1 files changed, 418 insertions, 0 deletions
diff --git a/ethutil/rlp.go b/ethutil/rlp.go
new file mode 100644
index 000000000..0f88933b3
--- /dev/null
+++ b/ethutil/rlp.go
@@ -0,0 +1,418 @@
+package ethutil
+
+import (
+	"bytes"
+	_ "encoding/binary"
+	"fmt"
+	_ "log"
+	_ "math"
+	"math/big"
+	"reflect"
+)
+
+///////////////////////////////////////
+type EthEncoder interface {
+	EncodeData(rlpData interface{}) []byte
+}
+type EthDecoder interface {
+	Get(idx int) *RlpValue
+}
+
+//////////////////////////////////////
+
+type RlpEncoder struct {
+	rlpData []byte
+}
+
+func NewRlpEncoder() *RlpEncoder {
+	encoder := &RlpEncoder{}
+
+	return encoder
+}
+func (coder *RlpEncoder) EncodeData(rlpData interface{}) []byte {
+	return Encode(rlpData)
+}
+
+// Data rlpValueutes are returned by the rlp decoder. The data rlpValueutes represents
+// one item within the rlp data structure. It's responsible for all the casting
+// It always returns something rlpValueid
+type RlpValue struct {
+	Value interface{}
+	kind  reflect.Value
+}
+
+func (rlpValue *RlpValue) String() string {
+	return fmt.Sprintf("%q", rlpValue.Value)
+}
+
+func Conv(rlpValue interface{}) *RlpValue {
+	return &RlpValue{Value: rlpValue, kind: reflect.ValueOf(rlpValue)}
+}
+
+func NewRlpValue(rlpValue interface{}) *RlpValue {
+	return &RlpValue{Value: rlpValue}
+}
+
+func (rlpValue *RlpValue) Type() reflect.Kind {
+	return reflect.TypeOf(rlpValue.Value).Kind()
+}
+
+func (rlpValue *RlpValue) IsNil() bool {
+	return rlpValue.Value == nil
+}
+
+func (rlpValue *RlpValue) Length() int {
+	//return rlpValue.kind.Len()
+	if data, ok := rlpValue.Value.([]interface{}); ok {
+		return len(data)
+	}
+
+	return 0
+}
+
+func (rlpValue *RlpValue) AsRaw() interface{} {
+	return rlpValue.Value
+}
+
+func (rlpValue *RlpValue) AsUint() uint64 {
+	if Value, ok := rlpValue.Value.(uint8); ok {
+		return uint64(Value)
+	} else if Value, ok := rlpValue.Value.(uint16); ok {
+		return uint64(Value)
+	} else if Value, ok := rlpValue.Value.(uint32); ok {
+		return uint64(Value)
+	} else if Value, ok := rlpValue.Value.(uint64); ok {
+		return Value
+	}
+
+	return 0
+}
+
+func (rlpValue *RlpValue) AsByte() byte {
+	if Value, ok := rlpValue.Value.(byte); ok {
+		return Value
+	}
+
+	return 0x0
+}
+
+func (rlpValue *RlpValue) AsBigInt() *big.Int {
+	if a, ok := rlpValue.Value.([]byte); ok {
+		b := new(big.Int)
+		b.SetBytes(a)
+		return b
+	}
+
+	return big.NewInt(0)
+}
+
+func (rlpValue *RlpValue) AsString() string {
+	if a, ok := rlpValue.Value.([]byte); ok {
+		return string(a)
+	} else if a, ok := rlpValue.Value.(string); ok {
+		return a
+	} else {
+		//panic(fmt.Sprintf("not string %T: %v", rlpValue.Value, rlpValue.Value))
+	}
+
+	return ""
+}
+
+func (rlpValue *RlpValue) AsBytes() []byte {
+	if a, ok := rlpValue.Value.([]byte); ok {
+		return a
+	}
+
+	return make([]byte, 0)
+}
+
+func (rlpValue *RlpValue) AsSlice() []interface{} {
+	if d, ok := rlpValue.Value.([]interface{}); ok {
+		return d
+	}
+
+	return []interface{}{}
+}
+
+func (rlpValue *RlpValue) AsSliceFrom(from int) *RlpValue {
+	slice := rlpValue.AsSlice()
+
+	return NewRlpValue(slice[from:])
+}
+
+func (rlpValue *RlpValue) AsSliceTo(to int) *RlpValue {
+	slice := rlpValue.AsSlice()
+
+	return NewRlpValue(slice[:to])
+}
+
+func (rlpValue *RlpValue) AsSliceFromTo(from, to int) *RlpValue {
+	slice := rlpValue.AsSlice()
+
+	return NewRlpValue(slice[from:to])
+}
+
+// Threat the rlpValueute as a slice
+func (rlpValue *RlpValue) Get(idx int) *RlpValue {
+	if d, ok := rlpValue.Value.([]interface{}); ok {
+		// Guard for oob
+		if len(d) <= idx {
+			return NewRlpValue(nil)
+		}
+
+		if idx < 0 {
+			panic("negative idx for Rlp Get")
+		}
+
+		return NewRlpValue(d[idx])
+	}
+
+	// If this wasn't a slice you probably shouldn't be using this function
+	return NewRlpValue(nil)
+}
+
+func (rlpValue *RlpValue) Cmp(o *RlpValue) bool {
+	return reflect.DeepEqual(rlpValue.Value, o.Value)
+}
+
+func (rlpValue *RlpValue) Encode() []byte {
+	return Encode(rlpValue.Value)
+}
+
+func NewRlpValueFromBytes(rlpData []byte) *RlpValue {
+	if len(rlpData) != 0 {
+		data, _ := Decode(rlpData, 0)
+		return NewRlpValue(data)
+	}
+
+	return NewRlpValue(nil)
+}
+
+// RlpValue value setters
+// An empty rlp value is always a list
+func EmptyRlpValue() *RlpValue {
+	return NewRlpValue([]interface{}{})
+}
+
+func (rlpValue *RlpValue) AppendList() *RlpValue {
+	list := EmptyRlpValue()
+	rlpValue.Value = append(rlpValue.AsSlice(), list)
+
+	return list
+}
+
+func (rlpValue *RlpValue) Append(v interface{}) *RlpValue {
+	rlpValue.Value = append(rlpValue.AsSlice(), v)
+
+	return rlpValue
+}
+
+/*
+func FromBin(data []byte) uint64 {
+	if len(data) == 0 {
+		return 0
+	}
+
+	return FromBin(data[:len(data)-1])*256 + uint64(data[len(data)-1])
+}
+*/
+
+const (
+	RlpEmptyList = 0x80
+	RlpEmptyStr  = 0x40
+)
+
+func Char(c []byte) int {
+	if len(c) > 0 {
+		return int(c[0])
+	}
+
+	return 0
+}
+
+func DecodeWithReader(reader *bytes.Buffer) interface{} {
+	var slice []interface{}
+
+	// Read the next byte
+	char := Char(reader.Next(1))
+	switch {
+	case char == 0:
+		return nil
+	case char <= 0x7c:
+		return char
+
+	case char <= 0xb7:
+		return reader.Next(int(char - 0x80))
+
+	case char <= 0xbf:
+		buff := bytes.NewReader(reader.Next(int(char - 0xb8)))
+		length := ReadVarint(buff)
+
+		return reader.Next(int(length))
+
+	case char <= 0xf7:
+		length := int(char - 0xc0)
+		for i := 0; i < length; i++ {
+			obj := DecodeWithReader(reader)
+			if obj != nil {
+				slice = append(slice, obj)
+			} else {
+				break
+			}
+		}
+
+		return slice
+
+	}
+
+	return slice
+}
+
+// TODO Use a bytes.Buffer instead of a raw byte slice.
+// Cleaner code, and use draining instead of seeking the next bytes to read
+func Decode(data []byte, pos uint64) (interface{}, uint64) {
+	/*
+		if pos > uint64(len(data)-1) {
+			log.Println(data)
+			log.Panicf("index out of range %d for data %q, l = %d", pos, data, len(data))
+		}
+	*/
+
+	var slice []interface{}
+	char := int(data[pos])
+	switch {
+	case char <= 0x7f:
+		return data[pos], pos + 1
+
+	case char <= 0xb7:
+		b := uint64(data[pos]) - 0x80
+
+		return data[pos+1 : pos+1+b], pos + 1 + b
+
+	case char <= 0xbf:
+		b := uint64(data[pos]) - 0xb7
+
+		b2 := ReadVarint(bytes.NewReader(data[pos+1 : pos+1+b]))
+
+		return data[pos+1+b : pos+1+b+b2], pos + 1 + b + b2
+
+	case char <= 0xf7:
+		b := uint64(data[pos]) - 0xc0
+		prevPos := pos
+		pos++
+		for i := uint64(0); i < b; {
+			var obj interface{}
+
+			// Get the next item in the data list and append it
+			obj, prevPos = Decode(data, pos)
+			slice = append(slice, obj)
+
+			// Increment i by the amount bytes read in the previous
+			// read
+			i += (prevPos - pos)
+			pos = prevPos
+		}
+		return slice, pos
+
+	case char <= 0xff:
+		l := uint64(data[pos]) - 0xf7
+		//b := BigD(data[pos+1 : pos+1+l]).Uint64()
+		b := ReadVarint(bytes.NewReader(data[pos+1 : pos+1+l]))
+
+		pos = pos + l + 1
+
+		prevPos := b
+		for i := uint64(0); i < uint64(b); {
+			var obj interface{}
+
+			obj, prevPos = Decode(data, pos)
+			slice = append(slice, obj)
+
+			i += (prevPos - pos)
+			pos = prevPos
+		}
+		return slice, pos
+
+	default:
+		panic(fmt.Sprintf("byte not supported: %q", char))
+	}
+
+	return slice, 0
+}
+
+var (
+	directRlp = big.NewInt(0x7f)
+	numberRlp = big.NewInt(0xb7)
+	zeroRlp   = big.NewInt(0x0)
+)
+
+func Encode(object interface{}) []byte {
+	var buff bytes.Buffer
+
+	if object != nil {
+		switch t := object.(type) {
+		case *RlpValue:
+			buff.Write(Encode(t.AsRaw()))
+		// Code dup :-/
+		case int:
+			buff.Write(Encode(big.NewInt(int64(t))))
+		case uint:
+			buff.Write(Encode(big.NewInt(int64(t))))
+		case int8:
+			buff.Write(Encode(big.NewInt(int64(t))))
+		case int16:
+			buff.Write(Encode(big.NewInt(int64(t))))
+		case int32:
+			buff.Write(Encode(big.NewInt(int64(t))))
+		case int64:
+			buff.Write(Encode(big.NewInt(t)))
+		case uint16:
+			buff.Write(Encode(big.NewInt(int64(t))))
+		case uint32:
+			buff.Write(Encode(big.NewInt(int64(t))))
+		case uint64:
+			buff.Write(Encode(big.NewInt(int64(t))))
+		case byte:
+			buff.Write(Encode(big.NewInt(int64(t))))
+		case *big.Int:
+			buff.Write(Encode(t.Bytes()))
+		case []byte:
+			if len(t) == 1 && t[0] <= 0x7f {
+				buff.Write(t)
+			} else if len(t) < 56 {
+				buff.WriteByte(byte(len(t) + 0x80))
+				buff.Write(t)
+			} else {
+				b := big.NewInt(int64(len(t)))
+				buff.WriteByte(byte(len(b.Bytes()) + 0xb7))
+				buff.Write(b.Bytes())
+				buff.Write(t)
+			}
+		case string:
+			buff.Write(Encode([]byte(t)))
+		case []interface{}:
+			// Inline function for writing the slice header
+			WriteSliceHeader := func(length int) {
+				if length < 56 {
+					buff.WriteByte(byte(length + 0xc0))
+				} else {
+					b := big.NewInt(int64(length))
+					buff.WriteByte(byte(len(b.Bytes()) + 0xf7))
+					buff.Write(b.Bytes())
+				}
+			}
+
+			var b bytes.Buffer
+			for _, val := range t {
+				b.Write(Encode(val))
+			}
+			WriteSliceHeader(len(b.Bytes()))
+			buff.Write(b.Bytes())
+		}
+	} else {
+		// Empty list for nil
+		buff.WriteByte(0xc0)
+	}
+
+	return buff.Bytes()
+}