1 files changed, 239 insertions, 0 deletions
diff --git a/lib/htmlpurifier/library/HTMLPurifier/Injector.php b/lib/htmlpurifier/library/HTMLPurifier/Injector.php
new file mode 100644
index 000000000..5922f8130
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+++ b/lib/htmlpurifier/library/HTMLPurifier/Injector.php
@@ -0,0 +1,239 @@
+<?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[$name])) {
+            return false;
+        }
+        // check for exclusion
+        for ($i = count($this->currentNesting) - 2; $i >= 0; $i--) {
+            $node = $this->currentNesting[$i];
+            $def  = $this->htmlDefinition->info[$node->name];
+            if (isset($def->excludes[$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) {}
+
+
+}
+
+// vim: et sw=4 sts=4