github.com/xfond/eth-implementation@v1.8.9-0.20180514135602-f6bc65fc6811/swarm/storage/database.go (about) 1 // Copyright 2016 The go-ethereum Authors 2 // This file is part of the go-ethereum library. 3 // 4 // The go-ethereum library is free software: you can redistribute it and/or modify 5 // it under the terms of the GNU Lesser General Public License as published by 6 // the Free Software Foundation, either version 3 of the License, or 7 // (at your option) any later version. 8 // 9 // The go-ethereum library is distributed in the hope that it will be useful, 10 // but WITHOUT ANY WARRANTY; without even the implied warranty of 11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 // GNU Lesser General Public License for more details. 13 // 14 // You should have received a copy of the GNU Lesser General Public License 15 // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>. 16 17 package storage 18 19 // this is a clone of an earlier state of the ethereum ethdb/database 20 // no need for queueing/caching 21 22 import ( 23 "fmt" 24 25 "github.com/syndtr/goleveldb/leveldb" 26 "github.com/syndtr/goleveldb/leveldb/iterator" 27 "github.com/syndtr/goleveldb/leveldb/opt" 28 ) 29 30 const openFileLimit = 128 31 32 type LDBDatabase struct { 33 db *leveldb.DB 34 } 35 36 func NewLDBDatabase(file string) (*LDBDatabase, error) { 37 // Open the db 38 db, err := leveldb.OpenFile(file, &opt.Options{OpenFilesCacheCapacity: openFileLimit}) 39 if err != nil { 40 return nil, err 41 } 42 43 database := &LDBDatabase{db: db} 44 45 return database, nil 46 } 47 48 func (self *LDBDatabase) Put(key []byte, value []byte) { 49 err := self.db.Put(key, value, nil) 50 if err != nil { 51 fmt.Println("Error put", err) 52 } 53 } 54 55 func (self *LDBDatabase) Get(key []byte) ([]byte, error) { 56 dat, err := self.db.Get(key, nil) 57 if err != nil { 58 return nil, err 59 } 60 return dat, nil 61 } 62 63 func (self *LDBDatabase) Delete(key []byte) error { 64 return self.db.Delete(key, nil) 65 } 66 67 func (self *LDBDatabase) LastKnownTD() []byte { 68 data, _ := self.Get([]byte("LTD")) 69 70 if len(data) == 0 { 71 data = []byte{0x0} 72 } 73 74 return data 75 } 76 77 func (self *LDBDatabase) NewIterator() iterator.Iterator { 78 return self.db.NewIterator(nil, nil) 79 } 80 81 func (self *LDBDatabase) Write(batch *leveldb.Batch) error { 82 return self.db.Write(batch, nil) 83 } 84 85 func (self *LDBDatabase) Close() { 86 // Close the leveldb database 87 self.db.Close() 88 }