rlp: fix handling of single byte zero when decoding into a pointer

A single zero byte carries information and should not set the pointer
to nil. This is arguably a corner case. While here, fix the comment
to explain pointer reuse.
This commit is contained in:
Felix Lange 2015-04-14 12:28:19 +02:00
parent 509d0a8d78
commit 6788f955c2
2 changed files with 6 additions and 6 deletions

View File

@ -37,9 +37,9 @@ type Decoder interface {
// DecodeRLP. // DecodeRLP.
// //
// To decode into a pointer, Decode will set the pointer to nil if the // To decode into a pointer, Decode will set the pointer to nil if the
// input has size zero or the input is a single byte with value zero. // input has size zero. If the input has nonzero size, Decode will
// If the input has nonzero size, Decode will allocate a new value of // parse the input data into a value of the type being pointed to.
// the type being pointed to. // If the pointer is non-nil, the existing value will reused.
// //
// To decode into a struct, Decode expects the input to be an RLP // To decode into a struct, Decode expects the input to be an RLP
// list. The decoded elements of the list are assigned to each public // list. The decoded elements of the list are assigned to each public
@ -382,8 +382,8 @@ func makePtrDecoder(typ reflect.Type) (decoder, error) {
return nil, err return nil, err
} }
dec := func(s *Stream, val reflect.Value) (err error) { dec := func(s *Stream, val reflect.Value) (err error) {
_, size, err := s.Kind() kind, size, err := s.Kind()
if err != nil || size == 0 && s.byteval == 0 { if err != nil || size == 0 && kind != Byte {
// rearm s.Kind. This is important because the input // rearm s.Kind. This is important because the input
// position must advance to the next value even though // position must advance to the next value even though
// we don't read anything. // we don't read anything.

View File

@ -378,7 +378,7 @@ var decodeTests = []decodeTest{
}, },
// pointers // pointers
{input: "00", ptr: new(*uint), value: (*uint)(nil)}, {input: "00", ptr: new(*uint), value: uintp(0)},
{input: "80", ptr: new(*uint), value: (*uint)(nil)}, {input: "80", ptr: new(*uint), value: (*uint)(nil)},
{input: "C0", ptr: new(*uint), value: (*uint)(nil)}, {input: "C0", ptr: new(*uint), value: (*uint)(nil)},
{input: "07", ptr: new(*uint), value: uintp(7)}, {input: "07", ptr: new(*uint), value: uintp(7)},