                   => defined('ADMIN_START'),
                'USERNAME'                              => ($admin) ? $user->data['username'] : '',

                'USERNAME_CREDENTIAL'   => 'username',
                'PASSWORD_CREDENTIAL'   => ($admin) ? 'password_' . $credential : 'password',
        ));

        if (defined('ADMIN_START'))
        {
                $template->set_filenames(array(
                        'body' => 'acp_login.html')
                );
                $template->assign_block_vars('t_block1', array(
                        'L_TITLE'               => $user->lang['LOGIN'],
                        'S_SELECTED'    => true,
                        'U_TITLE'               => '',
                ));
                adm_page_header($user->lang['LOGIN'], false);
        }
        else
        {
                $template->set_filenames(array(
                        'body' => 'login_body.html')
                );
                page_header($user->lang['LOGIN'], false);
        }

        make_jumpbox(append_sid('viewforum'));
        if (defined('ADMIN_START') && isset($user->data['session_admin']) && $user->data['session_admin'])
        {
                adm_page_footer();
        }
        else
        {
                page_footer();
        }

}

/**
* Generate forum login box
*/
function login_forum_box($forum_data)
{
        global $db, $config, $user, $template;

        $password = request_var('password', '', true);

        $sql = 'SELECT forum_id
                FROM ' . FORUMS_ACCESS_TABLE . '
                WHERE forum_id = ' . $forum_data['forum_id'] . '
                        AND user_id = ' . $user->data['user_id'] . "
                        AND session_id = '" . $db->sql_escape($user->session_id) . "'";
        $result = $db->sql_query($sql);
        $row = $db->sql_fetchrow($result);
        $db->sql_freeresult($result);

        if ($row)
        {
                return true;
        }

        if ($password)
        {
                // Remove expired authorised sessions
                $sql = 'SELECT f.session_id
                        FROM ' . FORUMS_ACCESS_TABLE . ' f
                        LEFT JOIN ' . SESSIONS_TABLE . ' s ON (f.session_id = s.session_id)
                        WHERE s.session_id IS NULL';
                $result = $db->sql_query($sql);

                if ($row = $db->sql_fetchrow($result))
                {
                        $sql_in = array();
                        do
                        {
                                $sql_in[] = (string) $row['session_id'];
                        }
                        while ($row = $db->sql_fetchrow($result));

                        // Remove expired sessions
                        $sql = 'DELETE FROM ' . FORUMS_ACCESS_TABLE . '
                                WHERE ' . $db->sql_in_set('session_id', $sql_in);
                        $db->sql_query($sql);
                }
                $db->sql_freeresult($result);

                if (phpbb_check_hash($password, $forum_data['forum_password']))
                {
                        $sql_ary = array(
                                'forum_id'              => (int) $forum_data['forum_id'],
                                'user_id'               => (int) $user->data['user_id'],
                                'session_id'    => (string) $user->session_id,
                        );

                        $db->sql_query('INSERT INTO ' . FORUMS_ACCESS_TABLE . ' ' . $db->sql_build_array('INSERT', $sql_ary));

                        return true;
                }

                $template->assign_var('LOGIN_ERROR', $user->lang['WRONG_PASSWORD']);
        }

        page_header($user->lang['LOGIN']);

        $template->assign_vars(array(
                'S_HIDDEN_FIELDS'               => build_hidden_fields(array('f' => $forum_data['forum_id'])))
        );

        $template->set_filenames(array(
                'body' => 'login_forum.html')
        );

        page_footer();
}

// Little helpers

/**
* Little helper for the build_hidden_fields function
*/
function _build_hidden_fields($key, $value, $specialchar, $stripslashes)
{
        $hidden_fields = '';

        if (!is_array($value))
        {
                $value = ($stripslashes) ? stripslashes($value) : $value;
                $value = ($specialchar) ? htmlspecialchars($value, ENT_COMPAT, 'UTF-8') : $value;

                $hidden_fields .= '<input type="hidden" name="' . $key . '" value="' . $value . '" />' . "\n";
        }
        else
        {
                foreach ($value as $_key => $_value)
                {
                        $_key = ($stripslashes) ? stripslashes($_key) : $_key;
                        $_key = ($specialchar) ? htmlspecialchars($_key, ENT_COMPAT, 'UTF-8') : $_key;

                        $hidden_fields .= _build_hidden_fields($key . '[' . $_key . ']', $_value, $specialchar, $stripslashes);
                }
        }

        return $hidden_fields;
}

/**
* Build simple hidden fields from array
*
* @param array $field_ary an array of values to build the hidden field from
* @param bool $specialchar if true, keys and values get specialchared
* @param bool $stripslashes if true, keys and values get stripslashed
*
* @return string the hidden fields
*/
function build_hidden_fields($field_ary, $specialchar = false, $stripslashes = false)
{
        $s_hidden_fields = '';

        foreach ($field_ary as $name => $vars)
        {
                $name = ($stripslashes) ? stripslashes($name) : $name;
                $name = ($specialchar) ? htmlspecialchars($name, ENT_COMPAT, 'UTF-8') : $name;

                $s_hidden_fields .= _build_hidden_fields($name, $vars, $specialchar, $stripslashes);
        }

        return $s_hidden_fields;
}

/**
* Parse cfg file
*/
function parse_cfg_file($filename, $lines = false)
{
        $parsed_items = array();

        if ($lines === false)
        {
                $lines = file($filename);
        }

        foreach ($lines as $line)
        {
                $line = trim($line);

                if (!$line || $line[0] == '#' || ($delim_pos = strpos($line, '=')) === false)
                {
                        continue;
                }

                // Determine first occurrence, since in values the equal sign is allowed
                $key = strtolower(trim(substr($line, 0, $delim_pos)));
                $value = trim(substr($line, $delim_pos + 1));

                if (in_array($value, array('off', 'false', '0')))
                {
                        $value = false;
                }
                else if (in_array($value, array('on', 'true', '1')))
                {
                        $value = true;
                }
                else if (!trim($value))
                {
                        $value = '';
                }
                else if (($value[0] == "'" && $value[sizeof($value) - 1] == "'") || ($value[0] == '"' && $value[sizeof($value) - 1] == '"'))
                {
                        $value = substr($value, 1, sizeof($value)-2);
                }

                $parsed_items[$key] = $value;
        }

        return $parsed_items;
}

/**
* Add log event
*/
function add_log()
{
        global $db, $user;

        $args = func_get_args();

        $mode                   = array_shift($args);
        $reportee_id    = ($mode == 'user') ? intval(array_shift($args)) : '';
        $forum_id               = ($mode == 'mod') ? intval(array_shift($args)) : '';
        $topic_id               = ($mode == 'mod') ? intval(array_shift($args)) : '';
        $action                 = array_shift($args);
        $data                   = (!sizeof($args)) ? '' : serialize($args);

        $sql_ary = array(
                'user_id'               => (empty($user->data)) ? ANONYMOUS : $user->data['user_id'],
                'log_ip'                => $user->ip,
                'log_time'              => time(),
                'log_operation' => $action,
                'log_data'              => $data,
        );

        switch ($mode)
        {
                case 'admin':
                        $sql_ary['log_type'] = LOG_ADMIN;
                break;

                case 'mod':
                        $sql_ary += array(
                                'log_type'      => LOG_MOD,
                                'forum_id'      => $forum_id,
                                'topic_id'      => $topic_id
                        );
                break;

                case 'user':
                        $sql_ary += array(
                                'log_type'              => LOG_USERS,
                                'reportee_id'   => $reportee_id
                        );
                break;

                case 'critical':
                        $sql_ary['log_type'] = LOG_CRITICAL;
                break;

                default:
                        return false;
        }

        $db->sql_query('INSERT INTO ' . LOG_TABLE . ' ' . $db->sql_build_array('INSERT', $sql_ary));

        return $db->sql_nextid();
}

/**
* Return a nicely formatted backtrace (parts from the php manual by diz at ysagoon dot com)
*/
function get_backtrace()
{
        $output = '<div style="font-family: monospace;">';
        $backtrace = debug_backtrace();
        $path = phpbb_realpath(PHPBB_ROOT_PATH);

        foreach ($backtrace as $number => $trace)
        {
                // We skip the first one, because it only shows this file/function
                if ($number == 0)
                {
                        continue;
                }

                // Strip the current directory from path
                if (empty($trace['file']))
                {
                        $trace['file'] = '';
                }
                else
                {
                        $trace['file'] = str_replace(array($path, '\\'), array('', '/'), $trace['file']);
                        $trace['file'] = substr($trace['file'], 1);
                }
                $args = array();

                // If include/require/include_once is not called, do not show arguments - they may contain sensible information
                if (!in_array($trace['function'], array('include', 'require', 'include_once')))
                {
                        unset($trace['args']);
                }
                else
                {
                        // Path...
                        if (!empty($trace['args'][0]))
                        {
                                $argument = htmlspecialchars($trace['args'][0]);
                                $argument = str_replace(array($path, '\\'), array('', '/'), $argument);
                                $argument = substr($argument, 1);
                                $args[] = "'{$argument}'";
                        }
                }

                $trace['class'] = (!isset($trace['class'])) ? '' : $trace['class'];
                $trace['type'] = (!isset($trace['type'])) ? '' : $trace['type'];

                $output .= '<br />';
                $output .= '<b>FILE:</b> ' . htmlspecialchars($trace['file']) . '<br />';
                $output .= '<b>LINE:</b> ' . ((!empty($trace['line'])) ? $trace['line'] : '') . '<br />';

                $output .= '<b>CALL:</b> ' . htmlspecialchars($trace['class'] . $trace['type'] . $trace['function']) . '(' . ((sizeof($args)) ? implode(', ', $args) : '') . ')<br />';
        }
        $output .= '</div>';
        return $output;
}

/**
* This function returns a regular expression pattern for commonly used expressions
* Use with / as delimiter for email mode and # for url modes
* mode can be: email|bbcode_htm|url|url_inline|www_url|www_url_inline|relative_url|relative_url_inline|ipv4|ipv6
*/
function get_preg_expression($mode)
{
        switch ($mode)
        {
                case 'email':
                        return '(?:[a-z0-9\'\.\-_\+\|]++|&amp;)+@[a-z0-9\-]+\.(?:[a-z0-9\-]+\.)*[a-z]+';
                break;

                case 'bbcode_htm':
                        return array(
                                '#<!\-\- e \-\-><a href="mailto:(.*?)">.*?</a><!\-\- e \-\->#',
                                '#<!\-\- l \-\-><a (?:class="[\w-]+" )?href="(.*?)(?:(&amp;|\?)sid=[0-9a-f]{32})?">.*?</a><!\-\- l \-\->#',
                                '#<!\-\- ([mw]) \-\-><a (?:class="[\w-]+" )?href="(.*?)">.*?</a><!\-\- \1 \-\->#',
                                '#<!\-\- s(.*?) \-\-><img src="\{SMILIES_PATH\}\/.*? \/><!\-\- s\1 \-\->#',
                                '#<!\-\- .*? \-\->#s',
                                '#<.*?>#s',
                        );
                break;

                // Whoa these look impressive!
                // The code to generate the following two regular expressions which match valid IPv4/IPv6 addresses
                // can be found in the develop directory
                case 'ipv4':
                        return '#^(?:(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.){3}(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])$#';
                break;

                case 'ipv6':
                        return '#^(?:(?:(?:[\dA-F]{1,4}:){6}(?:[\dA-F]{1,4}:[\dA-F]{1,4}|(?:(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.){3}(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])))|(?:::(?:[\dA-F]{1,4}:){5}(?:[\dA-F]{1,4}:[\dA-F]{1,4}|(?:(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.){3}(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])))|(?:(?:[\dA-F]{1,4}:):(?:[\dA-F]{1,4}:){4}(?:[\dA-F]{1,4}:[\dA-F]{1,4}|(?:(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.){3}(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])))|(?:(?:[\dA-F]{1,4}:){1,2}:(?:[\dA-F]{1,4}:){3}(?:[\dA-F]{1,4}:[\dA-F]{1,4}|(?:(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.){3}(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])))|(?:(?:[\dA-F]{1,4}:){1,3}:(?:[\dA-F]{1,4}:){2}(?:[\dA-F]{1,4}:[\dA-F]{1,4}|(?:(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.){3}(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])))|(?:(?:[\dA-F]{1,4}:){1,4}:(?:[\dA-F]{1,4}:)(?:[\dA-F]{1,4}:[\dA-F]{1,4}|(?:(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.){3}(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])))|(?:(?:[\dA-F]{1,4}:){1,5}:(?:[\dA-F]{1,4}:[\dA-F]{1,4}|(?:(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.){3}(?:\d{1,2}|1\d\d|2[0-4]\d|25[0-5])))|(?:(?:[\dA-F]{1,4}:){1,6}:[\dA-F]{1,4})|(?:(?:[\dA-F]{1,4}:){1,7}:))$#i';
                break;

                case 'url':
                case 'url_inline':
                        $inline = ($mode == 'url') ? ')' : '';
                        $scheme = ($mode == 'url') ? '[a-z\d+\-.]' : '[a-z\d+]'; // avoid automatic parsing of "word" in "last word.http://..."
                        // generated with regex generation file in the develop folder
                        return "[a-z]$scheme*:/{2}(?:(?:[a-z0-9\-._~!$&'($inline*+,;=:@|]+|%[\dA-F]{2})+|[0-9.]+|\[[a-z0-9.]+:[a-z0-9.]+:[a-z0-9.:]+\])(?::\d*)?(?:/(?:[a-z0-9\-._~!$&'($inline*+,;=:@|]+|%[\dA-F]{2})*)*(?:\?(?:[a-z0-9\-._~!$&'($inline*+,;=:@/?|]+|%[\dA-F]{2})*)?(?:\#(?:[a-z0-9\-._~!$&'($inline*+,;=:@/?|]+|%[\dA-F]{2})*)?";
                break;

                case 'www_url':
                case 'www_url_inline':
                        $inline = ($mode == 'www_url') ? ')' : '';
                        return "www\.(?:[a-z0-9\-._~!$&'($inline*+,;=:@|]+|%[\dA-F]{2})+(?::\d*)?(?:/(?:[a-z0-9\-._~!$&'($inline*+,;=:@|]+|%[\dA-F]{2})*)*(?:\?(?:[a-z0-9\-._~!$&'($inline*+,;=:@/?|]+|%[\dA-F]{2})*)?(?:\#(?:[a-z0-9\-._~!$&'($inline*+,;=:@/?|]+|%[\dA-F]{2})*)?";
                break;

                case 'relative_url':
                case 'relative_url_inline':
                        $inline = ($mode == 'relative_url') ? ')' : '';
                        return "(?:[a-z0-9\-._~!$&'($inline*+,;=:@|]+|%[\dA-F]{2})*(?:/(?:[a-z0-9\-._~!$&'($inline*+,;=:@|]+|%[\dA-F]{2})*)*(?:\?(?:[a-z0-9\-._~!$&'($inline*+,;=:@/?|]+|%[\dA-F]{2})*)?(?:\#(?:[a-z0-9\-._~!$&'($inline*+,;=:@/?|]+|%[\dA-F]{2})*)?";
                break;
        }

        return '';
}

/**
* Returns the first block of the specified IPv6 address and as many additional
* ones as specified in the length paramater.
* If length is zero, then an empty string is returned.
* If length is greater than 3 the complete IP will be returned
*/
function short_ipv6($ip, $length)
{
        if ($length < 1)
        {
                return '';
        }

        // extend IPv6 addresses
        $blocks = substr_count($ip, ':') + 1;
        if ($blocks < 9)
        {
                $ip = str_replace('::', ':' . str_repeat('0000:', 9 - $blocks), $ip);
        }
        if ($ip[0] == ':')
        {
                $ip = '0000' . $ip;
        }
        if ($length < 4)
        {
                $ip = implode(':', array_slice(explode(':', $ip), 0, 1 + $length));
        }

        return $ip;
}

/**
* Wrapper for php's checkdnsrr function.
*
* The windows failover is from the php manual
* Please make sure to check the return value for === true and === false, since NULL could
* be returned too.
*
* @return true if entry found, false if not, NULL if this function is not supported by this environment
*/
function phpbb_checkdnsrr($host, $type = '')
{
        $type = (!$type) ? 'MX' : $type;

        if (DIRECTORY_SEPARATOR == '\\')
        {
                if (!function_exists('exec'))
                {
                        return NULL;
                }

                // @exec('nslookup -retry=1 -timout=1 -type=' . escapeshellarg($type) . ' ' . escapeshellarg($host), $output);
                @exec('nslookup -type=' . escapeshellarg($type) . ' ' . escapeshellarg($host), $output);

                // If output is empty, the nslookup failed
                if (empty($output))
                {
                        return NULL;
                }

                foreach ($output as $line)
                {
                        if (!trim($line))
                        {
                                continue;
                        }

                        // Valid records begin with host name:
                        if (strpos($line, $host) === 0)
                        {
                                return true;
                        }
                }

                return false;
        }
        else if (function_exists('checkdnsrr'))
        {
                return (checkdnsrr($host, $type)) ? true : false;
        }

        return NULL;
}

// Handler, header and footer

/**
* Error and message handler, call with trigger_error if reqd
*/
function msg_handler($errno, $msg_text, $errfile, $errline)
{
        global $cache, $db, $auth, $template, $config, $user;
        global $msg_title, $msg_long_text;

        // Do not display notices if we suppress them via @
        if (error_reporting() == 0)
        {
                return;
        }

        // Message handler is stripping text. In case we need it, we are possible to define long text...
        if (isset($msg_long_text) && $msg_long_text && !$msg_text)
        {
                $msg_text = $msg_long_text;
        }

        switch ($errno)
        {
                case E_NOTICE:
                case E_WARNING:
                case E_STRICT:

                        // Check the error reporting level and return if the error level does not match
                        // If DEBUG is defined the default level is E_ALL
                        if (($errno & ((defined('DEBUG')) ? E_ALL | E_STRICT : error_reporting())) == 0)
                        {
                                return;
                        }

                        if (strpos($errfile, 'cache') === false && strpos($errfile, 'template.') === false)
                        {
                                // flush the content, else we get a white page if output buffering is on
                                if ((int) @ini_get('output_buffering') === 1 || strtolower(@ini_get('output_buffering')) === 'on')
                                {
                                        @ob_flush();
                                }

                                // Another quick fix for those having gzip compression enabled, but do not flush if the coder wants to catch "something". ;)
                                if ($config['gzip_compress'])
                                {
                                        if (@extension_loaded('zlib') && !headers_sent() && !ob_get_level())
                                        {
                                                @ob_flush();
                                        }
                                }

                                // remove complete path to installation, with the risk of changing backslashes meant to be there
                                $errfile = str_replace(array(phpbb_realpath(PHPBB_ROOT_PATH), '\\'), array('', '/'), $errfile);
                                $msg_text = str_replace(array(phpbb_realpath(PHPBB_ROOT_PATH), '\\'), array('', '/'), $msg_text);

                                echo '<b>[phpBB Debug] PHP Notice</b>: in file <b>' . $errfile . '</b> on line <b>' . $errline . '</b>: <b>' . $msg_text . '</b><br />' . "\n";
                        }

                        return;

                break;

                case E_RECOVERABLE_ERROR:
                case E_USER_ERROR:

                        if (!empty($user) && !empty($user->lang))
                        {
                                $msg_text = (!empty($user->lang[$msg_text])) ? $user->lang[$msg_text] : $msg_text;
                                $msg_title = (!isset($msg_title)) ? $user->lang['GENERAL_ERROR'] : ((!empty($user->lang[$msg_title])) ? $user->lang[$msg_title] : $msg_title);

                                $l_return_index = sprintf($user->lang['RETURN_INDEX'], '<a href="' . PHPBB_ROOT_PATH . '">', '</a>');
                                $l_notify = '';

                                if (!empty($config['board_contact']))
                                {
                                        $l_notify = '<p>' . sprintf($user->lang['NOTIFY_ADMIN_EMAIL'], $config['board_contact']) . '</p>';
                                }
                        }
                        else
                        {
                                $msg_title = 'General Error';
                                $l_return_index = '<a href="' . PHPBB_ROOT_PATH . '">Return to index page</a>';
                                $l_notify = '';

                                if (!empty($config['board_contact']))
                                {
                                        $l_notify = '<p>Please notify the board administrator or webmaster: <a href="mailto:' . $config['board_contact'] . '">' . $config['board_contact'] . '</a></p>';
                                }
                        }

                        garbage_collection();

                        // Try to not call the adm page data...

                        echo '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">';
                        echo '<html xmlns="http://www.w3.org/1999/xhtml" dir="ltr">';
                        echo '<head>';
                        echo '<meta http-equiv="content-type" content="text/html; charset=utf-8" />';
                        echo '<title>' . $msg_title . '</title>';
                        echo '<style type="text/css">' . "\n" . '/* <![CDATA[ */' . "\n";
                        echo '* { margin: 0; padding: 0; } html { font-size: 100%; height: 100%; margin-bottom: 1px; background-color: #E4EDF0; } body { font-family: "Lucida Grande", Verdana, Helvetica, Arial, sans-serif; color: #536482; background: #E4EDF0; font-size: 62.5%; margin: 0; } ';
                        echo 'a:link, a:active, a:visited { color: #006699; text-decoration: none; } a:hover { color: #DD6900; text-decoration: underline; } ';
                        echo '#wrap { padding: 0 20px 15px 20px; min-width: 615px; } #page-header { text-align: right; height: 40px; } #page-footer { clear: both; font-size: 1em; text-align: center; } ';
                        echo '.panel { margin: 4px 0; background-color: #FFFFFF; border: solid 1px  #A9B8C2; } ';
                        echo '#errorpage #page-header a { font-weight: bold; line-height: 6em; } #errorpage #content { padding: 10px; } #errorpage #content h1 { line-height: 1.2em; margin-bottom: 0; color: #DF075C; } ';
                        echo '#errorpage #content div { margin-top: 20px; margin-bottom: 5px; border-bottom: 1px solid #CCCCCC; padding-bottom: 5px; color: #333333; font: bold 1.2em "Lucida Grande", Arial, Helvetica, sans-serif; text-decoration: none; line-height: 120%; text-align: left; } ';
                        echo "\n" . '/* ]]> */' . "\n";
                        echo '</style>';
                        echo '</head>';
                        echo '<body id="errorpage">';
                        echo '<div id="wrap">';
                        echo '  <div id="page-header">';
                        echo '          ' . $l_return_index;
                        echo '  </div>';
                        echo '  <div id="acp">';
                        echo '  <div class="panel">';
                        echo '          <div id="content">';
                        echo '                  <h1>' . $msg_title . '</h1>';

                        echo '                  <div>' . $msg_text . '</div>';

                        echo $l_notify;

                        echo '          </div>';
                        echo '  </div>';
                        echo '  </div>';
                        echo '  <div id="page-footer">';
                        echo '          Powered by phpBB &copy; 2000, 2002, 2005, 2007 <a href="http://www.phpbb.com/">phpBB Group</a>';
                        echo '  </div>';
                        echo '</div>';
                        echo '</body>';
                        echo '</html>';

                        exit_handler();
                break;

                case E_USER_WARNING:
                case E_USER_NOTICE:

                        define('IN_ERROR_HANDLER', true);

                        if (empty($user->data))
                        {
                                $user->session_begin();
                        }

                        // We re-init the auth array to get correct results on login/logout
                        $auth->acl($user->data);

                        if (empty($user->lang))
                        {
                                $user->setup();
                        }

                        $msg_text = (!empty($user->lang[$msg_text])) ? $user->lang[$msg_text] : $msg_text;
                        $msg_title = (!isset($msg_title)) ? $user->lang['INFORMATION'] : ((!empty($user->lang[$msg_title])) ? $user->lang[$msg_title] : $msg_title);

                        if (!defined('HEADER_INC'))
                        {
                                if (defined('ADMIN_START') || (defined('IN_ADMIN') && isset($user->data['session_admin']) && $user->data['session_admin']))
                                {
                                        adm_page_header($msg_title);
                                }
                                else
                                {
                                        page_header($msg_title);
                                }
                        }

                        $template->set_filenames(array(
                                'body' => 'message_body.html')
                        );

                        $template->assign_vars(array(
                                'MESSAGE_TITLE'         => $msg_title,
                                'MESSAGE_TEXT'          => $msg_text,
                                'S_USER_WARNING'        => ($errno == E_USER_WARNING) ? true : false,
                                'S_USER_NOTICE'         => ($errno == E_USER_NOTICE) ? true : false)
                        );

                        // We do not want the cron script to be called on error messages
                        define('IN_CRON', true);

                        if (defined('ADMIN_START') || (defined('IN_ADMIN') && isset($user->data['session_admin']) && $user->data['session_admin']))
                        {
                                adm_page_footer();
                        }
                        else
                        {
                                page_footer();
                        }

                        exit_handler();
                break;
        }

        // If we notice an error not handled here we pass this back to PHP by returning false
        // This may not work for all php versions
        return false;
}

/**
* Generate page header
*/
function page_header($page_title = '', $display_online_list = true)
{
        global $db, $config, $template, $SID, $_SID, $user, $auth;

        if (defined('HEADER_INC'))
        {
                return;
        }

        define('HEADER_INC', true);

        // gzip_compression
        if ($config['gzip_compress'])
        {
                if (@extension_loaded('zlib') && !headers_sent())
                {
                        ob_start('ob_gzhandler');
                }
        }

        // Generate logged in/logged out status
        if ($user->data['user_id'] != ANONYMOUS)
        {
                $u_login_logout = append_sid('ucp', 'mode=logout', true, $user->session_id);
                $l_login_logout = sprintf($user->lang['LOGOUT_USER'], $user->data['username']);
        }
        else
        {
                $u_login_logout = append_sid('ucp', 'mode=login');
                $l_login_logout = $user->lang['LOGIN'];
        }

        // Last visit date/time
        $s_last_visit = ($user->data['user_id'] != ANONYMOUS) ? $user->format_date($user->data['session_last_visit']) : '';

        // Get users online list ... if required
        $l_online_users = $online_userlist = $l_online_record = '';

        if ($config['load_online'] && $config['load_online_time'] && $display_online_list)
        {
                $logged_visible_online = $logged_hidden_online = $guests_online = $prev_user_id = 0;
                $prev_session_ip = $reading_sql = '';

                if (!empty($_REQUEST['f']))
                {
                        $f = request_var('f', 0);

                        $reading_sql = ' AND s.session_page ' . $db->sql_like_expression("{$db->any_char}_f_={$f}x{$db->any_char}");
                }

                // Get number of online guests
                if (!$config['load_online_guests'])
                {
                        if ($db->count_distinct)
                        {
                                $sql = 'SELECT COUNT(DISTINCT s.session_ip) as num_guests
                                        FROM ' . SESSIONS_TABLE . ' s
                                        WHERE s.session_user_id = ' . ANONYMOUS . '
                                                AND s.session_time >= ' . (time() - ($config['load_online_time'] * 60)) .
                                        $reading_sql;
                        }
                        else
                        {
                                $sql = 'SELECT COUNT(session_ip) as num_guests
                                        FROM (
                                                SELECT DISTINCT s.session_ip
                                                        FROM ' . SESSIONS_TABLE . ' s
                                                        WHERE s.session_user_id = ' . ANONYMOUS . '
                                                                AND s.session_time >= ' . (time() - ($config['load_online_time'] * 60)) .
                                                                $reading_sql .
                                        ')';
                        }
                        $result = $db->sql_query($sql);
                        $guests_online = (int) $db->sql_fetchfield('num_guests');
                        $db->sql_freeresult($result);
                }

                $sql = 'SELECT u.username, u.username_clean, u.user_id, u.user_type, u.user_allow_viewonline, u.user_colour, s.session_ip, s.session_viewonline
                        FROM ' . USERS_TABLE . ' u, ' . SESSIONS_TABLE . ' s
                        WHERE s.session_time >= ' . (time() - (intval($config['load_online_time']) * 60)) .
                                $reading_sql .
                                ((!$config['load_online_guests']) ? ' AND s.session_user_id <> ' . ANONYMOUS : '') . '
                                AND u.user_id = s.session_user_id
                        ORDER BY u.username_clean ASC, s.session_ip ASC';
                $result = $db->sql_query($sql);

                $prev_user_id = false;

                while ($row = $db->sql_fetchrow($result))
                {
                        // User is logged in and therefore not a guest
                        if ($row['user_id'] != ANONYMOUS)
                        {
                                // Skip multiple sessions for one user
                                if ($row['user_id'] != $prev_user_id)
                                {
                                        if ($row['session_viewonline'])
                                        {
                                                $logged_visible_online++;
                                        }
                                        else
                                        {
                                                $row['username'] = '<em>' . $row['username'] . '</em>';
                                                $logged_hidden_online++;
                                        }

                                        if (($row['session_viewonline']) || $auth->acl_get('u_viewonline'))
                                        {
                                                $user_online_link = get_username_string(($row['user_type'] <> USER_IGNORE) ? 'full' : 'no_profile', $row['user_id'], $row['username'], $row['user_colour']);
                                                $online_userlist .= ($online_userlist != '') ? ', ' . $user_online_link : $user_online_link;
                                        }
                                }

                                $prev_user_id = $row['user_id'];
                        }
                        else
                        {
                                // Skip multiple sessions for one user
                                if ($row['session_ip'] != $prev_session_ip)
                                {
                                        $guests_online++;
                                }
                        }

                        $prev_session_ip = $row['session_ip'];
                }
                $db->sql_freeresult($result);

                if (!$online_userlist)
                {
                        $online_userlist = $user->lang['NO_ONLINE_USERS'];
                }

                if (empty($_REQUEST['f']))
                {
                        $online_userlist = $user->lang['REGISTERED_USERS'] . ' ' . $online_userlist;
                }
                else
                {
                        $l_online = ($guests_online == 1) ? $user->lang['BROWSING_FORUM_GUEST'] : $user->lang['BROWSING_FORUM_GUESTS'];
                        $online_userlist = sprintf($l_online, $online_userlist, $guests_online);
                }

                $total_online_users = $logged_visible_online + $logged_hidden_online + $guests_online;

                if ($total_online_users > $config['record_online_users'])
                {
                        set_config('record_online_users', $total_online_users, true);
                        set_config('record_online_date', time(), true);
                }

                // Build online listing
                $vars_online = array(
                        'ONLINE'        => array('total_online_users', 'l_t_user_s'),
                        'REG'           => array('logged_visible_online', 'l_r_user_s'),
                        'HIDDEN'        => array('logged_hidden_online', 'l_h_user_s'),
                        'GUEST'         => array('guests_online', 'l_g_user_s')
                );

                foreach ($vars_online as $l_prefix => $var_ary)
                {
                        switch (${$var_ary[0]})
                        {
                                case 0:
                                        ${$var_ary[1]} = $user->lang[$l_prefix . '_USERS_ZERO_TOTAL'];
                                break;

                                case 1:
                                        ${$var_ary[1]} = $user->lang[$l_prefix . '_USER_TOTAL'];
                                break;

                                default:
                                        ${$var_ary[1]} = $user->lang[$l_prefix . '_USERS_TOTAL'];
                                break;
                        }
                }
                unset($vars_online);

                $l_online_users = sprintf($l_t_user_s, $total_online_users);
                $l_online_users .= sprintf($l_r_user_s, $logged_visible_online);
                $l_online_users .= sprintf($l_h_user_s, $logged_hidden_online);
                $l_online_users .= sprintf($l_g_user_s, $guests_online);

                $l_online_record = sprintf($user->lang['RECORD_ONLINE_USERS'], $config['record_online_users'], $user->format_date($config['record_online_date']));

                $l_online_time = ($config['load_online_time'] == 1) ? 'VIEW_ONLINE_TIME' : 'VIEW_ONLINE_TIMES';
                $l_online_time = sprintf($user->lang[$l_online_time], $config['load_online_time']);
        }
        else
        {
                $l_online_time = '';
        }

        $l_privmsgs_text = $l_privmsgs_text_unread = '';
        $s_privmsg_new = false;

        // Obtain number of new private messages if user is logged in
        if (isset($user->data['is_registered']) && $user->data['is_registered'])
        {
                if ($user->data['user_new_privmsg'])
                {
                        $l_message_new = ($user->data['user_new_privmsg'] == 1) ? $user->lang['NEW_PM'] : $user->lang['NEW_PMS'];
                        $l_privmsgs_text = sprintf($l_message_new, $user->data['user_new_privmsg']);

                        if (!$user->data['user_last_privmsg'] || $user->data['user_last_privmsg'] > $user->data['session_last_visit'])
                        {
                                $sql = 'UPDATE ' . USERS_TABLE . '
                                        SET user_last_privmsg = ' . $user->data['session_last_visit'] . '
                                        WHERE user_id = ' . $user->data['user_id'];
                                $db->sql_query($sql);

                                $s_privmsg_new = true;
                        }
                        else
                        {
                                $s_privmsg_new = false;
                        }
                }
                else
                {
                        $l_privmsgs_text = $user->lang['NO_NEW_PM'];
                        $s_privmsg_new = false;
                }

                $l_privmsgs_text_unread = '';

                if ($user->data['user_unread_privmsg'] && $user->data['user_unread_privmsg'] != $user->data['user_new_privmsg'])
                {
                        $l_message_unread = ($user->data['user_unread_privmsg'] == 1) ? $user->lang['UNREAD_PM'] : $user->lang['UNREAD_PMS'];
                        $l_privmsgs_text_unread = sprintf($l_message_unread, $user->data['user_unread_privmsg']);
                }
        }

        // Which timezone?
        $tz = ($user->data['user_id'] != ANONYMOUS) ? strval(doubleval($user->data['user_timezone'])) : strval(doubleval($config['board_timezone']));

        // Send a proper content-language to the output
        $user_lang = $user->lang['USER_LANG'];
        if (strpos($user_lang, '-x-') !== false)
        {
                $user_lang = substr($user_lang, 0, strpos($user_lang, '-x-'));
        }

        // The following assigns all _common_ variables that may be used at any point in a template.
        $template->assign_vars(array(
                'SITENAME'                                              => $config['sitename'],
                'SITE_DESCRIPTION'                              => $config['site_desc'],
                'PAGE_TITLE'                                    => $page_title,
                'SCRIPT_NAME'                                   => str_replace('.' . PHP_EXT, '', $user->page['page_name']),
                'LAST_VISIT_DATE'                               => sprintf($user->lang['YOU_LAST_VISIT'], $s_last_visit),
                'LAST_VISIT_YOU'                                => $s_last_visit,
                'CURRENT_TIME'                                  => sprintf($user->lang['CURRENT_TIME'], $user->format_date(time(), false, true)),
                'TOTAL_USERS_ONLINE'                    => $l_online_users,
                'LOGGED_IN_USER_LIST'                   => $online_userlist,
                'RECORD_USERS'                                  => $l_online_record,
                'PRIVATE_MESSAGE_INFO'                  => $l_privmsgs_text,
                'PRIVATE_MESSAGE_INFO_UNREAD'   => $l_privmsgs_text_unread,

                'S_USER_NEW_PRIVMSG'                    => $user->data['user_new_privmsg'],
                'S_USER_UNREAD_PRIVMSG'                 => $user->data['user_unread_privmsg'],

                'SID'                           => $SID,
                '_SID'                          => $_SID,
                'SESSION_ID'            => $user->session_id,
                'ROOT_PATH'                     => PHPBB_ROOT_PATH,

                'L_LOGIN_LOGOUT'        => $l_login_logout,
                'L_INDEX'                       => $user->lang['FORUM_INDEX'],
                'L_ONLINE_EXPLAIN'      => $l_online_time,

                'U_PRIVATEMSGS'                 => append_sid('ucp', 'i=pm&amp;folder=inbox'),
                'U_RETURN_INBOX'                => append_sid('ucp', 'i=pm&amp;folder=inbox'),
                'U_POPUP_PM'                    => append_sid('ucp', 'i=pm&amp;mode=popup'),
                'UA_POPUP_PM'                   => addslashes(append_sid('ucp', 'i=pm&amp;mode=popup')),
                'U_MEMBERLIST'                  => append_sid('memberlist'),
                'U_VIEWONLINE'                  => ($auth->acl_gets('u_viewprofile', 'a_user', 'a_useradd', 'a_userdel')) ? append_sid('viewonline') : '',
                'U_LOGIN_LOGOUT'                => $u_login_logout,
                'U_INDEX'                               => append_sid('index'),
                'U_SEARCH'                              => append_sid('search'),
                'U_REGISTER'                    => append_sid('ucp', 'mode=register'),
                'U_PROFILE'                             => append_sid('ucp'),
                'U_MODCP'                               => append_sid('mcp', false, true, $user->session_id),
                'U_FAQ'                                 => append_sid('faq'),
                'U_SEARCH_SELF'                 => append_sid('search', 'search_id=egosearch'),
                'U_SEARCH_NEW'                  => append_sid('search', 'search_id=newposts'),
                'U_SEARCH_UNANSWERED'   => append_sid('search', 'search_id=unanswered'),
                'U_SEARCH_ACTIVE_TOPICS'=> append_sid('search', 'search_id=active_topics'),
                'U_DELETE_COOKIES'              => append_sid('ucp', 'mode=delete_cookies'),
                'U_TEAM'                                => append_sid('memberlist', 'mode=leaders'),
                'U_RESTORE_PERMISSIONS' => ($user->data['user_perm_from'] && $auth->acl_get('a_switchperm')) ? append_sid('ucp', 'mode=restore_perm') : '',

                'S_USER_LOGGED_IN'              => ($user->data['user_id'] != ANONYMOUS) ? true : false,
                'S_AUTOLOGIN_ENABLED'   => ($config['allow_autologin']) ? true : false,
                'S_BOARD_DISABLED'              => ($config['board_disable']) ? true : false,
                'S_REGISTERED_USER'             => $user->data['is_registered'],
                'S_IS_BOT'                              => $user->data['is_bot'],
                'S_IN_SEARCH'                   => false,
                'S_VIEWTOPIC'                   => false,
                'S_VIEWFORUM'                   => false,
                'S_USER_PM_POPUP'               => $user->optionget('popuppm'),
                'S_USER_LANG'                   => $user_lang,
                'S_USER_BROWSER'                => (isset($user->data['session_browser'])) ? $user->data['session_browser'] : $user->lang['UNKNOWN_BROWSER'],
                'S_USERNAME'                    => $user->data['username'],
                'S_CONTENT_DIRECTION'   => $user->lang['DIRECTION'],
                'S_CONTENT_FLOW_BEGIN'  => ($user->lang['DIRECTION'] == 'ltr') ? 'left' : 'right',
                'S_CONTENT_FLOW_END'    => ($user->lang['DIRECTION'] == 'ltr') ? 'right' : 'left',
                'S_CONTENT_ENCODING'    => 'UTF-8',
                'S_TIMEZONE'                    => ($user->data['user_dst'] || ($user->data['user_id'] == ANONYMOUS && $config['board_dst'])) ? sprintf($user->lang['ALL_TIMES'], $user->lang['tz'][$tz], $user->lang['tz']['dst']) : sprintf($user->lang['ALL_TIMES'], $user->lang['tz'][$tz], ''),
                'S_DISPLAY_ONLINE_LIST' => ($l_online_time) ? 1 : 0,
                'S_DISPLAY_SEARCH'              => (!$config['load_search']) ? 0 : (isset($auth) ? ($auth->acl_get('u_search') && $auth->acl_getf_global('f_search')) : 1),
                'S_DISPLAY_PM'                  => ($config['allow_privmsg'] && $user->data['is_registered'] && ($auth->acl_get('u_readpm') || $auth->acl_get('u_sendpm'))) ? true : false,
                'S_DISPLAY_MEMBERLIST'  => (isset($auth)) ? $auth->acl_get('u_viewprofile') : 0,
                'S_NEW_PM'                              => ($s_privmsg_new) ? 1 : 0,
                'S_REGISTER_ENABLED'    => ($config['require_activation'] != USER_ACTIVATION_DISABLE) ? true : false,

                'T_THEME_PATH'                  => PHPBB_ROOT_PATH . 'styles/' . $user->theme['theme_path'] . '/theme',
                'T_TEMPLATE_PATH'               => PHPBB_ROOT_PATH . 'styles/' . $user->theme['template_path'] . '/template',
                'T_IMAGESET_PATH'               => PHPBB_ROOT_PATH . 'styles/' . $user->theme['imageset_path'] . '/imageset',
                'T_IMAGESET_LANG_PATH'  => PHPBB_ROOT_PATH . 'styles/' . $user->theme['imageset_path'] . '/imageset/' . $user->data['user_lang'],
                'T_IMAGES_PATH'                 => PHPBB_ROOT_PATH . 'images/',
                'T_SMILIES_PATH'                => PHPBB_ROOT_PATH . $config['smilies_path'] . '/',
                'T_AVATAR_PATH'                 => PHPBB_ROOT_PATH . $config['avatar_path'] . '/',
                'T_AVATAR_GALLERY_PATH' => PHPBB_ROOT_PATH . $config['avatar_gallery_path'] . '/',
                'T_ICONS_PATH'                  => PHPBB_ROOT_PATH . $config['icons_path'] . '/',
                'T_RANKS_PATH'                  => PHPBB_ROOT_PATH . $config['ranks_path'] . '/',
                'T_UPLOAD_PATH'                 => PHPBB_ROOT_PATH . $config['upload_path'] . '/',
                'T_STYLESHEET_LINK'             => (!$user->theme['theme_storedb']) ? PHPBB_ROOT_PATH . 'styles/' . $user->theme['theme_path'] . '/theme/stylesheet.css' : PHPBB_ROOT_PATH . 'style.' . PHP_EXT . "?sid=$user->session_id&amp;id=" . $user->theme['style_id'] . '&amp;lang=' . $user->data['user_lang'], //PHPBB_ROOT_PATH . "store/{$user->theme['theme_id']}_{$user->theme['imageset_id']}_{$user->lang_name}.css"
                'T_STYLESHEET_NAME'             => $user->theme['theme_name'],

                'SITE_LOGO_IMG'                 => $user->img('site_logo'))
        );

        // application/xhtml+xml not used because of IE
        header('Content-type: text/html; charset=UTF-8');

        header('Cache-Control: private, no-cache="set-cookie"');
        header('Expires: 0');
        header('Pragma: no-cache');

        return;
}

/**
* Generate page footer
*/
function page_footer($run_cron = true)
{
        global $db, $config, $template, $user, $auth, $cache, $starttime;

        // Output page creation time
        if (defined('DEBUG'))
        {
                $mtime = explode(' ', microtime());
                $totaltime = $mtime[0] + $mtime[1] - $starttime;

                if (!empty($_REQUEST['explain']) && $auth->acl_get('a_') && defined('DEBUG_EXTRA') && method_exists($db, 'sql_report'))
                {
                        $db->sql_report('display');
                }

                $debug_output = sprintf('Time : %.3fs | ' . $db->sql_num_queries() . ' Queries | GZIP : ' . (($config['gzip_compress']) ? 'On' : 'Off') . (($user->load) ? ' | Load : ' . $user->load : ''), $totaltime);

                if ($auth->acl_get('a_') && defined('DEBUG_EXTRA'))
                {
                        if (function_exists('memory_get_usage'))
                        {
                                if ($memory_usage = memory_get_usage())
                                {
                                        global $base_memory_usage;
                                        $memory_usage -= $base_memory_usage;
                                        $memory_usage = get_formatted_filesize($memory_usage);

                                        $debug_output .= ' | Memory Usage: ' . $memory_usage;
                                }
                        }

                        $debug_output .= ' | <a href="' . build_url() . '&amp;explain=1">Explain</a>';
                }
        }

        $template->assign_vars(array(
                'DEBUG_OUTPUT'                  => (defined('DEBUG')) ? $debug_output : '',
                'TRANSLATION_INFO'              => (!empty($user->lang['TRANSLATION_INFO'])) ? $user->lang['TRANSLATION_INFO'] : '',

                'U_ACP' => ($auth->acl_get('a_') && $user->data['is_registered']) ? append_sid(CONFIG_ADM_FOLDER . '/index', false, true, $user->session_id) : '')
        );

        // Call cron-type script
        if (!defined('IN_CRON') && $run_cron && !$config['board_disable'])
        {
                $cron_type = '';

                if (time() - $config['queue_interval'] > $config['last_queue_run'] && !defined('IN_ADMIN') && file_exists(PHPBB_ROOT_PATH . 'cache/queue.' . PHP_EXT))
                {
                        // Process email queue
                        $cron_type = 'queue';
                }
                else if (method_exists($cache, 'tidy') && time() - $config['cache_gc'] > $config['cache_last_gc'])
                {
                        // Tidy the cache
                        $cron_type = 'tidy_cache';
                }
                else if (time() - $config['warnings_gc'] > $config['warnings_last_gc'])
                {
                        $cron_type = 'tidy_warnings';
                }
                else if (time() - $config['database_gc'] > $config['database_last_gc'])
                {
                        // Tidy the database
                        $cron_type = 'tidy_database';
                }
                else if (time() - $config['search_gc'] > $config['search_last_gc'])
                {
                        // Tidy the search
                        $cron_type = 'tidy_search';
                }
                else if (time() - $config['session_gc'] > $config['session_last_gc'])
                {
                        $cron_type = 'tidy_sessions';
                }

                if ($cron_type)
                {
                        $template->assign_var('RUN_CRON_TASK', '<img src="' . append_sid('cron', 'cron_type=' . $cron_type) . '" width="1" height="1" alt="cron" />');
                }
        }

        $template->display('body');

        garbage_collection();
        exit_handler();
}

/**
* Closing the cache object and the database
* Cool function name, eh? We might want to add operations to it later
*/
function garbage_collection()
{
        global $cache, $db;

        // Unload cache, must be done before the DB connection if closed
        if (!empty($cache))
        {
                $cache->unload();
        }

        // Close our DB connection.
        if (!empty($db))
        {
                $db->sql_close();
        }
}

/**
* Handler for exit calls in phpBB.
* This function supports hooks.
*
* Note: This function is called after the template has been outputted.
*/
function exit_handler()
{
        global $phpbb_hook, $config;

        if (!empty($phpbb_hook) && $phpbb_hook->call_hook(__FUNCTION__))
        {
                if ($phpbb_hook->hook_return(__FUNCTION__))
                {
                        return $phpbb_hook->hook_return_result(__FUNCTION__);
                }
        }

        // As a pre-caution... some setups display a blank page if the flush() is not there.
        (!$config['gzip_compress']) ? @flush() : @ob_flush();

        exit;
}

/**
* Handler for init calls in phpBB. This function is called in user::setup();
* This function supports hooks.
*/
function phpbb_user_session_handler()
{
        global $phpbb_hook;

        if (!empty($phpbb_hook) && $phpbb_hook->call_hook(__FUNCTION__))
        {
                if ($phpbb_hook->hook_return(__FUNCTION__))
                {
                        return $phpbb_hook->hook_return_result(__FUNCTION__);
                }
        }

        return;
}

?>