aboutsummaryrefslogtreecommitdiffstats
path: root/lib/htmlpurifier/library/HTMLPurifier/Lexer/DOMLex.php
diff options
context:
space:
mode:
authorfriendica <info@friendica.com>2012-05-12 17:57:41 -0700
committerfriendica <info@friendica.com>2012-07-18 20:40:31 +1000
commit7a40f4354b32809af3d0cfd6e3af0eda02ab0e0a (patch)
treea9c3d91209cff770bb4b613b1b95e61a7bbc5a2b /lib/htmlpurifier/library/HTMLPurifier/Lexer/DOMLex.php
parentcd727cb26b78a1dade09d510b071446898477356 (diff)
downloadvolse-hubzilla-7a40f4354b32809af3d0cfd6e3af0eda02ab0e0a.tar.gz
volse-hubzilla-7a40f4354b32809af3d0cfd6e3af0eda02ab0e0a.tar.bz2
volse-hubzilla-7a40f4354b32809af3d0cfd6e3af0eda02ab0e0a.zip
some important stuff we'll need
Diffstat (limited to 'lib/htmlpurifier/library/HTMLPurifier/Lexer/DOMLex.php')
-rw-r--r--lib/htmlpurifier/library/HTMLPurifier/Lexer/DOMLex.php243
1 files changed, 243 insertions, 0 deletions
diff --git a/lib/htmlpurifier/library/HTMLPurifier/Lexer/DOMLex.php b/lib/htmlpurifier/library/HTMLPurifier/Lexer/DOMLex.php
new file mode 100644
index 000000000..82f377450
--- /dev/null
+++ b/lib/htmlpurifier/library/HTMLPurifier/Lexer/DOMLex.php
@@ -0,0 +1,243 @@
+<?php
+
+/**
+ * Parser that uses PHP 5's DOM extension (part of the core).
+ *
+ * In PHP 5, the DOM XML extension was revamped into DOM and added to the core.
+ * It gives us a forgiving HTML parser, which we use to transform the HTML
+ * into a DOM, and then into the tokens. It is blazingly fast (for large
+ * documents, it performs twenty times faster than
+ * HTMLPurifier_Lexer_DirectLex,and is the default choice for PHP 5.
+ *
+ * @note Any empty elements will have empty tokens associated with them, even if
+ * this is prohibited by the spec. This is cannot be fixed until the spec
+ * comes into play.
+ *
+ * @note PHP's DOM extension does not actually parse any entities, we use
+ * our own function to do that.
+ *
+ * @warning DOM tends to drop whitespace, which may wreak havoc on indenting.
+ * If this is a huge problem, due to the fact that HTML is hand
+ * edited and you are unable to get a parser cache that caches the
+ * the output of HTML Purifier while keeping the original HTML lying
+ * around, you may want to run Tidy on the resulting output or use
+ * HTMLPurifier_DirectLex
+ */
+
+class HTMLPurifier_Lexer_DOMLex extends HTMLPurifier_Lexer
+{
+
+ private $factory;
+
+ public function __construct() {
+ // setup the factory
+ parent::__construct();
+ $this->factory = new HTMLPurifier_TokenFactory();
+ }
+
+ public function tokenizeHTML($html, $config, $context) {
+
+ $html = $this->normalize($html, $config, $context);
+
+ // attempt to armor stray angled brackets that cannot possibly
+ // form tags and thus are probably being used as emoticons
+ if ($config->get('Core.AggressivelyFixLt')) {
+ $char = '[^a-z!\/]';
+ $comment = "/<!--(.*?)(-->|\z)/is";
+ $html = preg_replace_callback($comment, array($this, 'callbackArmorCommentEntities'), $html);
+ do {
+ $old = $html;
+ $html = preg_replace("/<($char)/i", '&lt;\\1', $html);
+ } while ($html !== $old);
+ $html = preg_replace_callback($comment, array($this, 'callbackUndoCommentSubst'), $html); // fix comments
+ }
+
+ // preprocess html, essential for UTF-8
+ $html = $this->wrapHTML($html, $config, $context);
+
+ $doc = new DOMDocument();
+ $doc->encoding = 'UTF-8'; // theoretically, the above has this covered
+
+ set_error_handler(array($this, 'muteErrorHandler'));
+ $doc->loadHTML($html);
+ restore_error_handler();
+
+ $tokens = array();
+ $this->tokenizeDOM(
+ $doc->getElementsByTagName('html')->item(0)-> // <html>
+ getElementsByTagName('body')->item(0)-> // <body>
+ getElementsByTagName('div')->item(0) // <div>
+ , $tokens);
+ return $tokens;
+ }
+
+ /**
+ * Iterative function that tokenizes a node, putting it into an accumulator.
+ * To iterate is human, to recurse divine - L. Peter Deutsch
+ * @param $node DOMNode to be tokenized.
+ * @param $tokens Array-list of already tokenized tokens.
+ * @returns Tokens of node appended to previously passed tokens.
+ */
+ protected function tokenizeDOM($node, &$tokens) {
+
+ $level = 0;
+ $nodes = array($level => array($node));
+ $closingNodes = array();
+ do {
+ while (!empty($nodes[$level])) {
+ $node = array_shift($nodes[$level]); // FIFO
+ $collect = $level > 0 ? true : false;
+ $needEndingTag = $this->createStartNode($node, $tokens, $collect);
+ if ($needEndingTag) {
+ $closingNodes[$level][] = $node;
+ }
+ if ($node->childNodes && $node->childNodes->length) {
+ $level++;
+ $nodes[$level] = array();
+ foreach ($node->childNodes as $childNode) {
+ array_push($nodes[$level], $childNode);
+ }
+ }
+ }
+ $level--;
+ if ($level && isset($closingNodes[$level])) {
+ while($node = array_pop($closingNodes[$level])) {
+ $this->createEndNode($node, $tokens);
+ }
+ }
+ } while ($level > 0);
+ }
+
+ /**
+ * @param $node DOMNode to be tokenized.
+ * @param $tokens Array-list of already tokenized tokens.
+ * @param $collect Says whether or start and close are collected, set to
+ * false at first recursion because it's the implicit DIV
+ * tag you're dealing with.
+ * @returns bool if the token needs an endtoken
+ */
+ protected function createStartNode($node, &$tokens, $collect) {
+ // intercept non element nodes. WE MUST catch all of them,
+ // but we're not getting the character reference nodes because
+ // those should have been preprocessed
+ if ($node->nodeType === XML_TEXT_NODE) {
+ $tokens[] = $this->factory->createText($node->data);
+ return false;
+ } elseif ($node->nodeType === XML_CDATA_SECTION_NODE) {
+ // undo libxml's special treatment of <script> and <style> tags
+ $last = end($tokens);
+ $data = $node->data;
+ // (note $node->tagname is already normalized)
+ if ($last instanceof HTMLPurifier_Token_Start && ($last->name == 'script' || $last->name == 'style')) {
+ $new_data = trim($data);
+ if (substr($new_data, 0, 4) === '<!--') {
+ $data = substr($new_data, 4);
+ if (substr($data, -3) === '-->') {
+ $data = substr($data, 0, -3);
+ } else {
+ // Highly suspicious! Not sure what to do...
+ }
+ }
+ }
+ $tokens[] = $this->factory->createText($this->parseData($data));
+ return false;
+ } elseif ($node->nodeType === XML_COMMENT_NODE) {
+ // this is code is only invoked for comments in script/style in versions
+ // of libxml pre-2.6.28 (regular comments, of course, are still
+ // handled regularly)
+ $tokens[] = $this->factory->createComment($node->data);
+ return false;
+ } elseif (
+ // not-well tested: there may be other nodes we have to grab
+ $node->nodeType !== XML_ELEMENT_NODE
+ ) {
+ return false;
+ }
+
+ $attr = $node->hasAttributes() ? $this->transformAttrToAssoc($node->attributes) : array();
+
+ // We still have to make sure that the element actually IS empty
+ if (!$node->childNodes->length) {
+ if ($collect) {
+ $tokens[] = $this->factory->createEmpty($node->tagName, $attr);
+ }
+ return false;
+ } else {
+ if ($collect) {
+ $tokens[] = $this->factory->createStart(
+ $tag_name = $node->tagName, // somehow, it get's dropped
+ $attr
+ );
+ }
+ return true;
+ }
+ }
+
+ protected function createEndNode($node, &$tokens) {
+ $tokens[] = $this->factory->createEnd($node->tagName);
+ }
+
+
+ /**
+ * Converts a DOMNamedNodeMap of DOMAttr objects into an assoc array.
+ *
+ * @param $attribute_list DOMNamedNodeMap of DOMAttr objects.
+ * @returns Associative array of attributes.
+ */
+ protected function transformAttrToAssoc($node_map) {
+ // NamedNodeMap is documented very well, so we're using undocumented
+ // features, namely, the fact that it implements Iterator and
+ // has a ->length attribute
+ if ($node_map->length === 0) return array();
+ $array = array();
+ foreach ($node_map as $attr) {
+ $array[$attr->name] = $attr->value;
+ }
+ return $array;
+ }
+
+ /**
+ * An error handler that mutes all errors
+ */
+ public function muteErrorHandler($errno, $errstr) {}
+
+ /**
+ * Callback function for undoing escaping of stray angled brackets
+ * in comments
+ */
+ public function callbackUndoCommentSubst($matches) {
+ return '<!--' . strtr($matches[1], array('&amp;'=>'&','&lt;'=>'<')) . $matches[2];
+ }
+
+ /**
+ * Callback function that entity-izes ampersands in comments so that
+ * callbackUndoCommentSubst doesn't clobber them
+ */
+ public function callbackArmorCommentEntities($matches) {
+ return '<!--' . str_replace('&', '&amp;', $matches[1]) . $matches[2];
+ }
+
+ /**
+ * Wraps an HTML fragment in the necessary HTML
+ */
+ protected function wrapHTML($html, $config, $context) {
+ $def = $config->getDefinition('HTML');
+ $ret = '';
+
+ if (!empty($def->doctype->dtdPublic) || !empty($def->doctype->dtdSystem)) {
+ $ret .= '<!DOCTYPE html ';
+ if (!empty($def->doctype->dtdPublic)) $ret .= 'PUBLIC "' . $def->doctype->dtdPublic . '" ';
+ if (!empty($def->doctype->dtdSystem)) $ret .= '"' . $def->doctype->dtdSystem . '" ';
+ $ret .= '>';
+ }
+
+ $ret .= '<html><head>';
+ $ret .= '<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />';
+ // No protection if $html contains a stray </div>!
+ $ret .= '</head><body><div>'.$html.'</div></body></html>';
+ return $ret;
+ }
+
+}
+
+// vim: et sw=4 sts=4
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-04 10:37:54 +0000