Method WriteDBHeader

core/encoder.go:205–235

WriteDBHeader write db index and resize db into rdb file

(dbIndex uint, keyCount, ttlCount uint64)

// WriteDBHeader write db index and resize db into rdb file
func (enc *Encoder) WriteDBHeader(dbIndex uint, keyCount, ttlCount uint64) error {
	if !enc.validateStateChange(writtenDBHeaderState) {
		return fmt.Errorf("cannot writing db header at state: %s", enc.state)
	}
	if _, ok := enc.existDB[dbIndex]; ok {
		return fmt.Errorf("db %d existed", dbIndex)
	}
	enc.existDB[dbIndex] = struct{}{}
	err := enc.write([]byte{opCodeSelectDB})
	if err != nil {
		return err
	}
	err = enc.writeLength(uint64(dbIndex))
	if err != nil {
		return err
	}
	err = enc.write([]byte{opCodeResizeDB})
	if err != nil {
		return err
	}
	err = enc.writeLength(keyCount)
	if err != nil {
		return err
	}
	err = enc.writeLength(ttlCount)
	if err != nil {
		return err
	}
	enc.state = writtenDBHeaderState
	return nil
}

// WriteEnd writes EOF and crc sum
func (enc *Encoder) WriteEnd() error {