dbSyncIterator

bzz/dbstore.go

@@ -13,6 +13,7 @@ import (
 
  "github.com/ethereum/go-ethereum/rlp"
  "github.com/syndtr/goleveldb/leveldb"
+ "github.com/syndtr/goleveldb/leveldb/iterator"
 )
 
 const gcArraySize = 10000
@@ -75,11 +76,7 @@ func getIndexKey(hash Key) []byte {
  HashSize := len(hash)
  key := make([]byte, HashSize+1)
  key[0] = 0
- // db keys derived from hash:
- // two halves swapped for uniformly distributed prefix
- copy(key[1:HashSize/2+1], hash[HashSize/2:HashSize])
- copy(key[HashSize/2+1:HashSize+1], hash[0:HashSize/2])
-
+ copy(key[1:], hash[:])
  return key
 }
 
@@ -188,6 +185,7 @@ func (s *dbStore) collectGarbage(ratio float32) {
  s.gcPos = nil
  }
  }
+ it.Release()
 
  cutidx := gcListSelect(s.gcArray, 0, gcnt-1, int(float32(gcnt)*ratio))
  cutval := s.gcArray[cutidx].value
@@ -375,3 +373,39 @@ func newDbStore(path string) (s *dbStore, err error) {
 func (s *dbStore) close() {
  s.db.Close()
 }
+
+type dbSyncIterator struct {
+ it iterator.Iterator
+ stop Key
+ scFrom, scTo uint64
+}
+
+func (s *dbStore) newDbSyncIterator(start Key, stop Key, scFrom uint64, scTo uint64) (si *dbSyncIterator) {
+ si.it = s.db.NewIterator()
+ si.it.Seek(getIndexKey(start))
+ si.stop = stop
+ si.scFrom = scFrom
+ si.scTo = scTo
+ return
+}
+
+func (si *dbSyncIterator) next() (hash Key) {
+ for si.it.Valid() {
+ key := si.it.Key()
+ if key[0] != 0 {
+ break
+ }
+ hash = key[1:]
+ if bytes.Compare(hash, si.stop) > 0 {
+ break
+ }
+ var index dpaDBIndex
+ decodeIndex(si.it.Value(), &index)
+ si.it.Next()
+ if (index.Idx >= si.scFrom) && (index.Idx <= si.scTo) {
+ return
+ }
+ }
+ si.it.Release()
+ return nil
+}