neoneo-go/pkg/core/mpt/hash.go
Anna Shaleva 36808b8904 core: clone MPT node while restoring it multiple times
We need this to avoid collapse collisions. Example of such collapse
described in
https://github.com/nspcc-dev/neo-go/pull/2019#discussion_r689629704.
2021-09-07 19:43:27 +03:00

86 lines
1.7 KiB
Go

package mpt
import (
"errors"
"github.com/nspcc-dev/neo-go/pkg/io"
"github.com/nspcc-dev/neo-go/pkg/util"
)
// HashNode represents MPT's hash node.
type HashNode struct {
BaseNode
Collapsed bool
}
var _ Node = (*HashNode)(nil)
// NewHashNode returns hash node with the specified hash.
func NewHashNode(h util.Uint256) *HashNode {
return &HashNode{
BaseNode: BaseNode{
hash: h,
hashValid: true,
},
}
}
// Type implements Node interface.
func (h *HashNode) Type() NodeType { return HashT }
// Size implements Node interface.
func (h *HashNode) Size() int {
return util.Uint256Size
}
// Hash implements Node interface.
func (h *HashNode) Hash() util.Uint256 {
if !h.hashValid {
panic("can't get hash of an empty HashNode")
}
return h.hash
}
// Bytes returns serialized HashNode.
func (h *HashNode) Bytes() []byte {
return h.getBytes(h)
}
// DecodeBinary implements io.Serializable.
func (h *HashNode) DecodeBinary(r *io.BinReader) {
if h.hashValid {
h.hash.DecodeBinary(r)
}
}
// EncodeBinary implements io.Serializable.
func (h HashNode) EncodeBinary(w *io.BinWriter) {
if !h.hashValid {
return
}
w.WriteBytes(h.hash[:])
}
// MarshalJSON implements json.Marshaler.
func (h *HashNode) MarshalJSON() ([]byte, error) {
return []byte(`{"hash":"` + h.hash.StringLE() + `"}`), nil
}
// UnmarshalJSON implements json.Unmarshaler.
func (h *HashNode) UnmarshalJSON(data []byte) error {
var obj NodeObject
if err := obj.UnmarshalJSON(data); err != nil {
return err
} else if u, ok := obj.Node.(*HashNode); ok {
*h = *u
return nil
}
return errors.New("expected hash node")
}
// Clone implements Node interface.
func (h *HashNode) Clone() Node {
res := *h
res.Collapsed = false
return &res
}