Adding upstream version 2.5.1.

Signed-off-by: Daniel Baumann <daniel@debian.org>

index/upsidedown/store/goleveldb/reader.go

@@ -0,0 +1,68 @@
+//  Copyright (c) 2014 Couchbase, Inc.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// 		http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package goleveldb
+
+import (
+	"github.com/blevesearch/goleveldb/leveldb"
+	"github.com/blevesearch/goleveldb/leveldb/util"
+	store "github.com/blevesearch/upsidedown_store_api"
+)
+
+type Reader struct {
+	store    *Store
+	snapshot *leveldb.Snapshot
+}
+
+func (r *Reader) Get(key []byte) ([]byte, error) {
+	b, err := r.snapshot.Get(key, r.store.defaultReadOptions)
+	if err == leveldb.ErrNotFound {
+		return nil, nil
+	}
+	return b, err
+}
+
+func (r *Reader) MultiGet(keys [][]byte) ([][]byte, error) {
+	return store.MultiGet(r, keys)
+}
+
+func (r *Reader) PrefixIterator(prefix []byte) store.KVIterator {
+	byteRange := util.BytesPrefix(prefix)
+	iter := r.snapshot.NewIterator(byteRange, r.store.defaultReadOptions)
+	iter.First()
+	rv := Iterator{
+		store:    r.store,
+		iterator: iter,
+	}
+	return &rv
+}
+
+func (r *Reader) RangeIterator(start, end []byte) store.KVIterator {
+	byteRange := &util.Range{
+		Start: start,
+		Limit: end,
+	}
+	iter := r.snapshot.NewIterator(byteRange, r.store.defaultReadOptions)
+	iter.First()
+	rv := Iterator{
+		store:    r.store,
+		iterator: iter,
+	}
+	return &rv
+}
+
+func (r *Reader) Close() error {
+	r.snapshot.Release()
+	return nil
+}