Release 4.8.0
[htmlpurifier.git] / library / HTMLPurifier / VarParser.php
blob50cba6910db784fee6ac8af0b38f35c9b5542f55
1 <?php
3 /**
4 * Parses string representations into their corresponding native PHP
5 * variable type. The base implementation does a simple type-check.
6 */
7 class HTMLPurifier_VarParser
10 const STRING = 1;
11 const ISTRING = 2;
12 const TEXT = 3;
13 const ITEXT = 4;
14 const INT = 5;
15 const FLOAT = 6;
16 const BOOL = 7;
17 const LOOKUP = 8;
18 const ALIST = 9;
19 const HASH = 10;
20 const MIXED = 11;
22 /**
23 * Lookup table of allowed types. Mainly for backwards compatibility, but
24 * also convenient for transforming string type names to the integer constants.
26 public static $types = array(
27 'string' => self::STRING,
28 'istring' => self::ISTRING,
29 'text' => self::TEXT,
30 'itext' => self::ITEXT,
31 'int' => self::INT,
32 'float' => self::FLOAT,
33 'bool' => self::BOOL,
34 'lookup' => self::LOOKUP,
35 'list' => self::ALIST,
36 'hash' => self::HASH,
37 'mixed' => self::MIXED
40 /**
41 * Lookup table of types that are string, and can have aliases or
42 * allowed value lists.
44 public static $stringTypes = array(
45 self::STRING => true,
46 self::ISTRING => true,
47 self::TEXT => true,
48 self::ITEXT => true,
51 /**
52 * Validate a variable according to type.
53 * It may return NULL as a valid type if $allow_null is true.
55 * @param mixed $var Variable to validate
56 * @param int $type Type of variable, see HTMLPurifier_VarParser->types
57 * @param bool $allow_null Whether or not to permit null as a value
58 * @return string Validated and type-coerced variable
59 * @throws HTMLPurifier_VarParserException
61 final public function parse($var, $type, $allow_null = false)
63 if (is_string($type)) {
64 if (!isset(HTMLPurifier_VarParser::$types[$type])) {
65 throw new HTMLPurifier_VarParserException("Invalid type '$type'");
66 } else {
67 $type = HTMLPurifier_VarParser::$types[$type];
70 $var = $this->parseImplementation($var, $type, $allow_null);
71 if ($allow_null && $var === null) {
72 return null;
74 // These are basic checks, to make sure nothing horribly wrong
75 // happened in our implementations.
76 switch ($type) {
77 case (self::STRING):
78 case (self::ISTRING):
79 case (self::TEXT):
80 case (self::ITEXT):
81 if (!is_string($var)) {
82 break;
84 if ($type == self::ISTRING || $type == self::ITEXT) {
85 $var = strtolower($var);
87 return $var;
88 case (self::INT):
89 if (!is_int($var)) {
90 break;
92 return $var;
93 case (self::FLOAT):
94 if (!is_float($var)) {
95 break;
97 return $var;
98 case (self::BOOL):
99 if (!is_bool($var)) {
100 break;
102 return $var;
103 case (self::LOOKUP):
104 case (self::ALIST):
105 case (self::HASH):
106 if (!is_array($var)) {
107 break;
109 if ($type === self::LOOKUP) {
110 foreach ($var as $k) {
111 if ($k !== true) {
112 $this->error('Lookup table contains value other than true');
115 } elseif ($type === self::ALIST) {
116 $keys = array_keys($var);
117 if (array_keys($keys) !== $keys) {
118 $this->error('Indices for list are not uniform');
121 return $var;
122 case (self::MIXED):
123 return $var;
124 default:
125 $this->errorInconsistent(get_class($this), $type);
127 $this->errorGeneric($var, $type);
131 * Actually implements the parsing. Base implementation does not
132 * do anything to $var. Subclasses should overload this!
133 * @param mixed $var
134 * @param int $type
135 * @param bool $allow_null
136 * @return string
138 protected function parseImplementation($var, $type, $allow_null)
140 return $var;
144 * Throws an exception.
145 * @throws HTMLPurifier_VarParserException
147 protected function error($msg)
149 throw new HTMLPurifier_VarParserException($msg);
153 * Throws an inconsistency exception.
154 * @note This should not ever be called. It would be called if we
155 * extend the allowed values of HTMLPurifier_VarParser without
156 * updating subclasses.
157 * @param string $class
158 * @param int $type
159 * @throws HTMLPurifier_Exception
161 protected function errorInconsistent($class, $type)
163 throw new HTMLPurifier_Exception(
164 "Inconsistency in $class: " . HTMLPurifier_VarParser::getTypeName($type) .
165 " not implemented"
170 * Generic error for if a type didn't work.
171 * @param mixed $var
172 * @param int $type
174 protected function errorGeneric($var, $type)
176 $vtype = gettype($var);
177 $this->error("Expected type " . HTMLPurifier_VarParser::getTypeName($type) . ", got $vtype");
181 * @param int $type
182 * @return string
184 public static function getTypeName($type)
186 static $lookup;
187 if (!$lookup) {
188 // Lazy load the alternative lookup table
189 $lookup = array_flip(HTMLPurifier_VarParser::$types);
191 if (!isset($lookup[$type])) {
192 return 'unknown';
194 return $lookup[$type];
198 // vim: et sw=4 sts=4