Golang common.BigPow函數代碼示例

func (dag *Dagger) Search(hash, diff *big.Int) (uint64, []byte) {
	// TODO fix multi threading. Somehow it results in the wrong nonce
	amountOfRoutines := 1

	dag.hash = hash

	obj := common.BigPow(2, 256)
	obj = obj.Div(obj, diff)

	Found = false
	resChan := make(chan int64, 3)
	var res int64

	for k := 0; k < amountOfRoutines; k++ {
		go dag.Find(obj, resChan)

		// Wait for each go routine to finish
	}
	for k := 0; k < amountOfRoutines; k++ {
		// Get the result from the channel. 0 = quit
		if r := <-resChan; r != 0 {
			res = r
		}
	}

	return uint64(res), nil
}

func (dag *Dagger) Eval(N *big.Int) *big.Int {
	pow := common.BigPow(2, 26)
	dag.xn = pow.Div(N, pow)

	sha := sha3.NewKeccak256()
	sha.Reset()
	ret := new(big.Int)

	for k := 0; k < 4; k++ {
		d := sha3.NewKeccak256()
		b := new(big.Int)

		d.Reset()
		d.Write(dag.hash.Bytes())
		d.Write(dag.xn.Bytes())
		d.Write(N.Bytes())
		d.Write(big.NewInt(int64(k)).Bytes())

		b.SetBytes(Sum(d))
		pk := (b.Uint64() & 0x1ffffff)

		sha.Write(dag.Node(9, pk).Bytes())
	}

	return ret.SetBytes(Sum(sha))
}

// Block creation & chain handling
func (bc *ChainManager) NewBlock(coinbase common.Address) *types.Block {
	bc.mu.RLock()
	defer bc.mu.RUnlock()

	var (
		root       common.Hash
		parentHash common.Hash
	)

	if bc.currentBlock != nil {
		root = bc.currentBlock.Header().Root
		parentHash = bc.lastBlockHash
	}

	block := types.NewBlock(
		parentHash,
		coinbase,
		root,
		common.BigPow(2, 32),
		0,
		nil)
	block.SetUncles(nil)
	block.SetTransactions(nil)
	block.SetReceipts(nil)

	parent := bc.currentBlock
	if parent != nil {
		header := block.Header()
		header.Difficulty = CalcDifficulty(block.Header(), parent.Header())
		header.Number = new(big.Int).Add(parent.Header().Number, common.Big1)
		header.GasLimit = CalcGasLimit(parent)
	}

	return block
}

func (dag *Dagger) Verify(hash, diff, nonce *big.Int) bool {
	dag.hash = hash

	obj := common.BigPow(2, 256)
	obj = obj.Div(obj, diff)

	return dag.Eval(nonce).Cmp(obj) < 0
}

func BenchmarkDaggerSearch(b *testing.B) {
	hash := big.NewInt(0)
	diff := common.BigPow(2, 36)
	o := big.NewInt(0) // nonce doesn't matter. We're only testing against speed, not validity

	// Reset timer so the big generation isn't included in the benchmark
	b.ResetTimer()
	// Validate
	DaggerVerify(hash, diff, o)
}

func verify(hash common.Hash, diff *big.Int, nonce uint64) bool {
	sha := sha3.NewKeccak256()
	n := make([]byte, 8)
	binary.PutUvarint(n, nonce)
	sha.Write(n)
	sha.Write(hash[:])
	verification := new(big.Int).Div(common.BigPow(2, 256), diff)
	res := common.BigD(sha.Sum(nil))
	return res.Cmp(verification) <= 0
}

// block time is fixed at 10 seconds
func newBlockFromParent(addr common.Address, parent *types.Block) *types.Block {
	block := types.NewBlock(parent.Hash(), addr, parent.Root(), common.BigPow(2, 32), 0, nil)
	block.SetUncles(nil)
	block.SetTransactions(nil)
	block.SetReceipts(nil)

	header := block.Header()
	header.Difficulty = CalcDifficulty(block.Header(), parent.Header())
	header.Number = new(big.Int).Add(parent.Header().Number, common.Big1)
	header.Time = parent.Header().Time + 10
	header.GasLimit = CalcGasLimit(parent)

	block.Td = parent.Td

	return block
}

var pendingBlockDifficulty *big.Int

var invalidRequest = `{
  "id":64,
  "jsonrpc": "2.0",
  "result": false,
  "error": "invalid request"
}`

var okRequest = `{
  "id":64,
  "jsonrpc": "2.0",
  "result": true
}`

var pow256 = common.BigPow(2, 256)

var hasher = ethash.New()

var secret = "CHANGETHIS"
var poolPort = "5082"
var ethereumPort = "8545" //8545 = geth, 8080 = eth (requires dev branch when using eth client)

var logInfo *log.Logger
var logError *log.Logger

type ResponseArray struct {
	Id      int           `json:"id"`
	Jsonrpc string        `json:"jsonrpc"`
	Result  []interface{} `json:"result"`
}

}
func BenchmarkInsertChain_ring200_diskdb(b *testing.B) {
	benchInsertChain(b, true, genTxRing(200))
}
func BenchmarkInsertChain_ring1000_memdb(b *testing.B) {
	benchInsertChain(b, false, genTxRing(1000))
}
func BenchmarkInsertChain_ring1000_diskdb(b *testing.B) {
	benchInsertChain(b, true, genTxRing(1000))
}

var (
	// This is the content of the genesis block used by the benchmarks.
	benchRootKey, _ = crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")
	benchRootAddr   = crypto.PubkeyToAddress(benchRootKey.PublicKey)
	benchRootFunds  = common.BigPow(2, 100)
)

// genValueTx returns a block generator that includes a single
// value-transfer transaction with n bytes of extra data in each
// block.
func genValueTx(nbytes int) func(int, *BlockGen) {
	return func(i int, gen *BlockGen) {
		toaddr := common.Address{}
		data := make([]byte, nbytes)
		gas := IntrinsicGas(data)
		tx, _ := types.NewTransaction(gen.TxNonce(benchRootAddr), toaddr, big.NewInt(1), gas, nil, data).SignECDSA(benchRootKey)
		gen.AddTx(tx)
	}
}

// Global Debug flag indicating Debug VM (full logging)
var Debug bool

var GenerateStructLogs bool = false

// Type is the VM type accepted by **NewVm**
type Type byte

const (
	StdVmTy Type = iota // Default standard VM
	JitVmTy             // LLVM JIT VM
	MaxVmTy
)

var (
	Pow256 = common.BigPow(2, 256) // Pow256 is 2**256

	U256 = common.U256 // Shortcut to common.U256
	S256 = common.S256 // Shortcut to common.S256

	Zero = common.Big0 // Shortcut to common.Big0
	One  = common.Big1 // Shortcut to common.Big1

	max = big.NewInt(math.MaxInt64) // Maximum 64 bit integer
)

// NewVm returns a new VM based on the Environment
func NewVm(env Environment) VirtualMachine {
	switch env.VmType() {
	case JitVmTy:
		return NewJitVm(env)