php-utf8.php

<?php

/**
 * The dynamic loader for the PHP-UTF8 library.
 *
 * It checks whether you have the mbstring extension available and includes
 * relevant files on that basis, falling back to the native (as in written in
 * PHP) version if mbstring is unavailabe.
 *
 * It's probably easiest to use this, if you don't want to understand the
 * dependencies involved, in conjunction with PHP versions etc. At the same time,
 * you might get better performance by managing loading yourself. The smartest
 * way to do this, bearing in mind performance, is probably to "load on demand"
 * - i.e. just before you use these functions in your code, load the version you
 * need.
 *
 * It makes sure the the following functions are available;
 * utf8_strlen, utf8_strpos, utf8_strrpos, utf8_substr, utf8_strtolower, utf8_strtoupper
 *
 * Other functions in the ./native directory depend on these six functions being available
 *
 * @package php-utf8
 */

// Check whether PCRE has been compiled with UTF-8 support
$UTF8_ar = array();
if (preg_match('/^.{1}$/u', "ñ", $UTF8_ar) != 1)
	trigger_error('PCRE is not compiled with UTF-8 support', E_USER_ERROR);

unset($UTF8_ar);

/**
 * UTF8 constant, holds the current directory.
 */
if (!defined('UTF8'))
	define('UTF8', dirname(__FILE__));

/**
 * PHP_UTF8_MODE constant, will be 'native' or 'mbstring'.
 */
if (!defined('PHP_UTF8_MODE'))
{
	if (extension_loaded('mbstring'))
		define('PHP_UTF8_MODE', 'mbstring');
	else
		define('PHP_UTF8_MODE', 'native');
}

if (PHP_UTF8_MODE == 'mbstring')
{
	// If string overloading is active, it will break many of the native implementations
	if (ini_get('mbstring.func_overload') & MB_OVERLOAD_STRING)
		trigger_error('String functions are overloaded by mbstring, must be set to 0, 1 or 4 in php.ini for PHP-UTF8 to work.', E_USER_ERROR);

	// Also need to check we have the correct internal mbstring encoding
	mb_language('uni');
	mb_internal_encoding('UTF-8');

}
elseif (PHP_UTF8_MODE == 'native')
{
	if (!defined('UTF8_CORE'))
		require UTF8.'/utils/unicode.php';
}

if (!defined('UTF8_CORE'))
	require UTF8.'/core/'.PHP_UTF8_MODE.'.php';