func (i *iterator) Next() bool {
i.d.DB.View(func(tx *bolt.Tx) error {
b := tx.Bucket(bucketName)
c := b.Cursor()
var key []byte
var value []byte
if !i.seeked {
i.seeked = true
if i.key == nil {
key, value = c.First()
} else {
key, value = c.Seek(i.key)
}
} else {
c.Seek(i.key)
key, value = c.Next()
}
i.key = bytes.CloneBytes(key)
i.value = bytes.CloneBytes(value)
return nil
})
return i.key != nil
}
func (d *db) SeekReverse(startKey []byte) ([]byte, []byte, error) {
var key, value []byte
err := d.DB.View(func(tx *bolt.Tx) error {
b := tx.Bucket(bucketName)
c := b.Cursor()
var k, v []byte
if startKey == nil {
k, v = c.Last()
} else {
c.Seek(startKey)
k, v = c.Prev()
}
if k != nil {
key, value = bytes.CloneBytes(k), bytes.CloneBytes(v)
}
return nil
})
if err != nil {
return nil, nil, errors.Trace(err)
}
if key == nil {
return nil, nil, errors.Trace(engine.ErrNotFound)
}
return key, value, nil
}
func (d *db) MultiSeek(keys [][]byte) []*engine.MSeekResult {
res := make([]*engine.MSeekResult, 0, len(keys))
d.DB.View(func(tx *bolt.Tx) error {
b := tx.Bucket(bucketName)
c := b.Cursor()
for _, key := range keys {
var k, v []byte
if key == nil {
k, v = c.First()
} else {
k, v = c.Seek(key)
}
r := &engine.MSeekResult{}
if k == nil {
r.Err = engine.ErrNotFound
} else {
r.Key, r.Value, r.Err = bytes.CloneBytes(k), bytes.CloneBytes(v), nil
}
res = append(res, r)
}
return nil
})
return res
}
func (i *iterator) Seek(startKey []byte) bool {
i.d.DB.View(func(tx *bolt.Tx) error {
b := tx.Bucket(bucketName)
c := b.Cursor()
var key []byte
var value []byte
key, value = c.Seek(startKey)
i.key = bytes.CloneBytes(key)
i.value = bytes.CloneBytes(value)
return nil
})
return i.key != nil
}
func (it *dbIter) Next() (kv.Iterator, error) {
encKey := codec.EncodeBytes(nil, it.startKey)
var retErr error
var engineIter engine.Iterator
for {
var err error
engineIter, err = it.s.internalSeek(encKey)
if err != nil {
it.valid = false
retErr = err
break
}
metaKey := engineIter.Key()
// Get real key from metaKey
key, _, err := MvccDecode(metaKey)
if err != nil {
// It's not a valid metaKey, maybe overflow (other data).
it.valid = false
break
}
// Get kv pair.
val, err := it.s.MvccGet(key, it.exceptedVersion)
if err != nil && !errors2.ErrorEqual(err, kv.ErrNotExist) {
// Get this version error
it.valid = false
retErr = err
break
}
if val != nil {
it.k = bytes.CloneBytes(key)
it.v = bytes.CloneBytes(val)
it.startKey = key.Next()
break
}
// Current key's all versions are deleted, just go next key.
encKey = codec.EncodeBytes(nil, key.Next())
}
return it, errors.Trace(retErr)
}
func (d *db) Get(key []byte) ([]byte, error) {
var value []byte
err := d.DB.View(func(tx *bolt.Tx) error {
b := tx.Bucket(bucketName)
v := b.Get(key)
if v == nil {
return errors.Trace(engine.ErrNotFound)
}
value = bytes.CloneBytes(v)
return nil
})
return value, errors.Trace(err)
}
func (gc *localstoreCompactor) getAllVersions(k kv.Key) ([]kv.EncodedKey, error) {
startKey := MvccEncodeVersionKey(k, kv.MaxVersion)
endKey := MvccEncodeVersionKey(k, kv.MinVersion)
it, err := gc.db.Seek(startKey)
if err != nil {
return nil, errors.Trace(err)
}
defer it.Release()
var ret []kv.EncodedKey
for it.Next() {
if kv.EncodedKey(it.Key()).Cmp(endKey) < 0 {
ret = append(ret, bytes.CloneBytes(kv.EncodedKey(it.Key())))
}
}
return ret, nil
}
func (gc *localstoreCompactor) getAllVersions(key kv.Key) ([]kv.EncodedKey, error) {
var keys []kv.EncodedKey
k := key
for ver := kv.MaxVersion; ver.Ver > 0; ver.Ver-- {
mvccK, _, err := gc.db.Seek(MvccEncodeVersionKey(key, ver))
if terror.ErrorEqual(err, engine.ErrNotFound) {
break
}
if err != nil {
return nil, errors.Trace(err)
}
k, ver, err = MvccDecode(mvccK)
if k.Cmp(key) != 0 {
break
}
if err != nil {
return nil, errors.Trace(err)
}
keys = append(keys, bytes.CloneBytes(mvccK))
}
return keys, nil
}
func (s *dbSnapshot) MvccGet(k kv.Key, ver kv.Version) ([]byte, error) {
// engine Snapshot return nil, nil for value not found,
// so here we will check nil and return kv.ErrNotExist.
// get newest version, (0, MaxUint64)
// Key arrangement:
// Key -> META
// ...
// Key_ver
// Key_ver-1
// Key_ver-2
// ...
// Key_ver-n
// Key_0
// NextKey -> META
// NextKey_xxx
startKey := MvccEncodeVersionKey(k, ver)
endKey := MvccEncodeVersionKey(k, kv.MinVersion)
it, err := s.internalSeek(startKey)
if err != nil {
return nil, errors.Trace(err)
}
var rawKey []byte
var v []byte
// Check if the scan is not exceed this key's all versions and the value is not
// tombstone.
if kv.EncodedKey(it.Key()).Cmp(endKey) < 0 && !isTombstone(it.Value()) {
rawKey = it.Key()
v = it.Value()
}
// No such key (or it's tombstone).
if rawKey == nil {
return nil, kv.ErrNotExist
}
return bytes.CloneBytes(v), nil
}