[#1460] meta: Do not use pointers as the results

Signed-off-by: Pavel Karpy <carpawell@nspcc.ru>

pkg/local_object_storage/metabase/delete.go

@@ -50,7 +50,7 @@ type referenceNumber struct {
 type referenceCounter map[string]*referenceNumber
 
 // Delete removed object records from metabase indexes.
-func (db *DB) Delete(prm DeletePrm) (*DeleteRes, error) {
+func (db *DB) Delete(prm DeletePrm) (DeleteRes, error) {
 	err := db.boltDB.Update(func(tx *bbolt.Tx) error {
 		return db.deleteGroup(tx, prm.addrs)
 	})
@@ -61,7 +61,7 @@ func (db *DB) Delete(prm DeletePrm) (*DeleteRes, error) {
 				storagelog.OpField("metabase DELETE"))
 		}
 	}
-	return nil, err
+	return DeleteRes{}, err
 }
 
 func (db *DB) deleteGroup(tx *bbolt.Tx, addrs []oid.Address) error {

pkg/local_object_storage/metabase/exists.go

@@ -31,7 +31,7 @@ func (p *ExistsPrm) WithAddress(addr oid.Address) {
 }
 
 // Exists returns the fact that the object is in the metabase.
-func (p *ExistsRes) Exists() bool {
+func (p ExistsRes) Exists() bool {
 	return p.exists
 }
 
@@ -54,9 +54,7 @@ func Exists(db *DB, addr oid.Address) (bool, error) {
 // returns true if addr is in primary index or false if it is not.
 //
 // Returns an error of type apistatus.ObjectAlreadyRemoved if object has been placed in graveyard.
-func (db *DB) Exists(prm ExistsPrm) (res *ExistsRes, err error) {
+func (db *DB) Exists(prm ExistsPrm) (res ExistsRes, err error) {
-	res = new(ExistsRes)
-
 	err = db.boltDB.View(func(tx *bbolt.Tx) error {
 		res.exists, err = db.exists(tx, prm.addr)
 

pkg/local_object_storage/metabase/get.go

@@ -40,7 +40,7 @@ func (p *GetPrm) WithRaw(raw bool) {
 }
 
 // Header returns the requested object header.
-func (r *GetRes) Header() *objectSDK.Object {
+func (r GetRes) Header() *objectSDK.Object {
 	return r.hdr
 }
 
@@ -75,9 +75,7 @@ func GetRaw(db *DB, addr oid.Address, raw bool) (*objectSDK.Object, error) {
 //
 // Returns an error of type apistatus.ObjectNotFound if object is missing in DB.
 // Returns an error of type apistatus.ObjectAlreadyRemoved if object has been placed in graveyard.
-func (db *DB) Get(prm GetPrm) (res *GetRes, err error) {
+func (db *DB) Get(prm GetPrm) (res GetRes, err error) {
-	res = new(GetRes)
-
 	err = db.boltDB.View(func(tx *bbolt.Tx) error {
 		res.hdr, err = db.get(tx, prm.addr, true, prm.raw)
 

pkg/local_object_storage/metabase/inhume.go

@@ -66,7 +66,7 @@ var errBreakBucketForEach = errors.New("bucket ForEach break")
 //
 // Allows inhuming non-locked objects only. Returns apistatus.ObjectLocked
 // if at least one object is locked.
-func (db *DB) Inhume(prm InhumePrm) (res *InhumeRes, err error) {
+func (db *DB) Inhume(prm InhumePrm) (res InhumeRes, err error) {
 	err = db.boltDB.Update(func(tx *bbolt.Tx) error {
 		garbageBKT := tx.Bucket(garbageBucketName)
 

pkg/local_object_storage/metabase/list.go

@@ -79,9 +79,8 @@ func ListWithCursor(db *DB, count uint32, cursor *Cursor) ([]oid.Address, *Curso
 //
 // Returns ErrEndOfListing if there are no more objects to return or count
 // parameter set to zero.
-func (db *DB) ListWithCursor(prm ListPrm) (res *ListRes, err error) {
+func (db *DB) ListWithCursor(prm ListPrm) (res ListRes, err error) {
 	err = db.boltDB.View(func(tx *bbolt.Tx) error {
-		res = new(ListRes)
 		res.addrList, res.cursor, err = db.listWithCursor(tx, prm.count, prm.cursor)
 		return err
 	})

pkg/local_object_storage/metabase/movable.go

@@ -61,7 +61,7 @@ func ToMoveIt(db *DB, addr oid.Address) error {
 
 // ToMoveIt marks objects to move it into another shard. This useful for
 // faster HRW fetching.
-func (db *DB) ToMoveIt(prm ToMoveItPrm) (res *ToMoveItRes, err error) {
+func (db *DB) ToMoveIt(prm ToMoveItPrm) (res ToMoveItRes, err error) {
 	err = db.boltDB.Update(func(tx *bbolt.Tx) error {
 		toMoveIt, err := tx.CreateBucketIfNotExists(toMoveItBucketName)
 		if err != nil {
@@ -84,7 +84,7 @@ func DoNotMove(db *DB, addr oid.Address) error {
 }
 
 // DoNotMove removes `MoveIt` mark from the object.
-func (db *DB) DoNotMove(prm DoNotMovePrm) (res *DoNotMoveRes, err error) {
+func (db *DB) DoNotMove(prm DoNotMovePrm) (res DoNotMoveRes, err error) {
 	err = db.boltDB.Update(func(tx *bbolt.Tx) error {
 		toMoveIt := tx.Bucket(toMoveItBucketName)
 		if toMoveIt == nil {
@@ -108,7 +108,7 @@ func Movable(db *DB) ([]oid.Address, error) {
 }
 
 // Movable returns list of marked objects to move into other shard.
-func (db *DB) Movable(_ MovablePrm) (*MovableRes, error) {
+func (db *DB) Movable(_ MovablePrm) (MovableRes, error) {
 	var strAddrs []string
 
 	err := db.boltDB.View(func(tx *bbolt.Tx) error {
@@ -124,7 +124,7 @@ func (db *DB) Movable(_ MovablePrm) (*MovableRes, error) {
 		})
 	})
 	if err != nil {
-		return nil, err
+		return MovableRes{}, err
 	}
 
 	// we can parse strings to structures in-place, but probably it seems
@@ -135,12 +135,12 @@ func (db *DB) Movable(_ MovablePrm) (*MovableRes, error) {
 	for i := range strAddrs {
 		err = decodeAddressFromKey(&addrs[i], []byte(strAddrs[i]))
 		if err != nil {
-			return nil, fmt.Errorf("can't parse object address %v: %w",
+			return MovableRes{}, fmt.Errorf("can't parse object address %v: %w",
 				strAddrs[i], err)
 		}
 	}
 
-	return &MovableRes{
+	return MovableRes{
 		addrList: addrs,
 	}, nil
 }

pkg/local_object_storage/metabase/put.go

@@ -70,7 +70,7 @@ func Put(db *DB, obj *objectSDK.Object, id *blobovnicza.ID) error {
 // Big objects have nil blobovniczaID.
 //
 // Returns an error of type apistatus.ObjectAlreadyRemoved if object has been placed in graveyard.
-func (db *DB) Put(prm PutPrm) (res *PutRes, err error) {
+func (db *DB) Put(prm PutPrm) (res PutRes, err error) {
 	err = db.boltDB.Batch(func(tx *bbolt.Tx) error {
 		return db.put(tx, prm.obj, prm.id, nil)
 	})

pkg/local_object_storage/metabase/select.go

@@ -73,9 +73,7 @@ func Select(db *DB, cnr cid.ID, fs object.SearchFilters) ([]oid.Address, error)
 }
 
 // Select returns list of addresses of objects that match search filters.
-func (db *DB) Select(prm SelectPrm) (res *SelectRes, err error) {
+func (db *DB) Select(prm SelectPrm) (res SelectRes, err error) {
-	res = new(SelectRes)
-
 	if blindlyProcess(prm.filters) {
 		return res, nil
 	}
@@ -525,8 +523,8 @@ func (db *DB) matchSlowFilters(tx *bbolt.Tx, addr oid.Address, f object.SearchFi
 // groupFilters divides filters in two groups: fast and slow. Fast filters
 // processed by indexes and slow filters processed after by unmarshaling
 // object headers.
-func groupFilters(filters object.SearchFilters) (*filterGroup, error) {
+func groupFilters(filters object.SearchFilters) (filterGroup, error) {
-	res := &filterGroup{
+	res := filterGroup{
 		fastFilters: make(object.SearchFilters, 0, len(filters)),
 		slowFilters: make(object.SearchFilters, 0, len(filters)),
 	}
@@ -536,7 +534,7 @@ func groupFilters(filters object.SearchFilters) (*filterGroup, error) {
 		case v2object.FilterHeaderContainerID: // support deprecated field
 			err := res.cnr.DecodeString(filters[i].Value())
 			if err != nil {
-				return nil, fmt.Errorf("can't parse container id: %w", err)
+				return filterGroup{}, fmt.Errorf("can't parse container id: %w", err)
 			}
 
 			res.withCnrFilter = true

pkg/local_object_storage/metabase/small.go

@@ -48,9 +48,7 @@ func IsSmall(db *DB, addr oid.Address) (*blobovnicza.ID, error) {
 // Small objects stored in blobovnicza instances. Big objects stored in FS by
 // shallow path which is calculated from address and therefore it is not
 // indexed in metabase.
-func (db *DB) IsSmall(prm IsSmallPrm) (res *IsSmallRes, err error) {
+func (db *DB) IsSmall(prm IsSmallPrm) (res IsSmallRes, err error) {
-	res = new(IsSmallRes)
-
 	err = db.boltDB.View(func(tx *bbolt.Tx) error {
 		res.id, err = db.isSmall(tx, prm.addr)