From 6788f955c2414b025a4ea44efaf51caf50aa97f0 Mon Sep 17 00:00:00 2001 From: Felix Lange Date: Tue, 14 Apr 2015 12:28:19 +0200 Subject: [PATCH] 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. --- rlp/decode.go | 10 +++++----- rlp/decode_test.go | 2 +- 2 files changed, 6 insertions(+), 6 deletions(-) diff --git a/rlp/decode.go b/rlp/decode.go index 1e39054e64..42be31a2d0 100644 --- a/rlp/decode.go +++ b/rlp/decode.go @@ -37,9 +37,9 @@ type Decoder interface { // DecodeRLP. // // 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. -// If the input has nonzero size, Decode will allocate a new value of -// the type being pointed to. +// input has size zero. If the input has nonzero size, Decode will +// parse the input data into a value of 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 // 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 } dec := func(s *Stream, val reflect.Value) (err error) { - _, size, err := s.Kind() - if err != nil || size == 0 && s.byteval == 0 { + kind, size, err := s.Kind() + if err != nil || size == 0 && kind != Byte { // rearm s.Kind. This is important because the input // position must advance to the next value even though // we don't read anything. diff --git a/rlp/decode_test.go b/rlp/decode_test.go index a64bfe3fdb..e5c7f3761f 100644 --- a/rlp/decode_test.go +++ b/rlp/decode_test.go @@ -378,7 +378,7 @@ var decodeTests = []decodeTest{ }, // 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: "C0", ptr: new(*uint), value: (*uint)(nil)}, {input: "07", ptr: new(*uint), value: uintp(7)},