Golang BlockHeader.FreshStake方法代码示例

// 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.
//.........这里部分代码省略.........