initial commit of p2p package

1 files changed, 75 insertions, 0 deletions

diff --git a/p2p/message.go b/p2p/message.go
new file mode 100644
index 000000000..4886eaa1f
--- /dev/null
+++ b/p2p/message.go
@@ -0,0 +1,75 @@
+package p2p
+
+import (
+	// "fmt"
+	"github.com/ethereum/eth-go/ethutil"
+)
+
+type MsgCode uint8
+
+type Msg struct {
+	code    MsgCode // this is the raw code as per adaptive msg code scheme
+	data    *ethutil.Value
+	encoded []byte
+}
+
+func (self *Msg) Code() MsgCode {
+	return self.code
+}
+
+func (self *Msg) Data() *ethutil.Value {
+	return self.data
+}
+
+func NewMsg(code MsgCode, params ...interface{}) (msg *Msg, err error) {
+
+	// // data := [][]interface{}{}
+	// data := []interface{}{}
+	// for _, value := range params {
+	// 	if encodable, ok := value.(ethutil.RlpEncodeDecode); ok {
+	// 		data = append(data, encodable.RlpValue())
+	// 	} else if raw, ok := value.([]interface{}); ok {
+	// 		data = append(data, raw)
+	// 	} else {
+	// 		// data = append(data, interface{}(raw))
+	// 		err = fmt.Errorf("Unable to encode object of type %T", value)
+	// 		return
+	// 	}
+	// }
+	return &Msg{
+		code: code,
+		data: ethutil.NewValue(interface{}(params)),
+	}, nil
+}
+
+func NewMsgFromBytes(encoded []byte) (msg *Msg, err error) {
+	value := ethutil.NewValueFromBytes(encoded)
+	// Type of message
+	code := value.Get(0).Uint()
+	// Actual data
+	data := value.SliceFrom(1)
+
+	msg = &Msg{
+		code: MsgCode(code),
+		data: data,
+		// data:    ethutil.NewValue(data),
+		encoded: encoded,
+	}
+	return
+}
+
+func (self *Msg) Decode(offset MsgCode) {
+	self.code = self.code - offset
+}
+
+// encode takes an offset argument to implement adaptive message coding
+// the encoded message is memoized to make msgs relayed to several peers more efficient
+func (self *Msg) Encode(offset MsgCode) (res []byte) {
+	if len(self.encoded) == 0 {
+		res = ethutil.NewValue(append([]interface{}{byte(self.code + offset)}, self.data.Slice()...)).Encode()
+		self.encoded = res
+	} else {
+		res = self.encoded
+	}
+	return
+}