Fixed iterator bug which skips the 0x000...000 key

This commit is contained in:
= 2015-03-05 01:42:32 +00:00
parent a56243075a
commit a6fe92194f

View File

@ -1,6 +1,8 @@
package trie
import "bytes"
import (
"bytes"
)
type Iterator struct {
trie *Trie
@ -10,22 +12,28 @@ type Iterator struct {
}
func NewIterator(trie *Trie) *Iterator {
return &Iterator{trie: trie, Key: make([]byte, 32)}
return &Iterator{trie: trie, Key: nil}
}
func (self *Iterator) Next() bool {
self.trie.mu.Lock()
defer self.trie.mu.Unlock()
isIterStart := false
if self.Key == nil {
isIterStart = true
self.Key = make([]byte, 32)
}
key := RemTerm(CompactHexDecode(string(self.Key)))
k := self.next(self.trie.root, key)
k := self.next(self.trie.root, key, isIterStart)
self.Key = []byte(DecodeCompact(k))
return len(k) > 0
}
func (self *Iterator) next(node Node, key []byte) []byte {
func (self *Iterator) next(node Node, key []byte, isIterStart bool) []byte {
if node == nil {
return nil
}
@ -33,7 +41,7 @@ func (self *Iterator) next(node Node, key []byte) []byte {
switch node := node.(type) {
case *FullNode:
if len(key) > 0 {
k := self.next(node.branch(key[0]), key[1:])
k := self.next(node.branch(key[0]), key[1:], isIterStart)
if k != nil {
return append([]byte{key[0]}, k...)
}
@ -54,7 +62,13 @@ func (self *Iterator) next(node Node, key []byte) []byte {
case *ShortNode:
k := RemTerm(node.Key())
if vnode, ok := node.Value().(*ValueNode); ok {
if bytes.Compare([]byte(k), key) > 0 {
switch bytes.Compare([]byte(k), key) {
case 0:
if isIterStart {
self.Value = vnode.Val()
return k
}
case 1:
self.Value = vnode.Val()
return k
}
@ -64,7 +78,7 @@ func (self *Iterator) next(node Node, key []byte) []byte {
var ret []byte
skey := key[len(k):]
if BeginsWith(key, k) {
ret = self.next(cnode, skey)
ret = self.next(cnode, skey, isIterStart)
} else if bytes.Compare(k, key[:len(k)]) > 0 {
return self.key(node)
}