Function openReader

reader.go:190–250

(fs afero.Fs, name string)

}

func openReader(fs afero.Fs, name string) (io.ReaderAt, int64, []afero.File, error) {
	f, err := fs.Open(filepath.Clean(name))
	if err != nil {
		return nil, 0, nil, fmt.Errorf("sevenzip: error opening: %w", err)
	}

	info, err := f.Stat()
	if err != nil {
		err = errors.Join(err, f.Close())

		return nil, 0, nil, fmt.Errorf("sevenzip: error retrieving file info: %w", err)
	}

	var reader io.ReaderAt = f

	size := info.Size()
	files := []afero.File{f}

	if ext := filepath.Ext(name); ext == ".001" {
		sr := []readerutil.SizeReaderAt{io.NewSectionReader(f, 0, size)}

		for i := 2; true; i++ {
			f, err := fs.Open(fmt.Sprintf("%s.%03d", strings.TrimSuffix(name, ext), i))
			if err != nil {
				if errors.Is(err, iofs.ErrNotExist) {
					break
				}

				errs := make([]error, 0, len(files)+1)
				errs = append(errs, err)

				for _, file := range files {
					errs = append(errs, file.Close())
				}

				return nil, 0, nil, fmt.Errorf("sevenzip: error opening: %w", errors.Join(errs...))
			}

			files = append(files, f)

			info, err = f.Stat()
			if err != nil {
				errs := make([]error, 0, len(files)+1)
				errs = append(errs, err)

				for _, file := range files {
					errs = append(errs, file.Close())
				}

				return nil, 0, nil, fmt.Errorf("sevenzip: error retrieving file info: %w", errors.Join(errs...))
			}

			sr = append(sr, io.NewSectionReader(f, 0, info.Size()))
		}

		mr := readerutil.NewMultiReaderAt(sr...)
		reader, size = mr, mr.Size()
	}