package restic import ( "errors" "fmt" "sort" "github.com/restic/restic/backend" "github.com/restic/restic/debug" "github.com/restic/restic/pack" "github.com/restic/restic/repo" ) type Tree struct { Nodes []*Node `json:"nodes"` } var ( ErrNodeNotFound = errors.New("named node not found") ErrNodeAlreadyInTree = errors.New("node already present") ) func NewTree() *Tree { return &Tree{ Nodes: []*Node{}, } } func (t Tree) String() string { return fmt.Sprintf("Tree<%d nodes>", len(t.Nodes)) } func LoadTree(repo *repo.Repo, id backend.ID) (*Tree, error) { tree := &Tree{} err := repo.LoadJSONPack(pack.Tree, id, tree) if err != nil { return nil, err } return tree, nil } // Equals returns true if t and other have exactly the same nodes. func (t Tree) Equals(other *Tree) bool { if len(t.Nodes) != len(other.Nodes) { debug.Log("Tree.Equals", "tree.Equals(): trees have different number of nodes") return false } for i := 0; i < len(t.Nodes); i++ { if !t.Nodes[i].Equals(*other.Nodes[i]) { debug.Log("Tree.Equals", "tree.Equals(): node %d is different:", i) debug.Log("Tree.Equals", " %#v", t.Nodes[i]) debug.Log("Tree.Equals", " %#v", other.Nodes[i]) return false } } return true } func (t *Tree) Insert(node *Node) error { pos, _, err := t.binarySearch(node.Name) if err == nil { return ErrNodeAlreadyInTree } // https://code.google.com/p/go-wiki/wiki/SliceTricks t.Nodes = append(t.Nodes, &Node{}) copy(t.Nodes[pos+1:], t.Nodes[pos:]) t.Nodes[pos] = node return nil } func (t Tree) binarySearch(name string) (int, *Node, error) { pos := sort.Search(len(t.Nodes), func(i int) bool { return t.Nodes[i].Name >= name }) if pos < len(t.Nodes) && t.Nodes[pos].Name == name { return pos, t.Nodes[pos], nil } return pos, nil, ErrNodeNotFound } func (t Tree) Find(name string) (*Node, error) { _, node, err := t.binarySearch(name) return node, err }