65 lines
1.4 KiB
Go
65 lines
1.4 KiB
Go
package trie
|
|
|
|
import (
|
|
"github.com/ethereum/go-ethereum/compression/rle"
|
|
"github.com/ethereum/go-ethereum/ethdb"
|
|
"github.com/ethereum/go-ethereum/logger/glog"
|
|
"github.com/syndtr/goleveldb/leveldb"
|
|
)
|
|
|
|
type Backend interface {
|
|
Get([]byte) ([]byte, error)
|
|
Put([]byte, []byte) error
|
|
}
|
|
|
|
type Cache struct {
|
|
batch *leveldb.Batch
|
|
store map[string][]byte
|
|
backend Backend
|
|
}
|
|
|
|
func NewCache(backend Backend) *Cache {
|
|
return &Cache{new(leveldb.Batch), make(map[string][]byte), backend}
|
|
}
|
|
|
|
func (self *Cache) Get(key []byte) []byte {
|
|
data := self.store[string(key)]
|
|
if data == nil {
|
|
data, _ = self.backend.Get(key)
|
|
}
|
|
|
|
return data
|
|
}
|
|
|
|
func (self *Cache) Put(key []byte, data []byte) {
|
|
// write the data to the ldb batch
|
|
self.batch.Put(key, rle.Compress(data))
|
|
self.store[string(key)] = data
|
|
}
|
|
|
|
// Flush flushes the trie to the backing layer. If this is a leveldb instance
|
|
// we'll use a batched write, otherwise we'll use regular put.
|
|
func (self *Cache) Flush() {
|
|
if db, ok := self.backend.(*ethdb.LDBDatabase); ok {
|
|
if err := db.LDB().Write(self.batch, nil); err != nil {
|
|
glog.Fatal("db write err:", err)
|
|
}
|
|
} else {
|
|
for k, v := range self.store {
|
|
self.backend.Put([]byte(k), v)
|
|
}
|
|
}
|
|
}
|
|
|
|
func (self *Cache) Copy() *Cache {
|
|
cache := NewCache(self.backend)
|
|
for k, v := range self.store {
|
|
cache.store[k] = v
|
|
}
|
|
return cache
|
|
}
|
|
|
|
func (self *Cache) Reset() {
|
|
//self.store = make(map[string][]byte)
|
|
}
|