aboutsummaryrefslogtreecommitdiffstats
path: root/vendor/ezyang/htmlpurifier/library/HTMLPurifier/AttrDef.php
blob: 739646fa7c26c4f4572d33b5af5d85a4be6b2db6 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
<?php

/**
 * Base class for all validating attribute definitions.
 *
 * This family of classes forms the core for not only HTML attribute validation,
 * but also any sort of string that needs to be validated or cleaned (which
 * means CSS properties and composite definitions are defined here too).
 * Besides defining (through code) what precisely makes the string valid,
 * subclasses are also responsible for cleaning the code if possible.
 */

abstract class HTMLPurifier_AttrDef
{

    /**
     * Tells us whether or not an HTML attribute is minimized.
     * Has no meaning in other contexts.
     * @type bool
     */
    public $minimized = false;

    /**
     * Tells us whether or not an HTML attribute is required.
     * Has no meaning in other contexts
     * @type bool
     */
    public $required = false;

    /**
     * Validates and cleans passed string according to a definition.
     *
     * @param string $string String to be validated and cleaned.
     * @param HTMLPurifier_Config $config Mandatory HTMLPurifier_Config object.
     * @param HTMLPurifier_Context $context Mandatory HTMLPurifier_Context object.
     */
    abstract public function validate($string, $config, $context);

    /**
     * Convenience method that parses a string as if it were CDATA.
     *
     * This method process a string in the manner specified at
     * <http://www.w3.org/TR/html4/types.html#h-6.2> by removing
     * leading and trailing whitespace, ignoring line feeds, and replacing
     * carriage returns and tabs with spaces.  While most useful for HTML
     * attributes specified as CDATA, it can also be applied to most CSS
     * values.
     *
     * @note This method is not entirely standards compliant, as trim() removes
     *       more types of whitespace than specified in the spec. In practice,
     *       this is rarely a problem, as those extra characters usually have
     *       already been removed by HTMLPurifier_Encoder.
     *
     * @warning This processing is inconsistent with XML's whitespace handling
     *          as specified by section 3.3.3 and referenced XHTML 1.0 section
     *          4.7.  However, note that we are NOT necessarily
     *          parsing XML, thus, this behavior may still be correct. We
     *          assume that newlines have been normalized.
     */
    public function parseCDATA($string)
    {
        $string = trim($string);
        $string = str_replace(array("\n", "\t", "\r"), ' ', $string);
        return $string;
    }

    /**
     * Factory method for creating this class from a string.
     * @param string $string String construction info
     * @return HTMLPurifier_AttrDef Created AttrDef object corresponding to $string
     */
    public function make($string)
    {
        // default implementation, return a flyweight of this object.
        // If $string has an effect on the returned object (i.e. you
        // need to overload this method), it is best
        // to clone or instantiate new copies. (Instantiation is safer.)
        return $this;
    }

    /**
     * Removes spaces from rgb(0, 0, 0) so that shorthand CSS properties work
     * properly. THIS IS A HACK!
     * @param string $string a CSS colour definition
     * @return string
     */
    protected function mungeRgb($string)
    {
        $p = '\s*(\d+(\.\d+)?([%]?))\s*';

        if (preg_match('/(rgba|hsla)\(/', $string)) {
            return preg_replace('/(rgba|hsla)\('.$p.','.$p.','.$p.','.$p.'\)/', '\1(\2,\5,\8,\11)', $string);
        }

        return preg_replace('/(rgb|hsl)\('.$p.','.$p.','.$p.'\)/', '\1(\2,\5,\8)', $string);
    }

    /**
     * Parses a possibly escaped CSS string and returns the "pure"
     * version of it.
     */
    protected function expandCSSEscape($string)
    {
        // flexibly parse it
        $ret = '';
        for ($i = 0, $c = strlen($string); $i < $c; $i++) {
            if ($string[$i] === '\\') {
                $i++;
                if ($i >= $c) {
                    $ret .= '\\';
                    break;
                }
                if (ctype_xdigit($string[$i])) {
                    $code = $string[$i];
                    for ($a = 1, $i++; $i < $c && $a < 6; $i++, $a++) {
                        if (!ctype_xdigit($string[$i])) {
                            break;
                        }
                        $code .= $string[$i];
                    }
                    // We have to be extremely careful when adding
                    // new characters, to make sure we're not breaking
                    // the encoding.
                    $char = HTMLPurifier_Encoder::unichr(hexdec($code));
                    if (HTMLPurifier_Encoder::cleanUTF8($char) === '') {
                        continue;
                    }
                    $ret .= $char;
                    if ($i < $c && trim($string[$i]) !== '') {
                        $i--;
                    }
                    continue;
                }
                if ($string[$i] === "\n") {
                    continue;
                }
            }
            $ret .= $string[$i];
        }
        return $ret;
    }
}

// vim: et sw=4 sts=4