diff options
Diffstat (limited to 'library/HTMLPurifier/Strategy/MakeWellFormed.php')
| -rw-r--r-- | library/HTMLPurifier/Strategy/MakeWellFormed.php | 379 |
1 files changed, 252 insertions, 127 deletions
diff --git a/library/HTMLPurifier/Strategy/MakeWellFormed.php b/library/HTMLPurifier/Strategy/MakeWellFormed.php index c73658400..e389e0011 100644 --- a/library/HTMLPurifier/Strategy/MakeWellFormed.php +++ b/library/HTMLPurifier/Strategy/MakeWellFormed.php @@ -2,66 +2,97 @@ /** * 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. + * @type HTMLPurifier_Token[] */ protected $tokens; /** - * Current index in $tokens. + * Current token. + * @type HTMLPurifier_Token */ - protected $t; + protected $token; + + /** + * Zipper managing the true state. + * @type HTMLPurifier_Zipper + */ + protected $zipper; /** * Current nesting of elements. + * @type array */ protected $stack; /** * Injectors active in this stream processing. + * @type HTMLPurifier_Injector[] */ protected $injectors; /** * Current instance of HTMLPurifier_Config. + * @type HTMLPurifier_Config */ protected $config; /** * Current instance of HTMLPurifier_Context. + * @type HTMLPurifier_Context */ protected $context; - public function execute($tokens, $config, $context) { - + /** + * @param HTMLPurifier_Token[] $tokens + * @param HTMLPurifier_Config $config + * @param HTMLPurifier_Context $context + * @return HTMLPurifier_Token[] + * @throws HTMLPurifier_Exception + */ + public function execute($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 = $definition->info_parent_def->child->getAllowedElements($config); $e = $context->get('ErrorCollector', true); - $t = false; // token index $i = false; // injector index - $token = false; // the current token - $reprocess = false; // whether or not to reprocess the same token + list($zipper, $token) = HTMLPurifier_Zipper::fromArray($tokens); + if ($token === NULL) { + return array(); + } + $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->stack =& $stack; + $this->tokens =& $tokens; + $this->token =& $token; + $this->zipper =& $zipper; + $this->config = $config; $this->context = $context; // context variables $context->register('CurrentNesting', $stack); - $context->register('InputIndex', $t); - $context->register('InputTokens', $tokens); - $context->register('CurrentToken', $token); + $context->register('InputZipper', $zipper); + $context->register('CurrentToken', $token); // -- begin INJECTOR -- @@ -73,9 +104,13 @@ class HTMLPurifier_Strategy_MakeWellFormed extends HTMLPurifier_Strategy unset($injectors['Custom']); // special case foreach ($injectors as $injector => $b) { // XXX: Fix with a legitimate lookup table of enabled filters - if (strpos($injector, '.') !== false) continue; + if (strpos($injector, '.') !== false) { + continue; + } $injector = "HTMLPurifier_Injector_$injector"; - if (!$b) continue; + if (!$b) { + continue; + } $this->injectors[] = new $injector; } foreach ($def_injectors as $injector) { @@ -83,7 +118,9 @@ class HTMLPurifier_Strategy_MakeWellFormed extends HTMLPurifier_Strategy $this->injectors[] = $injector; } foreach ($custom_injectors as $injector) { - if (!$injector) continue; + if (!$injector) { + continue; + } if (is_string($injector)) { $injector = "HTMLPurifier_Injector_$injector"; $injector = new $injector; @@ -95,14 +132,16 @@ class HTMLPurifier_Strategy_MakeWellFormed extends HTMLPurifier_Strategy // variables for performance reasons foreach ($this->injectors as $ix => $injector) { $error = $injector->prepare($config, $context); - if (!$error) continue; + if (!$error) { + continue; + } array_splice($this->injectors, $ix, 1); // rm the injector trigger_error("Cannot enable {$injector->name} injector because $error is not allowed", E_USER_WARNING); } // -- end INJECTOR -- - // a note on punting: + // a note on reprocessing: // In order to reduce code duplication, whenever some code needs // to make HTML changes in order to make things "correct", the // new HTML gets sent through the purifier, regardless of its @@ -111,70 +150,75 @@ class HTMLPurifier_Strategy_MakeWellFormed extends HTMLPurifier_Strategy // punt ($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++ - ) { + for (;; + // only increment if we don't need to reprocess + $reprocess ? $reprocess = false : $token = $zipper->next($token)) { // check for a rewind - if (is_int($i) && $i >= 0) { + if (is_int($i)) { // 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]; + $rewind_offset = $this->injectors[$i]->getRewindOffset(); + if (is_int($rewind_offset)) { + for ($j = 0; $j < $rewind_offset; $j++) { + if (empty($zipper->front)) break; + $token = $zipper->prev($token); // 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[] = $prev->start; + unset($token->skip[$i]); + $token->rewind = $i; + if ($token instanceof HTMLPurifier_Token_Start) { + array_pop($this->stack); + } elseif ($token instanceof HTMLPurifier_Token_End) { + $this->stack[] = $token->start; + } } } $i = false; } // handle case of document end - if (!isset($tokens[$t])) { + if ($token === NULL) { // kill processing if stack is empty - if (empty($this->stack)) break; + if (empty($this->stack)) { + break; + } // peek $top_nesting = array_pop($this->stack); $this->stack[] = $top_nesting; - // send error + // send error [TagClosedSuppress] if ($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); + $token = new HTMLPurifier_Token_End($top_nesting->name); // punt! $reprocess = true; continue; } - $token = $tokens[$t]; - - //echo '<br>'; printTokens($tokens, $t); printTokens($this->stack); + //echo '<br>'; printZipper($zipper, $token);//printTokens($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, $i); + if (isset($token->skip[$i])) { + continue; + } + if ($token->rewind !== null && $token->rewind !== $i) { + continue; + } + // XXX fuckup + $r = $token; + $injector->handleText($r); + $token = $this->processToken($r, $i); $reprocess = true; break; } @@ -193,12 +237,22 @@ class HTMLPurifier_Strategy_MakeWellFormed extends HTMLPurifier_Strategy $ok = false; if ($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 = 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)); + // NB: this assignment is required + $old_token = $token; + $token = new HTMLPurifier_Token_End($token->name); + $token = $this->insertBefore( + new HTMLPurifier_Token_Start($old_token->name, $old_token->attr, $old_token->line, $old_token->col, $old_token->armor) + ); // punt (since we had to modify the input stream in a non-trivial way) $reprocess = true; continue; @@ -211,55 +265,96 @@ class HTMLPurifier_Strategy_MakeWellFormed extends HTMLPurifier_Strategy // ...unless they also have to close their parent if (!empty($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; + $parent_def = null; + $parent_elements = null; + $autoclose = false; if (isset($definition->info[$parent->name])) { - $elements = $definition->info[$parent->name]->child->getAllowedElements($config); - $autoclose = !isset($elements[$token->name]); - } else { - $autoclose = false; + $parent_def = $definition->info[$parent->name]; + $parent_elements = $parent_def->child->getAllowedElements($config); + $autoclose = !isset($parent_elements[$token->name]); } if ($autoclose && $definition->info[$token->name]->wrap) { - // Check if an element can be wrapped by another - // element to make it valid in a context (for + // 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); + $token = $this->insertBefore($newtoken); $reprocess = true; continue; } } $carryover = false; - if ($autoclose && $definition->info[$parent->name]->formatting) { + if ($autoclose && $parent_def->formatting) { $carryover = true; } if ($autoclose) { - // errors need to be updated - $new_token = new HTMLPurifier_Token_End($parent->name); - $new_token->start = $parent; - if ($carryover) { - $element = clone $parent; - $element->armor['MakeWellFormed_TagClosedError'] = true; - $element->carryover = true; - $this->processToken(array($new_token, $token, $element)); - } else { - $this->insertBefore($new_token); + // 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])) { + $autoclose_ok = true; + break; + } + } + } } - if ($e && !isset($parent->armor['MakeWellFormed_TagClosedError'])) { - if (!$carryover) { - $e->send(E_NOTICE, 'Strategy_MakeWellFormed: Tag auto closed', $parent); + if ($autoclose_ok) { + // errors need to be updated + $new_token = new HTMLPurifier_Token_End($parent->name); + $new_token->start = $parent; + // [TagClosedSuppress] + if ($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', $parent); + } + } + if ($carryover) { + $element = clone $parent; + // [TagClosedAuto] + $element->armor['MakeWellFormed_TagClosedError'] = true; + $element->carryover = true; + $token = $this->processToken(array($new_token, $token, $element)); } else { - $e->send(E_NOTICE, 'Strategy_MakeWellFormed: Tag carryover', $parent); + $token = $this->insertBefore($new_token); } + } else { + $token = $this->remove(); } $reprocess = true; continue; @@ -271,20 +366,26 @@ class HTMLPurifier_Strategy_MakeWellFormed extends HTMLPurifier_Strategy if ($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, $i); + if (isset($token->skip[$i])) { + continue; + } + if ($token->rewind !== null && $token->rewind !== $i) { + continue; + } + $r = $token; + $injector->handleElement($r); + $token = $this->processToken($r, $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'); + throw new HTMLPurifier_Exception( + 'Improper handling of end tag in start code; possible error in MakeWellFormed' + ); } } continue; @@ -298,13 +399,15 @@ class HTMLPurifier_Strategy_MakeWellFormed extends HTMLPurifier_Strategy // 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) - )); + if ($e) { + $e->send(E_WARNING, 'Strategy_MakeWellFormed: Unnecessary end tag to text'); + } + $token = new HTMLPurifier_Token_Text($generator->generateFromToken($token)); } else { - $this->remove(); - if ($e) $e->send(E_WARNING, 'Strategy_MakeWellFormed: Unnecessary end tag removed'); + if ($e) { + $e->send(E_WARNING, 'Strategy_MakeWellFormed: Unnecessary end tag removed'); + } + $token = $this->remove(); } $reprocess = true; continue; @@ -318,10 +421,15 @@ class HTMLPurifier_Strategy_MakeWellFormed extends HTMLPurifier_Strategy if ($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, $i); + if (isset($token->skip[$i])) { + continue; + } + if ($token->rewind !== null && $token->rewind !== $i) { + continue; + } + $r = $token; + $injector->handleEnd($r); + $token = $this->processToken($r, $i); $this->stack[] = $current_parent; $reprocess = true; break; @@ -349,13 +457,15 @@ class HTMLPurifier_Strategy_MakeWellFormed extends HTMLPurifier_Strategy // we didn't find the tag, so remove if ($skipped_tags === false) { if ($escape_invalid_tags) { - $this->swap(new HTMLPurifier_Token_Text( - $generator->generateFromToken($token) - )); - if ($e) $e->send(E_WARNING, 'Strategy_MakeWellFormed: Stray end tag to text'); + if ($e) { + $e->send(E_WARNING, 'Strategy_MakeWellFormed: Stray end tag to text'); + } + $token = new HTMLPurifier_Token_Text($generator->generateFromToken($token)); } else { - $this->remove(); - if ($e) $e->send(E_WARNING, 'Strategy_MakeWellFormed: Stray end tag removed'); + if ($e) { + $e->send(E_WARNING, 'Strategy_MakeWellFormed: Stray end tag removed'); + } + $token = $this->remove(); } $reprocess = true; continue; @@ -366,7 +476,7 @@ class HTMLPurifier_Strategy_MakeWellFormed extends HTMLPurifier_Strategy if ($e) { for ($j = $c - 1; $j > 0; $j--) { // notice we exclude $j == 0, i.e. the current ending tag, from - // the errors... + // the errors... [TagClosedSuppress] if (!isset($skipped_tags[$j]->armor['MakeWellFormed_TagClosedError'])) { $e->send(E_NOTICE, 'Strategy_MakeWellFormed: Tag closed by element end', $skipped_tags[$j]); } @@ -381,24 +491,24 @@ class HTMLPurifier_Strategy_MakeWellFormed extends HTMLPurifier_Strategy $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); + $token = $this->processToken($replace); $reprocess = true; continue; } - $context->destroy('CurrentNesting'); - $context->destroy('InputTokens'); - $context->destroy('InputIndex'); $context->destroy('CurrentToken'); + $context->destroy('CurrentNesting'); + $context->destroy('InputZipper'); - unset($this->injectors, $this->stack, $this->tokens, $this->t); - return $tokens; + unset($this->injectors, $this->stack, $this->tokens); + return $zipper->toArray($token); } /** @@ -417,25 +527,38 @@ class HTMLPurifier_Strategy_MakeWellFormed extends HTMLPurifier_Strategy * 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 + * @param HTMLPurifier_Token|array|int|bool $token Token substitution value + * @param HTMLPurifier_Injector|int $injector Injector that performed the substitution; default is if * this is not an injector related operation. + * @throws HTMLPurifier_Exception */ - protected function processToken($token, $injector = -1) { - + protected function processToken($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 ($token[0] === 0) throw new HTMLPurifier_Exception('Deleting zero tokens is not valid'); + if (is_object($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, $token); + list($old, $r) = $this->zipper->splice($this->token, $delete, $token); if ($injector > -1) { // determine appropriate skips @@ -446,30 +569,32 @@ class HTMLPurifier_Strategy_MakeWellFormed extends HTMLPurifier_Strategy } } - } + return $r; - /** - * Inserts a token before the current token. Cursor now points to this token - */ - private function insertBefore($token) { - array_splice($this->tokens, $this->t, 0, array($token)); } /** - * Removes current token. Cursor now points to new token occupying previously - * occupied space. + * Inserts a token before the current token. Cursor now points to + * this token. You must reprocess after this. + * @param HTMLPurifier_Token $token */ - private function remove() { - array_splice($this->tokens, $this->t, 1); + private function insertBefore($token) + { + // NB not $this->zipper->insertBefore(), due to positioning + // differences + $splice = $this->zipper->splice($this->token, 0, array($token)); + + return $splice[1]; } /** - * Swap current token with new token. Cursor points to new token (no change). + * Removes current token. Cursor now points to new token occupying previously + * occupied space. You must reprocess after this. */ - private function swap($token) { - $this->tokens[$this->t] = $token; + private function remove() + { + return $this->zipper->delete(); } - } // vim: et sw=4 sts=4 |