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-rw-r--r--ethtrie/trie.go609
1 files changed, 609 insertions, 0 deletions
diff --git a/ethtrie/trie.go b/ethtrie/trie.go
new file mode 100644
index 000000000..7a86e79bd
--- /dev/null
+++ b/ethtrie/trie.go
@@ -0,0 +1,609 @@
+package ethtrie
+
+import (
+ "bytes"
+ "fmt"
+ _ "reflect"
+ "sync"
+
+ "github.com/ethereum/go-ethereum/ethcrypto"
+ "github.com/ethereum/go-ethereum/ethutil"
+)
+
+func __ignore() { fmt.Println("") }
+
+func ParanoiaCheck(t1 *Trie) (bool, *Trie) {
+ t2 := New(ethutil.Config.Db, "")
+
+ t1.NewIterator().Each(func(key string, v *ethutil.Value) {
+ t2.Update(key, v.Str())
+ })
+
+ a := ethutil.NewValue(t2.Root).Bytes()
+ b := ethutil.NewValue(t1.Root).Bytes()
+
+ return bytes.Compare(a, b) == 0, t2
+}
+
+func (s *Cache) Len() int {
+ return len(s.nodes)
+}
+
+// TODO
+// A StateObject is an object that has a state root
+// This is goig to be the object for the second level caching (the caching of object which have a state such as contracts)
+type StateObject interface {
+ State() *Trie
+ Sync()
+ Undo()
+}
+
+type Node struct {
+ Key []byte
+ Value *ethutil.Value
+ Dirty bool
+}
+
+func NewNode(key []byte, val *ethutil.Value, dirty bool) *Node {
+ return &Node{Key: key, Value: val, Dirty: dirty}
+}
+
+func (n *Node) Copy() *Node {
+ return NewNode(n.Key, n.Value, n.Dirty)
+}
+
+type Cache struct {
+ nodes map[string]*Node
+ db ethutil.Database
+ IsDirty bool
+}
+
+func NewCache(db ethutil.Database) *Cache {
+ return &Cache{db: db, nodes: make(map[string]*Node)}
+}
+
+func (cache *Cache) PutValue(v interface{}, force bool) interface{} {
+ value := ethutil.NewValue(v)
+
+ enc := value.Encode()
+ if len(enc) >= 32 || force {
+ sha := ethcrypto.Sha3(enc)
+
+ cache.nodes[string(sha)] = NewNode(sha, value, true)
+ cache.IsDirty = true
+
+ return sha
+ }
+
+ return v
+}
+
+func (cache *Cache) Put(v interface{}) interface{} {
+ return cache.PutValue(v, false)
+}
+
+func (cache *Cache) Get(key []byte) *ethutil.Value {
+ // First check if the key is the cache
+ if cache.nodes[string(key)] != nil {
+ return cache.nodes[string(key)].Value
+ }
+
+ // Get the key of the database instead and cache it
+ data, _ := cache.db.Get(key)
+ // Create the cached value
+ value := ethutil.NewValueFromBytes(data)
+
+ defer func() {
+ if r := recover(); r != nil {
+ fmt.Println("RECOVER GET", cache, cache.nodes)
+ panic("bye")
+ }
+ }()
+ // Create caching node
+ cache.nodes[string(key)] = NewNode(key, value, false)
+
+ return value
+}
+
+func (cache *Cache) Delete(key []byte) {
+ delete(cache.nodes, string(key))
+
+ cache.db.Delete(key)
+}
+
+func (cache *Cache) Commit() {
+ // Don't try to commit if it isn't dirty
+ if !cache.IsDirty {
+ return
+ }
+
+ for key, node := range cache.nodes {
+ if node.Dirty {
+ cache.db.Put([]byte(key), node.Value.Encode())
+ node.Dirty = false
+ }
+ }
+ cache.IsDirty = false
+
+ // If the nodes grows beyond the 200 entries we simple empty it
+ // FIXME come up with something better
+ if len(cache.nodes) > 200 {
+ cache.nodes = make(map[string]*Node)
+ }
+}
+
+func (cache *Cache) Undo() {
+ for key, node := range cache.nodes {
+ if node.Dirty {
+ delete(cache.nodes, key)
+ }
+ }
+ cache.IsDirty = false
+}
+
+// A (modified) Radix Trie implementation. The Trie implements
+// a caching mechanism and will used cached values if they are
+// present. If a node is not present in the cache it will try to
+// fetch it from the database and store the cached value.
+// Please note that the data isn't persisted unless `Sync` is
+// explicitly called.
+type Trie struct {
+ mut sync.RWMutex
+ prevRoot interface{}
+ Root interface{}
+ //db Database
+ cache *Cache
+}
+
+func copyRoot(root interface{}) interface{} {
+ var prevRootCopy interface{}
+ if b, ok := root.([]byte); ok {
+ prevRootCopy = ethutil.CopyBytes(b)
+ } else {
+ prevRootCopy = root
+ }
+
+ return prevRootCopy
+}
+
+func New(db ethutil.Database, Root interface{}) *Trie {
+ // Make absolute sure the root is copied
+ r := copyRoot(Root)
+ p := copyRoot(Root)
+
+ return &Trie{cache: NewCache(db), Root: r, prevRoot: p}
+}
+
+/*
+ * Public (query) interface functions
+ */
+
+func (t *Trie) Update(key, value string) {
+ t.mut.Lock()
+ defer t.mut.Unlock()
+
+ k := CompactHexDecode(key)
+
+ root := t.UpdateState(t.Root, k, value)
+ switch root.(type) {
+ case string:
+ t.Root = root
+ case []byte:
+ t.Root = root
+ default:
+ t.Root = t.cache.PutValue(root, true)
+ }
+}
+
+func (t *Trie) Get(key string) string {
+ t.mut.Lock()
+ defer t.mut.Unlock()
+
+ k := CompactHexDecode(key)
+ c := ethutil.NewValue(t.getState(t.Root, k))
+
+ return c.Str()
+}
+
+func (t *Trie) Delete(key string) {
+ t.mut.Lock()
+ defer t.mut.Unlock()
+
+ k := CompactHexDecode(key)
+
+ root := t.deleteState(t.Root, k)
+ switch root.(type) {
+ case string:
+ t.Root = root
+ case []byte:
+ t.Root = root
+ default:
+ t.Root = t.cache.PutValue(root, true)
+ }
+}
+
+// Simple compare function which creates a rlp value out of the evaluated objects
+func (t *Trie) Cmp(trie *Trie) bool {
+ return ethutil.NewValue(t.Root).Cmp(ethutil.NewValue(trie.Root))
+}
+
+// Returns a copy of this trie
+func (t *Trie) Copy() *Trie {
+ trie := New(t.cache.db, t.Root)
+ for key, node := range t.cache.nodes {
+ trie.cache.nodes[key] = node.Copy()
+ }
+
+ return trie
+}
+
+// Save the cached value to the database.
+func (t *Trie) Sync() {
+ t.cache.Commit()
+ t.prevRoot = copyRoot(t.Root)
+}
+
+func (t *Trie) Undo() {
+ t.cache.Undo()
+ t.Root = t.prevRoot
+}
+
+func (t *Trie) Cache() *Cache {
+ return t.cache
+}
+
+func (t *Trie) getState(node interface{}, key []byte) interface{} {
+ n := ethutil.NewValue(node)
+ // Return the node if key is empty (= found)
+ if len(key) == 0 || n.IsNil() || n.Len() == 0 {
+ return node
+ }
+
+ currentNode := t.getNode(node)
+ length := currentNode.Len()
+
+ if length == 0 {
+ return ""
+ } else if length == 2 {
+ // Decode the key
+ k := CompactDecode(currentNode.Get(0).Str())
+ v := currentNode.Get(1).Raw()
+
+ if len(key) >= len(k) && bytes.Equal(k, key[:len(k)]) { //CompareIntSlice(k, key[:len(k)]) {
+ return t.getState(v, key[len(k):])
+ } else {
+ return ""
+ }
+ } else if length == 17 {
+ return t.getState(currentNode.Get(int(key[0])).Raw(), key[1:])
+ }
+
+ // It shouldn't come this far
+ panic("unexpected return")
+}
+
+func (t *Trie) getNode(node interface{}) *ethutil.Value {
+ n := ethutil.NewValue(node)
+
+ if !n.Get(0).IsNil() {
+ return n
+ }
+
+ str := n.Str()
+ if len(str) == 0 {
+ return n
+ } else if len(str) < 32 {
+ return ethutil.NewValueFromBytes([]byte(str))
+ }
+
+ data := t.cache.Get(n.Bytes())
+
+ return data
+}
+
+func (t *Trie) UpdateState(node interface{}, key []byte, value string) interface{} {
+ return t.InsertState(node, key, value)
+}
+
+func (t *Trie) Put(node interface{}) interface{} {
+ return t.cache.Put(node)
+
+}
+
+func EmptyStringSlice(l int) []interface{} {
+ slice := make([]interface{}, l)
+ for i := 0; i < l; i++ {
+ slice[i] = ""
+ }
+ return slice
+}
+
+func (t *Trie) InsertState(node interface{}, key []byte, value interface{}) interface{} {
+ if len(key) == 0 {
+ return value
+ }
+
+ // New node
+ n := ethutil.NewValue(node)
+ if node == nil || n.Len() == 0 {
+ newNode := []interface{}{CompactEncode(key), value}
+
+ return t.Put(newNode)
+ }
+
+ currentNode := t.getNode(node)
+ // Check for "special" 2 slice type node
+ if currentNode.Len() == 2 {
+ // Decode the key
+
+ k := CompactDecode(currentNode.Get(0).Str())
+ v := currentNode.Get(1).Raw()
+
+ // Matching key pair (ie. there's already an object with this key)
+ if bytes.Equal(k, key) { //CompareIntSlice(k, key) {
+ newNode := []interface{}{CompactEncode(key), value}
+ return t.Put(newNode)
+ }
+
+ var newHash interface{}
+ matchingLength := MatchingNibbleLength(key, k)
+ if matchingLength == len(k) {
+ // Insert the hash, creating a new node
+ newHash = t.InsertState(v, key[matchingLength:], value)
+ } else {
+ // Expand the 2 length slice to a 17 length slice
+ oldNode := t.InsertState("", k[matchingLength+1:], v)
+ newNode := t.InsertState("", key[matchingLength+1:], value)
+ // Create an expanded slice
+ scaledSlice := EmptyStringSlice(17)
+ // Set the copied and new node
+ scaledSlice[k[matchingLength]] = oldNode
+ scaledSlice[key[matchingLength]] = newNode
+
+ newHash = t.Put(scaledSlice)
+ }
+
+ if matchingLength == 0 {
+ // End of the chain, return
+ return newHash
+ } else {
+ newNode := []interface{}{CompactEncode(key[:matchingLength]), newHash}
+ return t.Put(newNode)
+ }
+ } else {
+
+ // Copy the current node over to the new node and replace the first nibble in the key
+ newNode := EmptyStringSlice(17)
+
+ for i := 0; i < 17; i++ {
+ cpy := currentNode.Get(i).Raw()
+ if cpy != nil {
+ newNode[i] = cpy
+ }
+ }
+
+ newNode[key[0]] = t.InsertState(currentNode.Get(int(key[0])).Raw(), key[1:], value)
+
+ return t.Put(newNode)
+ }
+
+ panic("unexpected end")
+}
+
+func (t *Trie) deleteState(node interface{}, key []byte) interface{} {
+ if len(key) == 0 {
+ return ""
+ }
+
+ // New node
+ n := ethutil.NewValue(node)
+ //if node == nil || (n.Type() == reflect.String && (n.Str() == "" || n.Get(0).IsNil())) || n.Len() == 0 {
+ if node == nil || n.Len() == 0 {
+ //return nil
+ //fmt.Printf("<empty ret> %x %d\n", n, len(n.Bytes()))
+
+ return ""
+ }
+
+ currentNode := t.getNode(node)
+ // Check for "special" 2 slice type node
+ if currentNode.Len() == 2 {
+ // Decode the key
+ k := CompactDecode(currentNode.Get(0).Str())
+ v := currentNode.Get(1).Raw()
+
+ // Matching key pair (ie. there's already an object with this key)
+ if bytes.Equal(k, key) { //CompareIntSlice(k, key) {
+ //fmt.Printf("<delete ret> %x\n", v)
+
+ return ""
+ } else if bytes.Equal(key[:len(k)], k) { //CompareIntSlice(key[:len(k)], k) {
+ hash := t.deleteState(v, key[len(k):])
+ child := t.getNode(hash)
+
+ var newNode []interface{}
+ if child.Len() == 2 {
+ newKey := append(k, CompactDecode(child.Get(0).Str())...)
+ newNode = []interface{}{CompactEncode(newKey), child.Get(1).Raw()}
+ } else {
+ newNode = []interface{}{currentNode.Get(0).Str(), hash}
+ }
+
+ //fmt.Printf("%x\n", newNode)
+
+ return t.Put(newNode)
+ } else {
+ return node
+ }
+ } else {
+ // Copy the current node over to the new node and replace the first nibble in the key
+ n := EmptyStringSlice(17)
+ var newNode []interface{}
+
+ for i := 0; i < 17; i++ {
+ cpy := currentNode.Get(i).Raw()
+ if cpy != nil {
+ n[i] = cpy
+ }
+ }
+
+ n[key[0]] = t.deleteState(n[key[0]], key[1:])
+ amount := -1
+ for i := 0; i < 17; i++ {
+ if n[i] != "" {
+ if amount == -1 {
+ amount = i
+ } else {
+ amount = -2
+ }
+ }
+ }
+ if amount == 16 {
+ newNode = []interface{}{CompactEncode([]byte{16}), n[amount]}
+ } else if amount >= 0 {
+ child := t.getNode(n[amount])
+ if child.Len() == 17 {
+ newNode = []interface{}{CompactEncode([]byte{byte(amount)}), n[amount]}
+ } else if child.Len() == 2 {
+ key := append([]byte{byte(amount)}, CompactDecode(child.Get(0).Str())...)
+ newNode = []interface{}{CompactEncode(key), child.Get(1).Str()}
+ }
+
+ } else {
+ newNode = n
+ }
+
+ //fmt.Printf("%x\n", newNode)
+ return t.Put(newNode)
+ }
+
+ panic("unexpected return")
+}
+
+type TrieIterator struct {
+ trie *Trie
+ key string
+ value string
+
+ shas [][]byte
+ values []string
+
+ lastNode []byte
+}
+
+func (t *Trie) NewIterator() *TrieIterator {
+ return &TrieIterator{trie: t}
+}
+
+func (self *Trie) Iterator() *Iterator {
+ return NewIterator(self)
+}
+
+// Some time in the near future this will need refactoring :-)
+// XXX Note to self, IsSlice == inline node. Str == sha3 to node
+func (it *TrieIterator) workNode(currentNode *ethutil.Value) {
+ if currentNode.Len() == 2 {
+ k := CompactDecode(currentNode.Get(0).Str())
+
+ if currentNode.Get(1).Str() == "" {
+ it.workNode(currentNode.Get(1))
+ } else {
+ if k[len(k)-1] == 16 {
+ it.values = append(it.values, currentNode.Get(1).Str())
+ } else {
+ it.shas = append(it.shas, currentNode.Get(1).Bytes())
+ it.getNode(currentNode.Get(1).Bytes())
+ }
+ }
+ } else {
+ for i := 0; i < currentNode.Len(); i++ {
+ if i == 16 && currentNode.Get(i).Len() != 0 {
+ it.values = append(it.values, currentNode.Get(i).Str())
+ } else {
+ if currentNode.Get(i).Str() == "" {
+ it.workNode(currentNode.Get(i))
+ } else {
+ val := currentNode.Get(i).Str()
+ if val != "" {
+ it.shas = append(it.shas, currentNode.Get(1).Bytes())
+ it.getNode([]byte(val))
+ }
+ }
+ }
+ }
+ }
+}
+
+func (it *TrieIterator) getNode(node []byte) {
+ currentNode := it.trie.cache.Get(node)
+ it.workNode(currentNode)
+}
+
+func (it *TrieIterator) Collect() [][]byte {
+ if it.trie.Root == "" {
+ return nil
+ }
+
+ it.getNode(ethutil.NewValue(it.trie.Root).Bytes())
+
+ return it.shas
+}
+
+func (it *TrieIterator) Purge() int {
+ shas := it.Collect()
+ for _, sha := range shas {
+ it.trie.cache.Delete(sha)
+ }
+ return len(it.values)
+}
+
+func (it *TrieIterator) Key() string {
+ return ""
+}
+
+func (it *TrieIterator) Value() string {
+ return ""
+}
+
+type EachCallback func(key string, node *ethutil.Value)
+
+func (it *TrieIterator) Each(cb EachCallback) {
+ it.fetchNode(nil, ethutil.NewValue(it.trie.Root).Bytes(), cb)
+}
+
+func (it *TrieIterator) fetchNode(key []byte, node []byte, cb EachCallback) {
+ it.iterateNode(key, it.trie.cache.Get(node), cb)
+}
+
+func (it *TrieIterator) iterateNode(key []byte, currentNode *ethutil.Value, cb EachCallback) {
+ if currentNode.Len() == 2 {
+ k := CompactDecode(currentNode.Get(0).Str())
+
+ pk := append(key, k...)
+ if currentNode.Get(1).Len() != 0 && currentNode.Get(1).Str() == "" {
+ it.iterateNode(pk, currentNode.Get(1), cb)
+ } else {
+ if k[len(k)-1] == 16 {
+ cb(DecodeCompact(pk), currentNode.Get(1))
+ } else {
+ it.fetchNode(pk, currentNode.Get(1).Bytes(), cb)
+ }
+ }
+ } else {
+ for i := 0; i < currentNode.Len(); i++ {
+ pk := append(key, byte(i))
+ if i == 16 && currentNode.Get(i).Len() != 0 {
+ cb(DecodeCompact(pk), currentNode.Get(i))
+ } else {
+ if currentNode.Get(i).Len() != 0 && currentNode.Get(i).Str() == "" {
+ it.iterateNode(pk, currentNode.Get(i), cb)
+ } else {
+ val := currentNode.Get(i).Str()
+ if val != "" {
+ it.fetchNode(pk, []byte(val), cb)
+ }
+ }
+ }
+ }
+ }
+}