Golang BlockHeader.Bytes方法代碼示例

//.........這裏部分代碼省略.........
		var err error
		k := tickettreap.Key(undo.TicketHash)
		v := &tickettreap.Value{
			Height:  undo.TicketHeight,
			Missed:  undo.Missed,
			Revoked: undo.Revoked,
			Spent:   undo.Spent,
			Expired: undo.Expired,
		}

		switch {
		// All flags are unset; this is a newly added ticket.
		// Remove it from the list of live tickets.
		case !undo.Missed && !undo.Revoked && !undo.Spent:
			restoredNode.liveTickets, err =
				safeDelete(restoredNode.liveTickets, k)
			if err != nil {
				return nil, err
			}

		// The ticket was missed and revoked.  It needs to
		// be moved from the revoked ticket treap to the
		// missed ticket treap.
		case undo.Missed && undo.Revoked:
			v.Revoked = false
			restoredNode.revokedTickets, err =
				safeDelete(restoredNode.revokedTickets, k)
			if err != nil {
				return nil, err
			}
			restoredNode.missedTickets, err =
				safePut(restoredNode.missedTickets, k, v)
			if err != nil {
				return nil, err
			}

		// The ticket was missed and was previously live.
		// Remove it from the missed tickets bucket and
		// move it to the live tickets bucket.
		case undo.Missed && !undo.Revoked:
			// Expired tickets could never have been
			// winners.
			if !undo.Expired {
				restoredNode.nextWinners = append(restoredNode.nextWinners,
					undo.TicketHash)
				stateBuffer = append(stateBuffer,
					undo.TicketHash[:]...)
			} else {
				v.Expired = false
			}
			v.Missed = false
			restoredNode.missedTickets, err =
				safeDelete(restoredNode.missedTickets, k)
			if err != nil {
				return nil, err
			}
			restoredNode.liveTickets, err =
				safePut(restoredNode.liveTickets, k, v)
			if err != nil {
				return nil, err
			}

		// The ticket was spent.  Reinsert it into the live
		// tickets treap and add it to the list of next
		// winners.
		case undo.Spent:
			v.Spent = false
			restoredNode.nextWinners = append(restoredNode.nextWinners,
				undo.TicketHash)
			stateBuffer = append(stateBuffer, undo.TicketHash[:]...)
			restoredNode.liveTickets, err =
				safePut(restoredNode.liveTickets, k, v)
			if err != nil {
				return nil, err
			}

		default:
			return nil, stakeRuleError(ErrMemoryCorruption,
				"unknown ticket state in undo data")
		}
	}

	if node.height >= uint32(node.params.StakeValidationHeight) {
		phB, err := parentHeader.Bytes()
		if err != nil {
			return nil, err
		}
		prng := NewHash256PRNG(phB)
		_, err = findTicketIdxs(int64(restoredNode.liveTickets.Len()),
			int(node.params.TicketsPerBlock), prng)
		if err != nil {
			return nil, err
		}
		lastHash := prng.StateHash()
		stateBuffer = append(stateBuffer, lastHash[:]...)
		copy(restoredNode.finalState[:], chainhash.HashFuncB(stateBuffer)[0:6])
	}

	return restoredNode, nil
}

// LoadBestNode is used when the blockchain is initialized, to get the initial
// stake node from the database bucket.  The blockchain must pass the height
// and the blockHash to confirm that the ticket database is on the same
// location in the blockchain as the blockchain itself.  This function also
// checks to ensure that the database has not failed the upgrade process and
// reports the current version.  Upgrades are also handled by this function,
// when they become applicable.
func LoadBestNode(dbTx database.Tx, height uint32, blockHash chainhash.Hash, header wire.BlockHeader, params *chaincfg.Params) (*Node, error) {
	info, err := ticketdb.DbFetchDatabaseInfo(dbTx)
	if err != nil {
		return nil, err
	}

	// Compare the tip and make sure it matches.
	state, err := ticketdb.DbFetchBestState(dbTx)
	if err != nil {
		return nil, err
	}
	if state.Hash != blockHash || state.Height != height {
		return nil, stakeRuleError(ErrDatabaseCorrupt, "best state corruption")
	}

	// Restore the best node treaps form the database.
	node := new(Node)
	node.height = height
	node.params = params
	node.liveTickets, err = ticketdb.DbLoadAllTickets(dbTx,
		dbnamespace.LiveTicketsBucketName)
	if err != nil {
		return nil, err
	}
	if node.liveTickets.Len() != int(state.Live) {
		return nil, stakeRuleError(ErrDatabaseCorrupt,
			fmt.Sprintf("live tickets corruption (got "+
				"%v in state but loaded %v)", int(state.Live),
				node.liveTickets.Len()))
	}
	node.missedTickets, err = ticketdb.DbLoadAllTickets(dbTx,
		dbnamespace.MissedTicketsBucketName)
	if err != nil {
		return nil, err
	}
	if node.missedTickets.Len() != int(state.Missed) {
		return nil, stakeRuleError(ErrDatabaseCorrupt,
			fmt.Sprintf("missed tickets corruption (got "+
				"%v in state but loaded %v)", int(state.Missed),
				node.missedTickets.Len()))
	}
	node.revokedTickets, err = ticketdb.DbLoadAllTickets(dbTx,
		dbnamespace.RevokedTicketsBucketName)
	if err != nil {
		return nil, err
	}
	if node.revokedTickets.Len() != int(state.Revoked) {
		return nil, stakeRuleError(ErrDatabaseCorrupt,
			fmt.Sprintf("revoked tickets corruption (got "+
				"%v in state but loaded %v)", int(state.Revoked),
				node.revokedTickets.Len()))
	}

	// Restore the node undo and new tickets data.
	node.databaseUndoUpdate, err = ticketdb.DbFetchBlockUndoData(dbTx, height)
	if err != nil {
		return nil, err
	}
	node.databaseBlockTickets, err = ticketdb.DbFetchNewTickets(dbTx, height)
	if err != nil {
		return nil, err
	}

	// Restore the next winners for the node.
	node.nextWinners = make([]chainhash.Hash, 0)
	if node.height >= uint32(node.params.StakeValidationHeight-1) {
		node.nextWinners = make([]chainhash.Hash, len(state.NextWinners))
		for i := range state.NextWinners {
			node.nextWinners[i] = state.NextWinners[i]
		}

		// Calculate the final state from the block header.
		stateBuffer := make([]byte, 0,
			(node.params.TicketsPerBlock+1)*chainhash.HashSize)
		for _, ticketHash := range node.nextWinners {
			stateBuffer = append(stateBuffer, ticketHash[:]...)
		}
		hB, err := header.Bytes()
		if err != nil {
			return nil, err
		}
		prng := NewHash256PRNG(hB)
		_, err = findTicketIdxs(int64(node.liveTickets.Len()),
			int(node.params.TicketsPerBlock), prng)
		if err != nil {
			return nil, err
		}
		lastHash := prng.StateHash()
		stateBuffer = append(stateBuffer, lastHash[:]...)
		copy(node.finalState[:], chainhash.HashFuncB(stateBuffer)[0:6])
	}

	log.Infof("Stake database version %v loaded", info.Version)
//.........這裏部分代碼省略.........

//.........這裏部分代碼省略.........
				})
		}

		// Process all the revocations, moving them from the missed to the
		// revoked treap and recording them in the undo data.
		for _, revokedTicket := range revokedTickets {
			v, err := safeGet(connectedNode.missedTickets,
				tickettreap.Key(revokedTicket))
			if err != nil {
				return nil, err
			}
			v.Revoked = true
			connectedNode.missedTickets, err =
				safeDelete(connectedNode.missedTickets,
					tickettreap.Key(revokedTicket))
			if err != nil {
				return nil, err
			}
			connectedNode.revokedTickets, err =
				safePut(connectedNode.revokedTickets,
					tickettreap.Key(revokedTicket), v)
			if err != nil {
				return nil, err
			}

			connectedNode.databaseUndoUpdate =
				append(connectedNode.databaseUndoUpdate, ticketdb.UndoTicketData{
					TicketHash:   revokedTicket,
					TicketHeight: v.Height,
					Missed:       v.Missed,
					Revoked:      v.Revoked,
					Spent:        v.Spent,
					Expired:      v.Expired,
				})
		}
	}

	// Add all the new tickets.
	for _, newTicket := range newTickets {
		k := tickettreap.Key(newTicket)
		v := &tickettreap.Value{
			Height:  connectedNode.height,
			Missed:  false,
			Revoked: false,
			Spent:   false,
			Expired: false,
		}
		connectedNode.liveTickets, err =
			safePut(connectedNode.liveTickets, k, v)
		if err != nil {
			return nil, err
		}

		connectedNode.databaseUndoUpdate =
			append(connectedNode.databaseUndoUpdate, ticketdb.UndoTicketData{
				TicketHash:   newTicket,
				TicketHeight: v.Height,
				Missed:       v.Missed,
				Revoked:      v.Revoked,
				Spent:        v.Spent,
				Expired:      v.Expired,
			})
	}

	// The first block voted on is at StakeEnabledHeight, so begin calculating
	// winners at the block before StakeEnabledHeight.
	if connectedNode.height >=
		uint32(connectedNode.params.StakeValidationHeight-1) {
		// Find the next set of winners.
		hB, err := header.Bytes()
		if err != nil {
			return nil, err
		}
		prng := NewHash256PRNG(hB)
		idxs, err := findTicketIdxs(int64(connectedNode.liveTickets.Len()),
			int(connectedNode.params.TicketsPerBlock), prng)
		if err != nil {
			return nil, err
		}

		stateBuffer := make([]byte, 0,
			(connectedNode.params.TicketsPerBlock+1)*chainhash.HashSize)
		nextWinnersKeys, err := fetchWinners(idxs, connectedNode.liveTickets)
		if err != nil {
			return nil, err
		}

		for _, treapKey := range nextWinnersKeys {
			ticketHash := chainhash.Hash(*treapKey)
			connectedNode.nextWinners = append(connectedNode.nextWinners,
				ticketHash)
			stateBuffer = append(stateBuffer, ticketHash[:]...)
		}
		lastHash := prng.StateHash()
		stateBuffer = append(stateBuffer, lastHash[:]...)
		copy(connectedNode.finalState[:], chainhash.HashFuncB(stateBuffer)[0:6])
	}

	return connectedNode, nil
}

// estimateNextStakeDifficulty returns a user-specified estimate for the next
// stake difficulty, with the passed ticketsInWindow indicating the number of
// fresh stake to pretend exists within this window. Optionally the user can
// also override this variable with useMaxTickets, which simply plugs in the
// maximum number of tickets the user can try.
func (b *BlockChain) estimateNextStakeDifficulty(curNode *blockNode,
	ticketsInWindow int64, useMaxTickets bool) (int64, error) {
	alpha := b.chainParams.StakeDiffAlpha
	stakeDiffStartHeight := int64(b.chainParams.CoinbaseMaturity) +
		1
	maxRetarget := int64(b.chainParams.RetargetAdjustmentFactor)
	TicketPoolWeight := int64(b.chainParams.TicketPoolSizeWeight)

	// Number of nodes to traverse while calculating difficulty.
	nodesToTraverse := (b.chainParams.StakeDiffWindowSize *
		b.chainParams.StakeDiffWindows)

	// Genesis block. Block at height 1 has these parameters.
	if curNode == nil ||
		curNode.height < stakeDiffStartHeight {
		return b.chainParams.MinimumStakeDiff, nil
	}

	// Create a fake blockchain on top of the current best node with
	// the number of freshly purchased tickets as indicated by the
	// user.
	oldDiff := curNode.header.SBits
	topNode := curNode
	if (curNode.height+1)%b.chainParams.StakeDiffWindowSize != 0 {
		nextAdjHeight := ((curNode.height /
			b.chainParams.StakeDiffWindowSize) + 1) *
			b.chainParams.StakeDiffWindowSize
		maxTickets := (nextAdjHeight - curNode.height) *
			int64(b.chainParams.MaxFreshStakePerBlock)

		// If the user has indicated that the automatically
		// calculated maximum amount of tickets should be
		// used, plug that in here.
		if useMaxTickets {
			ticketsInWindow = maxTickets
		}

		// Double check to make sure there isn't too much.
		if ticketsInWindow > maxTickets {
			return 0, fmt.Errorf("too much fresh stake to be used "+
				"in evaluation requested; max %v, got %v", maxTickets,
				ticketsInWindow)
		}

		// Insert all the tickets into bogus nodes that will be
		// used to calculate the next difficulty below.
		ticketsToInsert := ticketsInWindow
		for i := curNode.height + 1; i < nextAdjHeight; i++ {
			emptyHeader := new(wire.BlockHeader)
			emptyHeader.Height = uint32(i)

			// User a constant pool size for estimate, since
			// this has much less fluctuation than freshStake.
			// TODO Use a better pool size estimate?
			emptyHeader.PoolSize = curNode.header.PoolSize

			// Insert the fake fresh stake into each block,
			// decrementing the amount we need to use each
			// time until we hit 0.
			freshStake := b.chainParams.MaxFreshStakePerBlock
			if int64(freshStake) > ticketsToInsert {
				freshStake = uint8(ticketsToInsert)
				ticketsToInsert -= ticketsToInsert
			} else {
				ticketsToInsert -= int64(b.chainParams.MaxFreshStakePerBlock)
			}
			emptyHeader.FreshStake = freshStake

			// Connect the header.
			emptyHeader.PrevBlock = topNode.hash

			// Make up a node hash.
			hB, err := emptyHeader.Bytes()
			if err != nil {
				return 0, err
			}
			emptyHeaderHash := chainhash.HashFuncH(hB)

			thisNode := new(blockNode)
			thisNode.header = *emptyHeader
			thisNode.hash = emptyHeaderHash
			thisNode.height = i
			thisNode.parent = topNode
			topNode = thisNode
		}
	}

	// The target size of the ticketPool in live tickets. Recast these as int64
	// to avoid possible overflows for large sizes of either variable in
	// params.
	targetForTicketPool := int64(b.chainParams.TicketsPerBlock) *
		int64(b.chainParams.TicketPoolSize)

	// Initialize bigInt slice for the percentage changes for each window period
	// above or below the target.
//.........這裏部分代碼省略.........