package restic import ( "context" "sync" "github.com/restic/restic/internal/ui/progress" "golang.org/x/sync/errgroup" ) // Loader loads a blob from a repository. type Loader interface { LoadBlob(context.Context, BlobType, ID, []byte) ([]byte, error) LookupBlobSize(tpe BlobType, id ID) (uint, bool) Connections() uint } type FindBlobSet interface { Has(bh BlobHandle) bool Insert(bh BlobHandle) } // FindUsedBlobs traverses the tree ID and adds all seen blobs (trees and data // blobs) to the set blobs. Already seen tree blobs will not be visited again. func FindUsedBlobs(ctx context.Context, repo Loader, treeIDs IDs, blobs FindBlobSet, p *progress.Counter) error { var lock sync.Mutex wg, ctx := errgroup.WithContext(ctx) treeStream := StreamTrees(ctx, wg, repo, treeIDs, func(treeID ID) bool { // locking is necessary the goroutine below concurrently adds data blobs lock.Lock() h := BlobHandle{ID: treeID, Type: TreeBlob} blobReferenced := blobs.Has(h) // noop if already referenced blobs.Insert(h) lock.Unlock() return blobReferenced }, p) wg.Go(func() error { for tree := range treeStream { if tree.Error != nil { return tree.Error } lock.Lock() for _, node := range tree.Nodes { switch node.Type { case NodeTypeFile: for _, blob := range node.Content { blobs.Insert(BlobHandle{ID: blob, Type: DataBlob}) } } } lock.Unlock() } return nil }) return wg.Wait() }