restic/internal/restic/tree.go

91 lines
1.9 KiB
Go

package restic
import (
"fmt"
"sort"
"github.com/restic/restic/internal/errors"
"github.com/restic/restic/internal/debug"
)
// Tree is an ordered list of nodes.
type Tree struct {
Nodes []*Node `json:"nodes"`
}
// NewTree creates a new tree object.
func NewTree() *Tree {
return &Tree{
Nodes: []*Node{},
}
}
func (t Tree) String() string {
return fmt.Sprintf("Tree<%d nodes>", len(t.Nodes))
}
// 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(): 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(): node %d is different:", i)
debug.Log(" %#v", t.Nodes[i])
debug.Log(" %#v", other.Nodes[i])
return false
}
}
return true
}
// Insert adds a new node at the correct place in the tree.
func (t *Tree) Insert(node *Node) error {
pos, _, err := t.binarySearch(node.Name)
if err == nil {
return errors.New("node already present")
}
// 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, errors.New("named node not found")
}
// Sort sorts the nodes by name.
func (t *Tree) Sort() {
list := Nodes(t.Nodes)
sort.Sort(list)
t.Nodes = list
}
// Subtrees returns a slice of all subtree IDs of the tree.
func (t Tree) Subtrees() (trees IDs) {
for _, node := range t.Nodes {
if node.Type == "dir" && node.Subtree != nil {
trees = append(trees, *node.Subtree)
}
}
return trees
}