Adding upstream version 2.5.1.

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

index/upsidedown/store/moss/writer.go

@@ -0,0 +1,97 @@
+//  Copyright (c) 2016 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 moss
+
+import (
+	"fmt"
+
+	store "github.com/blevesearch/upsidedown_store_api"
+
+	"github.com/couchbase/moss"
+)
+
+type Writer struct {
+	s *Store
+}
+
+func (w *Writer) NewBatch() store.KVBatch {
+	b, err := w.s.ms.NewBatch(0, 0)
+	if err != nil {
+		return nil
+	}
+
+	return &Batch{
+		store: w.s,
+		merge: store.NewEmulatedMerge(w.s.mo),
+		batch: b,
+	}
+}
+
+func (w *Writer) NewBatchEx(options store.KVBatchOptions) (
+	[]byte, store.KVBatch, error) {
+	numOps := options.NumSets + options.NumDeletes + options.NumMerges
+
+	b, err := w.s.ms.NewBatch(numOps, options.TotalBytes)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	buf, err := b.Alloc(options.TotalBytes)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	return buf, &Batch{
+		store:   w.s,
+		merge:   store.NewEmulatedMerge(w.s.mo),
+		batch:   b,
+		buf:     buf,
+		bufUsed: 0,
+	}, nil
+}
+
+func (w *Writer) ExecuteBatch(b store.KVBatch) (err error) {
+	batch, ok := b.(*Batch)
+	if !ok {
+		return fmt.Errorf("wrong type of batch")
+	}
+
+	for kStr, mergeOps := range batch.merge.Merges {
+		for _, v := range mergeOps {
+			if batch.buf != nil {
+				kLen := len(kStr)
+				vLen := len(v)
+				kBuf := batch.buf[batch.bufUsed : batch.bufUsed+kLen]
+				vBuf := batch.buf[batch.bufUsed+kLen : batch.bufUsed+kLen+vLen]
+				copy(kBuf, kStr)
+				copy(vBuf, v)
+				batch.bufUsed += kLen + vLen
+				err = batch.batch.AllocMerge(kBuf, vBuf)
+			} else {
+				err = batch.batch.Merge([]byte(kStr), v)
+			}
+			if err != nil {
+				return err
+			}
+		}
+	}
+
+	return w.s.ms.ExecuteBatch(batch.batch, moss.WriteOptions{})
+}
+
+func (w *Writer) Close() error {
+	w.s = nil
+	return nil
+}