Return errors from allocators (#22)

allocator.go

@@ -37,11 +37,14 @@ func (a *Allocator) Node(nodeAddress NodeAddress) []byte {
 }
 
 // Allocate allocates node and copies data into it.
-func (a *Allocator) Allocate(copyFrom []byte) (NodeAddress, []byte) {
+func (a *Allocator) Allocate(copyFrom []byte) (NodeAddress, []byte, error) {
 	a.lastAllocatedNode++
+	if a.lastAllocatedNode >= NodeAddress(len(a.data)) {
+		return 0, nil, errors.New("out of space")
+	}
 	node := a.Node(a.lastAllocatedNode)
 	copy(node, copyFrom)
-	return a.lastAllocatedNode, node
+	return a.lastAllocatedNode, node, nil
 }
 
 // Deallocate deallocates node.
@@ -76,24 +79,32 @@ type SnapshotAllocator struct {
 }
 
 // Allocate allocates new node.
-func (sa SnapshotAllocator) Allocate() (NodeAddress, []byte) {
-	nodeAddress, node := sa.allocator.Allocate(sa.allocator.zeroNode)
+func (sa SnapshotAllocator) Allocate() (NodeAddress, []byte, error) {
+	nodeAddress, node, err := sa.allocator.Allocate(sa.allocator.zeroNode)
+	if err != nil {
+		return 0, nil, err
+	}
+
 	sa.dirtyNodes[nodeAddress] = struct{}{}
-	return nodeAddress, node
+	return nodeAddress, node, nil
 }
 
 // Copy allocates new node and copies content from existing one.
-func (sa SnapshotAllocator) Copy(data []byte) (NodeAddress, []byte) {
-	nodeAddress, node := sa.allocator.Allocate(data)
+func (sa SnapshotAllocator) Copy(data []byte) (NodeAddress, []byte, error) {
+	nodeAddress, node, err := sa.allocator.Allocate(data)
+	if err != nil {
+		return 0, nil, err
+	}
+
 	sa.dirtyNodes[nodeAddress] = struct{}{}
-	return nodeAddress, node
+	return nodeAddress, node, nil
 }
 
 // Deallocate marks node for deallocation.
-func (sa SnapshotAllocator) Deallocate(nodeAddress NodeAddress, srcSnapshotID SnapshotID) {
+func (sa SnapshotAllocator) Deallocate(nodeAddress NodeAddress, srcSnapshotID SnapshotID) error {
 	if srcSnapshotID == sa.snapshotID {
 		sa.DeallocateImmediately(nodeAddress)
-		return
+		return nil
 	}
 
 	listNodeAddress, _ := sa.deallocationLists.Get(srcSnapshotID)
@@ -103,10 +114,16 @@ func (sa SnapshotAllocator) Deallocate(nodeAddress NodeAddress, srcSnapshotID Sn
 		NodeAllocator: sa.listNodeAllocator,
 		Allocator:     sa,
 	})
-	list.Add(nodeAddress)
+	if err := list.Add(nodeAddress); err != nil {
+		return err
+	}
 	if list.config.Item != listNodeAddress {
-		sa.deallocationLists.Set(srcSnapshotID, list.config.Item)
+		if err := sa.deallocationLists.Set(srcSnapshotID, list.config.Item); err != nil {
+			return err
+		}
 	}
+
+	return nil
 }
 
 // DeallocateImmediately dealocates node immediately.
@@ -171,15 +188,21 @@ func (na SpaceNodeAllocator[T]) Get(nodeAddress NodeAddress) ([]byte, SpaceNode[
 }
 
 // Allocate allocates new object.
-func (na SpaceNodeAllocator[T]) Allocate(allocator SnapshotAllocator) (NodeAddress, SpaceNode[T]) {
-	n, node := allocator.Allocate()
-	return n, na.project(node)
+func (na SpaceNodeAllocator[T]) Allocate(allocator SnapshotAllocator) (NodeAddress, SpaceNode[T], error) {
+	n, node, err := allocator.Allocate()
+	if err != nil {
+		return 0, SpaceNode[T]{}, err
+	}
+	return n, na.project(node), nil
 }
 
 // Copy allocates copy of existing object.
-func (na SpaceNodeAllocator[T]) Copy(allocator SnapshotAllocator, data []byte) (NodeAddress, SpaceNode[T]) {
-	n, node := allocator.Copy(data)
-	return n, na.project(node)
+func (na SpaceNodeAllocator[T]) Copy(allocator SnapshotAllocator, data []byte) (NodeAddress, SpaceNode[T], error) {
+	n, node, err := allocator.Copy(data)
+	if err != nil {
+		return 0, SpaceNode[T]{}, err
+	}
+	return n, na.project(node), nil
 }
 
 // Index returns element index based on hash.
@@ -237,15 +260,21 @@ func (na ListNodeAllocator) Get(nodeAddress NodeAddress) ([]byte, ListNode) {
 }
 
 // Allocate allocates new object.
-func (na ListNodeAllocator) Allocate(allocator SnapshotAllocator) (NodeAddress, ListNode) {
-	n, node := allocator.Allocate()
-	return n, na.project(node)
+func (na ListNodeAllocator) Allocate(allocator SnapshotAllocator) (NodeAddress, ListNode, error) {
+	n, node, err := allocator.Allocate()
+	if err != nil {
+		return 0, ListNode{}, err
+	}
+	return n, na.project(node), nil
 }
 
 // Copy allocates copy of existing object.
-func (na ListNodeAllocator) Copy(allocator SnapshotAllocator, data []byte) (NodeAddress, ListNode) {
-	n, node := allocator.Copy(data)
-	return n, na.project(node)
+func (na ListNodeAllocator) Copy(allocator SnapshotAllocator, data []byte) (NodeAddress, ListNode, error) {
+	n, node, err := allocator.Copy(data)
+	if err != nil {
+		return 0, ListNode{}, err
+	}
+	return n, na.project(node), nil
 }
 
 func (na ListNodeAllocator) project(node []byte) ListNode {

db.go

@@ -140,7 +140,9 @@ func (db *DB) DeleteSnapshot(snapshotID SnapshotID) error {
 				NodeAllocator: db.listNodeAllocator,
 			})
 			list.Deallocate(db.config.Allocator)
-			nextDeallocationLists.Delete(sID)
+			if err := nextDeallocationLists.Delete(sID); err != nil {
+				return err
+			}
 		}
 
 		// FIXME (wojciech): Iterate over space instead
@@ -154,14 +156,20 @@ func (db *DB) DeleteSnapshot(snapshotID SnapshotID) error {
 			nextList := NewList(ListConfig{
 				Item: nextListNodeAddress,
 			})
-			nextList.Attach(listNodeAddress)
+			if err := nextList.Attach(listNodeAddress); err != nil {
+				return err
+			}
 			if nextList.config.Item != nextListNodeAddress {
-				nextDeallocationLists.Set(sID, nextList.config.Item)
+				if err := nextDeallocationLists.Set(sID, nextList.config.Item); err != nil {
+					return err
+				}
 			}
 		}
 
 		nextSnapshotInfo.PreviousSnapshotID = snapshotInfo.PreviousSnapshotID
-		db.nextSnapshot.Snapshots.Set(snapshotInfo.NextSnapshotID, nextSnapshotInfo)
+		if err := db.nextSnapshot.Snapshots.Set(snapshotInfo.NextSnapshotID, nextSnapshotInfo); err != nil {
+			return err
+		}
 	}
 
 	if snapshotInfo.PreviousSnapshotID > db.nextSnapshot.SingularityNode.FirstSnapshotID {
@@ -170,7 +178,9 @@ func (db *DB) DeleteSnapshot(snapshotID SnapshotID) error {
 			return errors.Errorf("snapshot %d does not exist", snapshotID)
 		}
 		previousSnapshotInfo.NextSnapshotID = snapshotInfo.NextSnapshotID
-		db.nextSnapshot.Snapshots.Set(snapshotInfo.PreviousSnapshotID, previousSnapshotInfo)
+		if err := db.nextSnapshot.Snapshots.Set(snapshotInfo.PreviousSnapshotID, previousSnapshotInfo); err != nil {
+			return err
+		}
 	}
 
 	if snapshotID == db.nextSnapshot.SingularityNode.FirstSnapshotID {
@@ -195,14 +205,18 @@ func (db *DB) Commit() error {
 		if *spaceToCommit.PInfo.State == stateFree || *spaceToCommit.PInfo.Item == spaceToCommit.OriginalItem {
 			continue
 		}
-		db.nextSnapshot.Spaces.Set(spaceID, SpaceInfo{
+		if err := db.nextSnapshot.Spaces.Set(spaceID, SpaceInfo{
 			HashMod: *spaceToCommit.HashMod,
 			State:   *spaceToCommit.PInfo.State,
 			Node:    *spaceToCommit.PInfo.Item,
-		})
+		}); err != nil {
+			return err
+		}
 	}
 
-	db.nextSnapshot.Snapshots.Set(db.nextSnapshot.SnapshotID, *db.nextSnapshot.SnapshotInfo)
+	if err := db.nextSnapshot.Snapshots.Set(db.nextSnapshot.SnapshotID, *db.nextSnapshot.SnapshotInfo); err != nil {
+		return err
+	}
 
 	*photon.FromBytes[SingularityNode](db.config.Allocator.Node(0)) = *db.nextSnapshot.SingularityNode
 

db_test.go

@@ -24,13 +24,15 @@ var collisions = [][]int{
 }
 
 func newDB(t *testing.T) *DB {
+	requireT := require.New(t)
+
 	db, err := New(Config{
 		Allocator: NewAllocator(AllocatorConfig{
 			TotalSize: 10 * 1024 * 1024,
 			NodeSize:  512,
 		}),
 	})
-	require.NoError(t, err)
+	requireT.NoError(err)
 	return db
 }
 
@@ -47,51 +49,57 @@ func TestCollisions(t *testing.T) {
 }
 
 func TestSet(t *testing.T) {
+	requireT := require.New(t)
+
 	db := newDB(t)
 
 	space, err := GetSpace[int, int](spaceID, db)
-	require.NoError(t, err)
+	requireT.NoError(err)
 
 	for i := range 10 {
-		space.Set(i, i)
+		requireT.NoError(space.Set(i, i))
 	}
 
-	require.Equal(t, []int{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}, collect(space))
+	requireT.Equal([]int{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}, collect(space))
 }
 
 func TestSetCollisions(t *testing.T) {
+	requireT := require.New(t)
+
 	db := newDB(t)
 
 	space, err := GetSpace[int, int](spaceID, db)
-	require.NoError(t, err)
+	requireT.NoError(err)
 
 	allValues := make([]int, 0, len(collisions)*len(collisions[0]))
 
 	for _, set := range collisions {
 		for _, i := range set {
 			allValues = append(allValues, i)
-			space.Set(i, i)
+			requireT.NoError(space.Set(i, i))
 		}
 	}
 
 	sort.Ints(allValues)
 
-	require.Equal(t, allValues, collect(space))
+	requireT.Equal(allValues, collect(space))
 }
 
 func TestGetCollisions(t *testing.T) {
+	requireT := require.New(t)
+
 	db := newDB(t)
 
 	space, err := GetSpace[int, int](spaceID, db)
-	require.NoError(t, err)
+	requireT.NoError(err)
 
 	inserted := make([]int, 0, len(collisions)*len(collisions[0]))
 	read := make([]int, 0, len(collisions)*len(collisions[0]))
 
 	for _, set := range collisions {
 		for _, i := range set {
 			inserted = append(inserted, i)
-			space.Set(i, i)
+			requireT.NoError(space.Set(i, i))
 		}
 	}
 
@@ -106,7 +114,7 @@ func TestGetCollisions(t *testing.T) {
 	sort.Ints(inserted)
 	sort.Ints(read)
 
-	require.Equal(t, inserted, read)
+	requireT.Equal(inserted, read)
 }
 
 func TestSetOnNext(t *testing.T) {
@@ -118,7 +126,7 @@ func TestSetOnNext(t *testing.T) {
 	requireT.NoError(err)
 
 	for i := range 10 {
-		space1.Set(i, i)
+		requireT.NoError(space1.Set(i, i))
 	}
 
 	requireT.NoError(db.Commit())
@@ -127,7 +135,7 @@ func TestSetOnNext(t *testing.T) {
 	requireT.NoError(err)
 
 	for i := range 5 {
-		space2.Set(i, i+10)
+		requireT.NoError(space2.Set(i, i+10))
 	}
 
 	requireT.Equal([]int{0, 1, 2, 3, 4, 5, 6, 7, 8, 9}, collect(space1))
@@ -143,7 +151,7 @@ func TestGet(t *testing.T) {
 	requireT.NoError(err)
 
 	for i := range 10 {
-		space.Set(i, i)
+		requireT.NoError(space.Set(i, i))
 	}
 	for i := range 10 {
 		v, exists := space.Get(i)
@@ -161,7 +169,7 @@ func TestReplace(t *testing.T) {
 	requireT.NoError(err)
 
 	for i := range 10 {
-		space1.Set(i, i)
+		requireT.NoError(space1.Set(i, i))
 	}
 
 	requireT.NoError(db.Commit())
@@ -170,7 +178,7 @@ func TestReplace(t *testing.T) {
 	requireT.NoError(err)
 
 	for i, j := 0, 10; i < 5; i, j = i+1, j+1 {
-		space2.Set(i, j)
+		requireT.NoError(space2.Set(i, j))
 	}
 
 	for i := range 10 {