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-rw-r--r--vendor/github.com/lunny/nodb/multi.go73
1 files changed, 73 insertions, 0 deletions
diff --git a/vendor/github.com/lunny/nodb/multi.go b/vendor/github.com/lunny/nodb/multi.go
new file mode 100644
index 0000000000..ca581ce9a2
--- /dev/null
+++ b/vendor/github.com/lunny/nodb/multi.go
@@ -0,0 +1,73 @@
+package nodb
+
+import (
+ "errors"
+ "fmt"
+)
+
+var (
+ ErrNestMulti = errors.New("nest multi not supported")
+ ErrMultiDone = errors.New("multi has been closed")
+)
+
+type Multi struct {
+ *DB
+}
+
+func (db *DB) IsInMulti() bool {
+ return db.status == DBInMulti
+}
+
+// begin a mutli to execute commands,
+// it will block any other write operations before you close the multi, unlike transaction, mutli can not rollback
+func (db *DB) Multi() (*Multi, error) {
+ if db.IsInMulti() {
+ return nil, ErrNestMulti
+ }
+
+ m := new(Multi)
+
+ m.DB = new(DB)
+ m.DB.status = DBInMulti
+
+ m.DB.l = db.l
+
+ m.l.wLock.Lock()
+
+ m.DB.sdb = db.sdb
+
+ m.DB.bucket = db.sdb
+
+ m.DB.index = db.index
+
+ m.DB.kvBatch = m.newBatch()
+ m.DB.listBatch = m.newBatch()
+ m.DB.hashBatch = m.newBatch()
+ m.DB.zsetBatch = m.newBatch()
+ m.DB.binBatch = m.newBatch()
+ m.DB.setBatch = m.newBatch()
+
+ return m, nil
+}
+
+func (m *Multi) newBatch() *batch {
+ return m.l.newBatch(m.bucket.NewWriteBatch(), &multiBatchLocker{}, nil)
+}
+
+func (m *Multi) Close() error {
+ if m.bucket == nil {
+ return ErrMultiDone
+ }
+ m.l.wLock.Unlock()
+ m.bucket = nil
+ return nil
+}
+
+func (m *Multi) Select(index int) error {
+ if index < 0 || index >= int(MaxDBNumber) {
+ return fmt.Errorf("invalid db index %d", index)
+ }
+
+ m.DB.index = uint8(index)
+ return nil
+}