Shim for servers that do not support mb_string functions. modified from Patchwork. Usage: if(!function_exists('mb_strtolower')) { require_once('mb_string_shim.php'); }

mb_string_shim.php

<?php
/*
 * Copyright (C) 2013 Nicolas Grekas - p@tchwork.com
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the (at your option):
 * Apache License v2.0 (http://apache.org/licenses/LICENSE-2.0.txt), or
 * GNU General Public License v2.0 (http://gnu.org/licenses/gpl-2.0.txt).
 */

/**
 * Partial mbstring implementation in PHP, iconv based, UTF-8 centric.
 *
 * Implemented:
 * - mb_convert_encoding	 - Convert character encoding
 * - mb_decode_mimeheader	- Decode string in MIME header field
 * - mb_encode_mimeheader	- Encode string for MIME header XXX NATIVE IMPLEMENTATION IS REALLY BUGGED
 * - mb_convert_case		 - Perform case folding on a string
 * - mb_internal_encoding	- Set/Get internal character encoding
 * - mb_list_encodings	   - Returns an array of all supported encodings
 * - mb_strlen			   - Get string length
 * - mb_strpos			   - Find position of first occurrence of string in a string
 * - mb_strrpos			  - Find position of last occurrence of a string in a string
 * - mb_strtolower		   - Make a string lowercase
 * - mb_strtoupper		   - Make a string uppercase
 * - mb_substitute_character - Set/Get substitution character
 * - mb_substr			   - Get part of string
 * - mb_stripos			  - Finds position of first occurrence of a string within another, case insensitive
 * - mb_stristr			  - Finds first occurrence of a string within another, case insensitive
 * - mb_strrchr			  - Finds the last occurrence of a character in a string within another
 * - mb_strrichr			 - Finds the last occurrence of a character in a string within another, case insensitive
 * - mb_strripos			 - Finds position of last occurrence of a string within another, case insensitive
 * - mb_strstr			   - Finds first occurrence of a string within anothers
 *
 * Not implemented:
 * - mb_convert_kana			   - Convert "kana" one from another ("zen-kaku", "han-kaku" and more)
 * - mb_convert_variables		  - Convert character code in variable(s)
 * - mb_decode_numericentity	   - Decode HTML numeric string reference to character
 * - mb_encode_numericentity	   - Encode character to HTML numeric string reference
 * - mb_ereg*					  - Regular expression with multibyte support
 * - mb_get_info				   - Get internal settings of mbstring
 * - mb_http_input				 - Detect HTTP input character encoding
 * - mb_http_output				- Set/Get HTTP output character encoding
 * - mb_list_mime_names			- Returns an array or string of all supported mime names
 * - mb_output_handler			 - Callback function converts character encoding in output buffer
 * - mb_parse_str				  - Parse GET/POST/COOKIE data and set global variable
 * - mb_preferred_mime_name		- Get MIME charset string
 * - mb_regex_encoding			 - Returns current encoding for multibyte regex as string
 * - mb_regex_set_options		  - Set/Get the default options for mbregex functions
 * - mb_send_mail				  - Send encoded mail
 * - mb_split					  - Split multibyte string using regular expression
 * - mb_strcut					 - Get part of string
 * - mb_strimwidth				 - Get truncated string with specified width
 * - mb_strwidth				   - Return width of string
 * - mb_substr_count			   - Count the number of substring occurrences
 */
if( !class_exists('PatchworkMbstring') ) {
  class PatchworkMbstring
  {
  	const MB_CASE_FOLD = PHP_INT_MAX;
  
  	protected static
  
  	$encoding_list = array('ASCII', 'UTF-8'),
  	$language = 'neutral',
  	$internal_encoding = 'UTF-8',
  	$caseFold = array(
  		array('µ','?',"\xCD\x85",'?',"\xCF\x90","\xCF\x91","\xCF\x95","\xCF\x96","\xCF\xB0","\xCF\xB1","\xCF\xB5","\xE1\xBA\x9B","\xE1\xBE\xBE"),
  		array('µ','s','?',	   's','ß',	   '?',	   'f',	   'p',	   '?',	   '?',	   'e',	   "\xE1\xB9\xA1",'?'		   )
  	);
  
  
  	static function mb_convert_encoding($s, $to_encoding, $from_encoding = INF)
  	{
  		INF === $from_encoding && $from_encoding = self::$internal_encoding;
  
  		$from_encoding = strtolower($from_encoding);
  		$to_encoding = strtolower($to_encoding);
  
  		if ('base64' === $from_encoding)
  		{
  			$s = base64_decode($s);
  			$from_encoding = $to_encoding;
  		}
  
  		if ('base64' === $to_encoding) return base64_encode($s);
  
  		if ('html-entities' === $to_encoding)
  		{
  			'html-entities' === $from_encoding && $from_encoding = 'Windows-1252';
  			'utf-8' === $from_encoding
  				|| 'utf8' === $from_encoding
  				|| $s = iconv($from_encoding, 'UTF-8//IGNORE', $s);
  			return preg_replace_callback('/[\x80-\xFF]+/', array(__CLASS__, 'html_encoding_callback'), $s);
  		}
  
  		if ('html-entities' === $from_encoding)
  		{
  			$s = html_entity_decode($s, ENT_COMPAT, 'UTF-8');
  			$from_encoding = 'UTF-8';
  		}
  
  		return iconv($from_encoding, $to_encoding . '//IGNORE', $s);
  	}
  
  	static function mb_decode_mimeheader($s)
  	{
  		return iconv_mime_decode($s, 2, self::$internal_encoding . '//IGNORE');
  	}
  
  	static function mb_encode_mimeheader($s, $charset = INF, $transfer_encoding = INF, $linefeed = INF, $indent = INF)
  	{
  		user_error('mb_encode_mimeheader() is bugged. Please use iconv_mime_encode() instead', E_USER_WARNING);
  	}
  
  
  	static function mb_convert_case($s, $mode, $encoding = INF)
  	{
  		if ('' === $s .= '') return '';
  
  		if (INF === $encoding) $encoding = self::$internal_encoding;
  		else $encoding = strtoupper($encoding);
  
  		if ('UTF-8' === $encoding || 'UTF8' === $encoding) $encoding = INF;
  		else $s = iconv($encoding, 'UTF-8//IGNORE', $s);
  
  		if (MB_CASE_TITLE == $mode)
  		{
  			$s = preg_replace_callback('/\b\p{Ll}/u', array(__CLASS__, 'title_case_upper'), $s);
  			$s = preg_replace_callback('/\B[\p{Lu}\p{Lt}]+/u', array(__CLASS__, 'title_case_lower'), $s);
  		}
  		else
  		{
  			if (MB_CASE_UPPER == $mode)
  			{
  				static $upper;
  				isset($upper) || $upper = static::getData('upperCase');
  				$map = $upper;
  			}
  			else
  			{
  				if (self::MB_CASE_FOLD === $mode) $s = str_replace(self::$caseFold[0], self::$caseFold[1], $s);
  
  				static $lower;
  				isset($lower) || $lower = static::getData('lowerCase');
  				$map = $lower;
  			}
  
  			static $ulen_mask = array("\xC0" => 2, "\xD0" => 2, "\xE0" => 3, "\xF0" => 4);
  
  			$i = 0;
  			$len = strlen($s);
  
  			while ($i < $len)
  			{
  				$ulen = $s[$i] < "\x80" ? 1 : $ulen_mask[$s[$i] & "\xF0"];
  				$uchr = substr($s, $i, $ulen);
  				$i += $ulen;
  
  				if (isset($map[$uchr]))
  				{
  					$uchr = $map[$uchr];
  					$nlen = strlen($uchr);
  
  					if ($nlen == $ulen)
  					{
  						$nlen = $i;
  						do $s[--$nlen] = $uchr[--$ulen];
  						while ($ulen);
  					}
  					else
  					{
  						$s = substr_replace($s, $uchr, $i - $ulen, $ulen);
  						$len += $nlen - $ulen;
  						$i   += $nlen - $ulen;
  					}
  				}
  			}
  		}
  
  		if (INF === $encoding) return $s;
  		else return iconv('UTF-8', $encoding, $s);
  	}
  
  	static function mb_internal_encoding($encoding = INF)
  	{
  		if (INF === $encoding) return self::$internal_encoding;
  		else $encoding = strtoupper($encoding);
  
  		if ('UTF-8' === $encoding || 'UTF8' === $encoding || false !== @iconv($encoding, $encoding, ' '))
  		{
  			self::$internal_encoding = 'UTF8' === $encoding ? 'UTF-8' : $encoding;
  
  			return true;
  		}
  
  		return false;
  	}
  
  	static function mb_language($lang = INF)
  	{
  		if (INF === $lang) return self::$language;
  
  		switch ($lang = strtolower($lang))
  		{
  		case 'uni':
  		case 'neutral':
  			self::$language = $lang;
  			return true;
  		}
  
  		return false;
  	}
  
  	static function mb_list_encodings()
  	{
  		return array('UTF-8');
  	}
  
  	static function mb_encoding_aliases($encoding)
  	{
  		switch (strtolower($encoding))
  		{
  		case 'utf8':
  		case 'utf-8': return array('utf8');
  		}
  
  		return false;
  	}
  
  	static function mb_check_encoding($var = INF, $encoding = INF)
  	{
  		if (INF === $encoding)
  		{
  			if (INF === $var) return false;
  			$encoding = self::$internal_encoding;
  		}
  
  		return false !== mb_detect_encoding($var, array($encoding), true);
  	}
  
  	static function mb_detect_encoding($str, $encoding_list = INF, $strict = false)
  	{
  		if (INF === $encoding_list) $encoding_list = self::$encoding_list;
  		else
  		{
  			if (! is_array($encoding_list)) $encoding_list = array_map('trim', explode(',', $encoding_list));
  			$encoding_list = array_map('strtoupper', $encoding_list);
  		}
  
  		foreach ($encoding_list as $enc)
  		{
  			switch ($enc)
  			{
  			case 'ASCII':
  				if (! preg_match('/[\x80-\xFF]/', $str)) return $enc;
  				break;
  
  			case 'UTF8':
  			case 'UTF-8':
  				if (preg_match('//u', $str)) return $enc;
  				break;
  
  			default:
  				return strncmp($enc, 'ISO-8859-', 9) ? false : $enc;
  			}
  		}
  
  		return false;
  	}
  
  	static function mb_detect_order($encoding_list = INF)
  	{
  		if (INF === $encoding_list) return self::$encoding_list;
  
  		if (! is_array($encoding_list)) $encoding_list = array_map('trim', explode(',', $encoding_list));
  		$encoding_list = array_map('strtoupper', $encoding_list);
  
  		foreach ($encoding_list as $enc)
  		{
  			switch ($enc)
  			{
  			default: if (strncmp($enc, 'ISO-8859-', 9)) return false;
  			case 'ASCII':
  			case 'UTF8':
  			case 'UTF-8':
  			}
  		}
  
  		self::$encoding_list = $encoding_list;
  
  		return true;
  	}
  
  	static function mb_strlen($s, $encoding = INF)
  	{
  		INF === $encoding && $encoding = self::$internal_encoding;
  		return iconv_strlen($s, $encoding . '//IGNORE');
  	}
  
  	static function mb_strpos ($haystack, $needle, $offset = 0, $encoding = INF)
  	{
  		INF === $encoding && $encoding = self::$internal_encoding;
  		if ('' === $needle .= '')
  		{
  			user_error(__METHOD__ . ': Empty delimiter', E_USER_WARNING);
  			return false;
  		}
  		else return iconv_strpos($haystack, $needle, $offset, $encoding . '//IGNORE');
  	}
  
  	static function mb_strrpos($haystack, $needle, $offset = 0, $encoding = INF)
  	{
  		INF === $encoding && $encoding = self::$internal_encoding;
  
  		if ($offset != (int) $offset)
  		{
  			$offset = 0;
  		}
  		else if ($offset = (int) $offset)
  		{
  			$haystack = self::mb_substr($haystack, $offset, 2147483647, $encoding);
  		}
  
  		$pos = iconv_strrpos($haystack, $needle, $encoding . '//IGNORE');
  
  		return false !== $pos ? $offset + $pos : false;
  	}
  
  	static function mb_strtolower($s, $encoding = INF)
  	{
  		return self::mb_convert_case($s, MB_CASE_LOWER, $encoding);
  	}
  
  	static function mb_strtoupper($s, $encoding = INF)
  	{
  		return self::mb_convert_case($s, MB_CASE_UPPER, $encoding);
  	}
  
  	static function mb_substitute_character($c = INF)
  	{
  		return INF !== $c ? false : 'none';
  	}
  
  	static function mb_substr($s, $start, $length = null, $encoding = INF)
  	{
  		INF === $encoding && $encoding = self::$internal_encoding;
  
  		if ($start < 0)
  		{
  			$start = iconv_strlen($s, $encoding . '//IGNORE') + $start;
  			if ($start < 0) $start = 0;
  		}
  
  		if (null === $length) $length = 2147483647;
  		else if ($length < 0)
  		{
  			$length = iconv_strlen($s, $encoding . '//IGNORE') + $length - $start;
  			if ($length < 0) return '';
  		}
  
  		return iconv_substr($s, $start, $length, $encoding . '//IGNORE') . '';
  	}
  
  	static function mb_stripos($haystack, $needle, $offset = 0, $encoding = INF)
  	{
  		INF === $encoding && $encoding = self::$internal_encoding;
  		$haystack = self::mb_convert_case($haystack, self::MB_CASE_FOLD, $encoding);
  		$needle = self::mb_convert_case($needle, self::MB_CASE_FOLD, $encoding);
  		return self::mb_strpos($haystack, $needle, $offset, $encoding);
  	}
  
  	static function mb_stristr($haystack, $needle, $part = false, $encoding = INF)
  	{
  		$pos = self::mb_stripos($haystack, $needle, 0, $encoding);
  		return self::getSubpart($pos, $part, $haystack, $encoding);
  	}
  
  	static function mb_strrchr($haystack, $needle, $part = false, $encoding = INF)
  	{
  		INF === $encoding && $encoding = self::$internal_encoding;
  		$needle = self::mb_substr($needle, 0, 1, $encoding);
  		$pos = iconv_strrpos($haystack, $needle, $encoding);
  		return self::getSubpart($pos, $part, $haystack, $encoding);
  	}
  
  	static function mb_strrichr($haystack, $needle, $part = false, $encoding = INF)
  	{
  		$needle = self::mb_substr($needle, 0, 1, $encoding);
  		$pos = self::mb_strripos($haystack, $needle, $encoding);
  		return self::getSubpart($pos, $part, $haystack, $encoding);
  	}
  
  	static function mb_strripos($haystack, $needle, $offset = 0, $encoding = INF)
  	{
  		INF === $encoding && $encoding = self::$internal_encoding;
  		$haystack = self::mb_convert_case($haystack, self::MB_CASE_FOLD, $encoding);
  		$needle = self::mb_convert_case($needle, self::MB_CASE_FOLD, $encoding);
  		return self::mb_strrpos($haystack, $needle, $offset, $encoding);
  	}
  
  	static function mb_strstr($haystack, $needle, $part = false, $encoding = INF)
  	{
  		$pos = strpos($haystack, $needle);
  		if (false === $pos) return false;
  		if ($part) return substr($haystack, 0, $pos);
  		else return substr($haystack, $pos);
  	}
  
  
  	protected static function getSubpart($pos, $part, $haystack, $encoding)
  	{
  		INF === $encoding && $encoding = self::$internal_encoding;
  
  		if (false === $pos) return false;
  		if ($part) return self::mb_substr($haystack, 0, $pos, $encoding);
  		else return self::mb_substr($haystack, $pos, null, $encoding);
  	}
  
  	protected static function html_encoding_callback($m)
  	{
  		return htmlentities($m[0], ENT_COMPAT, 'UTF-8');
  	}
  
  	protected static function title_case_lower($s)
  	{
  		return self::mb_convert_case($s[0], MB_CASE_LOWER, 'UTF-8');
  	}
  
  	protected static function title_case_upper($s)
  	{
  		return self::mb_convert_case($s[0], MB_CASE_UPPER, 'UTF-8');
  	}
  
  	protected static function getData($file)
  	{
  		$file = __DIR__ . '/unidata/' . $file . '.ser';
  		if (file_exists($file)) return unserialize(file_get_contents($file));
  		else return false;
  	}
  }
}


const MB_OVERLOAD_MAIL = 1;
const MB_OVERLOAD_STRING = 2;
const MB_OVERLOAD_REGEX = 4;
const MB_CASE_UPPER = 0;
const MB_CASE_LOWER = 1;
const MB_CASE_TITLE = 2;
if(!function_exists('mb_convert_encoding')) {
	function mb_convert_encoding($s, $to, $from = INF) {return PatchworkMbstring::mb_convert_encoding($s, $to, $from);};
}
if(!function_exists('mb_decode_mimeheader')) {
	function mb_decode_mimeheader($s) {return PatchworkMbstring::mb_decode_mimeheader($s);};
}
if(!function_exists('mb_encode_mimeheader')) {
	function mb_encode_mimeheader($s, $charset = INF, $transfer_enc = INF, $lf = INF, $indent = INF) {return PatchworkMbstring::mb_encode_mimeheader($s, $charset, $transfer_enc, $lf, $indent);};
}
if(!function_exists('mb_convert_case')) {
	function mb_convert_case($s, $mode, $enc = INF) {return PatchworkMbstring::mb_convert_case($s, $mode, $enc);};
}
if(!function_exists('mb_internal_encoding')) {
	function mb_internal_encoding($enc = INF) {return PatchworkMbstring::mb_internal_encoding($enc);};
}
if(!function_exists('mb_language')) {
	function mb_language($lang = INF) {return PatchworkMbstring::mb_language($lang);}
}
if(!function_exists('mb_list_encodings')) {
	function mb_list_encodings() {return PatchworkMbstring::mb_list_encodings();};
}
if(!function_exists('mb_encoding_aliases')) {
	function mb_encoding_aliases($encoding) {return PatchworkMbstring::mb_encoding_aliases($encoding);}
}
if(!function_exists('mb_check_encoding')) {
	function mb_check_encoding($var = INF, $encoding = INF) {return PatchworkMbstring::mb_check_encoding($var, $encoding);}
}
if(!function_exists('mb_detect_encoding')) {
	function mb_detect_encoding($str, $encoding_list = INF, $strict = false) {return PatchworkMbstring::mb_detect_encoding($str, $encoding_list, $strict);}
}
if(!function_exists('mb_detect_order')) {
	function mb_detect_order($encoding_list = INF) {return PatchworkMbstring::mb_detect_order($encoding_list);}
}
if(!function_exists('mb_parse_str')) {
	function mb_parse_str($s, &$result = array()) {return parse_str($s, $result);};
}
if(!function_exists('mb_strlen')) {
	function mb_strlen($s, $enc = INF) {return PatchworkMbstring::mb_strlen($s, $enc);};
}
if(!function_exists('mb_strpos')) {
	function mb_strpos($s, $needle, $offset = 0, $enc = INF) {return PatchworkMbstring::mb_strpos($s, $needle, $offset, $enc);};
}
if(!function_exists('mb_strtolower')) {
	function mb_strtolower($s, $enc = INF) {return PatchworkMbstring::mb_strtolower($s, $enc);};
}
if(!function_exists('mb_strtoupper')) {
	function mb_strtoupper($s, $enc = INF) {return PatchworkMbstring::mb_strtoupper($s, $enc);};
}
if(!function_exists('mb_substitute_character')) {
	function mb_substitute_character($char = INF) {return PatchworkMbstring::mb_substitute_character($char);};
}
if(!function_exists('mb_substr_count')) {
	function mb_substr_count($s, $needle) {return substr_count($s, $needle);};
}
if(!function_exists('mb_substr')) {
	function mb_substr($s, $start, $length = 2147483647, $enc = INF) {return PatchworkMbstring::mb_substr($s, $start, $length, $enc);};
}
if(!function_exists('mb_stripos')) {
	function mb_stripos($s, $needle, $offset = 0, $enc = INF) {return PatchworkMbstring::mb_stripos($s, $needle, $offset, $enc);};
}
if(!function_exists('mb_stristr')) {
	function mb_stristr($s, $needle, $part = false, $enc = INF) {return PatchworkMbstring::mb_stristr($s, $needle, $part, $enc);};
}
if(!function_exists('mb_strrchr')) {
	function mb_strrchr($s, $needle, $part = false, $enc = INF) {return PatchworkMbstring::mb_strrchr($s, $needle, $part, $enc);};
}
if(!function_exists('mb_strrichr')) {
	function mb_strrichr($s, $needle, $part = false, $enc = INF) {return PatchworkMbstring::mb_strrichr($s, $needle, $part, $enc);};
}
if(!function_exists('mb_strripos')) {
	function mb_strripos($s, $needle, $offset = 0, $enc = INF) {return PatchworkMbstring::mb_strripos($s, $needle, $offset, $enc);};
}
if(!function_exists('mb_strrpos')) {
	function mb_strrpos($s, $needle, $offset = 0, $enc = INF) {return PatchworkMbstring::mb_strrpos($s, $needle, $offset, $enc);};
}
if(!function_exists('mb_strstr')) {
	function mb_strstr($s, $needle, $part = false, $enc = INF) {return PatchworkMbstring::mb_strstr($s, $needle, $part, $enc);};
}