go-ethereum/pow/ezp/pow.go
2015-01-05 19:53:53 +01:00

94 lines
1.8 KiB
Go

package ezp
import (
"math/big"
"math/rand"
"time"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/ethutil"
"github.com/ethereum/go-ethereum/logger"
"github.com/ethereum/go-ethereum/pow"
"github.com/obscuren/sha3"
)
var powlogger = logger.NewLogger("POW")
type EasyPow struct {
hash *big.Int
HashRate int64
turbo bool
}
func New() *EasyPow {
return &EasyPow{turbo: false}
}
func (pow *EasyPow) GetHashrate() int64 {
return pow.HashRate
}
func (pow *EasyPow) Turbo(on bool) {
pow.turbo = on
}
func (pow *EasyPow) Search(block pow.Block, stop <-chan struct{}) []byte {
r := rand.New(rand.NewSource(time.Now().UnixNano()))
hash := block.HashNoNonce()
diff := block.Difficulty()
i := int64(0)
start := time.Now().UnixNano()
t := time.Now()
for {
select {
case <-stop:
powlogger.Infoln("Breaking from mining")
pow.HashRate = 0
return nil
default:
i++
if time.Since(t) > (1 * time.Second) {
elapsed := time.Now().UnixNano() - start
hashes := ((float64(1e9) / float64(elapsed)) * float64(i)) / 1000
pow.HashRate = int64(hashes)
powlogger.Infoln("Hashing @", pow.HashRate, "khash")
t = time.Now()
}
sha := crypto.Sha3(big.NewInt(r.Int63()).Bytes())
if verify(hash, diff, sha) {
return sha
}
}
if !pow.turbo {
time.Sleep(20 * time.Microsecond)
}
}
return nil
}
func (pow *EasyPow) Verify(block pow.Block) bool {
return Verify(block)
}
func verify(hash []byte, diff *big.Int, nonce []byte) bool {
sha := sha3.NewKeccak256()
d := append(hash, nonce...)
sha.Write(d)
verification := new(big.Int).Div(ethutil.BigPow(2, 256), diff)
res := ethutil.U256(ethutil.BigD(sha.Sum(nil)))
return res.Cmp(verification) <= 0
}
func Verify(block pow.Block) bool {
return verify(block.HashNoNonce(), block.Difficulty(), block.N())
}