diff --git a/go.mod b/go.mod index f7d0f6bda..9d46bb1d6 100644 --- a/go.mod +++ b/go.mod @@ -67,6 +67,7 @@ require ( golang.org/x/sys v0.0.0-20210816183151-1e6c022a8912 golang.org/x/text v0.3.6 golang.org/x/time v0.0.0-20210220033141-f8bda1e9f3ba + golang.org/x/tools v0.1.0 gopkg.in/natefinch/npipe.v2 v2.0.0-20160621034901-c1b8fa8bdcce gopkg.in/olebedev/go-duktape.v3 v3.0.0-20200619000410-60c24ae608a6 gopkg.in/urfave/cli.v1 v1.20.0 diff --git a/go.sum b/go.sum index 53cee50ab..06a4cabc3 100644 --- a/go.sum +++ b/go.sum @@ -460,6 +460,7 @@ golang.org/x/mod v0.0.0-20190513183733-4bf6d317e70e/go.mod h1:mXi4GBBbnImb6dmsKG golang.org/x/mod v0.1.0/go.mod h1:0QHyrYULN0/3qlju5TqG8bIK38QM8yzMo5ekMj3DlcY= golang.org/x/mod v0.1.1-0.20191105210325-c90efee705ee/go.mod h1:QqPTAvyqsEbceGzBzNggFXnrqF1CaUcvgkdR5Ot7KZg= golang.org/x/mod v0.3.0/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA= +golang.org/x/mod v0.4.2 h1:Gz96sIWK3OalVv/I/qNygP42zyoKp3xptRVCWRFEBvo= golang.org/x/mod v0.4.2/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA= golang.org/x/net v0.0.0-20180724234803-3673e40ba225/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4= golang.org/x/net v0.0.0-20180826012351-8a410e7b638d/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4= @@ -580,6 +581,7 @@ golang.org/x/tools v0.0.0-20191125144606-a911d9008d1f/go.mod h1:b+2E5dAYhXwXZwtn golang.org/x/tools v0.0.0-20191216173652-a0e659d51361/go.mod h1:TB2adYChydJhpapKDTa4BR/hXlZSLoq2Wpct/0txZ28= golang.org/x/tools v0.0.0-20191227053925-7b8e75db28f4/go.mod h1:TB2adYChydJhpapKDTa4BR/hXlZSLoq2Wpct/0txZ28= golang.org/x/tools v0.0.0-20200108203644-89082a384178/go.mod h1:TB2adYChydJhpapKDTa4BR/hXlZSLoq2Wpct/0txZ28= +golang.org/x/tools v0.1.0 h1:po9/4sTYwZU9lPhi1tOrb4hCv3qrhiQ77LZfGa2OjwY= golang.org/x/tools v0.1.0/go.mod h1:xkSsbof2nBLbhDlRMhhhyNLN/zl3eTqcnHD5viDpcZ0= golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0= golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0= diff --git a/rlp/decode.go b/rlp/decode.go index 5f2e5ad5f..9214dbfb3 100644 --- a/rlp/decode.go +++ b/rlp/decode.go @@ -27,6 +27,8 @@ import ( "reflect" "strings" "sync" + + "github.com/ethereum/go-ethereum/rlp/internal/rlpstruct" ) //lint:ignore ST1012 EOL is not an error. @@ -148,7 +150,7 @@ var ( bigInt = reflect.TypeOf(big.Int{}) ) -func makeDecoder(typ reflect.Type, tags tags) (dec decoder, err error) { +func makeDecoder(typ reflect.Type, tags rlpstruct.Tags) (dec decoder, err error) { kind := typ.Kind() switch { case typ == rawValueType: @@ -220,55 +222,20 @@ func decodeBigIntNoPtr(s *Stream, val reflect.Value) error { } func decodeBigInt(s *Stream, val reflect.Value) error { - var buffer []byte - kind, size, err := s.Kind() - switch { - case err != nil: - return wrapStreamError(err, val.Type()) - case kind == List: - return wrapStreamError(ErrExpectedString, val.Type()) - case kind == Byte: - buffer = s.uintbuf[:1] - buffer[0] = s.byteval - s.kind = -1 // re-arm Kind - case size == 0: - // Avoid zero-length read. - s.kind = -1 - case size <= uint64(len(s.uintbuf)): - // For integers smaller than s.uintbuf, allocating a buffer - // can be avoided. - buffer = s.uintbuf[:size] - if err := s.readFull(buffer); err != nil { - return wrapStreamError(err, val.Type()) - } - // Reject inputs where single byte encoding should have been used. - if size == 1 && buffer[0] < 128 { - return wrapStreamError(ErrCanonSize, val.Type()) - } - default: - // For large integers, a temporary buffer is needed. - buffer = make([]byte, size) - if err := s.readFull(buffer); err != nil { - return wrapStreamError(err, val.Type()) - } - } - - // Reject leading zero bytes. - if len(buffer) > 0 && buffer[0] == 0 { - return wrapStreamError(ErrCanonInt, val.Type()) - } - - // Set the integer bytes. i := val.Interface().(*big.Int) if i == nil { i = new(big.Int) val.Set(reflect.ValueOf(i)) } - i.SetBytes(buffer) + + err := s.decodeBigInt(i) + if err != nil { + return wrapStreamError(err, val.Type()) + } return nil } -func makeListDecoder(typ reflect.Type, tag tags) (decoder, error) { +func makeListDecoder(typ reflect.Type, tag rlpstruct.Tags) (decoder, error) { etype := typ.Elem() if etype.Kind() == reflect.Uint8 && !reflect.PtrTo(etype).Implements(decoderInterface) { if typ.Kind() == reflect.Array { @@ -276,7 +243,7 @@ func makeListDecoder(typ reflect.Type, tag tags) (decoder, error) { } return decodeByteSlice, nil } - etypeinfo := theTC.infoWhileGenerating(etype, tags{}) + etypeinfo := theTC.infoWhileGenerating(etype, rlpstruct.Tags{}) if etypeinfo.decoderErr != nil { return nil, etypeinfo.decoderErr } @@ -286,7 +253,7 @@ func makeListDecoder(typ reflect.Type, tag tags) (decoder, error) { dec = func(s *Stream, val reflect.Value) error { return decodeListArray(s, val, etypeinfo.decoder) } - case tag.tail: + case tag.Tail: // A slice with "tail" tag can occur as the last field // of a struct and is supposed to swallow all remaining // list elements. The struct decoder already called s.List, @@ -451,16 +418,16 @@ func zeroFields(structval reflect.Value, fields []field) { } // makePtrDecoder creates a decoder that decodes into the pointer's element type. -func makePtrDecoder(typ reflect.Type, tag tags) (decoder, error) { +func makePtrDecoder(typ reflect.Type, tag rlpstruct.Tags) (decoder, error) { etype := typ.Elem() - etypeinfo := theTC.infoWhileGenerating(etype, tags{}) + etypeinfo := theTC.infoWhileGenerating(etype, rlpstruct.Tags{}) switch { case etypeinfo.decoderErr != nil: return nil, etypeinfo.decoderErr - case !tag.nilOK: + case !tag.NilOK: return makeSimplePtrDecoder(etype, etypeinfo), nil default: - return makeNilPtrDecoder(etype, etypeinfo, tag.nilKind), nil + return makeNilPtrDecoder(etype, etypeinfo, tag), nil } } @@ -481,9 +448,13 @@ func makeSimplePtrDecoder(etype reflect.Type, etypeinfo *typeinfo) decoder { // values are decoded into a value of the element type, just like makePtrDecoder does. // // This decoder is used for pointer-typed struct fields with struct tag "nil". -func makeNilPtrDecoder(etype reflect.Type, etypeinfo *typeinfo, nilKind Kind) decoder { +func makeNilPtrDecoder(etype reflect.Type, etypeinfo *typeinfo, ts rlpstruct.Tags) decoder { typ := reflect.PtrTo(etype) nilPtr := reflect.Zero(typ) + + // Determine the value kind that results in nil pointer. + nilKind := typeNilKind(etype, ts) + return func(s *Stream, val reflect.Value) (err error) { kind, size, err := s.Kind() if err != nil { @@ -659,6 +630,37 @@ func (s *Stream) Bytes() ([]byte, error) { } } +// ReadBytes decodes the next RLP value and stores the result in b. +// The value size must match len(b) exactly. +func (s *Stream) ReadBytes(b []byte) error { + kind, size, err := s.Kind() + if err != nil { + return err + } + switch kind { + case Byte: + if len(b) != 1 { + return fmt.Errorf("input value has wrong size 1, want %d", len(b)) + } + b[0] = s.byteval + s.kind = -1 // rearm Kind + return nil + case String: + if uint64(len(b)) != size { + return fmt.Errorf("input value has wrong size %d, want %d", size, len(b)) + } + if err = s.readFull(b); err != nil { + return err + } + if size == 1 && b[0] < 128 { + return ErrCanonSize + } + return nil + default: + return ErrExpectedString + } +} + // Raw reads a raw encoded value including RLP type information. func (s *Stream) Raw() ([]byte, error) { kind, size, err := s.Kind() @@ -687,10 +689,31 @@ func (s *Stream) Raw() ([]byte, error) { // Uint reads an RLP string of up to 8 bytes and returns its contents // as an unsigned integer. If the input does not contain an RLP string, the // returned error will be ErrExpectedString. +// +// Deprecated: use s.Uint64 instead. func (s *Stream) Uint() (uint64, error) { return s.uint(64) } +func (s *Stream) Uint64() (uint64, error) { + return s.uint(64) +} + +func (s *Stream) Uint32() (uint32, error) { + i, err := s.uint(32) + return uint32(i), err +} + +func (s *Stream) Uint16() (uint16, error) { + i, err := s.uint(16) + return uint16(i), err +} + +func (s *Stream) Uint8() (uint8, error) { + i, err := s.uint(8) + return uint8(i), err +} + func (s *Stream) uint(maxbits int) (uint64, error) { kind, size, err := s.Kind() if err != nil { @@ -781,6 +804,65 @@ func (s *Stream) ListEnd() error { return nil } +// MoreDataInList reports whether the current list context contains +// more data to be read. +func (s *Stream) MoreDataInList() bool { + _, listLimit := s.listLimit() + return listLimit > 0 +} + +// BigInt decodes an arbitrary-size integer value. +func (s *Stream) BigInt() (*big.Int, error) { + i := new(big.Int) + if err := s.decodeBigInt(i); err != nil { + return nil, err + } + return i, nil +} + +func (s *Stream) decodeBigInt(dst *big.Int) error { + var buffer []byte + kind, size, err := s.Kind() + switch { + case err != nil: + return err + case kind == List: + return ErrExpectedString + case kind == Byte: + buffer = s.uintbuf[:1] + buffer[0] = s.byteval + s.kind = -1 // re-arm Kind + case size == 0: + // Avoid zero-length read. + s.kind = -1 + case size <= uint64(len(s.uintbuf)): + // For integers smaller than s.uintbuf, allocating a buffer + // can be avoided. + buffer = s.uintbuf[:size] + if err := s.readFull(buffer); err != nil { + return err + } + // Reject inputs where single byte encoding should have been used. + if size == 1 && buffer[0] < 128 { + return ErrCanonSize + } + default: + // For large integers, a temporary buffer is needed. + buffer = make([]byte, size) + if err := s.readFull(buffer); err != nil { + return err + } + } + + // Reject leading zero bytes. + if len(buffer) > 0 && buffer[0] == 0 { + return ErrCanonInt + } + // Set the integer bytes. + dst.SetBytes(buffer) + return nil +} + // Decode decodes a value and stores the result in the value pointed // to by val. Please see the documentation for the Decode function // to learn about the decoding rules. diff --git a/rlp/decode_test.go b/rlp/decode_test.go index 7c3dafeac..babdf3891 100644 --- a/rlp/decode_test.go +++ b/rlp/decode_test.go @@ -286,6 +286,47 @@ func TestStreamRaw(t *testing.T) { } } +func TestStreamReadBytes(t *testing.T) { + tests := []struct { + input string + size int + err string + }{ + // kind List + {input: "C0", size: 1, err: "rlp: expected String or Byte"}, + // kind Byte + {input: "04", size: 0, err: "input value has wrong size 1, want 0"}, + {input: "04", size: 1}, + {input: "04", size: 2, err: "input value has wrong size 1, want 2"}, + // kind String + {input: "820102", size: 0, err: "input value has wrong size 2, want 0"}, + {input: "820102", size: 1, err: "input value has wrong size 2, want 1"}, + {input: "820102", size: 2}, + {input: "820102", size: 3, err: "input value has wrong size 2, want 3"}, + } + + for _, test := range tests { + test := test + name := fmt.Sprintf("input_%s/size_%d", test.input, test.size) + t.Run(name, func(t *testing.T) { + s := NewStream(bytes.NewReader(unhex(test.input)), 0) + b := make([]byte, test.size) + err := s.ReadBytes(b) + if test.err == "" { + if err != nil { + t.Errorf("unexpected error %q", err) + } + } else { + if err == nil { + t.Errorf("expected error, got nil") + } else if err.Error() != test.err { + t.Errorf("wrong error %q", err) + } + } + }) + } +} + func TestDecodeErrors(t *testing.T) { r := bytes.NewReader(nil) @@ -990,7 +1031,7 @@ func TestInvalidOptionalField(t *testing.T) { v interface{} err string }{ - {v: new(invalid1), err: `rlp: struct field rlp.invalid1.B needs "optional" tag`}, + {v: new(invalid1), err: `rlp: invalid struct tag "" for rlp.invalid1.B (must be optional because preceding field "A" is optional)`}, {v: new(invalid2), err: `rlp: invalid struct tag "optional" for rlp.invalid2.T (also has "tail" tag)`}, {v: new(invalid3), err: `rlp: invalid struct tag "tail" for rlp.invalid3.T (also has "optional" tag)`}, } diff --git a/rlp/encbuffer.go b/rlp/encbuffer.go new file mode 100644 index 000000000..0e200a9a3 --- /dev/null +++ b/rlp/encbuffer.go @@ -0,0 +1,352 @@ +package rlp + +import ( + "io" + "math/big" + "reflect" + "sync" +) + +type encBuffer struct { + str []byte // string data, contains everything except list headers + lheads []listhead // all list headers + lhsize int // sum of sizes of all encoded list headers + sizebuf [9]byte // auxiliary buffer for uint encoding +} + +// The global encBuffer pool. +var encBufferPool = sync.Pool{ + New: func() interface{} { return new(encBuffer) }, +} + +func getEncBuffer() *encBuffer { + buf := encBufferPool.Get().(*encBuffer) + buf.reset() + return buf +} + +func (buf *encBuffer) reset() { + buf.lhsize = 0 + buf.str = buf.str[:0] + buf.lheads = buf.lheads[:0] +} + +// size returns the length of the encoded data. +func (buf *encBuffer) size() int { + return len(buf.str) + buf.lhsize +} + +// toBytes creates the encoder output. +func (w *encBuffer) toBytes() []byte { + out := make([]byte, w.size()) + strpos := 0 + pos := 0 + for _, head := range w.lheads { + // write string data before header + n := copy(out[pos:], w.str[strpos:head.offset]) + pos += n + strpos += n + // write the header + enc := head.encode(out[pos:]) + pos += len(enc) + } + // copy string data after the last list header + copy(out[pos:], w.str[strpos:]) + return out +} + +// toWriter writes the encoder output to w. +func (buf *encBuffer) toWriter(w io.Writer) (err error) { + strpos := 0 + for _, head := range buf.lheads { + // write string data before header + if head.offset-strpos > 0 { + n, err := w.Write(buf.str[strpos:head.offset]) + strpos += n + if err != nil { + return err + } + } + // write the header + enc := head.encode(buf.sizebuf[:]) + if _, err = w.Write(enc); err != nil { + return err + } + } + if strpos < len(buf.str) { + // write string data after the last list header + _, err = w.Write(buf.str[strpos:]) + } + return err +} + +// Write implements io.Writer and appends b directly to the output. +func (buf *encBuffer) Write(b []byte) (int, error) { + buf.str = append(buf.str, b...) + return len(b), nil +} + +// writeBool writes b as the integer 0 (false) or 1 (true). +func (buf *encBuffer) writeBool(b bool) { + if b { + buf.str = append(buf.str, 0x01) + } else { + buf.str = append(buf.str, 0x80) + } +} + +func (buf *encBuffer) writeUint64(i uint64) { + if i == 0 { + buf.str = append(buf.str, 0x80) + } else if i < 128 { + // fits single byte + buf.str = append(buf.str, byte(i)) + } else { + s := putint(buf.sizebuf[1:], i) + buf.sizebuf[0] = 0x80 + byte(s) + buf.str = append(buf.str, buf.sizebuf[:s+1]...) + } +} + +func (buf *encBuffer) writeBytes(b []byte) { + if len(b) == 1 && b[0] <= 0x7F { + // fits single byte, no string header + buf.str = append(buf.str, b[0]) + } else { + buf.encodeStringHeader(len(b)) + buf.str = append(buf.str, b...) + } +} + +// wordBytes is the number of bytes in a big.Word +const wordBytes = (32 << (uint64(^big.Word(0)) >> 63)) / 8 + +// writeBigInt writes i as an integer. +func (w *encBuffer) writeBigInt(i *big.Int) { + bitlen := i.BitLen() + if bitlen <= 64 { + w.writeUint64(i.Uint64()) + return + } + // Integer is larger than 64 bits, encode from i.Bits(). + // The minimal byte length is bitlen rounded up to the next + // multiple of 8, divided by 8. + length := ((bitlen + 7) & -8) >> 3 + w.encodeStringHeader(length) + w.str = append(w.str, make([]byte, length)...) + index := length + buf := w.str[len(w.str)-length:] + for _, d := range i.Bits() { + for j := 0; j < wordBytes && index > 0; j++ { + index-- + buf[index] = byte(d) + d >>= 8 + } + } +} + +// list adds a new list header to the header stack. It returns the index of the header. +// Call listEnd with this index after encoding the content of the list. +func (buf *encBuffer) list() int { + buf.lheads = append(buf.lheads, listhead{offset: len(buf.str), size: buf.lhsize}) + return len(buf.lheads) - 1 +} + +func (buf *encBuffer) listEnd(index int) { + lh := &buf.lheads[index] + lh.size = buf.size() - lh.offset - lh.size + if lh.size < 56 { + buf.lhsize++ // length encoded into kind tag + } else { + buf.lhsize += 1 + intsize(uint64(lh.size)) + } +} + +func (buf *encBuffer) encode(val interface{}) error { + rval := reflect.ValueOf(val) + writer, err := cachedWriter(rval.Type()) + if err != nil { + return err + } + return writer(rval, buf) +} + +func (buf *encBuffer) encodeStringHeader(size int) { + if size < 56 { + buf.str = append(buf.str, 0x80+byte(size)) + } else { + sizesize := putint(buf.sizebuf[1:], uint64(size)) + buf.sizebuf[0] = 0xB7 + byte(sizesize) + buf.str = append(buf.str, buf.sizebuf[:sizesize+1]...) + } +} + +// encReader is the io.Reader returned by EncodeToReader. +// It releases its encbuf at EOF. +type encReader struct { + buf *encBuffer // the buffer we're reading from. this is nil when we're at EOF. + lhpos int // index of list header that we're reading + strpos int // current position in string buffer + piece []byte // next piece to be read +} + +func (r *encReader) Read(b []byte) (n int, err error) { + for { + if r.piece = r.next(); r.piece == nil { + // Put the encode buffer back into the pool at EOF when it + // is first encountered. Subsequent calls still return EOF + // as the error but the buffer is no longer valid. + if r.buf != nil { + encBufferPool.Put(r.buf) + r.buf = nil + } + return n, io.EOF + } + nn := copy(b[n:], r.piece) + n += nn + if nn < len(r.piece) { + // piece didn't fit, see you next time. + r.piece = r.piece[nn:] + return n, nil + } + r.piece = nil + } +} + +// next returns the next piece of data to be read. +// it returns nil at EOF. +func (r *encReader) next() []byte { + switch { + case r.buf == nil: + return nil + + case r.piece != nil: + // There is still data available for reading. + return r.piece + + case r.lhpos < len(r.buf.lheads): + // We're before the last list header. + head := r.buf.lheads[r.lhpos] + sizebefore := head.offset - r.strpos + if sizebefore > 0 { + // String data before header. + p := r.buf.str[r.strpos:head.offset] + r.strpos += sizebefore + return p + } + r.lhpos++ + return head.encode(r.buf.sizebuf[:]) + + case r.strpos < len(r.buf.str): + // String data at the end, after all list headers. + p := r.buf.str[r.strpos:] + r.strpos = len(r.buf.str) + return p + + default: + return nil + } +} + +// EncoderBuffer is a buffer for incremental encoding. +// +// The zero value is NOT ready for use. To get a usable buffer, +// create it using NewEncoderBuffer or call Reset. +type EncoderBuffer struct { + buf *encBuffer + dst io.Writer + + ownBuffer bool +} + +// NewEncoderBuffer creates an encoder buffer. +func NewEncoderBuffer(dst io.Writer) EncoderBuffer { + var w EncoderBuffer + w.Reset(dst) + return w +} + +// Reset truncates the buffer and sets the output destination. +func (w *EncoderBuffer) Reset(dst io.Writer) { + if w.buf != nil && !w.ownBuffer { + panic("can't Reset derived EncoderBuffer") + } + + // If the destination writer has an *encBuffer, use it. + // Note that w.ownBuffer is left false here. + if dst != nil { + if outer, ok := dst.(*encBuffer); ok { + *w = EncoderBuffer{outer, nil, false} + return + } + if outer, ok := dst.(EncoderBuffer); ok { + *w = EncoderBuffer{outer.buf, nil, false} + return + } + } + + // Get a fresh buffer. + if w.buf == nil { + w.buf = encBufferPool.Get().(*encBuffer) + w.ownBuffer = true + } + w.buf.reset() + w.dst = dst +} + +// Flush writes encoded RLP data to the output writer. This can only be called once. +// If you want to re-use the buffer after Flush, you must call Reset. +func (w *EncoderBuffer) Flush() error { + var err error + if w.dst != nil { + err = w.buf.toWriter(w.dst) + } + // Release the internal buffer. + if w.ownBuffer { + encBufferPool.Put(w.buf) + } + *w = EncoderBuffer{} + return err +} + +// ToBytes returns the encoded bytes. +func (w *EncoderBuffer) ToBytes() []byte { + return w.buf.toBytes() +} + +// Write appends b directly to the encoder output. +func (w EncoderBuffer) Write(b []byte) (int, error) { + return w.buf.Write(b) +} + +// WriteBool writes b as the integer 0 (false) or 1 (true). +func (w EncoderBuffer) WriteBool(b bool) { + w.buf.writeBool(b) +} + +// WriteUint64 encodes an unsigned integer. +func (w EncoderBuffer) WriteUint64(i uint64) { + w.buf.writeUint64(i) +} + +// WriteBigInt encodes a big.Int as an RLP string. +// Note: Unlike with Encode, the sign of i is ignored. +func (w EncoderBuffer) WriteBigInt(i *big.Int) { + w.buf.writeBigInt(i) +} + +// WriteBytes encodes b as an RLP string. +func (w EncoderBuffer) WriteBytes(b []byte) { + w.buf.writeBytes(b) +} + +// List starts a list. It returns an internal index. Call EndList with +// this index after encoding the content to finish the list. +func (w EncoderBuffer) List() int { + return w.buf.list() +} + +// ListEnd finishes the given list. +func (w EncoderBuffer) ListEnd(index int) { + w.buf.listEnd(index) +} diff --git a/rlp/encbuffer_example_test.go b/rlp/encbuffer_example_test.go new file mode 100644 index 000000000..ee15d82a7 --- /dev/null +++ b/rlp/encbuffer_example_test.go @@ -0,0 +1,45 @@ +// Copyright 2022 The go-ethereum Authors +// This file is part of the go-ethereum library. +// +// The go-ethereum library is free software: you can redistribute it and/or modify +// it under the terms of the GNU Lesser General Public License as published by +// the Free Software Foundation, either version 3 of the License, or +// (at your option) any later version. +// +// The go-ethereum library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public License +// along with the go-ethereum library. If not, see . + +package rlp_test + +import ( + "bytes" + "fmt" + + "github.com/ethereum/go-ethereum/rlp" +) + +func ExampleEncoderBuffer() { + var w bytes.Buffer + + // Encode [4, [5, 6]] to w. + buf := rlp.NewEncoderBuffer(&w) + l1 := buf.List() + buf.WriteUint64(4) + l2 := buf.List() + buf.WriteUint64(5) + buf.WriteUint64(6) + buf.ListEnd(l2) + buf.ListEnd(l1) + + if err := buf.Flush(); err != nil { + panic(err) + } + fmt.Printf("%X\n", w.Bytes()) + // Output: + // C404C20506 +} diff --git a/rlp/encode.go b/rlp/encode.go index 1623e97a3..c3523369f 100644 --- a/rlp/encode.go +++ b/rlp/encode.go @@ -17,11 +17,13 @@ package rlp import ( + "errors" "fmt" "io" "math/big" "reflect" - "sync" + + "github.com/ethereum/go-ethereum/rlp/internal/rlpstruct" ) var ( @@ -31,6 +33,8 @@ var ( EmptyList = []byte{0xC0} ) +var ErrNegativeBigInt = errors.New("rlp: cannot encode negative big.Int") + // Encoder is implemented by types that require custom // encoding rules or want to encode private fields. type Encoder interface { @@ -51,30 +55,33 @@ type Encoder interface { // // Please see package-level documentation of encoding rules. func Encode(w io.Writer, val interface{}) error { - if outer, ok := w.(*encbuf); ok { - // Encode was called by some type's EncodeRLP. - // Avoid copying by writing to the outer encbuf directly. - return outer.encode(val) + // Optimization: reuse *encBuffer when called by EncodeRLP. + if buf, ok := w.(*encBuffer); ok { + return buf.encode(val) } - eb := encbufPool.Get().(*encbuf) - defer encbufPool.Put(eb) - eb.reset() - if err := eb.encode(val); err != nil { + if ebuf, ok := w.(EncoderBuffer); ok { + return ebuf.buf.encode(val) + } + + buf := getEncBuffer() + defer encBufferPool.Put(buf) + + if err := buf.encode(val); err != nil { return err } - return eb.toWriter(w) + return buf.toWriter(w) } // EncodeToBytes returns the RLP encoding of val. // Please see package-level documentation for the encoding rules. func EncodeToBytes(val interface{}) ([]byte, error) { - eb := encbufPool.Get().(*encbuf) - defer encbufPool.Put(eb) - eb.reset() - if err := eb.encode(val); err != nil { + buf := getEncBuffer() + defer encBufferPool.Put(buf) + + if err := buf.encode(val); err != nil { return nil, err } - return eb.toBytes(), nil + return buf.toBytes(), nil } // EncodeToReader returns a reader from which the RLP encoding of val @@ -83,12 +90,15 @@ func EncodeToBytes(val interface{}) ([]byte, error) { // // Please see the documentation of Encode for the encoding rules. func EncodeToReader(val interface{}) (size int, r io.Reader, err error) { - eb := encbufPool.Get().(*encbuf) - eb.reset() - if err := eb.encode(val); err != nil { + buf := getEncBuffer() + if err := buf.encode(val); err != nil { + encBufferPool.Put(buf) return 0, nil, err } - return eb.size(), &encReader{buf: eb}, nil + // Note: can't put the reader back into the pool here + // because it is held by encReader. The reader puts it + // back when it has been fully consumed. + return buf.size(), &encReader{buf: buf}, nil } type listhead struct { @@ -123,207 +133,10 @@ func puthead(buf []byte, smalltag, largetag byte, size uint64) int { return sizesize + 1 } -type encbuf struct { - str []byte // string data, contains everything except list headers - lheads []listhead // all list headers - lhsize int // sum of sizes of all encoded list headers - sizebuf [9]byte // auxiliary buffer for uint encoding -} - -// encbufs are pooled. -var encbufPool = sync.Pool{ - New: func() interface{} { return new(encbuf) }, -} - -func (w *encbuf) reset() { - w.lhsize = 0 - w.str = w.str[:0] - w.lheads = w.lheads[:0] -} - -// encbuf implements io.Writer so it can be passed it into EncodeRLP. -func (w *encbuf) Write(b []byte) (int, error) { - w.str = append(w.str, b...) - return len(b), nil -} - -func (w *encbuf) encode(val interface{}) error { - rval := reflect.ValueOf(val) - writer, err := cachedWriter(rval.Type()) - if err != nil { - return err - } - return writer(rval, w) -} - -func (w *encbuf) encodeStringHeader(size int) { - if size < 56 { - w.str = append(w.str, 0x80+byte(size)) - } else { - sizesize := putint(w.sizebuf[1:], uint64(size)) - w.sizebuf[0] = 0xB7 + byte(sizesize) - w.str = append(w.str, w.sizebuf[:sizesize+1]...) - } -} - -func (w *encbuf) encodeString(b []byte) { - if len(b) == 1 && b[0] <= 0x7F { - // fits single byte, no string header - w.str = append(w.str, b[0]) - } else { - w.encodeStringHeader(len(b)) - w.str = append(w.str, b...) - } -} - -func (w *encbuf) encodeUint(i uint64) { - if i == 0 { - w.str = append(w.str, 0x80) - } else if i < 128 { - // fits single byte - w.str = append(w.str, byte(i)) - } else { - s := putint(w.sizebuf[1:], i) - w.sizebuf[0] = 0x80 + byte(s) - w.str = append(w.str, w.sizebuf[:s+1]...) - } -} - -// list adds a new list header to the header stack. It returns the index -// of the header. The caller must call listEnd with this index after encoding -// the content of the list. -func (w *encbuf) list() int { - w.lheads = append(w.lheads, listhead{offset: len(w.str), size: w.lhsize}) - return len(w.lheads) - 1 -} - -func (w *encbuf) listEnd(index int) { - lh := &w.lheads[index] - lh.size = w.size() - lh.offset - lh.size - if lh.size < 56 { - w.lhsize++ // length encoded into kind tag - } else { - w.lhsize += 1 + intsize(uint64(lh.size)) - } -} - -func (w *encbuf) size() int { - return len(w.str) + w.lhsize -} - -func (w *encbuf) toBytes() []byte { - out := make([]byte, w.size()) - strpos := 0 - pos := 0 - for _, head := range w.lheads { - // write string data before header - n := copy(out[pos:], w.str[strpos:head.offset]) - pos += n - strpos += n - // write the header - enc := head.encode(out[pos:]) - pos += len(enc) - } - // copy string data after the last list header - copy(out[pos:], w.str[strpos:]) - return out -} - -func (w *encbuf) toWriter(out io.Writer) (err error) { - strpos := 0 - for _, head := range w.lheads { - // write string data before header - if head.offset-strpos > 0 { - n, err := out.Write(w.str[strpos:head.offset]) - strpos += n - if err != nil { - return err - } - } - // write the header - enc := head.encode(w.sizebuf[:]) - if _, err = out.Write(enc); err != nil { - return err - } - } - if strpos < len(w.str) { - // write string data after the last list header - _, err = out.Write(w.str[strpos:]) - } - return err -} - -// encReader is the io.Reader returned by EncodeToReader. -// It releases its encbuf at EOF. -type encReader struct { - buf *encbuf // the buffer we're reading from. this is nil when we're at EOF. - lhpos int // index of list header that we're reading - strpos int // current position in string buffer - piece []byte // next piece to be read -} - -func (r *encReader) Read(b []byte) (n int, err error) { - for { - if r.piece = r.next(); r.piece == nil { - // Put the encode buffer back into the pool at EOF when it - // is first encountered. Subsequent calls still return EOF - // as the error but the buffer is no longer valid. - if r.buf != nil { - encbufPool.Put(r.buf) - r.buf = nil - } - return n, io.EOF - } - nn := copy(b[n:], r.piece) - n += nn - if nn < len(r.piece) { - // piece didn't fit, see you next time. - r.piece = r.piece[nn:] - return n, nil - } - r.piece = nil - } -} - -// next returns the next piece of data to be read. -// it returns nil at EOF. -func (r *encReader) next() []byte { - switch { - case r.buf == nil: - return nil - - case r.piece != nil: - // There is still data available for reading. - return r.piece - - case r.lhpos < len(r.buf.lheads): - // We're before the last list header. - head := r.buf.lheads[r.lhpos] - sizebefore := head.offset - r.strpos - if sizebefore > 0 { - // String data before header. - p := r.buf.str[r.strpos:head.offset] - r.strpos += sizebefore - return p - } - r.lhpos++ - return head.encode(r.buf.sizebuf[:]) - - case r.strpos < len(r.buf.str): - // String data at the end, after all list headers. - p := r.buf.str[r.strpos:] - r.strpos = len(r.buf.str) - return p - - default: - return nil - } -} - var encoderInterface = reflect.TypeOf(new(Encoder)).Elem() // makeWriter creates a writer function for the given type. -func makeWriter(typ reflect.Type, ts tags) (writer, error) { +func makeWriter(typ reflect.Type, ts rlpstruct.Tags) (writer, error) { kind := typ.Kind() switch { case typ == rawValueType: @@ -357,71 +170,45 @@ func makeWriter(typ reflect.Type, ts tags) (writer, error) { } } -func writeRawValue(val reflect.Value, w *encbuf) error { +func writeRawValue(val reflect.Value, w *encBuffer) error { w.str = append(w.str, val.Bytes()...) return nil } -func writeUint(val reflect.Value, w *encbuf) error { - w.encodeUint(val.Uint()) +func writeUint(val reflect.Value, w *encBuffer) error { + w.writeUint64(val.Uint()) return nil } -func writeBool(val reflect.Value, w *encbuf) error { - if val.Bool() { - w.str = append(w.str, 0x01) - } else { - w.str = append(w.str, 0x80) - } +func writeBool(val reflect.Value, w *encBuffer) error { + w.writeBool(val.Bool()) return nil } -func writeBigIntPtr(val reflect.Value, w *encbuf) error { +func writeBigIntPtr(val reflect.Value, w *encBuffer) error { ptr := val.Interface().(*big.Int) if ptr == nil { w.str = append(w.str, 0x80) return nil } - return writeBigInt(ptr, w) -} - -func writeBigIntNoPtr(val reflect.Value, w *encbuf) error { - i := val.Interface().(big.Int) - return writeBigInt(&i, w) -} - -// wordBytes is the number of bytes in a big.Word -const wordBytes = (32 << (uint64(^big.Word(0)) >> 63)) / 8 - -func writeBigInt(i *big.Int, w *encbuf) error { - if i.Sign() == -1 { - return fmt.Errorf("rlp: cannot encode negative *big.Int") - } - bitlen := i.BitLen() - if bitlen <= 64 { - w.encodeUint(i.Uint64()) - return nil - } - // Integer is larger than 64 bits, encode from i.Bits(). - // The minimal byte length is bitlen rounded up to the next - // multiple of 8, divided by 8. - length := ((bitlen + 7) & -8) >> 3 - w.encodeStringHeader(length) - w.str = append(w.str, make([]byte, length)...) - index := length - buf := w.str[len(w.str)-length:] - for _, d := range i.Bits() { - for j := 0; j < wordBytes && index > 0; j++ { - index-- - buf[index] = byte(d) - d >>= 8 - } + if ptr.Sign() == -1 { + return ErrNegativeBigInt } + w.writeBigInt(ptr) return nil } -func writeBytes(val reflect.Value, w *encbuf) error { - w.encodeString(val.Bytes()) +func writeBigIntNoPtr(val reflect.Value, w *encBuffer) error { + i := val.Interface().(big.Int) + if i.Sign() == -1 { + return ErrNegativeBigInt + } + w.writeBigInt(&i) + return nil +} + +func writeBytes(val reflect.Value, w *encBuffer) error { + w.writeBytes(val.Bytes()) return nil } @@ -433,7 +220,7 @@ func makeByteArrayWriter(typ reflect.Type) writer { return writeLengthOneByteArray default: length := typ.Len() - return func(val reflect.Value, w *encbuf) error { + return func(val reflect.Value, w *encBuffer) error { if !val.CanAddr() { // Getting the byte slice of val requires it to be addressable. Make it // addressable by copying. @@ -449,12 +236,12 @@ func makeByteArrayWriter(typ reflect.Type) writer { } } -func writeLengthZeroByteArray(val reflect.Value, w *encbuf) error { +func writeLengthZeroByteArray(val reflect.Value, w *encBuffer) error { w.str = append(w.str, 0x80) return nil } -func writeLengthOneByteArray(val reflect.Value, w *encbuf) error { +func writeLengthOneByteArray(val reflect.Value, w *encBuffer) error { b := byte(val.Index(0).Uint()) if b <= 0x7f { w.str = append(w.str, b) @@ -464,7 +251,7 @@ func writeLengthOneByteArray(val reflect.Value, w *encbuf) error { return nil } -func writeString(val reflect.Value, w *encbuf) error { +func writeString(val reflect.Value, w *encBuffer) error { s := val.String() if len(s) == 1 && s[0] <= 0x7f { // fits single byte, no string header @@ -476,7 +263,7 @@ func writeString(val reflect.Value, w *encbuf) error { return nil } -func writeInterface(val reflect.Value, w *encbuf) error { +func writeInterface(val reflect.Value, w *encBuffer) error { if val.IsNil() { // Write empty list. This is consistent with the previous RLP // encoder that we had and should therefore avoid any @@ -492,17 +279,17 @@ func writeInterface(val reflect.Value, w *encbuf) error { return writer(eval, w) } -func makeSliceWriter(typ reflect.Type, ts tags) (writer, error) { - etypeinfo := theTC.infoWhileGenerating(typ.Elem(), tags{}) +func makeSliceWriter(typ reflect.Type, ts rlpstruct.Tags) (writer, error) { + etypeinfo := theTC.infoWhileGenerating(typ.Elem(), rlpstruct.Tags{}) if etypeinfo.writerErr != nil { return nil, etypeinfo.writerErr } var wfn writer - if ts.tail { + if ts.Tail { // This is for struct tail slices. // w.list is not called for them. - wfn = func(val reflect.Value, w *encbuf) error { + wfn = func(val reflect.Value, w *encBuffer) error { vlen := val.Len() for i := 0; i < vlen; i++ { if err := etypeinfo.writer(val.Index(i), w); err != nil { @@ -513,7 +300,7 @@ func makeSliceWriter(typ reflect.Type, ts tags) (writer, error) { } } else { // This is for regular slices and arrays. - wfn = func(val reflect.Value, w *encbuf) error { + wfn = func(val reflect.Value, w *encBuffer) error { vlen := val.Len() if vlen == 0 { w.str = append(w.str, 0xC0) @@ -547,7 +334,7 @@ func makeStructWriter(typ reflect.Type) (writer, error) { firstOptionalField := firstOptionalField(fields) if firstOptionalField == len(fields) { // This is the writer function for structs without any optional fields. - writer = func(val reflect.Value, w *encbuf) error { + writer = func(val reflect.Value, w *encBuffer) error { lh := w.list() for _, f := range fields { if err := f.info.writer(val.Field(f.index), w); err != nil { @@ -560,7 +347,7 @@ func makeStructWriter(typ reflect.Type) (writer, error) { } else { // If there are any "optional" fields, the writer needs to perform additional // checks to determine the output list length. - writer = func(val reflect.Value, w *encbuf) error { + writer = func(val reflect.Value, w *encBuffer) error { lastField := len(fields) - 1 for ; lastField >= firstOptionalField; lastField-- { if !val.Field(fields[lastField].index).IsZero() { @@ -580,33 +367,18 @@ func makeStructWriter(typ reflect.Type) (writer, error) { return writer, nil } -// nilEncoding returns the encoded value of a nil pointer. -func nilEncoding(typ reflect.Type, ts tags) uint8 { - var nilKind Kind - if ts.nilOK { - nilKind = ts.nilKind // use struct tag if provided - } else { - nilKind = defaultNilKind(typ.Elem()) +func makePtrWriter(typ reflect.Type, ts rlpstruct.Tags) (writer, error) { + nilEncoding := byte(0xC0) + if typeNilKind(typ.Elem(), ts) == String { + nilEncoding = 0x80 } - switch nilKind { - case String: - return 0x80 - case List: - return 0xC0 - default: - panic(fmt.Errorf("rlp: invalid nil kind %d", nilKind)) - } -} - -func makePtrWriter(typ reflect.Type, ts tags) (writer, error) { - etypeinfo := theTC.infoWhileGenerating(typ.Elem(), tags{}) + etypeinfo := theTC.infoWhileGenerating(typ.Elem(), rlpstruct.Tags{}) if etypeinfo.writerErr != nil { return nil, etypeinfo.writerErr } - nilEncoding := nilEncoding(typ, ts) - writer := func(val reflect.Value, w *encbuf) error { + writer := func(val reflect.Value, w *encBuffer) error { if ev := val.Elem(); ev.IsValid() { return etypeinfo.writer(ev, w) } @@ -618,11 +390,11 @@ func makePtrWriter(typ reflect.Type, ts tags) (writer, error) { func makeEncoderWriter(typ reflect.Type) writer { if typ.Implements(encoderInterface) { - return func(val reflect.Value, w *encbuf) error { + return func(val reflect.Value, w *encBuffer) error { return val.Interface().(Encoder).EncodeRLP(w) } } - w := func(val reflect.Value, w *encbuf) error { + w := func(val reflect.Value, w *encBuffer) error { if !val.CanAddr() { // package json simply doesn't call MarshalJSON for this case, but encodes the // value as if it didn't implement the interface. We don't want to handle it that diff --git a/rlp/encode_test.go b/rlp/encode_test.go index a63743440..5dcfd78fd 100644 --- a/rlp/encode_test.go +++ b/rlp/encode_test.go @@ -145,7 +145,8 @@ var encTests = []encTest{ {val: *big.NewInt(0xFFFFFF), output: "83FFFFFF"}, // negative ints are not supported - {val: big.NewInt(-1), error: "rlp: cannot encode negative *big.Int"}, + {val: big.NewInt(-1), error: "rlp: cannot encode negative big.Int"}, + {val: *big.NewInt(-1), error: "rlp: cannot encode negative big.Int"}, // byte arrays {val: [0]byte{}, output: "80"}, diff --git a/rlp/encoder_example_test.go b/rlp/encoder_example_test.go index 42c1c5c89..4cd3cb867 100644 --- a/rlp/encoder_example_test.go +++ b/rlp/encoder_example_test.go @@ -14,11 +14,13 @@ // You should have received a copy of the GNU Lesser General Public License // along with the go-ethereum library. If not, see . -package rlp +package rlp_test import ( "fmt" "io" + + "github.com/ethereum/go-ethereum/rlp" ) type MyCoolType struct { @@ -28,16 +30,16 @@ type MyCoolType struct { // EncodeRLP writes x as RLP list [a, b] that omits the Name field. func (x *MyCoolType) EncodeRLP(w io.Writer) (err error) { - return Encode(w, []uint{x.a, x.b}) + return rlp.Encode(w, []uint{x.a, x.b}) } func ExampleEncoder() { var t *MyCoolType // t is nil pointer to MyCoolType - bytes, _ := EncodeToBytes(t) + bytes, _ := rlp.EncodeToBytes(t) fmt.Printf("%v → %X\n", t, bytes) t = &MyCoolType{Name: "foobar", a: 5, b: 6} - bytes, _ = EncodeToBytes(t) + bytes, _ = rlp.EncodeToBytes(t) fmt.Printf("%v → %X\n", t, bytes) // Output: diff --git a/rlp/internal/rlpstruct/rlpstruct.go b/rlp/internal/rlpstruct/rlpstruct.go new file mode 100644 index 000000000..1ebaa960e --- /dev/null +++ b/rlp/internal/rlpstruct/rlpstruct.go @@ -0,0 +1,213 @@ +// Copyright 2021 The go-ethereum Authors +// This file is part of the go-ethereum library. +// +// The go-ethereum library is free software: you can redistribute it and/or modify +// it under the terms of the GNU Lesser General Public License as published by +// the Free Software Foundation, either version 3 of the License, or +// (at your option) any later version. +// +// The go-ethereum library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public License +// along with the go-ethereum library. If not, see . + +// Package rlpstruct implements struct processing for RLP encoding/decoding. +// +// In particular, this package handles all rules around field filtering, +// struct tags and nil value determination. +package rlpstruct + +import ( + "fmt" + "reflect" + "strings" +) + +// Field represents a struct field. +type Field struct { + Name string + Index int + Exported bool + Type Type + Tag string +} + +// Type represents the attributes of a Go type. +type Type struct { + Name string + Kind reflect.Kind + IsEncoder bool // whether type implements rlp.Encoder + IsDecoder bool // whether type implements rlp.Decoder + Elem *Type // non-nil for Kind values of Ptr, Slice, Array +} + +// defaultNilValue determines whether a nil pointer to t encodes/decodes +// as an empty string or empty list. +func (t Type) DefaultNilValue() NilKind { + k := t.Kind + if isUint(k) || k == reflect.String || k == reflect.Bool || isByteArray(t) { + return NilKindString + } + return NilKindList +} + +// NilKind is the RLP value encoded in place of nil pointers. +type NilKind uint8 + +const ( + NilKindString NilKind = 0x80 + NilKindList NilKind = 0xC0 +) + +// Tags represents struct tags. +type Tags struct { + // rlp:"nil" controls whether empty input results in a nil pointer. + // nilKind is the kind of empty value allowed for the field. + NilKind NilKind + NilOK bool + + // rlp:"optional" allows for a field to be missing in the input list. + // If this is set, all subsequent fields must also be optional. + Optional bool + + // rlp:"tail" controls whether this field swallows additional list elements. It can + // only be set for the last field, which must be of slice type. + Tail bool + + // rlp:"-" ignores fields. + Ignored bool +} + +// TagError is raised for invalid struct tags. +type TagError struct { + StructType string + + // These are set by this package. + Field string + Tag string + Err string +} + +func (e TagError) Error() string { + field := "field " + e.Field + if e.StructType != "" { + field = e.StructType + "." + e.Field + } + return fmt.Sprintf("rlp: invalid struct tag %q for %s (%s)", e.Tag, field, e.Err) +} + +// ProcessFields filters the given struct fields, returning only fields +// that should be considered for encoding/decoding. +func ProcessFields(allFields []Field) ([]Field, []Tags, error) { + lastPublic := lastPublicField(allFields) + + // Gather all exported fields and their tags. + var fields []Field + var tags []Tags + for _, field := range allFields { + if !field.Exported { + continue + } + ts, err := parseTag(field, lastPublic) + if err != nil { + return nil, nil, err + } + if ts.Ignored { + continue + } + fields = append(fields, field) + tags = append(tags, ts) + } + + // Verify optional field consistency. If any optional field exists, + // all fields after it must also be optional. Note: optional + tail + // is supported. + var anyOptional bool + var firstOptionalName string + for i, ts := range tags { + name := fields[i].Name + if ts.Optional || ts.Tail { + if !anyOptional { + firstOptionalName = name + } + anyOptional = true + } else { + if anyOptional { + msg := fmt.Sprintf("must be optional because preceding field %q is optional", firstOptionalName) + return nil, nil, TagError{Field: name, Err: msg} + } + } + } + return fields, tags, nil +} + +func parseTag(field Field, lastPublic int) (Tags, error) { + name := field.Name + tag := reflect.StructTag(field.Tag) + var ts Tags + for _, t := range strings.Split(tag.Get("rlp"), ",") { + switch t = strings.TrimSpace(t); t { + case "": + // empty tag is allowed for some reason + case "-": + ts.Ignored = true + case "nil", "nilString", "nilList": + ts.NilOK = true + if field.Type.Kind != reflect.Ptr { + return ts, TagError{Field: name, Tag: t, Err: "field is not a pointer"} + } + switch t { + case "nil": + ts.NilKind = field.Type.Elem.DefaultNilValue() + case "nilString": + ts.NilKind = NilKindString + case "nilList": + ts.NilKind = NilKindList + } + case "optional": + ts.Optional = true + if ts.Tail { + return ts, TagError{Field: name, Tag: t, Err: `also has "tail" tag`} + } + case "tail": + ts.Tail = true + if field.Index != lastPublic { + return ts, TagError{Field: name, Tag: t, Err: "must be on last field"} + } + if ts.Optional { + return ts, TagError{Field: name, Tag: t, Err: `also has "optional" tag`} + } + if field.Type.Kind != reflect.Slice { + return ts, TagError{Field: name, Tag: t, Err: "field type is not slice"} + } + default: + return ts, TagError{Field: name, Tag: t, Err: "unknown tag"} + } + } + return ts, nil +} + +func lastPublicField(fields []Field) int { + last := 0 + for _, f := range fields { + if f.Exported { + last = f.Index + } + } + return last +} + +func isUint(k reflect.Kind) bool { + return k >= reflect.Uint && k <= reflect.Uintptr +} + +func isByte(typ Type) bool { + return typ.Kind == reflect.Uint8 && !typ.IsEncoder +} + +func isByteArray(typ Type) bool { + return (typ.Kind == reflect.Slice || typ.Kind == reflect.Array) && isByte(*typ.Elem) +} diff --git a/rlp/rlpgen/gen.go b/rlp/rlpgen/gen.go new file mode 100644 index 000000000..b36b26947 --- /dev/null +++ b/rlp/rlpgen/gen.go @@ -0,0 +1,735 @@ +package main + +import ( + "bytes" + "fmt" + "go/format" + "go/types" + "sort" + + "github.com/ethereum/go-ethereum/rlp/internal/rlpstruct" +) + +// buildContext keeps the data needed for make*Op. +type buildContext struct { + topType *types.Named // the type we're creating methods for + + encoderIface *types.Interface + decoderIface *types.Interface + rawValueType *types.Named + + typeToStructCache map[types.Type]*rlpstruct.Type +} + +func newBuildContext(packageRLP *types.Package) *buildContext { + enc := packageRLP.Scope().Lookup("Encoder").Type().Underlying() + dec := packageRLP.Scope().Lookup("Decoder").Type().Underlying() + rawv := packageRLP.Scope().Lookup("RawValue").Type() + return &buildContext{ + typeToStructCache: make(map[types.Type]*rlpstruct.Type), + encoderIface: enc.(*types.Interface), + decoderIface: dec.(*types.Interface), + rawValueType: rawv.(*types.Named), + } +} + +func (bctx *buildContext) isEncoder(typ types.Type) bool { + return types.Implements(typ, bctx.encoderIface) +} + +func (bctx *buildContext) isDecoder(typ types.Type) bool { + return types.Implements(typ, bctx.decoderIface) +} + +// typeToStructType converts typ to rlpstruct.Type. +func (bctx *buildContext) typeToStructType(typ types.Type) *rlpstruct.Type { + if prev := bctx.typeToStructCache[typ]; prev != nil { + return prev // short-circuit for recursive types. + } + + // Resolve named types to their underlying type, but keep the name. + name := types.TypeString(typ, nil) + for { + utype := typ.Underlying() + if utype == typ { + break + } + typ = utype + } + + // Create the type and store it in cache. + t := &rlpstruct.Type{ + Name: name, + Kind: typeReflectKind(typ), + IsEncoder: bctx.isEncoder(typ), + IsDecoder: bctx.isDecoder(typ), + } + bctx.typeToStructCache[typ] = t + + // Assign element type. + switch typ.(type) { + case *types.Array, *types.Slice, *types.Pointer: + etype := typ.(interface{ Elem() types.Type }).Elem() + t.Elem = bctx.typeToStructType(etype) + } + return t +} + +// genContext is passed to the gen* methods of op when generating +// the output code. It tracks packages to be imported by the output +// file and assigns unique names of temporary variables. +type genContext struct { + inPackage *types.Package + imports map[string]struct{} + tempCounter int +} + +func newGenContext(inPackage *types.Package) *genContext { + return &genContext{ + inPackage: inPackage, + imports: make(map[string]struct{}), + } +} + +func (ctx *genContext) temp() string { + v := fmt.Sprintf("_tmp%d", ctx.tempCounter) + ctx.tempCounter++ + return v +} + +func (ctx *genContext) resetTemp() { + ctx.tempCounter = 0 +} + +func (ctx *genContext) addImport(path string) { + if path == ctx.inPackage.Path() { + return // avoid importing the package that we're generating in. + } + // TODO: renaming? + ctx.imports[path] = struct{}{} +} + +// importsList returns all packages that need to be imported. +func (ctx *genContext) importsList() []string { + imp := make([]string, 0, len(ctx.imports)) + for k := range ctx.imports { + imp = append(imp, k) + } + sort.Strings(imp) + return imp +} + +// qualify is the types.Qualifier used for printing types. +func (ctx *genContext) qualify(pkg *types.Package) string { + if pkg.Path() == ctx.inPackage.Path() { + return "" + } + ctx.addImport(pkg.Path()) + // TODO: renaming? + return pkg.Name() +} + +type op interface { + // genWrite creates the encoder. The generated code should write v, + // which is any Go expression, to the rlp.EncoderBuffer 'w'. + genWrite(ctx *genContext, v string) string + + // genDecode creates the decoder. The generated code should read + // a value from the rlp.Stream 'dec' and store it to dst. + genDecode(ctx *genContext) (string, string) +} + +// basicOp handles basic types bool, uint*, string. +type basicOp struct { + typ types.Type + writeMethod string // calle write the value + writeArgType types.Type // parameter type of writeMethod + decMethod string + decResultType types.Type // return type of decMethod + decUseBitSize bool // if true, result bit size is appended to decMethod +} + +func (*buildContext) makeBasicOp(typ *types.Basic) (op, error) { + op := basicOp{typ: typ} + kind := typ.Kind() + switch { + case kind == types.Bool: + op.writeMethod = "WriteBool" + op.writeArgType = types.Typ[types.Bool] + op.decMethod = "Bool" + op.decResultType = types.Typ[types.Bool] + case kind >= types.Uint8 && kind <= types.Uint64: + op.writeMethod = "WriteUint64" + op.writeArgType = types.Typ[types.Uint64] + op.decMethod = "Uint" + op.decResultType = typ + op.decUseBitSize = true + case kind == types.String: + op.writeMethod = "WriteString" + op.writeArgType = types.Typ[types.String] + op.decMethod = "String" + op.decResultType = types.Typ[types.String] + default: + return nil, fmt.Errorf("unhandled basic type: %v", typ) + } + return op, nil +} + +func (*buildContext) makeByteSliceOp(typ *types.Slice) op { + if !isByte(typ.Elem()) { + panic("non-byte slice type in makeByteSliceOp") + } + bslice := types.NewSlice(types.Typ[types.Uint8]) + return basicOp{ + typ: typ, + writeMethod: "WriteBytes", + writeArgType: bslice, + decMethod: "Bytes", + decResultType: bslice, + } +} + +func (bctx *buildContext) makeRawValueOp() op { + bslice := types.NewSlice(types.Typ[types.Uint8]) + return basicOp{ + typ: bctx.rawValueType, + writeMethod: "Write", + writeArgType: bslice, + decMethod: "Raw", + decResultType: bslice, + } +} + +func (op basicOp) writeNeedsConversion() bool { + return !types.AssignableTo(op.typ, op.writeArgType) +} + +func (op basicOp) decodeNeedsConversion() bool { + return !types.AssignableTo(op.decResultType, op.typ) +} + +func (op basicOp) genWrite(ctx *genContext, v string) string { + if op.writeNeedsConversion() { + v = fmt.Sprintf("%s(%s)", op.writeArgType, v) + } + return fmt.Sprintf("w.%s(%s)\n", op.writeMethod, v) +} + +func (op basicOp) genDecode(ctx *genContext) (string, string) { + var ( + resultV = ctx.temp() + result = resultV + method = op.decMethod + ) + if op.decUseBitSize { + // Note: For now, this only works for platform-independent integer + // sizes. makeBasicOp forbids the platform-dependent types. + var sizes types.StdSizes + method = fmt.Sprintf("%s%d", op.decMethod, sizes.Sizeof(op.typ)*8) + } + + // Call the decoder method. + var b bytes.Buffer + fmt.Fprintf(&b, "%s, err := dec.%s()\n", resultV, method) + fmt.Fprintf(&b, "if err != nil { return err }\n") + if op.decodeNeedsConversion() { + conv := ctx.temp() + fmt.Fprintf(&b, "%s := %s(%s)\n", conv, types.TypeString(op.typ, ctx.qualify), resultV) + result = conv + } + return result, b.String() +} + +// byteArrayOp handles [...]byte. +type byteArrayOp struct { + typ types.Type + name types.Type // name != typ for named byte array types (e.g. common.Address) +} + +func (bctx *buildContext) makeByteArrayOp(name *types.Named, typ *types.Array) byteArrayOp { + nt := types.Type(name) + if name == nil { + nt = typ + } + return byteArrayOp{typ, nt} +} + +func (op byteArrayOp) genWrite(ctx *genContext, v string) string { + return fmt.Sprintf("w.WriteBytes(%s[:])\n", v) +} + +func (op byteArrayOp) genDecode(ctx *genContext) (string, string) { + var resultV = ctx.temp() + + var b bytes.Buffer + fmt.Fprintf(&b, "var %s %s\n", resultV, types.TypeString(op.name, ctx.qualify)) + fmt.Fprintf(&b, "if err := dec.ReadBytes(%s[:]); err != nil { return err }\n", resultV) + return resultV, b.String() +} + +// bigIntNoPtrOp handles non-pointer big.Int. +// This exists because big.Int has it's own decoder operation on rlp.Stream, +// but the decode method returns *big.Int, so it needs to be dereferenced. +type bigIntOp struct { + pointer bool +} + +func (op bigIntOp) genWrite(ctx *genContext, v string) string { + var b bytes.Buffer + + fmt.Fprintf(&b, "if %s.Sign() == -1 {\n", v) + fmt.Fprintf(&b, " return rlp.ErrNegativeBigInt\n") + fmt.Fprintf(&b, "}\n") + dst := v + if !op.pointer { + dst = "&" + v + } + fmt.Fprintf(&b, "w.WriteBigInt(%s)\n", dst) + + // Wrap with nil check. + if op.pointer { + code := b.String() + b.Reset() + fmt.Fprintf(&b, "if %s == nil {\n", v) + fmt.Fprintf(&b, " w.Write(rlp.EmptyString)") + fmt.Fprintf(&b, "} else {\n") + fmt.Fprint(&b, code) + fmt.Fprintf(&b, "}\n") + } + + return b.String() +} + +func (op bigIntOp) genDecode(ctx *genContext) (string, string) { + var resultV = ctx.temp() + + var b bytes.Buffer + fmt.Fprintf(&b, "%s, err := dec.BigInt()\n", resultV) + fmt.Fprintf(&b, "if err != nil { return err }\n") + + result := resultV + if !op.pointer { + result = "(*" + resultV + ")" + } + return result, b.String() +} + +// encoderDecoderOp handles rlp.Encoder and rlp.Decoder. +// In order to be used with this, the type must implement both interfaces. +// This restriction may be lifted in the future by creating separate ops for +// encoding and decoding. +type encoderDecoderOp struct { + typ types.Type +} + +func (op encoderDecoderOp) genWrite(ctx *genContext, v string) string { + return fmt.Sprintf("if err := %s.EncodeRLP(w); err != nil { return err }\n", v) +} + +func (op encoderDecoderOp) genDecode(ctx *genContext) (string, string) { + // DecodeRLP must have pointer receiver, and this is verified in makeOp. + etyp := op.typ.(*types.Pointer).Elem() + var resultV = ctx.temp() + + var b bytes.Buffer + fmt.Fprintf(&b, "%s := new(%s)\n", resultV, types.TypeString(etyp, ctx.qualify)) + fmt.Fprintf(&b, "if err := %s.DecodeRLP(dec); err != nil { return err }\n", resultV) + return resultV, b.String() +} + +// ptrOp handles pointer types. +type ptrOp struct { + elemTyp types.Type + elem op + nilOK bool + nilValue rlpstruct.NilKind +} + +func (bctx *buildContext) makePtrOp(elemTyp types.Type, tags rlpstruct.Tags) (op, error) { + elemOp, err := bctx.makeOp(nil, elemTyp, rlpstruct.Tags{}) + if err != nil { + return nil, err + } + op := ptrOp{elemTyp: elemTyp, elem: elemOp} + + // Determine nil value. + if tags.NilOK { + op.nilOK = true + op.nilValue = tags.NilKind + } else { + styp := bctx.typeToStructType(elemTyp) + op.nilValue = styp.DefaultNilValue() + } + return op, nil +} + +func (op ptrOp) genWrite(ctx *genContext, v string) string { + // Note: in writer functions, accesses to v are read-only, i.e. v is any Go + // expression. To make all accesses work through the pointer, we substitute + // v with (*v). This is required for most accesses including `v`, `call(v)`, + // and `v[index]` on slices. + // + // For `v.field` and `v[:]` on arrays, the dereference operation is not required. + var vv string + _, isStruct := op.elem.(structOp) + _, isByteArray := op.elem.(byteArrayOp) + if isStruct || isByteArray { + vv = v + } else { + vv = fmt.Sprintf("(*%s)", v) + } + + var b bytes.Buffer + fmt.Fprintf(&b, "if %s == nil {\n", v) + fmt.Fprintf(&b, " w.Write([]byte{0x%X})\n", op.nilValue) + fmt.Fprintf(&b, "} else {\n") + fmt.Fprintf(&b, " %s", op.elem.genWrite(ctx, vv)) + fmt.Fprintf(&b, "}\n") + return b.String() +} + +func (op ptrOp) genDecode(ctx *genContext) (string, string) { + result, code := op.elem.genDecode(ctx) + if !op.nilOK { + // If nil pointers are not allowed, we can just decode the element. + return "&" + result, code + } + + // nil is allowed, so check the kind and size first. + // If size is zero and kind matches the nilKind of the type, + // the value decodes as a nil pointer. + var ( + resultV = ctx.temp() + kindV = ctx.temp() + sizeV = ctx.temp() + wantKind string + ) + if op.nilValue == rlpstruct.NilKindList { + wantKind = "rlp.List" + } else { + wantKind = "rlp.String" + } + var b bytes.Buffer + fmt.Fprintf(&b, "var %s %s\n", resultV, types.TypeString(types.NewPointer(op.elemTyp), ctx.qualify)) + fmt.Fprintf(&b, "if %s, %s, err := dec.Kind(); err != nil {\n", kindV, sizeV) + fmt.Fprintf(&b, " return err\n") + fmt.Fprintf(&b, "} else if %s != 0 || %s != %s {\n", sizeV, kindV, wantKind) + fmt.Fprint(&b, code) + fmt.Fprintf(&b, " %s = &%s\n", resultV, result) + fmt.Fprintf(&b, "}\n") + return resultV, b.String() +} + +// structOp handles struct types. +type structOp struct { + named *types.Named + typ *types.Struct + fields []*structField + optionalFields []*structField +} + +type structField struct { + name string + typ types.Type + elem op +} + +func (bctx *buildContext) makeStructOp(named *types.Named, typ *types.Struct) (op, error) { + // Convert fields to []rlpstruct.Field. + var allStructFields []rlpstruct.Field + for i := 0; i < typ.NumFields(); i++ { + f := typ.Field(i) + allStructFields = append(allStructFields, rlpstruct.Field{ + Name: f.Name(), + Exported: f.Exported(), + Index: i, + Tag: typ.Tag(i), + Type: *bctx.typeToStructType(f.Type()), + }) + } + + // Filter/validate fields. + fields, tags, err := rlpstruct.ProcessFields(allStructFields) + if err != nil { + return nil, err + } + + // Create field ops. + var op = structOp{named: named, typ: typ} + for i, field := range fields { + // Advanced struct tags are not supported yet. + tag := tags[i] + if err := checkUnsupportedTags(field.Name, tag); err != nil { + return nil, err + } + typ := typ.Field(field.Index).Type() + elem, err := bctx.makeOp(nil, typ, tags[i]) + if err != nil { + return nil, fmt.Errorf("field %s: %v", field.Name, err) + } + f := &structField{name: field.Name, typ: typ, elem: elem} + if tag.Optional { + op.optionalFields = append(op.optionalFields, f) + } else { + op.fields = append(op.fields, f) + } + } + return op, nil +} + +func checkUnsupportedTags(field string, tag rlpstruct.Tags) error { + if tag.Tail { + return fmt.Errorf(`field %s has unsupported struct tag "tail"`, field) + } + return nil +} + +func (op structOp) genWrite(ctx *genContext, v string) string { + var b bytes.Buffer + var listMarker = ctx.temp() + fmt.Fprintf(&b, "%s := w.List()\n", listMarker) + for _, field := range op.fields { + selector := v + "." + field.name + fmt.Fprint(&b, field.elem.genWrite(ctx, selector)) + } + op.writeOptionalFields(&b, ctx, v) + fmt.Fprintf(&b, "w.ListEnd(%s)\n", listMarker) + return b.String() +} + +func (op structOp) writeOptionalFields(b *bytes.Buffer, ctx *genContext, v string) { + if len(op.optionalFields) == 0 { + return + } + // First check zero-ness of all optional fields. + var zeroV = make([]string, len(op.optionalFields)) + for i, field := range op.optionalFields { + selector := v + "." + field.name + zeroV[i] = ctx.temp() + fmt.Fprintf(b, "%s := %s\n", zeroV[i], nonZeroCheck(selector, field.typ, ctx.qualify)) + } + // Now write the fields. + for i, field := range op.optionalFields { + selector := v + "." + field.name + cond := "" + for j := i; j < len(op.optionalFields); j++ { + if j > i { + cond += " || " + } + cond += zeroV[j] + } + fmt.Fprintf(b, "if %s {\n", cond) + fmt.Fprint(b, field.elem.genWrite(ctx, selector)) + fmt.Fprintf(b, "}\n") + } +} + +func (op structOp) genDecode(ctx *genContext) (string, string) { + // Get the string representation of the type. + // Here, named types are handled separately because the output + // would contain a copy of the struct definition otherwise. + var typeName string + if op.named != nil { + typeName = types.TypeString(op.named, ctx.qualify) + } else { + typeName = types.TypeString(op.typ, ctx.qualify) + } + + // Create struct object. + var resultV = ctx.temp() + var b bytes.Buffer + fmt.Fprintf(&b, "var %s %s\n", resultV, typeName) + + // Decode fields. + fmt.Fprintf(&b, "{\n") + fmt.Fprintf(&b, "if _, err := dec.List(); err != nil { return err }\n") + for _, field := range op.fields { + result, code := field.elem.genDecode(ctx) + fmt.Fprintf(&b, "// %s:\n", field.name) + fmt.Fprint(&b, code) + fmt.Fprintf(&b, "%s.%s = %s\n", resultV, field.name, result) + } + op.decodeOptionalFields(&b, ctx, resultV) + fmt.Fprintf(&b, "if err := dec.ListEnd(); err != nil { return err }\n") + fmt.Fprintf(&b, "}\n") + return resultV, b.String() +} + +func (op structOp) decodeOptionalFields(b *bytes.Buffer, ctx *genContext, resultV string) { + var suffix bytes.Buffer + for _, field := range op.optionalFields { + result, code := field.elem.genDecode(ctx) + fmt.Fprintf(b, "// %s:\n", field.name) + fmt.Fprintf(b, "if dec.MoreDataInList() {\n") + fmt.Fprint(b, code) + fmt.Fprintf(b, "%s.%s = %s\n", resultV, field.name, result) + fmt.Fprintf(&suffix, "}\n") + } + suffix.WriteTo(b) +} + +// sliceOp handles slice types. +type sliceOp struct { + typ *types.Slice + elemOp op +} + +func (bctx *buildContext) makeSliceOp(typ *types.Slice) (op, error) { + elemOp, err := bctx.makeOp(nil, typ.Elem(), rlpstruct.Tags{}) + if err != nil { + return nil, err + } + return sliceOp{typ: typ, elemOp: elemOp}, nil +} + +func (op sliceOp) genWrite(ctx *genContext, v string) string { + var ( + listMarker = ctx.temp() // holds return value of w.List() + iterElemV = ctx.temp() // iteration variable + elemCode = op.elemOp.genWrite(ctx, iterElemV) + ) + + var b bytes.Buffer + fmt.Fprintf(&b, "%s := w.List()\n", listMarker) + fmt.Fprintf(&b, "for _, %s := range %s {\n", iterElemV, v) + fmt.Fprint(&b, elemCode) + fmt.Fprintf(&b, "}\n") + fmt.Fprintf(&b, "w.ListEnd(%s)\n", listMarker) + return b.String() +} + +func (op sliceOp) genDecode(ctx *genContext) (string, string) { + var sliceV = ctx.temp() // holds the output slice + elemResult, elemCode := op.elemOp.genDecode(ctx) + + var b bytes.Buffer + fmt.Fprintf(&b, "var %s %s\n", sliceV, types.TypeString(op.typ, ctx.qualify)) + fmt.Fprintf(&b, "if _, err := dec.List(); err != nil { return err }\n") + fmt.Fprintf(&b, "for dec.MoreDataInList() {\n") + fmt.Fprintf(&b, " %s", elemCode) + fmt.Fprintf(&b, " %s = append(%s, %s)\n", sliceV, sliceV, elemResult) + fmt.Fprintf(&b, "}\n") + fmt.Fprintf(&b, "if err := dec.ListEnd(); err != nil { return err }\n") + return sliceV, b.String() +} + +func (bctx *buildContext) makeOp(name *types.Named, typ types.Type, tags rlpstruct.Tags) (op, error) { + switch typ := typ.(type) { + case *types.Named: + if isBigInt(typ) { + return bigIntOp{}, nil + } + if typ == bctx.rawValueType { + return bctx.makeRawValueOp(), nil + } + if bctx.isDecoder(typ) { + return nil, fmt.Errorf("type %v implements rlp.Decoder with non-pointer receiver", typ) + } + // TODO: same check for encoder? + return bctx.makeOp(typ, typ.Underlying(), tags) + case *types.Pointer: + if isBigInt(typ.Elem()) { + return bigIntOp{pointer: true}, nil + } + // Encoder/Decoder interfaces. + if bctx.isEncoder(typ) { + if bctx.isDecoder(typ) { + return encoderDecoderOp{typ}, nil + } + return nil, fmt.Errorf("type %v implements rlp.Encoder but not rlp.Decoder", typ) + } + if bctx.isDecoder(typ) { + return nil, fmt.Errorf("type %v implements rlp.Decoder but not rlp.Encoder", typ) + } + // Default pointer handling. + return bctx.makePtrOp(typ.Elem(), tags) + case *types.Basic: + return bctx.makeBasicOp(typ) + case *types.Struct: + return bctx.makeStructOp(name, typ) + case *types.Slice: + etyp := typ.Elem() + if isByte(etyp) && !bctx.isEncoder(etyp) { + return bctx.makeByteSliceOp(typ), nil + } + return bctx.makeSliceOp(typ) + case *types.Array: + etyp := typ.Elem() + if isByte(etyp) && !bctx.isEncoder(etyp) { + return bctx.makeByteArrayOp(name, typ), nil + } + return nil, fmt.Errorf("unhandled array type: %v", typ) + default: + return nil, fmt.Errorf("unhandled type: %v", typ) + } +} + +// generateDecoder generates the DecodeRLP method on 'typ'. +func generateDecoder(ctx *genContext, typ string, op op) []byte { + ctx.resetTemp() + ctx.addImport(pathOfPackageRLP) + + result, code := op.genDecode(ctx) + var b bytes.Buffer + fmt.Fprintf(&b, "func (obj *%s) DecodeRLP(dec *rlp.Stream) error {\n", typ) + fmt.Fprint(&b, code) + fmt.Fprintf(&b, " *obj = %s\n", result) + fmt.Fprintf(&b, " return nil\n") + fmt.Fprintf(&b, "}\n") + return b.Bytes() +} + +// generateEncoder generates the EncodeRLP method on 'typ'. +func generateEncoder(ctx *genContext, typ string, op op) []byte { + ctx.resetTemp() + ctx.addImport("io") + ctx.addImport(pathOfPackageRLP) + + var b bytes.Buffer + fmt.Fprintf(&b, "func (obj *%s) EncodeRLP(_w io.Writer) error {\n", typ) + fmt.Fprintf(&b, " w := rlp.NewEncoderBuffer(_w)\n") + fmt.Fprint(&b, op.genWrite(ctx, "obj")) + fmt.Fprintf(&b, " return w.Flush()\n") + fmt.Fprintf(&b, "}\n") + return b.Bytes() +} + +func (bctx *buildContext) generate(typ *types.Named, encoder, decoder bool) ([]byte, error) { + bctx.topType = typ + + pkg := typ.Obj().Pkg() + op, err := bctx.makeOp(nil, typ, rlpstruct.Tags{}) + if err != nil { + return nil, err + } + + var ( + ctx = newGenContext(pkg) + encSource []byte + decSource []byte + ) + if encoder { + encSource = generateEncoder(ctx, typ.Obj().Name(), op) + } + if decoder { + decSource = generateDecoder(ctx, typ.Obj().Name(), op) + } + + var b bytes.Buffer + fmt.Fprintf(&b, "package %s\n\n", pkg.Name()) + for _, imp := range ctx.importsList() { + fmt.Fprintf(&b, "import %q\n", imp) + } + if encoder { + fmt.Fprintln(&b) + b.Write(encSource) + } + if decoder { + fmt.Fprintln(&b) + b.Write(decSource) + } + + source := b.Bytes() + // fmt.Println(string(source)) + return format.Source(source) +} diff --git a/rlp/rlpgen/gen_test.go b/rlp/rlpgen/gen_test.go new file mode 100644 index 000000000..9940db188 --- /dev/null +++ b/rlp/rlpgen/gen_test.go @@ -0,0 +1,92 @@ +package main + +import ( + "bytes" + "fmt" + "go/ast" + "go/importer" + "go/parser" + "go/token" + "go/types" + "io/ioutil" + "os" + "path/filepath" + "testing" +) + +// Package RLP is loaded only once and reused for all tests. +var ( + testFset = token.NewFileSet() + testImporter = importer.ForCompiler(testFset, "source", nil).(types.ImporterFrom) + testPackageRLP *types.Package +) + +func init() { + cwd, err := os.Getwd() + if err != nil { + panic(err) + } + testPackageRLP, err = testImporter.ImportFrom(pathOfPackageRLP, cwd, 0) + if err != nil { + panic(fmt.Errorf("can't load package RLP: %v", err)) + } +} + +var tests = []string{"uints", "nil", "rawvalue", "optional", "bigint"} + +func TestOutput(t *testing.T) { + for _, test := range tests { + test := test + t.Run(test, func(t *testing.T) { + inputFile := filepath.Join("testdata", test+".in.txt") + outputFile := filepath.Join("testdata", test+".out.txt") + bctx, typ, err := loadTestSource(inputFile, "Test") + if err != nil { + t.Fatal("error loading test source:", err) + } + output, err := bctx.generate(typ, true, true) + if err != nil { + t.Fatal("error in generate:", err) + } + + // Set this environment variable to regenerate the test outputs. + if os.Getenv("WRITE_TEST_FILES") != "" { + ioutil.WriteFile(outputFile, output, 0644) + } + + // Check if output matches. + wantOutput, err := ioutil.ReadFile(outputFile) + if err != nil { + t.Fatal("error loading expected test output:", err) + } + if !bytes.Equal(output, wantOutput) { + t.Fatal("output mismatch:\n", string(output)) + } + }) + } +} + +func loadTestSource(file string, typeName string) (*buildContext, *types.Named, error) { + // Load the test input. + content, err := ioutil.ReadFile(file) + if err != nil { + return nil, nil, err + } + f, err := parser.ParseFile(testFset, file, content, 0) + if err != nil { + return nil, nil, err + } + conf := types.Config{Importer: testImporter} + pkg, err := conf.Check("test", testFset, []*ast.File{f}, nil) + if err != nil { + return nil, nil, err + } + + // Find the test struct. + bctx := newBuildContext(testPackageRLP) + typ, err := lookupStructType(pkg.Scope(), typeName) + if err != nil { + return nil, nil, fmt.Errorf("can't find type %s: %v", typeName, err) + } + return bctx, typ, nil +} diff --git a/rlp/rlpgen/main.go b/rlp/rlpgen/main.go new file mode 100644 index 000000000..5b240bfd8 --- /dev/null +++ b/rlp/rlpgen/main.go @@ -0,0 +1,148 @@ +// Copyright 2021 The go-ethereum Authors +// This file is part of the go-ethereum library. +// +// The go-ethereum library is free software: you can redistribute it and/or modify +// it under the terms of the GNU Lesser General Public License as published by +// the Free Software Foundation, either version 3 of the License, or +// (at your option) any later version. +// +// The go-ethereum library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU Lesser General Public License for more details. +// +// You should have received a copy of the GNU Lesser General Public License +// along with the go-ethereum library. If not, see . + +package main + +import ( + "bytes" + "errors" + "flag" + "fmt" + "go/types" + "io/ioutil" + "os" + + "golang.org/x/tools/go/packages" +) + +const pathOfPackageRLP = "github.com/ethereum/go-ethereum/rlp" + +func main() { + var ( + pkgdir = flag.String("dir", ".", "input package") + output = flag.String("out", "-", "output file (default is stdout)") + genEncoder = flag.Bool("encoder", true, "generate EncodeRLP?") + genDecoder = flag.Bool("decoder", false, "generate DecodeRLP?") + typename = flag.String("type", "", "type to generate methods for") + ) + flag.Parse() + + cfg := Config{ + Dir: *pkgdir, + Type: *typename, + GenerateEncoder: *genEncoder, + GenerateDecoder: *genDecoder, + } + code, err := cfg.process() + if err != nil { + fatal(err) + } + if *output == "-" { + os.Stdout.Write(code) + } else if err := ioutil.WriteFile(*output, code, 0644); err != nil { + fatal(err) + } +} + +func fatal(args ...interface{}) { + fmt.Fprintln(os.Stderr, args...) + os.Exit(1) +} + +type Config struct { + Dir string // input package directory + Type string + + GenerateEncoder bool + GenerateDecoder bool +} + +// process generates the Go code. +func (cfg *Config) process() (code []byte, err error) { + // Load packages. + pcfg := &packages.Config{ + Mode: packages.NeedName | packages.NeedTypes | packages.NeedImports | packages.NeedDeps, + Dir: cfg.Dir, + BuildFlags: []string{"-tags", "norlpgen"}, + } + ps, err := packages.Load(pcfg, pathOfPackageRLP, ".") + if err != nil { + return nil, err + } + if len(ps) == 0 { + return nil, fmt.Errorf("no Go package found in %s", cfg.Dir) + } + packages.PrintErrors(ps) + + // Find the packages that were loaded. + var ( + pkg *types.Package + packageRLP *types.Package + ) + for _, p := range ps { + if len(p.Errors) > 0 { + return nil, fmt.Errorf("package %s has errors", p.PkgPath) + } + if p.PkgPath == pathOfPackageRLP { + packageRLP = p.Types + } else { + pkg = p.Types + } + } + bctx := newBuildContext(packageRLP) + + // Find the type and generate. + typ, err := lookupStructType(pkg.Scope(), cfg.Type) + if err != nil { + return nil, fmt.Errorf("can't find %s in %s: %v", typ, pkg, err) + } + code, err = bctx.generate(typ, cfg.GenerateEncoder, cfg.GenerateDecoder) + if err != nil { + return nil, err + } + + // Add build comments. + // This is done here to avoid processing these lines with gofmt. + var header bytes.Buffer + fmt.Fprint(&header, "// Code generated by rlpgen. DO NOT EDIT.\n\n") + fmt.Fprint(&header, "//go:build !norlpgen\n") + fmt.Fprint(&header, "// +build !norlpgen\n\n") + return append(header.Bytes(), code...), nil +} + +func lookupStructType(scope *types.Scope, name string) (*types.Named, error) { + typ, err := lookupType(scope, name) + if err != nil { + return nil, err + } + _, ok := typ.Underlying().(*types.Struct) + if !ok { + return nil, errors.New("not a struct type") + } + return typ, nil +} + +func lookupType(scope *types.Scope, name string) (*types.Named, error) { + obj := scope.Lookup(name) + if obj == nil { + return nil, errors.New("no such identifier") + } + typ, ok := obj.(*types.TypeName) + if !ok { + return nil, errors.New("not a type") + } + return typ.Type().(*types.Named), nil +} diff --git a/rlp/rlpgen/testdata/bigint.in.txt b/rlp/rlpgen/testdata/bigint.in.txt new file mode 100644 index 000000000..d23d84a28 --- /dev/null +++ b/rlp/rlpgen/testdata/bigint.in.txt @@ -0,0 +1,10 @@ +// -*- mode: go -*- + +package test + +import "math/big" + +type Test struct { + Int *big.Int + IntNoPtr big.Int +} diff --git a/rlp/rlpgen/testdata/bigint.out.txt b/rlp/rlpgen/testdata/bigint.out.txt new file mode 100644 index 000000000..f54d1faa1 --- /dev/null +++ b/rlp/rlpgen/testdata/bigint.out.txt @@ -0,0 +1,49 @@ +package test + +import "github.com/ethereum/go-ethereum/rlp" +import "io" + +func (obj *Test) EncodeRLP(_w io.Writer) error { + w := rlp.NewEncoderBuffer(_w) + _tmp0 := w.List() + if obj.Int == nil { + w.Write(rlp.EmptyString) + } else { + if obj.Int.Sign() == -1 { + return rlp.ErrNegativeBigInt + } + w.WriteBigInt(obj.Int) + } + if obj.IntNoPtr.Sign() == -1 { + return rlp.ErrNegativeBigInt + } + w.WriteBigInt(&obj.IntNoPtr) + w.ListEnd(_tmp0) + return w.Flush() +} + +func (obj *Test) DecodeRLP(dec *rlp.Stream) error { + var _tmp0 Test + { + if _, err := dec.List(); err != nil { + return err + } + // Int: + _tmp1, err := dec.BigInt() + if err != nil { + return err + } + _tmp0.Int = _tmp1 + // IntNoPtr: + _tmp2, err := dec.BigInt() + if err != nil { + return err + } + _tmp0.IntNoPtr = (*_tmp2) + if err := dec.ListEnd(); err != nil { + return err + } + } + *obj = _tmp0 + return nil +} diff --git a/rlp/rlpgen/testdata/nil.in.txt b/rlp/rlpgen/testdata/nil.in.txt new file mode 100644 index 000000000..a28ff3448 --- /dev/null +++ b/rlp/rlpgen/testdata/nil.in.txt @@ -0,0 +1,30 @@ +// -*- mode: go -*- + +package test + +type Aux struct{ + A uint32 +} + +type Test struct{ + Uint8 *byte `rlp:"nil"` + Uint8List *byte `rlp:"nilList"` + + Uint32 *uint32 `rlp:"nil"` + Uint32List *uint32 `rlp:"nilList"` + + Uint64 *uint64 `rlp:"nil"` + Uint64List *uint64 `rlp:"nilList"` + + String *string `rlp:"nil"` + StringList *string `rlp:"nilList"` + + ByteArray *[3]byte `rlp:"nil"` + ByteArrayList *[3]byte `rlp:"nilList"` + + ByteSlice *[]byte `rlp:"nil"` + ByteSliceList *[]byte `rlp:"nilList"` + + Struct *Aux `rlp:"nil"` + StructString *Aux `rlp:"nilString"` +} diff --git a/rlp/rlpgen/testdata/nil.out.txt b/rlp/rlpgen/testdata/nil.out.txt new file mode 100644 index 000000000..e0d5dceba --- /dev/null +++ b/rlp/rlpgen/testdata/nil.out.txt @@ -0,0 +1,289 @@ +package test + +import "github.com/ethereum/go-ethereum/rlp" +import "io" + +func (obj *Test) EncodeRLP(_w io.Writer) error { + w := rlp.NewEncoderBuffer(_w) + _tmp0 := w.List() + if obj.Uint8 == nil { + w.Write([]byte{0x80}) + } else { + w.WriteUint64(uint64((*obj.Uint8))) + } + if obj.Uint8List == nil { + w.Write([]byte{0xC0}) + } else { + w.WriteUint64(uint64((*obj.Uint8List))) + } + if obj.Uint32 == nil { + w.Write([]byte{0x80}) + } else { + w.WriteUint64(uint64((*obj.Uint32))) + } + if obj.Uint32List == nil { + w.Write([]byte{0xC0}) + } else { + w.WriteUint64(uint64((*obj.Uint32List))) + } + if obj.Uint64 == nil { + w.Write([]byte{0x80}) + } else { + w.WriteUint64((*obj.Uint64)) + } + if obj.Uint64List == nil { + w.Write([]byte{0xC0}) + } else { + w.WriteUint64((*obj.Uint64List)) + } + if obj.String == nil { + w.Write([]byte{0x80}) + } else { + w.WriteString((*obj.String)) + } + if obj.StringList == nil { + w.Write([]byte{0xC0}) + } else { + w.WriteString((*obj.StringList)) + } + if obj.ByteArray == nil { + w.Write([]byte{0x80}) + } else { + w.WriteBytes(obj.ByteArray[:]) + } + if obj.ByteArrayList == nil { + w.Write([]byte{0xC0}) + } else { + w.WriteBytes(obj.ByteArrayList[:]) + } + if obj.ByteSlice == nil { + w.Write([]byte{0x80}) + } else { + w.WriteBytes((*obj.ByteSlice)) + } + if obj.ByteSliceList == nil { + w.Write([]byte{0xC0}) + } else { + w.WriteBytes((*obj.ByteSliceList)) + } + if obj.Struct == nil { + w.Write([]byte{0xC0}) + } else { + _tmp1 := w.List() + w.WriteUint64(uint64(obj.Struct.A)) + w.ListEnd(_tmp1) + } + if obj.StructString == nil { + w.Write([]byte{0x80}) + } else { + _tmp2 := w.List() + w.WriteUint64(uint64(obj.StructString.A)) + w.ListEnd(_tmp2) + } + w.ListEnd(_tmp0) + return w.Flush() +} + +func (obj *Test) DecodeRLP(dec *rlp.Stream) error { + var _tmp0 Test + { + if _, err := dec.List(); err != nil { + return err + } + // Uint8: + var _tmp2 *byte + if _tmp3, _tmp4, err := dec.Kind(); err != nil { + return err + } else if _tmp4 != 0 || _tmp3 != rlp.String { + _tmp1, err := dec.Uint8() + if err != nil { + return err + } + _tmp2 = &_tmp1 + } + _tmp0.Uint8 = _tmp2 + // Uint8List: + var _tmp6 *byte + if _tmp7, _tmp8, err := dec.Kind(); err != nil { + return err + } else if _tmp8 != 0 || _tmp7 != rlp.List { + _tmp5, err := dec.Uint8() + if err != nil { + return err + } + _tmp6 = &_tmp5 + } + _tmp0.Uint8List = _tmp6 + // Uint32: + var _tmp10 *uint32 + if _tmp11, _tmp12, err := dec.Kind(); err != nil { + return err + } else if _tmp12 != 0 || _tmp11 != rlp.String { + _tmp9, err := dec.Uint32() + if err != nil { + return err + } + _tmp10 = &_tmp9 + } + _tmp0.Uint32 = _tmp10 + // Uint32List: + var _tmp14 *uint32 + if _tmp15, _tmp16, err := dec.Kind(); err != nil { + return err + } else if _tmp16 != 0 || _tmp15 != rlp.List { + _tmp13, err := dec.Uint32() + if err != nil { + return err + } + _tmp14 = &_tmp13 + } + _tmp0.Uint32List = _tmp14 + // Uint64: + var _tmp18 *uint64 + if _tmp19, _tmp20, err := dec.Kind(); err != nil { + return err + } else if _tmp20 != 0 || _tmp19 != rlp.String { + _tmp17, err := dec.Uint64() + if err != nil { + return err + } + _tmp18 = &_tmp17 + } + _tmp0.Uint64 = _tmp18 + // Uint64List: + var _tmp22 *uint64 + if _tmp23, _tmp24, err := dec.Kind(); err != nil { + return err + } else if _tmp24 != 0 || _tmp23 != rlp.List { + _tmp21, err := dec.Uint64() + if err != nil { + return err + } + _tmp22 = &_tmp21 + } + _tmp0.Uint64List = _tmp22 + // String: + var _tmp26 *string + if _tmp27, _tmp28, err := dec.Kind(); err != nil { + return err + } else if _tmp28 != 0 || _tmp27 != rlp.String { + _tmp25, err := dec.String() + if err != nil { + return err + } + _tmp26 = &_tmp25 + } + _tmp0.String = _tmp26 + // StringList: + var _tmp30 *string + if _tmp31, _tmp32, err := dec.Kind(); err != nil { + return err + } else if _tmp32 != 0 || _tmp31 != rlp.List { + _tmp29, err := dec.String() + if err != nil { + return err + } + _tmp30 = &_tmp29 + } + _tmp0.StringList = _tmp30 + // ByteArray: + var _tmp34 *[3]byte + if _tmp35, _tmp36, err := dec.Kind(); err != nil { + return err + } else if _tmp36 != 0 || _tmp35 != rlp.String { + var _tmp33 [3]byte + if err := dec.ReadBytes(_tmp33[:]); err != nil { + return err + } + _tmp34 = &_tmp33 + } + _tmp0.ByteArray = _tmp34 + // ByteArrayList: + var _tmp38 *[3]byte + if _tmp39, _tmp40, err := dec.Kind(); err != nil { + return err + } else if _tmp40 != 0 || _tmp39 != rlp.List { + var _tmp37 [3]byte + if err := dec.ReadBytes(_tmp37[:]); err != nil { + return err + } + _tmp38 = &_tmp37 + } + _tmp0.ByteArrayList = _tmp38 + // ByteSlice: + var _tmp42 *[]byte + if _tmp43, _tmp44, err := dec.Kind(); err != nil { + return err + } else if _tmp44 != 0 || _tmp43 != rlp.String { + _tmp41, err := dec.Bytes() + if err != nil { + return err + } + _tmp42 = &_tmp41 + } + _tmp0.ByteSlice = _tmp42 + // ByteSliceList: + var _tmp46 *[]byte + if _tmp47, _tmp48, err := dec.Kind(); err != nil { + return err + } else if _tmp48 != 0 || _tmp47 != rlp.List { + _tmp45, err := dec.Bytes() + if err != nil { + return err + } + _tmp46 = &_tmp45 + } + _tmp0.ByteSliceList = _tmp46 + // Struct: + var _tmp51 *Aux + if _tmp52, _tmp53, err := dec.Kind(); err != nil { + return err + } else if _tmp53 != 0 || _tmp52 != rlp.List { + var _tmp49 Aux + { + if _, err := dec.List(); err != nil { + return err + } + // A: + _tmp50, err := dec.Uint32() + if err != nil { + return err + } + _tmp49.A = _tmp50 + if err := dec.ListEnd(); err != nil { + return err + } + } + _tmp51 = &_tmp49 + } + _tmp0.Struct = _tmp51 + // StructString: + var _tmp56 *Aux + if _tmp57, _tmp58, err := dec.Kind(); err != nil { + return err + } else if _tmp58 != 0 || _tmp57 != rlp.String { + var _tmp54 Aux + { + if _, err := dec.List(); err != nil { + return err + } + // A: + _tmp55, err := dec.Uint32() + if err != nil { + return err + } + _tmp54.A = _tmp55 + if err := dec.ListEnd(); err != nil { + return err + } + } + _tmp56 = &_tmp54 + } + _tmp0.StructString = _tmp56 + if err := dec.ListEnd(); err != nil { + return err + } + } + *obj = _tmp0 + return nil +} diff --git a/rlp/rlpgen/testdata/optional.in.txt b/rlp/rlpgen/testdata/optional.in.txt new file mode 100644 index 000000000..f1ac9f789 --- /dev/null +++ b/rlp/rlpgen/testdata/optional.in.txt @@ -0,0 +1,17 @@ +// -*- mode: go -*- + +package test + +type Aux struct { + A uint64 +} + +type Test struct { + Uint64 uint64 `rlp:"optional"` + Pointer *uint64 `rlp:"optional"` + String string `rlp:"optional"` + Slice []uint64 `rlp:"optional"` + Array [3]byte `rlp:"optional"` + NamedStruct Aux `rlp:"optional"` + AnonStruct struct{ A string } `rlp:"optional"` +} diff --git a/rlp/rlpgen/testdata/optional.out.txt b/rlp/rlpgen/testdata/optional.out.txt new file mode 100644 index 000000000..02df8e457 --- /dev/null +++ b/rlp/rlpgen/testdata/optional.out.txt @@ -0,0 +1,153 @@ +package test + +import "github.com/ethereum/go-ethereum/rlp" +import "io" + +func (obj *Test) EncodeRLP(_w io.Writer) error { + w := rlp.NewEncoderBuffer(_w) + _tmp0 := w.List() + _tmp1 := obj.Uint64 != 0 + _tmp2 := obj.Pointer != nil + _tmp3 := obj.String != "" + _tmp4 := len(obj.Slice) > 0 + _tmp5 := obj.Array != ([3]byte{}) + _tmp6 := obj.NamedStruct != (Aux{}) + _tmp7 := obj.AnonStruct != (struct{ A string }{}) + if _tmp1 || _tmp2 || _tmp3 || _tmp4 || _tmp5 || _tmp6 || _tmp7 { + w.WriteUint64(obj.Uint64) + } + if _tmp2 || _tmp3 || _tmp4 || _tmp5 || _tmp6 || _tmp7 { + if obj.Pointer == nil { + w.Write([]byte{0x80}) + } else { + w.WriteUint64((*obj.Pointer)) + } + } + if _tmp3 || _tmp4 || _tmp5 || _tmp6 || _tmp7 { + w.WriteString(obj.String) + } + if _tmp4 || _tmp5 || _tmp6 || _tmp7 { + _tmp8 := w.List() + for _, _tmp9 := range obj.Slice { + w.WriteUint64(_tmp9) + } + w.ListEnd(_tmp8) + } + if _tmp5 || _tmp6 || _tmp7 { + w.WriteBytes(obj.Array[:]) + } + if _tmp6 || _tmp7 { + _tmp10 := w.List() + w.WriteUint64(obj.NamedStruct.A) + w.ListEnd(_tmp10) + } + if _tmp7 { + _tmp11 := w.List() + w.WriteString(obj.AnonStruct.A) + w.ListEnd(_tmp11) + } + w.ListEnd(_tmp0) + return w.Flush() +} + +func (obj *Test) DecodeRLP(dec *rlp.Stream) error { + var _tmp0 Test + { + if _, err := dec.List(); err != nil { + return err + } + // Uint64: + if dec.MoreDataInList() { + _tmp1, err := dec.Uint64() + if err != nil { + return err + } + _tmp0.Uint64 = _tmp1 + // Pointer: + if dec.MoreDataInList() { + _tmp2, err := dec.Uint64() + if err != nil { + return err + } + _tmp0.Pointer = &_tmp2 + // String: + if dec.MoreDataInList() { + _tmp3, err := dec.String() + if err != nil { + return err + } + _tmp0.String = _tmp3 + // Slice: + if dec.MoreDataInList() { + var _tmp4 []uint64 + if _, err := dec.List(); err != nil { + return err + } + for dec.MoreDataInList() { + _tmp5, err := dec.Uint64() + if err != nil { + return err + } + _tmp4 = append(_tmp4, _tmp5) + } + if err := dec.ListEnd(); err != nil { + return err + } + _tmp0.Slice = _tmp4 + // Array: + if dec.MoreDataInList() { + var _tmp6 [3]byte + if err := dec.ReadBytes(_tmp6[:]); err != nil { + return err + } + _tmp0.Array = _tmp6 + // NamedStruct: + if dec.MoreDataInList() { + var _tmp7 Aux + { + if _, err := dec.List(); err != nil { + return err + } + // A: + _tmp8, err := dec.Uint64() + if err != nil { + return err + } + _tmp7.A = _tmp8 + if err := dec.ListEnd(); err != nil { + return err + } + } + _tmp0.NamedStruct = _tmp7 + // AnonStruct: + if dec.MoreDataInList() { + var _tmp9 struct{ A string } + { + if _, err := dec.List(); err != nil { + return err + } + // A: + _tmp10, err := dec.String() + if err != nil { + return err + } + _tmp9.A = _tmp10 + if err := dec.ListEnd(); err != nil { + return err + } + } + _tmp0.AnonStruct = _tmp9 + } + } + } + } + } + } + } + if err := dec.ListEnd(); err != nil { + return err + } + } + *obj = _tmp0 + return nil +} diff --git a/rlp/rlpgen/testdata/rawvalue.in.txt b/rlp/rlpgen/testdata/rawvalue.in.txt new file mode 100644 index 000000000..3a657bc90 --- /dev/null +++ b/rlp/rlpgen/testdata/rawvalue.in.txt @@ -0,0 +1,11 @@ +// -*- mode: go -*- + +package test + +import "github.com/ethereum/go-ethereum/rlp" + +type Test struct { + RawValue rlp.RawValue + PointerToRawValue *rlp.RawValue + SliceOfRawValue []rlp.RawValue +} diff --git a/rlp/rlpgen/testdata/rawvalue.out.txt b/rlp/rlpgen/testdata/rawvalue.out.txt new file mode 100644 index 000000000..3607c9863 --- /dev/null +++ b/rlp/rlpgen/testdata/rawvalue.out.txt @@ -0,0 +1,64 @@ +package test + +import "github.com/ethereum/go-ethereum/rlp" +import "io" + +func (obj *Test) EncodeRLP(_w io.Writer) error { + w := rlp.NewEncoderBuffer(_w) + _tmp0 := w.List() + w.Write(obj.RawValue) + if obj.PointerToRawValue == nil { + w.Write([]byte{0x80}) + } else { + w.Write((*obj.PointerToRawValue)) + } + _tmp1 := w.List() + for _, _tmp2 := range obj.SliceOfRawValue { + w.Write(_tmp2) + } + w.ListEnd(_tmp1) + w.ListEnd(_tmp0) + return w.Flush() +} + +func (obj *Test) DecodeRLP(dec *rlp.Stream) error { + var _tmp0 Test + { + if _, err := dec.List(); err != nil { + return err + } + // RawValue: + _tmp1, err := dec.Raw() + if err != nil { + return err + } + _tmp0.RawValue = _tmp1 + // PointerToRawValue: + _tmp2, err := dec.Raw() + if err != nil { + return err + } + _tmp0.PointerToRawValue = &_tmp2 + // SliceOfRawValue: + var _tmp3 []rlp.RawValue + if _, err := dec.List(); err != nil { + return err + } + for dec.MoreDataInList() { + _tmp4, err := dec.Raw() + if err != nil { + return err + } + _tmp3 = append(_tmp3, _tmp4) + } + if err := dec.ListEnd(); err != nil { + return err + } + _tmp0.SliceOfRawValue = _tmp3 + if err := dec.ListEnd(); err != nil { + return err + } + } + *obj = _tmp0 + return nil +} diff --git a/rlp/rlpgen/testdata/uints.in.txt b/rlp/rlpgen/testdata/uints.in.txt new file mode 100644 index 000000000..8095da997 --- /dev/null +++ b/rlp/rlpgen/testdata/uints.in.txt @@ -0,0 +1,10 @@ +// -*- mode: go -*- + +package test + +type Test struct{ + A uint8 + B uint16 + C uint32 + D uint64 +} diff --git a/rlp/rlpgen/testdata/uints.out.txt b/rlp/rlpgen/testdata/uints.out.txt new file mode 100644 index 000000000..1a354956a --- /dev/null +++ b/rlp/rlpgen/testdata/uints.out.txt @@ -0,0 +1,53 @@ +package test + +import "github.com/ethereum/go-ethereum/rlp" +import "io" + +func (obj *Test) EncodeRLP(_w io.Writer) error { + w := rlp.NewEncoderBuffer(_w) + _tmp0 := w.List() + w.WriteUint64(uint64(obj.A)) + w.WriteUint64(uint64(obj.B)) + w.WriteUint64(uint64(obj.C)) + w.WriteUint64(obj.D) + w.ListEnd(_tmp0) + return w.Flush() +} + +func (obj *Test) DecodeRLP(dec *rlp.Stream) error { + var _tmp0 Test + { + if _, err := dec.List(); err != nil { + return err + } + // A: + _tmp1, err := dec.Uint8() + if err != nil { + return err + } + _tmp0.A = _tmp1 + // B: + _tmp2, err := dec.Uint16() + if err != nil { + return err + } + _tmp0.B = _tmp2 + // C: + _tmp3, err := dec.Uint32() + if err != nil { + return err + } + _tmp0.C = _tmp3 + // D: + _tmp4, err := dec.Uint64() + if err != nil { + return err + } + _tmp0.D = _tmp4 + if err := dec.ListEnd(); err != nil { + return err + } + } + *obj = _tmp0 + return nil +} diff --git a/rlp/rlpgen/types.go b/rlp/rlpgen/types.go new file mode 100644 index 000000000..5926a801e --- /dev/null +++ b/rlp/rlpgen/types.go @@ -0,0 +1,98 @@ +package main + +import ( + "fmt" + "go/types" + "reflect" +) + +// typeReflectKind gives the reflect.Kind that represents typ. +func typeReflectKind(typ types.Type) reflect.Kind { + switch typ := typ.(type) { + case *types.Basic: + k := typ.Kind() + if k >= types.Bool && k <= types.Complex128 { + // value order matches for Bool..Complex128 + return reflect.Bool + reflect.Kind(k-types.Bool) + } + if k == types.String { + return reflect.String + } + if k == types.UnsafePointer { + return reflect.UnsafePointer + } + panic(fmt.Errorf("unhandled BasicKind %v", k)) + case *types.Array: + return reflect.Array + case *types.Chan: + return reflect.Chan + case *types.Interface: + return reflect.Interface + case *types.Map: + return reflect.Map + case *types.Pointer: + return reflect.Ptr + case *types.Signature: + return reflect.Func + case *types.Slice: + return reflect.Slice + case *types.Struct: + return reflect.Struct + default: + panic(fmt.Errorf("unhandled type %T", typ)) + } +} + +// nonZeroCheck returns the expression that checks whether 'v' is a non-zero value of type 'vtyp'. +func nonZeroCheck(v string, vtyp types.Type, qualify types.Qualifier) string { + // Resolve type name. + typ := resolveUnderlying(vtyp) + switch typ := typ.(type) { + case *types.Basic: + k := typ.Kind() + switch { + case k == types.Bool: + return v + case k >= types.Uint && k <= types.Complex128: + return fmt.Sprintf("%s != 0", v) + case k == types.String: + return fmt.Sprintf(`%s != ""`, v) + default: + panic(fmt.Errorf("unhandled BasicKind %v", k)) + } + case *types.Array, *types.Struct: + return fmt.Sprintf("%s != (%s{})", v, types.TypeString(vtyp, qualify)) + case *types.Interface, *types.Pointer, *types.Signature: + return fmt.Sprintf("%s != nil", v) + case *types.Slice, *types.Map: + return fmt.Sprintf("len(%s) > 0", v) + default: + panic(fmt.Errorf("unhandled type %T", typ)) + } +} + +// isBigInt checks whether 'typ' is "math/big".Int. +func isBigInt(typ types.Type) bool { + named, ok := typ.(*types.Named) + if !ok { + return false + } + name := named.Obj() + return name.Pkg().Path() == "math/big" && name.Name() == "Int" +} + +// isByte checks whether the underlying type of 'typ' is uint8. +func isByte(typ types.Type) bool { + basic, ok := resolveUnderlying(typ).(*types.Basic) + return ok && basic.Kind() == types.Uint8 +} + +func resolveUnderlying(typ types.Type) types.Type { + for { + t := typ.Underlying() + if t == typ { + return t + } + typ = t + } +} diff --git a/rlp/typecache.go b/rlp/typecache.go index 62553d3b5..3e37c9d2f 100644 --- a/rlp/typecache.go +++ b/rlp/typecache.go @@ -19,9 +19,10 @@ package rlp import ( "fmt" "reflect" - "strings" "sync" "sync/atomic" + + "github.com/ethereum/go-ethereum/rlp/internal/rlpstruct" ) // typeinfo is an entry in the type cache. @@ -32,35 +33,16 @@ type typeinfo struct { writerErr error // error from makeWriter } -// tags represents struct tags. -type tags struct { - // rlp:"nil" controls whether empty input results in a nil pointer. - // nilKind is the kind of empty value allowed for the field. - nilKind Kind - nilOK bool - - // rlp:"optional" allows for a field to be missing in the input list. - // If this is set, all subsequent fields must also be optional. - optional bool - - // rlp:"tail" controls whether this field swallows additional list elements. It can - // only be set for the last field, which must be of slice type. - tail bool - - // rlp:"-" ignores fields. - ignored bool -} - // typekey is the key of a type in typeCache. It includes the struct tags because // they might generate a different decoder. type typekey struct { reflect.Type - tags + rlpstruct.Tags } type decoder func(*Stream, reflect.Value) error -type writer func(reflect.Value, *encbuf) error +type writer func(reflect.Value, *encBuffer) error var theTC = newTypeCache() @@ -95,10 +77,10 @@ func (c *typeCache) info(typ reflect.Type) *typeinfo { } // Not in the cache, need to generate info for this type. - return c.generate(typ, tags{}) + return c.generate(typ, rlpstruct.Tags{}) } -func (c *typeCache) generate(typ reflect.Type, tags tags) *typeinfo { +func (c *typeCache) generate(typ reflect.Type, tags rlpstruct.Tags) *typeinfo { c.mu.Lock() defer c.mu.Unlock() @@ -122,7 +104,7 @@ func (c *typeCache) generate(typ reflect.Type, tags tags) *typeinfo { return info } -func (c *typeCache) infoWhileGenerating(typ reflect.Type, tags tags) *typeinfo { +func (c *typeCache) infoWhileGenerating(typ reflect.Type, tags rlpstruct.Tags) *typeinfo { key := typekey{typ, tags} if info := c.next[key]; info != nil { return info @@ -144,35 +126,40 @@ type field struct { // structFields resolves the typeinfo of all public fields in a struct type. func structFields(typ reflect.Type) (fields []field, err error) { - var ( - lastPublic = lastPublicField(typ) - anyOptional = false - ) + // Convert fields to rlpstruct.Field. + var allStructFields []rlpstruct.Field for i := 0; i < typ.NumField(); i++ { - if f := typ.Field(i); f.PkgPath == "" { // exported - tags, err := parseStructTag(typ, i, lastPublic) - if err != nil { - return nil, err - } + rf := typ.Field(i) + allStructFields = append(allStructFields, rlpstruct.Field{ + Name: rf.Name, + Index: i, + Exported: rf.PkgPath == "", + Tag: string(rf.Tag), + Type: *rtypeToStructType(rf.Type, nil), + }) + } - // Skip rlp:"-" fields. - if tags.ignored { - continue - } - // If any field has the "optional" tag, subsequent fields must also have it. - if tags.optional || tags.tail { - anyOptional = true - } else if anyOptional { - return nil, fmt.Errorf(`rlp: struct field %v.%s needs "optional" tag`, typ, f.Name) - } - info := theTC.infoWhileGenerating(f.Type, tags) - fields = append(fields, field{i, info, tags.optional}) + // Filter/validate fields. + structFields, structTags, err := rlpstruct.ProcessFields(allStructFields) + if err != nil { + if tagErr, ok := err.(rlpstruct.TagError); ok { + tagErr.StructType = typ.String() + return nil, tagErr } + return nil, err + } + + // Resolve typeinfo. + for i, sf := range structFields { + typ := typ.Field(sf.Index).Type + tags := structTags[i] + info := theTC.infoWhileGenerating(typ, tags) + fields = append(fields, field{sf.Index, info, tags.Optional}) } return fields, nil } -// anyOptionalFields returns the index of the first field with "optional" tag. +// firstOptionalField returns the index of the first field with "optional" tag. func firstOptionalField(fields []field) int { for i, f := range fields { if f.optional { @@ -192,82 +179,56 @@ func (e structFieldError) Error() string { return fmt.Sprintf("%v (struct field %v.%s)", e.err, e.typ, e.typ.Field(e.field).Name) } -type structTagError struct { - typ reflect.Type - field, tag, err string -} - -func (e structTagError) Error() string { - return fmt.Sprintf("rlp: invalid struct tag %q for %v.%s (%s)", e.tag, e.typ, e.field, e.err) -} - -func parseStructTag(typ reflect.Type, fi, lastPublic int) (tags, error) { - f := typ.Field(fi) - var ts tags - for _, t := range strings.Split(f.Tag.Get("rlp"), ",") { - switch t = strings.TrimSpace(t); t { - case "": - case "-": - ts.ignored = true - case "nil", "nilString", "nilList": - ts.nilOK = true - if f.Type.Kind() != reflect.Ptr { - return ts, structTagError{typ, f.Name, t, "field is not a pointer"} - } - switch t { - case "nil": - ts.nilKind = defaultNilKind(f.Type.Elem()) - case "nilString": - ts.nilKind = String - case "nilList": - ts.nilKind = List - } - case "optional": - ts.optional = true - if ts.tail { - return ts, structTagError{typ, f.Name, t, `also has "tail" tag`} - } - case "tail": - ts.tail = true - if fi != lastPublic { - return ts, structTagError{typ, f.Name, t, "must be on last field"} - } - if ts.optional { - return ts, structTagError{typ, f.Name, t, `also has "optional" tag`} - } - if f.Type.Kind() != reflect.Slice { - return ts, structTagError{typ, f.Name, t, "field type is not slice"} - } - default: - return ts, fmt.Errorf("rlp: unknown struct tag %q on %v.%s", t, typ, f.Name) - } - } - return ts, nil -} - -func lastPublicField(typ reflect.Type) int { - last := 0 - for i := 0; i < typ.NumField(); i++ { - if typ.Field(i).PkgPath == "" { - last = i - } - } - return last -} - -func (i *typeinfo) generate(typ reflect.Type, tags tags) { +func (i *typeinfo) generate(typ reflect.Type, tags rlpstruct.Tags) { i.decoder, i.decoderErr = makeDecoder(typ, tags) i.writer, i.writerErr = makeWriter(typ, tags) } -// defaultNilKind determines whether a nil pointer to typ encodes/decodes -// as an empty string or empty list. -func defaultNilKind(typ reflect.Type) Kind { +// rtypeToStructType converts typ to rlpstruct.Type. +func rtypeToStructType(typ reflect.Type, rec map[reflect.Type]*rlpstruct.Type) *rlpstruct.Type { k := typ.Kind() - if isUint(k) || k == reflect.String || k == reflect.Bool || isByteArray(typ) { - return String + if k == reflect.Invalid { + panic("invalid kind") + } + + if prev := rec[typ]; prev != nil { + return prev // short-circuit for recursive types + } + if rec == nil { + rec = make(map[reflect.Type]*rlpstruct.Type) + } + + t := &rlpstruct.Type{ + Name: typ.String(), + Kind: k, + IsEncoder: typ.Implements(encoderInterface), + IsDecoder: typ.Implements(decoderInterface), + } + rec[typ] = t + if k == reflect.Array || k == reflect.Slice || k == reflect.Ptr { + t.Elem = rtypeToStructType(typ.Elem(), rec) + } + return t +} + +// typeNilKind gives the RLP value kind for nil pointers to 'typ'. +func typeNilKind(typ reflect.Type, tags rlpstruct.Tags) Kind { + styp := rtypeToStructType(typ, nil) + + var nk rlpstruct.NilKind + if tags.NilOK { + nk = tags.NilKind + } else { + nk = styp.DefaultNilValue() + } + switch nk { + case rlpstruct.NilKindString: + return String + case rlpstruct.NilKindList: + return List + default: + panic("invalid nil kind value") } - return List } func isUint(k reflect.Kind) bool { @@ -277,7 +238,3 @@ func isUint(k reflect.Kind) bool { func isByte(typ reflect.Type) bool { return typ.Kind() == reflect.Uint8 && !typ.Implements(encoderInterface) } - -func isByteArray(typ reflect.Type) bool { - return (typ.Kind() == reflect.Slice || typ.Kind() == reflect.Array) && isByte(typ.Elem()) -}