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   1  <?php
   2  
   3  /*
   4   * Copyright (C) 2016 Nicolas Grekas - p@tchwork.com
   5   *
   6   * This library is free software; you can redistribute it and/or modify it
   7   * under the terms of the (at your option):
   8   * Apache License v2.0 (http://apache.org/licenses/LICENSE-2.0.txt), or
   9   * GNU General Public License v2.0 (http://gnu.org/licenses/gpl-2.0.txt).
  10   */
  11  
  12  namespace Patchwork\PHP\Shim;
  13  
  14  /**
  15   * iconv implementation in pure PHP, UTF-8 centric.
  16   *
  17   * Implemented:
  18   * - iconv              - Convert string to requested character encoding
  19   * - iconv_mime_decode  - Decodes a MIME header field
  20   * - iconv_mime_decode_headers - Decodes multiple MIME header fields at once
  21   * - iconv_get_encoding - Retrieve internal configuration variables of iconv extension
  22   * - iconv_set_encoding - Set current setting for character encoding conversion
  23   * - iconv_mime_encode  - Composes a MIME header field
  24   * - ob_iconv_handler   - Convert character encoding as output buffer handler
  25   * - iconv_strlen       - Returns the character count of string
  26   * - iconv_strpos       - Finds position of first occurrence of a needle within a haystack
  27   * - iconv_strrpos      - Finds the last occurrence of a needle within a haystack
  28   * - iconv_substr       - Cut out part of a string
  29   *
  30   * Charsets available for conversion are defined by files
  31   * in the charset/ directory and by Iconv::$alias below.
  32   * You're welcome to send back any addition you make.
  33   *
  34   * @internal
  35   */
  36  class Iconv
  37  {
  38      const ERROR_ILLEGAL_CHARACTER = 'iconv(): Detected an illegal character in input string';
  39      const ERROR_WRONG_CHARSET = 'iconv(): Wrong charset, conversion from `%s\' to `%s\' is not allowed';
  40  
  41      public static $inputEncoding = 'utf-8';
  42      public static $outputEncoding = 'utf-8';
  43      public static $internalEncoding = 'utf-8';
  44  
  45      private static $alias = array(
  46          'utf8' => 'utf-8',
  47          'ascii' => 'us-ascii',
  48          'tis-620' => 'iso-8859-11',
  49          'cp1250' => 'windows-1250',
  50          'cp1251' => 'windows-1251',
  51          'cp1252' => 'windows-1252',
  52          'cp1253' => 'windows-1253',
  53          'cp1254' => 'windows-1254',
  54          'cp1255' => 'windows-1255',
  55          'cp1256' => 'windows-1256',
  56          'cp1257' => 'windows-1257',
  57          'cp1258' => 'windows-1258',
  58          'shift-jis' => 'cp932',
  59          'shift_jis' => 'cp932',
  60          'latin1' => 'iso-8859-1',
  61          'latin2' => 'iso-8859-2',
  62          'latin3' => 'iso-8859-3',
  63          'latin4' => 'iso-8859-4',
  64          'latin5' => 'iso-8859-9',
  65          'latin6' => 'iso-8859-10',
  66          'latin7' => 'iso-8859-13',
  67          'latin8' => 'iso-8859-14',
  68          'latin9' => 'iso-8859-15',
  69          'latin10' => 'iso-8859-16',
  70          'iso8859-1' => 'iso-8859-1',
  71          'iso8859-2' => 'iso-8859-2',
  72          'iso8859-3' => 'iso-8859-3',
  73          'iso8859-4' => 'iso-8859-4',
  74          'iso8859-5' => 'iso-8859-5',
  75          'iso8859-6' => 'iso-8859-6',
  76          'iso8859-7' => 'iso-8859-7',
  77          'iso8859-8' => 'iso-8859-8',
  78          'iso8859-9' => 'iso-8859-9',
  79          'iso8859-10' => 'iso-8859-10',
  80          'iso8859-11' => 'iso-8859-11',
  81          'iso8859-12' => 'iso-8859-12',
  82          'iso8859-13' => 'iso-8859-13',
  83          'iso8859-14' => 'iso-8859-14',
  84          'iso8859-15' => 'iso-8859-15',
  85          'iso8859-16' => 'iso-8859-16',
  86          'iso_8859-1' => 'iso-8859-1',
  87          'iso_8859-2' => 'iso-8859-2',
  88          'iso_8859-3' => 'iso-8859-3',
  89          'iso_8859-4' => 'iso-8859-4',
  90          'iso_8859-5' => 'iso-8859-5',
  91          'iso_8859-6' => 'iso-8859-6',
  92          'iso_8859-7' => 'iso-8859-7',
  93          'iso_8859-8' => 'iso-8859-8',
  94          'iso_8859-9' => 'iso-8859-9',
  95          'iso_8859-10' => 'iso-8859-10',
  96          'iso_8859-11' => 'iso-8859-11',
  97          'iso_8859-12' => 'iso-8859-12',
  98          'iso_8859-13' => 'iso-8859-13',
  99          'iso_8859-14' => 'iso-8859-14',
 100          'iso_8859-15' => 'iso-8859-15',
 101          'iso_8859-16' => 'iso-8859-16',
 102          'iso88591' => 'iso-8859-1',
 103          'iso88592' => 'iso-8859-2',
 104          'iso88593' => 'iso-8859-3',
 105          'iso88594' => 'iso-8859-4',
 106          'iso88595' => 'iso-8859-5',
 107          'iso88596' => 'iso-8859-6',
 108          'iso88597' => 'iso-8859-7',
 109          'iso88598' => 'iso-8859-8',
 110          'iso88599' => 'iso-8859-9',
 111          'iso885910' => 'iso-8859-10',
 112          'iso885911' => 'iso-8859-11',
 113          'iso885912' => 'iso-8859-12',
 114          'iso885913' => 'iso-8859-13',
 115          'iso885914' => 'iso-8859-14',
 116          'iso885915' => 'iso-8859-15',
 117          'iso885916' => 'iso-8859-16',
 118      );
 119      private static $translitMap = array();
 120      private static $convertMap = array();
 121      private static $errorHandler;
 122      private static $lastError;
 123  
 124      private static $ulenMask = array("\xC0" => 2, "\xD0" => 2, "\xE0" => 3, "\xF0" => 4);
 125      private static $isValidUtf8;
 126  
 127      public static function iconv($inCharset, $outCharset, $str)
 128      {
 129          if ('' === $str .= '') {
 130              return '';
 131          }
 132  
 133          // Prepare for //IGNORE and //TRANSLIT
 134  
 135          $translit = $ignore = '';
 136  
 137          $outCharset = strtolower($outCharset);
 138          $inCharset = strtolower($inCharset);
 139  
 140          if ('' === $outCharset) {
 141              $outCharset = 'iso-8859-1';
 142          }
 143          if ('' === $inCharset) {
 144              $inCharset = 'iso-8859-1';
 145          }
 146  
 147          if ('//translit' === substr($outCharset, -10)) {
 148              $translit = '//TRANSLIT';
 149              $outCharset = substr($outCharset, 0, -10);
 150          }
 151  
 152          if ('//ignore' === substr($outCharset, -8)) {
 153              $ignore = '//IGNORE';
 154              $outCharset = substr($outCharset, 0, -8);
 155          }
 156  
 157          if ('//translit' === substr($inCharset, -10)) {
 158              $inCharset = substr($inCharset, 0, -10);
 159          }
 160          if ('//ignore' === substr($inCharset, -8)) {
 161              $inCharset = substr($inCharset, 0, -8);
 162          }
 163  
 164          if (isset(self::$alias[ $inCharset])) {
 165              $inCharset = self::$alias[ $inCharset];
 166          }
 167          if (isset(self::$alias[$outCharset])) {
 168              $outCharset = self::$alias[$outCharset];
 169          }
 170  
 171          // Load charset maps
 172  
 173          if (('utf-8' !== $inCharset && !self::loadMap('from.', $inCharset, $inMap))
 174            || ('utf-8' !== $outCharset && !self::loadMap('to.', $outCharset, $outMap))) {
 175              trigger_error(sprintf(self::ERROR_WRONG_CHARSET, $inCharset, $outCharset));
 176  
 177              return false;
 178          }
 179  
 180          if ('utf-8' !== $inCharset) {
 181              // Convert input to UTF-8
 182              $result = '';
 183              if (self::mapToUtf8($result, $inMap, $str, $ignore)) {
 184                  $str = $result;
 185              } else {
 186                  $str = false;
 187              }
 188              self::$isValidUtf8 = true;
 189          } else {
 190              self::$isValidUtf8 = preg_match('//u', $str);
 191  
 192              if (!self::$isValidUtf8 && !$ignore) {
 193                  trigger_error(self::ERROR_ILLEGAL_CHARACTER);
 194  
 195                  return false;
 196              }
 197  
 198              if ('utf-8' === $outCharset) {
 199                  // UTF-8 validation
 200                  $str = self::utf8ToUtf8($str, $ignore);
 201              }
 202          }
 203  
 204          if ('utf-8' !== $outCharset && false !== $str) {
 205              // Convert output to UTF-8
 206              $result = '';
 207              if (self::mapFromUtf8($result, $outMap, $str, $ignore, $translit)) {
 208                  return $result;
 209              }
 210  
 211              return false;
 212          }
 213  
 214          return $str;
 215      }
 216  
 217      public static function iconv_mime_decode_headers($str, $mode = 0, $charset = null)
 218      {
 219          if (null === $charset) {
 220              $charset = self::$internalEncoding;
 221          }
 222  
 223          if (false !== strpos($str, "\r")) {
 224              $str = strtr(str_replace("\r\n", "\n", $str), "\r", "\n");
 225          }
 226          $str = explode("\n\n", $str, 2);
 227  
 228          $headers = array();
 229  
 230          $str = preg_split('/\n(?![ \t])/', $str[0]);
 231          foreach ($str as $str) {
 232              $str = self::iconv_mime_decode($str, $mode, $charset);
 233              if (false === $str) {
 234                  return false;
 235              }
 236              $str = explode(':', $str, 2);
 237  
 238              if (2 === count($str)) {
 239                  if (isset($headers[$str[0]])) {
 240                      if (!is_array($headers[$str[0]])) {
 241                          $headers[$str[0]] = array($headers[$str[0]]);
 242                      }
 243                      $headers[$str[0]][] = ltrim($str[1]);
 244                  } else {
 245                      $headers[$str[0]] = ltrim($str[1]);
 246                  }
 247              }
 248          }
 249  
 250          return $headers;
 251      }
 252  
 253      public static function iconv_mime_decode($str, $mode = 0, $charset = null)
 254      {
 255          if (null === $charset) {
 256              $charset = self::$internalEncoding;
 257          }
 258          if (ICONV_MIME_DECODE_CONTINUE_ON_ERROR & $mode) {
 259              $charset .= '//IGNORE';
 260          }
 261  
 262          if (false !== strpos($str, "\r")) {
 263              $str = strtr(str_replace("\r\n", "\n", $str), "\r", "\n");
 264          }
 265          $str = preg_split('/\n(?![ \t])/', rtrim($str), 2);
 266          $str = preg_replace('/[ \t]*\n[ \t]+/', ' ', rtrim($str[0]));
 267          $str = preg_split('/=\?([^?]+)\?([bqBQ])\?(.*?)\?=/', $str, -1, PREG_SPLIT_DELIM_CAPTURE);
 268  
 269          $result = self::iconv('utf-8', $charset, $str[0]);
 270          if (false === $result) {
 271              return false;
 272          }
 273  
 274          $i = 1;
 275          $len = count($str);
 276  
 277          while ($i < $len) {
 278              $c = strtolower($str[$i]);
 279              if ((ICONV_MIME_DECODE_CONTINUE_ON_ERROR & $mode)
 280                && 'utf-8' !== $c
 281                && !isset(self::$alias[$c])
 282                && !self::loadMap('from.', $c,  $d)) {
 283                  $d = false;
 284              } elseif ('B' === strtoupper($str[$i + 1])) {
 285                  $d = base64_decode($str[$i + 2]);
 286              } else {
 287                  $d = rawurldecode(strtr(str_replace('%', '%25', $str[$i + 2]), '=_', '% '));
 288              }
 289  
 290              if (false !== $d) {
 291                  if ('' !== $d) {
 292                      if ('' === $d = self::iconv($c, $charset, $d)) {
 293                          $str[$i + 3] = substr($str[$i + 3], 1);
 294                      } else {
 295                          $result .= $d;
 296                      }
 297                  }
 298                  $d = self::iconv('utf-8', $charset, $str[$i + 3]);
 299                  if ('' !== trim($d)) {
 300                      $result .= $d;
 301                  }
 302              } elseif (ICONV_MIME_DECODE_CONTINUE_ON_ERROR & $mode) {
 303                  $result .= "=?{$str[$i]}?{$str[$i + 1]}?{$str[$i + 2]}?={$str[$i + 3]}";
 304              } else {
 305                  $result = false;
 306                  break;
 307              }
 308  
 309              $i += 4;
 310          }
 311  
 312          return $result;
 313      }
 314  
 315      public static function iconv_get_encoding($type = 'all')
 316      {
 317          switch ($type) {
 318              case 'input_encoding': return self::$inputEncoding;
 319              case 'output_encoding': return self::$outputEncoding;
 320              case 'internal_encoding': return self::$internalEncoding;
 321          }
 322  
 323          return array(
 324              'input_encoding' => self::$inputEncoding,
 325              'output_encoding' => self::$outputEncoding,
 326              'internal_encoding' => self::$internalEncoding,
 327          );
 328      }
 329  
 330      public static function iconv_set_encoding($type, $charset)
 331      {
 332          switch ($type) {
 333              case 'input_encoding': self::$inputEncoding = $charset; break;
 334              case 'output_encoding': self::$outputEncoding = $charset; break;
 335              case 'internal_encoding': self::$internalEncoding = $charset; break;
 336  
 337              default: return false;
 338          }
 339  
 340          return true;
 341      }
 342  
 343      public static function iconv_mime_encode($fieldName, $fieldValue, $pref = null)
 344      {
 345          if (!is_array($pref)) {
 346              $pref = array();
 347          }
 348  
 349          $pref += array(
 350              'scheme' => 'B',
 351              'input-charset' => self::$internalEncoding,
 352              'output-charset' => self::$internalEncoding,
 353              'line-length' => 76,
 354              'line-break-chars' => "\r\n",
 355          );
 356  
 357          if (preg_match('/[\x80-\xFF]/', $fieldName)) {
 358              $fieldName = '';
 359          }
 360  
 361          $scheme = strtoupper(substr($pref['scheme'], 0, 1));
 362          $in = strtolower($pref['input-charset']);
 363          $out = strtolower($pref['output-charset']);
 364  
 365          if ('utf-8' !== $in && false === $fieldValue = self::iconv($in, 'utf-8', $fieldValue)) {
 366              return false;
 367          }
 368  
 369          preg_match_all('/./us', $fieldValue, $chars);
 370  
 371          $chars = isset($chars[0]) ? $chars[0] : array();
 372  
 373          $lineBreak = (int) $pref['line-length'];
 374          $lineStart = "=?{$pref['output-charset']}?{$scheme}?";
 375          $lineLength = strlen($fieldName) + 2 + strlen($lineStart) + 2;
 376          $lineOffset = strlen($lineStart) + 3;
 377          $lineData = '';
 378  
 379          $fieldValue = array();
 380  
 381          $Q = 'Q' === $scheme;
 382  
 383          foreach ($chars as $c) {
 384              if ('utf-8' !== $out && false === $c = self::iconv('utf-8', $out, $c)) {
 385                  return false;
 386              }
 387  
 388              $o = $Q
 389                  ? $c = preg_replace_callback(
 390                      '/[=_\?\x00-\x1F\x80-\xFF]/',
 391                      array(__CLASS__, 'qpByteCallback'),
 392                      $c
 393                  )
 394                  : base64_encode($lineData.$c);
 395  
 396              if (isset($o[$lineBreak - $lineLength])) {
 397                  if (!$Q) {
 398                      $lineData = base64_encode($lineData);
 399                  }
 400                  $fieldValue[] = $lineStart.$lineData.'?=';
 401                  $lineLength = $lineOffset;
 402                  $lineData = '';
 403              }
 404  
 405              $lineData .= $c;
 406              $Q && $lineLength += strlen($c);
 407          }
 408  
 409          if ('' !== $lineData) {
 410              if (!$Q) {
 411                  $lineData = base64_encode($lineData);
 412              }
 413              $fieldValue[] = $lineStart.$lineData.'?=';
 414          }
 415  
 416          return $fieldName.': '.implode($pref['line-break-chars'].' ', $fieldValue);
 417      }
 418  
 419      public static function ob_iconv_handler($buffer, $mode)
 420      {
 421          return self::iconv(self::$internalEncoding, self::$outputEncoding, $buffer);
 422      }
 423  
 424      public static function iconv_strlen($s, $encoding = null)
 425      {
 426          static $hasXml = null;
 427          if (null === $hasXml) {
 428              $hasXml = extension_loaded('xml');
 429          }
 430  
 431          if ($hasXml) {
 432              return self::strlen1($s, $encoding);
 433          }
 434  
 435          return self::strlen2($s, $encoding);
 436      }
 437  
 438      public static function strlen1($s, $encoding = null)
 439      {
 440          if (null === $encoding) {
 441              $encoding = self::$internalEncoding;
 442          }
 443          if (0 !== stripos($encoding, 'utf-8') && false === $s = self::iconv($encoding, 'utf-8', $s)) {
 444              return false;
 445          }
 446  
 447          return strlen(utf8_decode($s));
 448      }
 449  
 450      public static function strlen2($s, $encoding = null)
 451      {
 452          if (null === $encoding) {
 453              $encoding = self::$internalEncoding;
 454          }
 455          if (0 !== stripos($encoding, 'utf-8') && false === $s = self::iconv($encoding, 'utf-8', $s)) {
 456              return false;
 457          }
 458  
 459          $ulenMask = self::$ulenMask;
 460  
 461          $i = 0;
 462          $j = 0;
 463          $len = strlen($s);
 464  
 465          while ($i < $len) {
 466              $u = $s[$i] & "\xF0";
 467              $i += isset($ulenMask[$u]) ? $ulenMask[$u] : 1;
 468              ++$j;
 469          }
 470  
 471          return $j;
 472      }
 473  
 474      public static function iconv_strpos($haystack, $needle, $offset = 0, $encoding = null)
 475      {
 476          if (null === $encoding) {
 477              $encoding = self::$internalEncoding;
 478          }
 479  
 480          if (0 !== stripos($encoding, 'utf-8')) {
 481              if (false === $haystack = self::iconv($encoding, 'utf-8', $haystack)) {
 482                  return false;
 483              }
 484              if (false === $needle = self::iconv($encoding, 'utf-8', $needle)) {
 485                  return false;
 486              }
 487          }
 488  
 489          if ($offset = (int) $offset) {
 490              $haystack = self::iconv_substr($haystack, $offset, 2147483647, 'utf-8');
 491          }
 492          $pos = strpos($haystack, $needle);
 493  
 494          return false === $pos ? false : ($offset + ($pos ? self::iconv_strlen(substr($haystack, 0, $pos), 'utf-8') : 0));
 495      }
 496  
 497      public static function iconv_strrpos($haystack, $needle, $encoding = null)
 498      {
 499          if (null === $encoding) {
 500              $encoding = self::$internalEncoding;
 501          }
 502  
 503          if (0 !== stripos($encoding, 'utf-8')) {
 504              if (false === $haystack = self::iconv($encoding, 'utf-8', $haystack)) {
 505                  return false;
 506              }
 507              if (false === $needle = self::iconv($encoding, 'utf-8', $needle)) {
 508                  return false;
 509              }
 510          }
 511  
 512          $pos = isset($needle[0]) ? strrpos($haystack, $needle) : false;
 513  
 514          return false === $pos ? false : self::iconv_strlen($pos ? substr($haystack, 0, $pos) : $haystack, 'utf-8');
 515      }
 516  
 517      public static function iconv_substr($s, $start, $length = 2147483647, $encoding = null)
 518      {
 519          if (null === $encoding) {
 520              $encoding = self::$internalEncoding;
 521          }
 522          if (0 !== stripos($encoding, 'utf-8')) {
 523              $encoding = null;
 524          } elseif (false === $s = self::iconv($encoding, 'utf-8', $s)) {
 525              return false;
 526          }
 527  
 528          $s .= '';
 529          $slen = self::iconv_strlen($s, 'utf-8');
 530          $start = (int) $start;
 531  
 532          if (0 > $start) {
 533              $start += $slen;
 534          }
 535          if (0 > $start) {
 536              return false;
 537          }
 538          if ($start >= $slen) {
 539              return false;
 540          }
 541  
 542          $rx = $slen - $start;
 543  
 544          if (0 > $length) {
 545              $length += $rx;
 546          }
 547          if (0 === $length) {
 548              return '';
 549          }
 550          if (0 > $length) {
 551              return false;
 552          }
 553  
 554          if ($length > $rx) {
 555              $length = $rx;
 556          }
 557  
 558          $rx = '/^'.($start ? self::pregOffset($start) : '').'('.self::pregOffset($length).')/u';
 559  
 560          $s = preg_match($rx, $s, $s) ? $s[1] : '';
 561  
 562          if (null === $encoding) {
 563              return $s;
 564          }
 565  
 566          return self::iconv('utf-8', $encoding, $s);
 567      }
 568  
 569      private static function loadMap($type, $charset, &$map)
 570      {
 571          if (!isset(self::$convertMap[$type.$charset])) {
 572              if (false === $map = self::getData($type.$charset)) {
 573                  if ('to.' === $type && self::loadMap('from.', $charset, $map)) {
 574                      $map = array_flip($map);
 575                  } else {
 576                      return false;
 577                  }
 578              }
 579  
 580              self::$convertMap[$type.$charset] = $map;
 581          } else {
 582              $map = self::$convertMap[$type.$charset];
 583          }
 584  
 585          return true;
 586      }
 587  
 588      private static function utf8ToUtf8($str, $ignore)
 589      {
 590          $ulenMask = self::$ulenMask;
 591          $valid = self::$isValidUtf8;
 592  
 593          $u = $str;
 594          $i = $j = 0;
 595          $len = strlen($str);
 596  
 597          while ($i < $len) {
 598              if ($str[$i] < "\x80") {
 599                  $u[$j++] = $str[$i++];
 600              } else {
 601                  $ulen = $str[$i] & "\xF0";
 602                  $ulen = isset($ulenMask[$ulen]) ? $ulenMask[$ulen] : 1;
 603                  $uchr = substr($str, $i, $ulen);
 604  
 605                  if (1 === $ulen || !($valid || preg_match('/^.$/us', $uchr))) {
 606                      if ($ignore) {
 607                          ++$i;
 608                          continue;
 609                      }
 610  
 611                      trigger_error(self::ERROR_ILLEGAL_CHARACTER);
 612  
 613                      return false;
 614                  } else {
 615                      $i += $ulen;
 616                  }
 617  
 618                  $u[$j++] = $uchr[0];
 619  
 620                  isset($uchr[1]) && 0 !== ($u[$j++] = $uchr[1])
 621                      && isset($uchr[2]) && 0 !== ($u[$j++] = $uchr[2])
 622                      && isset($uchr[3]) && 0 !== ($u[$j++] = $uchr[3]);
 623              }
 624          }
 625  
 626          return substr($u, 0, $j);
 627      }
 628  
 629      private static function mapToUtf8(&$result, $map, $str, $ignore)
 630      {
 631          $len = strlen($str);
 632          for ($i = 0; $i < $len; ++$i) {
 633              if (isset($str[$i + 1], $map[$str[$i].$str[$i + 1]])) {
 634                  $result .= $map[$str[$i].$str[++$i]];
 635              } elseif (isset($map[$str[$i]])) {
 636                  $result .= $map[$str[$i]];
 637              } elseif (!$ignore) {
 638                  trigger_error(self::ERROR_ILLEGAL_CHARACTER);
 639  
 640                  return false;
 641              }
 642          }
 643  
 644          return true;
 645      }
 646  
 647      private static function mapFromUtf8(&$result, $map, $str, $ignore, $translit)
 648      {
 649          $ulenMask = self::$ulenMask;
 650          $valid = self::$isValidUtf8;
 651  
 652          if ($translit && !self::$translitMap) {
 653              self::$translitMap = self::getData('translit');
 654          }
 655  
 656          $i = 0;
 657          $len = strlen($str);
 658  
 659          while ($i < $len) {
 660              if ($str[$i] < "\x80") {
 661                  $uchr = $str[$i++];
 662              } else {
 663                  $ulen = $str[$i] & "\xF0";
 664                  $ulen = isset($ulenMask[$ulen]) ? $ulenMask[$ulen] : 1;
 665                  $uchr = substr($str, $i, $ulen);
 666  
 667                  if ($ignore && (1 === $ulen || !($valid || preg_match('/^.$/us', $uchr)))) {
 668                      ++$i;
 669                      continue;
 670                  } else {
 671                      $i += $ulen;
 672                  }
 673              }
 674  
 675              if (isset($map[$uchr])) {
 676                  $result .= $map[$uchr];
 677              } elseif ($translit) {
 678                  if (isset(self::$translitMap[$uchr])) {
 679                      $uchr = self::$translitMap[$uchr];
 680                  } elseif ($uchr >= "\xC3\x80") {
 681                      $uchr = \Normalizer::normalize($uchr, \Normalizer::NFD);
 682  
 683                      if ($uchr[0] < "\x80") {
 684                          $uchr = $uchr[0];
 685                      } elseif ($ignore) {
 686                          continue;
 687                      } else {
 688                          return false;
 689                      }
 690                  }
 691  
 692                  $str = $uchr.substr($str, $i);
 693                  $len = strlen($str);
 694                  $i = 0;
 695              } elseif (!$ignore) {
 696                  return false;
 697              }
 698          }
 699  
 700          return true;
 701      }
 702  
 703      private static function qpByteCallback($m)
 704      {
 705          return '='.strtoupper(dechex(ord($m[0])));
 706      }
 707  
 708      private static function pregOffset($offset)
 709      {
 710          $rx = array();
 711          $offset = (int) $offset;
 712  
 713          while ($offset > 65535) {
 714              $rx[] = '.{65535}';
 715              $offset -= 65535;
 716          }
 717  
 718          return implode('', $rx).'.{'.$offset.'}';
 719      }
 720  
 721      private static function getData($file)
 722      {
 723          if (file_exists($file = __DIR__.'/charset/'.$file.'.ser')) {
 724              return unserialize(file_get_contents($file));
 725          }
 726  
 727          return false;
 728      }
 729  }