go-ethereum/ptrie/cache.go
2014-11-19 16:56:01 +01:00

43 lines
790 B
Go

package ptrie
type Backend interface {
Get([]byte) ([]byte, error)
Put([]byte, []byte)
}
type Cache struct {
store map[string][]byte
backend Backend
}
func NewCache(backend Backend) *Cache {
return &Cache{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) {
self.store[string(key)] = data
}
func (self *Cache) Flush() {
for k, v := range self.store {
self.backend.Put([]byte(k), v)
}
// This will eventually grow too large. We'd could
// do a make limit on storage and push out not-so-popular nodes.
//self.Reset()
}
func (self *Cache) Reset() {
self.store = make(map[string][]byte)
}