add other session providers (#5963)

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

@@ -0,0 +1,171 @@
+package nodb
+
+import (
+	"fmt"
+	"sync"
+
+	"github.com/lunny/nodb/store"
+)
+
+type ibucket interface {
+	Get(key []byte) ([]byte, error)
+
+	Put(key []byte, value []byte) error
+	Delete(key []byte) error
+
+	NewIterator() *store.Iterator
+
+	NewWriteBatch() store.WriteBatch
+
+	RangeIterator(min []byte, max []byte, rangeType uint8) *store.RangeLimitIterator
+	RevRangeIterator(min []byte, max []byte, rangeType uint8) *store.RangeLimitIterator
+	RangeLimitIterator(min []byte, max []byte, rangeType uint8, offset int, count int) *store.RangeLimitIterator
+	RevRangeLimitIterator(min []byte, max []byte, rangeType uint8, offset int, count int) *store.RangeLimitIterator
+}
+
+type DB struct {
+	l *Nodb
+
+	sdb *store.DB
+
+	bucket ibucket
+
+	index uint8
+
+	kvBatch   *batch
+	listBatch *batch
+	hashBatch *batch
+	zsetBatch *batch
+	binBatch  *batch
+	setBatch  *batch
+
+	status uint8
+}
+
+func (l *Nodb) newDB(index uint8) *DB {
+	d := new(DB)
+
+	d.l = l
+
+	d.sdb = l.ldb
+
+	d.bucket = d.sdb
+
+	d.status = DBAutoCommit
+	d.index = index
+
+	d.kvBatch = d.newBatch()
+	d.listBatch = d.newBatch()
+	d.hashBatch = d.newBatch()
+	d.zsetBatch = d.newBatch()
+	d.binBatch = d.newBatch()
+	d.setBatch = d.newBatch()
+
+	return d
+}
+
+func (db *DB) newBatch() *batch {
+	return db.l.newBatch(db.bucket.NewWriteBatch(), &dbBatchLocker{l: &sync.Mutex{}, wrLock: &db.l.wLock}, nil)
+}
+
+func (db *DB) Index() int {
+	return int(db.index)
+}
+
+func (db *DB) IsAutoCommit() bool {
+	return db.status == DBAutoCommit
+}
+
+func (db *DB) FlushAll() (drop int64, err error) {
+	all := [...](func() (int64, error)){
+		db.flush,
+		db.lFlush,
+		db.hFlush,
+		db.zFlush,
+		db.bFlush,
+		db.sFlush}
+
+	for _, flush := range all {
+		if n, e := flush(); e != nil {
+			err = e
+			return
+		} else {
+			drop += n
+		}
+	}
+
+	return
+}
+
+func (db *DB) newEliminator() *elimination {
+	eliminator := newEliminator(db)
+
+	eliminator.regRetireContext(KVType, db.kvBatch, db.delete)
+	eliminator.regRetireContext(ListType, db.listBatch, db.lDelete)
+	eliminator.regRetireContext(HashType, db.hashBatch, db.hDelete)
+	eliminator.regRetireContext(ZSetType, db.zsetBatch, db.zDelete)
+	eliminator.regRetireContext(BitType, db.binBatch, db.bDelete)
+	eliminator.regRetireContext(SetType, db.setBatch, db.sDelete)
+
+	return eliminator
+}
+
+func (db *DB) flushRegion(t *batch, minKey []byte, maxKey []byte) (drop int64, err error) {
+	it := db.bucket.RangeIterator(minKey, maxKey, store.RangeROpen)
+	for ; it.Valid(); it.Next() {
+		t.Delete(it.RawKey())
+		drop++
+		if drop&1023 == 0 {
+			if err = t.Commit(); err != nil {
+				return
+			}
+		}
+	}
+	it.Close()
+	return
+}
+
+func (db *DB) flushType(t *batch, dataType byte) (drop int64, err error) {
+	var deleteFunc func(t *batch, key []byte) int64
+	var metaDataType byte
+	switch dataType {
+	case KVType:
+		deleteFunc = db.delete
+		metaDataType = KVType
+	case ListType:
+		deleteFunc = db.lDelete
+		metaDataType = LMetaType
+	case HashType:
+		deleteFunc = db.hDelete
+		metaDataType = HSizeType
+	case ZSetType:
+		deleteFunc = db.zDelete
+		metaDataType = ZSizeType
+	case BitType:
+		deleteFunc = db.bDelete
+		metaDataType = BitMetaType
+	case SetType:
+		deleteFunc = db.sDelete
+		metaDataType = SSizeType
+	default:
+		return 0, fmt.Errorf("invalid data type: %s", TypeName[dataType])
+	}
+
+	var keys [][]byte
+	keys, err = db.scan(metaDataType, nil, 1024, false, "")
+	for len(keys) != 0 || err != nil {
+		for _, key := range keys {
+			deleteFunc(t, key)
+			db.rmExpire(t, dataType, key)
+
+		}
+
+		if err = t.Commit(); err != nil {
+			return
+		} else {
+			drop += int64(len(keys))
+		}
+		keys, err = db.scan(metaDataType, nil, 1024, false, "")
+	}
+	return
+}