286 lines
		
	
	
		
			9.7 KiB
		
	
	
	
		
			PHP
		
	
	
		
		
			
		
	
	
			286 lines
		
	
	
		
			9.7 KiB
		
	
	
	
		
			PHP
		
	
	
|  | <?php | ||
|  | 
 | ||
|  | // if want to implement error collecting here, we'll need to use some sort
 | ||
|  | // of global data (probably trigger_error) because it's impossible to pass
 | ||
|  | // $config or $context to the callback functions.
 | ||
|  | 
 | ||
|  | /** | ||
|  |  * Handles referencing and derefencing character entities | ||
|  |  */ | ||
|  | class HTMLPurifier_EntityParser | ||
|  | { | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Reference to entity lookup table. | ||
|  |      * @type HTMLPurifier_EntityLookup | ||
|  |      */ | ||
|  |     protected $_entity_lookup; | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Callback regex string for entities in text. | ||
|  |      * @type string | ||
|  |      */ | ||
|  |     protected $_textEntitiesRegex; | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Callback regex string for entities in attributes. | ||
|  |      * @type string | ||
|  |      */ | ||
|  |     protected $_attrEntitiesRegex; | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Tests if the beginning of a string is a semi-optional regex | ||
|  |      */ | ||
|  |     protected $_semiOptionalPrefixRegex; | ||
|  | 
 | ||
|  |     public function __construct() { | ||
|  |         // From
 | ||
|  |         // http://stackoverflow.com/questions/15532252/why-is-reg-being-rendered-as-without-the-bounding-semicolon
 | ||
|  |         $semi_optional = "quot|QUOT|lt|LT|gt|GT|amp|AMP|AElig|Aacute|Acirc|Agrave|Aring|Atilde|Auml|COPY|Ccedil|ETH|Eacute|Ecirc|Egrave|Euml|Iacute|Icirc|Igrave|Iuml|Ntilde|Oacute|Ocirc|Ograve|Oslash|Otilde|Ouml|REG|THORN|Uacute|Ucirc|Ugrave|Uuml|Yacute|aacute|acirc|acute|aelig|agrave|aring|atilde|auml|brvbar|ccedil|cedil|cent|copy|curren|deg|divide|eacute|ecirc|egrave|eth|euml|frac12|frac14|frac34|iacute|icirc|iexcl|igrave|iquest|iuml|laquo|macr|micro|middot|nbsp|not|ntilde|oacute|ocirc|ograve|ordf|ordm|oslash|otilde|ouml|para|plusmn|pound|raquo|reg|sect|shy|sup1|sup2|sup3|szlig|thorn|times|uacute|ucirc|ugrave|uml|uuml|yacute|yen|yuml"; | ||
|  | 
 | ||
|  |         // NB: three empty captures to put the fourth match in the right
 | ||
|  |         // place
 | ||
|  |         $this->_semiOptionalPrefixRegex = "/&()()()($semi_optional)/"; | ||
|  | 
 | ||
|  |         $this->_textEntitiesRegex = | ||
|  |             '/&(?:'. | ||
|  |             // hex
 | ||
|  |             '[#]x([a-fA-F0-9]+);?|'. | ||
|  |             // dec
 | ||
|  |             '[#]0*(\d+);?|'. | ||
|  |             // string (mandatory semicolon)
 | ||
|  |             // NB: order matters: match semicolon preferentially
 | ||
|  |             '([A-Za-z_:][A-Za-z0-9.\-_:]*);|'. | ||
|  |             // string (optional semicolon)
 | ||
|  |             "($semi_optional)". | ||
|  |             ')/'; | ||
|  | 
 | ||
|  |         $this->_attrEntitiesRegex = | ||
|  |             '/&(?:'. | ||
|  |             // hex
 | ||
|  |             '[#]x([a-fA-F0-9]+);?|'. | ||
|  |             // dec
 | ||
|  |             '[#]0*(\d+);?|'. | ||
|  |             // string (mandatory semicolon)
 | ||
|  |             // NB: order matters: match semicolon preferentially
 | ||
|  |             '([A-Za-z_:][A-Za-z0-9.\-_:]*);|'. | ||
|  |             // string (optional semicolon)
 | ||
|  |             // don't match if trailing is equals or alphanumeric (URL
 | ||
|  |             // like)
 | ||
|  |             "($semi_optional)(?![=;A-Za-z0-9])". | ||
|  |             ')/'; | ||
|  | 
 | ||
|  |     } | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Substitute entities with the parsed equivalents.  Use this on | ||
|  |      * textual data in an HTML document (as opposed to attributes.) | ||
|  |      * | ||
|  |      * @param string $string String to have entities parsed. | ||
|  |      * @return string Parsed string. | ||
|  |      */ | ||
|  |     public function substituteTextEntities($string) | ||
|  |     { | ||
|  |         return preg_replace_callback( | ||
|  |             $this->_textEntitiesRegex, | ||
|  |             array($this, 'entityCallback'), | ||
|  |             $string | ||
|  |         ); | ||
|  |     } | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Substitute entities with the parsed equivalents.  Use this on | ||
|  |      * attribute contents in documents. | ||
|  |      * | ||
|  |      * @param string $string String to have entities parsed. | ||
|  |      * @return string Parsed string. | ||
|  |      */ | ||
|  |     public function substituteAttrEntities($string) | ||
|  |     { | ||
|  |         return preg_replace_callback( | ||
|  |             $this->_attrEntitiesRegex, | ||
|  |             array($this, 'entityCallback'), | ||
|  |             $string | ||
|  |         ); | ||
|  |     } | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Callback function for substituteNonSpecialEntities() that does the work. | ||
|  |      * | ||
|  |      * @param array $matches  PCRE matches array, with 0 the entire match, and | ||
|  |      *                  either index 1, 2 or 3 set with a hex value, dec value, | ||
|  |      *                  or string (respectively). | ||
|  |      * @return string Replacement string. | ||
|  |      */ | ||
|  | 
 | ||
|  |     protected function entityCallback($matches) | ||
|  |     { | ||
|  |         $entity = $matches[0]; | ||
|  |         $hex_part = @$matches[1]; | ||
|  |         $dec_part = @$matches[2]; | ||
|  |         $named_part = empty($matches[3]) ? (empty($matches[4]) ? "" : $matches[4]) : $matches[3]; | ||
|  |         if ($hex_part !== NULL && $hex_part !== "") { | ||
|  |             return HTMLPurifier_Encoder::unichr(hexdec($hex_part)); | ||
|  |         } elseif ($dec_part !== NULL && $dec_part !== "") { | ||
|  |             return HTMLPurifier_Encoder::unichr((int) $dec_part); | ||
|  |         } else { | ||
|  |             if (!$this->_entity_lookup) { | ||
|  |                 $this->_entity_lookup = HTMLPurifier_EntityLookup::instance(); | ||
|  |             } | ||
|  |             if (isset($this->_entity_lookup->table[$named_part])) { | ||
|  |                 return $this->_entity_lookup->table[$named_part]; | ||
|  |             } else { | ||
|  |                 // exact match didn't match anything, so test if
 | ||
|  |                 // any of the semicolon optional match the prefix.
 | ||
|  |                 // Test that this is an EXACT match is important to
 | ||
|  |                 // prevent infinite loop
 | ||
|  |                 if (!empty($matches[3])) { | ||
|  |                     return preg_replace_callback( | ||
|  |                         $this->_semiOptionalPrefixRegex, | ||
|  |                         array($this, 'entityCallback'), | ||
|  |                         $entity | ||
|  |                     ); | ||
|  |                 } | ||
|  |                 return $entity; | ||
|  |             } | ||
|  |         } | ||
|  |     } | ||
|  | 
 | ||
|  |     // LEGACY CODE BELOW
 | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Callback regex string for parsing entities. | ||
|  |      * @type string | ||
|  |      */ | ||
|  |     protected $_substituteEntitiesRegex = | ||
|  |         '/&(?:[#]x([a-fA-F0-9]+)|[#]0*(\d+)|([A-Za-z_:][A-Za-z0-9.\-_:]*));?/'; | ||
|  |         //     1. hex             2. dec      3. string (XML style)
 | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Decimal to parsed string conversion table for special entities. | ||
|  |      * @type array | ||
|  |      */ | ||
|  |     protected $_special_dec2str = | ||
|  |             array( | ||
|  |                     34 => '"', | ||
|  |                     38 => '&', | ||
|  |                     39 => "'", | ||
|  |                     60 => '<', | ||
|  |                     62 => '>' | ||
|  |             ); | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Stripped entity names to decimal conversion table for special entities. | ||
|  |      * @type array | ||
|  |      */ | ||
|  |     protected $_special_ent2dec = | ||
|  |             array( | ||
|  |                     'quot' => 34, | ||
|  |                     'amp'  => 38, | ||
|  |                     'lt'   => 60, | ||
|  |                     'gt'   => 62 | ||
|  |             ); | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Substitutes non-special entities with their parsed equivalents. Since | ||
|  |      * running this whenever you have parsed character is t3h 5uck, we run | ||
|  |      * it before everything else. | ||
|  |      * | ||
|  |      * @param string $string String to have non-special entities parsed. | ||
|  |      * @return string Parsed string. | ||
|  |      */ | ||
|  |     public function substituteNonSpecialEntities($string) | ||
|  |     { | ||
|  |         // it will try to detect missing semicolons, but don't rely on it
 | ||
|  |         return preg_replace_callback( | ||
|  |             $this->_substituteEntitiesRegex, | ||
|  |             array($this, 'nonSpecialEntityCallback'), | ||
|  |             $string | ||
|  |         ); | ||
|  |     } | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Callback function for substituteNonSpecialEntities() that does the work. | ||
|  |      * | ||
|  |      * @param array $matches  PCRE matches array, with 0 the entire match, and | ||
|  |      *                  either index 1, 2 or 3 set with a hex value, dec value, | ||
|  |      *                  or string (respectively). | ||
|  |      * @return string Replacement string. | ||
|  |      */ | ||
|  | 
 | ||
|  |     protected function nonSpecialEntityCallback($matches) | ||
|  |     { | ||
|  |         // replaces all but big five
 | ||
|  |         $entity = $matches[0]; | ||
|  |         $is_num = (@$matches[0][1] === '#'); | ||
|  |         if ($is_num) { | ||
|  |             $is_hex = (@$entity[2] === 'x'); | ||
|  |             $code = $is_hex ? hexdec($matches[1]) : (int) $matches[2]; | ||
|  |             // abort for special characters
 | ||
|  |             if (isset($this->_special_dec2str[$code])) { | ||
|  |                 return $entity; | ||
|  |             } | ||
|  |             return HTMLPurifier_Encoder::unichr($code); | ||
|  |         } else { | ||
|  |             if (isset($this->_special_ent2dec[$matches[3]])) { | ||
|  |                 return $entity; | ||
|  |             } | ||
|  |             if (!$this->_entity_lookup) { | ||
|  |                 $this->_entity_lookup = HTMLPurifier_EntityLookup::instance(); | ||
|  |             } | ||
|  |             if (isset($this->_entity_lookup->table[$matches[3]])) { | ||
|  |                 return $this->_entity_lookup->table[$matches[3]]; | ||
|  |             } else { | ||
|  |                 return $entity; | ||
|  |             } | ||
|  |         } | ||
|  |     } | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Substitutes only special entities with their parsed equivalents. | ||
|  |      * | ||
|  |      * @notice We try to avoid calling this function because otherwise, it | ||
|  |      * would have to be called a lot (for every parsed section). | ||
|  |      * | ||
|  |      * @param string $string String to have non-special entities parsed. | ||
|  |      * @return string Parsed string. | ||
|  |      */ | ||
|  |     public function substituteSpecialEntities($string) | ||
|  |     { | ||
|  |         return preg_replace_callback( | ||
|  |             $this->_substituteEntitiesRegex, | ||
|  |             array($this, 'specialEntityCallback'), | ||
|  |             $string | ||
|  |         ); | ||
|  |     } | ||
|  | 
 | ||
|  |     /** | ||
|  |      * Callback function for substituteSpecialEntities() that does the work. | ||
|  |      * | ||
|  |      * This callback has same syntax as nonSpecialEntityCallback(). | ||
|  |      * | ||
|  |      * @param array $matches  PCRE-style matches array, with 0 the entire match, and | ||
|  |      *                  either index 1, 2 or 3 set with a hex value, dec value, | ||
|  |      *                  or string (respectively). | ||
|  |      * @return string Replacement string. | ||
|  |      */ | ||
|  |     protected function specialEntityCallback($matches) | ||
|  |     { | ||
|  |         $entity = $matches[0]; | ||
|  |         $is_num = (@$matches[0][1] === '#'); | ||
|  |         if ($is_num) { | ||
|  |             $is_hex = (@$entity[2] === 'x'); | ||
|  |             $int = $is_hex ? hexdec($matches[1]) : (int) $matches[2]; | ||
|  |             return isset($this->_special_dec2str[$int]) ? | ||
|  |                 $this->_special_dec2str[$int] : | ||
|  |                 $entity; | ||
|  |         } else { | ||
|  |             return isset($this->_special_ent2dec[$matches[3]]) ? | ||
|  |                 $this->_special_dec2str[$this->_special_ent2dec[$matches[3]]] : | ||
|  |                 $entity; | ||
|  |         } | ||
|  |     } | ||
|  | } | ||
|  | 
 | ||
|  | // vim: et sw=4 sts=4
 |