mirror of
https://github.com/ezyang/htmlpurifier.git
synced 2024-12-23 08:51:53 +00:00
233 lines
8.3 KiB
PHP
233 lines
8.3 KiB
PHP
<?php
|
|
|
|
/**
|
|
* Injects tokens into the document while parsing for well-formedness.
|
|
* This enables "formatter-like" functionality such as auto-paragraphing,
|
|
* smiley-ification and linkification to take place.
|
|
*
|
|
* A note on how handlers create changes; this is done by assigning a new
|
|
* value to the $token reference. These values can take a variety of forms and
|
|
* are best described HTMLPurifier_Strategy_MakeWellFormed->processToken()
|
|
* documentation.
|
|
*
|
|
* @todo Allow injectors to request a re-run on their output. This
|
|
* would help if an operation is recursive.
|
|
*/
|
|
abstract class HTMLPurifier_Injector
|
|
{
|
|
|
|
/**
|
|
* Advisory name of injector, this is for friendly error messages
|
|
*/
|
|
public $name;
|
|
|
|
/**
|
|
* Instance of HTMLPurifier_HTMLDefinition
|
|
*/
|
|
protected $htmlDefinition;
|
|
|
|
/**
|
|
* Reference to CurrentNesting variable in Context. This is an array
|
|
* list of tokens that we are currently "inside"
|
|
*/
|
|
protected $currentNesting;
|
|
|
|
/**
|
|
* Reference to InputTokens variable in Context. This is an array
|
|
* list of the input tokens that are being processed.
|
|
*/
|
|
protected $inputTokens;
|
|
|
|
/**
|
|
* Reference to InputIndex variable in Context. This is an integer
|
|
* array index for $this->inputTokens that indicates what token
|
|
* is currently being processed.
|
|
*/
|
|
protected $inputIndex;
|
|
|
|
/**
|
|
* Array of elements and attributes this injector creates and therefore
|
|
* need to be allowed by the definition. Takes form of
|
|
* array('element' => array('attr', 'attr2'), 'element2')
|
|
*/
|
|
public $needed = array();
|
|
|
|
/**
|
|
* Index of inputTokens to rewind to.
|
|
*/
|
|
protected $rewind = false;
|
|
|
|
/**
|
|
* Rewind to a spot to re-perform processing. This is useful if you
|
|
* deleted a node, and now need to see if this change affected any
|
|
* earlier nodes. Rewinding does not affect other injectors, and can
|
|
* result in infinite loops if not used carefully.
|
|
* @warning HTML Purifier will prevent you from fast-forwarding with this
|
|
* function.
|
|
*/
|
|
public function rewind($index) {
|
|
$this->rewind = $index;
|
|
}
|
|
|
|
/**
|
|
* Retrieves rewind, and then unsets it.
|
|
*/
|
|
public function getRewind() {
|
|
$r = $this->rewind;
|
|
$this->rewind = false;
|
|
return $r;
|
|
}
|
|
|
|
/**
|
|
* Prepares the injector by giving it the config and context objects:
|
|
* this allows references to important variables to be made within
|
|
* the injector. This function also checks if the HTML environment
|
|
* will work with the Injector (see checkNeeded()).
|
|
* @param $config Instance of HTMLPurifier_Config
|
|
* @param $context Instance of HTMLPurifier_Context
|
|
* @return Boolean false if success, string of missing needed element/attribute if failure
|
|
*/
|
|
public function prepare($config, $context) {
|
|
$this->htmlDefinition = $config->getHTMLDefinition();
|
|
// Even though this might fail, some unit tests ignore this and
|
|
// still test checkNeeded, so be careful. Maybe get rid of that
|
|
// dependency.
|
|
$result = $this->checkNeeded($config);
|
|
if ($result !== false) return $result;
|
|
$this->currentNesting =& $context->get('CurrentNesting');
|
|
$this->inputTokens =& $context->get('InputTokens');
|
|
$this->inputIndex =& $context->get('InputIndex');
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* This function checks if the HTML environment
|
|
* will work with the Injector: if p tags are not allowed, the
|
|
* Auto-Paragraphing injector should not be enabled.
|
|
* @param $config Instance of HTMLPurifier_Config
|
|
* @param $context Instance of HTMLPurifier_Context
|
|
* @return Boolean false if success, string of missing needed element/attribute if failure
|
|
*/
|
|
public function checkNeeded($config) {
|
|
$def = $config->getHTMLDefinition();
|
|
foreach ($this->needed as $element => $attributes) {
|
|
if (is_int($element)) $element = $attributes;
|
|
if (!isset($def->info[$element])) return $element;
|
|
if (!is_array($attributes)) continue;
|
|
foreach ($attributes as $name) {
|
|
if (!isset($def->info[$element]->attr[$name])) return "$element.$name";
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* Tests if the context node allows a certain element
|
|
* @param $name Name of element to test for
|
|
* @return True if element is allowed, false if it is not
|
|
*/
|
|
public function allowsElement($name) {
|
|
if (!empty($this->currentNesting)) {
|
|
$parent_token = array_pop($this->currentNesting);
|
|
$this->currentNesting[] = $parent_token;
|
|
$parent = $this->htmlDefinition->info[$parent_token->name];
|
|
} else {
|
|
$parent = $this->htmlDefinition->info_parent_def;
|
|
}
|
|
if (!isset($parent->child->elements[$name]) || isset($parent->excludes[$name])) {
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* Iterator function, which starts with the next token and continues until
|
|
* you reach the end of the input tokens.
|
|
* @warning Please prevent previous references from interfering with this
|
|
* functions by setting $i = null beforehand!
|
|
* @param &$i Current integer index variable for inputTokens
|
|
* @param &$current Current token variable. Do NOT use $token, as that variable is also a reference
|
|
*/
|
|
protected function forward(&$i, &$current) {
|
|
if ($i === null) $i = $this->inputIndex + 1;
|
|
else $i++;
|
|
if (!isset($this->inputTokens[$i])) return false;
|
|
$current = $this->inputTokens[$i];
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* Similar to _forward, but accepts a third parameter $nesting (which
|
|
* should be initialized at 0) and stops when we hit the end tag
|
|
* for the node $this->inputIndex starts in.
|
|
*/
|
|
protected function forwardUntilEndToken(&$i, &$current, &$nesting) {
|
|
$result = $this->forward($i, $current);
|
|
if (!$result) return false;
|
|
if ($nesting === null) $nesting = 0;
|
|
if ($current instanceof HTMLPurifier_Token_Start) $nesting++;
|
|
elseif ($current instanceof HTMLPurifier_Token_End) {
|
|
if ($nesting <= 0) return false;
|
|
$nesting--;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* Iterator function, starts with the previous token and continues until
|
|
* you reach the beginning of input tokens.
|
|
* @warning Please prevent previous references from interfering with this
|
|
* functions by setting $i = null beforehand!
|
|
* @param &$i Current integer index variable for inputTokens
|
|
* @param &$current Current token variable. Do NOT use $token, as that variable is also a reference
|
|
*/
|
|
protected function backward(&$i, &$current) {
|
|
if ($i === null) $i = $this->inputIndex - 1;
|
|
else $i--;
|
|
if ($i < 0) return false;
|
|
$current = $this->inputTokens[$i];
|
|
return true;
|
|
}
|
|
|
|
/**
|
|
* Initializes the iterator at the current position. Use in a do {} while;
|
|
* loop to force the _forward and _backward functions to start at the
|
|
* current location.
|
|
* @warning Please prevent previous references from interfering with this
|
|
* functions by setting $i = null beforehand!
|
|
* @param &$i Current integer index variable for inputTokens
|
|
* @param &$current Current token variable. Do NOT use $token, as that variable is also a reference
|
|
*/
|
|
protected function current(&$i, &$current) {
|
|
if ($i === null) $i = $this->inputIndex;
|
|
$current = $this->inputTokens[$i];
|
|
}
|
|
|
|
/**
|
|
* Handler that is called when a text token is processed
|
|
*/
|
|
public function handleText(&$token) {}
|
|
|
|
/**
|
|
* Handler that is called when a start or empty token is processed
|
|
*/
|
|
public function handleElement(&$token) {}
|
|
|
|
/**
|
|
* Handler that is called when an end token is processed
|
|
*/
|
|
public function handleEnd(&$token) {
|
|
$this->notifyEnd($token);
|
|
}
|
|
|
|
/**
|
|
* Notifier that is called when an end token is processed
|
|
* @note This differs from handlers in that the token is read-only
|
|
* @deprecated
|
|
*/
|
|
public function notifyEnd($token) {}
|
|
|
|
|
|
}
|
|
|