r4068 mkA(): new helper function

[racktables] / inc / functions.php

<?php
/*
*
*  This file is a library of computational functions for RackTables.
*
*/

$loclist[0] = 'front';
$loclist[1] = 'interior';
$loclist[2] = 'rear';
$loclist['front'] = 0;
$loclist['interior'] = 1;
$loclist['rear'] = 2;
$template[0] = array (TRUE, TRUE, TRUE);
$template[1] = array (TRUE, TRUE, FALSE);
$template[2] = array (FALSE, TRUE, TRUE);
$template[3] = array (TRUE, FALSE, FALSE);
$template[4] = array (FALSE, TRUE, FALSE);
$template[5] = array (FALSE, FALSE, TRUE);
$templateWidth[0] = 3;
$templateWidth[1] = 2;
$templateWidth[2] = 2;
$templateWidth[3] = 1;
$templateWidth[4] = 1;
$templateWidth[5] = 1;

define ('TAB_REMEMBER_TIMEOUT', 300);

// Entity type by page number mapping is 1:1 atm, but may change later.
$etype_by_pageno = array
(
        'ipv4net' => 'ipv4net',
        'ipv6net' => 'ipv6net',
        'ipv4rspool' => 'ipv4rspool',
        'ipv4vs' => 'ipv4vs',
        'object' => 'object',
        'rack' => 'rack',
        'user' => 'user',
        'file' => 'file',
);

// Rack thumbnail image width summands: "front", "interior" and "rear" elements w/o surrounding border.
$rtwidth = array
(
        0 => 9,
        1 => 21,
        2 => 9
);

$netmaskbylen = array
(
        32 => '255.255.255.255',
        31 => '255.255.255.254',
        30 => '255.255.255.252',
        29 => '255.255.255.248',
        28 => '255.255.255.240',
        27 => '255.255.255.224',
        26 => '255.255.255.192',
        25 => '255.255.255.128',
        24 => '255.255.255.0',
        23 => '255.255.254.0',
        22 => '255.255.252.0',
        21 => '255.255.248.0',
        20 => '255.255.240.0',
        19 => '255.255.224.0',
        18 => '255.255.192.0',
        17 => '255.255.128.0',
        16 => '255.255.0.0',
        15 => '255.254.0.0',
        14 => '255.252.0.0',
        13 => '255.248.0.0',
        12 => '255.240.0.0',
        11 => '255.224.0.0',
        10 => '255.192.0.0',
        9 => '255.128.0.0',
        8 => '255.0.0.0',
        7 => '254.0.0.0',
        6 => '252.0.0.0',
        5 => '248.0.0.0',
        4 => '240.0.0.0',
        3 => '224.0.0.0',
        2 => '192.0.0.0',
        1 => '128.0.0.0'
);

$wildcardbylen = array
(
        32 => '0.0.0.0',
        31 => '0.0.0.1',
        30 => '0.0.0.3',
        29 => '0.0.0.7',
        28 => '0.0.0.15',
        27 => '0.0.0.31',
        26 => '0.0.0.63',
        25 => '0.0.0.127',
        24 => '0.0.0.255',
        23 => '0.0.1.255',
        22 => '0.0.3.255',
        21 => '0.0.7.255',
        20 => '0.0.15.255',
        19 => '0.0.31.255',
        18 => '0.0.63.255',
        17 => '0.0.127.255',
        16 => '0.0.255.25',
        15 => '0.1.255.255',
        14 => '0.3.255.255',
        13 => '0.7.255.255',
        12 => '0.15.255.255',
        11 => '0.31.255.255',
        10 => '0.63.255.255',
        9 => '0.127.255.255',
        8 => '0.255.255.255',
        7 => '1.255.255.255',
        6 => '3.255.255.255',
        5 => '7.255.255.255',
        4 => '15.255.255.255',
        3 => '31.255.255.255',
        2 => '63.255.255.255',
        1 => '127.255.255.255'
);

// This function assures that specified argument was passed
// and is a number greater than zero.
function assertUIntArg ($argname, $allow_zero = FALSE)
{
        if (!isset ($_REQUEST[$argname]))
                throw new InvalidRequestArgException($argname, '', 'parameter is missing');
        if (!is_numeric ($_REQUEST[$argname]))
                throw new InvalidRequestArgException($argname, $_REQUEST[$argname], 'parameter is not a number');
        if ($_REQUEST[$argname] < 0)
                throw new InvalidRequestArgException($argname, $_REQUEST[$argname], 'parameter is less than zero');
        if (!$allow_zero and $_REQUEST[$argname] == 0)
                throw new InvalidRequestArgException($argname, $_REQUEST[$argname], 'parameter is zero');
}

// This function assures that specified argument was passed
// and is a non-empty string.
function assertStringArg ($argname, $ok_if_empty = FALSE)
{
        if (!isset ($_REQUEST[$argname]))
                throw new InvalidRequestArgException($argname, '', 'parameter is missing');
        if (!is_string ($_REQUEST[$argname]))
                throw new InvalidRequestArgException($argname, $_REQUEST[$argname], 'parameter is not a string');
        if (!$ok_if_empty and !strlen ($_REQUEST[$argname]))
                throw new InvalidRequestArgException($argname, $_REQUEST[$argname], 'parameter is an empty string');
}

function assertBoolArg ($argname, $ok_if_empty = FALSE)
{
        if (!isset ($_REQUEST[$argname]))
                throw new InvalidRequestArgException($argname, '', 'parameter is missing');
        if (!is_string ($_REQUEST[$argname]) or $_REQUEST[$argname] != 'on')
                throw new InvalidRequestArgException($argname, $_REQUEST[$argname], 'parameter is not a string');
        if (!$ok_if_empty and !strlen ($_REQUEST[$argname]))
                throw new InvalidRequestArgException($argname, $_REQUEST[$argname], 'parameter is an empty string');
}

// function returns IPv6Address object, null if arg is correct IPv4, or throws an exception
function assertIPArg ($argname, $ok_if_empty = FALSE)
{
        assertStringArg ($argname, $ok_if_empty);
        $ip = $_REQUEST[$argname];
        if (FALSE !== strpos ($ip, ':'))
        {
                $v6address = new IPv6Address;
                $result = $v6address->parse ($ip);
                $ret = $v6address;
        }
        else
        {
                $result = long2ip (ip2long ($ip)) === $ip;
                $ret = NULL;
        }
        if (! $result)
                throw new InvalidRequestArgException ($argname, $ip, 'parameter is not a valid IPv4 or IPv6 address');
        return $ret;
}

function assertIPv4Arg ($argname, $ok_if_empty = FALSE)
{
        assertStringArg ($argname, $ok_if_empty);
        if (strlen ($_REQUEST[$argname]) and long2ip (ip2long ($_REQUEST[$argname])) !== $_REQUEST[$argname])
                throw new InvalidRequestArgException($argname, $_REQUEST[$argname], 'parameter is not a valid ipv4 address');
}

// function returns IPv6Address object, or throws an exception
function assertIPv6Arg ($argname, $ok_if_empty = FALSE)
{
        assertStringArg ($argname, $ok_if_empty);
        $ipv6 = new IPv6Address;
        if (strlen ($_REQUEST[$argname]) and ! $ok_if_empty and ! $ipv6->parse ($_REQUEST[$argname]))
                throw new InvalidRequestArgException($argname, $_REQUEST[$argname], 'parameter is not a valid ipv6 address');
        return $ipv6;
}

function assertPCREArg ($argname)
{
        assertStringArg ($argname, TRUE); // empty pattern is Ok
        if (FALSE === preg_match ($_REQUEST[$argname], 'test'))
                throw new InvalidRequestArgException($argname, $_REQUEST[$argname], 'PCRE validation failed');
}

// Objects of some types should be explicitly shown as
// anonymous (labelless). This function is a single place where the
// decision about displayed name is made.
function setDisplayedName (&$cell)
{
        if ($cell['name'] != '')
                $cell['dname'] = $cell['name'];
        else
        {
                $cell['atags'][] = array ('tag' => '$nameless');
                if (considerConfiguredConstraint ($cell, 'NAMEWARN_LISTSRC'))
                        $cell['dname'] = 'ANONYMOUS ' . decodeObjectType ($cell['objtype_id'], 'o');
                else
                        $cell['dname'] = '[' . decodeObjectType ($cell['objtype_id'], 'o') . ']';
        }
}

// This function finds height of solid rectangle of atoms, which are all
// assigned to the same object. Rectangle base is defined by specified
// template.
function rectHeight ($rackData, $startRow, $template_idx)
{
        $height = 0;
        // The first met object_id is used to match all the folowing IDs.
        $object_id = 0;
        global $template;
        do
        {
                for ($locidx = 0; $locidx < 3; $locidx++)
                {
                        // At least one value in template is TRUE, but the following block
                        // can meet 'skipped' atoms. Let's ensure we have something after processing
                        // the first row.
                        if ($template[$template_idx][$locidx])
                        {
                                if (isset ($rackData[$startRow - $height][$locidx]['skipped']))
                                        break 2;
                                if (isset ($rackData[$startRow - $height][$locidx]['rowspan']))
                                        break 2;
                                if (isset ($rackData[$startRow - $height][$locidx]['colspan']))
                                        break 2;
                                if ($rackData[$startRow - $height][$locidx]['state'] != 'T')
                                        break 2;
                                if ($object_id == 0)
                                        $object_id = $rackData[$startRow - $height][$locidx]['object_id'];
                                if ($object_id != $rackData[$startRow - $height][$locidx]['object_id'])
                                        break 2;
                        }
                }
                // If the first row can't offer anything, bail out.
                if ($height == 0 and $object_id == 0)
                        break;
                $height++;
        }
        while ($startRow - $height > 0);
#       echo "for startRow==${startRow} and template==(" . ($template[$template_idx][0] ? 'T' : 'F');
#       echo ', ' . ($template[$template_idx][1] ? 'T' : 'F') . ', ' . ($template[$template_idx][2] ? 'T' : 'F');
#       echo ") height==${height}<br>\n";
        return $height;
}

// This function marks atoms to be avoided by rectHeight() and assigns rowspan/colspan
// attributes.
function markSpan (&$rackData, $startRow, $maxheight, $template_idx)
{
        global $template, $templateWidth;
        $colspan = 0;
        for ($height = 0; $height < $maxheight; $height++)
        {
                for ($locidx = 0; $locidx < 3; $locidx++)
                {
                        if ($template[$template_idx][$locidx])
                        {
                                // Add colspan/rowspan to the first row met and mark the following ones to skip.
                                // Explicitly show even single-cell spanned atoms, because rectHeight()
                                // is expeciting this data for correct calculation.
                                if ($colspan != 0)
                                        $rackData[$startRow - $height][$locidx]['skipped'] = TRUE;
                                else
                                {
                                        $colspan = $templateWidth[$template_idx];
                                        if ($colspan >= 1)
                                                $rackData[$startRow - $height][$locidx]['colspan'] = $colspan;
                                        if ($maxheight >= 1)
                                                $rackData[$startRow - $height][$locidx]['rowspan'] = $maxheight;
                                }
                        }
                }
        }
        return;
}

// This function sets rowspan/solspan/skipped atom attributes for renderRack()
// What we actually have to do is to find _all_ possible rectangles for each unit
// and then select the widest of those with the maximal square.
function markAllSpans (&$rackData)
{
        for ($i = $rackData['height']; $i > 0; $i--)
                while (markBestSpan ($rackData, $i));
}

// Calculate height of 6 possible span templates (array is presorted by width
// descending) and mark the best (if any).
function markBestSpan (&$rackData, $i)
{
        global $template, $templateWidth;
        for ($j = 0; $j < 6; $j++)
        {
                $height[$j] = rectHeight ($rackData, $i, $j);
                $square[$j] = $height[$j] * $templateWidth[$j];
        }
        // find the widest rectangle of those with maximal height
        $maxsquare = max ($square);
        if (!$maxsquare)
                return FALSE;
        $best_template_index = 0;
        for ($j = 0; $j < 6; $j++)
                if ($square[$j] == $maxsquare)
                {
                        $best_template_index = $j;
                        $bestheight = $height[$j];
                        break;
                }
        // distribute span marks
        markSpan ($rackData, $i, $bestheight, $best_template_index);
        return TRUE;
}

// We can mount 'F' atoms and unmount our own 'T' atoms.
function applyObjectMountMask (&$rackData, $object_id)
{
        for ($unit_no = $rackData['height']; $unit_no > 0; $unit_no--)
                for ($locidx = 0; $locidx < 3; $locidx++)
                        switch ($rackData[$unit_no][$locidx]['state'])
                        {
                                case 'F':
                                        $rackData[$unit_no][$locidx]['enabled'] = TRUE;
                                        break;
                                case 'T':
                                        $rackData[$unit_no][$locidx]['enabled'] = ($rackData[$unit_no][$locidx]['object_id'] == $object_id);
                                        break;
                                default:
                                        $rackData[$unit_no][$locidx]['enabled'] = FALSE;
                        }
}

// Design change means transition between 'F' and 'A' and back.
function applyRackDesignMask (&$rackData)
{
        for ($unit_no = $rackData['height']; $unit_no > 0; $unit_no--)
                for ($locidx = 0; $locidx < 3; $locidx++)
                        switch ($rackData[$unit_no][$locidx]['state'])
                        {
                                case 'F':
                                case 'A':
                                        $rackData[$unit_no][$locidx]['enabled'] = TRUE;
                                        break;
                                default:
                                        $rackData[$unit_no][$locidx]['enabled'] = FALSE;
                        }
}

// The same for 'F' and 'U'.
function applyRackProblemMask (&$rackData)
{
        for ($unit_no = $rackData['height']; $unit_no > 0; $unit_no--)
                for ($locidx = 0; $locidx < 3; $locidx++)
                        switch ($rackData[$unit_no][$locidx]['state'])
                        {
                                case 'F':
                                case 'U':
                                        $rackData[$unit_no][$locidx]['enabled'] = TRUE;
                                        break;
                                default:
                                        $rackData[$unit_no][$locidx]['enabled'] = FALSE;
                        }
}

// This function highlights specified object (and removes previous highlight).
function highlightObject (&$rackData, $object_id)
{
        for ($unit_no = $rackData['height']; $unit_no > 0; $unit_no--)
                for ($locidx = 0; $locidx < 3; $locidx++)
                        if
                        (
                                $rackData[$unit_no][$locidx]['state'] == 'T' and
                                $rackData[$unit_no][$locidx]['object_id'] == $object_id
                        )
                                $rackData[$unit_no][$locidx]['hl'] = 'h';
                        else
                                unset ($rackData[$unit_no][$locidx]['hl']);
}

// This function marks atoms to selected or not depending on their current state.
function markupAtomGrid (&$data, $checked_state)
{
        for ($unit_no = $data['height']; $unit_no > 0; $unit_no--)
                for ($locidx = 0; $locidx < 3; $locidx++)
                {
                        if (!($data[$unit_no][$locidx]['enabled'] === TRUE))
                                continue;
                        if ($data[$unit_no][$locidx]['state'] == $checked_state)
                                $data[$unit_no][$locidx]['checked'] = ' checked';
                        else
                                $data[$unit_no][$locidx]['checked'] = '';
                }
}

// This function is almost a clone of processGridForm(), but doesn't save anything to database
// Return value is the changed rack data.
// Here we assume that correct filter has already been applied, so we just
// set or unset checkbox inputs w/o changing atom state.
function mergeGridFormToRack (&$rackData)
{
        $rack_id = $rackData['id'];
        for ($unit_no = $rackData['height']; $unit_no > 0; $unit_no--)
                for ($locidx = 0; $locidx < 3; $locidx++)
                {
                        if ($rackData[$unit_no][$locidx]['enabled'] != TRUE)
                                continue;
                        $inputname = "atom_${rack_id}_${unit_no}_${locidx}";
                        if (isset ($_REQUEST[$inputname]) and $_REQUEST[$inputname] == 'on')
                                $rackData[$unit_no][$locidx]['checked'] = ' checked';
                        else
                                $rackData[$unit_no][$locidx]['checked'] = '';
                }
}

// netmask conversion from length to number
function binMaskFromDec ($maskL)
{
        $map_straight = array (
                0  => 0x00000000,
                1  => 0x80000000,
                2  => 0xc0000000,
                3  => 0xe0000000,
                4  => 0xf0000000,
                5  => 0xf8000000,
                6  => 0xfc000000,
                7  => 0xfe000000,
                8  => 0xff000000,
                9  => 0xff800000,
                10 => 0xffc00000,
                11 => 0xffe00000,
                12 => 0xfff00000,
                13 => 0xfff80000,
                14 => 0xfffc0000,
                15 => 0xfffe0000,
                16 => 0xffff0000,
                17 => 0xffff8000,
                18 => 0xffffc000,
                19 => 0xffffe000,
                20 => 0xfffff000,
                21 => 0xfffff800,
                22 => 0xfffffc00,
                23 => 0xfffffe00,
                24 => 0xffffff00,
                25 => 0xffffff80,
                26 => 0xffffffc0,
                27 => 0xffffffe0,
                28 => 0xfffffff0,
                29 => 0xfffffff8,
                30 => 0xfffffffc,
                31 => 0xfffffffe,
                32 => 0xffffffff,
        );
        return $map_straight[$maskL];
}

// complementary value
function binInvMaskFromDec ($maskL)
{
        $map_compl = array (
                0  => 0xffffffff,
                1  => 0x7fffffff,
                2  => 0x3fffffff,
                3  => 0x1fffffff,
                4  => 0x0fffffff,
                5  => 0x07ffffff,
                6  => 0x03ffffff,
                7  => 0x01ffffff,
                8  => 0x00ffffff,
                9  => 0x007fffff,
                10 => 0x003fffff,
                11 => 0x001fffff,
                12 => 0x000fffff,
                13 => 0x0007ffff,
                14 => 0x0003ffff,
                15 => 0x0001ffff,
                16 => 0x0000ffff,
                17 => 0x00007fff,
                18 => 0x00003fff,
                19 => 0x00001fff,
                20 => 0x00000fff,
                21 => 0x000007ff,
                22 => 0x000003ff,
                23 => 0x000001ff,
                24 => 0x000000ff,
                25 => 0x0000007f,
                26 => 0x0000003f,
                27 => 0x0000001f,
                28 => 0x0000000f,
                29 => 0x00000007,
                30 => 0x00000003,
                31 => 0x00000001,
                32 => 0x00000000,
        );
        return $map_compl[$maskL];
}

// This function looks up 'has_problems' flag for 'T' atoms
// and modifies 'hl' key. May be, this should be better done
// in amplifyCell(). We don't honour 'skipped' key, because
// the function is also used for thumb creation.
function markupObjectProblems (&$rackData)
{
        for ($i = $rackData['height']; $i > 0; $i--)
                for ($locidx = 0; $locidx < 3; $locidx++)
                        if ($rackData[$i][$locidx]['state'] == 'T')
                        {
                                $object = spotEntity ('object', $rackData[$i][$locidx]['object_id']);
                                if ($object['has_problems'] == 'yes')
                                {
                                        // Object can be already highlighted.
                                        if (isset ($rackData[$i][$locidx]['hl']))
                                                $rackData[$i][$locidx]['hl'] = $rackData[$i][$locidx]['hl'] . 'w';
                                        else
                                                $rackData[$i][$locidx]['hl'] = 'w';
                                }
                        }
}

// Return a uniformly (010203040506 or 0102030405060708) formatted address, if it is present
// in the provided string, an empty string for an empty string or NULL for error.
function l2addressForDatabase ($string)
{
        $string = strtoupper ($string);
        switch (TRUE)
        {
                case ($string == '' or preg_match (RE_L2_SOLID, $string) or preg_match (RE_L2_WWN_SOLID, $string)):
                        return $string;
                case (preg_match (RE_L2_IFCFG, $string) or preg_match (RE_L2_WWN_COLON, $string)):
                        // reformat output of SunOS ifconfig
                        $ret = '';
                        foreach (explode (':', $string) as $byte)
                                $ret .= (strlen ($byte) == 1 ? '0' : '') . $byte;
                        return $ret;
                case (preg_match (RE_L2_CISCO, $string)):
                        return str_replace ('.', '', $string);
                case (preg_match (RE_L2_HUAWEI, $string)):
                        return str_replace ('-', '', $string);
                case (preg_match (RE_L2_IPCFG, $string) or preg_match (RE_L2_WWN_HYPHEN, $string)):
                        return str_replace ('-', '', $string);
                default:
                        return NULL;
        }
}

function l2addressFromDatabase ($string)
{
        switch (strlen ($string))
        {
                case 12: // Ethernet
                case 16: // FireWire/Fibre Channel
                        $ret = implode (':', str_split ($string, 2));
                        break;
                default:
                        $ret = $string;
                        break;
        }
        return $ret;
}

// The following 2 functions return previous and next rack IDs for
// a given rack ID. The order of racks is the same as in renderRackspace()
// or renderRow().
function getPrevIDforRack ($row_id, $rack_id)
{
        $rackList = listCells ('rack', $row_id);
        doubleLink ($rackList);
        if (isset ($rackList[$rack_id]['prev_key']))
                return $rackList[$rack_id]['prev_key'];
        return NULL;
}

function getNextIDforRack ($row_id, $rack_id)
{
        $rackList = listCells ('rack', $row_id);
        doubleLink ($rackList);
        if (isset ($rackList[$rack_id]['next_key']))
                return $rackList[$rack_id]['next_key'];
        return NULL;
}

// This function finds previous and next array keys for each array key and
// modifies its argument accordingly.
function doubleLink (&$array)
{
        $prev_key = NULL;
        foreach (array_keys ($array) as $key)
        {
                if ($prev_key)
                {
                        $array[$key]['prev_key'] = $prev_key;
                        $array[$prev_key]['next_key'] = $key;
                }
                $prev_key = $key;
        }
}

function sortTokenize ($a, $b)
{
        $aold='';
        while ($a != $aold)
        {
                $aold=$a;
                $a = preg_replace('/[^a-zA-Z0-9]/',' ',$a);
                $a = preg_replace('/([0-9])([a-zA-Z])/','\\1 \\2',$a);
                $a = preg_replace('/([a-zA-Z])([0-9])/','\\1 \\2',$a);
        }

        $bold='';
        while ($b != $bold)
        {
                $bold=$b;
                $b = preg_replace('/[^a-zA-Z0-9]/',' ',$b);
                $b = preg_replace('/([0-9])([a-zA-Z])/','\\1 \\2',$b);
                $b = preg_replace('/([a-zA-Z])([0-9])/','\\1 \\2',$b);
        }



        $ar = explode(' ', $a);
        $br = explode(' ', $b);
        for ($i=0; $i<count($ar) && $i<count($br); $i++)
        {
                $ret = 0;
                if (is_numeric($ar[$i]) and is_numeric($br[$i]))
                        $ret = ($ar[$i]==$br[$i])?0:($ar[$i]<$br[$i]?-1:1);
                else
                        $ret = strcasecmp($ar[$i], $br[$i]);
                if ($ret != 0)
                        return $ret;
        }
        if ($i<count($ar))
                return 1;
        if ($i<count($br))
                return -1;
        return 0;
}

// This function returns an array of single element of object's FQDN attribute,
// if FQDN is set. The next choice is object's common name, if it looks like a
// hostname. Otherwise an array of all 'regular' IP addresses of the
// object is returned (which may appear 0 and more elements long).
function findAllEndpoints ($object_id, $fallback = '')
{
        foreach (getAttrValues ($object_id) as $record)
                if ($record['id'] == 3 && strlen ($record['value'])) // FQDN
                        return array ($record['value']);
        $regular = array();
        foreach (getObjectIPv4Allocations ($object_id) as $dottedquad => $alloc)
                if ($alloc['type'] == 'regular')
                        $regular[] = $dottedquad;
        if (!count ($regular) && strlen ($fallback))
                return array ($fallback);
        return $regular;
}

// Some records in the dictionary may be written as plain text or as Wiki
// link in the following syntax:
// 1. word
// 2. [[word URL]] // FIXME: this isn't working
// 3. [[word word word | URL]]
// This function parses the line and returns text suitable for either A
// (rendering <A HREF>) or O (for <OPTION>).
function parseWikiLink ($line, $which)
{
        if (preg_match ('/^\[\[.+\]\]$/', $line) == 0)
        {
                // always strip the marker for A-data, but let cookOptgroup()
                // do this later (otherwise it can't sort groups out)
                if ($which == 'a')
                        return preg_replace ('/^.+%GSKIP%/', '', preg_replace ('/^(.+)%GPASS%/', '\\1 ', $line));
                else
                        return $line;
        }
        $line = preg_replace ('/^\[\[(.+)\]\]$/', '$1', $line);
        $s = explode ('|', $line);
        $o_value = trim ($s[0]);
        if ($which == 'o')
                return $o_value;
        $o_value = preg_replace ('/^.+%GSKIP%/', '', preg_replace ('/^(.+)%GPASS%/', '\\1 ', $o_value));
        $a_value = trim ($s[1]);
        return "<a href='${a_value}'>${o_value}</a>";
}

// FIXME: should this be saved as "P-data"?
function execGMarker ($line)
{
        return preg_replace ('/^.+%GSKIP%/', '', preg_replace ('/^(.+)%GPASS%/', '\\1 ', $line));
}

// rackspace usage for a single rack
// (T + W + U) / (height * 3 - A)
function getRSUforRack ($data)
{
        $counter = array ('A' => 0, 'U' => 0, 'T' => 0, 'W' => 0, 'F' => 0);
        for ($unit_no = $data['height']; $unit_no > 0; $unit_no--)
                for ($locidx = 0; $locidx < 3; $locidx++)
                        $counter[$data[$unit_no][$locidx]['state']]++;
        return ($counter['T'] + $counter['W'] + $counter['U']) / ($counter['T'] + $counter['W'] + $counter['U'] + $counter['F']);
}

// Same for row.
function getRSUforRackRow ($rowData)
{
        if (!count ($rowData))
                return 0;
        $counter = array ('A' => 0, 'U' => 0, 'T' => 0, 'W' => 0, 'F' => 0);
        $total_height = 0;
        foreach (array_keys ($rowData) as $rack_id)
        {
                $data = spotEntity ('rack', $rack_id);
                amplifyCell ($data);
                $total_height += $data['height'];
                for ($unit_no = $data['height']; $unit_no > 0; $unit_no--)
                        for ($locidx = 0; $locidx < 3; $locidx++)
                                $counter[$data[$unit_no][$locidx]['state']]++;
        }
        return ($counter['T'] + $counter['W'] + $counter['U']) / ($counter['T'] + $counter['W'] + $counter['U'] + $counter['F']);
}

// Make sure the string is always wrapped with LF characters
function lf_wrap ($str)
{
        $ret = trim ($str, "\r\n");
        if (strlen ($ret))
                $ret .= "\n";
        return $ret;
}

// Adopted from Mantis BTS code.
function string_insert_hrefs ($s)
{
        if (getConfigVar ('DETECT_URLS') != 'yes')
                return $s;
        # Find any URL in a string and replace it by a clickable link
        $s = preg_replace( '/(([[:alpha:]][-+.[:alnum:]]*):\/\/(%[[:digit:]A-Fa-f]{2}|[-_.!~*\';\/?%^\\\\:@&={\|}+$#\(\),\[\][:alnum:]])+)/se',
                "'<a href=\"'.rtrim('\\1','.').'\">\\1</a> [<a href=\"'.rtrim('\\1','.').'\" target=\"_blank\">^</a>]'",
                $s);
        $s = preg_replace( '/\b' . email_regex_simple() . '\b/i',
                '<a href="mailto:\0">\0</a>',
                $s);
        return $s;
}

// Idem.
function email_regex_simple ()
{
        return "(([a-z0-9!#*+\/=?^_{|}~-]+(?:\.[a-z0-9!#*+\/=?^_{|}~-]+)*)" . # recipient
        "\@((?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?))"; # @domain
}

// Parse AUTOPORTS_CONFIG and return a list of generated pairs (port_type, port_name)
// for the requested object_type_id.
function getAutoPorts ($type_id)
{
        $ret = array();
        $typemap = explode (';', str_replace (' ', '', getConfigVar ('AUTOPORTS_CONFIG')));
        foreach ($typemap as $equation)
        {
                $tmp = explode ('=', $equation);
                if (count ($tmp) != 2)
                        continue;
                $objtype_id = $tmp[0];
                if ($objtype_id != $type_id)
                        continue;
                $portlist = $tmp[1];
                foreach (explode ('+', $portlist) as $product)
                {
                        $tmp = explode ('*', $product);
                        if (count ($tmp) != 3)
                                continue;
                        $nports = $tmp[0];
                        $port_type = $tmp[1];
                        $format = $tmp[2];
                        for ($i = 0; $i < $nports; $i++)
                                $ret[] = array ('type' => $port_type, 'name' => @sprintf ($format, $i));
                }
        }
        return $ret;
}

// Use pre-served trace to traverse the tree, then place given node where it belongs.
function pokeNode (&$tree, $trace, $key, $value, $threshold = 0)
{
        // This function needs the trace to be followed FIFO-way. The fastest
        // way to do so is to use array_push() for putting values into the
        // list and array_shift() for getting them out. This exposed up to 11%
        // performance gain compared to other patterns of array_push/array_unshift/
        // array_reverse/array_pop/array_shift conjunction.
        $myid = array_shift ($trace);
        if (!count ($trace)) // reached the target
        {
                if (!$threshold or ($threshold and $tree[$myid]['kidc'] + 1 < $threshold))
                        $tree[$myid]['kids'][$key] = $value;
                // Reset accumulated records once, when the limit is reached, not each time
                // after that.
                if (++$tree[$myid]['kidc'] == $threshold)
                        $tree[$myid]['kids'] = array();
        }
        else // not yet
        {
                $self = __FUNCTION__;
                $self ($tree[$myid]['kids'], $trace, $key, $value, $threshold);
        }
}

// Likewise traverse the tree with the trace and return the final node.
function peekNode ($tree, $trace, $target_id)
{
        $self = __FUNCTION__;
        if (NULL === ($next = array_shift ($trace))) // warm
        {
                foreach ($tree as $node)
                        if (array_key_exists ('id', $node) and $node['id'] == $target_id) // hot
                                return $node;
        }
        else // cold
        {
                foreach ($tree as $node)
                        if (array_key_exists ('id', $node) and $node['id'] == $next) // warmer
                                return $self ($node['kids'], $trace, $target_id);
        }
        // HCF
        return NULL;
}

// Build a tree from the item list and return it. Input and output data is
// indexed by item id (nested items in output are recursively stored in 'kids'
// key, which is in turn indexed by id. Functions, which are ready to handle
// tree collapsion/expansion themselves, may request non-zero threshold value
// for smaller resulting tree.
function treeFromList (&$orig_nodelist, $threshold = 0, $return_main_payload = TRUE)
{
        $tree = array();
        $nodelist = $orig_nodelist;
        // Array equivalent of traceEntity() function.
        $trace = array();
        // set kidc and kids only once
        foreach (array_keys ($nodelist) as $nodeid)
        {
                $nodelist[$nodeid]['kidc'] = 0;
                $nodelist[$nodeid]['kids'] = array();
        }
        do
        {
                $nextpass = FALSE;
                foreach (array_keys ($nodelist) as $nodeid)
                {
                        // When adding a node to the working tree, book another
                        // iteration, because the new item could make a way for
                        // others onto the tree. Also remove any item added from
                        // the input list, so iteration base shrinks.
                        // First check if we can assign directly.
                        if ($nodelist[$nodeid]['parent_id'] == NULL)
                        {
                                $tree[$nodeid] = $nodelist[$nodeid];
                                $trace[$nodeid] = array(); // Trace to root node is empty
                                unset ($nodelist[$nodeid]);
                                $nextpass = TRUE;
                        }
                        // Now look if it fits somewhere on already built tree.
                        elseif (isset ($trace[$nodelist[$nodeid]['parent_id']]))
                        {
                                // Trace to a node is a trace to its parent plus parent id.
                                $trace[$nodeid] = $trace[$nodelist[$nodeid]['parent_id']];
                                $trace[$nodeid][] = $nodelist[$nodeid]['parent_id'];
                                pokeNode ($tree, $trace[$nodeid], $nodeid, $nodelist[$nodeid], $threshold);
                                // path to any other node is made of all parent nodes plus the added node itself
                                unset ($nodelist[$nodeid]);
                                $nextpass = TRUE;
                        }
                }
        }
        while ($nextpass);
        if (!$return_main_payload)
                return $nodelist;
        // update each input node with its backtrace route
        foreach ($trace as $nodeid => $route)
                $orig_nodelist[$nodeid]['trace'] = $route;
        return $tree;
}

// Build a tree from the tag list and return everything _except_ the tree.
// IOW, return taginfo items, which have parent_id set and pointing outside
// of the "normal" tree, which originates from the root.
function getOrphanedTags ()
{
        global $taglist;
        return treeFromList ($taglist, 0, FALSE);
}

function serializeTags ($chain, $baseurl = '')
{
        $comma = '';
        $ret = '';
        foreach ($chain as $taginfo)
        {
                $ret .= $comma .
                        ($baseurl == '' ? '' : "<a href='${baseurl}cft[]=${taginfo['id']}'>") .
                        $taginfo['tag'] .
                        ($baseurl == '' ? '' : '</a>');
                $comma = ', ';
        }
        return $ret;
}

// Return the list of missing implicit tags.
function getImplicitTags ($oldtags)
{
        global $taglist;
        $tmp = array();
        foreach ($oldtags as $taginfo)
                $tmp = array_merge ($tmp, $taglist[$taginfo['id']]['trace']);
        // don't call array_unique here, it is in the function we will call now
        return buildTagChainFromIds ($tmp);
}

// Minimize the chain: exclude all implicit tags and return the result.
// This function makes use of an external cache with a miss/hit ratio
// about 3/7 (ticket:255).
function getExplicitTagsOnly ($chain)
{
        global $taglist, $tagRelCache;
        $ret = array();
        foreach (array_keys ($chain) as $keyA) // check each A
        {
                $tagidA = $chain[$keyA]['id'];
                // do not include A in result, if A is seen on the trace of any B!=A
                foreach (array_keys ($chain) as $keyB)
                {
                        $tagidB = $chain[$keyB]['id'];
                        if ($tagidA == $tagidB)
                                continue;
                        if (!isset ($tagRelCache[$tagidA][$tagidB]))
                                $tagRelCache[$tagidA][$tagidB] = in_array ($tagidA, $taglist[$tagidB]['trace']);
                        if ($tagRelCache[$tagidA][$tagidB] === TRUE) // A is ancestor of B
                                continue 2; // skip this A
                }
                $ret[] = $chain[$keyA];
        }
        return $ret;
}

// Universal autotags generator, a complementing function for loadEntityTags().
// Bypass key isn't strictly typed, but interpreted depending on the realm.
function generateEntityAutoTags ($cell)
{
        $ret = array();
        switch ($cell['realm'])
        {
                case 'rack':
                        $ret[] = array ('tag' => '$rackid_' . $cell['id']);
                        $ret[] = array ('tag' => '$any_rack');
                        break;
                case 'object':
                        $ret[] = array ('tag' => '$id_' . $cell['id']);
                        $ret[] = array ('tag' => '$typeid_' . $cell['objtype_id']);
                        $ret[] = array ('tag' => '$any_object');
                        if (validTagName ('$cn_' . $cell['name'], TRUE))
                                $ret[] = array ('tag' => '$cn_' . $cell['name']);
                        if (!strlen ($cell['rack_id']))
                                $ret[] = array ('tag' => '$unmounted');
                        if (!$cell['nports'])
                                $ret[] = array ('tag' => '$portless');
                        if ($cell['asset_no'] == '')
                                $ret[] = array ('tag' => '$no_asset_tag');
                        if ($cell['runs8021Q'])
                                $ret[] = array ('tag' => '$runs_8021Q');

                        // dictionary attribute autotags '$attr_X_Y'
                        $attrs = getAttrValues($cell['id']);
                        foreach ($attrs as $attr_id => $attr_record)
                                if (isset ($attr_record['key']))
                                        $ret[] = array ('tag' => "\$attr_{$attr_id}_{$attr_record['key']}");
                        break;
                case 'ipv4net':
                        $ret[] = array ('tag' => '$ip4netid_' . $cell['id']);
                        $ret[] = array ('tag' => '$ip4net-' . str_replace ('.', '-', $cell['ip']) . '-' . $cell['mask']);
                        for ($i = 8; $i < 32; $i++)
                        {
                                // these conditions hit 1 to 3 times per each i
                                if ($cell['mask'] >= $i)
                                        $ret[] = array ('tag' => '$masklen_ge_' . $i);
                                if ($cell['mask'] <= $i)
                                        $ret[] = array ('tag' => '$masklen_le_' . $i);
                                if ($cell['mask'] == $i)
                                        $ret[] = array ('tag' => '$masklen_eq_' . $i);
                        }
                        $ret[] = array ('tag' => '$any_ip4net');
                        $ret[] = array ('tag' => '$any_net');
                        break;
                case 'ipv6net':
                        $ret[] = array ('tag' => '$ip6netid_' . $cell['id']);
                        $ret[] = array ('tag' => '$any_ip6net');
                        $ret[] = array ('tag' => '$any_net');
                        break;
                case 'ipv4vs':
                        $ret[] = array ('tag' => '$ipv4vsid_' . $cell['id']);
                        $ret[] = array ('tag' => '$any_ipv4vs');
                        $ret[] = array ('tag' => '$any_vs');
                        break;
                case 'ipv4rspool':
                        $ret[] = array ('tag' => '$ipv4rspid_' . $cell['id']);
                        $ret[] = array ('tag' => '$any_ipv4rsp');
                        $ret[] = array ('tag' => '$any_rsp');
                        break;
                case 'user':
                        // {$username_XXX} autotag is generated always, but {$userid_XXX}
                        // appears only for accounts, which exist in local database.
                        $ret[] = array ('tag' => '$username_' . $cell['user_name']);
                        if (isset ($cell['user_id']))
                                $ret[] = array ('tag' => '$userid_' . $cell['user_id']);
                        break;
                case 'file':
                        $ret[] = array ('tag' => '$fileid_' . $cell['id']);
                        $ret[] = array ('tag' => '$any_file');
                        break;
                default: // HCF!
                        break;
        }
        // {$tagless} doesn't apply to users
        switch ($cell['realm'])
        {
                case 'rack':
                case 'object':
                case 'ipv4net':
                case 'ipv4vs':
                case 'ipv4rspool':
                case 'file':
                        if (!count ($cell['etags']))
                                $ret[] = array ('tag' => '$untagged');
                        break;
                default:
                        break;
        }
        return $ret;
}

// Check, if the given tag is present on the chain (will only work
// for regular tags with tag ID set.
function tagOnChain ($taginfo, $tagchain)
{
        if (!isset ($taginfo['id']))
                return FALSE;
        foreach ($tagchain as $test)
                if ($test['id'] == $taginfo['id'])
                        return TRUE;
        return FALSE;
}

function tagNameOnChain ($tagname, $tagchain)
{
        foreach ($tagchain as $test)
                if ($test['tag'] == $tagname)
                        return TRUE;
        return FALSE;
}

// Return TRUE, if two tags chains differ (order of tags doesn't matter).
// Assume, that neither of the lists contains duplicates.
// FIXME: a faster, than O(x^2) method is possible for this calculation.
function tagChainCmp ($chain1, $chain2)
{
        if (count ($chain1) != count ($chain2))
                return TRUE;
        foreach ($chain1 as $taginfo1)
                if (!tagOnChain ($taginfo1, $chain2))
                        return TRUE;
        return FALSE;
}

function redirectIfNecessary ()
{
        global
                $trigger,
                $pageno,
                $tabno;
        $pmap = array
        (
                'accounts' => 'userlist',
                'rspools' => 'ipv4rsplist',
                'rspool' => 'ipv4rsp',
                'vservices' => 'ipv4vslist',
                'vservice' => 'ipv4vs',
                'objects' => 'depot',
                'objgroup' => 'depot',
        );
        $tmap = array();
        $tmap['objects']['newmulti'] = 'addmore';
        $tmap['objects']['newobj'] = 'addmore';
        $tmap['object']['switchvlans'] = 'livevlans';
        $tmap['object']['slb'] = 'editrspvs';
        $tmap['object']['portfwrd'] = 'nat4';
        $tmap['object']['network'] = 'ipv4';
        if (isset ($pmap[$pageno]))
                redirectUser ($pmap[$pageno], $tabno);
        if (isset ($tmap[$pageno][$tabno]))
                redirectUser ($pageno, $tmap[$pageno][$tabno]);

        if
        (
                ! isset ($_REQUEST['tab']) and
                isset ($_SESSION['RTLT'][$pageno]) and
                getConfigVar ('SHOW_LAST_TAB') == 'yes' and
                permitted ($pageno, $_SESSION['RTLT'][$pageno]['tabname']) and
                time() - $_SESSION['RTLT'][$pageno]['time'] <= TAB_REMEMBER_TIMEOUT
        )
                redirectUser ($pageno, $_SESSION['RTLT'][$pageno]['tabname']);

        // check if we accidentaly got on a dynamic tab that shouldn't be shown for this object
        if
        (
                isset ($trigger[$pageno][$tabno]) and
                !strlen (call_user_func ($trigger[$pageno][$tabno]))
        )
        {
                $_SESSION['RTLT'][$pageno]['dont_remember'] = 1;
                redirectUser ($pageno, 'default');
        }
}

function prepareNavigation()
{
        global
                $pageno,
                $tabno;
        $pageno = (isset ($_REQUEST['page'])) ? $_REQUEST['page'] : 'index';

        if (isset ($_REQUEST['tab']))
                $tabno = $_REQUEST['tab'];
        else
                $tabno = 'default';
}

function fixContext ($target = NULL)
{
        global
                $pageno,
                $auto_tags,
                $expl_tags,
                $impl_tags,
                $target_given_tags,
                $user_given_tags,
                $etype_by_pageno,
                $page;

        if ($target !== NULL)
        {
                $target_given_tags = $target['etags'];
                // Don't reset autochain, because auth procedures could push stuff there in.
                // Another important point is to ignore 'user' realm, so we don't infuse effective
                // context with autotags of the displayed account.
                if ($target['realm'] != 'user')
                        $auto_tags = array_merge ($auto_tags, $target['atags']);
        }
        elseif (array_key_exists ($pageno, $etype_by_pageno))
        {
                // Each page listed in the map above requires one uint argument.
                $target_realm = $etype_by_pageno[$pageno];
                assertUIntArg ($page[$pageno]['bypass']);
                $target_id = $_REQUEST[$page[$pageno]['bypass']];
                $target = spotEntity ($target_realm, $target_id);
                $target_given_tags = $target['etags'];
                if ($target['realm'] != 'user')
                        $auto_tags = array_merge ($auto_tags, $target['atags']);
        }
        // Explicit and implicit chains should be normally empty at this point, so
        // overwrite the contents anyway.
        $expl_tags = mergeTagChains ($user_given_tags, $target_given_tags);
        $impl_tags = getImplicitTags ($expl_tags);
}

// Take a list of user-supplied tag IDs to build a list of valid taginfo
// records indexed by tag IDs (tag chain).
function buildTagChainFromIds ($tagidlist)
{
        global $taglist;
        $ret = array();
        foreach (array_unique ($tagidlist) as $tag_id)
                if (isset ($taglist[$tag_id]))
                        $ret[] = $taglist[$tag_id];
        return $ret;
}

// Process a given tag tree and return only meaningful branches. The resulting
// (sub)tree will have refcnt leaves on every last branch.
function getObjectiveTagTree ($tree, $realm, $preselect)
{
        $self = __FUNCTION__;
        $ret = array();
        foreach ($tree as $taginfo)
        {
                $subsearch = $self ($taginfo['kids'], $realm, $preselect);
                // If the current node addresses something, add it to the result
                // regardless of how many sub-nodes it features.
                if
                (
                        isset ($taginfo['refcnt'][$realm]) or
                        count ($subsearch) > 1 or
                        in_array ($taginfo['id'], $preselect)
                )
                        $ret[] = array
                        (
                                'id' => $taginfo['id'],
                                'tag' => $taginfo['tag'],
                                'parent_id' => $taginfo['parent_id'],
                                'refcnt' => $taginfo['refcnt'],
                                'kids' => $subsearch
                        );
                else
                        $ret = array_merge ($ret, $subsearch);
        }
        return $ret;
}

// Preprocess tag tree to get only tags which can effectively reduce given filter result,
// than passes shrinked tag tree to getObjectiveTagTree and return its result.
// This makes sense only if andor mode is 'and', otherwise function does not modify tree.
// 'Given filter' is a pair of $entity_list(filter result) and $preselect(filter data).
// 'Effectively' means reduce to non-empty result.
function getShrinkedTagTree($entity_list, $realm, $preselect) {
        global $tagtree;
        if ($preselect['andor'] != 'and' || empty($entity_list) && $preselect['is_empty'])
                return getObjectiveTagTree($tagtree, $realm, $preselect['tagidlist']);
        
        $used_tags = array(); //associative, keys - tag ids, values - taginfos
        foreach ($entity_list as $entity)
        {
                foreach ($entity['etags'] as $etag)
                        if (! array_key_exists($etag['id'], $used_tags))
                                $used_tags[$etag['id']] = 1;
                        else
                                $used_tags[$etag['id']]++;
        
                foreach ($entity['itags'] as $itag)
                        if (! array_key_exists($itag['id'], $used_tags))
                                $used_tags[$itag['id']] = 0;
        }
        
        $shrinked_tree = shrinkSubtree($tagtree, $used_tags, $preselect, $realm);
        return getObjectiveTagTree($shrinked_tree, $realm, $preselect['tagidlist']);
}

// deletes item from tag subtree unless it exists in $used_tags and not preselected
function shrinkSubtree($tree, $used_tags, $preselect, $realm) {
        $self = __FUNCTION__;
        
        foreach($tree as $i => &$item) {
                $item['kids'] = $self($item['kids'], $used_tags, $preselect, $realm);
                $item['kidc'] = count($item['kids']);
                if
                (
                        ! array_key_exists($item['id'], $used_tags) && 
                        ! in_array($item['id'], $preselect['tagidlist']) &&
                        ! $item['kidc']
                )
                        unset($tree[$i]);
                else {
                        $item['refcnt'][$realm] = $used_tags[$item['id']];
                        if (! $item['refcnt'][$realm])
                                unset($item['refcnt'][$realm]);
                }
        }
        return $tree;
}

// Get taginfo record by tag name, return NULL, if record doesn't exist.
function getTagByName ($target_name)
{
        global $taglist;
        foreach ($taglist as $taginfo)
                if ($taginfo['tag'] == $target_name)
                        return $taginfo;
        return NULL;
}

// Merge two chains, filtering dupes out. Return the resulting superset.
function mergeTagChains ($chainA, $chainB)
{
        // $ret = $chainA;
        // Reindex by tag id in any case.
        $ret = array();
        foreach ($chainA as $tag)
                $ret[$tag['id']] = $tag;
        foreach ($chainB as $tag)
                if (!isset ($ret[$tag['id']]))
                        $ret[$tag['id']] = $tag;
        return $ret;
}

function getCellFilter ()
{
        global $sic;
        global $pageno;
        $staticFilter = getConfigVar ('STATIC_FILTER');
        if (isset ($_REQUEST['tagfilter']) and is_array ($_REQUEST['tagfilter']))
        {
                $_REQUEST['cft'] = $_REQUEST['tagfilter'];
                unset ($_REQUEST['tagfilter']);
        }
        $andor_used = FALSE;
        //if the page is submitted we get an andor value so we know they are trying to start a new filter or clearing the existing one.
        if(isset($_REQUEST['andor']))
        {
                $andor_used = TRUE;
                unset($_SESSION[$pageno]);
        }
        if (isset ($_SESSION[$pageno]['tagfilter']) and is_array ($_SESSION[$pageno]['tagfilter']) and !(isset($_REQUEST['cft'])) and $staticFilter == 'yes')
        {
                $_REQUEST['cft'] = $_SESSION[$pageno]['tagfilter'];
        }
        if (isset ($_SESSION[$pageno]['cfe']) and !(isset($sic['cfe'])) and $staticFilter == 'yes')
        {
                $sic['cfe'] = $_SESSION[$pageno]['cfe'];
        }
        if (isset ($_SESSION[$pageno]['andor']) and !(isset($_REQUEST['andor'])) and $staticFilter == 'yes')
        {
                $_REQUEST['andor'] = $_SESSION[$pageno]['andor'];
        }


        $ret = array
        (
                'tagidlist' => array(),
                'tnamelist' => array(),
                'pnamelist' => array(),
                'andor' => '',
                'text' => '',
                'extratext' => '',
                'expression' => array(),
                'urlextra' => '', // Just put text here and let makeHref call urlencode().
                'is_empty' => TRUE,
        );
        switch (TRUE)
        {
        case (!isset ($_REQUEST['andor'])):
                $andor2 = getConfigVar ('FILTER_DEFAULT_ANDOR');
                break;
        case ($_REQUEST['andor'] == 'and'):
        case ($_REQUEST['andor'] == 'or'):
                $_SESSION[$pageno]['andor'] = $_REQUEST['andor'];
                $ret['andor'] = $andor2 = $_REQUEST['andor'];
                break;
        default:
                showWarning ('Invalid and/or switch value in submitted form', __FUNCTION__);
                return NULL;
        }
        $andor1 = '';
        // Both tags and predicates, which don't exist, should be
        // handled somehow. Discard them silently for now.
        if (isset ($_REQUEST['cft']) and is_array ($_REQUEST['cft']))
        {
                $_SESSION[$pageno]['tagfilter'] = $_REQUEST['cft'];
                global $taglist;
                foreach ($_REQUEST['cft'] as $req_id)
                        if (isset ($taglist[$req_id]))
                        {
                                $ret['tagidlist'][] = $req_id;
                                $ret['tnamelist'][] = $taglist[$req_id]['tag'];
                                $andor_used = $andor_used || (trim($andor1) != '');
                                $ret['text'] .= $andor1 . '{' . $taglist[$req_id]['tag'] . '}';
                                $andor1 = ' ' . $andor2 . ' ';
                                $ret['urlextra'] .= '&cft[]=' . $req_id;
                        }
        }
        if (isset ($_REQUEST['cfp']) and is_array ($_REQUEST['cfp']))
        {
                global $pTable;
                foreach ($_REQUEST['cfp'] as $req_name)
                        if (isset ($pTable[$req_name]))
                        {
                                $ret['pnamelist'][] = $req_name;
                                $andor_used = $andor_used || (trim($andor1) != '');
                                $ret['text'] .= $andor1 . '[' . $req_name . ']';
                                $andor1 = ' ' . $andor2 . ' ';
                                $ret['urlextra'] .= '&cfp[]=' . $req_name;
                        }
        }
        // Extra text comes from TEXTAREA and is easily screwed by standard escaping function.
        if (isset ($sic['cfe']))
        {
                $_SESSION[$pageno]['cfe'] = $sic['cfe'];
                // Only consider extra text, when it is a correct RackCode expression.
                $parse = spotPayload ($sic['cfe'], 'SYNT_EXPR');
                if ($parse['result'] == 'ACK')
                {
                        $ret['extratext'] = trim ($sic['cfe']);
                        $ret['urlextra'] .= '&cfe=' . $ret['extratext'];
                }
        }
        $finaltext = array();
        if (strlen ($ret['text']))
                $finaltext[] = '(' . $ret['text'] . ')';
        if (strlen ($ret['extratext']))
                $finaltext[] = '(' . $ret['extratext'] . ')';
        $andor_used = $andor_used || (count($finaltext) > 1);
        $finaltext = implode (' ' . $andor2 . ' ', $finaltext);
        if (strlen ($finaltext))
        {
                $ret['is_empty'] = FALSE;
                $parse = spotPayload ($finaltext, 'SYNT_EXPR');
                $ret['expression'] = $parse['result'] == 'ACK' ? $parse['load'] : NULL;
                // It's not quite fair enough to put the blame of the whole text onto
                // non-empty "extra" portion of it, but it's the only user-generated portion
                // of it, thus the most probable cause of parse error.
                if (strlen ($ret['extratext']))
                        $ret['extraclass'] = $parse['result'] == 'ACK' ? 'validation-success' : 'validation-error';
        }
        if (! $andor_used)
                $ret['andor'] = getConfigVar ('FILTER_DEFAULT_ANDOR');
        else
                $ret['urlextra'] .= '&andor=' . $ret['andor'];
        return $ret;
}

// Return an empty message log.
function emptyLog ()
{
        return array
        (
                'v' => 2,
                'm' => array()
        );
}

// Return a message log consisting of only one message.
function oneLiner ($code, $args = array())
{
        $ret = emptyLog();
        $ret['m'][] = count ($args) ? array ('c' => $code, 'a' => $args) : array ('c' => $code);
        return $ret;
}

// Merge message payload from two message logs given and return the result.
function mergeLogs ($log1, $log2)
{
        $ret = emptyLog();
        $ret['m'] = array_merge ($log1['m'], $log2['m']);
        return $ret;
}

function validTagName ($s, $allow_autotag = FALSE)
{
        if (1 == preg_match (TAGNAME_REGEXP, $s))
                return TRUE;
        if ($allow_autotag and 1 == preg_match (AUTOTAGNAME_REGEXP, $s))
                return TRUE;
        return FALSE;
}

function redirectUser ($p, $t)
{
        global $page;
        $l = "index.php?page=${p}&tab=${t}";
        if (isset ($page[$p]['bypass']) and isset ($_REQUEST[$page[$p]['bypass']]))
                $l .= '&' . $page[$p]['bypass'] . '=' . $_REQUEST[$page[$p]['bypass']];
        if (isset ($page[$p]['bypass_tabs']))
                foreach ($page[$p]['bypass_tabs'] as $param_name)
                        if (isset ($_REQUEST[$param_name]))
                                $l .= '&' . urlencode ($param_name) . '=' . urlencode ($_REQUEST[$param_name]);
        header ("Location: " . $l);
        die;
}

function getRackCodeStats ()
{
        global $rackCode;
        $defc = $grantc = $modc = 0;
        foreach ($rackCode as $s)
                switch ($s['type'])
                {
                        case 'SYNT_DEFINITION':
                                $defc++;
                                break;
                        case 'SYNT_GRANT':
                                $grantc++;
                                break;
                        case 'SYNT_CTXMOD':
                                $modc++;
                                break;
                        default:
                                break;
                }
        $ret = array
        (
                'Definition sentences' => $defc,
                'Grant sentences' => $grantc,
                'Context mod sentences' => $modc
        );
        return $ret;
}

function getRackImageWidth ()
{
        global $rtwidth;
        return 3 + $rtwidth[0] + $rtwidth[1] + $rtwidth[2] + 3;
}

function getRackImageHeight ($units)
{
        return 3 + 3 + $units * 2;
}

// Perform substitutions and return resulting string
// used solely by buildLVSConfig()
function apply_macros ($macros, $subject, &$error_macro_stat)
{
        // clear all text before last %RESET% macro
        $reset_keyword = '%RESET%';
        $reset_position = mb_strpos($subject, $reset_keyword, 0);
        if ($reset_position === FALSE)
                $ret = $subject;
        else
                $ret = trim
                (
                        mb_substr($subject, $reset_position + mb_strlen($reset_keyword)),
                        "\n\r"
                );

        foreach ($macros as $search => $replace)
        {
                if (empty($replace))
                {
                        $replace = "<span class=\"msg_error\">$search</span>";
                        $count = 0;
                        $ret = str_replace ($search, $replace, $ret, $count);
                        if ($count)
                        {
                                if (array_key_exists($search, $error_macro_stat))
                                        $error_macro_stat[$search] += $count;
                                else
                                        $error_macro_stat[$search] = $count;
                        }
                }
                else
                        $ret = str_replace ($search, $replace, $ret);
        }
        return $ret;
}

// throws RTBuildLVSConfigError exception if undefined macros found
function buildLVSConfig ($object_id)
{
        $oInfo = spotEntity ('object', $object_id);
        $defaults = getSLBDefaults (TRUE);
        $lbconfig = getSLBConfig ($object_id);
        if ($lbconfig === NULL)
        {
                showWarning ('getSLBConfig() failed', __FUNCTION__);
                return;
        }
        $newconfig = "#\n#\n# This configuration has been generated automatically by RackTables\n";
        $newconfig .= "# for object_id == ${object_id}\n# object name: ${oInfo['name']}\n#\n#\n\n\n";
        
        $error_stat = array();
        foreach ($lbconfig as $vs_id => $vsinfo)
        {
                $newconfig .=  "########################################################\n" .
                        "# VS (id == ${vs_id}): " . (!strlen ($vsinfo['vs_name']) ? 'NO NAME' : $vsinfo['vs_name']) . "\n" .
                        "# RS pool (id == ${vsinfo['pool_id']}): " . (!strlen ($vsinfo['pool_name']) ? 'ANONYMOUS' : $vsinfo['pool_name']) . "\n" .
                        "########################################################\n";
                # The order of inheritance is: VS -> LB -> pool [ -> RS ]
                $macros = array
                (
                        '%VIP%' => $vsinfo['vip'],
                        '%VPORT%' => $vsinfo['vport'],
                        '%PROTO%' => $vsinfo['proto'],
                        '%VNAME%' =>  $vsinfo['vs_name'],
                        '%RSPOOLNAME%' => $vsinfo['pool_name'],
                        '%PRIO%' => $vsinfo['prio']
                );
                $newconfig .=  "virtual_server ${vsinfo['vip']} ${vsinfo['vport']} {\n";
                $newconfig .=  "\tprotocol ${vsinfo['proto']}\n";
                $newconfig .= lf_wrap (apply_macros
                (
                        $macros,
                        lf_wrap ($defaults['vs']) .
                        lf_wrap ($vsinfo['vs_vsconfig']) .
                        lf_wrap ($vsinfo['lb_vsconfig']) .
                        lf_wrap ($vsinfo['pool_vsconfig']),
                        $error_stat
                ));
                foreach ($vsinfo['rslist'] as $rs)
                {
                        if (!strlen ($rs['rsport']))
                                $rs['rsport'] = $vsinfo['vport'];
                        $macros['%RSIP%'] = $rs['rsip'];
                        $macros['%RSPORT%'] = $rs['rsport'];
                        $newconfig .=  "\treal_server ${rs['rsip']} ${rs['rsport']} {\n";
                        $newconfig .= lf_wrap (apply_macros
                        (
                                $macros,
                                lf_wrap ($defaults['rs']) .
                                lf_wrap ($vsinfo['vs_rsconfig']) .
                                lf_wrap ($vsinfo['lb_rsconfig']) .
                                lf_wrap ($vsinfo['pool_rsconfig']) .
                                lf_wrap ($rs['rs_rsconfig']),
                                $error_stat
                        ));
                        $newconfig .=  "\t}\n";
                }
                $newconfig .=  "}\n\n\n";
        }
        if (! empty($error_stat))
        {
                $error_messages = array();
                foreach ($error_stat as $macro => $count)
                        $error_messages[] = "Error: macro $macro can not be empty ($count occurences)";
                throw new RTBuildLVSConfigError($error_messages, $newconfig, $object_id);
        }
        
        // FIXME: deal somehow with Mac-styled text, the below replacement will screw it up
        return dos2unix ($newconfig);
}

// Indicate occupation state of each IP address: none, ordinary or problematic.
function markupIPAddrList (&$addrlist)
{
        foreach (array_keys ($addrlist) as $ip_bin)
        {
                $refc = array
                (
                        'shared' => 0,  // virtual
                        'virtual' => 0, // loopback
                        'regular' => 0, // connected host
                        'router' => 0   // connected gateway
                );
                foreach ($addrlist[$ip_bin]['allocs'] as $a)
                        $refc[$a['type']]++;
                $nvirtloopback = ($refc['shared'] + $refc['virtual'] > 0) ? 1 : 0; // modulus of virtual + shared
                $nreserved = ($addrlist[$ip_bin]['reserved'] == 'yes') ? 1 : 0; // only one reservation is possible ever
                $nrealms = $nreserved + $nvirtloopback + $refc['regular'] + $refc['router']; // latter two are connected and router allocations
                
                if ($nrealms == 1)
                        $addrlist[$ip_bin]['class'] = 'trbusy';
                elseif ($nrealms > 1)
                        $addrlist[$ip_bin]['class'] = 'trerror';
                else
                        $addrlist[$ip_bin]['class'] = '';
        }
}

// Scan the given address list (returned by scanIPv4Space/scanIPv6Space) and return a list of all routers found.
function findRouters ($addrlist)
{
        $ret = array();
        foreach ($addrlist as $addr)
                foreach ($addr['allocs'] as $alloc)
                        if ($alloc['type'] == 'router')
                                $ret[] = array
                                (
                                        'id' => $alloc['object_id'],
                                        'iface' => $alloc['name'],
                                        'dname' => $alloc['object_name'],
                                        'addr' => $addr['ip']
                                );
        return $ret;
}

// Assist in tag chain sorting.
function taginfoCmp ($tagA, $tagB)
{
        return $tagA['ci'] - $tagB['ci'];
}

// Compare networks. When sorting a tree, the records on the list will have
// distinct base IP addresses.
// "The comparison function must return an integer less than, equal to, or greater
// than zero if the first argument is considered to be respectively less than,
// equal to, or greater than the second." (c) PHP manual
function IPv4NetworkCmp ($netA, $netB)
{
        // On 64-bit systems this function can be reduced to just this:
        if (PHP_INT_SIZE == 8)
                return $netA['ip_bin'] - $netB['ip_bin'];
        // There's a problem just substracting one u32 integer from another,
        // because the result may happen big enough to become a negative i32
        // integer itself (PHP tries to cast everything it sees to signed int)
        // The comparison below must treat positive and negative values of both
        // arguments.
        // Equal values give instant decision regardless of their [equal] sign.
        if ($netA['ip_bin'] == $netB['ip_bin'])
                return 0;
        // Same-signed values compete arithmetically within one of i32 contiguous ranges:
        // 0x00000001~0x7fffffff 1~2147483647
        // 0 doesn't have any sign, and network 0.0.0.0 isn't allowed
        // 0x80000000~0xffffffff -2147483648~-1
        $signA = $netA['ip_bin'] / abs ($netA['ip_bin']);
        $signB = $netB['ip_bin'] / abs ($netB['ip_bin']);
        if ($signA == $signB)
        {
                if ($netA['ip_bin'] > $netB['ip_bin'])
                        return 1;
                else
                        return -1;
        }
        else // With only one of two values being negative, it... wins!
        {
                if ($netA['ip_bin'] < $netB['ip_bin'])
                        return 1;
                else
                        return -1;
        }
}

function IPv6NetworkCmp ($netA, $netB)
{
        return strcmp ($netA['ip_bin'], $netB['ip_bin']);
}

// Modify the given tag tree so, that each level's items are sorted alphabetically.
function sortTree (&$tree, $sortfunc = '')
{
        if (!strlen ($sortfunc))
                return;
        $self = __FUNCTION__;
        usort ($tree, $sortfunc);
        // Don't make a mistake of directly iterating over the items of current level, because this way
        // the sorting will be performed on a _copy_ if each item, not the item itself.
        foreach (array_keys ($tree) as $tagid)
                $self ($tree[$tagid]['kids'], $sortfunc);
}

function iptree_fill (&$netdata)
{
        if (!isset ($netdata['kids']) or !count ($netdata['kids']))
                return;
        // If we really have nested prefixes, they must fit into the tree.
        $worktree = array
        (
                'ip_bin' => $netdata['ip_bin'],
                'mask' => $netdata['mask']
        );
        foreach ($netdata['kids'] as $pfx)
                iptree_embed ($worktree, $pfx);
        $netdata['kids'] = iptree_construct ($worktree);
        $netdata['kidc'] = count ($netdata['kids']);
}

function ipv6tree_fill (&$netdata)
{
        if (!isset ($netdata['kids']) or !count ($netdata['kids']))
                return;
        // If we really have nested prefixes, they must fit into the tree.
        $worktree = array
        (
                'ip_bin' => $netdata['ip_bin'],
                'mask' => $netdata['mask']
        );
        foreach ($netdata['kids'] as $pfx)
                ipv6tree_embed ($worktree, $pfx);
        $netdata['kids'] = ipv6tree_construct ($worktree);
        $netdata['kidc'] = count ($netdata['kids']);
}

function iptree_construct ($node)
{
        $self = __FUNCTION__;

        if (!isset ($node['right']))
        {
                if (!isset ($node['ip']))
                {
                        $node['ip'] = long2ip ($node['ip_bin']);
                        $node['kids'] = array();
                        $node['kidc'] = 0;
                        $node['name'] = '';
                }
                return array ($node);
        }
        else
                return array_merge ($self ($node['left']), $self ($node['right']));
}

function ipv6tree_construct ($node)
{
        $self = __FUNCTION__;

        if (!isset ($node['right']))
        {
                if (!isset ($node['ip']))
                {
                        $node['ip'] = $node['ip_bin']->format();
                        $node['kids'] = array();
                        $node['kidc'] = 0;
                        $node['name'] = '';
                }
                return array ($node);
        }
        else
                return array_merge ($self ($node['left']), $self ($node['right']));
}

function iptree_embed (&$node, $pfx)
{
        $self = __FUNCTION__;

        // hit?
        if ($node['ip_bin'] == $pfx['ip_bin'] and $node['mask'] == $pfx['mask'])
        {
                $node = $pfx;
                return;
        }
        if ($node['mask'] == $pfx['mask'])
                throw new RackTablesError ('the recurring loop lost control', RackTablesError::INTERNAL);

        // split?
        if (!isset ($node['right']))
        {
                // Fill in db_first/db_last to make it possible to run scanIPv4Space() on the node.
                $node['left']['mask'] = $node['mask'] + 1;
                $node['left']['ip_bin'] = $node['ip_bin'];
                $node['left']['db_first'] = sprintf ('%u', $node['left']['ip_bin']);
                $node['left']['db_last'] = sprintf ('%u', $node['left']['ip_bin'] | binInvMaskFromDec ($node['left']['mask']));

                $node['right']['mask'] = $node['mask'] + 1;
                $node['right']['ip_bin'] = $node['ip_bin'] + binInvMaskFromDec ($node['mask'] + 1) + 1;
                $node['right']['db_first'] = sprintf ('%u', $node['right']['ip_bin']);
                $node['right']['db_last'] = sprintf ('%u', $node['right']['ip_bin'] | binInvMaskFromDec ($node['right']['mask']));
        }

        // repeat!
        if (($node['left']['ip_bin'] & binMaskFromDec ($node['left']['mask'])) == ($pfx['ip_bin'] & binMaskFromDec ($node['left']['mask'])))
                $self ($node['left'], $pfx);
        elseif (($node['right']['ip_bin'] & binMaskFromDec ($node['right']['mask'])) == ($pfx['ip_bin'] & binMaskFromDec ($node['left']['mask'])))
                $self ($node['right'], $pfx);
        else
                throw new RackTablesError ('cannot decide between left and right', RackTablesError::INTERNAL);
}

function ipv6tree_embed (&$node, $pfx)
{
        $self = __FUNCTION__;

        // hit?
        if ($node['ip_bin'] == $pfx['ip_bin'] and $node['mask'] == $pfx['mask'])
        {
                $node = $pfx;
                return;
        }
        if ($node['mask'] == $pfx['mask'])
                throw new RackTablesError ('the recurring loop lost control', RackTablesError::INTERNAL);

        // split?
        if (!isset ($node['right']))
        {
                $node['left']['mask'] = $node['mask'] + 1;
                $node['left']['ip_bin'] = $node['ip_bin'];
                $node['left']['db_first'] = $node['ip_bin']->get_first_subnet_address ($node['mask'] + 1);
                $node['left']['db_last'] = $node['ip_bin']->get_last_subnet_address ($node['mask'] + 1);

                $node['right']['mask'] = $node['mask'] + 1;
                $node['right']['ip_bin'] = $node['ip_bin']->get_last_subnet_address ($node['mask'] + 1)->next();
                $node['right']['db_first'] = $node['right']['ip_bin'];
                $node['right']['db_last'] = $node['right']['ip_bin']->get_last_subnet_address ($node['mask'] + 1);
        }

        // repeat!
        if ($node['left']['db_first'] == $pfx['ip_bin']->get_first_subnet_address ($node['left']['mask']))
                $self ($node['left'], $pfx);
        elseif ($node['right']['db_first'] == $pfx['ip_bin']->get_first_subnet_address ($node['left']['mask']))
                $self ($node['right'], $pfx);
        else
                throw new RackTablesError ('cannot decide between left and right', RackTablesError::INTERNAL);
}

function treeApplyFunc (&$tree, $func = '', $stopfunc = '')
{
        if (!strlen ($func))
                return;
        $self = __FUNCTION__;
        foreach (array_keys ($tree) as $key)
        {
                $func ($tree[$key]);
                if (strlen ($stopfunc) and $stopfunc ($tree[$key]))
                        continue;
                $self ($tree[$key]['kids'], $func);
        }
}

function loadIPv4AddrList (&$netinfo)
{
        loadOwnIPv4Addresses ($netinfo);
        markupIPAddrList ($netinfo['addrlist']);
}

function countOwnIPv4Addresses (&$node)
{
        $node['addrt'] = 0;
        if (empty ($node['kids']))
                $node['addrt'] = binInvMaskFromDec ($node['mask']) + 1;
        else
                foreach ($node['kids'] as $nested)
                        if (!isset ($nested['id'])) // spare
                                $node['addrt'] += binInvMaskFromDec ($nested['mask']) + 1;
}

function nodeIsCollapsed ($node)
{
        return $node['symbol'] == 'node-collapsed';
}

// implies countOwnIPv4Addresses
function loadOwnIPv4Addresses (&$node)
{
        $toscan = array();
        $node['addrt'] = 0;
        if (!isset ($node['kids']) or !count ($node['kids']))
        {
                $toscan[] = array ('i32_first' => $node['db_first'], 'i32_last' => $node['db_last']);
                $node['addrt'] = $node['db_last'] - $node['db_first'] + 1;
        }
        else
        {
                $node['addrt'] = 0;
                foreach ($node['kids'] as $nested)
                        if (!isset ($nested['id'])) // spare
                        {
                                $toscan[] = array ('i32_first' => $nested['db_first'], 'i32_last' => $nested['db_last']);
                                $node['addrt'] += $node['db_last'] - $node['db_first'] + 1;
                        }
        }
        $node['addrlist'] = scanIPv4Space ($toscan);
        $node['addrc'] = count ($node['addrlist']);
}

function loadIPv6AddrList (&$netinfo)
{
        loadOwnIPv6Addresses ($netinfo);
        markupIPAddrList ($netinfo['addrlist']);
}

function loadOwnIPv6Addresses (&$node)
{
        $toscan = array();
        $node['addrt'] = 0;
        if (empty ($node['kids']))
                $toscan[] = array ('first' => $node['ip_bin'], 'last' => $node['ip_bin']->get_last_subnet_address ($node['mask']));
        else
                foreach ($node['kids'] as $nested)
                        if (!isset ($nested['id'])) // spare
                                $toscan[] = array ('first' => $nested['ip_bin'], 'last' => $nested['ip_bin']->get_last_subnet_address ($nested['mask']));
        $node['addrlist'] = scanIPv6Space ($toscan);
        $node['addrc'] = count ($node['addrlist']);
}

function prepareIPv4Tree ($netlist, $expanded_id = 0)
{
        // treeFromList() requires parent_id to be correct for an item to get onto the tree,
        // so perform necessary pre-processing to make orphans belong to root. This trick
        // was earlier performed by getIPv4NetworkList().
        $netids = array_keys ($netlist);
        foreach ($netids as $cid)
                if (!in_array ($netlist[$cid]['parent_id'], $netids))
                        $netlist[$cid]['parent_id'] = NULL;
        $tree = treeFromList ($netlist); // medium call
        sortTree ($tree, 'IPv4NetworkCmp');
        // complement the tree before markup to make the spare networks have "symbol" set
        treeApplyFunc ($tree, 'iptree_fill');
        iptree_markup_collapsion ($tree, getConfigVar ('TREE_THRESHOLD'), $expanded_id);
        // count addresses after the markup to skip computation for hidden tree nodes
        treeApplyFunc ($tree, 'countOwnIPv4Addresses', 'nodeIsCollapsed');
        return $tree;
}

function prepareIPv6Tree ($netlist, $expanded_id = 0)
{
        // treeFromList() requires parent_id to be correct for an item to get onto the tree,
        // so perform necessary pre-processing to make orphans belong to root. This trick
        // was earlier performed by getIPv4NetworkList().
        $netids = array_keys ($netlist);
        foreach ($netids as $cid)
                if (!in_array ($netlist[$cid]['parent_id'], $netids))
                        $netlist[$cid]['parent_id'] = NULL;
        $tree = treeFromList ($netlist); // medium call
        sortTree ($tree, 'IPv6NetworkCmp');
        // complement the tree before markup to make the spare networks have "symbol" set
        treeApplyFunc ($tree, 'ipv6tree_fill');
        iptree_markup_collapsion ($tree, getConfigVar ('TREE_THRESHOLD'), $expanded_id);
        return $tree;
}

// Check all items of the tree recursively, until the requested target id is
// found. Mark all items leading to this item as "expanded", collapsing all
// the rest, which exceed the given threshold (if the threshold is given).
function iptree_markup_collapsion (&$tree, $threshold = 1024, $target = 0)
{
        $self = __FUNCTION__;
        $ret = FALSE;
        foreach (array_keys ($tree) as $key)
        {
                $here = ($target === 'ALL' or ($target > 0 and isset ($tree[$key]['id']) and $tree[$key]['id'] == $target));
                $below = $self ($tree[$key]['kids'], $threshold, $target);
                if (!$tree[$key]['kidc']) // terminal node
                        $tree[$key]['symbol'] = 'spacer';
                elseif ($tree[$key]['kidc'] < $threshold)
                        $tree[$key]['symbol'] = 'node-expanded-static';
                elseif ($here or $below)
                        $tree[$key]['symbol'] = 'node-expanded';
                else
                        $tree[$key]['symbol'] = 'node-collapsed';
                $ret = ($ret or $here or $below); // parentheses are necessary for this to be computed correctly
        }
        return $ret;
}

// Convert entity name to human-readable value
function formatEntityName ($name) {
        switch ($name)
        {
                case 'ipv4net':
                        return 'IPv4 Network';
                case 'ipv4rspool':
                        return 'IPv4 RS Pool';
                case 'ipv4vs':
                        return 'IPv4 Virtual Service';
                case 'object':
                        return 'Object';
                case 'rack':
                        return 'Rack';
                case 'user':
                        return 'User';
        }
        return 'invalid';
}

// Take a MySQL or other generic timestamp and make it prettier
function formatTimestamp ($timestamp) {
        return date('n/j/y g:iA', strtotime($timestamp));
}

// Display hrefs for all of a file's parents. If scissors are requested,
// prepend cutting button to each of them.
function serializeFileLinks ($links, $scissors = FALSE)
{
        $comma = '';
        $ret = '';
        foreach ($links as $link_id => $li)
        {
                switch ($li['entity_type'])
                {
                        case 'ipv4net':
                                $params = "page=ipv4net&id=";
                                break;
                        case 'ipv4rspool':
                                $params = "page=ipv4rspool&pool_id=";
                                break;
                        case 'ipv4vs':
                                $params = "page=ipv4vs&vs_id=";
                                break;
                        case 'object':
                                $params = "page=object&object_id=";
                                break;
                        case 'rack':
                                $params = "page=rack&rack_id=";
                                break;
                        case 'user':
                                $params = "page=user&user_id=";
                                break;
                }
                $ret .= $comma;
                if ($scissors)
                {
                        $ret .= "<a href='" . makeHrefProcess(array('op'=>'unlinkFile', 'link_id'=>$link_id)) . "'";
                        $ret .= getImageHREF ('cut') . '</a> ';
                }
                $ret .= sprintf("<a href='index.php?%s%s'>%s</a>", $params, $li['entity_id'], $li['name']);
                $comma = '<br>';
        }
        return $ret;
}

// Convert filesize to appropriate unit and make it human-readable
function formatFileSize ($bytes) {
        // bytes
        if($bytes < 1024) // bytes
                return "${bytes} bytes";

        // kilobytes
        if ($bytes < 1024000)
                return sprintf ("%.1fk", round (($bytes / 1024), 1));
        
        // megabytes
        return sprintf ("%.1f MB", round (($bytes / 1024000), 1));
}

// Reverse of formatFileSize, it converts human-readable value to bytes
function convertToBytes ($value) {
        $value = trim($value);
        $last = strtolower($value[strlen($value)-1]);
        switch ($last) 
        {
                case 'g':
                        $value *= 1024;
                case 'm':
                        $value *= 1024;
                case 'k':
                        $value *= 1024;
        }

        return $value;
}

function ip_quad2long ($ip)
{
      return sprintf("%u", ip2long($ip));
}

function ip_long2quad ($quad)
{
      return long2ip($quad);
}

function mkA ($text, $nextpage, $bypass = NULL, $nexttab = NULL)
{
        global $page, $tab;
        if (!mb_strlen ($text))
                throw new InvalidArgException ('text', $text);
        if (!array_key_exists ($nextpage, $page))
                throw new InvalidArgException ('nextpage', $nextpage);
        $args = array ('page' => $nextpage);
        if ($nexttab !== NULL)
        {
                if (!array_key_exists ($nexttab, $tab[$nextpage]))
                        throw new InvalidArgException ('nexttab', $nexttab);
                $args['tab'] = $nexttab;
        }
        if (array_key_exists ('bypass', $page[$nextpage]))
        {
                if ($bypass === NULL)
                        throw new InvalidArgException ('bypass', $bypass);
                $args[$page[$nextpage]['bypass']] = $bypass;
        }
        return '<a href="' . makeHref ($args) . '">' . $text . '</a>';
}

function makeHref($params = array())
{
        $ret = 'index.php?';
        $first = true;
        foreach($params as $key=>$value)
        {
                if (!$first)
                        $ret.='&';
                $ret .= urlencode($key).'='.urlencode($value);
                $first = false;
        }
        return $ret;
}

function makeHrefProcess($params = array())
{
        global $pageno, $tabno;
        $ret = 'process.php?';
        $first = true;
        if (!isset($params['page']))
                $params['page'] = $pageno;
        if (!isset($params['tab']))
                $params['tab'] = $tabno;
        foreach($params as $key=>$value)
        {
                if (!$first)
                        $ret.='&';
                $ret .= urlencode($key).'='.urlencode($value);
                $first = false;
        }
        return $ret;
}

function makeHrefForHelper ($helper_name, $params = array())
{
        $ret = 'popup.php?helper=' . $helper_name;
        foreach($params as $key=>$value)
                $ret .= '&'.urlencode($key).'='.urlencode($value);
        return $ret;
}

// Process the given list of records to build data suitable for printNiftySelect()
// (like it was formerly executed by printSelect()). Screen out vendors according
// to VENDOR_SIEVE, if object type ID is provided. However, the OPTGROUP with already
// selected OPTION is protected from being screened.
function cookOptgroups ($recordList, $object_type_id = 0, $existing_value = 0)
{
        $ret = array();
        // Always keep "other" OPTGROUP at the SELECT bottom.
        $therest = array();
        foreach ($recordList as $dict_key => $dict_value)
                if (strpos ($dict_value, '%GSKIP%') !== FALSE)
                {
                        $tmp = explode ('%GSKIP%', $dict_value, 2);
                        $ret[$tmp[0]][$dict_key] = $tmp[1];
                }
                elseif (strpos ($dict_value, '%GPASS%') !== FALSE)
                {
                        $tmp = explode ('%GPASS%', $dict_value, 2);
                        $ret[$tmp[0]][$dict_key] = $tmp[1];
                }
                else
                        $therest[$dict_key] = $dict_value;
        if ($object_type_id != 0)
        {
                $screenlist = array();
                foreach (explode (';', getConfigVar ('VENDOR_SIEVE')) as $sieve)
                        if (preg_match ("/^([^@]+)(@${object_type_id})?\$/", trim ($sieve), $regs)){
                                $screenlist[] = $regs[1];
                        }
                foreach (array_keys ($ret) as $vendor)
                        if (in_array ($vendor, $screenlist))
                        {
                                $ok_to_screen = TRUE;
                                if ($existing_value)
                                        foreach (array_keys ($ret[$vendor]) as $recordkey)
                                                if ($recordkey == $existing_value)
                                                {
                                                        $ok_to_screen = FALSE;
                                                        break;
                                                }
                                if ($ok_to_screen)
                                        unset ($ret[$vendor]);
                        }
        }
        $ret['other'] = $therest;
        return $ret;
}

function dos2unix ($text)
{
        return str_replace ("\r\n", "\n", $text);
}

function unix2dos ($text)
{
        return str_replace ("\n", "\r\n", $text);
}

function buildPredicateTable ($parsetree)
{
        $ret = array();
        foreach ($parsetree as $sentence)
                if ($sentence['type'] == 'SYNT_DEFINITION')
                        $ret[$sentence['term']] = $sentence['definition'];
        // Now we have predicate table filled in with the latest definitions of each
        // particular predicate met. This isn't as chik, as on-the-fly predicate
        // overloading during allow/deny scan, but quite sufficient for this task.
        return $ret;
}

// Take a list of records and filter against given RackCode expression. Return
// the original list intact, if there was no filter requested, but return an
// empty list, if there was an error.
function filterCellList ($list_in, $expression = array())
{
        if ($expression === NULL)
                return array();
        if (!count ($expression))
                return $list_in;
        $list_out = array();
        foreach ($list_in as $item_key => $item_value)
                if (TRUE === judgeCell ($item_value, $expression))
                        $list_out[$item_key] = $item_value;
        return $list_out;
}

function eval_expression ($expr, $tagchain, $ptable, $silent = FALSE)
{
        $self = __FUNCTION__;
        switch ($expr['type'])
        {
                // Return true, if given tag is present on the tag chain.
                case 'LEX_TAG':
                case 'LEX_AUTOTAG':
                        foreach ($tagchain as $tagInfo)
                                if ($expr['load'] == $tagInfo['tag'])
                                        return TRUE;
                        return FALSE;
                case 'LEX_PREDICATE': // Find given predicate in the symbol table and evaluate it.
                        $pname = $expr['load'];
                        if (!isset ($ptable[$pname]))
                        {
                                if (!$silent)
                                        showWarning ("Predicate '${pname}' is referenced before declaration", __FUNCTION__);
                                return NULL;
                        }
                        return $self ($ptable[$pname], $tagchain, $ptable);
                case 'LEX_TRUE':
                        return TRUE;
                case 'LEX_FALSE':
                        return FALSE;
                case 'SYNT_NOT_EXPR':
                        $tmp = $self ($expr['load'], $tagchain, $ptable);
                        if ($tmp === TRUE)
                                return FALSE;
                        elseif ($tmp === FALSE)
                                return TRUE;
                        else
                                return $tmp;
                case 'SYNT_AND_EXPR': // binary AND
                        if (FALSE == $self ($expr['left'], $tagchain, $ptable))
                                return FALSE; // early failure
                        return $self ($expr['right'], $tagchain, $ptable);
                case 'SYNT_EXPR': // binary OR
                        if (TRUE == $self ($expr['left'], $tagchain, $ptable))
                                return TRUE; // early success
                        return $self ($expr['right'], $tagchain, $ptable);
                default:
                        if (!$silent)
                                showWarning ("Evaluation error, cannot process expression type '${expr['type']}'", __FUNCTION__);
                        return NULL;
                        break;
        }
}

// Tell, if the given expression is true for the given entity. Take complete record on input.
function judgeCell ($cell, $expression)
{
        global $pTable;
        return eval_expression
        (
                $expression,
                array_merge
                (
                        $cell['etags'],
                        $cell['itags'],
                        $cell['atags']
                ),
                $pTable,
                TRUE
        );
}

// Tell, if a constraint from config option permits given record.
function considerConfiguredConstraint ($cell, $varname)
{
        if (!strlen (getConfigVar ($varname)))
                return TRUE; // no restriction
        global $parseCache;
        if (!isset ($parseCache[$varname]))
                // getConfigVar() doesn't re-read the value from DB because of its
                // own cache, so there is no race condition here between two calls.
                $parseCache[$varname] = spotPayload (getConfigVar ($varname), 'SYNT_EXPR');
        if ($parseCache[$varname]['result'] != 'ACK')
                return FALSE; // constraint set, but cannot be used due to compilation error
        return judgeCell ($cell, $parseCache[$varname]['load']);
}

// Return list of records in the given realm, which conform to
// the given RackCode expression. If the realm is unknown or text
// doesn't validate as a RackCode expression, return NULL.
// Otherwise (successful scan) return a list of all matched
// records, even if the list is empty (array() !== NULL). If the
// text is an empty string, return all found records in the given
// realm.
function scanRealmByText ($realm = NULL, $ftext = '')
{
        switch ($realm)
        {
        case 'object':
        case 'user':
        case 'ipv4net':
        case 'file':
        case 'ipv4vs':
        case 'ipv4rspool':
                if (!strlen ($ftext = trim ($ftext)))
                        $fexpr = array();
                else
                {
                        $fparse = spotPayload ($ftext, 'SYNT_EXPR');
                        if ($fparse['result'] != 'ACK')
                                return NULL;
                        $fexpr = $fparse['load'];
                }
                return filterCellList (listCells ($realm), $fexpr);
        default:
                throw new InvalidArgException ('$realm', $realm);
        }

}

function getIPv4VSOptions ()
{
        $ret = array();
        foreach (listCells ('ipv4vs') as $vsid => $vsinfo)
                $ret[$vsid] = $vsinfo['dname'] . (!strlen ($vsinfo['name']) ? '' : " (${vsinfo['name']})");
        return $ret;
}

function getIPv4RSPoolOptions ()
{
        $ret = array();
        foreach (listCells ('ipv4rspool') as $pool_id => $poolInfo)
                $ret[$pool_id] = $poolInfo['name'];
        return $ret;
}

// Derive a complete cell structure from the given username regardless
// if it is a local account or not.
function constructUserCell ($username)
{
        if (NULL !== ($userid = getUserIDByUsername ($username)))
                return spotEntity ('user', $userid);
        $ret = array
        (
                'realm' => 'user',
                'user_name' => $username,
                'user_realname' => '',
                'etags' => array(),
                'itags' => array(),
        );
        $ret['atags'] = generateEntityAutoTags ($ret);
        return $ret;
}

// Let's have this debug helper here to enable debugging of process.php w/o interface.php.
function dump ($var)
{
        echo '<div align=left><pre>';
        print_r ($var);
        echo '</pre></div>';
}

function getTagChart ($limit = 0, $realm = 'total', $special_tags = array())
{
        global $taglist;
        // first build top-N chart...
        $toplist = array();
        foreach ($taglist as $taginfo)
                if (isset ($taginfo['refcnt'][$realm]))
                        $toplist[$taginfo['id']] = $taginfo['refcnt'][$realm];
        arsort ($toplist, SORT_NUMERIC);
        $ret = array();
        $done = 0;
        foreach (array_keys ($toplist) as $tag_id)
        {
                $ret[$tag_id] = $taglist[$tag_id];
                if (++$done == $limit)
                        break;
        }
        // ...then make sure, that every item of the special list is shown
        // (using the same sort order)
        $extra = array();
        foreach ($special_tags as $taginfo)
                if (!array_key_exists ($taginfo['id'], $ret))
                        $extra[$taginfo['id']] = $taglist[$taginfo['id']]['refcnt'][$realm];
        arsort ($extra, SORT_NUMERIC);
        foreach (array_keys ($extra) as $tag_id)
                $ret[] = $taglist[$tag_id];
        return $ret;
}

function decodeObjectType ($objtype_id, $style = 'r')
{
        static $types = array();
        if (!count ($types))
                $types = array
                (
                        'r' => readChapter (CHAP_OBJTYPE),
                        'a' => readChapter (CHAP_OBJTYPE, 'a'),
                        'o' => readChapter (CHAP_OBJTYPE, 'o')
                );
        return $types[$style][$objtype_id];
}

function isolatedPermission ($p, $t, $cell)
{
        // This function is called from both "file" page and a number of other pages,
        // which have already fixed security context and authorized the user for it.
        // OTOH, it is necessary here to authorize against the current file, which
        // means saving the current context and building a new one.
        global
                $expl_tags,
                $impl_tags,
                $target_given_tags,
                $auto_tags;
        // push current context
        $orig_expl_tags = $expl_tags;
        $orig_impl_tags = $impl_tags;
        $orig_target_given_tags = $target_given_tags;
        $orig_auto_tags = $auto_tags;
        // retarget
        fixContext ($cell);
        // remember decision
        $ret = permitted ($p, $t);
        // pop context
        $expl_tags = $orig_expl_tags;
        $impl_tags = $orig_impl_tags;
        $target_given_tags = $orig_target_given_tags;
        $auto_tags = $orig_auto_tags;
        return $ret;
}

function getPortListPrefs()
{
        $ret = array();
        if (0 >= ($ret['iif_pick'] = getConfigVar ('DEFAULT_PORT_IIF_ID')))
                $ret['iif_pick'] = 1;
        $ret['oif_picks'] = array();
        foreach (explode (';', getConfigVar ('DEFAULT_PORT_OIF_IDS')) as $tmp)
        {
                $tmp = explode ('=', trim ($tmp));
                if (count ($tmp) == 2 and $tmp[0] > 0 and $tmp[1] > 0)
                        $ret['oif_picks'][$tmp[0]] = $tmp[1];
        }
        // enforce default value
        if (!array_key_exists (1, $ret['oif_picks']))
                $ret['oif_picks'][1] = 24;
        $ret['selected'] = $ret['iif_pick'] . '-' . $ret['oif_picks'][$ret['iif_pick']];
        return $ret;
}

// Return data for printNiftySelect() with port type options. All OIF options
// for the default IIF will be shown, but only the default OIFs will be present
// for each other IIFs. IIFs, for which there is no default OIF, will not
// be listed.
// This SELECT will be used for the "add new port" form.
function getNewPortTypeOptions()
{
        $ret = array();
        $prefs = getPortListPrefs();
        foreach (getPortInterfaceCompat() as $row)
        {
                if ($row['iif_id'] == $prefs['iif_pick'])
                        $optgroup = $row['iif_name'];
                elseif (array_key_exists ($row['iif_id'], $prefs['oif_picks']) and $prefs['oif_picks'][$row['iif_id']] == $row['oif_id'])
                        $optgroup = 'other';
                else
                        continue;
                if (!array_key_exists ($optgroup, $ret))
                        $ret[$optgroup] = array();
                $ret[$optgroup][$row['iif_id'] . '-' . $row['oif_id']] = $row['oif_name'];
        }
        return $ret;
}

// Return a serialized version of VLAN configuration for a port.
// If a native VLAN is defined, print it first. All other VLANs
// are tagged and are listed after a plus sign. When no configuration
// is set for a port, return "default" string.
function serializeVLANPack ($vlanport)
{
        if (!array_key_exists ('mode', $vlanport))
                return 'error';
        switch ($vlanport['mode'])
        {
        case 'none':
                return 'none';
        case 'access':
                $ret = 'A';
                break;
        case 'trunk':
                $ret = 'T';
                break;
        case 'uplink':
                $ret = 'U';
                break;
        case 'downlink':
                $ret = 'D';
                break;
        default:
                return 'error';
        }
        $tagged = array();
        foreach ($vlanport['allowed'] as $vlan_id)
                if ($vlan_id != $vlanport['native'])
                        $tagged[] = $vlan_id;
        sort ($tagged);
        $ret .= $vlanport['native'] ? $vlanport['native'] : '';
        $tagged_bits = array();
        $id_from = $id_to = 0;
        foreach ($tagged as $next_id)
        {
                if ($id_to)
                {
                        if ($next_id == $id_to + 1) // merge
                        {
                                $id_to = $next_id;
                                continue;
                        }
                        // flush
                        $tagged_bits[] = $id_from == $id_to ? $id_from : "${id_from}-${id_to}";
                }
                $id_from = $id_to = $next_id; // start next pair
        }
        // pull last pair
        if ($id_to)
                $tagged_bits[] = $id_from == $id_to ? $id_from : "${id_from}-${id_to}";
        if (count ($tagged))
                $ret .= '+' . implode (', ', $tagged_bits);
        return strlen ($ret) ? $ret : 'default';
}

// Decode VLAN compound key (which is a string formatted DOMAINID-VLANID) and
// return the numbers as an array of two.
function decodeVLANCK ($string)
{
        $matches = array();
        if (1 != preg_match ('/^([[:digit:]]+)-([[:digit:]]+)$/', $string, $matches))
                throw new InvalidArgException ('VLAN compound key', $string);
        return array ($matches[1], $matches[2]);
}

// Return VLAN name formatted for HTML output (note, that input
// argument comes from database unescaped).
function formatVLANName ($vlaninfo, $context = 'markup long')
{
        switch ($context)
        {
        case 'option':
                $ret = $vlaninfo['vlan_id'];
                if ($vlaninfo['vlan_descr'] != '')
                        $ret .= ' ' . niftyString ($vlaninfo['vlan_descr']);
                return $ret;
        case 'label':
                $ret = $vlaninfo['vlan_id'];
                if ($vlaninfo['vlan_descr'] != '')
                        $ret .= ' <i>(' . niftyString ($vlaninfo['vlan_descr']) . ')</i>';
                return $ret;
        case 'plain long':
                $ret = 'VLAN' . $vlaninfo['vlan_id'];
                if ($vlaninfo['vlan_descr'] != '')
                        $ret .= ' (' . niftyString ($vlaninfo['vlan_descr'], 20, FALSE) . ')';
                return $ret;
        case 'hyperlink':
                $ret = '<a href="';
                $ret .= makeHref (array ('page' => 'vlan', 'vlan_ck' => $vlaninfo['domain_id'] . '-' . $vlaninfo['vlan_id']));
                $ret .= '">' . formatVLANName ($vlaninfo, 'markup long') . '</a>';
                return $ret;
        case 'markup long':
        default:
                $ret = 'VLAN' . $vlaninfo['vlan_id'];
                $ret .= ' @' . niftyString ($vlaninfo['domain_descr']);
                if ($vlaninfo['vlan_descr'] != '')
                        $ret .= ' <i>(' . niftyString ($vlaninfo['vlan_descr']) . ')</i>';
                return $ret;
        }
}

// map interface name
function ios12ShortenIfName ($ifname)
{
        $ifname = preg_replace ('@^Eth(?:ernet)?(.+)$@', 'e\\1', $ifname);
        $ifname = preg_replace ('@^FastEthernet(.+)$@', 'fa\\1', $ifname);
        $ifname = preg_replace ('@^GigabitEthernet(.+)$@', 'gi\\1', $ifname);
        $ifname = preg_replace ('@^TenGigabitEthernet(.+)$@', 'te\\1', $ifname);
        $ifname = preg_replace ('@^Port-channel(.+)$@', 'po\\1', $ifname);
        $ifname = preg_replace ('@^XGigabitEthernet(.+)$@', 'xg\\1', $ifname);
        $ifname = strtolower ($ifname);
        return $ifname;
}

function iosParseVLANString ($string)
{
        $ret = array();
        foreach (explode (',', $string) as $item)
        {
                $matches = array();
                $item = trim ($item, ' ');
                if (preg_match ('/^([[:digit:]]+)$/', $item, $matches))
                        $ret[] = $matches[1];
                elseif (preg_match ('/^([[:digit:]]+)-([[:digit:]]+)$/', $item, $matches))
                        $ret = array_merge ($ret, range ($matches[1], $matches[2]));
        }
        return $ret;
}

// Scan given array and return the key, which addresses the first item
// with requested column set to given value (or NULL if there is none such).
// Note that 0 and NULL mean completely different things and thus
// require strict checking (=== and !===).
function scanArrayForItem ($table, $scan_column, $scan_value)
{
        foreach ($table as $key => $row)
                if ($row[$scan_column] == $scan_value)
                        return $key;
        return NULL;
}

// Return TRUE, if every value of A1 is present in A2 and vice versa,
// regardless of each array's sort order and indexing.
function array_values_same ($a1, $a2)
{
        return !count (array_diff ($a1, $a2)) and !count (array_diff ($a2, $a1));
}

// Use the VLAN switch template to set VST role for each port of
// the provided list. Return resulting list.
function apply8021QOrder ($vst_id, $portlist)
{
        $vst = getVLANSwitchTemplate ($vst_id);
        foreach (array_keys ($portlist) as $port_name)
        {
                foreach ($vst['rules'] as $rule)
                        if (preg_match ($rule['port_pcre'], $port_name))
                        {
                                $portlist[$port_name]['vst_role'] = $rule['port_role'];
                                $portlist[$port_name]['wrt_vlans'] = buildVLANFilter ($rule['port_role'], $rule['wrt_vlans']);
                                continue 2;
                        }
                $portlist[$port_name]['vst_role'] = 'none';
        }
        return $portlist;
}

// return a sequence of ranges for given string form and port role
function buildVLANFilter ($role, $string)
{
        // set base
        switch ($role)
        {
        case 'access': // 1-4094
                $min = VLAN_MIN_ID;
                $max = VLAN_MAX_ID;
                break;
        case 'trunk': // 2-4094
        case 'uplink':
        case 'downlink':
        case 'anymode':
                $min = VLAN_MIN_ID + 1;
                $max = VLAN_MAX_ID;
                break;
        default: // none
                return array();
        }
        if ($string == '') // fast track
                return array (array ('from' => $min, 'to' => $max));
        // transform
        $vlanidlist = array();
        foreach (iosParseVLANString ($string) as $vlan_id)
                if ($min <= $vlan_id and $vlan_id <= $max)
                        $vlanidlist[] = $vlan_id;
        return listToRanges ($vlanidlist);
}

// pack set of integers into list of integer ranges
// e.g. (1, 2, 3, 5, 6, 7, 9, 11) => ((1, 3), (5, 7), (9, 9), (11, 11))
// The second argument, when it is different from 0, limits amount of
// items in each generated range.
function listToRanges ($vlanidlist, $limit = 0)
{
        sort ($vlanidlist);
        $ret = array();
        $from = $to = NULL;
        foreach ($vlanidlist as $vlan_id)
                if ($from == NULL)
                {
                        if ($limit == 1)
                                $ret[] = array ('from' => $vlan_id, 'to' => $vlan_id);
                        else
                                $from = $to = $vlan_id;
                }
                elseif ($to + 1 == $vlan_id)
                {
                        $to = $vlan_id;
                        if ($to - $from + 1 == $limit)
                        {
                                // cut accumulated range and start over
                                $ret[] = array ('from' => $from, 'to' => $to);
                                $from = $to = NULL;
                        }
                }
                else
                {
                        $ret[] = array ('from' => $from, 'to' => $to);
                        $from = $to = $vlan_id;
                }
        if ($from != NULL)
                $ret[] = array ('from' => $from, 'to' => $to);
        return $ret;
}

// return TRUE, if given VLAN ID belongs to one of filter's ranges
function matchVLANFilter ($vlan_id, $vfilter)
{
        foreach ($vfilter as $range)
                if ($range['from'] <= $vlan_id and $vlan_id <= $range['to'])
                        return TRUE;
        return FALSE;
}

function exportSwitch8021QConfig
(
        $vswitch,
        $device_vlanlist,
        $before,
        $changes
)
{
        // only ignore VLANs, which exist and are explicitly shown as "alien"
        $old_managed_vlans = array();
        $domain_vlanlist = getDomainVLANs ($vswitch['domain_id']);
        foreach ($device_vlanlist as $vlan_id)
                if
                (
                        !array_key_exists ($vlan_id, $domain_vlanlist) or
                        $domain_vlanlist[$vlan_id]['vlan_type'] != 'alien'
                )
                        $old_managed_vlans[] = $vlan_id;
        $ports_to_do = array();
        $after = $before;
        foreach ($changes as $port_name => $port)
        {
                $ports_to_do[$port_name] = array
                (
                        'old_mode' => $before[$port_name]['mode'],
                        'old_allowed' => $before[$port_name]['allowed'],
                        'old_native' => $before[$port_name]['native'],
                        'new_mode' => $port['mode'],
                        'new_allowed' => $port['allowed'],
                        'new_native' => $port['native'],
                );
                $after[$port_name] = $port;
        }
        // New VLAN table is a union of:
        // 1. all compulsory VLANs
        // 2. all "current" non-alien allowed VLANs of those ports, which are left
        //    intact (regardless if a VLAN exists in VLAN domain, but looking,
        //    if it is present in device's own VLAN table)
        // 3. all "new" allowed VLANs of those ports, which we do "push" now
        // Like for old_managed_vlans, a VLANs is never listed, only if it
        // exists and belongs to "alien" type.
        $new_managed_vlans = array();
        // 1
        foreach ($domain_vlanlist as $vlan_id => $vlan)
                if ($vlan['vlan_type'] == 'compulsory')
                        $new_managed_vlans[] = $vlan_id;
        // 2
        foreach ($before as $port_name => $port)
                if (!array_key_exists ($port_name, $changes))
                        foreach ($port['allowed'] as $vlan_id)
                        {
                                if (in_array ($vlan_id, $new_managed_vlans))
                                        continue;
                                if
                                (
                                        array_key_exists ($vlan_id, $domain_vlanlist) and
                                        $domain_vlanlist[$vlan_id]['vlan_type'] == 'alien'
                                )
                                        continue;
                                if (in_array ($vlan_id, $device_vlanlist))
                                        $new_managed_vlans[] = $vlan_id;
                        }
        // 3
        foreach ($changes as $port)
                foreach ($port['allowed'] as $vlan_id)
                        if
                        (
                                $domain_vlanlist[$vlan_id]['vlan_type'] == 'ondemand' and
                                !in_array ($vlan_id, $new_managed_vlans)
                        )
                                $new_managed_vlans[] = $vlan_id;
        $crq = array();
        // Before removing each old VLAN as such it is necessary to unassign
        // ports from it (to remove VLAN from each ports' list of "allowed"
        // VLANs). This change in turn requires, that a port's "native"
        // VLAN isn't set to the one being removed from its "allowed" list.
        foreach ($ports_to_do as $port_name => $port)
                switch ($port['old_mode'] . '->' . $port['new_mode'])
                {
                case 'trunk->trunk':
                        // "old" native is set and differs from the "new" native
                        if ($port['old_native'] and $port['old_native'] != $port['new_native'])
                                $crq[] = array
                                (
                                        'opcode' => 'unset native',
                                        'arg1' => $port_name,
                                        'arg2' => $port['old_native'],
                                );
                        if (count ($tmp = array_diff ($port['old_allowed'], $port['new_allowed'])))
                                $crq[] = array
                                (
                                        'opcode' => 'rem allowed',
                                        'port' => $port_name,
                                        'vlans' => $tmp,
                                );
                        break;
                case 'access->access':
                        if ($port['old_native'] and $port['old_native'] != $port['new_native'])
                                $crq[] = array
                                (
                                        'opcode' => 'unset access',
                                        'arg1' => $port_name,
                                        'arg2' => $port['old_native'],
                                );
                        break;
                case 'access->trunk':
                        $crq[] = array
                        (
                                'opcode' => 'unset access',
                                'arg1' => $port_name,
                                'arg2' => $port['old_native'],
                        );
                        break;
                case 'trunk->access':
                        if ($port['old_native'])
                                $crq[] = array
                                (
                                        'opcode' => 'unset native',
                                        'arg1' => $port_name,
                                        'arg2' => $port['old_native'],
                                );
                        if (count ($port['old_allowed']))
                                $crq[] = array
                                (
                                        'opcode' => 'rem allowed',
                                        'port' => $port_name,
                                        'vlans' => $port['old_allowed'],
                                );
                        break;
                default:
                        throw new InvalidArgException ('ports_to_do', '(hidden)', 'error in structure');
                }
        // Now it is safe to unconfigure VLANs, which still exist on device,
        // but are not present on the "new" list.
        // FIXME: put all IDs into one pseudo-command to make it easier
        // for translators to create/destroy VLANs in batches, where
        // target platform allows them to do.
        foreach (array_diff ($old_managed_vlans, $new_managed_vlans) as $vlan_id)
                $crq[] = array
                (
                        'opcode' => 'destroy VLAN',
                        'arg1' => $vlan_id,
                );
        // Configure VLANs, which must be present on the device, but are not yet.
        foreach (array_diff ($new_managed_vlans, $old_managed_vlans) as $vlan_id)
                $crq[] = array
                (
                        'opcode' => 'create VLAN',
                        'arg1' => $vlan_id,
                );
        // Now, when all new VLANs are created (queued), it is safe to assign (queue)
        // ports to the new VLANs.
        foreach ($ports_to_do as $port_name => $port)
                switch ($port['old_mode'] . '->' . $port['new_mode'])
                {
                case 'trunk->trunk':
                        // For each allowed VLAN, which is present on the "new" list and missing from
                        // the "old" one, queue a command to assign current port to that VLAN.
                        if (count ($tmp = array_diff ($port['new_allowed'], $port['old_allowed'])))
                                $crq[] = array
                                (
                                        'opcode' => 'add allowed',
                                        'port' => $port_name,
                                        'vlans' => $tmp,
                                );
                        // One of the "allowed" VLANs for this port may probably be "native".
                        // "new native" is set and differs from "old native"
                        if ($port['new_native'] and $port['new_native'] != $port['old_native'])
                                $crq[] = array
                                (
                                        'opcode' => 'set native',
                                        'arg1' => $port_name,
                                        'arg2' => $port['new_native'],
                                );
                        break;
                case 'access->access':
                        if ($port['new_native'] and $port['new_native'] != $port['old_native'])
                                $crq[] = array
                                (
                                        'opcode' => 'set access',
                                        'arg1' => $port_name,
                                        'arg2' => $port['new_native'],
                                );
                        break;
                case 'access->trunk':
                        $crq[] = array
                        (
                                'opcode' => 'set mode',
                                'arg1' => $port_name,
                                'arg2' => $port['new_mode'],
                        );
                        if (count ($port['new_allowed']))
                                $crq[] = array
                                (
                                        'opcode' => 'add allowed',
                                        'port' => $port_name,
                                        'vlans' => $port['new_allowed'],
                                );
                        if ($port['new_native'])
                                $crq[] = array
                                (
                                        'opcode' => 'set native',
                                        'arg1' => $port_name,
                                        'arg2' => $port['new_native'],
                                );
                        break;
                case 'trunk->access':
                        $crq[] = array
                        (
                                'opcode' => 'set mode',
                                'arg1' => $port_name,
                                'arg2' => $port['new_mode'],
                        );
                        $crq[] = array
                        (
                                'opcode' => 'set access',
                                'arg1' => $port_name,
                                'arg2' => $port['new_native'],
                        );
                        break;
                default:
                        throw new InvalidArgException ('ports_to_do', '(hidden)', 'error in structure');
                }
        if (count ($crq))
        {
                array_unshift ($crq, array ('opcode' => 'begin configuration'));
                $crq[] = array ('opcode' => 'end configuration');
                if (considerConfiguredConstraint (spotEntity ('object', $vswitch['object_id']), '8021Q_WRI_AFTER_CONFT_LISTSRC'))
                        $crq[] = array ('opcode' => 'save configuration');
                setDevice8021QConfig ($vswitch['object_id'], $crq);
        }
        return count ($crq);
}

// filter list of changed ports to cancel changes forbidden by VST and domain
function filter8021QChangeRequests
(
        $domain_vlanlist,
        $before,  // current saved configuration of all ports
        $changes  // changed ports with VST markup
)
{
        $domain_immune_vlans = array();
        foreach ($domain_vlanlist as $vlan_id => $vlan)
                if ($vlan['vlan_type'] == 'alien')
                        $domain_immune_vlans[] = $vlan_id;
        $ret = array();
        foreach ($changes as $port_name => $port)
        {
                // VST violation ?
                if (!goodModeForVSTRole ($port['mode'], $port['vst_role']))
                        continue; // ignore change request
                // find and cancel any changes regarding immune VLANs
                switch ($port['mode'])
                {
                case 'access':
                        foreach ($domain_immune_vlans as $immune)
                                // Reverting an attempt to set an access port from
                                // "normal" VLAN to immune one (or vice versa) requires
                                // special handling, becase the calling function has
                                // discarded the old contents of 'allowed' for current port.
                                if
                                (
                                        $before[$port_name]['native'] == $immune or
                                        $port['native'] == $immune
                                )
                                {
                                        $port['native'] = $before[$port_name]['native'];
                                        $port['allowed'] = array ($port['native']);
                                        // Such reversal happens either once or never for an
                                        // access port.
                                        break;
                                }
                        break;
                case 'trunk':
                        foreach ($domain_immune_vlans as $immune)
                                if (in_array ($immune, $before[$port_name]['allowed'])) // was allowed before
                                {
                                        if (!in_array ($immune, $port['allowed']))
                                                $port['allowed'][] = $immune; // restore
                                        if ($before[$port_name]['native'] == $immune) // and was native
                                                $port['native'] = $immune; // also restore
                                }
                                else // wasn't
                                {
                                        if (in_array ($immune, $port['allowed']))
                                                unset ($port['allowed'][array_search ($immune, $port['allowed'])]); // cancel
                                        if ($port['native'] == $immune)
                                                $port['native'] = $before[$port_name]['native'];
                                }
                        break;
                default:
                        throw new InvalidArgException ('mode', $port['mode']);
                }
                // save work
                $ret[$port_name] = $port;
        }
        return $ret;
}

// take port list with order applied and return uplink ports in the same format
function produceUplinkPorts ($domain_vlanlist, $portlist)
{
        $ret = array();
        $employed = array();
        foreach ($domain_vlanlist as $vlan_id => $vlan)
                if ($vlan['vlan_type'] == 'compulsory')
                        $employed[] = $vlan_id;
        foreach ($portlist as $port_name => $port)
                if ($port['vst_role'] != 'uplink')
                        foreach ($port['allowed'] as $vlan_id)
                                if (!in_array ($vlan_id, $employed))
                                        $employed[] = $vlan_id;
        foreach ($portlist as $port_name => $port)
                if ($port['vst_role'] == 'uplink')
                {
                        $employed_here = array();
                        foreach ($employed as $vlan_id)
                                if (matchVLANFilter ($vlan_id, $port['wrt_vlans']))
                                        $employed_here[] = $vlan_id;
                        $ret[$port_name] = array
                        (
                                'vst_role' => 'uplink',
                                'mode' => 'trunk',
                                'allowed' => $employed_here,
                                'native' => 0,
                        );
                }
        return $ret;
}

function same8021QConfigs ($a, $b)
{
        return  $a['mode'] == $b['mode'] &&
                array_values_same ($a['allowed'], $b['allowed']) &&
                $a['native'] == $b['native'];
}

// Return TRUE, if the port can be edited by the user.
function editable8021QPort ($port)
{
        return in_array ($port['vst_role'], array ('trunk', 'access', 'anymode'));
}

// Decide, whether the given 802.1Q port mode is permitted by
// VST port role.
function goodModeForVSTRole ($mode, $role)
{
        switch ($mode)
        {
        case 'access':
                return in_array ($role, array ('access', 'anymode'));
        case 'trunk':
                return in_array ($role, array ('trunk', 'uplink', 'downlink', 'anymode'));
        default:
                throw new InvalidArgException ('mode', $mode);
        }
}

/*

Relation between desired (D), cached (C) and running (R)
copies of switch ports (P) list.

  D         C           R
+---+     +---+       +---+
| P |-----| P |-?  +--| P |
+---+     +---+   /   +---+
| P |-----| P |--+  ?-| P |
+---+     +---+       +---+
| P |-----| P |-------| P |
+---+     +---+       +---+
| P |-----| P |--+  ?-| P |
+---+     +---+   \   +---+
| P |-----| P |--+ +--| P |
+---+     +---+   \   +---+
                   +--| P |
                      +---+
                    ?-| P |
                      +---+

A modified local version of a port in "conflict" state ignores remote
changes until remote change maintains its difference. Once both edits
match, the local copy "locks" on the remote and starts tracking it.

v
a           "o" -- remOte version
l           "l" -- Local version
u           "b" -- Both versions
e

^
|         o           b
|           o
| l l l l l l b     b
|   o   o       b
| o               b
|
|     o
|
|
0----------------------------------------------> time

*/
function get8021QSyncOptions
(
        $vswitch,
        $D, // desired config
        $C, // cached config
        $R  // running-config
)
{
        $default_port = array
        (
                'mode' => 'access',
                'allowed' => array (VLAN_DFL_ID),
                'native' => VLAN_DFL_ID,
        );
        $ret = array();
        $allports = array();
        foreach (array_unique (array_merge (array_keys ($C), array_keys ($R))) as $pn)
                $allports[$pn] = array();
        foreach (apply8021QOrder ($vswitch['template_id'], $allports) as $pn => $port)
        {
                // catch anomalies early
                if ($port['vst_role'] == 'none')
                {
                        if ((!array_key_exists ($pn, $R) or $R[$pn]['mode'] == 'none') and !array_key_exists ($pn, $C))
                                $ret[$pn] = array ('status' => 'none');
                        else
                                $ret[$pn] = array
                                (
                                        'status' => 'martian_conflict',
                                        'left' => array_key_exists ($pn, $C) ? $C[$pn] : array ('mode' => 'none'),
                                        'right' => array_key_exists ($pn, $R) ? $R[$pn] : array ('mode' => 'none'),
                                );
                        continue;
                }
                elseif ((!array_key_exists ($pn, $R) or $R[$pn]['mode'] == 'none') and array_key_exists ($pn, $C))
                {
                        $ret[$pn] = array
                        (
                                'status' => 'martian_conflict',
                                'left' => array_key_exists ($pn, $C) ? $C[$pn] : array ('mode' => 'none'),
                                'right' => array_key_exists ($pn, $R) ? $R[$pn] : array ('mode' => 'none'),
                        );
                        continue<