| 356 | } |
| 357 | |
| 358 | func (s *Store) commit(ctx context.Context, fn func() error, entries ...Entry) error { |
| 359 | serializer := bsupbytes.NewSerializer() |
| 360 | serializer.Decorate(sup.StylePackage) |
| 361 | for _, e := range entries { |
| 362 | if err := serializer.Write(e); err != nil { |
| 363 | return err |
| 364 | } |
| 365 | } |
| 366 | if err := serializer.Close(); err != nil { |
| 367 | return err |
| 368 | } |
| 369 | for range maxRetries { |
| 370 | if err := s.load(ctx); err != nil { |
| 371 | return err |
| 372 | } |
| 373 | s.mu.RLock() |
| 374 | at := s.at |
| 375 | err := fn() |
| 376 | s.mu.RUnlock() |
| 377 | if err != nil { |
| 378 | return err |
| 379 | } |
| 380 | if err := s.journal.CommitAt(ctx, at, serializer.Bytes()); err != nil { |
| 381 | if os.IsExist(err) { |
| 382 | time.Sleep(time.Millisecond) |
| 383 | continue |
| 384 | } |
| 385 | return err |
| 386 | } |
| 387 | // Force a reload after a change. |
| 388 | s.mu.Lock() |
| 389 | s.at = Nil |
| 390 | s.mu.Unlock() |
| 391 | return nil |
| 392 | } |
| 393 | return ErrRetriesExceeded |
| 394 | } |
| 395 | |
| 396 | func (s *Store) MoveTail(ctx context.Context, newTail ID) error { |
| 397 | head, tail, base, err := s.journal.Boundaries(ctx) |