1<?php
2
3// constants are slow, so we use as few as possible
4if (!defined('HTMLPURIFIER_PREFIX')) {
5    define('HTMLPURIFIER_PREFIX', realpath(dirname(__FILE__) . '/..'));
6}
7
8// accomodations for versions earlier than 5.0.2
9// borrowed from PHP_Compat, LGPL licensed, by Aidan Lister <aidan@php.net>
10if (!defined('PHP_EOL')) {
11    switch (strtoupper(substr(PHP_OS, 0, 3))) {
12        case 'WIN':
13            define('PHP_EOL', "\r\n");
14            break;
15        case 'DAR':
16            define('PHP_EOL', "\r");
17            break;
18        default:
19            define('PHP_EOL', "\n");
20    }
21}
22
23/**
24 * Bootstrap class that contains meta-functionality for HTML Purifier such as
25 * the autoload function.
26 *
27 * @note
28 *      This class may be used without any other files from HTML Purifier.
29 */
30class HTMLPurifier_Bootstrap
31{
32
33    /**
34     * Autoload function for HTML Purifier
35     * @param string $class Class to load
36     * @return bool
37     */
38    public static function autoload($class)
39    {
40        $file = HTMLPurifier_Bootstrap::getPath($class);
41        if (!$file) {
42            return false;
43        }
44        // Technically speaking, it should be ok and more efficient to
45        // just do 'require', but Antonio Parraga reports that with
46        // Zend extensions such as Zend debugger and APC, this invariant
47        // may be broken.  Since we have efficient alternatives, pay
48        // the cost here and avoid the bug.
49        require_once HTMLPURIFIER_PREFIX . '/' . $file;
50        return true;
51    }
52
53    /**
54     * Returns the path for a specific class.
55     * @param string $class Class path to get
56     * @return string
57     */
58    public static function getPath($class)
59    {
60        if (strncmp('HTMLPurifier', $class, 12) !== 0) {
61            return false;
62        }
63        // Custom implementations
64        if (strncmp('HTMLPurifier_Language_', $class, 22) === 0) {
65            $code = str_replace('_', '-', substr($class, 22));
66            $file = 'HTMLPurifier/Language/classes/' . $code . '.php';
67        } else {
68            $file = str_replace('_', '/', $class) . '.php';
69        }
70        if (!file_exists(HTMLPURIFIER_PREFIX . '/' . $file)) {
71            return false;
72        }
73        return $file;
74    }
75
76    /**
77     * "Pre-registers" our autoloader on the SPL stack.
78     */
79    public static function registerAutoload()
80    {
81        $autoload = array('HTMLPurifier_Bootstrap', 'autoload');
82        if (($funcs = spl_autoload_functions()) === false) {
83            spl_autoload_register($autoload);
84        } elseif (function_exists('spl_autoload_unregister')) {
85            if (version_compare(PHP_VERSION, '5.3.0', '>=')) {
86                // prepend flag exists, no need for shenanigans
87                spl_autoload_register($autoload, true, true);
88            } else {
89                $buggy  = version_compare(PHP_VERSION, '5.2.11', '<');
90                $compat = version_compare(PHP_VERSION, '5.1.2', '<=') &&
91                          version_compare(PHP_VERSION, '5.1.0', '>=');
92                foreach ($funcs as $func) {
93                    if ($buggy && is_array($func)) {
94                        // :TRICKY: There are some compatibility issues and some
95                        // places where we need to error out
96                        $reflector = new ReflectionMethod($func[0], $func[1]);
97                        if (!$reflector->isStatic()) {
98                            throw new Exception(
99                                'HTML Purifier autoloader registrar is not compatible
100                                with non-static object methods due to PHP Bug #44144;
101                                Please do not use HTMLPurifier.autoload.php (or any
102                                file that includes this file); instead, place the code:
103                                spl_autoload_register(array(\'HTMLPurifier_Bootstrap\', \'autoload\'))
104                                after your own autoloaders.'
105                            );
106                        }
107                        // Suprisingly, spl_autoload_register supports the
108                        // Class::staticMethod callback format, although call_user_func doesn't
109                        if ($compat) {
110                            $func = implode('::', $func);
111                        }
112                    }
113                    spl_autoload_unregister($func);
114                }
115                spl_autoload_register($autoload);
116                foreach ($funcs as $func) {
117                    spl_autoload_register($func);
118                }
119            }
120        }
121    }
122}
123
124// vim: et sw=4 sts=4
125