Added a few more comments and cleaned up code

This commit is contained in:
obscuren 2014-01-01 14:06:00 +01:00
parent df6f7e8a0e
commit 30f3b4d4e4

111
trie.go
View File

@ -10,6 +10,38 @@ type Database interface {
Get(key []byte) ([]byte, error)
}
/*
* Trie helper functions
*/
// Helper function for printing out the raw contents of a slice
func PrintSlice(slice []string) {
fmt.Printf("[")
for i, val := range slice {
fmt.Printf("%q", val)
if i != len(slice)-1 { fmt.Printf(",") }
}
fmt.Printf("]\n")
}
// RLP Decodes a node in to a [2] or [17] string slice
func DecodeNode(data []byte) []string {
dec, _ := Decode(data, 0)
if slice, ok := dec.([]interface{}); ok {
strSlice := make([]string, len(slice))
for i, s := range slice {
if str, ok := s.([]byte); ok {
strSlice[i] = string(str)
}
}
return strSlice
}
return nil
}
// A (modified) Radix Trie implementation
type Trie struct {
root string
db Database
@ -19,18 +51,9 @@ func NewTrie(db Database, root string) *Trie {
return &Trie{db: db, root: ""}
}
func (t *Trie) Put(node interface{}) []byte {
//if s, ok := node.([]string); ok {
// PrintSlice(s)
//}
enc := Encode(node)
sha := Sha256Bin(enc)
t.db.Put([]byte(sha), enc)
return sha
}
/*
* Public (query) interface functions
*/
func (t *Trie) Update(key string, value string) {
k := CompactHexDecode(key)
@ -43,10 +66,29 @@ func (t *Trie) Get(key string) string {
return t.GetState(t.root, k)
}
/*
* State functions (shouldn't be needed directly).
*/
// Wrapper around the regular db "Put" which generates a key and value
func (t *Trie) Put(node interface{}) []byte {
enc := Encode(node)
sha := Sha256Bin(enc)
t.db.Put([]byte(sha), enc)
return sha
}
// Helper function for printing a node (using fetch, decode and slice printing)
func (t *Trie) PrintNode(n string) {
data, _ := t.db.Get([]byte(n))
d := DecodeNode(data)
PrintSlice(d)
}
// Returns the state of an object
func (t *Trie) GetState(node string, key []int) string {
//if Debug { fmt.Println("get =", key) }
// Return the node if key is empty (= found)
if len(key) == 0 || node == "" {
return node
@ -66,10 +108,6 @@ func (t *Trie) GetState(node string, key []int) string {
k := CompactDecode(currentNode[0])
v := currentNode[1]
//fmt.Println(k, key)
//fmt.Printf("k1:%v\nk2:%v\n", k, key[:len(k)-1])
//fmt.Println(len(key), ">=", len(k)-1, "&&", k, key[:len(k)])
if len(key) >= len(k) && CompareIntSlice(k, key[:len(k)]) {
return t.GetState(v, key[len(k):])
} else {
@ -95,47 +133,13 @@ func (t *Trie) UpdateState(node string, key []int, value string) string {
return ""
}
func DecodeNode(data []byte) []string {
dec, _ := Decode(data, 0)
if slice, ok := dec.([]interface{}); ok {
strSlice := make([]string, len(slice))
for i, s := range slice {
if str, ok := s.([]byte); ok {
strSlice[i] = string(str)
}
}
return strSlice
}
return nil
}
func (t *Trie) PrintNode(n string) {
data, _ := t.db.Get([]byte(n))
d := DecodeNode(data)
PrintSlice(d)
}
func PrintSlice(slice []string) {
fmt.Printf("[")
for i, val := range slice {
fmt.Printf("%q", val)
if i != len(slice)-1 { fmt.Printf(",") }
}
fmt.Printf("]\n")
}
func (t *Trie) InsertState(node string, key []int, value string) string {
//if Debug { fmt.Println("insrt", key, value, "node:", node) }
if len(key) == 0 {
return value
}
//fmt.Println(node)
// Root node!
// New node
if node == "" {
newNode := []string{ CompactEncode(key), value }
@ -195,4 +199,3 @@ func (t *Trie) InsertState(node string, key []int, value string) string {
return ""
}