utfsafestring.php

См. документацию.

<?php
namespace Bitrix\Main\Text;
 
class UtfSafeString
{
    public static function getLastPosition($haystack, $needle)
    {
        if (mb_check_encoding((string)$haystack))
        {
            return mb_strrpos((string)$haystack, $needle);
        }
        return false;
    }
 
    public static function rtrimInvalidUtf($string)
    {
        //valid UTF-8 octet sequences
        //0xxxxxxx
        //110xxxxx 10xxxxxx
        //1110xxxx 10xxxxxx 10xxxxxx
        //11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
 
        $last4bytes = substr($string, -3);
        $reversed = array_reverse(unpack("C*", $last4bytes));
        if (($reversed[0] & 0x80) === 0x00) //ASCII
            return $string;
        elseif (($reversed[0] & 0xC0) === 0xC0) //Start of utf seq (cut it!)
            return substr($string, 0, -1);
        elseif (($reversed[1] & 0xE0) === 0xE0) //Start of utf seq (longer than 2 bytes)
            return substr($string, 0, -2);
        elseif (($reversed[2] & 0xE0) === 0xF0) //Start of utf seq (longer than 3 bytes)
            return substr($string, 0, -3);
        return $string;
    }

    public static function escapeInvalidUtf($string)
    {
        $escape = function($matches)
        {
            return (isset($matches[2])? '?' : $matches[1]);
        };
 
        return preg_replace_callback('/([\x00-\x7F]+
            |[\xC2-\xDF][\x80-\xBF]
            |\xE0[\xA0-\xBF][\x80-\xBF]|[\xE1-\xEC\xEE\xEF][\x80-\xBF]{2}|\xED[\x80-\x9F][\x80-\xBF])
            |([\x80-\xFF])/x', $escape, $string
        );
    }
 

    public static function pad($string, $padLen, $padStr = ' ', $padType = STR_PAD_RIGHT)
    {
        $strLength = mb_strlen($string);
        $padStrLength = mb_strlen($padStr);
        if (!$strLength && ($padType == STR_PAD_RIGHT || $padType == STR_PAD_LEFT))
        {
            $strLength = 1; // @debug
        }
        if (!$padLen || !$padStrLength || $padLen <= $strLength)
        {
            return $string;
        }
 
        $result = null;
        $repeat = ceil(($padLen - $strLength) / $padStrLength);
        if ($padType == STR_PAD_RIGHT)
        {
            $result = $string . str_repeat($padStr, $repeat);
            $result = mb_substr($result, 0, $padLen);
        }
        else if ($padType == STR_PAD_LEFT)
        {
            $result = str_repeat($padStr, $repeat) . $string;
            $result = mb_substr($result, -$padLen);
        }
        else if ($padType == STR_PAD_BOTH)
        {
            $length = ($padLen - $strLength) / 2;
            $repeat = ceil($length / $padStrLength);
            $result = mb_substr(str_repeat($padStr, $repeat), 0, floor($length))
                .$string
                .mb_substr(str_repeat($padStr, $repeat), 0, ceil($length));
        }
 
        return $result;
    }

    public static function checkEncoding($data)
    {
        if (!is_string($data) && !is_array($data))
        {
            return true;
        }
 
        return mb_check_encoding($data);
    }
}