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/* * boolean utf8_validate( string $s ) : * * Check that $s string is a valid UTF-8 string. * Return TRUE on success, FALSE on error. * It does NOT check for overlong UTF-8 sequences !  *  * Copyright 2007 (c) LiNuCe, GCoiNCoin Inc LTD Gmbh * Under GPL Licence v2 or later. */	function utf8_validate( $s )	{		$iLen = strlen( $s );		for( $i=0 ; $i<$iLen ; $i++ )		{			$iByte = ord( $s[$i] );			if( $iByte < 128 ) continue ;						if    ( ( $iByte & 0xC0 ) == 0xC0 ) $iCharLen = 2 ;			elseif( ( $iByte & 0xE0 ) == 0xE0 ) $iCharLen = 3 ;			elseif( ( $iByte & 0xF0 ) == 0xF0 ) $iCharLen = 4 ;			else return FALSE ;			$iCharLen -- ;			while( $iCharLen )			{					  if( ( ord($s[$i]) & 0x80 ) != 0x80 ) return FALSE ;					  $iCharLen -- ;					  $i++ ;			}		}		return TRUE ;	}