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Merge pull request #2585 from karalabe/trie-dirty-tracking

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core, core/state, trie: enterprise hand-tuned multi-level caching
This commit is contained in:
Jeffrey Wilcke 2016-05-30 23:07:51 +02:00
commit 5c39a1bb26
9 changed files with 245 additions and 134 deletions
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7
core/blockchain.go
View File

@ -819,6 +819,7 @@ func (self *BlockChain) InsertChain(chain types.Blocks) (int, error) {
tstart = time.Now()
nonceChecked = make([]bool, len(chain))
statedb *state.StateDB
)
// Start the parallel nonce verifier.
@ -885,7 +886,11 @@ func (self *BlockChain) InsertChain(chain types.Blocks) (int, error) {
// Create a new statedb using the parent block and report an
// error if it fails.
statedb, err := state.New(self.GetBlock(block.ParentHash()).Root(), self.chainDb)
if statedb == nil {
statedb, err = state.New(self.GetBlock(block.ParentHash()).Root(), self.chainDb)
} else {
err = statedb.Reset(chain[i-1].Root())
}
if err != nil {
reportBlock(block, err)
return i, err

22
core/state/statedb.go
View File

@ -68,6 +68,28 @@ func New(root common.Hash, db ethdb.Database) (*StateDB, error) {
}, nil
}
// Reset clears out all emphemeral state objects from the state db, but keeps
// the underlying state trie to avoid reloading data for the next operations.
func (self *StateDB) Reset(root common.Hash) error {
var (
err error
tr = self.trie
)
if self.trie.Hash() != root {
if tr, err = trie.NewSecure(root, self.db); err != nil {
return err
}
}
*self = StateDB{
db: self.db,
trie: tr,
stateObjects: make(map[string]*StateObject),
refund: new(big.Int),
logs: make(map[common.Hash]vm.Logs),
}
return nil
}
func (self *StateDB) StartRecord(thash, bhash common.Hash, ti int) {
self.thash = thash
self.bhash = bhash

24
trie/iterator.go
View File

@ -62,7 +62,7 @@ func (self *Iterator) next(node interface{}, key []byte, isIterStart bool) []byt
switch node := node.(type) {
case fullNode:
if len(key) > 0 {
k := self.next(node[key[0]], key[1:], isIterStart)
k := self.next(node.Children[key[0]], key[1:], isIterStart)
if k != nil {
return append([]byte{key[0]}, k...)
}
@ -74,7 +74,7 @@ func (self *Iterator) next(node interface{}, key []byte, isIterStart bool) []byt
}
for i := r; i < 16; i++ {
k := self.key(node[i])
k := self.key(node.Children[i])
if k != nil {
return append([]byte{i}, k...)
}
@ -130,12 +130,12 @@ func (self *Iterator) key(node interface{}) []byte {
}
return append(k, self.key(node.Val)...)
case fullNode:
if node[16] != nil {
self.Value = node[16].(valueNode)
if node.Children[16] != nil {
self.Value = node.Children[16].(valueNode)
return []byte{16}
}
for i := 0; i < 16; i++ {
k := self.key(node[i])
k := self.key(node.Children[i])
if k != nil {
return append([]byte{byte(i)}, k...)
}
@ -175,7 +175,7 @@ type NodeIterator struct {
// NewNodeIterator creates an post-order trie iterator.
func NewNodeIterator(trie *Trie) *NodeIterator {
if bytes.Compare(trie.Root(), emptyRoot.Bytes()) == 0 {
if trie.Hash() == emptyState {
return new(NodeIterator)
}
return &NodeIterator{trie: trie}
@ -205,9 +205,11 @@ func (it *NodeIterator) step() error {
}
// Initialize the iterator if we've just started, or pop off the old node otherwise
if len(it.stack) == 0 {
it.stack = append(it.stack, &nodeIteratorState{node: it.trie.root, child: -1})
// Always start with a collapsed root
root := it.trie.Hash()
it.stack = append(it.stack, &nodeIteratorState{node: hashNode(root[:]), child: -1})
if it.stack[0].node == nil {
return fmt.Errorf("root node missing: %x", it.trie.Root())
return fmt.Errorf("root node missing: %x", it.trie.Hash())
}
} else {
it.stack = it.stack[:len(it.stack)-1]
@ -225,11 +227,11 @@ func (it *NodeIterator) step() error {
}
if node, ok := parent.node.(fullNode); ok {
// Full node, traverse all children, then the node itself
if parent.child >= len(node) {
if parent.child >= len(node.Children) {
break
}
for parent.child++; parent.child < len(node); parent.child++ {
if current := node[parent.child]; current != nil {
for parent.child++; parent.child < len(node.Children); parent.child++ {
if current := node.Children[parent.child]; current != nil {
it.stack = append(it.stack, &nodeIteratorState{node: current, parent: ancestor, child: -1})
break
}

56
trie/node.go
View File

@ -29,18 +29,36 @@ var indices = []string{"0", "1", "2", "3", "4", "5", "6", "7", "8", "9", "a", "b
type node interface {
fstring(string) string
cache() (hashNode, bool)
}
type (
fullNode [17]node
fullNode struct {
Children [17]node // Actual trie node data to encode/decode (needs custom encoder)
hash hashNode // Cached hash of the node to prevent rehashing (may be nil)
dirty bool // Cached flag whether the node's new or already stored
}
shortNode struct {
Key []byte
Val node
hash hashNode // Cached hash of the node to prevent rehashing (may be nil)
dirty bool // Cached flag whether the node's new or already stored
}
hashNode []byte
valueNode []byte
)
// EncodeRLP encodes a full node into the consensus RLP format.
func (n fullNode) EncodeRLP(w io.Writer) error {
return rlp.Encode(w, n.Children)
}
// Cache accessors to retrieve precalculated values (avoid lengthy type switches).
func (n fullNode) cache() (hashNode, bool) { return n.hash, n.dirty }
func (n shortNode) cache() (hashNode, bool) { return n.hash, n.dirty }
func (n hashNode) cache() (hashNode, bool) { return nil, true }
func (n valueNode) cache() (hashNode, bool) { return nil, true }
// Pretty printing.
func (n fullNode) String() string { return n.fstring("") }
func (n shortNode) String() string { return n.fstring("") }
@ -49,7 +67,7 @@ func (n valueNode) String() string { return n.fstring("") }
func (n fullNode) fstring(ind string) string {
resp := fmt.Sprintf("[\n%s ", ind)
for i, node := range n {
for i, node := range n.Children {
if node == nil {
resp += fmt.Sprintf("%s: <nil> ", indices[i])
} else {
@ -68,16 +86,16 @@ func (n valueNode) fstring(ind string) string {
return fmt.Sprintf("%x ", []byte(n))
}
func mustDecodeNode(dbkey, buf []byte) node {
n, err := decodeNode(buf)
func mustDecodeNode(hash, buf []byte) node {
n, err := decodeNode(hash, buf)
if err != nil {
panic(fmt.Sprintf("node %x: %v", dbkey, err))
panic(fmt.Sprintf("node %x: %v", hash, err))
}
return n
}
// decodeNode parses the RLP encoding of a trie node.
func decodeNode(buf []byte) (node, error) {
func decodeNode(hash, buf []byte) (node, error) {
if len(buf) == 0 {
return nil, io.ErrUnexpectedEOF
}
@ -87,18 +105,18 @@ func decodeNode(buf []byte) (node, error) {
}
switch c, _ := rlp.CountValues(elems); c {
case 2:
n, err := decodeShort(elems)
n, err := decodeShort(hash, buf, elems)
return n, wrapError(err, "short")
case 17:
n, err := decodeFull(elems)
n, err := decodeFull(hash, buf, elems)
return n, wrapError(err, "full")
default:
return nil, fmt.Errorf("invalid number of list elements: %v", c)
}
}
func decodeShort(buf []byte) (node, error) {
kbuf, rest, err := rlp.SplitString(buf)
func decodeShort(hash, buf, elems []byte) (node, error) {
kbuf, rest, err := rlp.SplitString(elems)
if err != nil {
return nil, err
}
@ -109,30 +127,30 @@ func decodeShort(buf []byte) (node, error) {
if err != nil {
return nil, fmt.Errorf("invalid value node: %v", err)
}
return shortNode{key, valueNode(val)}, nil
return shortNode{key, valueNode(val), hash, false}, nil
}
r, _, err := decodeRef(rest)
if err != nil {
return nil, wrapError(err, "val")
}
return shortNode{key, r}, nil
return shortNode{key, r, hash, false}, nil
}
func decodeFull(buf []byte) (fullNode, error) {
var n fullNode
func decodeFull(hash, buf, elems []byte) (fullNode, error) {
n := fullNode{hash: hash}
for i := 0; i < 16; i++ {
cld, rest, err := decodeRef(buf)
cld, rest, err := decodeRef(elems)
if err != nil {
return n, wrapError(err, fmt.Sprintf("[%d]", i))
}
n[i], buf = cld, rest
n.Children[i], elems = cld, rest
}
val, _, err := rlp.SplitString(buf)
val, _, err := rlp.SplitString(elems)
if err != nil {
return n, err
}
if len(val) > 0 {
n[16] = valueNode(val)
n.Children[16] = valueNode(val)
}
return n, nil
}
@ -152,7 +170,7 @@ func decodeRef(buf []byte) (node, []byte, error) {
err := fmt.Errorf("oversized embedded node (size is %d bytes, want size < %d)", size, hashLen)
return nil, buf, err
}
n, err := decodeNode(buf)
n, err := decodeNode(nil, buf)
return n, rest, err
case kind == rlp.String && len(val) == 0:
// empty node

8
trie/proof.go
View File

@ -54,7 +54,7 @@ func (t *Trie) Prove(key []byte) []rlp.RawValue {
}
nodes = append(nodes, n)
case fullNode:
tn = n[key[0]]
tn = n.Children[key[0]]
key = key[1:]
nodes = append(nodes, n)
case hashNode:
@ -77,7 +77,7 @@ func (t *Trie) Prove(key []byte) []rlp.RawValue {
for i, n := range nodes {
// Don't bother checking for errors here since hasher panics
// if encoding doesn't work and we're not writing to any database.
n, _ = t.hasher.replaceChildren(n, nil)
n, _, _ = t.hasher.hashChildren(n, nil)
hn, _ := t.hasher.store(n, nil, false)
if _, ok := hn.(hashNode); ok || i == 0 {
// If the node's database encoding is a hash (or is the
@ -103,7 +103,7 @@ func VerifyProof(rootHash common.Hash, key []byte, proof []rlp.RawValue) (value
if !bytes.Equal(sha.Sum(nil), wantHash) {
return nil, fmt.Errorf("bad proof node %d: hash mismatch", i)
}
n, err := decodeNode(buf)
n, err := decodeNode(wantHash, buf)
if err != nil {
return nil, fmt.Errorf("bad proof node %d: %v", i, err)
}
@ -139,7 +139,7 @@ func get(tn node, key []byte) ([]byte, node) {
tn = n.Val
key = key[len(n.Key):]
case fullNode:
tn = n[key[0]]
tn = n.Children[key[0]]
key = key[1:]
case hashNode:
return key, n

4
trie/secure_trie.go
View File

@ -162,11 +162,11 @@ func (t *SecureTrie) CommitTo(db DatabaseWriter) (root common.Hash, err error) {
}
t.secKeyCache = make(map[string][]byte)
}
n, err := t.hashRoot(db)
n, clean, err := t.hashRoot(db)
if err != nil {
return (common.Hash{}), err
}
t.root = n
t.root = clean
return common.BytesToHash(n.(hashNode)), nil
}

13
trie/sync.go
View File

@ -75,8 +75,9 @@ func (s *TrieSync) AddSubTrie(root common.Hash, depth int, parent common.Hash, c
if root == emptyRoot {
return
}
blob, _ := s.database.Get(root.Bytes())
if local, err := decodeNode(blob); local != nil && err == nil {
key := root.Bytes()
blob, _ := s.database.Get(key)
if local, err := decodeNode(key, blob); local != nil && err == nil {
return
}
// Assemble the new sub-trie sync request
@ -152,7 +153,7 @@ func (s *TrieSync) Process(results []SyncResult) (int, error) {
continue
}
// Decode the node data content and update the request
node, err := decodeNode(item.Data)
node, err := decodeNode(item.Hash[:], item.Data)
if err != nil {
return i, err
}
@ -213,9 +214,9 @@ func (s *TrieSync) children(req *request) ([]*request, error) {
}}
case fullNode:
for i := 0; i < 17; i++ {
if node[i] != nil {
if node.Children[i] != nil {
children = append(children, child{
node: &node[i],
node: &node.Children[i],
depth: req.depth + 1,
})
}
@ -238,7 +239,7 @@ func (s *TrieSync) children(req *request) ([]*request, error) {
if node, ok := (*child.node).(hashNode); ok {
// Try to resolve the node from the local database
blob, _ := s.database.Get(node)
if local, err := decodeNode(blob); local != nil && err == nil {
if local, err := decodeNode(node[:], blob); local != nil && err == nil {
*child.node = local
continue
}

235
trie/trie.go
View File

@ -129,7 +129,7 @@ func (t *Trie) TryGet(key []byte) ([]byte, error) {
tn = n.Val
pos += len(n.Key)
case fullNode:
tn = n[key[pos]]
tn = n.Children[key[pos]]
pos++
case nil:
return nil, nil
@ -169,13 +169,13 @@ func (t *Trie) Update(key, value []byte) {
func (t *Trie) TryUpdate(key, value []byte) error {
k := compactHexDecode(key)
if len(value) != 0 {
n, err := t.insert(t.root, nil, k, valueNode(value))
_, n, err := t.insert(t.root, nil, k, valueNode(value))
if err != nil {
return err
}
t.root = n
} else {
n, err := t.delete(t.root, nil, k)
_, n, err := t.delete(t.root, nil, k)
if err != nil {
return err
}
@ -184,9 +184,12 @@ func (t *Trie) TryUpdate(key, value []byte) error {
return nil
}
func (t *Trie) insert(n node, prefix, key []byte, value node) (node, error) {
func (t *Trie) insert(n node, prefix, key []byte, value node) (bool, node, error) {
if len(key) == 0 {
return value, nil
if v, ok := n.(valueNode); ok {
return !bytes.Equal(v, value.(valueNode)), value, nil
}
return true, value, nil
}
switch n := n.(type) {
case shortNode:
@ -194,53 +197,63 @@ func (t *Trie) insert(n node, prefix, key []byte, value node) (node, error) {
// If the whole key matches, keep this short node as is
// and only update the value.
if matchlen == len(n.Key) {
nn, err := t.insert(n.Val, append(prefix, key[:matchlen]...), key[matchlen:], value)
dirty, nn, err := t.insert(n.Val, append(prefix, key[:matchlen]...), key[matchlen:], value)
if err != nil {
return nil, err
return false, nil, err
}
return shortNode{n.Key, nn}, nil
if !dirty {
return false, n, nil
}
return true, shortNode{n.Key, nn, nil, true}, nil
}
// Otherwise branch out at the index where they differ.
var branch fullNode
branch := fullNode{dirty: true}
var err error
branch[n.Key[matchlen]], err = t.insert(nil, append(prefix, n.Key[:matchlen+1]...), n.Key[matchlen+1:], n.Val)
_, branch.Children[n.Key[matchlen]], err = t.insert(nil, append(prefix, n.Key[:matchlen+1]...), n.Key[matchlen+1:], n.Val)
if err != nil {
return nil, err
return false, nil, err
}
branch[key[matchlen]], err = t.insert(nil, append(prefix, key[:matchlen+1]...), key[matchlen+1:], value)
_, branch.Children[key[matchlen]], err = t.insert(nil, append(prefix, key[:matchlen+1]...), key[matchlen+1:], value)
if err != nil {
return nil, err
return false, nil, err
}
// Replace this shortNode with the branch if it occurs at index 0.
if matchlen == 0 {
return branch, nil
return true, branch, nil
}
// Otherwise, replace it with a short node leading up to the branch.
return shortNode{key[:matchlen], branch}, nil
return true, shortNode{key[:matchlen], branch, nil, true}, nil
case fullNode:
nn, err := t.insert(n[key[0]], append(prefix, key[0]), key[1:], value)
dirty, nn, err := t.insert(n.Children[key[0]], append(prefix, key[0]), key[1:], value)
if err != nil {
return nil, err
return false, nil, err
}
n[key[0]] = nn
return n, nil
if !dirty {
return false, n, nil
}
n.Children[key[0]], n.hash, n.dirty = nn, nil, true
return true, n, nil
case nil:
return shortNode{key, value}, nil
return true, shortNode{key, value, nil, true}, nil
case hashNode:
// We've hit a part of the trie that isn't loaded yet. Load
// the node and insert into it. This leaves all child nodes on
// the path to the value in the trie.
//
// TODO: track whether insertion changed the value and keep
// n as a hash node if it didn't.
rn, err := t.resolveHash(n, prefix, key)
if err != nil {
return nil, err
return false, nil, err
}
return t.insert(rn, prefix, key, value)
dirty, nn, err := t.insert(rn, prefix, key, value)
if err != nil {
return false, nil, err
}
if !dirty {
return false, rn, nil
}
return true, nn, nil
default:
panic(fmt.Sprintf("%T: invalid node: %v", n, n))
@ -258,7 +271,7 @@ func (t *Trie) Delete(key []byte) {
// If a node was not found in the database, a MissingNodeError is returned.
func (t *Trie) TryDelete(key []byte) error {
k := compactHexDecode(key)
n, err := t.delete(t.root, nil, k)
_, n, err := t.delete(t.root, nil, k)
if err != nil {
return err
}
@ -269,23 +282,26 @@ func (t *Trie) TryDelete(key []byte) error {
// delete returns the new root of the trie with key deleted.
// It reduces the trie to minimal form by simplifying
// nodes on the way up after deleting recursively.
func (t *Trie) delete(n node, prefix, key []byte) (node, error) {
func (t *Trie) delete(n node, prefix, key []byte) (bool, node, error) {
switch n := n.(type) {
case shortNode:
matchlen := prefixLen(key, n.Key)
if matchlen < len(n.Key) {
return n, nil // don't replace n on mismatch
return false, n, nil // don't replace n on mismatch
}
if matchlen == len(key) {
return nil, nil // remove n entirely for whole matches
return true, nil, nil // remove n entirely for whole matches
}
// The key is longer than n.Key. Remove the remaining suffix
// from the subtrie. Child can never be nil here since the
// subtrie must contain at least two other values with keys
// longer than n.Key.
child, err := t.delete(n.Val, append(prefix, key[:len(n.Key)]...), key[len(n.Key):])
dirty, child, err := t.delete(n.Val, append(prefix, key[:len(n.Key)]...), key[len(n.Key):])
if err != nil {
return nil, err
return false, nil, err
}
if !dirty {
return false, n, nil
}
switch child := child.(type) {
case shortNode:
@ -295,17 +311,21 @@ func (t *Trie) delete(n node, prefix, key []byte) (node, error) {
// always creates a new slice) instead of append to
// avoid modifying n.Key since it might be shared with
// other nodes.
return shortNode{concat(n.Key, child.Key...), child.Val}, nil
return true, shortNode{concat(n.Key, child.Key...), child.Val, nil, true}, nil
default:
return shortNode{n.Key, child}, nil
return true, shortNode{n.Key, child, nil, true}, nil
}
case fullNode:
nn, err := t.delete(n[key[0]], append(prefix, key[0]), key[1:])
dirty, nn, err := t.delete(n.Children[key[0]], append(prefix, key[0]), key[1:])
if err != nil {
return nil, err
return false, nil, err
}
n[key[0]] = nn
if !dirty {
return false, n, nil
}
n.Children[key[0]], n.hash, n.dirty = nn, nil, true
// Check how many non-nil entries are left after deleting and
// reduce the full node to a short node if only one entry is
// left. Since n must've contained at least two children
@ -316,7 +336,7 @@ func (t *Trie) delete(n node, prefix, key []byte) (node, error) {
// value that is left in n or -2 if n contains at least two
// values.
pos := -1
for i, cld := range n {
for i, cld := range n.Children {
if cld != nil {
if pos == -1 {
pos = i
@ -334,37 +354,41 @@ func (t *Trie) delete(n node, prefix, key []byte) (node, error) {
// shortNode{..., shortNode{...}}. Since the entry
// might not be loaded yet, resolve it just for this
// check.
cnode, err := t.resolve(n[pos], prefix, []byte{byte(pos)})
cnode, err := t.resolve(n.Children[pos], prefix, []byte{byte(pos)})
if err != nil {
return nil, err
return false, nil, err
}
if cnode, ok := cnode.(shortNode); ok {
k := append([]byte{byte(pos)}, cnode.Key...)
return shortNode{k, cnode.Val}, nil
return true, shortNode{k, cnode.Val, nil, true}, nil
}
}
// Otherwise, n is replaced by a one-nibble short node
// containing the child.
return shortNode{[]byte{byte(pos)}, n[pos]}, nil
return true, shortNode{[]byte{byte(pos)}, n.Children[pos], nil, true}, nil
}
// n still contains at least two values and cannot be reduced.
return n, nil
return true, n, nil
case nil:
return nil, nil
return false, nil, nil
case hashNode:
// We've hit a part of the trie that isn't loaded yet. Load
// the node and delete from it. This leaves all child nodes on
// the path to the value in the trie.
//
// TODO: track whether deletion actually hit a key and keep
// n as a hash node if it didn't.
rn, err := t.resolveHash(n, prefix, key)
if err != nil {
return nil, err
return false, nil, err
}
return t.delete(rn, prefix, key)
dirty, nn, err := t.delete(rn, prefix, key)
if err != nil {
return false, nil, err
}
if !dirty {
return false, rn, nil
}
return true, nn, nil
default:
panic(fmt.Sprintf("%T: invalid node: %v (%v)", n, n, key))
@ -413,8 +437,9 @@ func (t *Trie) Root() []byte { return t.Hash().Bytes() }
// Hash returns the root hash of the trie. It does not write to the
// database and can be used even if the trie doesn't have one.
func (t *Trie) Hash() common.Hash {
root, _ := t.hashRoot(nil)
return common.BytesToHash(root.(hashNode))
hash, cached, _ := t.hashRoot(nil)
t.root = cached
return common.BytesToHash(hash.(hashNode))
}
// Commit writes all nodes to the trie's database.
@ -437,17 +462,17 @@ func (t *Trie) Commit() (root common.Hash, err error) {
// the changes made to db are written back to the trie's attached
// database before using the trie.
func (t *Trie) CommitTo(db DatabaseWriter) (root common.Hash, err error) {
n, err := t.hashRoot(db)
hash, cached, err := t.hashRoot(db)
if err != nil {
return (common.Hash{}), err
}
t.root = n
return common.BytesToHash(n.(hashNode)), nil
t.root = cached
return common.BytesToHash(hash.(hashNode)), nil
}
func (t *Trie) hashRoot(db DatabaseWriter) (node, error) {
func (t *Trie) hashRoot(db DatabaseWriter) (node, node, error) {
if t.root == nil {
return hashNode(emptyRoot.Bytes()), nil
return hashNode(emptyRoot.Bytes()), nil, nil
}
if t.hasher == nil {
t.hasher = newHasher()
@ -464,51 +489,87 @@ func newHasher() *hasher {
return &hasher{tmp: new(bytes.Buffer), sha: sha3.NewKeccak256()}
}
func (h *hasher) hash(n node, db DatabaseWriter, force bool) (node, error) {
hashed, err := h.replaceChildren(n, db)
// hash collapses a node down into a hash node, also returning a copy of the
// original node initialzied with the computed hash to replace the original one.
func (h *hasher) hash(n node, db DatabaseWriter, force bool) (node, node, error) {
// If we're not storing the node, just hashing, use avaialble cached data
if hash, dirty := n.cache(); hash != nil && (db == nil || !dirty) {
return hash, n, nil
}
// Trie not processed yet or needs storage, walk the children
collapsed, cached, err := h.hashChildren(n, db)
if err != nil {
return hashNode{}, err
return hashNode{}, n, err
}
if n, err = h.store(hashed, db, force); err != nil {
return hashNode{}, err
hashed, err := h.store(collapsed, db, force)
if err != nil {
return hashNode{}, n, err
}
return n, nil
// Cache the hash and RLP blob of the ndoe for later reuse
if hash, ok := hashed.(hashNode); ok && !force {
switch cached := cached.(type) {
case shortNode:
cached.hash = hash
if db != nil {
cached.dirty = false
}
return hashed, cached, nil
case fullNode:
cached.hash = hash
if db != nil {
cached.dirty = false
}
return hashed, cached, nil
}
}
return hashed, cached, nil
}
// hashChildren replaces child nodes of n with their hashes if the encoded
// size of the child is larger than a hash.
func (h *hasher) replaceChildren(n node, db DatabaseWriter) (node, error) {
// hashChildren replaces the children of a node with their hashes if the encoded
// size of the child is larger than a hash, returning the collapsed node as well
// as a replacement for the original node with the child hashes cached in.
func (h *hasher) hashChildren(original node, db DatabaseWriter) (node, node, error) {
var err error
switch n := n.(type) {
switch n := original.(type) {
case shortNode:
// Hash the short node's child, caching the newly hashed subtree
cached := n
cached.Key = common.CopyBytes(cached.Key)
n.Key = compactEncode(n.Key)
if _, ok := n.Val.(valueNode); !ok {
if n.Val, err = h.hash(n.Val, db, false); err != nil {
return n, err
if n.Val, cached.Val, err = h.hash(n.Val, db, false); err != nil {
return n, original, err
}
}
if n.Val == nil {
// Ensure that nil children are encoded as empty strings.
n.Val = valueNode(nil)
n.Val = valueNode(nil) // Ensure that nil children are encoded as empty strings.
}
return n, nil
return n, cached, nil
case fullNode:
// Hash the full node's children, caching the newly hashed subtrees
cached := fullNode{dirty: n.dirty}
for i := 0; i < 16; i++ {
if n[i] != nil {
if n[i], err = h.hash(n[i], db, false); err != nil {
return n, err
if n.Children[i] != nil {
if n.Children[i], cached.Children[i], err = h.hash(n.Children[i], db, false); err != nil {
return n, original, err
}
} else {
// Ensure that nil children are encoded as empty strings.
n[i] = valueNode(nil)
n.Children[i] = valueNode(nil) // Ensure that nil children are encoded as empty strings.
}
}
if n[16] == nil {
n[16] = valueNode(nil)
cached.Children[16] = n.Children[16]
if n.Children[16] == nil {
n.Children[16] = valueNode(nil)
}
return n, nil
return n, cached, nil
default:
return n, nil
// Value and hash nodes don't have children so they're left as were
return n, original, nil
}
}
@ -517,21 +578,23 @@ func (h *hasher) store(n node, db DatabaseWriter, force bool) (node, error) {
if _, isHash := n.(hashNode); n == nil || isHash {
return n, nil
}
// Generate the RLP encoding of the node
h.tmp.Reset()
if err := rlp.Encode(h.tmp, n); err != nil {
panic("encode error: " + err.Error())
}
if h.tmp.Len() < 32 && !force {
// Nodes smaller than 32 bytes are stored inside their parent.
return n, nil
return n, nil // Nodes smaller than 32 bytes are stored inside their parent
}
// Larger nodes are replaced by their hash and stored in the database.
hash, _ := n.cache()
if hash == nil {
h.sha.Reset()
h.sha.Write(h.tmp.Bytes())
key := hashNode(h.sha.Sum(nil))
if db != nil {
err := db.Put(key, h.tmp.Bytes())
return key, err
hash = hashNode(h.sha.Sum(nil))
}
return key, nil
if db != nil {
return hash, db.Put(hash, h.tmp.Bytes())
}
return hash, nil
}

2
trie/trie_test.go
View File

@ -295,7 +295,7 @@ func TestReplication(t *testing.T) {
for _, val := range vals2 {
updateString(trie2, val.k, val.v)
}
if trie2.Hash() != exp {
if hash := trie2.Hash(); hash != exp {
t.Errorf("root failure. expected %x got %x", exp, hash)
}
}