path: root/ethchain/bloom9.go

package ethchain

import (
    "math/big"

    "github.com/ethereum/go-ethereum/vm"
)

func CreateBloom(txs Transactions) []byte {
    bin := new(big.Int)
    for _, tx := range txs {
        bin.Or(bin, LogsBloom(tx.logs))
    }

    return bin.Bytes()
}

func LogsBloom(logs []vm.Log) *big.Int {
    bin := new(big.Int)
    for _, log := range logs {
        data := [][]byte{log.Address}
        for _, topic := range log.Topics {
            data = append(data, topic)
        }
        data = append(data, log.Data)

        for _, b := range data {
            bin.Or(bin, bloom9(b))
        }
    }

    return bin
}

func bloom9(b []byte) *big.Int {
    r := new(big.Int)
    for _, i := range []int{0, 2, 4} {
        t := big.NewInt(1)

        //r |= 1 << (uint64(b[i+1]) + 256*(uint64(b[i])&1))
        r.Or(r, t.Rsh(t, uint(b[i+1])+256*(uint(b[i])&1)))
    }

    return r
}