summaryrefslogtreecommitdiff
path: root/program/include/rcube_charset.php
diff options
context:
space:
mode:
authorAleksander Machniak <alec@alec.pl>2012-11-21 19:52:03 +0100
committerAleksander Machniak <alec@alec.pl>2012-11-21 19:52:03 +0100
commitba6f21caeb405c7e8512a09941fefbc97286e45f (patch)
tree4a0e8f6fbab3260d37bf85cbf0bc9f506e627678 /program/include/rcube_charset.php
parentf707fec0001d7dc7d46be114c42b37e49a052660 (diff)
Framework files moved to lib/Roundcube
Diffstat (limited to 'program/include/rcube_charset.php')
-rw-r--r--program/include/rcube_charset.php791
1 files changed, 0 insertions, 791 deletions
diff --git a/program/include/rcube_charset.php b/program/include/rcube_charset.php
deleted file mode 100644
index e8cce00e3..000000000
--- a/program/include/rcube_charset.php
+++ /dev/null
@@ -1,791 +0,0 @@
-<?php
-
-/*
- +-----------------------------------------------------------------------+
- | program/include/rcube_charset.php |
- | |
- | This file is part of the Roundcube Webmail client |
- | Copyright (C) 2005-2012, The Roundcube Dev Team |
- | Copyright (C) 2011-2012, Kolab Systems AG |
- | Copyright (C) 2000 Edmund Grimley Evans <edmundo@rano.org> |
- | |
- | Licensed under the GNU General Public License version 3 or |
- | any later version with exceptions for skins & plugins. |
- | See the README file for a full license statement. |
- | |
- | PURPOSE: |
- | Provide charset conversion functionality |
- | |
- +-----------------------------------------------------------------------+
- | Author: Thomas Bruederli <roundcube@gmail.com> |
- | Author: Aleksander Machniak <alec@alec.pl> |
- +-----------------------------------------------------------------------+
-*/
-
-/**
- * Character sets conversion functionality
- *
- * @package Framework
- * @subpackage Core
- * @author Thomas Bruederli <roundcube@gmail.com>
- * @author Aleksander Machniak <alec@alec.pl>
- * @author Edmund Grimley Evans <edmundo@rano.org>
- */
-class rcube_charset
-{
- // Aliases: some of them from HTML5 spec.
- static public $aliases = array(
- 'USASCII' => 'WINDOWS-1252',
- 'ANSIX31101983' => 'WINDOWS-1252',
- 'ANSIX341968' => 'WINDOWS-1252',
- 'UNKNOWN8BIT' => 'ISO-8859-15',
- 'UNKNOWN' => 'ISO-8859-15',
- 'USERDEFINED' => 'ISO-8859-15',
- 'KSC56011987' => 'EUC-KR',
- 'GB2312' => 'GBK',
- 'GB231280' => 'GBK',
- 'UNICODE' => 'UTF-8',
- 'UTF7IMAP' => 'UTF7-IMAP',
- 'TIS620' => 'WINDOWS-874',
- 'ISO88599' => 'WINDOWS-1254',
- 'ISO885911' => 'WINDOWS-874',
- 'MACROMAN' => 'MACINTOSH',
- '77' => 'MAC',
- '128' => 'SHIFT-JIS',
- '129' => 'CP949',
- '130' => 'CP1361',
- '134' => 'GBK',
- '136' => 'BIG5',
- '161' => 'WINDOWS-1253',
- '162' => 'WINDOWS-1254',
- '163' => 'WINDOWS-1258',
- '177' => 'WINDOWS-1255',
- '178' => 'WINDOWS-1256',
- '186' => 'WINDOWS-1257',
- '204' => 'WINDOWS-1251',
- '222' => 'WINDOWS-874',
- '238' => 'WINDOWS-1250',
- 'MS950' => 'CP950',
- 'WINDOWS949' => 'UHC',
- );
-
-
- /**
- * Catch an error and throw an exception.
- *
- * @param int Level of the error
- * @param string Error message
- */
- public static function error_handler($errno, $errstr)
- {
- throw new ErrorException($errstr, 0, $errno);
- }
-
-
- /**
- * Parse and validate charset name string (see #1485758).
- * Sometimes charset string is malformed, there are also charset aliases
- * but we need strict names for charset conversion (specially utf8 class)
- *
- * @param string $input Input charset name
- *
- * @return string The validated charset name
- */
- public static function parse_charset($input)
- {
- static $charsets = array();
- $charset = strtoupper($input);
-
- if (isset($charsets[$input])) {
- return $charsets[$input];
- }
-
- $charset = preg_replace(array(
- '/^[^0-9A-Z]+/', // e.g. _ISO-8859-JP$SIO
- '/\$.*$/', // e.g. _ISO-8859-JP$SIO
- '/UNICODE-1-1-*/', // RFC1641/1642
- '/^X-/', // X- prefix (e.g. X-ROMAN8 => ROMAN8)
- ), '', $charset);
-
- if ($charset == 'BINARY') {
- return $charsets[$input] = null;
- }
-
- // allow A-Z and 0-9 only
- $str = preg_replace('/[^A-Z0-9]/', '', $charset);
-
- if (isset(self::$aliases[$str])) {
- $result = self::$aliases[$str];
- }
- // UTF
- else if (preg_match('/U[A-Z][A-Z](7|8|16|32)(BE|LE)*/', $str, $m)) {
- $result = 'UTF-' . $m[1] . $m[2];
- }
- // ISO-8859
- else if (preg_match('/ISO8859([0-9]{0,2})/', $str, $m)) {
- $iso = 'ISO-8859-' . ($m[1] ? $m[1] : 1);
- // some clients sends windows-1252 text as latin1,
- // it is safe to use windows-1252 for all latin1
- $result = $iso == 'ISO-8859-1' ? 'WINDOWS-1252' : $iso;
- }
- // handle broken charset names e.g. WINDOWS-1250HTTP-EQUIVCONTENT-TYPE
- else if (preg_match('/(WIN|WINDOWS)([0-9]+)/', $str, $m)) {
- $result = 'WINDOWS-' . $m[2];
- }
- // LATIN
- else if (preg_match('/LATIN(.*)/', $str, $m)) {
- $aliases = array('2' => 2, '3' => 3, '4' => 4, '5' => 9, '6' => 10,
- '7' => 13, '8' => 14, '9' => 15, '10' => 16,
- 'ARABIC' => 6, 'CYRILLIC' => 5, 'GREEK' => 7, 'GREEK1' => 7, 'HEBREW' => 8
- );
-
- // some clients sends windows-1252 text as latin1,
- // it is safe to use windows-1252 for all latin1
- if ($m[1] == 1) {
- $result = 'WINDOWS-1252';
- }
- // if iconv is not supported we need ISO labels, it's also safe for iconv
- else if (!empty($aliases[$m[1]])) {
- $result = 'ISO-8859-'.$aliases[$m[1]];
- }
- // iconv requires convertion of e.g. LATIN-1 to LATIN1
- else {
- $result = $str;
- }
- }
- else {
- $result = $charset;
- }
-
- $charsets[$input] = $result;
-
- return $result;
- }
-
-
- /**
- * Convert a string from one charset to another.
- * Uses mbstring and iconv functions if possible
- *
- * @param string Input string
- * @param string Suspected charset of the input string
- * @param string Target charset to convert to; defaults to RCMAIL_CHARSET
- *
- * @return string Converted string
- */
- public static function convert($str, $from, $to = null)
- {
- static $iconv_options = null;
- static $mbstring_list = null;
- static $mbstring_sch = null;
- static $conv = null;
-
- $to = empty($to) ? RCMAIL_CHARSET : $to;
- $from = self::parse_charset($from);
-
- // It is a common case when UTF-16 charset is used with US-ASCII content (#1488654)
- // In that case we can just skip the conversion (use UTF-8)
- if ($from == 'UTF-16' && !preg_match('/[^\x00-\x7F]/', $str)) {
- $from = 'UTF-8';
- }
-
- if ($from == $to || empty($str) || empty($from)) {
- return $str;
- }
-
- if ($iconv_options === null) {
- if (function_exists('iconv')) {
- // ignore characters not available in output charset
- $iconv_options = '//IGNORE';
- if (iconv('', $iconv_options, '') === false) {
- // iconv implementation does not support options
- $iconv_options = '';
- }
- }
- }
-
- // convert charset using iconv module
- if ($iconv_options !== null && $from != 'UTF7-IMAP' && $to != 'UTF7-IMAP') {
- // throw an exception if iconv reports an illegal character in input
- // it means that input string has been truncated
- set_error_handler(array('rcube_charset', 'error_handler'), E_NOTICE);
- try {
- $_iconv = iconv($from, $to . $iconv_options, $str);
- } catch (ErrorException $e) {
- $_iconv = false;
- }
- restore_error_handler();
-
- if ($_iconv !== false) {
- return $_iconv;
- }
- }
-
- if ($mbstring_list === null) {
- if (extension_loaded('mbstring')) {
- $mbstring_sch = mb_substitute_character();
- $mbstring_list = mb_list_encodings();
- $mbstring_list = array_map('strtoupper', $mbstring_list);
- }
- }
-
- // convert charset using mbstring module
- if ($mbstring_list !== null) {
- $aliases['WINDOWS-1257'] = 'ISO-8859-13';
- // it happens that mbstring supports ASCII but not US-ASCII
- if (($from == 'US-ASCII' || $to == 'US-ASCII') && !in_array('US-ASCII', $mbstring_list)) {
- $aliases['US-ASCII'] = 'ASCII';
- }
-
- $mb_from = $aliases[$from] ? $aliases[$from] : $from;
- $mb_to = $aliases[$to] ? $aliases[$to] : $to;
-
- // return if encoding found, string matches encoding and convert succeeded
- if (in_array($mb_from, $mbstring_list) && in_array($mb_to, $mbstring_list)) {
- if (mb_check_encoding($str, $mb_from)) {
- // Do the same as //IGNORE with iconv
- mb_substitute_character('none');
- $out = mb_convert_encoding($str, $mb_to, $mb_from);
- mb_substitute_character($mbstring_sch);
-
- if ($out !== false) {
- return $out;
- }
- }
- }
- }
-
- // convert charset using bundled classes/functions
- if ($to == 'UTF-8') {
- if ($from == 'UTF7-IMAP') {
- if ($_str = self::utf7imap_to_utf8($str)) {
- return $_str;
- }
- }
- else if ($from == 'UTF-7') {
- if ($_str = self::utf7_to_utf8($str)) {
- return $_str;
- }
- }
- else if ($from == 'ISO-8859-1' && function_exists('utf8_encode')) {
- return utf8_encode($str);
- }
- else if (class_exists('utf8')) {
- if (!$conv) {
- $conv = new utf8($from);
- }
- else {
- $conv->loadCharset($from);
- }
-
- if ($_str = $conv->strToUtf8($str)) {
- return $_str;
- }
- }
- }
-
- // encode string for output
- if ($from == 'UTF-8') {
- // @TODO: we need a function for UTF-7 (RFC2152) conversion
- if ($to == 'UTF7-IMAP' || $to == 'UTF-7') {
- if ($_str = self::utf8_to_utf7imap($str)) {
- return $_str;
- }
- }
- else if ($to == 'ISO-8859-1' && function_exists('utf8_decode')) {
- return utf8_decode($str);
- }
- else if (class_exists('utf8')) {
- if (!$conv) {
- $conv = new utf8($to);
- }
- else {
- $conv->loadCharset($from);
- }
-
- if ($_str = $conv->strToUtf8($str)) {
- return $_str;
- }
- }
- }
-
- // return original string
- return $str;
- }
-
-
- /**
- * Converts string from standard UTF-7 (RFC 2152) to UTF-8.
- *
- * @param string Input string (UTF-7)
- *
- * @return string Converted string (UTF-8)
- */
- public static function utf7_to_utf8($str)
- {
- $Index_64 = array(
- 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0,
- 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0,
- 0,0,0,0, 0,0,0,0, 0,0,0,1, 0,0,0,0,
- 1,1,1,1, 1,1,1,1, 1,1,0,0, 0,0,0,0,
- 0,1,1,1, 1,1,1,1, 1,1,1,1, 1,1,1,1,
- 1,1,1,1, 1,1,1,1, 1,1,1,0, 0,0,0,0,
- 0,1,1,1, 1,1,1,1, 1,1,1,1, 1,1,1,1,
- 1,1,1,1, 1,1,1,1, 1,1,1,0, 0,0,0,0,
- );
-
- $u7len = strlen($str);
- $str = strval($str);
- $res = '';
-
- for ($i=0; $u7len > 0; $i++, $u7len--) {
- $u7 = $str[$i];
- if ($u7 == '+') {
- $i++;
- $u7len--;
- $ch = '';
-
- for (; $u7len > 0; $i++, $u7len--) {
- $u7 = $str[$i];
-
- if (!$Index_64[ord($u7)]) {
- break;
- }
-
- $ch .= $u7;
- }
-
- if ($ch == '') {
- if ($u7 == '-') {
- $res .= '+';
- }
-
- continue;
- }
-
- $res .= self::utf16_to_utf8(base64_decode($ch));
- }
- else {
- $res .= $u7;
- }
- }
-
- return $res;
- }
-
-
- /**
- * Converts string from UTF-16 to UTF-8 (helper for utf-7 to utf-8 conversion)
- *
- * @param string Input string
- *
- * @return string The converted string
- */
- public static function utf16_to_utf8($str)
- {
- $len = strlen($str);
- $dec = '';
-
- for ($i = 0; $i < $len; $i += 2) {
- $c = ord($str[$i]) << 8 | ord($str[$i + 1]);
- if ($c >= 0x0001 && $c <= 0x007F) {
- $dec .= chr($c);
- }
- else if ($c > 0x07FF) {
- $dec .= chr(0xE0 | (($c >> 12) & 0x0F));
- $dec .= chr(0x80 | (($c >> 6) & 0x3F));
- $dec .= chr(0x80 | (($c >> 0) & 0x3F));
- }
- else {
- $dec .= chr(0xC0 | (($c >> 6) & 0x1F));
- $dec .= chr(0x80 | (($c >> 0) & 0x3F));
- }
- }
-
- return $dec;
- }
-
-
- /**
- * Convert the data ($str) from RFC 2060's UTF-7 to UTF-8.
- * If input data is invalid, return the original input string.
- * RFC 2060 obviously intends the encoding to be unique (see
- * point 5 in section 5.1.3), so we reject any non-canonical
- * form, such as &ACY- (instead of &-) or &AMA-&AMA- (instead
- * of &AMAAwA-).
- *
- * Translated from C to PHP by Thomas Bruederli <roundcube@gmail.com>
- *
- * @param string $str Input string (UTF7-IMAP)
- *
- * @return string Output string (UTF-8)
- */
- public static function utf7imap_to_utf8($str)
- {
- $Index_64 = array(
- -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
- -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,-1,
- -1,-1,-1,-1, -1,-1,-1,-1, -1,-1,-1,62, 63,-1,-1,-1,
- 52,53,54,55, 56,57,58,59, 60,61,-1,-1, -1,-1,-1,-1,
- -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10, 11,12,13,14,
- 15,16,17,18, 19,20,21,22, 23,24,25,-1, -1,-1,-1,-1,
- -1,26,27,28, 29,30,31,32, 33,34,35,36, 37,38,39,40,
- 41,42,43,44, 45,46,47,48, 49,50,51,-1, -1,-1,-1,-1
- );
-
- $u7len = strlen($str);
- $str = strval($str);
- $p = '';
- $err = '';
-
- for ($i=0; $u7len > 0; $i++, $u7len--) {
- $u7 = $str[$i];
- if ($u7 == '&') {
- $i++;
- $u7len--;
- $u7 = $str[$i];
-
- if ($u7len && $u7 == '-') {
- $p .= '&';
- continue;
- }
-
- $ch = 0;
- $k = 10;
- for (; $u7len > 0; $i++, $u7len--) {
- $u7 = $str[$i];
-
- if ((ord($u7) & 0x80) || ($b = $Index_64[ord($u7)]) == -1) {
- break;
- }
-
- if ($k > 0) {
- $ch |= $b << $k;
- $k -= 6;
- }
- else {
- $ch |= $b >> (-$k);
- if ($ch < 0x80) {
- // Printable US-ASCII
- if (0x20 <= $ch && $ch < 0x7f) {
- return $err;
- }
- $p .= chr($ch);
- }
- else if ($ch < 0x800) {
- $p .= chr(0xc0 | ($ch >> 6));
- $p .= chr(0x80 | ($ch & 0x3f));
- }
- else {
- $p .= chr(0xe0 | ($ch >> 12));
- $p .= chr(0x80 | (($ch >> 6) & 0x3f));
- $p .= chr(0x80 | ($ch & 0x3f));
- }
-
- $ch = ($b << (16 + $k)) & 0xffff;
- $k += 10;
- }
- }
-
- // Non-zero or too many extra bits
- if ($ch || $k < 6) {
- return $err;
- }
-
- // BASE64 not properly terminated
- if (!$u7len || $u7 != '-') {
- return $err;
- }
-
- // Adjacent BASE64 sections
- if ($u7len > 2 && $str[$i+1] == '&' && $str[$i+2] != '-') {
- return $err;
- }
- }
- // Not printable US-ASCII
- else if (ord($u7) < 0x20 || ord($u7) >= 0x7f) {
- return $err;
- }
- else {
- $p .= $u7;
- }
- }
-
- return $p;
- }
-
-
- /**
- * Convert the data ($str) from UTF-8 to RFC 2060's UTF-7.
- * Unicode characters above U+FFFF are replaced by U+FFFE.
- * If input data is invalid, return an empty string.
- *
- * Translated from C to PHP by Thomas Bruederli <roundcube@gmail.com>
- *
- * @param string $str Input string (UTF-8)
- *
- * @return string Output string (UTF7-IMAP)
- */
- public static function utf8_to_utf7imap($str)
- {
- $B64Chars = array(
- 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O',
- 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd',
- 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's',
- 't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7',
- '8', '9', '+', ','
- );
-
- $u8len = strlen($str);
- $base64 = 0;
- $i = 0;
- $p = '';
- $err = '';
-
- while ($u8len) {
- $u8 = $str[$i];
- $c = ord($u8);
-
- if ($c < 0x80) {
- $ch = $c;
- $n = 0;
- }
- else if ($c < 0xc2) {
- return $err;
- }
- else if ($c < 0xe0) {
- $ch = $c & 0x1f;
- $n = 1;
- }
- else if ($c < 0xf0) {
- $ch = $c & 0x0f;
- $n = 2;
- }
- else if ($c < 0xf8) {
- $ch = $c & 0x07;
- $n = 3;
- }
- else if ($c < 0xfc) {
- $ch = $c & 0x03;
- $n = 4;
- }
- else if ($c < 0xfe) {
- $ch = $c & 0x01;
- $n = 5;
- }
- else {
- return $err;
- }
-
- $i++;
- $u8len--;
-
- if ($n > $u8len) {
- return $err;
- }
-
- for ($j=0; $j < $n; $j++) {
- $o = ord($str[$i+$j]);
- if (($o & 0xc0) != 0x80) {
- return $err;
- }
- $ch = ($ch << 6) | ($o & 0x3f);
- }
-
- if ($n > 1 && !($ch >> ($n * 5 + 1))) {
- return $err;
- }
-
- $i += $n;
- $u8len -= $n;
-
- if ($ch < 0x20 || $ch >= 0x7f) {
- if (!$base64) {
- $p .= '&';
- $base64 = 1;
- $b = 0;
- $k = 10;
- }
- if ($ch & ~0xffff) {
- $ch = 0xfffe;
- }
-
- $p .= $B64Chars[($b | $ch >> $k)];
- $k -= 6;
- for (; $k >= 0; $k -= 6) {
- $p .= $B64Chars[(($ch >> $k) & 0x3f)];
- }
-
- $b = ($ch << (-$k)) & 0x3f;
- $k += 16;
- }
- else {
- if ($base64) {
- if ($k > 10) {
- $p .= $B64Chars[$b];
- }
- $p .= '-';
- $base64 = 0;
- }
-
- $p .= chr($ch);
- if (chr($ch) == '&') {
- $p .= '-';
- }
- }
- }
-
- if ($base64) {
- if ($k > 10) {
- $p .= $B64Chars[$b];
- }
- $p .= '-';
- }
-
- return $p;
- }
-
-
- /**
- * A method to guess character set of a string.
- *
- * @param string $string String.
- * @param string $failover Default result for failover.
- *
- * @return string Charset name
- */
- public static function detect($string, $failover='')
- {
- if (substr($string, 0, 4) == "\0\0\xFE\xFF") return 'UTF-32BE'; // Big Endian
- if (substr($string, 0, 4) == "\xFF\xFE\0\0") return 'UTF-32LE'; // Little Endian
- if (substr($string, 0, 2) == "\xFE\xFF") return 'UTF-16BE'; // Big Endian
- if (substr($string, 0, 2) == "\xFF\xFE") return 'UTF-16LE'; // Little Endian
- if (substr($string, 0, 3) == "\xEF\xBB\xBF") return 'UTF-8';
-
- // heuristics
- if ($string[0] == "\0" && $string[1] == "\0" && $string[2] == "\0" && $string[3] != "\0") return 'UTF-32BE';
- if ($string[0] != "\0" && $string[1] == "\0" && $string[2] == "\0" && $string[3] == "\0") return 'UTF-32LE';
- if ($string[0] == "\0" && $string[1] != "\0" && $string[2] == "\0" && $string[3] != "\0") return 'UTF-16BE';
- if ($string[0] != "\0" && $string[1] == "\0" && $string[2] != "\0" && $string[3] == "\0") return 'UTF-16LE';
-
- if (function_exists('mb_detect_encoding')) {
- // FIXME: the order is important, because sometimes
- // iso string is detected as euc-jp and etc.
- $enc = array(
- 'UTF-8', 'SJIS', 'GB2312',
- 'ISO-8859-1', 'ISO-8859-2', 'ISO-8859-3', 'ISO-8859-4',
- 'ISO-8859-5', 'ISO-8859-6', 'ISO-8859-7', 'ISO-8859-8', 'ISO-8859-9',
- 'ISO-8859-10', 'ISO-8859-13', 'ISO-8859-14', 'ISO-8859-15', 'ISO-8859-16',
- 'WINDOWS-1252', 'WINDOWS-1251', 'EUC-JP', 'EUC-TW', 'KOI8-R', 'BIG5',
- 'ISO-2022-KR', 'ISO-2022-JP',
- );
-
- $result = mb_detect_encoding($string, join(',', $enc));
- }
- else {
- // No match, check for UTF-8
- // from http://w3.org/International/questions/qa-forms-utf-8.html
- if (preg_match('/\A(
- [\x09\x0A\x0D\x20-\x7E]
- | [\xC2-\xDF][\x80-\xBF]
- | \xE0[\xA0-\xBF][\x80-\xBF]
- | [\xE1-\xEC\xEE\xEF][\x80-\xBF]{2}
- | \xED[\x80-\x9F][\x80-\xBF]
- | \xF0[\x90-\xBF][\x80-\xBF]{2}
- | [\xF1-\xF3][\x80-\xBF]{3}
- | \xF4[\x80-\x8F][\x80-\xBF]{2}
- )*\z/xs', substr($string, 0, 2048))
- ) {
- return 'UTF-8';
- }
- }
-
- return $result ? $result : $failover;
- }
-
-
- /**
- * Removes non-unicode characters from input.
- *
- * @param mixed $input String or array.
- *
- * @return mixed String or array
- */
- public static function clean($input)
- {
- // handle input of type array
- if (is_array($input)) {
- foreach ($input as $idx => $val) {
- $input[$idx] = self::clean($val);
- }
- return $input;
- }
-
- if (!is_string($input) || $input == '') {
- return $input;
- }
-
- // iconv/mbstring are much faster (especially with long strings)
- if (function_exists('mb_convert_encoding')) {
- if (($res = mb_convert_encoding($input, 'UTF-8', 'UTF-8')) !== false) {
- return $res;
- }
- }
-
- if (function_exists('iconv')) {
- if (($res = @iconv('UTF-8', 'UTF-8//IGNORE', $input)) !== false) {
- return $res;
- }
- }
-
- $seq = '';
- $out = '';
- $regexp = '/^('.
-// '[\x00-\x7F]'. // UTF8-1
- '|[\xC2-\xDF][\x80-\xBF]'. // UTF8-2
- '|\xE0[\xA0-\xBF][\x80-\xBF]'. // UTF8-3
- '|[\xE1-\xEC][\x80-\xBF][\x80-\xBF]'. // UTF8-3
- '|\xED[\x80-\x9F][\x80-\xBF]'. // UTF8-3
- '|[\xEE-\xEF][\x80-\xBF][\x80-\xBF]'. // UTF8-3
- '|\xF0[\x90-\xBF][\x80-\xBF][\x80-\xBF]'. // UTF8-4
- '|[\xF1-\xF3][\x80-\xBF][\x80-\xBF][\x80-\xBF]'.// UTF8-4
- '|\xF4[\x80-\x8F][\x80-\xBF][\x80-\xBF]'. // UTF8-4
- ')$/';
-
- for ($i = 0, $len = strlen($input); $i < $len; $i++) {
- $chr = $input[$i];
- $ord = ord($chr);
-
- // 1-byte character
- if ($ord <= 0x7F) {
- if ($seq) {
- $out .= preg_match($regexp, $seq) ? $seq : '';
- }
- $seq = '';
- $out .= $chr;
- // first (or second) byte of multibyte sequence
- }
- else if ($ord >= 0xC0) {
- if (strlen($seq) > 1) {
- $out .= preg_match($regexp, $seq) ? $seq : '';
- $seq = '';
- }
- else if ($seq && ord($seq) < 0xC0) {
- $seq = '';
- }
- $seq .= $chr;
- // next byte of multibyte sequence
- }
- else if ($seq) {
- $seq .= $chr;
- }
- }
-
- if ($seq) {
- $out .= preg_match($regexp, $seq) ? $seq : '';
- }
-
- return $out;
- }
-
-}