Vendor/phpspreadsheet/phpoffice/phpspreadsheet/src/PhpSpreadsheet/Shared/OLE/PPS/Root.php
public function _saveBigData($iStBlk, &$raList)
    {
        $FILE = $this->fileHandle;

        // cycle through PPS's
        $iCount = count($raList);
        for ($i = 0; $i < $iCount; ++$i) {
            if ($raList[$i]->Type != OLE::OLE_PPS_TYPE_DIR) {
                $raList[$i]->Size = $raList[$i]->getDataLen();
                if (($raList[$i]->Size >= OLE::OLE_DATA_SIZE_SMALL) || (($raList[$i]->Type == OLE::OLE_PPS_TYPE_ROOT) && isset($raList[$i]->_data))) {
                    fwrite($FILE, $raList[$i]->_data);

                    if ($raList[$i]->Size % $this->bigBlockSize) {
                        fwrite($FILE, str_repeat("\x00", $this->bigBlockSize - ($raList[$i]->Size % $this->bigBlockSize)));
                    }
                    // Set For PPS
                    $raList[$i]->startBlock = $iStBlk;
                    $iStBlk +=
                            (floor($raList[$i]->Size / $this->bigBlockSize) +
                                (($raList[$i]->Size % $this->bigBlockSize) ? 1 : 0));
                }
            }
        }
    }
public function _saveBigData($iStBlk, &$raList)
    {
        $FILE = $this->fileHandle;

        // cycle through PPS's
        $iCount = count($raList);
        for ($i = 0; $i < $iCount; ++$i) {
            if ($raList[$i]->Type != OLE::OLE_PPS_TYPE_DIR) {
                $raList[$i]->Size = $raList[$i]->getDataLen();
                if (($raList[$i]->Size >= OLE::OLE_DATA_SIZE_SMALL) || (($raList[$i]->Type == OLE::OLE_PPS_TYPE_ROOT) && isset($raList[$i]->_data))) {
                    fwrite($FILE, $raList[$i]->_data);

                    if ($raList[$i]->Size % $this->bigBlockSize) {
                        fwrite($FILE, str_repeat("\x00", $this->bigBlockSize - ($raList[$i]->Size % $this->bigBlockSize)));
                    }
                    // Set For PPS
                    $raList[$i]->startBlock = $iStBlk;
                    $iStBlk +=
                            (floor($raList[$i]->Size / $this->bigBlockSize) +
                                (($raList[$i]->Size % $this->bigBlockSize) ? 1 : 0));
                }
            }
        }
    }
Saving big data (PPS's with data bigger than \PhpOffice\PhpSpreadsheet\Shared\OLE::OLE_DATA_SIZE_SMALL).

@param int $iStBlk
@param array &$raList Reference to array of PPS's