go-ethereum/ethdb/memory_database.go

147 lines
3.0 KiB
Go

// Copyright 2014 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package ethdb
import (
"errors"
"fmt"
"sync"
"github.com/ethereum/go-ethereum/common"
)
/*
* This is a test memory database. Do not use for any production it does not get persisted
*/
type MemDatabase struct {
db map[string][]byte
lock sync.RWMutex
}
func NewMemDatabase() (*MemDatabase, error) {
return &MemDatabase{
db: make(map[string][]byte),
}, nil
}
func (db *MemDatabase) Put(key []byte, value []byte) error {
db.lock.Lock()
defer db.lock.Unlock()
db.db[string(key)] = common.CopyBytes(value)
return nil
}
func (db *MemDatabase) Set(key []byte, value []byte) {
db.lock.Lock()
defer db.lock.Unlock()
db.Put(key, value)
}
func (db *MemDatabase) Get(key []byte) ([]byte, error) {
db.lock.RLock()
defer db.lock.RUnlock()
if entry, ok := db.db[string(key)]; ok {
return entry, nil
}
return nil, errors.New("not found")
}
func (db *MemDatabase) Keys() [][]byte {
db.lock.RLock()
defer db.lock.RUnlock()
keys := [][]byte{}
for key, _ := range db.db {
keys = append(keys, []byte(key))
}
return keys
}
/*
func (db *MemDatabase) GetKeys() []*common.Key {
data, _ := db.Get([]byte("KeyRing"))
return []*common.Key{common.NewKeyFromBytes(data)}
}
*/
func (db *MemDatabase) Delete(key []byte) error {
db.lock.Lock()
defer db.lock.Unlock()
delete(db.db, string(key))
return nil
}
func (db *MemDatabase) Print() {
db.lock.RLock()
defer db.lock.RUnlock()
for key, val := range db.db {
fmt.Printf("%x(%d): ", key, len(key))
node := common.NewValueFromBytes(val)
fmt.Printf("%q\n", node.Val)
}
}
func (db *MemDatabase) Close() {
}
func (db *MemDatabase) LastKnownTD() []byte {
data, _ := db.Get([]byte("LastKnownTotalDifficulty"))
if len(data) == 0 || data == nil {
data = []byte{0x0}
}
return data
}
func (db *MemDatabase) NewBatch() Batch {
return &memBatch{db: db}
}
type kv struct{ k, v []byte }
type memBatch struct {
db *MemDatabase
writes []kv
lock sync.RWMutex
}
func (b *memBatch) Put(key, value []byte) error {
b.lock.Lock()
defer b.lock.Unlock()
b.writes = append(b.writes, kv{key, common.CopyBytes(value)})
return nil
}
func (b *memBatch) Write() error {
b.lock.RLock()
defer b.lock.RUnlock()
b.db.lock.Lock()
defer b.db.lock.Unlock()
for _, kv := range b.writes {
b.db.db[string(kv.k)] = kv.v
}
return nil
}