Beispiel #1
0
func (r *Reader) NewIterator(slice *util.Range, ro *opt.ReadOptions) iterator.Iterator {
	if r.err != nil {
		return iterator.NewEmptyIterator(r.err)
	}

	index := &indexIter{
		blockIter:   *r.indexBlock.newIterator(slice, true, nil),
		tableReader: r,
		slice:       slice,
		checksum:    ro.GetStrict(opt.StrictBlockChecksum),
		fillCache:   !ro.GetDontFillCache(),
	}
	return iterator.NewIndexedIterator(index, r.strictIter || ro.GetStrict(opt.StrictIterator), false)
}
Beispiel #2
0
// Find finds key/value pair whose key is greater than or equal to the
// given key. It returns ErrNotFound if the table doesn't contain
// such pair.
//
// The caller should not modify the contents of the returned slice, but
// it is safe to modify the contents of the argument after Find returns.
func (r *Reader) Find(key []byte, ro *opt.ReadOptions) (rkey, value []byte, err error) {
	if r.err != nil {
		err = r.err
		return
	}

	index := r.indexBlock.newIterator(nil, true, nil)
	defer index.Release()
	if !index.Seek(key) {
		err = index.Error()
		if err == nil {
			err = ErrNotFound
		}
		return
	}
	dataBH, n := decodeBlockHandle(index.Value())
	if n == 0 {
		err = errors.New("leveldb/table: Reader: invalid table (bad data block handle)")
		return
	}
	if r.filterBlock != nil && !r.filterBlock.contains(dataBH.offset, key) {
		err = ErrNotFound
		return
	}
	data := r.getDataIter(dataBH, nil, ro.GetStrict(opt.StrictBlockChecksum), !ro.GetDontFillCache())
	defer data.Release()
	if !data.Seek(key) {
		err = data.Error()
		if err == nil {
			err = ErrNotFound
		}
		return
	}
	// Don't use block buffer, no need to copy the buffer.
	rkey = data.Key()
	// Use block buffer, and since the buffer will be recycled, the buffer
	// need to be copied.
	value = append([]byte{}, data.Value()...)
	return
}