forked from cerc-io/plugeth
132 lines
2.9 KiB
Go
132 lines
2.9 KiB
Go
package ethdb
|
|
|
|
import (
|
|
"sync"
|
|
|
|
"github.com/ethereum/go-ethereum/compression/rle"
|
|
"github.com/ethereum/go-ethereum/logger"
|
|
"github.com/ethereum/go-ethereum/logger/glog"
|
|
"github.com/syndtr/goleveldb/leveldb"
|
|
"github.com/syndtr/goleveldb/leveldb/errors"
|
|
"github.com/syndtr/goleveldb/leveldb/iterator"
|
|
"github.com/syndtr/goleveldb/leveldb/opt"
|
|
)
|
|
|
|
var OpenFileLimit = 64
|
|
|
|
type LDBDatabase struct {
|
|
fn string
|
|
|
|
mu sync.Mutex
|
|
db *leveldb.DB
|
|
|
|
queue map[string][]byte
|
|
|
|
quit chan struct{}
|
|
}
|
|
|
|
// NewLDBDatabase returns a LevelDB wrapped object. LDBDatabase does not persist data by
|
|
// it self but requires a background poller which syncs every X. `Flush` should be called
|
|
// when data needs to be stored and written to disk.
|
|
func NewLDBDatabase(file string) (*LDBDatabase, error) {
|
|
// Open the db
|
|
db, err := leveldb.OpenFile(file, &opt.Options{OpenFilesCacheCapacity: OpenFileLimit})
|
|
// check for curruption and attempt to recover
|
|
if _, iscorrupted := err.(*errors.ErrCorrupted); iscorrupted {
|
|
db, err = leveldb.RecoverFile(file, nil)
|
|
}
|
|
// (re) check for errors and abort if opening of the db failed
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
database := &LDBDatabase{
|
|
fn: file,
|
|
db: db,
|
|
quit: make(chan struct{}),
|
|
}
|
|
database.makeQueue()
|
|
|
|
return database, nil
|
|
}
|
|
|
|
func (self *LDBDatabase) makeQueue() {
|
|
self.queue = make(map[string][]byte)
|
|
}
|
|
|
|
// Put puts the given key / value to the queue
|
|
func (self *LDBDatabase) Put(key []byte, value []byte) {
|
|
self.mu.Lock()
|
|
defer self.mu.Unlock()
|
|
|
|
self.queue[string(key)] = value
|
|
}
|
|
|
|
// Get returns the given key if it's present.
|
|
func (self *LDBDatabase) Get(key []byte) ([]byte, error) {
|
|
self.mu.Lock()
|
|
defer self.mu.Unlock()
|
|
|
|
// Check queue first
|
|
if dat, ok := self.queue[string(key)]; ok {
|
|
return dat, nil
|
|
}
|
|
|
|
dat, err := self.db.Get(key, nil)
|
|
if err != nil {
|
|
return nil, err
|
|
}
|
|
|
|
return rle.Decompress(dat)
|
|
}
|
|
|
|
// Delete deletes the key from the queue and database
|
|
func (self *LDBDatabase) Delete(key []byte) error {
|
|
self.mu.Lock()
|
|
defer self.mu.Unlock()
|
|
|
|
// make sure it's not in the queue
|
|
delete(self.queue, string(key))
|
|
|
|
return self.db.Delete(key, nil)
|
|
}
|
|
|
|
func (self *LDBDatabase) LastKnownTD() []byte {
|
|
data, _ := self.Get([]byte("LTD"))
|
|
|
|
if len(data) == 0 {
|
|
data = []byte{0x0}
|
|
}
|
|
|
|
return data
|
|
}
|
|
|
|
func (self *LDBDatabase) NewIterator() iterator.Iterator {
|
|
return self.db.NewIterator(nil, nil)
|
|
}
|
|
|
|
// Flush flushes out the queue to leveldb
|
|
func (self *LDBDatabase) Flush() error {
|
|
self.mu.Lock()
|
|
defer self.mu.Unlock()
|
|
|
|
batch := new(leveldb.Batch)
|
|
|
|
for key, value := range self.queue {
|
|
batch.Put([]byte(key), rle.Compress(value))
|
|
}
|
|
self.makeQueue() // reset the queue
|
|
|
|
glog.V(logger.Detail).Infoln("Flush database: ", self.fn)
|
|
|
|
return self.db.Write(batch, nil)
|
|
}
|
|
|
|
func (self *LDBDatabase) Close() {
|
|
if err := self.Flush(); err != nil {
|
|
glog.V(logger.Error).Infof("error: flush '%s': %v\n", self.fn, err)
|
|
}
|
|
|
|
self.db.Close()
|
|
glog.V(logger.Error).Infoln("flushed and closed db:", self.fn)
|
|
}
|