PHPOffice / PhpSpreadsheet

        // ----- Go to the end of the zip file

        $v_size = filesize($this->zipname);

        @fseek($this->zip_fd, $v_size);

        if (@ftell($this->zip_fd) != $v_size) {

            // ----- Error log

            self::privErrorLog(PCLZIP_ERR_BAD_FORMAT, 'Unable to go to the end of the archive \'' . $this->zipname . '\'');

            // ----- Return

            return self::errorCode();

        }

        // ----- First try : look if this is an archive with no commentaries (most of the time)

        // in this case the end of central dir is at 22 bytes of the file end

        $v_found = 0;

        if ($v_size > 26) {

            @fseek($this->zip_fd, $v_size - 22);

            if (($v_pos = @ftell($this->zip_fd)) != ($v_size - 22)) {

                // ----- Error log

                self::privErrorLog(PCLZIP_ERR_BAD_FORMAT, 'Unable to seek back to the middle of the archive \'' . $this->zipname . '\'');

                // ----- Return

                return self::errorCode();

            }

            // ----- Read for bytes

            $v_binary_data = @fread($this->zip_fd, 4);

                $v_maximum_size = $v_size;

            }

            @fseek($this->zip_fd, $v_size - $v_maximum_size);

            if (@ftell($this->zip_fd) != ($v_size - $v_maximum_size)) {

                // ----- Error log

                self::privErrorLog(PCLZIP_ERR_BAD_FORMAT, 'Unable to seek back to the middle of the archive \'' . $this->zipname . '\'');

                // ----- Return

                return self::errorCode();

            }

            // ----- Read byte per byte in order to find the signature

            $v_pos = ftell($this->zip_fd);