55 lines
1.0 KiB
Go
55 lines
1.0 KiB
Go
package trie
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import "github.com/ethereum/go-ethereum/logger/glog"
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type Backend interface {
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Get([]byte) ([]byte, error)
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Put([]byte, []byte) error
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}
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type Cache struct {
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store map[string][]byte
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backend Backend
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}
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func NewCache(backend Backend) *Cache {
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return &Cache{make(map[string][]byte), backend}
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}
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func (self *Cache) Get(key []byte) []byte {
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data := self.store[string(key)]
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if data == nil {
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data, _ = self.backend.Get(key)
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}
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return data
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}
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func (self *Cache) Put(key []byte, data []byte) {
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self.store[string(key)] = data
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}
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func (self *Cache) Flush() {
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for k, v := range self.store {
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if err := self.backend.Put([]byte(k), v); err != nil {
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glog.Fatal("db write err:", err)
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}
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}
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// This will eventually grow too large. We'd could
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// do a make limit on storage and push out not-so-popular nodes.
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//self.Reset()
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}
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func (self *Cache) Copy() *Cache {
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cache := NewCache(self.backend)
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for k, v := range self.store {
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cache.store[k] = v
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}
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return cache
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}
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func (self *Cache) Reset() {
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//self.store = make(map[string][]byte)
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}
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