blocklog

type BLog ¶

type BLog struct {
	sync.RWMutex
	// contains filtered or unexported fields
}

BLog is an external append only log of the blocks. Blocks should only be written

• to the log after they're irreversible as the log is append only. There is a secondary
• index file of only block positions that enables O(1) random access lookup by block number. *
• A block data in the BLog is formatted as len+payload, len is a uint32 *
• +---------+----------------+---------+----------------+-----+------------+-------------------+
• | Block 1 | Pos of Block 1 | Block 2 | Pos of Block 2 | ... | Head Block | Pos of Head Block |
• +---------+----------------+---------+----------------+-----+------------+-------------------+ *
• +----------------+----------------+-----+-------------------+
• | Pos of Block 1 | Pos of Block 2 | ... | Pos of Head Block |
• +----------------+----------------+-----+-------------------+ * *
• Blocks can be accessed at random via block number through the index file. Seek to 8 * (block_num - 1)
• to find the position of the block in the main file. *
• The main file is the only file that needs to persist. The index file can be reconstructed during a
• linear scan of the main file.

func (bl *BLog) Append(sb common.ISignedBlock) error

func (bl *BLog) Empty() bool

func (bl *BLog) Open(dir string) (err error)

func (bl *BLog) ReadBlock(sb common.ISignedBlock, blockNum int64) error

func (bl *BLog) Remove(dir string)

func (bl *BLog) Size() int64