melder/vendor/PhpSpreadsheet/Shared/OLE/ChainedBlockStream.php

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2024-02-16 15:35:01 +01:00
<?php
namespace PhpOffice\PhpSpreadsheet\Shared\OLE;
use PhpOffice\PhpSpreadsheet\Shared\OLE;
class ChainedBlockStream
{
/**
* The OLE container of the file that is being read.
*
* @var OLE
*/
public $ole;
/**
* Parameters specified by fopen().
*
* @var array
*/
public $params;
/**
* The binary data of the file.
*
* @var string
*/
public $data;
/**
* The file pointer.
*
* @var int byte offset
*/
public $pos;
/**
* Implements support for fopen().
* For creating streams using this wrapper, use OLE_PPS_File::getStream().
*
* @param string $path resource name including scheme, e.g.
* ole-chainedblockstream://oleInstanceId=1
* @param string $mode only "r" is supported
* @param int $options mask of STREAM_REPORT_ERRORS and STREAM_USE_PATH
* @param string &$openedPath absolute path of the opened stream (out parameter)
*
* @return bool true on success
*/
public function stream_open($path, $mode, $options, &$openedPath) // @codingStandardsIgnoreLine
{
if ($mode != 'r') {
if ($options & STREAM_REPORT_ERRORS) {
trigger_error('Only reading is supported', E_USER_WARNING);
}
return false;
}
// 25 is length of "ole-chainedblockstream://"
parse_str(substr($path, 25), $this->params);
if (!isset($this->params['oleInstanceId'], $this->params['blockId'], $GLOBALS['_OLE_INSTANCES'][$this->params['oleInstanceId']])) {
if ($options & STREAM_REPORT_ERRORS) {
trigger_error('OLE stream not found', E_USER_WARNING);
}
return false;
}
$this->ole = $GLOBALS['_OLE_INSTANCES'][$this->params['oleInstanceId']];
$blockId = $this->params['blockId'];
$this->data = '';
if (isset($this->params['size']) && $this->params['size'] < $this->ole->bigBlockThreshold && $blockId != $this->ole->root->startBlock) {
// Block id refers to small blocks
$rootPos = $this->ole->getBlockOffset($this->ole->root->startBlock);
while ($blockId != -2) {
$pos = $rootPos + $blockId * $this->ole->bigBlockSize;
$blockId = $this->ole->sbat[$blockId];
fseek($this->ole->_file_handle, $pos);
$this->data .= fread($this->ole->_file_handle, $this->ole->bigBlockSize);
}
} else {
// Block id refers to big blocks
while ($blockId != -2) {
$pos = $this->ole->getBlockOffset($blockId);
fseek($this->ole->_file_handle, $pos);
$this->data .= fread($this->ole->_file_handle, $this->ole->bigBlockSize);
$blockId = $this->ole->bbat[$blockId];
}
}
if (isset($this->params['size'])) {
$this->data = substr($this->data, 0, $this->params['size']);
}
if ($options & STREAM_USE_PATH) {
$openedPath = $path;
}
return true;
}
/**
* Implements support for fclose().
*/
public function stream_close(): void // @codingStandardsIgnoreLine
{
$this->ole = null;
unset($GLOBALS['_OLE_INSTANCES']);
}
/**
* Implements support for fread(), fgets() etc.
*
* @param int $count maximum number of bytes to read
*
* @return string
*/
public function stream_read($count) // @codingStandardsIgnoreLine
{
if ($this->stream_eof()) {
return false;
}
$s = substr($this->data, $this->pos, $count);
$this->pos += $count;
return $s;
}
/**
* Implements support for feof().
*
* @return bool TRUE if the file pointer is at EOF; otherwise FALSE
*/
public function stream_eof() // @codingStandardsIgnoreLine
{
return $this->pos >= strlen($this->data);
}
/**
* Returns the position of the file pointer, i.e. its offset into the file
* stream. Implements support for ftell().
*
* @return int
*/
public function stream_tell() // @codingStandardsIgnoreLine
{
return $this->pos;
}
/**
* Implements support for fseek().
*
* @param int $offset byte offset
* @param int $whence SEEK_SET, SEEK_CUR or SEEK_END
*
* @return bool
*/
public function stream_seek($offset, $whence) // @codingStandardsIgnoreLine
{
if ($whence == SEEK_SET && $offset >= 0) {
$this->pos = $offset;
} elseif ($whence == SEEK_CUR && -$offset <= $this->pos) {
$this->pos += $offset;
} elseif ($whence == SEEK_END && -$offset <= count($this->data)) {
$this->pos = strlen($this->data) + $offset;
} else {
return false;
}
return true;
}
/**
* Implements support for fstat(). Currently the only supported field is
* "size".
*
* @return array
*/
public function stream_stat() // @codingStandardsIgnoreLine
{
return [
'size' => strlen($this->data),
];
}
// Methods used by stream_wrapper_register() that are not implemented:
// bool stream_flush ( void )
// int stream_write ( string data )
// bool rename ( string path_from, string path_to )
// bool mkdir ( string path, int mode, int options )
// bool rmdir ( string path, int options )
// bool dir_opendir ( string path, int options )
// array url_stat ( string path, int flags )
// string dir_readdir ( void )
// bool dir_rewinddir ( void )
// bool dir_closedir ( void )
}