diff options
Diffstat (limited to 'cli/vendor/github.com/ethereum/go-ethereum/rlp/encbuffer.go')
| -rw-r--r-- | cli/vendor/github.com/ethereum/go-ethereum/rlp/encbuffer.go | 398 |
1 files changed, 398 insertions, 0 deletions
diff --git a/cli/vendor/github.com/ethereum/go-ethereum/rlp/encbuffer.go b/cli/vendor/github.com/ethereum/go-ethereum/rlp/encbuffer.go new file mode 100644 index 0000000..687949c --- /dev/null +++ b/cli/vendor/github.com/ethereum/go-ethereum/rlp/encbuffer.go @@ -0,0 +1,398 @@ +// 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 <http://www.gnu.org/licenses/>. + +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 +} + +// makeBytes creates the encoder output. +func (w *encBuffer) makeBytes() []byte { + out := make([]byte, w.size()) + w.copyTo(out) + return out +} + +func (w *encBuffer) copyTo(dst []byte) { + strpos := 0 + pos := 0 + for _, head := range w.lheads { + // write string data before header + n := copy(dst[pos:], w.str[strpos:head.offset]) + pos += n + strpos += n + // write the header + enc := head.encode(dst[pos:]) + pos += len(enc) + } + // copy string data after the last list header + copy(dst[pos:], w.str[strpos:]) +} + +// writeTo writes the encoder output to w. +func (buf *encBuffer) writeTo(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...) + } +} + +func (buf *encBuffer) writeString(s string) { + buf.writeBytes([]byte(s)) +} + +// 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 + } +} + +func encBufferFromWriter(w io.Writer) *encBuffer { + switch w := w.(type) { + case EncoderBuffer: + return w.buf + case *EncoderBuffer: + return w.buf + case *encBuffer: + return w + 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 := encBufferFromWriter(dst); outer != nil { + *w = EncoderBuffer{outer, 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.writeTo(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.makeBytes() +} + +// AppendToBytes appends the encoded bytes to dst. +func (w *EncoderBuffer) AppendToBytes(dst []byte) []byte { + size := w.buf.size() + out := append(dst, make([]byte, size)...) + w.buf.copyTo(out[len(dst):]) + return out +} + +// 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) +} + +// WriteBytes encodes s as an RLP string. +func (w EncoderBuffer) WriteString(s string) { + w.buf.writeString(s) +} + +// 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) +} |
