Added bloom filter & block filter methods

ethchain/bloom.go

@@ -0,0 +1,47 @@
+package ethchain
+
+type BloomFilter struct {
+	bin []byte
+}
+
+func NewBloomFilter(bin []byte) *BloomFilter {
+	if bin == nil {
+		bin = make([]byte, 255)
+	}
+
+	return &BloomFilter{
+		bin: bin,
+	}
+}
+
+func (self *BloomFilter) Set(addr []byte) {
+	if len(addr) < 8 {
+		chainlogger.Warnf("err: bloom set to small: %x\n", addr)
+
+		return
+	}
+
+	for _, i := range addr[len(addr)-8:] {
+		self.bin[i] = 1
+	}
+}
+
+func (self *BloomFilter) Search(addr []byte) bool {
+	if len(addr) < 8 {
+		chainlogger.Warnf("err: bloom search to small: %x\n", addr)
+
+		return false
+	}
+
+	for _, i := range addr[len(addr)-8:] {
+		if self.bin[i] == 0 {
+			return false
+		}
+	}
+
+	return true
+}
+
+func (self *BloomFilter) Bin() []byte {
+	return self.bin
+}