forked from mirror/ledisdb
76 lines
1.3 KiB
Go
76 lines
1.3 KiB
Go
package ledis
|
|
|
|
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()
|
|
|
|
m.DB.lbkeys = db.lbkeys
|
|
|
|
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
|
|
}
|