StringOperation.php

<?php
/*
 SPDX-FileCopyrightText: © 2015 Siemens AG
 
 SPDX-License-Identifier: GPL-2.0-only
*/
 
 
namespace Fossology\Lib\Util;
 
class StringOperation
{
  public static function getCommonHead($a, $b)
  {
    $headLength = 0;
    $maxNumberOfCharsToCompare = min(strlen($a), strlen($b));
    while ($headLength < $maxNumberOfCharsToCompare &&
      $a[$headLength] === $b[$headLength]) {
      $headLength += 1;
    }
    return substr($a,0,$headLength);
  }
 
  public static function replaceUnicodeControlChar($input, $replace="")
  {
    // 'Non-printable' is ASCII < 0x20 (excluding \r, \n and tab) and
    // 0x7F - 0x9F.
    return preg_replace('/[\x00-\x08\x0B\x0C\x0E-\x1F\x7F-\x9F]/u', $replace,
      $input);
  }
 
  public static function stringStartsWith($haystack, $needle)
  {
    return strncmp($haystack, $needle, strlen($needle)) === 0;
  }
}