<?php
class PxeLinux
{
/**
* Takes a (partial) pxelinux menu and parses it into
* a PxeMenu object.
*
* @param string $input The pxelinux menu to parse
* @return ?PxeMenu the parsed menu, or null if input is not a PXELinux menu
*/
public static function parsePxeLinux(string $input, bool $isCp437): ?PxeMenu
{
if (empty($input))
return null;
if ($isCp437) {
$input = iconv('IBM437', 'UTF8//TRANSLIT//IGNORE', $input);
}
$menu = new PxeMenu;
$sectionPropMap = [
'menu label' => ['string', 'title'],
'menu default' => ['true', 'isDefault'],
'menu hide' => ['true', 'isHidden'],
'menu disabled' => ['true', 'isDisabled'],
'menu indent' => ['int', 'indent'],
'kernel' => ['string', 'kernel'],
'com32' => ['string', 'kernel'],
'pxe' => ['string', 'kernel'],
'initrd' => ['string', 'initrd'],
'append' => ['string', 'append'],
'ipappend' => ['int', 'ipAppend'],
'sysappend' => ['int', 'ipAppend'],
'localboot' => ['int', 'localBoot'],
];
$globalPropMap = [
'timeout' => ['int', 'timeoutMs', 100],
'totaltimeout' => ['int', 'totalTimeoutMs', 100],
'menu title' => ['string', 'title'],
'menu clear' => ['true', 'menuClear'],
'menu immediate' => ['true', 'immediateHotkeys'],
'ontimeout' => ['string', 'timeoutLabel'],
'default' => ['string', 'default'],
];
$lines = preg_split('/[\r\n]+/', $input);
$section = null;
$count = count($lines);
for ($li = 0; $li < $count; ++$li) {
$line =& $lines[$li];
if (!preg_match('/^\s*([^m]\S*|menu\s+\S+)(\s+.*?|)\s*$/i', $line, $out))
continue;
$val = trim($out[2]);
$key = trim($out[1]);
$key = strtolower($key);
$key = preg_replace('/\s+/', ' ', $key);
if ($key === 'label') {
if ($section !== null) {
$menu->sections[] = $section;
}
$section = new PxeSection($val);
} elseif ($key === 'menu separator') {
if ($section !== null) {
$menu->sections[] = $section;
$section = null;
}
$menu->sections[] = new PxeSection(null);
} elseif (self::handleKeyword($key, $val, $globalPropMap, $menu)) {
continue;
} elseif ($section === null) {
continue;
} elseif ($key === 'text' && strtolower($val) === 'help') {
$text = '';
while (++$li < $count) {
$line =& $lines[$li];
if (strtolower(trim($line)) === 'endtext')
break;
$text .= $line . "\n";
}
$section->helpText = $text;
} elseif (self::handleKeyword($key, $val, $sectionPropMap, $section)) {
//continue;
}
}
if ($section !== null) {
$menu->sections[] = $section;
}
if (empty($menu->sections))
return null; // Probably not a PXE menu but random text?
foreach ($menu->sections as $section) {
$section->mangle();
}
return $menu;
}
/**
* Check if keyword is valid and if so, add its interpreted value
* to the given object. The map to look up the keyword has to be passed
* as well as the object to set the value in. Map and object should
* obviously match.
*
* @param string $key keyword of parsed line
* @param string $val raw value of currently parsed line (empty if not present)
* @param array $map Map in which $key is looked up as key
* @param PxeMenu|PxeSection $object The object to set the parsed and sanitized value in
* @return bool true if the value was found in the map (and set in the object), false otherwise
*/
private static function handleKeyword(string $key, string $val, array $map, $object): bool
{
if (!isset($map[$key]))
return false;
$opt = $map[$key];
// opt[0] is the type the value should be cast to; special case "true" means
// this is a bool option that will be set as soon as the keyword is present,
// as it doesn't have any parameters
if ($opt[0] === 'true') {
$val = true;
} else {
settype($val, $opt[0]);
}
// If opt[2] is present it's a multiplier for the value
if (isset($opt[2])) {
$val *= $opt[2];
}
$object->{$opt[1]} = $val;
return true;
}
}
