lightningd/htlc_wire: marshal/unmashal bitcoin tx.

We want to keep the last valid tx, and its signature, for broadcast.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

lightningd/htlc_wire.c

@@ -1,3 +1,4 @@
+#include <bitcoin/tx.h>
 #include <ccan/array_size/array_size.h>
 #include <ccan/crypto/shachain/shachain.h>
 #include <lightningd/htlc_wire.h>
@@ -58,6 +59,14 @@ void towire_shachain(u8 **pptr, const struct shachain *shachain)
 	}
 }
 
+void towire_bitcoin_tx(u8 **pptr, const struct bitcoin_tx *tx)
+{
+	u8 *txlin = linearize_tx(NULL, tx);
+
+	towire(pptr, txlin, tal_len(txlin));
+	tal_free(txlin);
+}
+
 void fromwire_added_htlc(const u8 **cursor, size_t *max,
 			 struct added_htlc *added)
 {
@@ -131,3 +140,13 @@ void fromwire_shachain(const u8 **cursor, size_t *max,
 		fromwire_sha256(cursor, max, &shachain->known[i].hash);
 	}
 }
+
+void fromwire_bitcoin_tx(const u8 **cursor, size_t *max, struct bitcoin_tx *tx)
+{
+	/* FIXME: We'd really expect to allocate tx ourselves, but
+	 * for the sake of simple structures, we don't write the
+	 * generator that way. */
+	struct bitcoin_tx *tx2 = pull_bitcoin_tx(tx, cursor, max);
+	if (tx2)
+		*tx = *tx2;
+}

lightningd/htlc_wire.h

@@ -7,6 +7,7 @@
 #include <lightningd/sphinx.h>
 #include <wire/gen_onion_wire.h>
 
+struct bitcoin_tx;
 struct shachain;
 
 /* These are how we communicate about HTLC state to the master daemon */
@@ -41,6 +42,7 @@ void towire_changed_htlc(u8 **pptr, const struct changed_htlc *changed);
 void towire_htlc_state(u8 **pptr, const enum htlc_state hstate);
 void towire_side(u8 **pptr, const enum side side);
 void towire_shachain(u8 **pptr, const struct shachain *shachain);
+void towire_bitcoin_tx(u8 **pptr, const struct bitcoin_tx *tx);
 
 void fromwire_added_htlc(const u8 **cursor, size_t *max,
 			 struct added_htlc *added);
@@ -54,4 +56,5 @@ enum htlc_state fromwire_htlc_state(const u8 **cursor, size_t *max);
 enum side fromwire_side(const u8 **cursor, size_t *max);
 void fromwire_shachain(const u8 **cursor, size_t *max,
 		       struct shachain *shachain);
+void fromwire_bitcoin_tx(const u8 **cursor, size_t *max, struct bitcoin_tx *tx);
 #endif /* LIGHTNING_LIGHTNINGD_HTLC_WIRE_H */