144 lines
4.6 KiB
PHP
144 lines
4.6 KiB
PHP
<?php
|
|
|
|
// if want to implement error collecting here, we'll need to use some sort
|
|
// of global data (probably trigger_error) because it's impossible to pass
|
|
// $config or $context to the callback functions.
|
|
|
|
/**
|
|
* Handles referencing and derefencing character entities
|
|
*/
|
|
class HTMLPurifier_EntityParser
|
|
{
|
|
|
|
/**
|
|
* Reference to entity lookup table.
|
|
*/
|
|
protected $_entity_lookup;
|
|
|
|
/**
|
|
* Callback regex string for parsing entities.
|
|
*/
|
|
protected $_substituteEntitiesRegex =
|
|
'/&(?:[#]x([a-fA-F0-9]+)|[#]0*(\d+)|([A-Za-z_:][A-Za-z0-9.\-_:]*));?/';
|
|
// 1. hex 2. dec 3. string (XML style)
|
|
|
|
|
|
/**
|
|
* Decimal to parsed string conversion table for special entities.
|
|
*/
|
|
protected $_special_dec2str =
|
|
array(
|
|
34 => '"',
|
|
38 => '&',
|
|
39 => "'",
|
|
60 => '<',
|
|
62 => '>'
|
|
);
|
|
|
|
/**
|
|
* Stripped entity names to decimal conversion table for special entities.
|
|
*/
|
|
protected $_special_ent2dec =
|
|
array(
|
|
'quot' => 34,
|
|
'amp' => 38,
|
|
'lt' => 60,
|
|
'gt' => 62
|
|
);
|
|
|
|
/**
|
|
* Substitutes non-special entities with their parsed equivalents. Since
|
|
* running this whenever you have parsed character is t3h 5uck, we run
|
|
* it before everything else.
|
|
*
|
|
* @param $string String to have non-special entities parsed.
|
|
* @returns Parsed string.
|
|
*/
|
|
public function substituteNonSpecialEntities($string) {
|
|
// it will try to detect missing semicolons, but don't rely on it
|
|
return preg_replace_callback(
|
|
$this->_substituteEntitiesRegex,
|
|
array($this, 'nonSpecialEntityCallback'),
|
|
$string
|
|
);
|
|
}
|
|
|
|
/**
|
|
* Callback function for substituteNonSpecialEntities() that does the work.
|
|
*
|
|
* @param $matches PCRE matches array, with 0 the entire match, and
|
|
* either index 1, 2 or 3 set with a hex value, dec value,
|
|
* or string (respectively).
|
|
* @returns Replacement string.
|
|
*/
|
|
|
|
protected function nonSpecialEntityCallback($matches) {
|
|
// replaces all but big five
|
|
$entity = $matches[0];
|
|
$is_num = (@$matches[0][1] === '#');
|
|
if ($is_num) {
|
|
$is_hex = (@$entity[2] === 'x');
|
|
$code = $is_hex ? hexdec($matches[1]) : (int) $matches[2];
|
|
|
|
// abort for special characters
|
|
if (isset($this->_special_dec2str[$code])) return $entity;
|
|
|
|
return HTMLPurifier_Encoder::unichr($code);
|
|
} else {
|
|
if (isset($this->_special_ent2dec[$matches[3]])) return $entity;
|
|
if (!$this->_entity_lookup) {
|
|
$this->_entity_lookup = HTMLPurifier_EntityLookup::instance();
|
|
}
|
|
if (isset($this->_entity_lookup->table[$matches[3]])) {
|
|
return $this->_entity_lookup->table[$matches[3]];
|
|
} else {
|
|
return $entity;
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Substitutes only special entities with their parsed equivalents.
|
|
*
|
|
* @notice We try to avoid calling this function because otherwise, it
|
|
* would have to be called a lot (for every parsed section).
|
|
*
|
|
* @param $string String to have non-special entities parsed.
|
|
* @returns Parsed string.
|
|
*/
|
|
public function substituteSpecialEntities($string) {
|
|
return preg_replace_callback(
|
|
$this->_substituteEntitiesRegex,
|
|
array($this, 'specialEntityCallback'),
|
|
$string);
|
|
}
|
|
|
|
/**
|
|
* Callback function for substituteSpecialEntities() that does the work.
|
|
*
|
|
* This callback has same syntax as nonSpecialEntityCallback().
|
|
*
|
|
* @param $matches PCRE-style matches array, with 0 the entire match, and
|
|
* either index 1, 2 or 3 set with a hex value, dec value,
|
|
* or string (respectively).
|
|
* @returns Replacement string.
|
|
*/
|
|
protected function specialEntityCallback($matches) {
|
|
$entity = $matches[0];
|
|
$is_num = (@$matches[0][1] === '#');
|
|
if ($is_num) {
|
|
$is_hex = (@$entity[2] === 'x');
|
|
$int = $is_hex ? hexdec($matches[1]) : (int) $matches[2];
|
|
return isset($this->_special_dec2str[$int]) ?
|
|
$this->_special_dec2str[$int] :
|
|
$entity;
|
|
} else {
|
|
return isset($this->_special_ent2dec[$matches[3]]) ?
|
|
$this->_special_ent2dec[$matches[3]] :
|
|
$entity;
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
// vim: et sw=4 sts=4
|