mirror of
https://github.com/ezyang/htmlpurifier.git
synced 2024-11-10 07:38:41 +00:00
965be3bd73
The MakeWellFormed strategy uses metadata from HTMLDefinition in order to determine whether or not tokens need to be converted or tags need to be auto-closed. While this functionality is good to have, it is by no means essential, and MakeWellFormed should not error when this information is not available. Signed-off-by: Edward Z. Yang <edwardzyang@thewritingpot.com>
388 lines
16 KiB
PHP
388 lines
16 KiB
PHP
<?php
|
|
|
|
/**
|
|
* Takes tokens makes them well-formed (balance end tags, etc.)
|
|
*/
|
|
class HTMLPurifier_Strategy_MakeWellFormed extends HTMLPurifier_Strategy
|
|
{
|
|
|
|
/**
|
|
* Locally shared variable references
|
|
*/
|
|
protected $inputTokens, $inputIndex, $outputTokens, $currentNesting,
|
|
$currentInjector, $injectors;
|
|
|
|
public function execute($tokens, $config, $context) {
|
|
|
|
$definition = $config->getHTMLDefinition();
|
|
|
|
// local variables
|
|
$generator = new HTMLPurifier_Generator($config, $context);
|
|
$escape_invalid_tags = $config->get('Core', 'EscapeInvalidTags');
|
|
$e = $context->get('ErrorCollector', true);
|
|
|
|
// member variables
|
|
$this->currentNesting = array();
|
|
$this->inputIndex = false;
|
|
$this->inputTokens =& $tokens;
|
|
|
|
// context variables
|
|
$context->register('CurrentNesting', $this->currentNesting);
|
|
$context->register('InputIndex', $this->inputIndex);
|
|
$context->register('InputTokens', $tokens);
|
|
|
|
// -- 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) {
|
|
$injector = "HTMLPurifier_Injector_$injector";
|
|
if (!$b) continue;
|
|
$this->injectors[] = new $injector;
|
|
}
|
|
foreach ($def_injectors as $injector) {
|
|
// assumed to be objects
|
|
$this->injectors[] = $injector;
|
|
}
|
|
foreach ($custom_injectors as $injector) {
|
|
if (is_string($injector)) {
|
|
$injector = "HTMLPurifier_Injector_$injector";
|
|
$injector = new $injector;
|
|
}
|
|
$this->injectors[] = $injector;
|
|
}
|
|
|
|
// array index of the injector that resulted in an array
|
|
// substitution. This enables processTokens() to know which
|
|
// injectors are affected by the added tokens and which are
|
|
// not (namely, the ones after the current injector are not
|
|
// affected)
|
|
$this->currentInjector = false;
|
|
|
|
// give the injectors references to the definition and context
|
|
// variables for performance reasons
|
|
foreach ($this->injectors as $i => $injector) {
|
|
$error = $injector->prepare($config, $context);
|
|
if (!$error) continue;
|
|
array_splice($this->injectors, $i, 1); // rm the injector
|
|
trigger_error("Cannot enable {$injector->name} injector because $error is not allowed", E_USER_WARNING);
|
|
}
|
|
|
|
// warning: most foreach loops follow the convention $i => $injector.
|
|
// Don't define these as loop-wide variables, please!
|
|
|
|
// -- end INJECTOR --
|
|
|
|
$token = false;
|
|
$context->register('CurrentToken', $token);
|
|
|
|
// isset is in loop because $tokens size changes during loop exec
|
|
for ($this->inputIndex = 0; isset($tokens[$this->inputIndex]); $this->inputIndex++) {
|
|
|
|
// if all goes well, this token will be passed through unharmed
|
|
$token = $tokens[$this->inputIndex];
|
|
|
|
//echo '<hr>';
|
|
//printTokens($tokens, $this->inputIndex);
|
|
//var_dump($this->currentNesting);
|
|
|
|
foreach ($this->injectors as $injector) {
|
|
if ($injector->skip > 0) $injector->skip--;
|
|
}
|
|
|
|
// quick-check: if it's not a tag, no need to process
|
|
if (empty( $token->is_tag )) {
|
|
if ($token instanceof HTMLPurifier_Token_Text) {
|
|
// injector handler code; duplicated for performance reasons
|
|
foreach ($this->injectors as $i => $injector) {
|
|
if (!$injector->skip) $injector->handleText($token);
|
|
if (is_array($token) || is_int($token)) {
|
|
$this->currentInjector = $i;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
$this->processToken($token, $config, $context);
|
|
continue;
|
|
}
|
|
|
|
if (isset($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) {
|
|
// test if it claims to be a start tag but is empty
|
|
$token = new HTMLPurifier_Token_Empty($token->name, $token->attr);
|
|
$ok = true;
|
|
} elseif ($type && $type !== 'empty' && $token instanceof HTMLPurifier_Token_Empty) {
|
|
// claims to be empty but really is a start tag
|
|
$token = array(
|
|
new HTMLPurifier_Token_Start($token->name, $token->attr),
|
|
new HTMLPurifier_Token_End($token->name)
|
|
);
|
|
$ok = true;
|
|
} elseif ($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->currentNesting)) {
|
|
|
|
$parent = array_pop($this->currentNesting);
|
|
if (isset($definition->info[$parent->name])) {
|
|
$elements = $definition->info[$parent->name]->child->elements;
|
|
$autoclose = !isset($elements[$token->name]);
|
|
} else {
|
|
$autoclose = false;
|
|
}
|
|
|
|
if ($autoclose) {
|
|
if ($e) $e->send(E_NOTICE, 'Strategy_MakeWellFormed: Tag auto closed', $parent);
|
|
// insert parent end tag before this tag;
|
|
// end tag isn't processed, but this tag is processed again
|
|
$new_token = new HTMLPurifier_Token_End($parent->name);
|
|
$new_token->start = $parent;
|
|
$this->insertBefore($new_token);
|
|
continue;
|
|
}
|
|
|
|
$this->currentNesting[] = $parent; // undo the pop
|
|
}
|
|
$ok = true;
|
|
}
|
|
|
|
// injector handler code; duplicated for performance reasons
|
|
if ($ok) {
|
|
foreach ($this->injectors as $i => $injector) {
|
|
if (!$injector->skip) $injector->handleElement($token);
|
|
if (is_array($token) || is_int($token)) {
|
|
$this->currentInjector = $i;
|
|
break;
|
|
}
|
|
}
|
|
$this->processToken($token, $config, $context);
|
|
continue;
|
|
}
|
|
|
|
// sanity check: we should be dealing with a closing tag
|
|
if (!$token instanceof HTMLPurifier_Token_End) {
|
|
$this->remove();
|
|
continue;
|
|
}
|
|
|
|
// make sure that we have something open
|
|
if (empty($this->currentNesting)) {
|
|
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');
|
|
}
|
|
continue;
|
|
}
|
|
|
|
// first, check for the simplest case: everything closes neatly
|
|
$current_parent = array_pop($this->currentNesting);
|
|
if ($current_parent->name == $token->name) {
|
|
$token->start = $current_parent;
|
|
foreach ($this->injectors as $i => $injector) {
|
|
$injector->notifyEnd($token);
|
|
}
|
|
continue;
|
|
}
|
|
|
|
// okay, so we're trying to close the wrong tag
|
|
|
|
// undo the pop previous pop
|
|
$this->currentNesting[] = $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->currentNesting);
|
|
// -2 because -1 is the last element, but we already checked that
|
|
$skipped_tags = false;
|
|
for ($i = $size - 2; $i >= 0; $i--) {
|
|
if ($this->currentNesting[$i]->name == $token->name) {
|
|
// current nesting is modified
|
|
$skipped_tags = array_splice($this->currentNesting, $i);
|
|
break;
|
|
}
|
|
}
|
|
|
|
// we still didn't find the tag, so remove
|
|
if ($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');
|
|
}
|
|
continue;
|
|
}
|
|
|
|
// okay, we found it, close all the skipped tags
|
|
// note that skipped tags contains the element we need closed
|
|
$this->remove();
|
|
for ($i = count($skipped_tags) - 1; $i >= 0; $i--) {
|
|
// please don't redefine $i!
|
|
if ($i && $e && !isset($skipped_tags[$i]->armor['MakeWellFormed_TagClosedError'])) {
|
|
$e->send(E_NOTICE, 'Strategy_MakeWellFormed: Tag closed by element end', $skipped_tags[$i]);
|
|
}
|
|
$new_token = new HTMLPurifier_Token_End($skipped_tags[$i]->name);
|
|
$new_token->start = $skipped_tags[$i];
|
|
$this->insertAfter($new_token);
|
|
//printTokens($tokens, $this->inputIndex);
|
|
//var_dump($this->currentNesting);
|
|
foreach ($this->injectors as $injector) {
|
|
$injector->notifyEnd($new_token);
|
|
}
|
|
}
|
|
}
|
|
|
|
$context->destroy('CurrentNesting');
|
|
$context->destroy('InputTokens');
|
|
$context->destroy('InputIndex');
|
|
$context->destroy('CurrentToken');
|
|
|
|
// we're at the end now, fix all still unclosed tags (this is
|
|
// duplicated from the end of the loop with some slight modifications)
|
|
// not using $skipped_tags since it would invariably be all of them
|
|
if (!empty($this->currentNesting)) {
|
|
for ($i = count($this->currentNesting) - 1; $i >= 0; $i--) {
|
|
// please don't redefine $i!
|
|
if ($e && !isset($this->currentNesting[$i]->armor['MakeWellFormed_TagClosedError'])) {
|
|
$e->send(E_NOTICE, 'Strategy_MakeWellFormed: Tag closed by document end', $this->currentNesting[$i]);
|
|
}
|
|
// instead of splice, since we know this is the end
|
|
$tokens[] = $new_token = new HTMLPurifier_Token_End($this->currentNesting[$i]->name);
|
|
$new_token->start = $this->currentNesting[$i];
|
|
foreach ($this->injectors as $injector) {
|
|
$injector->notifyEnd($new_token);
|
|
}
|
|
}
|
|
}
|
|
|
|
unset($this->outputTokens, $this->injectors, $this->currentInjector,
|
|
$this->currentNesting, $this->inputTokens, $this->inputIndex);
|
|
return $tokens;
|
|
}
|
|
|
|
/**
|
|
* Inserts a token before the current token. Cursor now points to this token.
|
|
*/
|
|
protected function insertBefore($token) {
|
|
array_splice($this->inputTokens, $this->inputIndex, 0, array($token));
|
|
}
|
|
|
|
/**
|
|
* Inserts a token after the current token. Cursor now points to this token.
|
|
*/
|
|
protected function insertAfter($token) {
|
|
array_splice($this->inputTokens, ++$this->inputIndex, 0, array($token));
|
|
}
|
|
|
|
/**
|
|
* Removes current token. Cursor now points to previous token.
|
|
*/
|
|
protected function remove() {
|
|
array_splice($this->inputTokens, $this->inputIndex--, 1);
|
|
}
|
|
|
|
/**
|
|
* Swap current token with new token. Cursor points to new token (no change).
|
|
*/
|
|
protected function swap($token) {
|
|
array_splice($this->inputTokens, $this->inputIndex, 1, array($token));
|
|
}
|
|
|
|
/**
|
|
* 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 $token is a regular token, it is swapped with the current token,
|
|
* and the stack is updated.
|
|
*
|
|
* If $token is false, the current token is deleted.
|
|
*/
|
|
protected function processToken($token, $config, $context) {
|
|
if (is_array($token) || is_int($token)) {
|
|
// the original token was overloaded by an injector, time
|
|
// to some fancy acrobatics
|
|
if (is_array($token)) {
|
|
array_splice($this->inputTokens, $this->inputIndex, 1, $token);
|
|
} else {
|
|
array_splice($this->inputTokens, $this->inputIndex, $token, array());
|
|
}
|
|
if ($this->injectors) {
|
|
$rewind = $this->injectors[$this->currentInjector]->getRewind();
|
|
if ($rewind < 0) $rewind = 0;
|
|
if ($rewind !== false) {
|
|
$offset = $this->inputIndex - $rewind;
|
|
if ($this->injectors) {
|
|
foreach ($this->injectors as $i => $injector) {
|
|
if ($i == $this->currentInjector) {
|
|
$injector->skip = 0;
|
|
} else {
|
|
$injector->skip += $offset;
|
|
}
|
|
}
|
|
}
|
|
for ($this->inputIndex--; $this->inputIndex >= $rewind; $this->inputIndex--) {
|
|
$prev = $this->inputTokens[$this->inputIndex];
|
|
if ($prev instanceof HTMLPurifier_Token_Start) array_pop($this->currentNesting);
|
|
elseif ($prev instanceof HTMLPurifier_Token_End) $this->currentNesting[] = $prev->start;
|
|
}
|
|
$this->inputIndex++;
|
|
} else {
|
|
// adjust the injector skips based on the array substitution
|
|
$offset = is_array($token) ? count($token) : 0;
|
|
for ($i = 0; $i <= $this->currentInjector; $i++) {
|
|
// because of the skip back, we need to add one more
|
|
// for uninitialized injectors. I'm not exactly
|
|
// sure why this is the case, but I think it has to
|
|
// do with the fact that we're decrementing skips
|
|
// before re-checking text
|
|
if (!$this->injectors[$i]->skip) $this->injectors[$i]->skip++;
|
|
$this->injectors[$i]->skip += $offset;
|
|
}
|
|
}
|
|
}
|
|
// ensure that we reprocess these tokens with the other injectors
|
|
--$this->inputIndex;
|
|
|
|
} elseif ($token) {
|
|
// regular case
|
|
$this->swap($token);
|
|
if ($token instanceof HTMLPurifier_Token_Start) {
|
|
$this->currentNesting[] = $token;
|
|
} elseif ($token instanceof HTMLPurifier_Token_End) {
|
|
// not actually used
|
|
$token->start = array_pop($this->currentNesting);
|
|
}
|
|
} else {
|
|
$this->remove();
|
|
}
|
|
}
|
|
|
|
}
|
|
|