示例#1
0
func (db *DB) newIterator(seq uint64, slice *util.Range, ro *opt.ReadOptions) *dbIter {
	var islice *util.Range
	if slice != nil {
		islice = &util.Range{}
		if slice.Start != nil {
			islice.Start = newIkey(slice.Start, kMaxSeq, ktSeek)
		}
		if slice.Limit != nil {
			islice.Limit = newIkey(slice.Limit, kMaxSeq, ktSeek)
		}
	}
	rawIter := db.newRawIterator(islice, ro)
	iter := &dbIter{
		db:     db,
		icmp:   db.s.icmp,
		iter:   rawIter,
		seq:    seq,
		strict: opt.GetStrict(db.s.o.Options, ro, opt.StrictReader),
		key:    make([]byte, 0),
		value:  make([]byte, 0),
	}
	atomic.AddInt32(&db.aliveIters, 1)
	runtime.SetFinalizer(iter, (*dbIter).Release)
	return iter
}
示例#2
0
func (v *version) getIterators(slice *util.Range, ro *opt.ReadOptions) (its []iterator.Iterator) {
	// Merge all level zero files together since they may overlap
	for _, t := range v.tables[0] {
		it := v.s.tops.newIterator(t, slice, ro)
		its = append(its, it)
	}

	strict := opt.GetStrict(v.s.o.Options, ro, opt.StrictReader)
	for _, tables := range v.tables[1:] {
		if len(tables) == 0 {
			continue
		}

		it := iterator.NewIndexedIterator(tables.newIndexIterator(v.s.tops, v.s.icmp, slice, ro), strict)
		its = append(its, it)
	}

	return
}
示例#3
0
func (db *DB) newRawIterator(slice *util.Range, ro *opt.ReadOptions) iterator.Iterator {
	em, fm := db.getMems()
	v := db.s.version()

	ti := v.getIterators(slice, ro)
	n := len(ti) + 2
	i := make([]iterator.Iterator, 0, n)
	emi := em.mdb.NewIterator(slice)
	emi.SetReleaser(&memdbReleaser{m: em})
	i = append(i, emi)
	if fm != nil {
		fmi := fm.mdb.NewIterator(slice)
		fmi.SetReleaser(&memdbReleaser{m: fm})
		i = append(i, fmi)
	}
	i = append(i, ti...)
	strict := opt.GetStrict(db.s.o.Options, ro, opt.StrictReader)
	mi := iterator.NewMergedIterator(i, db.s.icmp, strict)
	mi.SetReleaser(&versionReleaser{v: v})
	return mi
}