lnwallet: move txout serialization out of lnwire

lnwallet/signdescriptor.go

@@ -5,7 +5,6 @@ import (
 	"errors"
 	"io"
 
-	"github.com/lightningnetwork/lnd/lnwire"
 	"github.com/roasbeef/btcd/btcec"
 	"github.com/roasbeef/btcd/txscript"
 	"github.com/roasbeef/btcd/wire"
@@ -104,7 +103,7 @@ func WriteSignDescriptor(w io.Writer, sd *SignDescriptor) error {
 		return err
 	}
 
-	if err := lnwire.WriteTxOut(w, sd.Output); err != nil {
+	if err := writeTxOut(w, sd.Output); err != nil {
 		return err
 	}
 
@@ -174,7 +173,7 @@ func ReadSignDescriptor(r io.Reader, sd *SignDescriptor) error {
 	sd.WitnessScript = witnessScript
 
 	txOut := &wire.TxOut{}
-	if err := lnwire.ReadTxOut(r, txOut); err != nil {
+	if err := readTxOut(r, txOut); err != nil {
 		return err
 	}
 	sd.Output = txOut

lnwallet/txout.go

@@ -0,0 +1,46 @@
+package lnwallet
+
+import (
+	"encoding/binary"
+	"io"
+
+	"github.com/roasbeef/btcd/wire"
+)
+
+// writeTxOut serializes a wire.TxOut struct into the passed io.Writer stream.
+func writeTxOut(w io.Writer, txo *wire.TxOut) error {
+	var scratch [8]byte
+
+	binary.BigEndian.PutUint64(scratch[:], uint64(txo.Value))
+	if _, err := w.Write(scratch[:]); err != nil {
+		return err
+	}
+
+	if err := wire.WriteVarBytes(w, 0, txo.PkScript); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+// readTxOut deserializes a wire.TxOut struct from the passed io.Reader stream.
+func readTxOut(r io.Reader, txo *wire.TxOut) error {
+	var scratch [8]byte
+
+	if _, err := io.ReadFull(r, scratch[:]); err != nil {
+		return err
+	}
+	value := int64(binary.BigEndian.Uint64(scratch[:]))
+
+	pkScript, err := wire.ReadVarBytes(r, 0, 80, "pkScript")
+	if err != nil {
+		return err
+	}
+
+	*txo = wire.TxOut{
+		Value:    value,
+		PkScript: pkScript,
+	}
+
+	return nil
+}

lnwallet/txout_test.go

@@ -0,0 +1,46 @@
+package lnwallet
+
+import (
+	"bytes"
+	"reflect"
+	"testing"
+
+	"github.com/roasbeef/btcd/wire"
+)
+
+func TestTxOutSerialization(t *testing.T) {
+	txo := wire.TxOut{
+		Value: 1e7,
+		PkScript: []byte{
+			0x41, // OP_DATA_65
+			0x04, 0xd6, 0x4b, 0xdf, 0xd0, 0x9e, 0xb1, 0xc5,
+			0xfe, 0x29, 0x5a, 0xbd, 0xeb, 0x1d, 0xca, 0x42,
+			0x81, 0xbe, 0x98, 0x8e, 0x2d, 0xa0, 0xb6, 0xc1,
+			0xc6, 0xa5, 0x9d, 0xc2, 0x26, 0xc2, 0x86, 0x24,
+			0xe1, 0x81, 0x75, 0xe8, 0x51, 0xc9, 0x6b, 0x97,
+			0x3d, 0x81, 0xb0, 0x1c, 0xc3, 0x1f, 0x04, 0x78,
+			0x34, 0xbc, 0x06, 0xd6, 0xd6, 0xed, 0xf6, 0x20,
+			0xd1, 0x84, 0x24, 0x1a, 0x6a, 0xed, 0x8b, 0x63,
+			0xa6, // 65-byte signature
+			0xac, // OP_CHECKSIG
+		},
+	}
+
+	var buf bytes.Buffer
+
+	if err := writeTxOut(&buf, &txo); err != nil {
+		t.Fatalf("unable to serialize txout: %v", err)
+	}
+
+	var deserializedTxo wire.TxOut
+	if err := readTxOut(&buf, &deserializedTxo); err != nil {
+		t.Fatalf("unable to deserialize txout: %v", err)
+	}
+
+	if !reflect.DeepEqual(txo, deserializedTxo) {
+		t.Fatalf("original and deserialized txouts are different:\n"+
+			"original     : %+v\n"+
+			"deserialized : %+v\n",
+			txo, deserializedTxo)
+	}
+}