Merge pull request #203 from fjl/rlp-fixes

RLP: remove signed integer support and other fixes
This commit is contained in:
Jeffrey Wilcke 2014-12-10 00:06:17 +01:00
commit ce0c4e5d86
3 changed files with 145 additions and 147 deletions

View File

@ -54,7 +54,7 @@ type Decoder interface {
// To decode into a Go string, the input must be an RLP string. The
// bytes are taken as-is and will not necessarily be valid UTF-8.
//
// To decode into an integer type, the input must also be an RLP
// To decode into an unsigned integer type, the input must also be an RLP
// string. The bytes are interpreted as a big endian representation of
// the integer. If the RLP string is larger than the bit size of the
// type, Decode will return an error. Decode also supports *big.Int.
@ -66,8 +66,9 @@ type Decoder interface {
// []interface{}, for RLP lists
// []byte, for RLP strings
//
// Non-empty interface types are not supported, nor are bool, float32,
// float64, maps, channel types and functions.
// Non-empty interface types are not supported, nor are booleans,
// signed integers, floating point numbers, maps, channels and
// functions.
func Decode(r io.Reader, val interface{}) error {
return NewStream(r).Decode(val)
}
@ -81,37 +82,58 @@ func (err decodeError) Error() string {
return fmt.Sprintf("rlp: %s for %v", err.msg, err.typ)
}
func makeNumDecoder(typ reflect.Type) decoder {
kind := typ.Kind()
switch {
case kind <= reflect.Int64:
return decodeInt
case kind <= reflect.Uint64:
return decodeUint
default:
panic("fallthrough")
}
}
func decodeInt(s *Stream, val reflect.Value) error {
typ := val.Type()
num, err := s.uint(typ.Bits())
if err == errUintOverflow {
func wrapStreamError(err error, typ reflect.Type) error {
switch err {
case ErrExpectedList:
return decodeError{"expected input list", typ}
case ErrExpectedString:
return decodeError{"expected input string or byte", typ}
case errUintOverflow:
return decodeError{"input string too long", typ}
} else if err != nil {
case errNotAtEOL:
return decodeError{"input list has too many elements", typ}
}
return err
}
val.SetInt(int64(num))
return nil
var (
decoderInterface = reflect.TypeOf(new(Decoder)).Elem()
bigInt = reflect.TypeOf(big.Int{})
)
func makeDecoder(typ reflect.Type) (dec decoder, err error) {
kind := typ.Kind()
switch {
case typ.Implements(decoderInterface):
return decodeDecoder, nil
case kind != reflect.Ptr && reflect.PtrTo(typ).Implements(decoderInterface):
return decodeDecoderNoPtr, nil
case typ.AssignableTo(reflect.PtrTo(bigInt)):
return decodeBigInt, nil
case typ.AssignableTo(bigInt):
return decodeBigIntNoPtr, nil
case isUint(kind):
return decodeUint, nil
case kind == reflect.String:
return decodeString, nil
case kind == reflect.Slice || kind == reflect.Array:
return makeListDecoder(typ)
case kind == reflect.Struct:
return makeStructDecoder(typ)
case kind == reflect.Ptr:
return makePtrDecoder(typ)
case kind == reflect.Interface && typ.NumMethod() == 0:
return decodeInterface, nil
default:
return nil, fmt.Errorf("rlp: type %v is not RLP-serializable", typ)
}
}
func decodeUint(s *Stream, val reflect.Value) error {
typ := val.Type()
num, err := s.uint(typ.Bits())
if err == errUintOverflow {
return decodeError{"input string too big", typ}
} else if err != nil {
return err
if err != nil {
return wrapStreamError(err, val.Type())
}
val.SetUint(num)
return nil
@ -120,7 +142,7 @@ func decodeUint(s *Stream, val reflect.Value) error {
func decodeString(s *Stream, val reflect.Value) error {
b, err := s.Bytes()
if err != nil {
return err
return wrapStreamError(err, val.Type())
}
val.SetString(string(b))
return nil
@ -133,7 +155,7 @@ func decodeBigIntNoPtr(s *Stream, val reflect.Value) error {
func decodeBigInt(s *Stream, val reflect.Value) error {
b, err := s.Bytes()
if err != nil {
return err
return wrapStreamError(err, val.Type())
}
i := val.Interface().(*big.Int)
if i == nil {
@ -144,8 +166,6 @@ func decodeBigInt(s *Stream, val reflect.Value) error {
return nil
}
const maxInt = int(^uint(0) >> 1)
func makeListDecoder(typ reflect.Type) (decoder, error) {
etype := typ.Elem()
if etype.Kind() == reflect.Uint8 && !reflect.PtrTo(etype).Implements(decoderInterface) {
@ -159,42 +179,29 @@ func makeListDecoder(typ reflect.Type) (decoder, error) {
if err != nil {
return nil, err
}
var maxLen = maxInt
if typ.Kind() == reflect.Array {
maxLen = typ.Len()
return func(s *Stream, val reflect.Value) error {
return decodeListArray(s, val, etypeinfo.decoder)
}, nil
}
dec := func(s *Stream, val reflect.Value) error {
return decodeList(s, val, etypeinfo.decoder, maxLen)
}
return dec, nil
return func(s *Stream, val reflect.Value) error {
return decodeListSlice(s, val, etypeinfo.decoder)
}, nil
}
// decodeList decodes RLP list elements into slices and arrays.
//
// The approach here is stolen from package json, although we differ
// in the semantics for arrays. package json discards remaining
// elements that would not fit into the array. We generate an error in
// this case because we'd be losing information.
func decodeList(s *Stream, val reflect.Value, elemdec decoder, maxelem int) error {
func decodeListSlice(s *Stream, val reflect.Value, elemdec decoder) error {
size, err := s.List()
if err != nil {
return err
return wrapStreamError(err, val.Type())
}
if size == 0 {
if val.Kind() == reflect.Slice {
val.Set(reflect.MakeSlice(val.Type(), 0, 0))
} else {
zero(val, 0)
}
return s.ListEnd()
}
i := 0
for {
if i > maxelem {
return decodeError{"input list has too many elements", val.Type()}
}
if val.Kind() == reflect.Slice {
for ; ; i++ {
// grow slice if necessary
if i >= val.Cap() {
newcap := val.Cap() + val.Cap()/2
@ -208,33 +215,55 @@ func decodeList(s *Stream, val reflect.Value, elemdec decoder, maxelem int) erro
if i >= val.Len() {
val.SetLen(i + 1)
}
}
// decode into element
if err := elemdec(s, val.Index(i)); err == EOL {
break
} else if err != nil {
return err
}
i++
}
if i < val.Len() {
if val.Kind() == reflect.Array {
// zero the rest of the array.
zero(val, i)
} else {
val.SetLen(i)
}
}
return s.ListEnd()
}
func decodeListArray(s *Stream, val reflect.Value, elemdec decoder) error {
size, err := s.List()
if err != nil {
return err
}
if size == 0 {
zero(val, 0)
return s.ListEnd()
}
// The approach here is stolen from package json, although we differ
// in the semantics for arrays. package json discards remaining
// elements that would not fit into the array. We generate an error in
// this case because we'd be losing information.
vlen := val.Len()
i := 0
for ; i < vlen; i++ {
if err := elemdec(s, val.Index(i)); err == EOL {
break
} else if err != nil {
return err
}
}
if i < vlen {
zero(val, i)
}
return wrapStreamError(s.ListEnd(), val.Type())
}
func decodeByteSlice(s *Stream, val reflect.Value) error {
kind, _, err := s.Kind()
if err != nil {
return err
}
if kind == List {
return decodeList(s, val, decodeUint, maxInt)
return decodeListSlice(s, val, decodeUint)
}
b, err := s.Bytes()
if err == nil {
@ -251,14 +280,14 @@ func decodeByteArray(s *Stream, val reflect.Value) error {
switch kind {
case Byte:
if val.Len() == 0 {
return decodeError{"input string too big", val.Type()}
return decodeError{"input string too long", val.Type()}
}
bv, _ := s.Uint()
val.Index(0).SetUint(bv)
zero(val, 1)
case String:
if uint64(val.Len()) < size {
return decodeError{"input string too big", val.Type()}
return decodeError{"input string too long", val.Type()}
}
slice := val.Slice(0, int(size)).Interface().([]byte)
if err := s.readFull(slice); err != nil {
@ -266,14 +295,15 @@ func decodeByteArray(s *Stream, val reflect.Value) error {
}
zero(val, int(size))
case List:
return decodeList(s, val, decodeUint, val.Len())
return decodeListArray(s, val, decodeUint)
}
return nil
}
func zero(val reflect.Value, start int) {
z := reflect.Zero(val.Type().Elem())
for i := start; i < val.Len(); i++ {
end := val.Len()
for i := start; i < end; i++ {
val.Index(i).Set(z)
}
}
@ -296,7 +326,7 @@ func makeStructDecoder(typ reflect.Type) (decoder, error) {
}
dec := func(s *Stream, val reflect.Value) (err error) {
if _, err = s.List(); err != nil {
return err
return wrapStreamError(err, typ)
}
for _, f := range fields {
err = f.info.decoder(s, val.Field(f.index))
@ -307,10 +337,7 @@ func makeStructDecoder(typ reflect.Type) (decoder, error) {
return err
}
}
if err = s.ListEnd(); err == errNotAtEOL {
err = decodeError{"input list has too many elements", typ}
}
return err
return wrapStreamError(s.ListEnd(), typ)
}
return dec, nil
}
@ -348,7 +375,7 @@ func decodeInterface(s *Stream, val reflect.Value) error {
}
if kind == List {
slice := reflect.New(ifsliceType).Elem()
if err := decodeList(s, slice, decodeInterface, maxInt); err != nil {
if err := decodeListSlice(s, slice, decodeInterface); err != nil {
return err
}
val.Set(slice)

View File

@ -171,7 +171,7 @@ func TestDecodeErrors(t *testing.T) {
t.Errorf("Decode(r, new(chan bool)) error mismatch, got %q, want %q", err, expectErr)
}
if err := Decode(r, new(int)); err != io.EOF {
if err := Decode(r, new(uint)); err != io.EOF {
t.Errorf("Decode(r, new(int)) error mismatch, got %q, want %q", err, io.EOF)
}
}
@ -184,12 +184,12 @@ type decodeTest struct {
}
type simplestruct struct {
A int
A uint
B string
}
type recstruct struct {
I int
I uint
Child *recstruct
}
@ -202,7 +202,7 @@ var (
var (
sharedByteArray [5]byte
sharedPtr = new(*int)
sharedPtr = new(*uint)
)
var decodeTests = []decodeTest{
@ -213,17 +213,17 @@ var decodeTests = []decodeTest{
{input: "820505", ptr: new(uint32), value: uint32(0x0505)},
{input: "83050505", ptr: new(uint32), value: uint32(0x050505)},
{input: "8405050505", ptr: new(uint32), value: uint32(0x05050505)},
{input: "850505050505", ptr: new(uint32), error: "rlp: input string too big for uint32"},
{input: "C0", ptr: new(uint32), error: ErrExpectedString.Error()},
{input: "850505050505", ptr: new(uint32), error: "rlp: input string too long for uint32"},
{input: "C0", ptr: new(uint32), error: "rlp: expected input string or byte for uint32"},
// slices
{input: "C0", ptr: new([]int), value: []int{}},
{input: "C80102030405060708", ptr: new([]int), value: []int{1, 2, 3, 4, 5, 6, 7, 8}},
{input: "C0", ptr: new([]uint), value: []uint{}},
{input: "C80102030405060708", ptr: new([]uint), value: []uint{1, 2, 3, 4, 5, 6, 7, 8}},
// arrays
{input: "C0", ptr: new([5]int), value: [5]int{}},
{input: "C50102030405", ptr: new([5]int), value: [5]int{1, 2, 3, 4, 5}},
{input: "C6010203040506", ptr: new([5]int), error: "rlp: input list has too many elements for [5]int"},
{input: "C0", ptr: new([5]uint), value: [5]uint{}},
{input: "C50102030405", ptr: new([5]uint), value: [5]uint{1, 2, 3, 4, 5}},
{input: "C6010203040506", ptr: new([5]uint), error: "rlp: input list has too many elements for [5]uint"},
// byte slices
{input: "01", ptr: new([]byte), value: []byte{1}},
@ -231,7 +231,7 @@ var decodeTests = []decodeTest{
{input: "8D6162636465666768696A6B6C6D", ptr: new([]byte), value: []byte("abcdefghijklm")},
{input: "C0", ptr: new([]byte), value: []byte{}},
{input: "C3010203", ptr: new([]byte), value: []byte{1, 2, 3}},
{input: "C3820102", ptr: new([]byte), error: "rlp: input string too big for uint8"},
{input: "C3820102", ptr: new([]byte), error: "rlp: input string too long for uint8"},
// byte arrays
{input: "01", ptr: new([5]byte), value: [5]byte{1}},
@ -239,8 +239,8 @@ var decodeTests = []decodeTest{
{input: "850102030405", ptr: new([5]byte), value: [5]byte{1, 2, 3, 4, 5}},
{input: "C0", ptr: new([5]byte), value: [5]byte{}},
{input: "C3010203", ptr: new([5]byte), value: [5]byte{1, 2, 3, 0, 0}},
{input: "C3820102", ptr: new([5]byte), error: "rlp: input string too big for uint8"},
{input: "86010203040506", ptr: new([5]byte), error: "rlp: input string too big for [5]uint8"},
{input: "C3820102", ptr: new([5]byte), error: "rlp: input string too long for uint8"},
{input: "86010203040506", ptr: new([5]byte), error: "rlp: input string too long for [5]uint8"},
{input: "850101", ptr: new([5]byte), error: io.ErrUnexpectedEOF.Error()},
// byte array reuse (should be zeroed)
@ -254,19 +254,19 @@ var decodeTests = []decodeTest{
// zero sized byte arrays
{input: "80", ptr: new([0]byte), value: [0]byte{}},
{input: "C0", ptr: new([0]byte), value: [0]byte{}},
{input: "01", ptr: new([0]byte), error: "rlp: input string too big for [0]uint8"},
{input: "8101", ptr: new([0]byte), error: "rlp: input string too big for [0]uint8"},
{input: "01", ptr: new([0]byte), error: "rlp: input string too long for [0]uint8"},
{input: "8101", ptr: new([0]byte), error: "rlp: input string too long for [0]uint8"},
// strings
{input: "00", ptr: new(string), value: "\000"},
{input: "8D6162636465666768696A6B6C6D", ptr: new(string), value: "abcdefghijklm"},
{input: "C0", ptr: new(string), error: ErrExpectedString.Error()},
{input: "C0", ptr: new(string), error: "rlp: expected input string or byte for string"},
// big ints
{input: "01", ptr: new(*big.Int), value: big.NewInt(1)},
{input: "89FFFFFFFFFFFFFFFFFF", ptr: new(*big.Int), value: veryBigInt},
{input: "10", ptr: new(big.Int), value: *big.NewInt(16)}, // non-pointer also works
{input: "C0", ptr: new(*big.Int), error: ErrExpectedString.Error()},
{input: "C0", ptr: new(*big.Int), error: "rlp: expected input string or byte for *big.Int"},
// structs
{input: "C0", ptr: new(simplestruct), value: simplestruct{0, ""}},
@ -280,17 +280,17 @@ var decodeTests = []decodeTest{
},
// pointers
{input: "00", ptr: new(*int), value: (*int)(nil)},
{input: "80", ptr: new(*int), value: (*int)(nil)},
{input: "C0", ptr: new(*int), value: (*int)(nil)},
{input: "07", ptr: new(*int), value: intp(7)},
{input: "8108", ptr: new(*int), value: intp(8)},
{input: "C109", ptr: new(*[]int), value: &[]int{9}},
{input: "00", ptr: new(*uint), value: (*uint)(nil)},
{input: "80", ptr: new(*uint), value: (*uint)(nil)},
{input: "C0", ptr: new(*uint), value: (*uint)(nil)},
{input: "07", ptr: new(*uint), value: uintp(7)},
{input: "8108", ptr: new(*uint), value: uintp(8)},
{input: "C109", ptr: new(*[]uint), value: &[]uint{9}},
{input: "C58403030303", ptr: new(*[][]byte), value: &[][]byte{{3, 3, 3, 3}}},
// pointer should be reset to nil
{input: "05", ptr: sharedPtr, value: intp(5)},
{input: "80", ptr: sharedPtr, value: (*int)(nil)},
{input: "05", ptr: sharedPtr, value: uintp(5)},
{input: "80", ptr: sharedPtr, value: (*uint)(nil)},
// interface{}
{input: "00", ptr: new(interface{}), value: []byte{0}},
@ -301,7 +301,7 @@ var decodeTests = []decodeTest{
{input: "C50183040404", ptr: new(interface{}), value: []interface{}{[]byte{1}, []byte{4, 4, 4}}},
}
func intp(i int) *int { return &i }
func uintp(i uint) *uint { return &i }
func runTests(t *testing.T, decode func([]byte, interface{}) error) {
for i, test := range decodeTests {
@ -434,8 +434,8 @@ func ExampleDecode() {
input, _ := hex.DecodeString("C90A1486666F6F626172")
type example struct {
A, B int
private int // private fields are ignored
A, B uint
private uint // private fields are ignored
String string
}
@ -447,7 +447,7 @@ func ExampleDecode() {
fmt.Printf("Decoded value: %#v\n", s)
}
// Output:
// Decoded value: rlp.example{A:10, B:20, private:0, String:"foobar"}
// Decoded value: rlp.example{A:0xa, B:0x14, private:0x0, String:"foobar"}
}
func ExampleStream() {

View File

@ -1,8 +1,6 @@
package rlp
import (
"fmt"
"math/big"
"reflect"
"sync"
)
@ -51,41 +49,14 @@ func cachedTypeInfo1(typ reflect.Type) (*typeinfo, error) {
return typeCache[typ], err
}
var (
decoderInterface = reflect.TypeOf(new(Decoder)).Elem()
bigInt = reflect.TypeOf(big.Int{})
)
func genTypeInfo(typ reflect.Type) (info *typeinfo, err error) {
info = new(typeinfo)
kind := typ.Kind()
switch {
case typ.Implements(decoderInterface):
info.decoder = decodeDecoder
case kind != reflect.Ptr && reflect.PtrTo(typ).Implements(decoderInterface):
info.decoder = decodeDecoderNoPtr
case typ.AssignableTo(reflect.PtrTo(bigInt)):
info.decoder = decodeBigInt
case typ.AssignableTo(bigInt):
info.decoder = decodeBigIntNoPtr
case isInteger(kind):
info.decoder = makeNumDecoder(typ)
case kind == reflect.String:
info.decoder = decodeString
case kind == reflect.Slice || kind == reflect.Array:
info.decoder, err = makeListDecoder(typ)
case kind == reflect.Struct:
info.decoder, err = makeStructDecoder(typ)
case kind == reflect.Ptr:
info.decoder, err = makePtrDecoder(typ)
case kind == reflect.Interface && typ.NumMethod() == 0:
info.decoder = decodeInterface
default:
err = fmt.Errorf("rlp: type %v is not RLP-serializable", typ)
if info.decoder, err = makeDecoder(typ); err != nil {
return nil, err
}
return info, err
return info, nil
}
func isInteger(k reflect.Kind) bool {
return k >= reflect.Int && k <= reflect.Uintptr
func isUint(k reflect.Kind) bool {
return k >= reflect.Uint && k <= reflect.Uintptr
}