mirror of
https://github.com/ezyang/htmlpurifier.git
synced 2024-12-23 08:51:53 +00:00
9a35dfa6b9
git-svn-id: http://htmlpurifier.org/svnroot/htmlpurifier/trunk@258 48356398-32a2-884e-a903-53898d9a118a
255 lines
8.5 KiB
PHP
255 lines
8.5 KiB
PHP
<?php
|
|
|
|
require_once 'HTMLPurifier/Token.php';
|
|
|
|
HTMLPurifier_ConfigDef::define(
|
|
'Core', 'AcceptFullDocuments', true,
|
|
'This parameter determines whether or not the filter should accept full '.
|
|
'HTML documents, not just HTML fragments. When on, it will '.
|
|
'drop all sections except the content between body. Depending on '.
|
|
'the implementation in use, this may speed up document parse times.'
|
|
);
|
|
|
|
/**
|
|
* Forgivingly lexes HTML (SGML-style) markup into tokens.
|
|
*
|
|
* A lexer parses a string of SGML-style markup and converts them into
|
|
* corresponding tokens. It doesn't check for well-formedness, although its
|
|
* internal mechanism may make this automatic (such as the case of
|
|
* HTMLPurifier_Lexer_DOMLex). There are several implementations to choose
|
|
* from.
|
|
*
|
|
* A lexer is HTML-oriented: it might work with XML, but it's not
|
|
* recommended, as we adhere to a subset of the specification for optimization
|
|
* reasons.
|
|
*
|
|
* This class should not be directly instantiated, but you may use create() to
|
|
* retrieve a default copy of the lexer. Being a supertype, this class
|
|
* does not actually define any implementation, but offers commonly used
|
|
* convenience functions for subclasses.
|
|
*
|
|
* @note The unit tests will instantiate this class for testing purposes, as
|
|
* many of the utility functions require a class to be instantiated.
|
|
* Be careful when porting this class to PHP 5.
|
|
*
|
|
* @par
|
|
*
|
|
* @note
|
|
* We use tokens rather than create a DOM representation because DOM would:
|
|
*
|
|
* @par
|
|
* -# Require more processing power to create,
|
|
* -# Require recursion to iterate,
|
|
* -# Must be compatible with PHP 5's DOM (otherwise duplication),
|
|
* -# Has the entire document structure (html and body not needed), and
|
|
* -# Has unknown readability improvement.
|
|
*
|
|
* @par
|
|
* What the last item means is that the functions for manipulating tokens are
|
|
* already fairly compact, and when well-commented, more abstraction may not
|
|
* be needed.
|
|
*
|
|
* @see HTMLPurifier_Token
|
|
*/
|
|
class HTMLPurifier_Lexer
|
|
{
|
|
|
|
/**
|
|
* Lexes an HTML string into tokens.
|
|
*
|
|
* @param $string String HTML.
|
|
* @return HTMLPurifier_Token array representation of HTML.
|
|
*/
|
|
function tokenizeHTML($string, $config = null) {
|
|
trigger_error('Call to abstract class', E_USER_ERROR);
|
|
}
|
|
|
|
/**
|
|
* Retrieves or sets the default Lexer as a Prototype Factory.
|
|
*
|
|
* Depending on what PHP version you are running, the abstract base
|
|
* Lexer class will determine which concrete Lexer is best for you:
|
|
* HTMLPurifier_Lexer_DirectLex for PHP 4, and HTMLPurifier_Lexer_DOMLex
|
|
* for PHP 5 and beyond.
|
|
*
|
|
* Passing the optional prototype lexer parameter will override the
|
|
* default with your own implementation. A copy/reference of the prototype
|
|
* lexer will now be returned when you request a new lexer.
|
|
*
|
|
* @note
|
|
* Though it is possible to call this factory method from subclasses,
|
|
* such usage is not recommended.
|
|
*
|
|
* @param $prototype Optional prototype lexer.
|
|
* @return Concrete lexer.
|
|
*/
|
|
function create($prototype = null) {
|
|
// we don't really care if it's a reference or a copy
|
|
static $lexer = null;
|
|
if ($prototype) {
|
|
$lexer = $prototype;
|
|
}
|
|
if (empty($lexer)) {
|
|
if (version_compare(PHP_VERSION, '5', '>=')) {
|
|
require_once 'HTMLPurifier/Lexer/DOMLex.php';
|
|
$lexer = new HTMLPurifier_Lexer_DOMLex();
|
|
} else {
|
|
require_once 'HTMLPurifier/Lexer/DirectLex.php';
|
|
$lexer = new HTMLPurifier_Lexer_DirectLex();
|
|
}
|
|
}
|
|
return $lexer;
|
|
}
|
|
|
|
/**
|
|
* Decimal to parsed string conversion table for special entities.
|
|
* @protected
|
|
*/
|
|
var $_special_dec2str =
|
|
array(
|
|
34 => '"',
|
|
38 => '&',
|
|
39 => "'",
|
|
60 => '<',
|
|
62 => '>'
|
|
);
|
|
|
|
/**
|
|
* Stripped entity names to decimal conversion table for special entities.
|
|
* @protected
|
|
*/
|
|
var $_special_ent2dec =
|
|
array(
|
|
'quot' => 34,
|
|
'amp' => 38,
|
|
'lt' => 60,
|
|
'gt' => 62
|
|
);
|
|
|
|
/**
|
|
* Most common entity to raw value conversion table for special entities.
|
|
* @protected
|
|
*/
|
|
var $_special_entity2str =
|
|
array(
|
|
'"' => '"',
|
|
'&' => '&',
|
|
'<' => '<',
|
|
'>' => '>',
|
|
''' => "'",
|
|
''' => "'",
|
|
''' => "'"
|
|
);
|
|
|
|
/**
|
|
* Callback regex string for parsing entities.
|
|
* @protected
|
|
*/
|
|
var $_substituteEntitiesRegex =
|
|
'/&(?:[#]x([a-fA-F0-9]+)|[#]0*(\d+)|([A-Za-z]+));?/';
|
|
// 1. hex 2. dec 3. string
|
|
|
|
/**
|
|
* 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.
|
|
*
|
|
* @protected
|
|
* @param $string String to have non-special entities parsed.
|
|
* @returns Parsed string.
|
|
*/
|
|
function substituteNonSpecialEntities($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.
|
|
*
|
|
* @warning Though this is public in order to let the callback happen,
|
|
* calling it directly is not recommended.
|
|
* @param $matches PCRE matches array, with 0 the entire match, and
|
|
* either index 1, 2 or 3 set with a hex value, dec value,
|
|
* or string (respectively).
|
|
* @returns Replacement string.
|
|
* @todo Implement string translations
|
|
*/
|
|
function nonSpecialEntityCallback($matches) {
|
|
// replaces all but big five
|
|
$entity = $matches[0];
|
|
$is_num = (@$matches[0][1] === '#');
|
|
if ($is_num) {
|
|
$is_hex = (@$entity[2] === 'x');
|
|
$int = $is_hex ? hexdec($matches[1]) : (int) $matches[2];
|
|
if (isset($this->_special_dec2str[$int])) return $entity;
|
|
return chr($int);
|
|
} else {
|
|
if (isset($this->_special_ent2dec[$matches[3]])) return $entity;
|
|
if (!$this->_entity_lookup) {
|
|
require_once 'HTMLPurifier/EntityLookup.php';
|
|
$this->_entity_lookup = HTMLPurifier_EntityLookup::instance();
|
|
}
|
|
if (isset($this->_entity_lookup->table[$matches[3]])) {
|
|
return $this->_entity_lookup->table[$matches[3]];
|
|
} else {
|
|
return $entity;
|
|
}
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Contains a copy of the EntityLookup table.
|
|
* @protected
|
|
*/
|
|
var $_entity_lookup;
|
|
|
|
/**
|
|
* Translates CDATA sections into regular sections (through escaping).
|
|
*
|
|
* @protected
|
|
* @param $string HTML string to process.
|
|
* @returns HTML with CDATA sections escaped.
|
|
*/
|
|
function escapeCDATA($string) {
|
|
return preg_replace_callback(
|
|
'/<!\[CDATA\[(.+?)\]\]>/',
|
|
array('HTMLPurifier_Lexer', 'CDATACallback'),
|
|
$string
|
|
);
|
|
}
|
|
|
|
/**
|
|
* Callback function for escapeCDATA() that does the work.
|
|
*
|
|
* @warning Though this is public in order to let the callback happen,
|
|
* calling it directly is not recommended.
|
|
* @params $matches PCRE matches array, with index 0 the entire match
|
|
* and 1 the inside of the CDATA section.
|
|
* @returns Escaped internals of the CDATA section.
|
|
*/
|
|
function CDATACallback($matches) {
|
|
// not exactly sure why the character set is needed, but whatever
|
|
return htmlspecialchars($matches[1], ENT_COMPAT, 'UTF-8');
|
|
}
|
|
|
|
/**
|
|
* Takes a string of HTML (fragment or document) and returns the content
|
|
*/
|
|
function extractBody($html, $return_bool = false) {
|
|
$matches = array();
|
|
$result = preg_match('!<body[^>]*>(.+?)</body>!is', $html, $matches);
|
|
if ($return_bool) return $result;
|
|
if ($result) {
|
|
return $matches[1];
|
|
} else {
|
|
return $html;
|
|
}
|
|
}
|
|
|
|
}
|
|
|
|
?>
|