func TrickleLayout(db *h.DagBuilderHelper) (*dag.Node, error) {
root := h.NewUnixfsNode()
err := db.FillNodeLayer(root)
if err != nil {
return nil, err
}
for level := 1; !db.Done(); level++ {
for i := 0; i < layerRepeat && !db.Done(); i++ {
next := h.NewUnixfsNode()
err := fillTrickleRec(db, next, level)
if err != nil {
return nil, err
}
err = root.AddChild(next, db)
if err != nil {
return nil, err
}
}
}
out, err := db.Add(root)
if err != nil {
return nil, err
}
err = db.Close()
if err != nil {
return nil, err
}
return out, nil
}
// TrickleAppend appends the data in `db` to the dag, using the Trickledag format
func TrickleAppend(ctx context.Context, base *dag.Node, db *h.DagBuilderHelper) (out *dag.Node, err_out error) {
defer func() {
if err_out == nil {
if err := db.Close(); err != nil {
err_out = err
}
}
}()
// Convert to unixfs node for working with easily
ufsn, err := h.NewUnixfsNodeFromDag(base)
if err != nil {
return nil, err
}
// Get depth of this 'tree'
n, layerProgress := trickleDepthInfo(ufsn, db.Maxlinks())
if n == 0 {
// If direct blocks not filled...
if err := db.FillNodeLayer(ufsn); err != nil {
return nil, err
}
if db.Done() {
return ufsn.GetDagNode()
}
// If continuing, our depth has increased by one
n++
}
// Last child in this node may not be a full tree, lets file it up
if err := appendFillLastChild(ctx, ufsn, n-1, layerProgress, db); err != nil {
return nil, err
}
// after appendFillLastChild, our depth is now increased by one
if !db.Done() {
n++
}
// Now, continue filling out tree like normal
for i := n; !db.Done(); i++ {
for j := 0; j < layerRepeat && !db.Done(); j++ {
next := h.NewUnixfsNode()
err := fillTrickleRec(db, next, i)
if err != nil {
return nil, err
}
err = ufsn.AddChild(next, db)
if err != nil {
return nil, err
}
}
}
return ufsn.GetDagNode()
}
func BalancedLayout(db *h.DagBuilderHelper) (node.Node, error) {
var offset uint64 = 0
var root *h.UnixfsNode
for level := 0; !db.Done(); level++ {
nroot := h.NewUnixfsNode()
db.SetPosInfo(nroot, 0)
// add our old root as a child of the new root.
if root != nil { // nil if it's the first node.
if err := nroot.AddChild(root, db); err != nil {
return nil, err
}
}
// fill it up.
if err := fillNodeRec(db, nroot, level, offset); err != nil {
return nil, err
}
offset = nroot.FileSize()
root = nroot
}
if root == nil {
root = h.NewUnixfsNode()
}
out, err := db.Add(root)
if err != nil {
return nil, err
}
err = db.Close()
if err != nil {
return nil, err
}
return out, nil
}