umint

README

umint

µ-minter for ppc

Documentation

Index

• func BigToCompact(n *big.Int) uint32
• func CheckStakeKernelHash(t *StakeKernelTemplate) (hashProofOfStake []byte, success bool, err error, minTarget *big.Int)
• func CompactToBig(compact uint32) *big.Int
• func CompactToDiff(bits uint32) (diff float32)
• func DiffToTarget(diff float32) (target *big.Int)
• func IncCompact(compact uint32) uint32
• type CoinStakeSource
• type StakeKernelTemplate
• type TxOut

Functions

func BigToCompact

func BigToCompact(n *big.Int) uint32

BigToCompact converts a whole number N to a compact representation using an unsigned 32-bit number. The compact representation only provides 23 bits of precision, so values larger than (2^23 - 1) only encode the most significant digits of the number. See CompactToBig for details.

func CheckStakeKernelHash

func CheckStakeKernelHash(t *StakeKernelTemplate) (hashProofOfStake []byte, success bool, err error, minTarget *big.Int)

func CompactToBig

func CompactToBig(compact uint32) *big.Int

CompactToBig converts a compact representation of a whole number N to an unsigned 32-bit number. The representation is similar to IEEE754 floating point numbers.

Like IEEE754 floating point, there are three basic components: the sign, the exponent, and the mantissa. They are broken out as follows:

• the most significant 8 bits represent the unsigned base 256 exponent

• bit 23 (the 24th bit) represents the sign bit

• the least significant 23 bits represent the mantissa

  ------------------------------------------------- | Exponent | Sign | Mantissa | ------------------------------------------------- | 8 bits [31-24] | 1 bit [23] | 23 bits [22-00] | -------------------------------------------------

The formula to calculate N is:

N = (-1^sign) * mantissa * 256^(exponent-3)

This compact form is only used in bitcoin to encode unsigned 256-bit numbers which represent difficulty targets, thus there really is not a need for a sign bit, but it is implemented here to stay consistent with bitcoind.

func CompactToDiff

func CompactToDiff(bits uint32) (diff float32)

func DiffToTarget

func DiffToTarget(diff float32) (target *big.Int)

func IncCompact

func IncCompact(compact uint32) uint32

Types

type CoinStakeSource

type CoinStakeSource struct {
	BlockTime     int64
	StakeModifier uint64
	TxOffset      uint32
	TxTime        int64

	TxSha []byte

	Outputs map[string]*TxOut
}

type StakeKernelTemplate

type StakeKernelTemplate struct {
	BlockFromTime int64
	StakeModifier uint64
	PrevTxOffset  uint32
	PrevTxTime    int64

	PrevTxOutIndex uint32
	PrevTxOutValue int64

	IsProtocolV03 bool
	StakeMinAge   int64
	Bits          uint32
	TxTime        int64
}

type TxOut

type TxOut struct {
	Value    int64
	PkScript []byte
}