Modified fromwire_witscript to return NULL instead of struct w/ NULL ptr.

Author: ksedgwic

wire/fromwire.c

@@ -403,14 +403,13 @@ struct bitcoin_tx_output *fromwire_bitcoin_tx_output(const tal_t *ctx,
 
 struct witscript *fromwire_witscript(const tal_t *ctx, const u8 **cursor, size_t *max)
 {
-	struct witscript *retval = tal(ctx, struct witscript);
+	struct witscript *retval;
 	u16 len = fromwire_u16(cursor, max);
-	if (len == 0) {
-		retval->ptr = NULL;
-	} else {
-		retval->ptr = tal_arr(retval, u8, len);
-		fromwire_u8_array(cursor, max, retval->ptr, len);
-	}
+	if (!len)
+		return NULL;
+	retval = tal(ctx, struct witscript);
+	retval->ptr = tal_arr(retval, u8, len);
+	fromwire_u8_array(cursor, max, retval->ptr, len);
 	return retval;
 }
 

wire/towire.c

@@ -264,9 +264,10 @@ void towire_bitcoin_tx_output(u8 **pptr, const struct bitcoin_tx_output *output)
 
 void towire_witscript(u8 **pptr, const struct witscript *script)
 {
-	if (script == NULL || script->ptr == NULL) {
+	if (script == NULL) {
 		towire_u16(pptr, 0);
 	} else {
+		assert(script->ptr != NULL);
 		towire_u16(pptr, tal_count(script->ptr));
 		towire_u8_array(pptr, script->ptr, tal_count(script->ptr));
 	}