Moved ethchain to chain

chain/bloom9.go

@@ -0,0 +1,55 @@
+package chain
+
+import (
+	"math/big"
+
+	"github.com/ethereum/go-ethereum/ethstate"
+	"github.com/ethereum/go-ethereum/ethutil"
+)
+
+func CreateBloom(block *Block) []byte {
+	bin := new(big.Int)
+	bin.Or(bin, bloom9(block.Coinbase))
+	for _, receipt := range block.Receipts() {
+		bin.Or(bin, LogsBloom(receipt.logs))
+	}
+
+	return bin.Bytes()
+}
+
+func LogsBloom(logs ethstate.Logs) *big.Int {
+	bin := new(big.Int)
+	for _, log := range logs {
+		data := [][]byte{log.Address}
+		for _, topic := range log.Topics {
+			data = append(data, topic)
+		}
+
+		if log.Data != nil {
+			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.Or(r, t.Lsh(t, uint(b[i+1])+256*(uint(b[i])&1)))
+	}
+
+	return r
+}
+
+func BloomLookup(bin, topic []byte) bool {
+	bloom := ethutil.BigD(bin)
+	cmp := bloom9(topic)
+
+	return bloom.And(bloom, cmp).Cmp(cmp) == 0
+}