Golang Options.GetBlockSize方法代码示例

// NewWriter creates a new initialized table writer for the file.
//
// Table writer is not safe for concurrent use.
func NewWriter(f io.Writer, o *opt.Options) *Writer {
	w := &Writer{
		writer:          f,
		cmp:             o.GetComparer(),
		filter:          o.GetFilter(),
		compression:     o.GetCompression(),
		blockSize:       o.GetBlockSize(),
		comparerScratch: make([]byte, 0),
	}
	// data block
	w.dataBlock.restartInterval = o.GetBlockRestartInterval()
	// The first 20-bytes are used for encoding block handle.
	w.dataBlock.scratch = w.scratch[20:]
	// index block
	w.indexBlock.restartInterval = 1
	w.indexBlock.scratch = w.scratch[20:]
	// filter block
	if w.filter != nil {
		w.filterBlock.generator = w.filter.NewGenerator()
		w.filterBlock.flush(0)
	}
	return w
}

// NewReader creates a new initialized table reader for the file.
// The cache and bpool is optional and can be nil.
//
// The returned table reader instance is goroutine-safe.
func NewReader(f io.ReaderAt, size int64, cache cache.Namespace, bpool *util.BufferPool, o *opt.Options) *Reader {
	if bpool == nil {
		bpool = util.NewBufferPool(o.GetBlockSize() + blockTrailerLen)
	}
	r := &Reader{
		reader:     f,
		cache:      cache,
		bpool:      bpool,
		cmp:        o.GetComparer(),
		checksum:   o.GetStrict(opt.StrictBlockChecksum),
		strictIter: o.GetStrict(opt.StrictIterator),
	}
	if f == nil {
		r.err = errors.New("leveldb/table: Reader: nil file")
		return r
	}
	if size < footerLen {
		r.err = errors.New("leveldb/table: Reader: invalid table (file size is too small)")
		return r
	}
	var footer [footerLen]byte
	if _, err := r.reader.ReadAt(footer[:], size-footerLen); err != nil && err != io.EOF {
		r.err = fmt.Errorf("leveldb/table: Reader: invalid table (could not read footer): %v", err)
	}
	if string(footer[footerLen-len(magic):footerLen]) != magic {
		r.err = errors.New("leveldb/table: Reader: invalid table (bad magic number)")
		return r
	}
	// Decode the metaindex block handle.
	metaBH, n := decodeBlockHandle(footer[:])
	if n == 0 {
		r.err = errors.New("leveldb/table: Reader: invalid table (bad metaindex block handle)")
		return r
	}
	// Decode the index block handle.
	indexBH, n := decodeBlockHandle(footer[n:])
	if n == 0 {
		r.err = errors.New("leveldb/table: Reader: invalid table (bad index block handle)")
		return r
	}
	// Read index block.
	r.indexBlock, r.err = r.readBlock(indexBH, true)
	if r.err != nil {
		return r
	}
	// Read metaindex block.
	metaBlock, err := r.readBlock(metaBH, true)
	if err != nil {
		r.err = err
		return r
	}
	// Set data end.
	r.dataEnd = int64(metaBH.offset)
	metaIter := metaBlock.newIterator(nil, false, nil)
	for metaIter.Next() {
		key := string(metaIter.Key())
		if !strings.HasPrefix(key, "filter.") {
			continue
		}
		fn := key[7:]
		var filter filter.Filter
		if f0 := o.GetFilter(); f0 != nil && f0.Name() == fn {
			filter = f0
		} else {
			for _, f0 := range o.GetAltFilters() {
				if f0.Name() == fn {
					filter = f0
					break
				}
			}
		}
		if filter != nil {
			filterBH, n := decodeBlockHandle(metaIter.Value())
			if n == 0 {
				continue
			}
			// Update data end.
			r.dataEnd = int64(filterBH.offset)
			filterBlock, err := r.readFilterBlock(filterBH, filter)
			if err != nil {
				continue
			}
			r.filterBlock = filterBlock
			break
		}
	}
	metaIter.Release()
	return r
}

func recoverTable(s *session, o *opt.Options) error {
	// Get all tables and sort it by file number.
	tableFiles_, err := s.getFiles(storage.TypeTable)
	if err != nil {
		return err
	}
	tableFiles := files(tableFiles_)
	tableFiles.sort()

	var mSeq uint64
	var good, corrupted int
	rec := new(sessionRecord)
	bpool := util.NewBufferPool(o.GetBlockSize() + 5)
	buildTable := func(iter iterator.Iterator) (tmp storage.File, size int64, err error) {
		tmp = s.newTemp()
		writer, err := tmp.Create()
		if err != nil {
			return
		}
		defer func() {
			writer.Close()
			if err != nil {
				tmp.Remove()
				tmp = nil
			}
		}()

		// Copy entries.
		tw := table.NewWriter(writer, o)
		for iter.Next() {
			key := iter.Key()
			if validIkey(key) {
				err = tw.Append(key, iter.Value())
				if err != nil {
					return
				}
			}
		}
		err = iter.Error()
		if err != nil {
			return
		}
		err = tw.Close()
		if err != nil {
			return
		}
		err = writer.Sync()
		if err != nil {
			return
		}
		size = int64(tw.BytesLen())
		return
	}
	recoverTable := func(file storage.File) error {
		s.logf("[email protected] recovering @%d", file.Num())
		reader, err := file.Open()
		if err != nil {
			return err
		}
		defer reader.Close()

		// Get file size.
		size, err := reader.Seek(0, 2)
		if err != nil {
			return err
		}

		var tSeq uint64
		var tgood, tcorrupted, blockerr int
		var imin, imax []byte
		tr := table.NewReader(reader, size, nil, bpool, o)
		iter := tr.NewIterator(nil, nil)
		iter.(iterator.ErrorCallbackSetter).SetErrorCallback(func(err error) {
			s.logf("[email protected] found error @%d %q", file.Num(), err)
			blockerr++
		})

		// Scan the table.
		for iter.Next() {
			key := iter.Key()
			_, seq, _, ok := parseIkey(key)
			if !ok {
				tcorrupted++
				continue
			}
			tgood++
			if seq > tSeq {
				tSeq = seq
			}
			if imin == nil {
				imin = append([]byte{}, key...)
			}
			imax = append(imax[:0], key...)
		}
		if err := iter.Error(); err != nil {
			iter.Release()
			return err
		}
		iter.Release()

//.........这里部分代码省略.........

func recoverTable(s *session, o *opt.Options) error {
	o = dupOptions(o)
	// Mask StrictReader, lets StrictRecovery doing its job.
	o.Strict &= ^opt.StrictReader

	// Get all tables and sort it by file number.
	tableFiles_, err := s.getFiles(storage.TypeTable)
	if err != nil {
		return err
	}
	tableFiles := files(tableFiles_)
	tableFiles.sort()

	var (
		maxSeq                                                            uint64
		recoveredKey, goodKey, corruptedKey, corruptedBlock, droppedTable int

		// We will drop corrupted table.
		strict = o.GetStrict(opt.StrictRecovery)

		rec   = &sessionRecord{numLevel: o.GetNumLevel()}
		bpool = util.NewBufferPool(o.GetBlockSize() + 5)
	)
	buildTable := func(iter iterator.Iterator) (tmp storage.File, size int64, err error) {
		tmp = s.newTemp()
		writer, err := tmp.Create()
		if err != nil {
			return
		}
		defer func() {
			writer.Close()
			if err != nil {
				tmp.Remove()
				tmp = nil
			}
		}()

		// Copy entries.
		tw := table.NewWriter(writer, o)
		for iter.Next() {
			key := iter.Key()
			if validIkey(key) {
				err = tw.Append(key, iter.Value())
				if err != nil {
					return
				}
			}
		}
		err = iter.Error()
		if err != nil {
			return
		}
		err = tw.Close()
		if err != nil {
			return
		}
		err = writer.Sync()
		if err != nil {
			return
		}
		size = int64(tw.BytesLen())
		return
	}
	recoverTable := func(file storage.File) error {
		s.logf("[email protected] recovering @%d", file.Num())
		reader, err := file.Open()
		if err != nil {
			return err
		}
		var closed bool
		defer func() {
			if !closed {
				reader.Close()
			}
		}()

		// Get file size.
		size, err := reader.Seek(0, 2)
		if err != nil {
			return err
		}

		var (
			tSeq                                     uint64
			tgoodKey, tcorruptedKey, tcorruptedBlock int
			imin, imax                               []byte
		)
		tr, err := table.NewReader(reader, size, storage.NewFileInfo(file), nil, bpool, o)
		if err != nil {
			return err
		}
		iter := tr.NewIterator(nil, nil)
		iter.(iterator.ErrorCallbackSetter).SetErrorCallback(func(err error) {
			if errors.IsCorrupted(err) {
				s.logf("[email protected] block corruption @%d %q", file.Num(), err)
				tcorruptedBlock++
			}
		})

		// Scan the table.
//.........这里部分代码省略.........