restic: list pack header via ListPackHandles

Replace ListPack with ListPackHandles so callers only receive blob
handles from pack headers, not layout fields.

cmd/restic/cmd_copy_integration_test.go

@@ -103,17 +103,17 @@ func testPackAndBlobCounts(t testing.TB, gopts global.Options) (countTreePacks i
 		defer unlock()
 
 		rtest.OK(t, repo.List(context.TODO(), restic.PackFile, func(id restic.ID, size int64) error {
-			blobs, err := repo.ListPack(context.TODO(), id, size)
+			handles, err := repo.ListPackHandles(context.TODO(), id, size)
 			rtest.OK(t, err)
-			rtest.Assert(t, len(blobs) > 0, "a packfile should contain at least one blob")
+			rtest.Assert(t, len(handles) > 0, "a packfile should contain at least one blob")
 
-			switch blobs[0].Type {
+			switch handles[0].Type {
 			case restic.TreeBlob:
 				countTreePacks++
 			case restic.DataBlob:
 				countDataPacks++
 			}
-			countBlobs += len(blobs)
+			countBlobs += len(handles)
 			return nil
 		}))
 		return nil

cmd/restic/cmd_find.go

@@ -473,18 +473,18 @@ func (f *Finder) packsToBlobs(ctx context.Context, packs []string) error {
 			delete(packIDs, idStr)
 		}
 		debug.Log("Found pack %s", idStr)
-		blobs, err := f.repo.ListPack(ctx, id, size)
+		handles, err := f.repo.ListPackHandles(ctx, id, size)
 		if err != nil {
 			return err
 		}
-		for _, b := range blobs {
+		for _, h := range handles {
-			switch b.Type {
+			switch h.Type {
 			case restic.DataBlob:
-				f.blobIDs[b.ID.String()] = struct{}{}
+				f.blobIDs[h.ID.String()] = struct{}{}
 			case restic.TreeBlob:
-				f.treeIDs[b.ID.String()] = struct{}{}
+				f.treeIDs[h.ID.String()] = struct{}{}
 			default:
-				panic(fmt.Sprintf("unknown type %v in blob list", b.Type.String()))
+				panic(fmt.Sprintf("unknown type %v in blob list", h.Type.String()))
 			}
 		}
 		// Stop searching when all packs have been found

internal/repository/debug.go

@@ -49,7 +49,7 @@ func writePackDumpJSON(wr io.Writer, item any) error {
 func DumpPacks(ctx context.Context, repo *Repository, wr io.Writer, printer progress.Printer) error {
 	var m sync.Mutex
 	return restic.ParallelList(ctx, repo, restic.PackFile, repo.Connections(), func(ctx context.Context, id restic.ID, size int64) error {
-		blobs, err := repo.ListPack(ctx, id, size)
+		blobs, err := repo.listPack(ctx, id, size)
 		if err != nil {
 			printer.E("error for pack %v: %v", id.Str(), err)
 			return nil
@@ -135,7 +135,7 @@ func ExaminePack(ctx context.Context, repo *Repository, id restic.ID, opts Exami
 	printer.S("  ========================================")
 	printer.S("  inspect the pack itself")
 
-	blobs, err := repo.ListPack(ctx, id, int64(len(buf)))
+	blobs, err := repo.listPack(ctx, id, int64(len(buf)))
 	if err != nil {
 		return fmt.Errorf("pack %v: %v", id.Str(), err)
 	}

internal/repository/repack_test.go

@@ -86,13 +86,12 @@ func selectBlobs(t *testing.T, random *rand.Rand, repo restic.Repository, p floa
 	blobs := restic.NewBlobSet()
 
 	err := repo.List(context.TODO(), restic.PackFile, func(id restic.ID, size int64) error {
-		entries, err := repo.ListPack(context.TODO(), id, size)
+		handles, err := repo.ListPackHandles(context.TODO(), id, size)
 		if err != nil {
 			t.Fatalf("error listing pack %v: %v", id, err)
 		}
 
-		for _, entry := range entries {
+		for _, h := range handles {
-			h := restic.BlobHandle{ID: entry.ID, Type: entry.Type}
 			if blobs.Has(h) {
 				t.Errorf("ignoring duplicate blob %v", h)
 				return nil
@@ -100,9 +99,9 @@ func selectBlobs(t *testing.T, random *rand.Rand, repo restic.Repository, p floa
 			blobs.Insert(h)
 
 			if random.Float32() <= p {
-				list1.Insert(restic.BlobHandle{ID: entry.ID, Type: entry.Type})
+				list1.Insert(h)
 			} else {
-				list2.Insert(restic.BlobHandle{ID: entry.ID, Type: entry.Type})
+				list2.Insert(h)
 			}
 		}
 		return nil

internal/repository/repair_pack.go

@@ -76,7 +76,7 @@ func resolveBlobsForPacks(ctx context.Context, repo *Repository, ids restic.IDSe
 
 	err := repo.List(ctx, restic.PackFile, func(id restic.ID, size int64) error {
 		if ids.Has(id) {
-			blobs, err := repo.ListPack(ctx, id, size)
+			blobs, err := repo.listPack(ctx, id, size)
 			if err != nil {
 				return nil
 			}

internal/repository/repository.go

@@ -783,7 +783,7 @@ func (r *Repository) createIndexFromPacks(ctx context.Context, packsize map[rest
 	// a worker receives an pack ID from ch, reads the pack contents, and adds them to idx
 	worker := func() error {
 		for fi := range ch {
-			entries, err := r.ListPack(wgCtx, fi.ID, fi.Size)
+			entries, err := r.listPack(wgCtx, fi.ID, fi.Size)
 			if err != nil {
 				debug.Log("unable to list pack file %v", fi.ID.Str())
 				m.Lock()
@@ -964,8 +964,8 @@ func (r *Repository) List(ctx context.Context, t restic.FileType, fn func(restic
 	})
 }
 
-// ListPack returns the list of blobs saved in the pack id.
+// listPack returns blob entries from the pack file header including offsets.
-func (r *Repository) ListPack(ctx context.Context, id restic.ID, size int64) (restic.Blobs, error) {
+func (r *Repository) listPack(ctx context.Context, id restic.ID, size int64) (restic.Blobs, error) {
 	h := backend.Handle{Type: restic.PackFile, Name: id.String()}
 
 	entries, _, err := pack.List(r.Key(), backend.ReaderAt(ctx, r.be, h), size)
@@ -981,6 +981,19 @@ func (r *Repository) ListPack(ctx context.Context, id restic.ID, size int64) (re
 	return entries, err
 }
 
+// ListPackHandles returns the blob handles stored in the pack file header.
+func (r *Repository) ListPackHandles(ctx context.Context, id restic.ID, size int64) ([]restic.BlobHandle, error) {
+	blobs, err := r.listPack(ctx, id, size)
+	if err != nil {
+		return nil, err
+	}
+	handles := make([]restic.BlobHandle, len(blobs))
+	for i, blob := range blobs {
+		handles[i] = blob.BlobHandle
+	}
+	return handles, nil
+}
+
 // Delete calls backend.Delete() if implemented, and returns an error
 // otherwise.
 func (r *Repository) Delete(ctx context.Context) error {

internal/repository/repository_test.go

@@ -479,11 +479,11 @@ func TestListPack(t *testing.T) {
 		return nil
 	}))
 
-	blobs, err := repo.ListPack(context.TODO(), packID, size)
+	handles, err := repo.ListPackHandles(context.TODO(), packID, size)
 	rtest.OK(t, err)
-	rtest.Assert(t, len(blobs) == 1 && blobs[0].ID == id, "unexpected blobs in pack: %v", blobs)
+	rtest.Assert(t, len(handles) == 1 && handles[0].ID == id, "unexpected blobs in pack: %v", handles)
 
-	rtest.Assert(t, !c.Has(backend.Handle{Type: restic.PackFile, Name: packID.String()}), "tree pack should no longer be cached as ListPack does not set IsMetadata in the backend.Handle")
+	rtest.Assert(t, !c.Has(backend.Handle{Type: restic.PackFile, Name: packID.String()}), "tree pack should no longer be cached as listPack does not set IsMetadata in the backend.Handle")
 }
 
 func TestNoDoubleInit(t *testing.T) {

internal/restic/repository.go

@@ -32,8 +32,8 @@ type Repository interface {
 	// the index iteration returns immediately with ctx.Err(). This blocks any modification of the index.
 	ListBlobs(ctx context.Context, fn func(PackedBlob)) error
 	ListPacksFromIndex(ctx context.Context, packs IDSet) <-chan PackBlobs
-	// ListPack returns the list of blobs saved in the pack id.
+	// ListPackHandles returns the blob handles stored in the pack file header.
-	ListPack(ctx context.Context, id ID, packSize int64) (entries Blobs, err error)
+	ListPackHandles(ctx context.Context, id ID, packSize int64) ([]BlobHandle, error)
 
 	LoadBlob(ctx context.Context, t BlobType, id ID, buf []byte) ([]byte, error)
 	LoadBlobsFromPack(ctx context.Context, packID ID, blobs []BlobHandle, handleBlobFn func(blob BlobHandle, buf []byte, err error) error) error