File Source for bad.php

<?php
/**
* @version $Id: bad.php,v 1.1 2007/09/09 20:39:51 pitlinz Exp $
* Tools for locating / replacing bad bytes in UTF-8 strings
* The Original Code is Mozilla Communicator client code.
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1998
* the Initial Developer. All Rights Reserved.
* Ported to PHP by Henri Sivonen (http://hsivonen.iki.fi)
* Slight modifications to fit with phputf8 library by Harry Fuecks (hfuecks gmail com)
* @see http://lxr.mozilla.org/seamonkey/source/intl/uconv/src/nsUTF8ToUnicode.cpp
* @see http://lxr.mozilla.org/seamonkey/source/intl/uconv/src/nsUnicodeToUTF8.cpp
* @see http://hsivonen.iki.fi/php-utf8/
* @package utf8
* @subpackage bad
* @see utf8_is_valid
*/
//--------------------------------------------------------------------
/**
* Locates the first bad byte in a UTF-8 string returning it's
* byte index in the string
* PCRE Pattern to locate bad bytes in a UTF-8 string
* Comes from W3 FAQ: Multilingual Forms
* Note: modified to include full ASCII range including control chars
* @see http://www.w3.org/International/questions/qa-forms-utf-8
* @param string
* @return mixed integer byte index or FALSE if no bad found
* @package utf8
* @subpackage bad
*/
function utf8_bad_find($str) {
$UTF8_BAD =
'([\x00-\x7F]'. # ASCII (including control chars)
'|[\xC2-\xDF][\x80-\xBF]'. # non-overlong 2-byte
'|\xE0[\xA0-\xBF][\x80-\xBF]'. # excluding overlongs
'|[\xE1-\xEC\xEE\xEF][\x80-\xBF]{2}'. # straight 3-byte
'|\xED[\x80-\x9F][\x80-\xBF]'. # excluding surrogates
'|\xF0[\x90-\xBF][\x80-\xBF]{2}'. # planes 1-3
'|[\xF1-\xF3][\x80-\xBF]{3}'. # planes 4-15
'|\xF4[\x80-\x8F][\x80-\xBF]{2}'. # plane 16
'|(.{1}))'; # invalid byte
$pos = 0;
$badList = array();
while (preg_match('/'.$UTF8_BAD.'/S', $str, $matches)) {
$bytes = strlen($matches[0]);
if ( isset($matches[2])) {
return $pos;
}
$pos += $bytes;
$str = substr($str,$bytes);
}
return FALSE;
}
//--------------------------------------------------------------------
/**
* Locates all bad bytes in a UTF-8 string and returns a list of their
* byte index in the string
* PCRE Pattern to locate bad bytes in a UTF-8 string
* Comes from W3 FAQ: Multilingual Forms
* Note: modified to include full ASCII range including control chars
* @see http://www.w3.org/International/questions/qa-forms-utf-8
* @param string
* @return mixed array of integers or FALSE if no bad found
* @package utf8
* @subpackage bad
*/
function utf8_bad_findall($str) {
$UTF8_BAD =
'([\x00-\x7F]'. # ASCII (including control chars)
'|[\xC2-\xDF][\x80-\xBF]'. # non-overlong 2-byte
'|\xE0[\xA0-\xBF][\x80-\xBF]'. # excluding overlongs
'|[\xE1-\xEC\xEE\xEF][\x80-\xBF]{2}'. # straight 3-byte
'|\xED[\x80-\x9F][\x80-\xBF]'. # excluding surrogates
'|\xF0[\x90-\xBF][\x80-\xBF]{2}'. # planes 1-3
'|[\xF1-\xF3][\x80-\xBF]{3}'. # planes 4-15
'|\xF4[\x80-\x8F][\x80-\xBF]{2}'. # plane 16
'|(.{1}))'; # invalid byte
$pos = 0;
$badList = array();
while (preg_match('/'.$UTF8_BAD.'/S', $str, $matches)) {
$bytes = strlen($matches[0]);
if ( isset($matches[2])) {
$badList[] = $pos;
}
$pos += $bytes;
$str = substr($str,$bytes);
}
if ( count($badList) > 0 ) {
return $badList;
}
return FALSE;
}
//--------------------------------------------------------------------
/**
* Strips out any bad bytes from a UTF-8 string and returns the rest
* PCRE Pattern to locate bad bytes in a UTF-8 string
* Comes from W3 FAQ: Multilingual Forms
* Note: modified to include full ASCII range including control chars
* @see http://www.w3.org/International/questions/qa-forms-utf-8
* @param string
* @return string
* @package utf8
* @subpackage bad
*/
function utf8_bad_strip($str) {
$UTF8_BAD =
'([\x00-\x7F]'. # ASCII (including control chars)
'|[\xC2-\xDF][\x80-\xBF]'. # non-overlong 2-byte
'|\xE0[\xA0-\xBF][\x80-\xBF]'. # excluding overlongs
'|[\xE1-\xEC\xEE\xEF][\x80-\xBF]{2}'. # straight 3-byte
'|\xED[\x80-\x9F][\x80-\xBF]'. # excluding surrogates
'|\xF0[\x90-\xBF][\x80-\xBF]{2}'. # planes 1-3
'|[\xF1-\xF3][\x80-\xBF]{3}'. # planes 4-15
'|\xF4[\x80-\x8F][\x80-\xBF]{2}'. # plane 16
'|(.{1}))'; # invalid byte
ob_start();
while (preg_match('/'.$UTF8_BAD.'/S', $str, $matches)) {
if ( !isset($matches[2])) {
echo $matches[0];
}
$str = substr($str,strlen($matches[0]));
}
$result = ob_get_contents();
ob_end_clean();
return $result;
}
//--------------------------------------------------------------------
/**
* Replace bad bytes with an alternative character - ASCII character
* recommended is replacement char
* PCRE Pattern to locate bad bytes in a UTF-8 string
* Comes from W3 FAQ: Multilingual Forms
* Note: modified to include full ASCII range including control chars
* @see http://www.w3.org/International/questions/qa-forms-utf-8
* @param string to search
* @param string to replace bad bytes with (defaults to '?') - use ASCII
* @return string
* @package utf8
* @subpackage bad
*/
function utf8_bad_replace($str, $replace = '?') {
$UTF8_BAD =
'([\x00-\x7F]'. # ASCII (including control chars)
'|[\xC2-\xDF][\x80-\xBF]'. # non-overlong 2-byte
'|\xE0[\xA0-\xBF][\x80-\xBF]'. # excluding overlongs
'|[\xE1-\xEC\xEE\xEF][\x80-\xBF]{2}'. # straight 3-byte
'|\xED[\x80-\x9F][\x80-\xBF]'. # excluding surrogates
'|\xF0[\x90-\xBF][\x80-\xBF]{2}'. # planes 1-3
'|[\xF1-\xF3][\x80-\xBF]{3}'. # planes 4-15
'|\xF4[\x80-\x8F][\x80-\xBF]{2}'. # plane 16
'|(.{1}))'; # invalid byte
ob_start();
while (preg_match('/'.$UTF8_BAD.'/S', $str, $matches)) {
if ( !isset($matches[2])) {
echo $matches[0];
} else {
echo $replace;
}
$str = substr($str,strlen($matches[0]));
}
$result = ob_get_contents();
ob_end_clean();
return $result;
}
//--------------------------------------------------------------------
/**
* Return code from utf8_bad_identify() when a five octet sequence is detected.
* Note: 5 octets sequences are valid UTF-8 but are not supported by Unicode so
* do not represent a useful character
* @see utf8_bad_identify
* @package utf8
* @subpackage bad
*/
define('UTF8_BAD_5OCTET',1);
/**
* Return code from utf8_bad_identify() when a six octet sequence is detected.
* Note: 6 octets sequences are valid UTF-8 but are not supported by Unicode so
* do not represent a useful character
* @see utf8_bad_identify
* @package utf8
* @subpackage bad
*/
define('UTF8_BAD_6OCTET',2);
/**
* Return code from utf8_bad_identify().
* Invalid octet for use as start of multi-byte UTF-8 sequence
* @see utf8_bad_identify
* @package utf8
* @subpackage bad
*/
define('UTF8_BAD_SEQID',3);
/**
* Return code from utf8_bad_identify().
* From Unicode 3.1, non-shortest form is illegal
* @see utf8_bad_identify
* @package utf8
* @subpackage bad
*/
define('UTF8_BAD_NONSHORT',4);
/**
* Return code from utf8_bad_identify().
* From Unicode 3.2, surrogate characters are illegal
* @see utf8_bad_identify
* @package utf8
* @subpackage bad
*/
define('UTF8_BAD_SURROGATE',5);
/**
* Return code from utf8_bad_identify().
* Codepoints outside the Unicode range are illegal
* @see utf8_bad_identify
* @package utf8
* @subpackage bad
*/
define('UTF8_BAD_UNIOUTRANGE',6);
/**
* Return code from utf8_bad_identify().
* Incomplete multi-octet sequence
* Note: this is kind of a "catch-all"
* @see utf8_bad_identify
* @package utf8
* @subpackage bad
*/
define('UTF8_BAD_SEQINCOMPLETE',7);
//--------------------------------------------------------------------
/**
* Reports on the type of bad byte found in a UTF-8 string. Returns a
* status code on the first bad byte found
* @author <hsivonen@iki.fi>
* @param string UTF-8 encoded string
* @return mixed integer constant describing problem or FALSE if valid UTF-8
* @see utf8_bad_explain
* @see http://hsivonen.iki.fi/php-utf8/
* @package utf8
* @subpackage bad
*/
function utf8_bad_identify($str, &$i) {
$mState = 0; // cached expected number of octets after the current octet
// until the beginning of the next UTF8 character sequence
$mUcs4 = 0; // cached Unicode character
$mBytes = 1; // cached expected number of octets in the current sequence
$len = strlen($str);
for($i = 0; $i < $len; $i++) {
$in = ord($str{$i});
if ( $mState == 0) {
// When mState is zero we expect either a US-ASCII character or a
// multi-octet sequence.
if (0 == (0x80 & ($in))) {
// US-ASCII, pass straight through.
$mBytes = 1;
} else if (0xC0 == (0xE0 & ($in))) {
// First octet of 2 octet sequence
$mUcs4 = ($in);
$mUcs4 = ($mUcs4 & 0x1F) << 6;
$mState = 1;
$mBytes = 2;
} else if (0xE0 == (0xF0 & ($in))) {
// First octet of 3 octet sequence
$mUcs4 = ($in);
$mUcs4 = ($mUcs4 & 0x0F) << 12;
$mState = 2;
$mBytes = 3;
} else if (0xF0 == (0xF8 & ($in))) {
// First octet of 4 octet sequence
$mUcs4 = ($in);
$mUcs4 = ($mUcs4 & 0x07) << 18;
$mState = 3;
$mBytes = 4;
} else if (0xF8 == (0xFC & ($in))) {
/* First octet of 5 octet sequence.
*
* This is illegal because the encoded codepoint must be either
* (a) not the shortest form or
* (b) outside the Unicode range of 0-0x10FFFF.
*/
return UTF8_BAD_5OCTET;
} else if (0xFC == (0xFE & ($in))) {
// First octet of 6 octet sequence, see comments for 5 octet sequence.
return UTF8_BAD_6OCTET;
} else {
// Current octet is neither in the US-ASCII range nor a legal first
// octet of a multi-octet sequence.
return UTF8_BAD_SEQID;
}
} else {
// When mState is non-zero, we expect a continuation of the multi-octet
// sequence
if (0x80 == (0xC0 & ($in))) {
// Legal continuation.
$shift = ($mState - 1) * 6;
$tmp = $in;
$tmp = ($tmp & 0x0000003F) << $shift;
$mUcs4 |= $tmp;
/**
* End of the multi-octet sequence. mUcs4 now contains the final
* Unicode codepoint to be output
*/
if (0 == --$mState) {
// From Unicode 3.1, non-shortest form is illegal
if (((2 == $mBytes) && ($mUcs4 < 0x0080)) ||
((3 == $mBytes) && ($mUcs4 < 0x0800)) ||
((4 == $mBytes) && ($mUcs4 < 0x10000)) ) {
return UTF8_BAD_NONSHORT;
// From Unicode 3.2, surrogate characters are illegal
} else if (($mUcs4 & 0xFFFFF800) == 0xD800) {
return UTF8_BAD_SURROGATE;
// Codepoints outside the Unicode range are illegal
} else if ($mUcs4 > 0x10FFFF) {
return UTF8_BAD_UNIOUTRANGE;
}
//initialize UTF8 cache
$mState = 0;
$mUcs4 = 0;
$mBytes = 1;
}
} else {
// ((0xC0 & (*in) != 0x80) && (mState != 0))
// Incomplete multi-octet sequence.
$i--;
return UTF8_BAD_SEQINCOMPLETE;
}
}
}
if ( $mState != 0 ) {
// Incomplete multi-octet sequence.
$i--;
return UTF8_BAD_SEQINCOMPLETE;
}
// No bad octets found
$i = NULL;
return FALSE;
}
//--------------------------------------------------------------------
/**
* Takes a return code from utf8_bad_identify() are returns a message
* (in English) explaining what the problem is.
* @param int return code from utf8_bad_identify
* @return mixed string message or FALSE if return code unknown
* @see utf8_bad_identify
* @package utf8
* @subpackage bad
*/
function utf8_bad_explain($code) {
switch ($code) {
case UTF8_BAD_5OCTET:
return 'Five octet sequences are valid UTF-8 but are not supported by Unicode';
break;
case UTF8_BAD_6OCTET:
return 'Six octet sequences are valid UTF-8 but are not supported by Unicode';
break;
case UTF8_BAD_SEQID:
return 'Invalid octet for use as start of multi-byte UTF-8 sequence';
break;
case UTF8_BAD_NONSHORT:
return 'From Unicode 3.1, non-shortest form is illegal';
break;
case UTF8_BAD_SURROGATE:
return 'From Unicode 3.2, surrogate characters are illegal';
break;
case UTF8_BAD_UNIOUTRANGE:
return 'Codepoints outside the Unicode range are illegal';
break;
case UTF8_BAD_SEQINCOMPLETE:
return 'Incomplete multi-octet sequence';
break;
}
trigger_error('Unknown error code: '.$code,E_USER_WARNING);
return FALSE;
}

Source for file bad.php