Save the pkScript for each Utxo. This is needed to create transactions.

tx/tx.go

@@ -44,19 +44,22 @@ type UtxoStore struct {
 
 type Utxo struct {
 	Addr   [ripemd160.Size]byte
-	Out OutPoint
+	Out    OutPoint
-	Amt    int64 // Measured in Satoshis
+	Subscript PKScript
+	Amt    uint64 // Measured in Satoshis
 	Height int64
 }
 
 type OutPoint btcwire.OutPoint
 
+type PKScript []byte
+
 // TxStore is a slice holding RecvTx and SendTx pointers.
 type TxStore []interface{}
 
 type RecvTx struct {
 	TxHash       btcwire.ShaHash
-	Amt          int64 // Measured in Satoshis
+	Amt          uint64 // Measured in Satoshis
 	SenderAddr   [ripemd160.Size]byte
 	ReceiverAddr [ripemd160.Size]byte
 }
@@ -67,7 +70,7 @@ type SendTx struct {
 	SenderAddr    [ripemd160.Size]byte
 	ReceiverAddrs []struct {
 		Addr [ripemd160.Size]byte
-		Amt  int64 // Measured in Satoshis
+		Amt  uint64 // Measured in Satoshis
 	}
 }
 
@@ -178,13 +181,14 @@ func (u *UtxoStore) WriteTo(w io.Writer) (n int64, err error) {
 // ReadFrom satisifies the io.ReaderFrom interface.  A Utxo is read
 // from r with the format:
 //
-//  [Addr (20 bytes), Out (36 bytes), Amt (8 bytes), Height (8 bytes)]
+//  [Addr (20 bytes), Out (36 bytes), Subscript (varies), 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.Addr,
 		&u.Out,
+		&u.Subscript,
 		&u.Amt,
 		&u.Height,
 	}
@@ -206,13 +210,14 @@ func (u *Utxo) ReadFrom(r io.Reader) (n int64, err error) {
 // WriteTo satisifies the io.WriterTo interface.  A Utxo is written to
 // w in the format:
 //
-//  [Addr (20 bytes), Out (36 bytes), Amt (8 bytes), Height (8 bytes)]
+//  [Addr (20 bytes), Out (36 bytes), Subscript (varies), 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.Addr,
 		&u.Out,
+		&u.Subscript,
 		&u.Amt,
 		&u.Height,
 	}
@@ -231,7 +236,7 @@ func (u *Utxo) WriteTo(w io.Writer) (n int64, err error) {
 	return n, nil
 }
 
-// ReadFrom satisifies the io.ReaderFrom interface.  A OutPoint is read
+// ReadFrom satisifies the io.ReaderFrom interface.  An OutPoint is read
 // from r with the format:
 //
 //  [Hash (32 bytes), Index (4 bytes)]
@@ -253,7 +258,7 @@ func (o *OutPoint) ReadFrom(r io.Reader) (n int64, err error) {
 	return n, nil
 }
 
-// WriteTo satisifies the io.WriterTo interface.  A OutPoit is written
+// WriteTo satisifies the io.WriterTo interface.  An OutPoint is written
 // to w in the format:
 //
 //  [Hash (32 bytes), Index (4 bytes)]
@@ -275,6 +280,55 @@ func (o *OutPoint) WriteTo(w io.Writer) (n int64, err error) {
 	return n, nil
 }
 
+// ReadFrom satisifies the io.ReaderFrom interface.  A PKScript is read
+// from r with the format:
+//
+//  [Length (4 byte unsigned integer), ScriptBytes (Length bytes)]
+//
+// Length is read little endian.
+func (s *PKScript) ReadFrom(r io.Reader) (n int64, err error) {
+	var scriptlen uint32
+	var read int64
+	read, err = binaryRead(r, binary.LittleEndian, &scriptlen)
+	if err != nil {
+		return n + read, err
+	}
+	n += read
+
+	scriptbuf := new(bytes.Buffer)
+	read, err = scriptbuf.ReadFrom(io.LimitReader(r, int64(scriptlen)))
+	if err != nil {
+		return n + read, err
+	}
+	n += read
+	*s = scriptbuf.Bytes()
+
+	return n, nil
+}
+
+// WriteTo satisifies the io.WriterTo interface.  A PKScript is written
+// to w in the format:
+//
+//  [Length (4 byte unsigned integer), ScriptBytes (Length bytes)]
+//
+// Length is written little endian.
+func (s *PKScript) WriteTo(w io.Writer) (n int64, err error) {
+	var written int64
+	written, err = binaryWrite(w, binary.LittleEndian, uint32(len(*s)))
+	if err != nil {
+		return n + written, nil
+	}
+	n += written
+
+	written, err = bytes.NewBuffer(*s).WriteTo(w)
+	if err != nil {
+		return n + written, nil
+	}
+	n += written
+
+	return n, nil
+}
+
 // ReadFrom satisifies the io.ReaderFrom interface.  A TxStore is read
 // in from r with the format:
 //
@@ -430,7 +484,7 @@ func (tx *SendTx) ReadFrom(r io.Reader) (n int64, err error) {
 
 	tx.ReceiverAddrs = make([]struct {
 		Addr [ripemd160.Size]byte
-		Amt  int64
+		Amt  uint64
 	},
 		nReceivers)
 	for i := uint32(0); i < nReceivers; i++ {

tx/tx_test.go

@@ -28,8 +28,6 @@ import (
 )
 
 var (
-	utxoByteSize = binary.Size(Utxo{})
-
 	recvtx = &RecvTx{
 		TxHash: [btcwire.HashSize]byte{
 			0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
@@ -59,11 +57,11 @@ var (
 		},
 		ReceiverAddrs: []struct {
 			Addr [ripemd160.Size]byte
-			Amt  int64
+			Amt  uint64
 		}{
 			struct {
 				Addr [ripemd160.Size]byte
-				Amt  int64
+				Amt  uint64
 			}{
 				Amt: 69,
 				Addr: [ripemd160.Size]byte{
@@ -73,7 +71,7 @@ var (
 			},
 			struct {
 				Addr [ripemd160.Size]byte
-				Amt  int64
+				Amt  uint64
 			}{
 				Amt: 96,
 				Addr: [ripemd160.Size]byte{
@@ -99,26 +97,24 @@ func TestUtxoWriteRead(t *testing.T) {
 			},
 			Index: 1,
 		},
+		Subscript: []byte{},
 		Amt:    69,
 		Height: 1337,
 	}
 	bufWriter := &bytes.Buffer{}
-	n, err := utxo1.WriteTo(bufWriter)
+	written, err := utxo1.WriteTo(bufWriter)
 	if err != nil {
 		t.Error(err)
 	}
-	if int(n) != binary.Size(utxo1) {
-		t.Error("Writing Utxo: Size Mismatch")
-	}
 	utxoBytes := bufWriter.Bytes()
 
 	utxo2 := new(Utxo)
-	n, err = utxo2.ReadFrom(bytes.NewBuffer(utxoBytes))
+	read, err := utxo2.ReadFrom(bytes.NewBuffer(utxoBytes))
 	if err != nil {
 		t.Error(err)
 	}
-	if int(n) != binary.Size(utxo2) {
+	if written != read {
-		t.Error("Reading Utxo: Size Mismatch")
+		t.Error("Reading and Writing Utxo: Size Mismatch")
 	}
 
 	if !reflect.DeepEqual(utxo1, utxo2) {
@@ -129,7 +125,7 @@ func TestUtxoWriteRead(t *testing.T) {
 	truncatedReadBuf := bytes.NewBuffer(utxoBytes)
 	truncatedReadBuf.Truncate(btcwire.HashSize)
 	utxo3 := new(Utxo)
-	n, err = utxo3.ReadFrom(truncatedReadBuf)
+	n, err := utxo3.ReadFrom(truncatedReadBuf)
 	if err != io.EOF {
 		t.Error("Expected err = io.EOF reading from truncated buffer.")
 	}
@@ -146,7 +142,8 @@ func TestUtxoStoreWriteRead(t *testing.T) {
 			utxo.Out.Hash[j] = byte(i)
 		}
 		utxo.Out.Index = uint32(i + 1)
-		utxo.Amt = int64(i + 2)
+		utxo.Subscript = []byte{}
+		utxo.Amt = uint64(i + 2)
 		utxo.Height = int64(i + 3)
 		store1.Confirmed = append(store1.Confirmed, utxo)
 	}
@@ -156,7 +153,8 @@ func TestUtxoStoreWriteRead(t *testing.T) {
 			utxo.Out.Hash[j] = byte(i)
 		}
 		utxo.Out.Index = uint32(i + 1)
-		utxo.Amt = int64(i + 2)
+		utxo.Subscript = []byte{}
+		utxo.Amt = uint64(i + 2)
 		utxo.Height = int64(i + 3)
 		store1.Unconfirmed = append(store1.Unconfirmed, utxo)
 	}
@@ -166,9 +164,6 @@ func TestUtxoStoreWriteRead(t *testing.T) {
 	if err != nil {
 		t.Error(err)
 	}
-	if n != 20*(1+int64(utxoByteSize)) {
-		t.Error("Incorrect number of bytes written.")
-	}
 
 	storeBytes := bufWriter.Bytes()
 
@@ -182,17 +177,18 @@ func TestUtxoStoreWriteRead(t *testing.T) {
 	}
 
 	if !reflect.DeepEqual(store1, store2) {
+		spew.Dump(store1, store2)
 		t.Error("Stores do not match.")
 	}
 
 	truncatedReadBuf := bytes.NewBuffer(storeBytes)
-	truncatedReadBuf.Truncate(10*(1+utxoByteSize) + btcwire.HashSize)
+	truncatedReadBuf.Truncate(100)
 	store3 := new(UtxoStore)
 	n, err = store3.ReadFrom(truncatedReadBuf)
 	if err != io.EOF {
 		t.Error("Expected err = io.EOF reading from truncated buffer.")
 	}
-	if n != 10*(1+int64(utxoByteSize))+btcwire.HashSize {
+	if n != 100 {
 		t.Error("Incorrect number of bytes read from truncated buffer.")
 	}
 }