File Source for unicode.php

<?php
/**
* @version $Id: unicode.php,v 1.1 2007/09/09 20:39:51 pitlinz Exp $
* Tools for conversion between UTF-8 and unicode
* 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 unicode
*/
//--------------------------------------------------------------------
/**
* Takes an UTF-8 string and returns an array of ints representing the
* Unicode characters. Astral planes are supported ie. the ints in the
* output can be > 0xFFFF. Occurrances of the BOM are ignored. Surrogates
* are not allowed.
* Returns false if the input string isn't a valid UTF-8 octet sequence
* and raises a PHP error at level E_USER_WARNING
* Note: this function has been modified slightly in this library to
* trigger errors on encountering bad bytes
* @author <hsivonen@iki.fi>
* @param string UTF-8 encoded string
* @return mixed array of unicode code points or FALSE if UTF-8 invalid
* @see utf8_from_unicode
* @see http://hsivonen.iki.fi/php-utf8/
* @package utf8
* @subpackage unicode
*/
function utf8_to_unicode($str) {
$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
$out = array();
$len = strlen($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.
$out[] = $in;
$mBytes = 1;
} else if (0xC0 == (0xE0 & ($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.
* Rather than trying to resynchronize, we will carry on until the end
* of the sequence and let the later error handling code catch it.
*/
$mUcs4 = ($in);
$mUcs4 = ($mUcs4 & 0x03) << 24;
$mState = 4;
$mBytes = 5;
} else if (0xFC == (0xFE & ($in))) {
// First octet of 6 octet sequence, see comments for 5 octet sequence.
$mUcs4 = ($in);
$mUcs4 = ($mUcs4 & 1) << 30;
$mState = 5;
$mBytes = 6;
} else {
/* Current octet is neither in the US-ASCII range nor a legal first
* octet of a multi-octet sequence.
*/
trigger_error(
'utf8_to_unicode: Illegal sequence identifier '.
'in UTF-8 at byte '.$i,
E_USER_WARNING
);
return FALSE;
}
} 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) {
/*
* Check for illegal sequences and codepoints.
*/
// From Unicode 3.1, non-shortest form is illegal
if (((2 == $mBytes) && ($mUcs4 < 0x0080)) ||
((3 == $mBytes) && ($mUcs4 < 0x0800)) ||
((4 == $mBytes) && ($mUcs4 < 0x10000)) ||
(4 < $mBytes) ||
// From Unicode 3.2, surrogate characters are illegal
(($mUcs4 & 0xFFFFF800) == 0xD800) ||
// Codepoints outside the Unicode range are illegal
($mUcs4 > 0x10FFFF)) {
trigger_error(
'utf8_to_unicode: Illegal sequence or codepoint '.
'in UTF-8 at byte '.$i,
E_USER_WARNING
);
return FALSE;
}
if (0xFEFF != $mUcs4) {
// BOM is legal but we don't want to output it
$out[] = $mUcs4;
}
//initialize UTF8 cache
$mState = 0;
$mUcs4 = 0;
$mBytes = 1;
}
} else {
/**
*((0xC0 & (*in) != 0x80) && (mState != 0))
* Incomplete multi-octet sequence.
*/
trigger_error(
'utf8_to_unicode: Incomplete multi-octet '.
' sequence in UTF-8 at byte '.$i,
E_USER_WARNING
);
return FALSE;
}
}
}
return $out;
}
//--------------------------------------------------------------------
/**
* Takes an array of ints representing the Unicode characters and returns
* a UTF-8 string. Astral planes are supported ie. the ints in the
* input can be > 0xFFFF. Occurrances of the BOM are ignored. Surrogates
* are not allowed.
* Returns false if the input array contains ints that represent
* surrogates or are outside the Unicode range
* and raises a PHP error at level E_USER_WARNING
* Note: this function has been modified slightly in this library to use
* output buffering to concatenate the UTF-8 string (faster) as well as
* reference the array by it's keys
* @param array of unicode code points representing a string
* @return mixed UTF-8 string or FALSE if array contains invalid code points
* @author <hsivonen@iki.fi>
* @see utf8_to_unicode
* @see http://hsivonen.iki.fi/php-utf8/
* @package utf8
* @subpackage unicode
*/
function utf8_from_unicode($arr) {
ob_start();
foreach (array_keys($arr) as $k) {
# ASCII range (including control chars)
if ( ($arr[$k] >= 0) && ($arr[$k] <= 0x007f) ) {
echo chr($arr[$k]);
# 2 byte sequence
} else if ($arr[$k] <= 0x07ff) {
echo chr(0xc0 | ($arr[$k] >> 6));
echo chr(0x80 | ($arr[$k] & 0x003f));
# Byte order mark (skip)
} else if($arr[$k] == 0xFEFF) {
// nop -- zap the BOM
# Test for illegal surrogates
} else if ($arr[$k] >= 0xD800 && $arr[$k] <= 0xDFFF) {
// found a surrogate
trigger_error(
'utf8_from_unicode: Illegal surrogate '.
'at index: '.$k.', value: '.$arr[$k],
E_USER_WARNING
);
return FALSE;
# 3 byte sequence
} else if ($arr[$k] <= 0xffff) {
echo chr(0xe0 | ($arr[$k] >> 12));
echo chr(0x80 | (($arr[$k] >> 6) & 0x003f));
echo chr(0x80 | ($arr[$k] & 0x003f));
# 4 byte sequence
} else if ($arr[$k] <= 0x10ffff) {
echo chr(0xf0 | ($arr[$k] >> 18));
echo chr(0x80 | (($arr[$k] >> 12) & 0x3f));
echo chr(0x80 | (($arr[$k] >> 6) & 0x3f));
echo chr(0x80 | ($arr[$k] & 0x3f));
} else {
trigger_error(
'utf8_from_unicode: Codepoint out of Unicode range '.
'at index: '.$k.', value: '.$arr[$k],
E_USER_WARNING
);
// out of range
return FALSE;
}
}
$result = ob_get_contents();
ob_end_clean();
return $result;
}

Source for file unicode.php