public function readBOF($rqd_stream)
{
Helper::debug("reqd: 0x%04x", $rqd_stream);
$savpos = $this->position;
$opcode = $this->read2Bytes();
if ($opcode == MY_EOF) {
throw new XLSParserException("Unsupported format, or corrupt file: Expected BOF record; met end of file");
}
if (!in_array($opcode, Defs::$bofcodes)) {
throw new XLSParserException("Expected BOF record; found " . substr($this->mem, $savpos, 8));
}
$length = $this->read2Bytes();
if ($length == MY_EOF) {
throw new XLSParserException("Expected BOF record[1]; met end of file");
}
if ($length < 4 || $length > 20) {
throw new XLSParserException("Invalid length ({$length}) for BOF record type 0x" . dechex($opcode));
}
$padding = str_repeat("", max(0, Defs::$boflen[$opcode] - $length));
$data = $this->read($this->position, $length);
Helper::debug("getbof(): data=%s", Helper::as_hex($data));
if (strlen($data) < $length) {
throw new XLSParserException("Incomplete BOF record[2]; met end of file");
}
$data .= $padding;
$version1 = $opcode >> 8;
# <HH
list($version2, $streamtype) = array_values(unpack('v2', substr($data, 0, 4)));
Helper::debug("getbof(): op=0x%04x version2=0x%04x streamtype=0x%04x", $opcode, $version2, $streamtype);
$bof_offset = $this->position - 4 - $length;
Helper::debug("getbof(): BOF found at offset %d; savpos=%d", $bof_offset, $savpos);
$version = $build = $year = 0;
if ($version1 == 0x8) {
# <HH
list($build, $year) = array_values(unpack('v2', substr($data, 4, 4)));
if ($version2 == 0x600) {
$version = 80;
} elseif ($version2 == 0x500) {
if ($year < 1994 || in_array($build, [2412, 3218, 3321])) {
$version = 50;
} else {
$version = 70;
}
} else {
# dodgy one, created by a 3rd party tool
$arr = [0x0 => 21, 0x7 => 21, 0x200 => 21, 0x300 => 30, 0x400 => 40];
$version = isset($arr[$version2]) ? $arr[$version2] : 0;
}
} elseif (in_array($version1, [0x4, 0x2, 0x0])) {
$arr = [0x4 => 40, 0x2 => 30, 0x0 => 21];
$version = $arr[$version1];
}
if ($version == 40 && $streamtype == XL_WORKBOOK_GLOBALS_4W) {
$version = 45;
# i.e. 4W
}
Helper::debug("BOF: op=0x%04x vers=0x%04x stream=0x%04x buildid=%d buildyr=%d -> BIFF%d", $opcode, $version2, $streamtype, $build, $year, $version);
$got_globals = $streamtype == XL_WORKBOOK_GLOBALS || $version == 45 && $streamtype == XL_WORKBOOK_GLOBALS_4W;
if ($rqd_stream == XL_WORKBOOK_GLOBALS && $got_globals || $streamtype == $rqd_stream) {
return $version;
}
if ($version < 50 && $streamtype == XL_WORKSHEET) {
return $version;
}
if ($version >= 50 && $streamtype == 0x100) {
throw new XLSParserException("Workspace file - no spreadsheet data");
}
throw new XLSParserException(sprintf('BOF not workbook/worksheet: op=0x%s vers=0x%s strm=0x%s build = %d year = %d -> BIFF = %d', dechex($opcode), dechex($version2), dechex($streamtype), $build, $year, $version));
}
