lbcwallet/tx/tx.go
2013-08-27 12:39:45 -04:00

435 lines
10 KiB
Go

/*
* Copyright (c) 2013 Conformal Systems LLC <info@conformal.com>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
package tx
import (
"bytes"
"code.google.com/p/go.crypto/ripemd160"
"encoding/binary"
"fmt"
"github.com/conformal/btcwire"
"io"
)
// Byte headers prepending confirmed and unconfirmed serialized UTXOs.
const (
ConfirmedUtxoHeader byte = iota
UnconfirmedUtxoHeader
)
// Byte headers prepending received and sent serialized transactions.
const (
RecvTxHeader byte = iota
SendTxHeader
)
type UtxoStore struct {
Confirmed []*Utxo
Unconfirmed []*Utxo
}
type Utxo struct {
TxHash btcwire.ShaHash
Amt int64 // Measured in Satoshis
Height int64
}
// TxStore is a slice holding RecvTx and SendTx pointers.
type TxStore []interface{}
type RecvTx struct {
TxHash btcwire.ShaHash
Amt int64 // Measured in Satoshis
SenderAddr [ripemd160.Size]byte
ReceiverAddr [ripemd160.Size]byte
}
type SendTx struct {
TxHash btcwire.ShaHash
Fee int64 // Measured in Satoshis
SenderAddr [ripemd160.Size]byte
ReceiverAddrs []struct {
Addr [ripemd160.Size]byte
Amt int64 // Measured in Satoshis
}
}
// We want to use binaryRead and binaryWrite instead of binary.Read
// and binary.Write because those from the binary package do not return
// the number of bytes actually written or read. We need to return
// this value to correctly support the io.ReaderFrom and io.WriterTo
// interfaces.
func binaryRead(r io.Reader, order binary.ByteOrder, data interface{}) (n int64, err error) {
var read int
buf := make([]byte, binary.Size(data))
if read, err = r.Read(buf); err != nil {
return int64(read), err
}
return int64(read), binary.Read(bytes.NewBuffer(buf), order, data)
}
// See comment for binaryRead().
func binaryWrite(w io.Writer, order binary.ByteOrder, data interface{}) (n int64, err error) {
var buf bytes.Buffer
if err = binary.Write(&buf, order, data); err != nil {
return 0, err
}
written, err := w.Write(buf.Bytes())
return int64(written), err
}
// ReadFrom satisifies the io.ReaderFrom interface. Utxo structs are
// read in from r until an io.EOF is reached. If an io.EOF is reached
// before a Utxo is finished being read, err will be non-nil.
func (u *UtxoStore) ReadFrom(r io.Reader) (n int64, err error) {
var read int64
for {
// Read header
var header byte
read, err = binaryRead(r, binary.LittleEndian, &header)
if err != nil {
// EOF here is not an error.
if err == io.EOF {
return n + read, nil
}
return n + read, err
}
n += read
// Read Utxo
var slicep *[]*Utxo
switch header {
case ConfirmedUtxoHeader:
slicep = &u.Confirmed
case UnconfirmedUtxoHeader:
slicep = &u.Unconfirmed
default:
return n, fmt.Errorf("Unknown Utxo header.")
}
utxo := new(Utxo)
read, err = utxo.ReadFrom(r)
if err != nil {
return n + read, err
}
n += read
*slicep = append(*slicep, utxo)
}
}
// WriteTo satisifies the io.WriterTo interface. Each Utxo is written
// to w, prepended by a single byte header to distinguish between
// confirmed and unconfirmed outputs.
func (u *UtxoStore) WriteTo(w io.Writer) (n int64, err error) {
var written int64
for _, utxo := range u.Confirmed {
// Write header
written, err = binaryWrite(w, binary.LittleEndian, ConfirmedUtxoHeader)
if err != nil {
return n + written, err
}
n += written
// Write Utxo
written, err = utxo.WriteTo(w)
if err != nil {
return n + written, err
}
n += written
}
for _, utxo := range u.Unconfirmed {
// Write header
written, err = binaryWrite(w, binary.LittleEndian, UnconfirmedUtxoHeader)
if err != nil {
return n + written, err
}
n += written
// Write Utxo
written, err = utxo.WriteTo(w)
if err != nil {
return n + written, err
}
n += written
}
return n, nil
}
// ReadFrom satisifies the io.ReaderFrom interface. A Utxo is read
// from r with the format:
//
// [TxHash (32 bytes), Amt (8 bytes), Height (8 bytes)]
//
// Each field is read little endian.
func (u *Utxo) ReadFrom(r io.Reader) (n int64, err error) {
datas := []interface{}{
&u.TxHash,
&u.Amt,
&u.Height,
}
var read int64
for _, data := range datas {
read, err = binaryRead(r, binary.LittleEndian, data)
if err != nil {
return n + read, err
}
n += read
}
return n, nil
}
// WriteTo satisifies the io.WriterTo interface. A Utxo is written to
// w in the format:
//
// [TxHash (32 bytes), Amt (8 bytes), Height (8 bytes)]
//
// Each field is written little endian.
func (u *Utxo) WriteTo(w io.Writer) (n int64, err error) {
datas := []interface{}{
&u.TxHash,
&u.Amt,
&u.Height,
}
var written int64
for _, data := range datas {
written, err = binaryWrite(w, binary.LittleEndian, data)
if err != nil {
return n + written, err
}
n += written
}
return n, nil
}
// ReadFrom satisifies the io.ReaderFrom interface. A TxStore is read
// in from r with the format:
//
// [[TxHeader (1 byte), Tx (varies in size)]...]
func (txs *TxStore) ReadFrom(r io.Reader) (n int64, err error) {
store := []interface{}{}
defer func() {
*txs = store
}()
var read int64
for {
// Read header
var header byte
read, err = binaryRead(r, binary.LittleEndian, &header)
if err != nil {
// io.EOF is not an error here.
if err == io.EOF {
return n + read, nil
}
return n + read, err
}
n += read
var tx io.ReaderFrom
switch header {
case RecvTxHeader:
tx = new(RecvTx)
case SendTxHeader:
tx = new(SendTx)
default:
return n, fmt.Errorf("Unknown Tx header")
}
// Read tx
read, err = tx.ReadFrom(r)
if err != nil {
return n + read, err
}
n += read
store = append(store, tx)
}
}
// WriteTo satisifies the io.WriterTo interface. A TxStore is written
// to w in the format:
//
// [[TxHeader (1 byte), Tx (varies in size)]...]
func (txs *TxStore) WriteTo(w io.Writer) (n int64, err error) {
store := ([]interface{})(*txs)
var written int64
for _, tx := range store {
switch tx.(type) {
case *RecvTx:
written, err = binaryWrite(w, binary.LittleEndian, RecvTxHeader)
if err != nil {
return n + written, err
}
n += written
case *SendTx:
written, err = binaryWrite(w, binary.LittleEndian, SendTxHeader)
if err != nil {
return n + written, err
}
n += written
default:
return n, fmt.Errorf("Unknown type in TxStore")
}
wt := tx.(io.WriterTo)
written, err = wt.WriteTo(w)
if err != nil {
return n + written, err
}
n += written
}
return n, nil
}
// ReadFrom satisifies the io.ReaderFrom interface. A RecTx is read
// in from r with the format:
//
// [TxHash (32 bytes), Amt (8 bytes), SenderAddr (20 bytes), ReceiverAddr (20 bytes)]
//
// Each field is read little endian.
func (tx *RecvTx) ReadFrom(r io.Reader) (n int64, err error) {
datas := []interface{}{
&tx.TxHash,
&tx.Amt,
&tx.SenderAddr,
&tx.ReceiverAddr,
}
var read int64
for _, data := range datas {
read, err = binaryRead(r, binary.LittleEndian, data)
if err != nil {
return n + read, err
}
n += read
}
return n, nil
}
// WriteTo satisifies the io.WriterTo interface. A RecvTx is written to
// w in the format:
//
// [TxHash (32 bytes), Amt (8 bytes), SenderAddr (20 bytes), ReceiverAddr (20 bytes)]
//
// Each field is written little endian.
func (tx *RecvTx) WriteTo(w io.Writer) (n int64, err error) {
datas := []interface{}{
&tx.TxHash,
&tx.Amt,
&tx.SenderAddr,
&tx.ReceiverAddr,
}
var written int64
for _, data := range datas {
written, err = binaryWrite(w, binary.LittleEndian, data)
if err != nil {
return n + written, err
}
n += written
}
return n, nil
}
// ReadFrom satisifies the io.WriterTo interface. A SendTx is read
// from r with the format:
//
// [TxHash (32 bytes), Fee (8 bytes), SenderAddr (20 bytes), len(ReceiverAddrs) (4 bytes), ReceiverAddrs[Addr (20 bytes), Amt (8 bytes)]...]
//
// Each field is read little endian.
func (tx *SendTx) ReadFrom(r io.Reader) (n int64, err error) {
var nReceivers uint32
datas := []interface{}{
&tx.TxHash,
&tx.Fee,
&tx.SenderAddr,
&nReceivers,
}
var read int64
for _, data := range datas {
read, err = binaryRead(r, binary.LittleEndian, data)
if err != nil {
return n + read, err
}
n += read
}
if nReceivers == 0 {
// XXX: Is this valid? Entire output is a fee for the miner?
return n, nil
}
tx.ReceiverAddrs = make([]struct {
Addr [ripemd160.Size]byte
Amt int64
},
nReceivers)
for i := uint32(0); i < nReceivers; i++ {
datas := []interface{}{
&tx.ReceiverAddrs[i].Addr,
&tx.ReceiverAddrs[i].Amt,
}
for _, data := range datas {
read, err = binaryRead(r, binary.LittleEndian, data)
if err != nil {
return n + read, err
}
n += read
}
}
return n, nil
}
// WriteTo satisifies the io.WriterTo interface. A RecvTx is written to
// w in the format:
//
// [TxHash (32 bytes), Fee (8 bytes), SenderAddr (20 bytes), len(ReceiverAddrs) (4 bytes), ReceiverAddrs[Addr (20 bytes), Amt (8 bytes)]...]
//
// Each field is written little endian.
func (tx *SendTx) WriteTo(w io.Writer) (n int64, err error) {
nReceivers := uint32(len(tx.ReceiverAddrs))
if int64(nReceivers) != int64(len(tx.ReceiverAddrs)) {
return n, fmt.Errorf("Too many receiving addresses.")
}
datas := []interface{}{
&tx.TxHash,
&tx.Fee,
&tx.SenderAddr,
nReceivers,
}
var written int64
for _, data := range datas {
written, err = binaryWrite(w, binary.LittleEndian, data)
if err != nil {
return n + written, err
}
n += written
}
for i, _ := range tx.ReceiverAddrs {
datas := []interface{}{
&tx.ReceiverAddrs[i].Addr,
&tx.ReceiverAddrs[i].Amt,
}
for _, data := range datas {
written, err = binaryWrite(w, binary.LittleEndian, data)
if err != nil {
return n + written, err
}
n += written
}
}
return n, nil
}