<?php
namespace dokuwiki\Utf8;
/**
* Convert between UTF-8 and a list of Unicode Code Points
*/
class 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.
*
* If $strict is set to true the function 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>
* @author Harry Fuecks <hfuecks@gmail.com>
* @see unicode_to_utf8
* @link http://hsivonen.iki.fi/php-utf8/
* @link http://sourceforge.net/projects/phputf8/
* @todo break into less complex chunks
* @todo use exceptions instead of user errors
*
* @param string $str UTF-8 encoded string
* @param boolean $strict Check for invalid sequences?
* @return mixed array of unicode code points or false if UTF-8 invalid
*/
public static function fromUtf8($str, $strict = false)
{
$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 = [];
$len = strlen($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;
} elseif (0xC0 === (0xE0 & $in)) {
// First octet of 2 octet sequence
$mUcs4 = $in;
$mUcs4 = ($mUcs4 & 0x1F) << 6;
$mState = 1;
$mBytes = 2;
} elseif (0xE0 === (0xF0 & $in)) {
// First octet of 3 octet sequence
$mUcs4 = $in;
$mUcs4 = ($mUcs4 & 0x0F) << 12;
$mState = 2;
$mBytes = 3;
} elseif (0xF0 === (0xF8 & $in)) {
// First octet of 4 octet sequence
$mUcs4 = $in;
$mUcs4 = ($mUcs4 & 0x07) << 18;
$mState = 3;
$mBytes = 4;
} elseif (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;
} elseif (0xFC === (0xFE & $in)) {
// First octet of 6 octet sequence, see comments for 5 octet sequence.
$mUcs4 = $in;
$mUcs4 = ($mUcs4 & 1) << 30;
$mState = 5;
$mBytes = 6;
} elseif ($strict) {
/* 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;
}
} elseif (0x80 === (0xC0 & $in)) {
// When mState is non-zero, we expect a continuation of the multi-octet
// sequence
// 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
($mUcs4 > 0x10FFFF)
) {
if ($strict) {
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;
$mBytes = 1;
}
} elseif ($strict) {
/**
*((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.
*
* If $strict is set to true the function 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 $arr of unicode code points representing a string
* @param boolean $strict Check for invalid sequences?
* @return string|false UTF-8 string or false if array contains invalid code points
*
* @author <hsivonen@iki.fi>
* @author Harry Fuecks <hfuecks@gmail.com>
* @see utf8_to_unicode
* @link http://hsivonen.iki.fi/php-utf8/
* @link http://sourceforge.net/projects/phputf8/
* @todo use exceptions instead of user errors
*/
public static function toUtf8($arr, $strict = false)
{
if (!is_array($arr)) return '';
ob_start();
foreach (array_keys($arr) as $k) {
if (($arr[$k] >= 0) && ($arr[$k] <= 0x007f)) {
# ASCII range (including control chars)
echo chr($arr[$k]);
} elseif ($arr[$k] <= 0x07ff) {
# 2 byte sequence
echo chr(0xc0 | ($arr[$k] >> 6));
echo chr(0x80 | ($arr[$k] & 0x003f));
} elseif ($arr[$k] == 0xFEFF) {
# Byte order mark (skip)
// nop -- zap the BOM
} elseif ($arr[$k] >= 0xD800 && $arr[$k] <= 0xDFFF) {
# Test for illegal surrogates
// found a surrogate
if ($strict) {
trigger_error(
'unicode_to_utf8: Illegal surrogate ' .
'at index: ' . $k . ', value: ' . $arr[$k],
E_USER_WARNING
);
return false;
}
} elseif ($arr[$k] <= 0xffff) {
# 3 byte sequence
echo chr(0xe0 | ($arr[$k] >> 12));
echo chr(0x80 | (($arr[$k] >> 6) & 0x003f));
echo chr(0x80 | ($arr[$k] & 0x003f));
} elseif ($arr[$k] <= 0x10ffff) {
# 4 byte sequence
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));
} elseif ($strict) {
trigger_error(
'unicode_to_utf8: Codepoint out of Unicode range ' .
'at index: ' . $k . ', value: ' . $arr[$k],
E_USER_WARNING
);
// out of range
return false;
}
}
return ob_get_clean();
}
}