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<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\Mime;
/**
* @author Fabien Potencier <fabien@symfony.com>
* @author Xavier De Cock <xdecock@gmail.com>
*
* @internal
*/
final class CharacterStream
{
/** Pre-computed for optimization */
private const UTF8_LENGTH_MAP = [
"\x00" => 1, "\x01" => 1, "\x02" => 1, "\x03" => 1, "\x04" => 1, "\x05" => 1, "\x06" => 1, "\x07" => 1,
"\x08" => 1, "\x09" => 1, "\x0a" => 1, "\x0b" => 1, "\x0c" => 1, "\x0d" => 1, "\x0e" => 1, "\x0f" => 1,
"\x10" => 1, "\x11" => 1, "\x12" => 1, "\x13" => 1, "\x14" => 1, "\x15" => 1, "\x16" => 1, "\x17" => 1,
"\x18" => 1, "\x19" => 1, "\x1a" => 1, "\x1b" => 1, "\x1c" => 1, "\x1d" => 1, "\x1e" => 1, "\x1f" => 1,
"\x20" => 1, "\x21" => 1, "\x22" => 1, "\x23" => 1, "\x24" => 1, "\x25" => 1, "\x26" => 1, "\x27" => 1,
"\x28" => 1, "\x29" => 1, "\x2a" => 1, "\x2b" => 1, "\x2c" => 1, "\x2d" => 1, "\x2e" => 1, "\x2f" => 1,
"\x30" => 1, "\x31" => 1, "\x32" => 1, "\x33" => 1, "\x34" => 1, "\x35" => 1, "\x36" => 1, "\x37" => 1,
"\x38" => 1, "\x39" => 1, "\x3a" => 1, "\x3b" => 1, "\x3c" => 1, "\x3d" => 1, "\x3e" => 1, "\x3f" => 1,
"\x40" => 1, "\x41" => 1, "\x42" => 1, "\x43" => 1, "\x44" => 1, "\x45" => 1, "\x46" => 1, "\x47" => 1,
"\x48" => 1, "\x49" => 1, "\x4a" => 1, "\x4b" => 1, "\x4c" => 1, "\x4d" => 1, "\x4e" => 1, "\x4f" => 1,
"\x50" => 1, "\x51" => 1, "\x52" => 1, "\x53" => 1, "\x54" => 1, "\x55" => 1, "\x56" => 1, "\x57" => 1,
"\x58" => 1, "\x59" => 1, "\x5a" => 1, "\x5b" => 1, "\x5c" => 1, "\x5d" => 1, "\x5e" => 1, "\x5f" => 1,
"\x60" => 1, "\x61" => 1, "\x62" => 1, "\x63" => 1, "\x64" => 1, "\x65" => 1, "\x66" => 1, "\x67" => 1,
"\x68" => 1, "\x69" => 1, "\x6a" => 1, "\x6b" => 1, "\x6c" => 1, "\x6d" => 1, "\x6e" => 1, "\x6f" => 1,
"\x70" => 1, "\x71" => 1, "\x72" => 1, "\x73" => 1, "\x74" => 1, "\x75" => 1, "\x76" => 1, "\x77" => 1,
"\x78" => 1, "\x79" => 1, "\x7a" => 1, "\x7b" => 1, "\x7c" => 1, "\x7d" => 1, "\x7e" => 1, "\x7f" => 1,
"\x80" => 0, "\x81" => 0, "\x82" => 0, "\x83" => 0, "\x84" => 0, "\x85" => 0, "\x86" => 0, "\x87" => 0,
"\x88" => 0, "\x89" => 0, "\x8a" => 0, "\x8b" => 0, "\x8c" => 0, "\x8d" => 0, "\x8e" => 0, "\x8f" => 0,
"\x90" => 0, "\x91" => 0, "\x92" => 0, "\x93" => 0, "\x94" => 0, "\x95" => 0, "\x96" => 0, "\x97" => 0,
"\x98" => 0, "\x99" => 0, "\x9a" => 0, "\x9b" => 0, "\x9c" => 0, "\x9d" => 0, "\x9e" => 0, "\x9f" => 0,
"\xa0" => 0, "\xa1" => 0, "\xa2" => 0, "\xa3" => 0, "\xa4" => 0, "\xa5" => 0, "\xa6" => 0, "\xa7" => 0,
"\xa8" => 0, "\xa9" => 0, "\xaa" => 0, "\xab" => 0, "\xac" => 0, "\xad" => 0, "\xae" => 0, "\xaf" => 0,
"\xb0" => 0, "\xb1" => 0, "\xb2" => 0, "\xb3" => 0, "\xb4" => 0, "\xb5" => 0, "\xb6" => 0, "\xb7" => 0,
"\xb8" => 0, "\xb9" => 0, "\xba" => 0, "\xbb" => 0, "\xbc" => 0, "\xbd" => 0, "\xbe" => 0, "\xbf" => 0,
"\xc0" => 2, "\xc1" => 2, "\xc2" => 2, "\xc3" => 2, "\xc4" => 2, "\xc5" => 2, "\xc6" => 2, "\xc7" => 2,
"\xc8" => 2, "\xc9" => 2, "\xca" => 2, "\xcb" => 2, "\xcc" => 2, "\xcd" => 2, "\xce" => 2, "\xcf" => 2,
"\xd0" => 2, "\xd1" => 2, "\xd2" => 2, "\xd3" => 2, "\xd4" => 2, "\xd5" => 2, "\xd6" => 2, "\xd7" => 2,
"\xd8" => 2, "\xd9" => 2, "\xda" => 2, "\xdb" => 2, "\xdc" => 2, "\xdd" => 2, "\xde" => 2, "\xdf" => 2,
"\xe0" => 3, "\xe1" => 3, "\xe2" => 3, "\xe3" => 3, "\xe4" => 3, "\xe5" => 3, "\xe6" => 3, "\xe7" => 3,
"\xe8" => 3, "\xe9" => 3, "\xea" => 3, "\xeb" => 3, "\xec" => 3, "\xed" => 3, "\xee" => 3, "\xef" => 3,
"\xf0" => 4, "\xf1" => 4, "\xf2" => 4, "\xf3" => 4, "\xf4" => 4, "\xf5" => 4, "\xf6" => 4, "\xf7" => 4,
"\xf8" => 5, "\xf9" => 5, "\xfa" => 5, "\xfb" => 5, "\xfc" => 6, "\xfd" => 6, "\xfe" => 0, "\xff" => 0,
];
private string $data = '';
private int $dataSize = 0;
private array $map = [];
private int $charCount = 0;
private int $currentPos = 0;
private int $fixedWidth = 0;
/**
* @param resource|string $input
*/
public function __construct($input, ?string $charset = 'utf-8')
{
$charset = strtolower(trim($charset)) ?: 'utf-8';
if ('utf-8' === $charset || 'utf8' === $charset) {
$this->fixedWidth = 0;
$this->map = ['p' => [], 'i' => []];
} else {
switch ($charset) {
// 16 bits
case 'ucs2':
case 'ucs-2':
case 'utf16':
case 'utf-16':
$this->fixedWidth = 2;
break;
// 32 bits
case 'ucs4':
case 'ucs-4':
case 'utf32':
case 'utf-32':
$this->fixedWidth = 4;
break;
// 7-8 bit charsets: (us-)?ascii, (iso|iec)-?8859-?[0-9]+, windows-?125[0-9], cp-?[0-9]+, ansi, macintosh,
// koi-?7, koi-?8-?.+, mik, (cork|t1), v?iscii
// and fallback
default:
$this->fixedWidth = 1;
}
}
if (\is_resource($input)) {
$blocks = 16372;
while (false !== $read = fread($input, $blocks)) {
$this->write($read);
}
} else {
$this->write($input);
}
}
public function read(int $length): ?string
{
if ($this->currentPos >= $this->charCount) {
return null;
}
$length = ($this->currentPos + $length > $this->charCount) ? $this->charCount - $this->currentPos : $length;
if ($this->fixedWidth > 0) {
$len = $length * $this->fixedWidth;
$ret = substr($this->data, $this->currentPos * $this->fixedWidth, $len);
$this->currentPos += $length;
} else {
$end = $this->currentPos + $length;
$end = $end > $this->charCount ? $this->charCount : $end;
$ret = '';
$start = 0;
if ($this->currentPos > 0) {
$start = $this->map['p'][$this->currentPos - 1];
}
$to = $start;
for (; $this->currentPos < $end; ++$this->currentPos) {
if (isset($this->map['i'][$this->currentPos])) {
$ret .= substr($this->data, $start, $to - $start).'?';
$start = $this->map['p'][$this->currentPos];
} else {
$to = $this->map['p'][$this->currentPos];
}
}
$ret .= substr($this->data, $start, $to - $start);
}
return $ret;
}
public function readBytes(int $length): ?array
{
if (null !== $read = $this->read($length)) {
return array_map('ord', str_split($read, 1));
}
return null;
}
public function setPointer(int $charOffset): void
{
if ($this->charCount < $charOffset) {
$charOffset = $this->charCount;
}
$this->currentPos = $charOffset;
}
public function write(string $chars): void
{
$ignored = '';
$this->data .= $chars;
if ($this->fixedWidth > 0) {
$strlen = \strlen($chars);
$ignoredL = $strlen % $this->fixedWidth;
$ignored = $ignoredL ? substr($chars, -$ignoredL) : '';
$this->charCount += ($strlen - $ignoredL) / $this->fixedWidth;
} else {
$this->charCount += $this->getUtf8CharPositions($chars, $this->dataSize, $ignored);
}
$this->dataSize = \strlen($this->data) - \strlen($ignored);
}
private function getUtf8CharPositions(string $string, int $startOffset, string &$ignoredChars): int
{
$strlen = \strlen($string);
$charPos = \count($this->map['p']);
$foundChars = 0;
$invalid = false;
for ($i = 0; $i < $strlen; ++$i) {
$char = $string[$i];
$size = self::UTF8_LENGTH_MAP[$char];
if (0 == $size) {
/* char is invalid, we must wait for a resync */
$invalid = true;
continue;
}
if ($invalid) {
/* We mark the chars as invalid and start a new char */
$this->map['p'][$charPos + $foundChars] = $startOffset + $i;
$this->map['i'][$charPos + $foundChars] = true;
++$foundChars;
$invalid = false;
}
if (($i + $size) > $strlen) {
$ignoredChars = substr($string, $i);
break;
}
for ($j = 1; $j < $size; ++$j) {
$char = $string[$i + $j];
if ($char > "\x7F" && $char < "\xC0") {
// Valid - continue parsing
} else {
/* char is invalid, we must wait for a resync */
$invalid = true;
continue 2;
}
}
/* Ok we got a complete char here */
$this->map['p'][$charPos + $foundChars] = $startOffset + $i + $size;
$i += $j - 1;
++$foundChars;
}
return $foundChars;
}
}
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