add other session providers (#5963)

vendor/github.com/lunny/nodb/batch.go

@@ -0,0 +1,106 @@
+package nodb
+
+import (
+	"sync"
+
+	"github.com/lunny/nodb/store"
+)
+
+type batch struct {
+	l *Nodb
+
+	store.WriteBatch
+
+	sync.Locker
+
+	logs [][]byte
+
+	tx *Tx
+}
+
+func (b *batch) Commit() error {
+	b.l.commitLock.Lock()
+	defer b.l.commitLock.Unlock()
+
+	err := b.WriteBatch.Commit()
+
+	if b.l.binlog != nil {
+		if err == nil {
+			if b.tx == nil {
+				b.l.binlog.Log(b.logs...)
+			} else {
+				b.tx.logs = append(b.tx.logs, b.logs...)
+			}
+		}
+		b.logs = [][]byte{}
+	}
+
+	return err
+}
+
+func (b *batch) Lock() {
+	b.Locker.Lock()
+}
+
+func (b *batch) Unlock() {
+	if b.l.binlog != nil {
+		b.logs = [][]byte{}
+	}
+	b.WriteBatch.Rollback()
+	b.Locker.Unlock()
+}
+
+func (b *batch) Put(key []byte, value []byte) {
+	if b.l.binlog != nil {
+		buf := encodeBinLogPut(key, value)
+		b.logs = append(b.logs, buf)
+	}
+	b.WriteBatch.Put(key, value)
+}
+
+func (b *batch) Delete(key []byte) {
+	if b.l.binlog != nil {
+		buf := encodeBinLogDelete(key)
+		b.logs = append(b.logs, buf)
+	}
+	b.WriteBatch.Delete(key)
+}
+
+type dbBatchLocker struct {
+	l      *sync.Mutex
+	wrLock *sync.RWMutex
+}
+
+func (l *dbBatchLocker) Lock() {
+	l.wrLock.RLock()
+	l.l.Lock()
+}
+
+func (l *dbBatchLocker) Unlock() {
+	l.l.Unlock()
+	l.wrLock.RUnlock()
+}
+
+type txBatchLocker struct {
+}
+
+func (l *txBatchLocker) Lock()   {}
+func (l *txBatchLocker) Unlock() {}
+
+type multiBatchLocker struct {
+}
+
+func (l *multiBatchLocker) Lock()   {}
+func (l *multiBatchLocker) Unlock() {}
+
+func (l *Nodb) newBatch(wb store.WriteBatch, locker sync.Locker, tx *Tx) *batch {
+	b := new(batch)
+	b.l = l
+	b.WriteBatch = wb
+
+	b.tx = tx
+	b.Locker = locker
+
+	b.logs = [][]byte{}
+	return b
+}