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diff --git a/lib/htmlpurifier/library/HTMLPurifier/Strategy/MakeWellFormed.php b/lib/htmlpurifier/library/HTMLPurifier/Strategy/MakeWellFormed.php
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+++ b/lib/htmlpurifier/library/HTMLPurifier/Strategy/MakeWellFormed.php
@@ -0,0 +1,532 @@
+<?php
+
+/**
+ * Takes tokens makes them well-formed (balance end tags, etc.)
+ *
+ * Specification of the armor attributes this strategy uses:
+ *
+ * - MakeWellFormed_TagClosedError: This armor field is used to
+ * suppress tag closed errors for certain tokens [TagClosedSuppress],
+ * in particular, if a tag was generated automatically by HTML
+ * Purifier, we may rely on our infrastructure to close it for us
+ * and shouldn't report an error to the user [TagClosedAuto].
+ */
+class HTMLPurifier_Strategy_MakeWellFormed extends HTMLPurifier_Strategy
+{
+
+ /**
+ * Array stream of tokens being processed.
+ */
+ protected $tokens;
+
+ /**
+ * Current index in $tokens.
+ */
+ protected $t;
+
+ /**
+ * Current nesting of elements.
+ */
+ protected $stack;
+
+ /**
+ * Injectors active in this stream processing.
+ */
+ protected $injectors;
+
+ /**
+ * Current instance of HTMLPurifier_Config.
+ */
+ protected $config;
+
+ /**
+ * Current instance of HTMLPurifier_Context.
+ */
+ protected $context;
+
+ public function execute($tokens, $config, $context) {
+
+ $definition = $config->getHTMLDefinition();
+
+ // local variables
+ $generator = new HTMLPurifier_Generator($config, $context);
+ $escape_invalid_tags = $config->get('Core.EscapeInvalidTags');
+ // used for autoclose early abortion
+ $global_parent_allowed_elements = array();
+ if (isset($definition->info[$definition->info_parent])) {
+ // may be unset under testing circumstances
+ $global_parent_allowed_elements = $definition->info[$definition->info_parent]->child->getAllowedElements($config);
+ }
+ $e = $context->get('ErrorCollector', true);
+ $t = false; // token index
+ $i = false; // injector index
+ $token = false; // the current token
+ $reprocess = false; // whether or not to reprocess the same token
+ $stack = array();
+
+ // member variables
+ $this->stack =& $stack;
+ $this->t =& $t;
+ $this->tokens =& $tokens;
+ $this->config = $config;
+ $this->context = $context;
+
+ // context variables
+ $context->register('CurrentNesting', $stack);
+ $context->register('InputIndex', $t);
+ $context->register('InputTokens', $tokens);
+ $context->register('CurrentToken', $token);
+
+ // -- begin INJECTOR --
+
+ $this->injectors = array();
+
+ $injectors = $config->getBatch('AutoFormat');
+ $def_injectors = $definition->info_injector;
+ $custom_injectors = $injectors['Custom'];
+ unset($injectors['Custom']); // special case
+ foreach ($injectors as $injector => $b) {
+ // XXX: Fix with a legitimate lookup table of enabled filters
+ if (strpos($injector, '.') !== false) continue;
+ $injector = "HTMLPurifier_Injector_$injector";
+ if (!$b) continue;
+ $this->injectors[] = new $injector;
+ }
+ foreach ($def_injectors as $injector) {
+ // assumed to be objects
+ $this->injectors[] = $injector;
+ }
+ foreach ($custom_injectors as $injector) {
+ if (!$injector) continue;
+ if (is_string($injector)) {
+ $injector = "HTMLPurifier_Injector_$injector";
+ $injector = new $injector;
+ }
+ $this->injectors[] = $injector;
+ }
+
+ // give the injectors references to the definition and context
+ // variables for performance reasons
+ foreach ($this->injectors as $ix => $injector) {
+ $error = $injector->prepare($config, $context);
+ if (!$error) continue;
+ array_splice($this->injectors, $ix, 1); // rm the injector
+ trigger_error("Cannot enable {$injector->name} injector because $error is not allowed", E_USER_WARNING);
+ }
+
+ // -- end INJECTOR --
+
+ // a note on reprocessing:
+ // In order to reduce code duplication, whenever some code needs
+ // to make HTML changes in order to make things "correct", the
+ // new HTML gets sent through the purifier, regardless of its
+ // status. This means that if we add a start token, because it
+ // was totally necessary, we don't have to update nesting; we just
+ // punt ($reprocess = true; continue;) and it does that for us.
+
+ // isset is in loop because $tokens size changes during loop exec
+ for (
+ $t = 0;
+ $t == 0 || isset($tokens[$t - 1]);
+ // only increment if we don't need to reprocess
+ $reprocess ? $reprocess = false : $t++
+ ) {
+
+ // check for a rewind
+ if (is_int($i) && $i >= 0) {
+ // possibility: disable rewinding if the current token has a
+ // rewind set on it already. This would offer protection from
+ // infinite loop, but might hinder some advanced rewinding.
+ $rewind_to = $this->injectors[$i]->getRewind();
+ if (is_int($rewind_to) && $rewind_to < $t) {
+ if ($rewind_to < 0) $rewind_to = 0;
+ while ($t > $rewind_to) {
+ $t--;
+ $prev = $tokens[$t];
+ // indicate that other injectors should not process this token,
+ // but we need to reprocess it
+ unset($prev->skip[$i]);
+ $prev->rewind = $i;
+ if ($prev instanceof HTMLPurifier_Token_Start) array_pop($this->stack);
+ elseif ($prev instanceof HTMLPurifier_Token_End) $this->stack[] = $prev->start;
+ }
+ }
+ $i = false;
+ }
+
+ // handle case of document end
+ if (!isset($tokens[$t])) {
+ // kill processing if stack is empty
+ if (empty($this->stack)) break;
+
+ // peek
+ $top_nesting = array_pop($this->stack);
+ $this->stack[] = $top_nesting;
+
+ // send error [TagClosedSuppress]
+ if ($e && !isset($top_nesting->armor['MakeWellFormed_TagClosedError'])) {
+ $e->send(E_NOTICE, 'Strategy_MakeWellFormed: Tag closed by document end', $top_nesting);
+ }
+
+ // append, don't splice, since this is the end
+ $tokens[] = new HTMLPurifier_Token_End($top_nesting->name);
+
+ // punt!
+ $reprocess = true;
+ continue;
+ }
+
+ $token = $tokens[$t];
+
+ //echo '<br>'; printTokens($tokens, $t); printTokens($this->stack);
+ //flush();
+
+ // quick-check: if it's not a tag, no need to process
+ if (empty($token->is_tag)) {
+ if ($token instanceof HTMLPurifier_Token_Text) {
+ foreach ($this->injectors as $i => $injector) {
+ if (isset($token->skip[$i])) continue;
+ if ($token->rewind !== null && $token->rewind !== $i) continue;
+ $injector->handleText($token);
+ $this->processToken($token, $i);
+ $reprocess = true;
+ break;
+ }
+ }
+ // another possibility is a comment
+ continue;
+ }
+
+ if (isset($definition->info[$token->name])) {
+ $type = $definition->info[$token->name]->child->type;
+ } else {
+ $type = false; // Type is unknown, treat accordingly
+ }
+
+ // quick tag checks: anything that's *not* an end tag
+ $ok = false;
+ if ($type === 'empty' && $token instanceof HTMLPurifier_Token_Start) {
+ // claims to be a start tag but is empty
+ $token = new HTMLPurifier_Token_Empty($token->name, $token->attr, $token->line, $token->col, $token->armor);
+ $ok = true;
+ } elseif ($type && $type !== 'empty' && $token instanceof HTMLPurifier_Token_Empty) {
+ // claims to be empty but really is a start tag
+ $this->swap(new HTMLPurifier_Token_End($token->name));
+ $this->insertBefore(new HTMLPurifier_Token_Start($token->name, $token->attr, $token->line, $token->col, $token->armor));
+ // punt (since we had to modify the input stream in a non-trivial way)
+ $reprocess = true;
+ continue;
+ } elseif ($token instanceof HTMLPurifier_Token_Empty) {
+ // real empty token
+ $ok = true;
+ } elseif ($token instanceof HTMLPurifier_Token_Start) {
+ // start tag
+
+ // ...unless they also have to close their parent
+ if (!empty($this->stack)) {
+
+ // Performance note: you might think that it's rather
+ // inefficient, recalculating the autoclose information
+ // for every tag that a token closes (since when we
+ // do an autoclose, we push a new token into the
+ // stream and then /process/ that, before
+ // re-processing this token.) But this is
+ // necessary, because an injector can make an
+ // arbitrary transformations to the autoclosing
+ // tokens we introduce, so things may have changed
+ // in the meantime. Also, doing the inefficient thing is
+ // "easy" to reason about (for certain perverse definitions
+ // of "easy")
+
+ $parent = array_pop($this->stack);
+ $this->stack[] = $parent;
+
+ if (isset($definition->info[$parent->name])) {
+ $elements = $definition->info[$parent->name]->child->getAllowedElements($config);
+ $autoclose = !isset($elements[$token->name]);
+ } else {
+ $autoclose = false;
+ }
+
+ if ($autoclose && $definition->info[$token->name]->wrap) {
+ // Check if an element can be wrapped by another
+ // element to make it valid in a context (for
+ // example, <ul><ul> needs a <li> in between)
+ $wrapname = $definition->info[$token->name]->wrap;
+ $wrapdef = $definition->info[$wrapname];
+ $elements = $wrapdef->child->getAllowedElements($config);
+ $parent_elements = $definition->info[$parent->name]->child->getAllowedElements($config);
+ if (isset($elements[$token->name]) && isset($parent_elements[$wrapname])) {
+ $newtoken = new HTMLPurifier_Token_Start($wrapname);
+ $this->insertBefore($newtoken);
+ $reprocess = true;
+ continue;
+ }
+ }
+
+ $carryover = false;
+ if ($autoclose && $definition->info[$parent->name]->formatting) {
+ $carryover = true;
+ }
+
+ if ($autoclose) {
+ // check if this autoclose is doomed to fail
+ // (this rechecks $parent, which his harmless)
+ $autoclose_ok = isset($global_parent_allowed_elements[$token->name]);
+ if (!$autoclose_ok) {
+ foreach ($this->stack as $ancestor) {
+ $elements = $definition->info[$ancestor->name]->child->getAllowedElements($config);
+ if (isset($elements[$token->name])) {
+ $autoclose_ok = true;
+ break;
+ }
+ if ($definition->info[$token->name]->wrap) {
+ $wrapname = $definition->info[$token->name]->wrap;
+ $wrapdef = $definition->info[$wrapname];
+ $wrap_elements = $wrapdef->child->getAllowedElements($config);
+ if (isset($wrap_elements[$token->name]) && isset($elements[$wrapname])) {
+ $autoclose_ok = true;
+ break;
+ }
+ }
+ }
+ }
+ if ($autoclose_ok) {
+ // errors need to be updated
+ $new_token = new HTMLPurifier_Token_End($parent->name);
+ $new_token->start = $parent;
+ if ($carryover) {
+ $element = clone $parent;
+ // [TagClosedAuto]
+ $element->armor['MakeWellFormed_TagClosedError'] = true;
+ $element->carryover = true;
+ $this->processToken(array($new_token, $token, $element));
+ } else {
+ $this->insertBefore($new_token);
+ }
+ // [TagClosedSuppress]
+ if ($e && !isset($parent->armor['MakeWellFormed_TagClosedError'])) {
+ if (!$carryover) {
+ $e->send(E_NOTICE, 'Strategy_MakeWellFormed: Tag auto closed', $parent);
+ } else {
+ $e->send(E_NOTICE, 'Strategy_MakeWellFormed: Tag carryover', $parent);
+ }
+ }
+ } else {
+ $this->remove();
+ }
+ $reprocess = true;
+ continue;
+ }
+
+ }
+ $ok = true;
+ }
+
+ if ($ok) {
+ foreach ($this->injectors as $i => $injector) {
+ if (isset($token->skip[$i])) continue;
+ if ($token->rewind !== null && $token->rewind !== $i) continue;
+ $injector->handleElement($token);
+ $this->processToken($token, $i);
+ $reprocess = true;
+ break;
+ }
+ if (!$reprocess) {
+ // ah, nothing interesting happened; do normal processing
+ $this->swap($token);
+ if ($token instanceof HTMLPurifier_Token_Start) {
+ $this->stack[] = $token;
+ } elseif ($token instanceof HTMLPurifier_Token_End) {
+ throw new HTMLPurifier_Exception('Improper handling of end tag in start code; possible error in MakeWellFormed');
+ }
+ }
+ continue;
+ }
+
+ // sanity check: we should be dealing with a closing tag
+ if (!$token instanceof HTMLPurifier_Token_End) {
+ throw new HTMLPurifier_Exception('Unaccounted for tag token in input stream, bug in HTML Purifier');
+ }
+
+ // make sure that we have something open
+ if (empty($this->stack)) {
+ if ($escape_invalid_tags) {
+ if ($e) $e->send(E_WARNING, 'Strategy_MakeWellFormed: Unnecessary end tag to text');
+ $this->swap(new HTMLPurifier_Token_Text(
+ $generator->generateFromToken($token)
+ ));
+ } else {
+ $this->remove();
+ if ($e) $e->send(E_WARNING, 'Strategy_MakeWellFormed: Unnecessary end tag removed');
+ }
+ $reprocess = true;
+ continue;
+ }
+
+ // first, check for the simplest case: everything closes neatly.
+ // Eventually, everything passes through here; if there are problems
+ // we modify the input stream accordingly and then punt, so that
+ // the tokens get processed again.
+ $current_parent = array_pop($this->stack);
+ if ($current_parent->name == $token->name) {
+ $token->start = $current_parent;
+ foreach ($this->injectors as $i => $injector) {
+ if (isset($token->skip[$i])) continue;
+ if ($token->rewind !== null && $token->rewind !== $i) continue;
+ $injector->handleEnd($token);
+ $this->processToken($token, $i);
+ $this->stack[] = $current_parent;
+ $reprocess = true;
+ break;
+ }
+ continue;
+ }
+
+ // okay, so we're trying to close the wrong tag
+
+ // undo the pop previous pop
+ $this->stack[] = $current_parent;
+
+ // scroll back the entire nest, trying to find our tag.
+ // (feature could be to specify how far you'd like to go)
+ $size = count($this->stack);
+ // -2 because -1 is the last element, but we already checked that
+ $skipped_tags = false;
+ for ($j = $size - 2; $j >= 0; $j--) {
+ if ($this->stack[$j]->name == $token->name) {
+ $skipped_tags = array_slice($this->stack, $j);
+ break;
+ }
+ }
+
+ // we didn't find the tag, so remove
+ if ($skipped_tags === false) {
+ if ($escape_invalid_tags) {
+ $this->swap(new HTMLPurifier_Token_Text(
+ $generator->generateFromToken($token)
+ ));
+ if ($e) $e->send(E_WARNING, 'Strategy_MakeWellFormed: Stray end tag to text');
+ } else {
+ $this->remove();
+ if ($e) $e->send(E_WARNING, 'Strategy_MakeWellFormed: Stray end tag removed');
+ }
+ $reprocess = true;
+ continue;
+ }
+
+ // do errors, in REVERSE $j order: a,b,c with </a></b></c>
+ $c = count($skipped_tags);
+ if ($e) {
+ for ($j = $c - 1; $j > 0; $j--) {
+ // notice we exclude $j == 0, i.e. the current ending tag, from
+ // the errors... [TagClosedSuppress]
+ if (!isset($skipped_tags[$j]->armor['MakeWellFormed_TagClosedError'])) {
+ $e->send(E_NOTICE, 'Strategy_MakeWellFormed: Tag closed by element end', $skipped_tags[$j]);
+ }
+ }
+ }
+
+ // insert tags, in FORWARD $j order: c,b,a with </a></b></c>
+ $replace = array($token);
+ for ($j = 1; $j < $c; $j++) {
+ // ...as well as from the insertions
+ $new_token = new HTMLPurifier_Token_End($skipped_tags[$j]->name);
+ $new_token->start = $skipped_tags[$j];
+ array_unshift($replace, $new_token);
+ if (isset($definition->info[$new_token->name]) && $definition->info[$new_token->name]->formatting) {
+ // [TagClosedAuto]
+ $element = clone $skipped_tags[$j];
+ $element->carryover = true;
+ $element->armor['MakeWellFormed_TagClosedError'] = true;
+ $replace[] = $element;
+ }
+ }
+ $this->processToken($replace);
+ $reprocess = true;
+ continue;
+ }
+
+ $context->destroy('CurrentNesting');
+ $context->destroy('InputTokens');
+ $context->destroy('InputIndex');
+ $context->destroy('CurrentToken');
+
+ unset($this->injectors, $this->stack, $this->tokens, $this->t);
+ return $tokens;
+ }
+
+ /**
+ * Processes arbitrary token values for complicated substitution patterns.
+ * In general:
+ *
+ * If $token is an array, it is a list of tokens to substitute for the
+ * current token. These tokens then get individually processed. If there
+ * is a leading integer in the list, that integer determines how many
+ * tokens from the stream should be removed.
+ *
+ * If $token is a regular token, it is swapped with the current token.
+ *
+ * If $token is false, the current token is deleted.
+ *
+ * If $token is an integer, that number of tokens (with the first token
+ * being the current one) will be deleted.
+ *
+ * @param $token Token substitution value
+ * @param $injector Injector that performed the substitution; default is if
+ * this is not an injector related operation.
+ */
+ protected function processToken($token, $injector = -1) {
+
+ // normalize forms of token
+ if (is_object($token)) $token = array(1, $token);
+ if (is_int($token)) $token = array($token);
+ if ($token === false) $token = array(1);
+ if (!is_array($token)) throw new HTMLPurifier_Exception('Invalid token type from injector');
+ if (!is_int($token[0])) array_unshift($token, 1);
+ if ($token[0] === 0) throw new HTMLPurifier_Exception('Deleting zero tokens is not valid');
+
+ // $token is now an array with the following form:
+ // array(number nodes to delete, new node 1, new node 2, ...)
+
+ $delete = array_shift($token);
+ $old = array_splice($this->tokens, $this->t, $delete, $token);
+
+ if ($injector > -1) {
+ // determine appropriate skips
+ $oldskip = isset($old[0]) ? $old[0]->skip : array();
+ foreach ($token as $object) {
+ $object->skip = $oldskip;
+ $object->skip[$injector] = true;
+ }
+ }
+
+ }
+
+ /**
+ * Inserts a token before the current token. Cursor now points to
+ * this token. You must reprocess after this.
+ */
+ private function insertBefore($token) {
+ array_splice($this->tokens, $this->t, 0, array($token));
+ }
+
+ /**
+ * Removes current token. Cursor now points to new token occupying previously
+ * occupied space. You must reprocess after this.
+ */
+ private function remove() {
+ array_splice($this->tokens, $this->t, 1);
+ }
+
+ /**
+ * Swap current token with new token. Cursor points to new token (no
+ * change). You must reprocess after this.
+ */
+ private function swap($token) {
+ $this->tokens[$this->t] = $token;
+ }
+
+}
+
+// vim: et sw=4 sts=4
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-30 19:00:33 +0000