storage: deduplicate BoltDBBatch/MemoryBatch

BoltDB doesn't have internal batching mechanism, thus we have a substitute for
it, but this substitute is absolutely identical to MemoryBatch, so it's better
to unify them and import ac5d2f94d3 fix into the
MemoryBatch.

pkg/core/storage/boltdb_store.go

@@ -24,25 +24,6 @@ type BoltDBStore struct {
 	db *bbolt.DB
 }
 
-// BoltDBBatch simple batch implementation to satisfy the Store interface.
-type BoltDBBatch struct {
-	mem map[*[]byte][]byte
-}
-
-// Len implements the Batch interface.
-func (b *BoltDBBatch) Len() int {
-	return len(b.mem)
-}
-
-// Put implements the Batch interface.
-func (b *BoltDBBatch) Put(k, v []byte) {
-	vcopy := make([]byte, len(v))
-	copy(vcopy, v)
-	kcopy := make([]byte, len(k))
-	copy(kcopy, k)
-	b.mem[&kcopy] = vcopy
-}
-
 // NewBoltDBStore returns a new ready to use BoltDB storage with created bucket.
 func NewBoltDBStore(cfg BoltDBOptions) (*BoltDBStore, error) {
 	var opts *bbolt.Options       // should be exposed via BoltDBOptions if anything needed
@@ -94,7 +75,7 @@ func (s *BoltDBStore) Get(key []byte) (val []byte, err error) {
 func (s *BoltDBStore) PutBatch(batch Batch) error {
 	return s.db.Batch(func(tx *bbolt.Tx) error {
 		b := tx.Bucket(Bucket)
-		for k, v := range batch.(*BoltDBBatch).mem {
+		for k, v := range batch.(*MemoryBatch).m {
 			err := b.Put(*k, v)
 			if err != nil {
 				return err
@@ -122,9 +103,7 @@ func (s *BoltDBStore) Seek(key []byte, f func(k, v []byte)) {
 // Batch implements the Batch interface and returns a boltdb
 // compatible Batch.
 func (s *BoltDBStore) Batch() Batch {
-	return &BoltDBBatch{
-		mem: make(map[*[]byte][]byte),
-	}
+	return newMemoryBatch()
 }
 
 // Close releases all db resources.

pkg/core/storage/boltdb_store_test.go

@@ -12,14 +12,14 @@ import (
 
 func TestBoltDBBatch(t *testing.T) {
 	boltDB := BoltDBStore{}
-	want := &BoltDBBatch{mem: map[*[]byte][]byte{}}
+	want := &MemoryBatch{m: map[*[]byte][]byte{}}
 	if got := boltDB.Batch(); !reflect.DeepEqual(got, want) {
 		t.Errorf("BoltDB Batch() = %v, want %v", got, want)
 	}
 }
 
 func TestBoltDBBatch_Len(t *testing.T) {
-	batch := &BoltDBBatch{mem: map[*[]byte][]byte{}}
+	batch := &MemoryBatch{m: map[*[]byte][]byte{}}
 	want := len(map[*[]byte][]byte{})
 	assert.Equal(t, want, batch.Len())
 }

pkg/core/storage/memory_store.go

@@ -20,8 +20,11 @@ type MemoryBatch struct {
 
 // Put implements the Batch interface.
 func (b *MemoryBatch) Put(k, v []byte) {
-	key := &k
-	b.m[key] = v
+	vcopy := make([]byte, len(v))
+	copy(vcopy, v)
+	kcopy := make([]byte, len(k))
+	copy(kcopy, k)
+	b.m[&kcopy] = vcopy
 }
 
 // Len implements the Batch interface.
@@ -76,6 +79,11 @@ func (s *MemoryStore) Seek(key []byte, f func(k, v []byte)) {
 
 // Batch implements the Batch interface and returns a compatible Batch.
 func (s *MemoryStore) Batch() Batch {
+	return newMemoryBatch()
+}
+
+// newMemoryBatch returns new memory batch.
+func newMemoryBatch() *MemoryBatch {
 	return &MemoryBatch{
 		m: make(map[*[]byte][]byte),
 	}