package backend import ( "bytes" "context" "io" "github.com/restic/restic/internal/restic" ) // LoadAll reads all data stored in the backend for the handle into the given // buffer, which is truncated. If the buffer is not large enough or nil, a new // one is allocated. func LoadAll(ctx context.Context, buf []byte, be restic.Backend, h restic.Handle) ([]byte, error) { err := be.Load(ctx, h, 0, 0, func(rd io.Reader) error { // make sure this is idempotent, in case an error occurs this function may be called multiple times! wr := bytes.NewBuffer(buf[:0]) _, cerr := io.Copy(wr, rd) if cerr != nil { return cerr } buf = wr.Bytes() return nil }) if err != nil { return nil, err } return buf, nil } // LimitedReadCloser wraps io.LimitedReader and exposes the Close() method. type LimitedReadCloser struct { io.Closer io.LimitedReader } // LimitReadCloser returns a new reader wraps r in an io.LimitedReader, but also // exposes the Close() method. func LimitReadCloser(r io.ReadCloser, n int64) *LimitedReadCloser { return &LimitedReadCloser{Closer: r, LimitedReader: io.LimitedReader{R: r, N: n}} } // DefaultLoad implements Backend.Load using lower-level openReader func func DefaultLoad(ctx context.Context, h restic.Handle, length int, offset int64, openReader func(ctx context.Context, h restic.Handle, length int, offset int64) (io.ReadCloser, error), fn func(rd io.Reader) error) error { rd, err := openReader(ctx, h, length, offset) if err != nil { return err } err = fn(rd) if err != nil { rd.Close() // ignore secondary errors closing the reader return err } return rd.Close() }