- Move Friendica namespace to `src` - Move required `ezyang/htmlpurifier` to vendor - Remove existing static autoloader - Change boot.php reference to the autoloader
		
			
				
	
	
		
			611 lines
		
	
	
	
		
			25 KiB
		
	
	
	
		
			PHP
		
	
	
	
	
	
			
		
		
	
	
			611 lines
		
	
	
	
		
			25 KiB
		
	
	
	
		
			PHP
		
	
	
	
	
	
| <?php
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| 
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| /**
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|  * A UTF-8 specific character encoder that handles cleaning and transforming.
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|  * @note All functions in this class should be static.
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|  */
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| class HTMLPurifier_Encoder
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| {
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| 
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|     /**
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|      * Constructor throws fatal error if you attempt to instantiate class
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|      */
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|     private function __construct()
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|     {
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|         trigger_error('Cannot instantiate encoder, call methods statically', E_USER_ERROR);
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|     }
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| 
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|     /**
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|      * Error-handler that mutes errors, alternative to shut-up operator.
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|      */
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|     public static function muteErrorHandler()
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|     {
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|     }
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| 
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|     /**
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|      * iconv wrapper which mutes errors, but doesn't work around bugs.
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|      * @param string $in Input encoding
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|      * @param string $out Output encoding
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|      * @param string $text The text to convert
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|      * @return string
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|      */
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|     public static function unsafeIconv($in, $out, $text)
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|     {
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|         set_error_handler(array('HTMLPurifier_Encoder', 'muteErrorHandler'));
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|         $r = iconv($in, $out, $text);
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|         restore_error_handler();
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|         return $r;
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|     }
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| 
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|     /**
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|      * iconv wrapper which mutes errors and works around bugs.
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|      * @param string $in Input encoding
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|      * @param string $out Output encoding
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|      * @param string $text The text to convert
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|      * @param int $max_chunk_size
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|      * @return string
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|      */
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|     public static function iconv($in, $out, $text, $max_chunk_size = 8000)
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|     {
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|         $code = self::testIconvTruncateBug();
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|         if ($code == self::ICONV_OK) {
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|             return self::unsafeIconv($in, $out, $text);
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|         } elseif ($code == self::ICONV_TRUNCATES) {
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|             // we can only work around this if the input character set
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|             // is utf-8
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|             if ($in == 'utf-8') {
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|                 if ($max_chunk_size < 4) {
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|                     trigger_error('max_chunk_size is too small', E_USER_WARNING);
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|                     return false;
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|                 }
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|                 // split into 8000 byte chunks, but be careful to handle
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|                 // multibyte boundaries properly
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|                 if (($c = strlen($text)) <= $max_chunk_size) {
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|                     return self::unsafeIconv($in, $out, $text);
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|                 }
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|                 $r = '';
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|                 $i = 0;
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|                 while (true) {
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|                     if ($i + $max_chunk_size >= $c) {
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|                         $r .= self::unsafeIconv($in, $out, substr($text, $i));
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|                         break;
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|                     }
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|                     // wibble the boundary
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|                     if (0x80 != (0xC0 & ord($text[$i + $max_chunk_size]))) {
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|                         $chunk_size = $max_chunk_size;
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|                     } elseif (0x80 != (0xC0 & ord($text[$i + $max_chunk_size - 1]))) {
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|                         $chunk_size = $max_chunk_size - 1;
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|                     } elseif (0x80 != (0xC0 & ord($text[$i + $max_chunk_size - 2]))) {
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|                         $chunk_size = $max_chunk_size - 2;
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|                     } elseif (0x80 != (0xC0 & ord($text[$i + $max_chunk_size - 3]))) {
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|                         $chunk_size = $max_chunk_size - 3;
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|                     } else {
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|                         return false; // rather confusing UTF-8...
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|                     }
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|                     $chunk = substr($text, $i, $chunk_size); // substr doesn't mind overlong lengths
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|                     $r .= self::unsafeIconv($in, $out, $chunk);
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|                     $i += $chunk_size;
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|                 }
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|                 return $r;
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|             } else {
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|                 return false;
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|             }
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|         } else {
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|             return false;
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|         }
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|     }
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| 
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|     /**
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|      * Cleans a UTF-8 string for well-formedness and SGML validity
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|      *
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|      * It will parse according to UTF-8 and return a valid UTF8 string, with
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|      * non-SGML codepoints excluded.
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|      *
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|      * @param string $str The string to clean
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|      * @param bool $force_php
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|      * @return string
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|      *
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|      * @note Just for reference, the non-SGML code points are 0 to 31 and
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|      *       127 to 159, inclusive.  However, we allow code points 9, 10
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|      *       and 13, which are the tab, line feed and carriage return
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|      *       respectively. 128 and above the code points map to multibyte
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|      *       UTF-8 representations.
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|      *
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|      * @note Fallback code adapted from utf8ToUnicode by Henri Sivonen and
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|      *       hsivonen@iki.fi at <http://iki.fi/hsivonen/php-utf8/> under the
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|      *       LGPL license.  Notes on what changed are inside, but in general,
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|      *       the original code transformed UTF-8 text into an array of integer
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|      *       Unicode codepoints. Understandably, transforming that back to
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|      *       a string would be somewhat expensive, so the function was modded to
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|      *       directly operate on the string.  However, this discourages code
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|      *       reuse, and the logic enumerated here would be useful for any
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|      *       function that needs to be able to understand UTF-8 characters.
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|      *       As of right now, only smart lossless character encoding converters
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|      *       would need that, and I'm probably not going to implement them.
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|      *       Once again, PHP 6 should solve all our problems.
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|      */
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|     public static function cleanUTF8($str, $force_php = false)
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|     {
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|         // UTF-8 validity is checked since PHP 4.3.5
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|         // This is an optimization: if the string is already valid UTF-8, no
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|         // need to do PHP stuff. 99% of the time, this will be the case.
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|         // The regexp matches the XML char production, as well as well as excluding
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|         // non-SGML codepoints U+007F to U+009F
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|         if (preg_match(
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|             '/^[\x{9}\x{A}\x{D}\x{20}-\x{7E}\x{A0}-\x{D7FF}\x{E000}-\x{FFFD}\x{10000}-\x{10FFFF}]*$/Du',
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|             $str
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|         )) {
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|             return $str;
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|         }
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| 
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|         $mState = 0; // cached expected number of octets after the current octet
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|                      // until the beginning of the next UTF8 character sequence
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|         $mUcs4  = 0; // cached Unicode character
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|         $mBytes = 1; // cached expected number of octets in the current sequence
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| 
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|         // original code involved an $out that was an array of Unicode
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|         // codepoints.  Instead of having to convert back into UTF-8, we've
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|         // decided to directly append valid UTF-8 characters onto a string
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|         // $out once they're done.  $char accumulates raw bytes, while $mUcs4
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|         // turns into the Unicode code point, so there's some redundancy.
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| 
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|         $out = '';
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|         $char = '';
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| 
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|         $len = strlen($str);
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|         for ($i = 0; $i < $len; $i++) {
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|             $in = ord($str{$i});
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|             $char .= $str[$i]; // append byte to char
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|             if (0 == $mState) {
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|                 // When mState is zero we expect either a US-ASCII character
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|                 // or a multi-octet sequence.
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|                 if (0 == (0x80 & ($in))) {
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|                     // US-ASCII, pass straight through.
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|                     if (($in <= 31 || $in == 127) &&
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|                         !($in == 9 || $in == 13 || $in == 10) // save \r\t\n
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|                     ) {
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|                         // control characters, remove
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|                     } else {
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|                         $out .= $char;
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|                     }
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|                     // reset
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|                     $char = '';
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|                     $mBytes = 1;
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|                 } elseif (0xC0 == (0xE0 & ($in))) {
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|                     // First octet of 2 octet sequence
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|                     $mUcs4 = ($in);
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|                     $mUcs4 = ($mUcs4 & 0x1F) << 6;
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|                     $mState = 1;
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|                     $mBytes = 2;
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|                 } elseif (0xE0 == (0xF0 & ($in))) {
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|                     // First octet of 3 octet sequence
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|                     $mUcs4 = ($in);
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|                     $mUcs4 = ($mUcs4 & 0x0F) << 12;
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|                     $mState = 2;
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|                     $mBytes = 3;
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|                 } elseif (0xF0 == (0xF8 & ($in))) {
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|                     // First octet of 4 octet sequence
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|                     $mUcs4 = ($in);
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|                     $mUcs4 = ($mUcs4 & 0x07) << 18;
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|                     $mState = 3;
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|                     $mBytes = 4;
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|                 } elseif (0xF8 == (0xFC & ($in))) {
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|                     // First octet of 5 octet sequence.
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|                     //
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|                     // This is illegal because the encoded codepoint must be
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|                     // either:
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|                     // (a) not the shortest form or
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|                     // (b) outside the Unicode range of 0-0x10FFFF.
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|                     // Rather than trying to resynchronize, we will carry on
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|                     // until the end of the sequence and let the later error
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|                     // handling code catch it.
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|                     $mUcs4 = ($in);
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|                     $mUcs4 = ($mUcs4 & 0x03) << 24;
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|                     $mState = 4;
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|                     $mBytes = 5;
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|                 } elseif (0xFC == (0xFE & ($in))) {
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|                     // First octet of 6 octet sequence, see comments for 5
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|                     // octet sequence.
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|                     $mUcs4 = ($in);
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|                     $mUcs4 = ($mUcs4 & 1) << 30;
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|                     $mState = 5;
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|                     $mBytes = 6;
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|                 } else {
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|                     // Current octet is neither in the US-ASCII range nor a
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|                     // legal first octet of a multi-octet sequence.
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|                     $mState = 0;
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|                     $mUcs4  = 0;
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|                     $mBytes = 1;
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|                     $char = '';
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|                 }
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|             } else {
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|                 // When mState is non-zero, we expect a continuation of the
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|                 // multi-octet sequence
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|                 if (0x80 == (0xC0 & ($in))) {
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|                     // Legal continuation.
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|                     $shift = ($mState - 1) * 6;
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|                     $tmp = $in;
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|                     $tmp = ($tmp & 0x0000003F) << $shift;
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|                     $mUcs4 |= $tmp;
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| 
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|                     if (0 == --$mState) {
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|                         // End of the multi-octet sequence. mUcs4 now contains
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|                         // the final Unicode codepoint to be output
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| 
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|                         // Check for illegal sequences and codepoints.
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| 
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|                         // From Unicode 3.1, non-shortest form is illegal
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|                         if (((2 == $mBytes) && ($mUcs4 < 0x0080)) ||
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|                             ((3 == $mBytes) && ($mUcs4 < 0x0800)) ||
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|                             ((4 == $mBytes) && ($mUcs4 < 0x10000)) ||
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|                             (4 < $mBytes) ||
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|                             // From Unicode 3.2, surrogate characters = illegal
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|                             (($mUcs4 & 0xFFFFF800) == 0xD800) ||
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|                             // Codepoints outside the Unicode range are illegal
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|                             ($mUcs4 > 0x10FFFF)
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|                         ) {
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| 
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|                         } elseif (0xFEFF != $mUcs4 && // omit BOM
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|                             // check for valid Char unicode codepoints
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|                             (
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|                                 0x9 == $mUcs4 ||
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|                                 0xA == $mUcs4 ||
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|                                 0xD == $mUcs4 ||
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|                                 (0x20 <= $mUcs4 && 0x7E >= $mUcs4) ||
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|                                 // 7F-9F is not strictly prohibited by XML,
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|                                 // but it is non-SGML, and thus we don't allow it
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|                                 (0xA0 <= $mUcs4 && 0xD7FF >= $mUcs4) ||
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|                                 (0x10000 <= $mUcs4 && 0x10FFFF >= $mUcs4)
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|                             )
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|                         ) {
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|                             $out .= $char;
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|                         }
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|                         // initialize UTF8 cache (reset)
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|                         $mState = 0;
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|                         $mUcs4  = 0;
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|                         $mBytes = 1;
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|                         $char = '';
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|                     }
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|                 } else {
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|                     // ((0xC0 & (*in) != 0x80) && (mState != 0))
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|                     // Incomplete multi-octet sequence.
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|                     // used to result in complete fail, but we'll reset
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|                     $mState = 0;
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|                     $mUcs4  = 0;
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|                     $mBytes = 1;
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|                     $char ='';
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|                 }
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|             }
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|         }
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|         return $out;
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|     }
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| 
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|     /**
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|      * Translates a Unicode codepoint into its corresponding UTF-8 character.
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|      * @note Based on Feyd's function at
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|      *       <http://forums.devnetwork.net/viewtopic.php?p=191404#191404>,
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|      *       which is in public domain.
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|      * @note While we're going to do code point parsing anyway, a good
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|      *       optimization would be to refuse to translate code points that
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|      *       are non-SGML characters.  However, this could lead to duplication.
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|      * @note This is very similar to the unichr function in
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|      *       maintenance/generate-entity-file.php (although this is superior,
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|      *       due to its sanity checks).
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|      */
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| 
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|     // +----------+----------+----------+----------+
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|     // | 33222222 | 22221111 | 111111   |          |
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|     // | 10987654 | 32109876 | 54321098 | 76543210 | bit
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|     // +----------+----------+----------+----------+
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|     // |          |          |          | 0xxxxxxx | 1 byte 0x00000000..0x0000007F
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|     // |          |          | 110yyyyy | 10xxxxxx | 2 byte 0x00000080..0x000007FF
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|     // |          | 1110zzzz | 10yyyyyy | 10xxxxxx | 3 byte 0x00000800..0x0000FFFF
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|     // | 11110www | 10wwzzzz | 10yyyyyy | 10xxxxxx | 4 byte 0x00010000..0x0010FFFF
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|     // +----------+----------+----------+----------+
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|     // | 00000000 | 00011111 | 11111111 | 11111111 | Theoretical upper limit of legal scalars: 2097151 (0x001FFFFF)
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|     // | 00000000 | 00010000 | 11111111 | 11111111 | Defined upper limit of legal scalar codes
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|     // +----------+----------+----------+----------+
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| 
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|     public static function unichr($code)
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|     {
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|         if ($code > 1114111 or $code < 0 or
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|           ($code >= 55296 and $code <= 57343) ) {
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|             // bits are set outside the "valid" range as defined
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|             // by UNICODE 4.1.0
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|             return '';
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|         }
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| 
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|         $x = $y = $z = $w = 0;
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|         if ($code < 128) {
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|             // regular ASCII character
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|             $x = $code;
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|         } else {
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|             // set up bits for UTF-8
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|             $x = ($code & 63) | 128;
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|             if ($code < 2048) {
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|                 $y = (($code & 2047) >> 6) | 192;
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|             } else {
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|                 $y = (($code & 4032) >> 6) | 128;
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|                 if ($code < 65536) {
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|                     $z = (($code >> 12) & 15) | 224;
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|                 } else {
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|                     $z = (($code >> 12) & 63) | 128;
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|                     $w = (($code >> 18) & 7)  | 240;
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|                 }
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|             }
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|         }
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|         // set up the actual character
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|         $ret = '';
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|         if ($w) {
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|             $ret .= chr($w);
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|         }
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|         if ($z) {
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|             $ret .= chr($z);
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|         }
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|         if ($y) {
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|             $ret .= chr($y);
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|         }
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|         $ret .= chr($x);
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| 
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|         return $ret;
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|     }
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| 
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|     /**
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|      * @return bool
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|      */
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|     public static function iconvAvailable()
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|     {
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|         static $iconv = null;
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|         if ($iconv === null) {
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|             $iconv = function_exists('iconv') && self::testIconvTruncateBug() != self::ICONV_UNUSABLE;
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|         }
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|         return $iconv;
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|     }
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| 
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|     /**
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|      * Convert a string to UTF-8 based on configuration.
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|      * @param string $str The string to convert
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|      * @param HTMLPurifier_Config $config
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|      * @param HTMLPurifier_Context $context
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|      * @return string
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|      */
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|     public static function convertToUTF8($str, $config, $context)
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|     {
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|         $encoding = $config->get('Core.Encoding');
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|         if ($encoding === 'utf-8') {
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|             return $str;
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|         }
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|         static $iconv = null;
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|         if ($iconv === null) {
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|             $iconv = self::iconvAvailable();
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|         }
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|         if ($iconv && !$config->get('Test.ForceNoIconv')) {
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|             // unaffected by bugs, since UTF-8 support all characters
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|             $str = self::unsafeIconv($encoding, 'utf-8//IGNORE', $str);
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|             if ($str === false) {
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|                 // $encoding is not a valid encoding
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|                 trigger_error('Invalid encoding ' . $encoding, E_USER_ERROR);
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|                 return '';
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|             }
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|             // If the string is bjorked by Shift_JIS or a similar encoding
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|             // that doesn't support all of ASCII, convert the naughty
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|             // characters to their true byte-wise ASCII/UTF-8 equivalents.
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|             $str = strtr($str, self::testEncodingSupportsASCII($encoding));
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|             return $str;
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|         } elseif ($encoding === 'iso-8859-1') {
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|             $str = utf8_encode($str);
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|             return $str;
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|         }
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|         $bug = HTMLPurifier_Encoder::testIconvTruncateBug();
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|         if ($bug == self::ICONV_OK) {
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|             trigger_error('Encoding not supported, please install iconv', E_USER_ERROR);
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|         } else {
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|             trigger_error(
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|                 'You have a buggy version of iconv, see https://bugs.php.net/bug.php?id=48147 ' .
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|                 'and http://sourceware.org/bugzilla/show_bug.cgi?id=13541',
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|                 E_USER_ERROR
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|             );
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|         }
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|     }
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| 
 | |
|     /**
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|      * Converts a string from UTF-8 based on configuration.
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|      * @param string $str The string to convert
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|      * @param HTMLPurifier_Config $config
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|      * @param HTMLPurifier_Context $context
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|      * @return string
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|      * @note Currently, this is a lossy conversion, with unexpressable
 | |
|      *       characters being omitted.
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|      */
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|     public static function convertFromUTF8($str, $config, $context)
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|     {
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|         $encoding = $config->get('Core.Encoding');
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|         if ($escape = $config->get('Core.EscapeNonASCIICharacters')) {
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|             $str = self::convertToASCIIDumbLossless($str);
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|         }
 | |
|         if ($encoding === 'utf-8') {
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|             return $str;
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|         }
 | |
|         static $iconv = null;
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|         if ($iconv === null) {
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|             $iconv = self::iconvAvailable();
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|         }
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|         if ($iconv && !$config->get('Test.ForceNoIconv')) {
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|             // Undo our previous fix in convertToUTF8, otherwise iconv will barf
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|             $ascii_fix = self::testEncodingSupportsASCII($encoding);
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|             if (!$escape && !empty($ascii_fix)) {
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|                 $clear_fix = array();
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|                 foreach ($ascii_fix as $utf8 => $native) {
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|                     $clear_fix[$utf8] = '';
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|                 }
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|                 $str = strtr($str, $clear_fix);
 | |
|             }
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|             $str = strtr($str, array_flip($ascii_fix));
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|             // Normal stuff
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|             $str = self::iconv('utf-8', $encoding . '//IGNORE', $str);
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|             return $str;
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|         } elseif ($encoding === 'iso-8859-1') {
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|             $str = utf8_decode($str);
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|             return $str;
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|         }
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|         trigger_error('Encoding not supported', E_USER_ERROR);
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|         // You might be tempted to assume that the ASCII representation
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|         // might be OK, however, this is *not* universally true over all
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|         // encodings.  So we take the conservative route here, rather
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|         // than forcibly turn on %Core.EscapeNonASCIICharacters
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|     }
 | |
| 
 | |
|     /**
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|      * Lossless (character-wise) conversion of HTML to ASCII
 | |
|      * @param string $str UTF-8 string to be converted to ASCII
 | |
|      * @return string ASCII encoded string with non-ASCII character entity-ized
 | |
|      * @warning Adapted from MediaWiki, claiming fair use: this is a common
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|      *       algorithm. If you disagree with this license fudgery,
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|      *       implement it yourself.
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|      * @note Uses decimal numeric entities since they are best supported.
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|      * @note This is a DUMB function: it has no concept of keeping
 | |
|      *       character entities that the projected character encoding
 | |
|      *       can allow. We could possibly implement a smart version
 | |
|      *       but that would require it to also know which Unicode
 | |
|      *       codepoints the charset supported (not an easy task).
 | |
|      * @note Sort of with cleanUTF8() but it assumes that $str is
 | |
|      *       well-formed UTF-8
 | |
|      */
 | |
|     public static function convertToASCIIDumbLossless($str)
 | |
|     {
 | |
|         $bytesleft = 0;
 | |
|         $result = '';
 | |
|         $working = 0;
 | |
|         $len = strlen($str);
 | |
|         for ($i = 0; $i < $len; $i++) {
 | |
|             $bytevalue = ord($str[$i]);
 | |
|             if ($bytevalue <= 0x7F) { //0xxx xxxx
 | |
|                 $result .= chr($bytevalue);
 | |
|                 $bytesleft = 0;
 | |
|             } elseif ($bytevalue <= 0xBF) { //10xx xxxx
 | |
|                 $working = $working << 6;
 | |
|                 $working += ($bytevalue & 0x3F);
 | |
|                 $bytesleft--;
 | |
|                 if ($bytesleft <= 0) {
 | |
|                     $result .= "&#" . $working . ";";
 | |
|                 }
 | |
|             } elseif ($bytevalue <= 0xDF) { //110x xxxx
 | |
|                 $working = $bytevalue & 0x1F;
 | |
|                 $bytesleft = 1;
 | |
|             } elseif ($bytevalue <= 0xEF) { //1110 xxxx
 | |
|                 $working = $bytevalue & 0x0F;
 | |
|                 $bytesleft = 2;
 | |
|             } else { //1111 0xxx
 | |
|                 $working = $bytevalue & 0x07;
 | |
|                 $bytesleft = 3;
 | |
|             }
 | |
|         }
 | |
|         return $result;
 | |
|     }
 | |
| 
 | |
|     /** No bugs detected in iconv. */
 | |
|     const ICONV_OK = 0;
 | |
| 
 | |
|     /** Iconv truncates output if converting from UTF-8 to another
 | |
|      *  character set with //IGNORE, and a non-encodable character is found */
 | |
|     const ICONV_TRUNCATES = 1;
 | |
| 
 | |
|     /** Iconv does not support //IGNORE, making it unusable for
 | |
|      *  transcoding purposes */
 | |
|     const ICONV_UNUSABLE = 2;
 | |
| 
 | |
|     /**
 | |
|      * glibc iconv has a known bug where it doesn't handle the magic
 | |
|      * //IGNORE stanza correctly.  In particular, rather than ignore
 | |
|      * characters, it will return an EILSEQ after consuming some number
 | |
|      * of characters, and expect you to restart iconv as if it were
 | |
|      * an E2BIG.  Old versions of PHP did not respect the errno, and
 | |
|      * returned the fragment, so as a result you would see iconv
 | |
|      * mysteriously truncating output. We can work around this by
 | |
|      * manually chopping our input into segments of about 8000
 | |
|      * characters, as long as PHP ignores the error code.  If PHP starts
 | |
|      * paying attention to the error code, iconv becomes unusable.
 | |
|      *
 | |
|      * @return int Error code indicating severity of bug.
 | |
|      */
 | |
|     public static function testIconvTruncateBug()
 | |
|     {
 | |
|         static $code = null;
 | |
|         if ($code === null) {
 | |
|             // better not use iconv, otherwise infinite loop!
 | |
|             $r = self::unsafeIconv('utf-8', 'ascii//IGNORE', "\xCE\xB1" . str_repeat('a', 9000));
 | |
|             if ($r === false) {
 | |
|                 $code = self::ICONV_UNUSABLE;
 | |
|             } elseif (($c = strlen($r)) < 9000) {
 | |
|                 $code = self::ICONV_TRUNCATES;
 | |
|             } elseif ($c > 9000) {
 | |
|                 trigger_error(
 | |
|                     'Your copy of iconv is extremely buggy. Please notify HTML Purifier maintainers: ' .
 | |
|                     'include your iconv version as per phpversion()',
 | |
|                     E_USER_ERROR
 | |
|                 );
 | |
|             } else {
 | |
|                 $code = self::ICONV_OK;
 | |
|             }
 | |
|         }
 | |
|         return $code;
 | |
|     }
 | |
| 
 | |
|     /**
 | |
|      * This expensive function tests whether or not a given character
 | |
|      * encoding supports ASCII. 7/8-bit encodings like Shift_JIS will
 | |
|      * fail this test, and require special processing. Variable width
 | |
|      * encodings shouldn't ever fail.
 | |
|      *
 | |
|      * @param string $encoding Encoding name to test, as per iconv format
 | |
|      * @param bool $bypass Whether or not to bypass the precompiled arrays.
 | |
|      * @return Array of UTF-8 characters to their corresponding ASCII,
 | |
|      *      which can be used to "undo" any overzealous iconv action.
 | |
|      */
 | |
|     public static function testEncodingSupportsASCII($encoding, $bypass = false)
 | |
|     {
 | |
|         // All calls to iconv here are unsafe, proof by case analysis:
 | |
|         // If ICONV_OK, no difference.
 | |
|         // If ICONV_TRUNCATE, all calls involve one character inputs,
 | |
|         // so bug is not triggered.
 | |
|         // If ICONV_UNUSABLE, this call is irrelevant
 | |
|         static $encodings = array();
 | |
|         if (!$bypass) {
 | |
|             if (isset($encodings[$encoding])) {
 | |
|                 return $encodings[$encoding];
 | |
|             }
 | |
|             $lenc = strtolower($encoding);
 | |
|             switch ($lenc) {
 | |
|                 case 'shift_jis':
 | |
|                     return array("\xC2\xA5" => '\\', "\xE2\x80\xBE" => '~');
 | |
|                 case 'johab':
 | |
|                     return array("\xE2\x82\xA9" => '\\');
 | |
|             }
 | |
|             if (strpos($lenc, 'iso-8859-') === 0) {
 | |
|                 return array();
 | |
|             }
 | |
|         }
 | |
|         $ret = array();
 | |
|         if (self::unsafeIconv('UTF-8', $encoding, 'a') === false) {
 | |
|             return false;
 | |
|         }
 | |
|         for ($i = 0x20; $i <= 0x7E; $i++) { // all printable ASCII chars
 | |
|             $c = chr($i); // UTF-8 char
 | |
|             $r = self::unsafeIconv('UTF-8', "$encoding//IGNORE", $c); // initial conversion
 | |
|             if ($r === '' ||
 | |
|                 // This line is needed for iconv implementations that do not
 | |
|                 // omit characters that do not exist in the target character set
 | |
|                 ($r === $c && self::unsafeIconv($encoding, 'UTF-8//IGNORE', $r) !== $c)
 | |
|             ) {
 | |
|                 // Reverse engineer: what's the UTF-8 equiv of this byte
 | |
|                 // sequence? This assumes that there's no variable width
 | |
|                 // encoding that doesn't support ASCII.
 | |
|                 $ret[self::unsafeIconv($encoding, 'UTF-8//IGNORE', $c)] = $c;
 | |
|             }
 | |
|         }
 | |
|         $encodings[$encoding] = $ret;
 | |
|         return $ret;
 | |
|     }
 | |
| }
 | |
| 
 | |
| // vim: et sw=4 sts=4
 |