root/trunk/system/core/utf8.php

<?php defined('SYSPATH') or die('No direct script access.');
/**
 * A port of phputf8 to a unified file/class. Checks PHP status to ensure that
 * UTF-8 support is available and normalize global variables to UTF-8. It also
 * provides multi-byte aware replacement string functions.
 *
 * This file is licensed differently from the rest of Kohana. As a port of
 * phputf8, which is LGPL software, this file is released under the LGPL.
 *
 * PCRE needs to be compiled with UTF-8 support (--enable-utf8).
 * Support for Unicode properties is highly recommended (--enable-unicode-properties).
 * @see http://php.net/manual/reference.pcre.pattern.modifiers.php
 *
 * UTF-8 conversion will be much more reliable if the iconv extension is loaded.
 * @see http://php.net/iconv
 *
 * The mbstring extension is highly recommended, but must not be overloading
 * string functions.
 * @see http://php.net/mbstring
 *
 * $Id$
 *
 * @package    Core
 * @author     Kohana Team
 * @copyright  (c) 2007 Kohana Team
 * @copyright  (c) 2005 Harry Fuecks
 * @license    http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt
 */

if ( ! preg_match('/^.$/u', 'ñ'))
{
    trigger_error
    (
        '<a href="http://php.net/pcre">PCRE</a> has not been compiled with UTF-8 support. '.
        'See <a href="http://php.net/manual/reference.pcre.pattern.modifiers.php">PCRE Pattern Modifiers</a> '.
        'for more information. This application cannot be run without UTF-8 support.',
        E_USER_ERROR
    );
}

if ( ! extension_loaded('iconv'))
{
    trigger_error
    (
        'The <a href="http://php.net/iconv">iconv</a> extension is not loaded. '.
        'Without iconv, strings cannot be properly translated to UTF-8 from user input. '.
        'This application cannot be run without UTF-8 support.',
        E_USER_ERROR
    );
}

if (extension_loaded('mbstring') AND (ini_get('mbstring.func_overload') & MB_OVERLOAD_STRING))
{
    trigger_error
    (
        'The <a href="http://php.net/mbstring">mbstring</a> extension is overloading PHP\'s native string functions. '.
        'Disable this by setting mbstring.func_overload to 0, 1, 4 or 5 in php.ini or a .htaccess file.'.
        'This application cannot be run without UTF-8 support.',
        E_USER_ERROR
    );
}

// Check PCRE support for Unicode properties such as \p and \X.
$ER = error_reporting(0);
define('PCRE_UNICODE_PROPERTIES', (bool) preg_match('/^\pL$/u', 'ñ'));
error_reporting($ER);

// SERVER_UTF8 ? use mb_* functions : use non-native functions
if (extension_loaded('mbstring'))
{
    mb_internal_encoding('UTF-8');
    define('SERVER_UTF8', TRUE);
}
else
{
    define('SERVER_UTF8', FALSE);
}

// Convert all global variables to UTF-8.
$_GET    = utf8::clean($_GET);
$_POST   = utf8::clean($_POST);
$_COOKIE = utf8::clean($_COOKIE);
$_SERVER = utf8::clean($_SERVER);

if (PHP_SAPI == 'cli')
{
    // Convert command line arguments
    $_SERVER['argv'] = utf8::clean($_SERVER['argv']);
}

final class utf8 {

    // Called methods
    static $called = array();

    /**
     * Recursively cleans arrays, objects, and strings. Removes ASCII control
     * codes and converts to UTF-8 while silently discarding incompatible
     * UTF-8 characters.
     *
     * @param   string  string to clean
     * @return  string
     */
    public static function clean($str)
    {
        if (is_array($str) OR is_object($str))
        {
            foreach ($str as $key => $val)
            {
                // Recursion!
                $str[self::clean($key)] = self::clean($val);
            }
        }
        elseif (is_string($str) AND $str !== '')
        {
            // Remove control characters
            $str = self::strip_ascii_ctrl($str);

            if ( ! self::is_ascii($str))
            {
                // Disable notices
                $ER = error_reporting(~E_NOTICE);

                // iconv is expensive, so it is only used when needed
                $str = iconv('UTF-8', 'UTF-8//IGNORE', $str);

                // Turn notices back on
                error_reporting($ER);
            }
        }

        return $str;
    }

    /**
     * Tests whether a string contains only 7bit ASCII bytes. This is used to
     * determine when to use native functions or UTF-8 functions.
     *
     * @param   string  string to check
     * @return  bool
     */
    public static function is_ascii($str)
    {
        return ! preg_match('/[^\x00-\x7F]/S', $str);
    }

    /**
     * Strips out device control codes in the ASCII range.
     *
     * @param   string  string to clean
     * @return  string
     */
    public static function strip_ascii_ctrl($str)
    {
        return preg_replace('/[\x00-\x08\x0B\x0C\x0E-\x1F\x7F]+/S', '', $str);
    }

    /**
     * Strips out all non-7bit ASCII bytes.
     *
     * @param   string  string to clean
     * @return  string
     */
    public static function strip_non_ascii($str)
    {
        return preg_replace('/[^\x00-\x7F]+/S', '', $str);
    }

    /**
     * Replaces special/accented UTF-8 characters by ASCII-7 'equivalents'.
     *
     * @author  Andreas Gohr <andi@splitbrain.org>
     *
     * @param   string   string to transliterate
     * @param   integer  -1 lowercase only, +1 uppercase only, 0 both cases
     * @return  string
     */
    public static function transliterate_to_ascii($str, $case = 0)
    {
        if ( ! isset(self::$called[__FUNCTION__]))
        {
            require SYSPATH.'core/utf8/'.__FUNCTION__.EXT;

            // Function has been called
            self::$called[__FUNCTION__] = TRUE;
        }

        return _transliterate_to_ascii($str, $case);
    }

    /**
     * Returns the length of the given string.
     * @see http://php.net/strlen
     *
     * @param   string   string being measured for length
     * @return  integer
     */
    public static function strlen($str)
    {
        if ( ! isset(self::$called[__FUNCTION__]))
        {
            require SYSPATH.'core/utf8/'.__FUNCTION__.EXT;

            // Function has been called
            self::$called[__FUNCTION__] = TRUE;
        }

        return _strlen($str);
    }

    /**
     * Finds position of first occurrence of a UTF-8 string.
     * @see http://php.net/strlen
     *
     * @author  Harry Fuecks <hfuecks@gmail.com>
     *
     * @param   string   haystack
     * @param   string   needle
     * @param   integer  offset from which character in haystack to start searching
     * @return  integer  position of needle
     * @return  boolean  FALSE if the needle is not found
     */
    public static function strpos($str, $search, $offset = 0)
    {
        if ( ! isset(self::$called[__FUNCTION__]))
        {
            require SYSPATH.'core/utf8/'.__FUNCTION__.EXT;

            // Function has been called
            self::$called[__FUNCTION__] = TRUE;
        }

        return _strpos($str, $search, $offset);
    }

    /**
     * Finds position of last occurrence of a char in a UTF-8 string.
     * @see http://php.net/strrpos
     *
     * @author  Harry Fuecks <hfuecks@gmail.com>
     *
     * @param   string   haystack
     * @param   string   needle
     * @param   integer  offset from which character in haystack to start searching
     * @return  integer  position of needle
     * @return  boolean  FALSE if the needle is not found
     */
    public static function strrpos($str, $search, $offset = 0)
    {
        if ( ! isset(self::$called[__FUNCTION__]))
        {
            require SYSPATH.'core/utf8/'.__FUNCTION__.EXT;

            // Function has been called
            self::$called[__FUNCTION__] = TRUE;
        }

        return _strrpos($str, $search, $offset);
    }

    /**
     * Returns part of a UTF-8 string.
     * @see http://php.net/substr
     *
     * @author  Chris Smith <chris@jalakai.co.uk>
     *
     * @param   string   input string
     * @param   integer  offset
     * @param   integer  length limit
     * @return  string
     */
    public static function substr($str, $offset, $length = NULL)
    {
        if ( ! isset(self::$called[__FUNCTION__]))
        {
            require SYSPATH.'core/utf8/'.__FUNCTION__.EXT;

            // Function has been called
            self::$called[__FUNCTION__] = TRUE;
        }

        return _substr($str, $offset, $length);
    }

    /**
     * Replaces text within a portion of a UTF-8 string.
     * @see http://php.net/substr_replace
     *
     * @author  Harry Fuecks <hfuecks@gmail.com>
     *
     * @param   string   input string
     * @param   string   replacement string
     * @param   integer  offset
     * @return  string
     */
    public static function substr_replace($str, $replacement, $offset, $length = NULL)
    {
        if ( ! isset(self::$called[__FUNCTION__]))
        {
            require SYSPATH.'core/utf8/'.__FUNCTION__.EXT;

            // Function has been called
            self::$called[__FUNCTION__] = TRUE;
        }

        return _substr_replace($str, $replacement, $offset, $length);
    }

    /**
     * Makes a UTF-8 string lowercase.
     * @see http://php.net/strtolower
     *
     * @author  Andreas Gohr <andi@splitbrain.org>
     *
     * @param   string   mixed case string
     * @return  string
     */
    public static function strtolower($str)
    {
        if ( ! isset(self::$called[__FUNCTION__]))
        {
            require SYSPATH.'core/utf8/'.__FUNCTION__.EXT;

            // Function has been called
            self::$called[__FUNCTION__] = TRUE;
        }

        return _strtolower($str);
    }

    /**
     * Makes a UTF-8 string uppercase.
     * @see http://php.net/strtoupper
     *
     * @author  Andreas Gohr <andi@splitbrain.org>
     *
     * @param   string   mixed case string
     * @return  string
     */
    public static function strtoupper($str)
    {
        if ( ! isset(self::$called[__FUNCTION__]))
        {
            require SYSPATH.'core/utf8/'.__FUNCTION__.EXT;

            // Function has been called
            self::$called[__FUNCTION__] = TRUE;
        }

        return _strtoupper($str);
    }

    /**
     * Makes a UTF-8 string's first character uppercase.
     * @see http://php.net/ucfirst
     *
     * @author  Harry Fuecks <hfuecks@gmail.com>
     *
     * @param   string   mixed case string
     * @return  string
     */
    public static function ucfirst($str)
    {
        if ( ! isset(self::$called[__FUNCTION__]))
        {
            require SYSPATH.'core/utf8/'.__FUNCTION__.EXT;

            // Function has been called
            self::$called[__FUNCTION__] = TRUE;
        }

        return _ucfirst($str);
    }

    /**
     * Makes the first character of every word in a UTF-8 string uppercase.
     * @see http://php.net/ucwords
     *
     * @author  Harry Fuecks <hfuecks@gmail.com>
     *
     * @param   string   mixed case string
     * @return  string
     */
    public static function ucwords($str)
    {
        if ( ! isset(self::$called[__FUNCTION__]))
        {
            require SYSPATH.'core/utf8/'.__FUNCTION__.EXT;

            // Function has been called
            self::$called[__FUNCTION__] = TRUE;
        }

        return _ucwords($str);
    }

    /**
     * Case-insensitive UTF-8 string comparison.
     * @see http://php.net/strcasecmp
     *
     * @author  Harry Fuecks <hfuecks@gmail.com>
     *
     * @param   string   string to compare
     * @param   string   string to compare
     * @return  integer  less than 0 if str1 is less than str2
     * @return  integer  greater than 0 if str1 is greater than str2
     * @return  integer  0 if they are equal
     */
    public static function strcasecmp($str1, $str2)
    {
        if ( ! isset(self::$called[__FUNCTION__]))
        {
            require SYSPATH.'core/utf8/'.__FUNCTION__.EXT;

            // Function has been called
            self::$called[__FUNCTION__] = TRUE;
        }

        return _strcasecmp($str1, $str2);
    }

    /**
     * Returns a string or an array with all occurrences of search in subject (ignoring case).
     * replaced with the given replace value.
     * @see     http://php.net/str_ireplace
     *
     * @note    It's not fast and gets slower if $search and/or $replace are arrays.
     * @author  Harry Fuecks <hfuecks@gmail.com
     *
     * @param   string|array  text to replace
     * @param   string|array  replacement text
     * @param   string|array  subject text
     * @param   integer       number of matched and replaced needles will be returned via this parameter which is passed by reference
     * @return  string        if the input was a string
     * @return  array         if the input was an array
     */
    public static function str_ireplace($search, $replace, $str, & $count = NULL)
    {
        if ( ! isset(self::$called[__FUNCTION__]))
        {
            require SYSPATH.'core/utf8/'.__FUNCTION__.EXT;

            // Function has been called
            self::$called[__FUNCTION__] = TRUE;
        }

        return _str_ireplace($search, $replace, $str, $count);
    }

    /**
     * Case-insenstive UTF-8 version of strstr. Returns all of input string
     * from the first occurrence of needle to the end.
     * @see http://php.net/stristr
     *
     * @author Harry Fuecks <hfuecks@gmail.com>
     *
     * @param   string   input string
     * @param   string   needle
     * @return  string   matched substring if found
     * @return  boolean  FALSE if the substring was not found
     */
    public static function stristr($str, $search)
    {
        if ( ! isset(self::$called[__FUNCTION__]))
        {
            require SYSPATH.'core/utf8/'.__FUNCTION__.EXT;

            // Function has been called
            self::$called[__FUNCTION__] = TRUE;
        }

        return _stristr($str, $search);
    }

    /**
     * Finds the length of the initial segment matching mask.
     * @see http://php.net/strspn
     *
     * @author Harry Fuecks <hfuecks@gmail.com>
     *
     * @param   string   input string
     * @param   string   mask for search
     * @param   integer  start position of the string to examine
     * @param   integer  length of the string to examine
     * @return  integer  length of the initial segment that contains characters in the mask
     */
    public static function strspn($str, $mask, $offset = NULL, $length = NULL)
    {
        if ( ! isset(self::$called[__FUNCTION__]))
        {
            require SYSPATH.'core/utf8/'.__FUNCTION__.EXT;

            // Function has been called
            self::$called[__FUNCTION__] = TRUE;
        }

        return _strspn($str, $mask, $offset, $length);
    }

    /**
     * Finds the length of the initial segment not matching mask.
     * @see http://php.net/strcspn
     *
     * @author  Harry Fuecks <hfuecks@gmail.com>
     *
     * @param   string   input string
     * @param   string   mask for search
     * @param   integer  start position of the string to examine
     * @param   integer  length of the string to examine
     * @return  integer  length of the initial segment that contains characters not in the mask
     */
    public static function strcspn($str, $mask, $offset = NULL, $length = NULL)
    {
        if ( ! isset(self::$called[__FUNCTION__]))
        {
            require SYSPATH.'core/utf8/'.__FUNCTION__.EXT;

            // Function has been called
            self::$called[__FUNCTION__] = TRUE;
        }

        return _strcspn($str, $mask, $offset, $length);
    }

    /**
     * Pads a UTF-8 string to a certain length with another string.
     * @see http://php.net/str_pad
     *
     * @author  Harry Fuecks <hfuecks@gmail.com>
     *
     * @param   string   input string
     * @param   integer  desired string length after padding
     * @param   string   string to use as padding
     * @param   string   padding type: STR_PAD_RIGHT, STR_PAD_LEFT, or STR_PAD_BOTH
     * @return  string
     */
    public static function str_pad($str, $final_str_length, $pad_str = ' ', $pad_type = STR_PAD_RIGHT)
    {
        if ( ! isset(self::$called[__FUNCTION__]))
        {
            require SYSPATH.'core/utf8/'.__FUNCTION__.EXT;

            // Function has been called
            self::$called[__FUNCTION__] = TRUE;
        }

        return _str_pad($str, $final_str_length, $pad_str, $pad_type);
    }

    /**
     * Converts a UTF-8 string to an array.
     * @see http://php.net/str_split
     *
     * @author  Harry Fuecks <hfuecks@gmail.com>
     *
     * @param   string   input string
     * @param   integer  maximum length of each chunk
     * @return  array
     */
    public static function str_split($str, $split_length = 1)
    {
        if ( ! isset(self::$called[__FUNCTION__]))
        {
            require SYSPATH.'core/utf8/'.__FUNCTION__.EXT;

            // Function has been called
            self::$called[__FUNCTION__] = TRUE;
        }

        return _str_split($str, $split_length);
    }

    /**
     * Reverses a UTF-8 string.
     * @see http://php.net/strrev
     *
     * @author  Harry Fuecks <hfuecks@gmail.com>
     *
     * @param   string   string to be reversed
     * @return  string
     */
    public static function strrev($str)
    {
        if ( ! isset(self::$called[__FUNCTION__]))
        {
            require SYSPATH.'core/utf8/'.__FUNCTION__.EXT;

            // Function has been called
            self::$called[__FUNCTION__] = TRUE;
        }

        return _strrev($str);
    }

    /**
     * Strips whitespace (or other UTF-8 characters) from the beginning and
     * end of a string.
     * @see http://php.net/trim
     *
     * @author  Andreas Gohr <andi@splitbrain.org>
     *
     * @param   string   input string
     * @param   string   string of characters to remove
     * @return  string
     */
    public static function trim($str, $charlist = NULL)
    {
        if ( ! isset(self::$called[__FUNCTION__]))
        {
            require SYSPATH.'core/utf8/'.__FUNCTION__.EXT;

            // Function has been called
            self::$called[__FUNCTION__] = TRUE;
        }

        return _trim($str, $charlist);
    }

    /**
     * Strips whitespace (or other UTF-8 characters) from the beginning of a string.
     * @see http://php.net/ltrim
     *
     * @author  Andreas Gohr <andi@splitbrain.org>
     *
     * @param   string   input string
     * @param   string   string of characters to remove
     * @return  string
     */
    public static function ltrim($str, $charlist = NULL)
    {
        if ( ! isset(self::$called[__FUNCTION__]))
        {
            require SYSPATH.'core/utf8/'.__FUNCTION__.EXT;

            // Function has been called
            self::$called[__FUNCTION__] = TRUE;
        }

        return _ltrim($str, $charlist);
    }

    /**
     * Strips whitespace (or other UTF-8 characters) from the end of a string.
     * @see http://php.net/rtrim
     *
     * @author  Andreas Gohr <andi@splitbrain.org>
     *