db: make db_set_visible_state called from within transaction.

We want to do this atomically; this is the first step.

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

daemon/db.c

@@ -1350,13 +1350,13 @@ void db_set_anchor(struct peer *peer)
 	tal_free(ctx);
 }
 
-bool db_set_visible_state(struct peer *peer)
+void db_set_visible_state(struct peer *peer)
 {
-	const char *errmsg, *ctx = tal_tmpctx(peer);
+	const char *ctx = tal_tmpctx(peer);
 	const char *peerid = pubkey_to_hexstr(ctx, peer->dstate->secpctx, peer->id);
 
 	log_debug(peer->log, "%s(%s)", __func__, peerid);
-	db_start_transaction(peer);
+	assert(peer->dstate->db->in_transaction);
 
 	db_exec(__func__, peer->dstate, 
 		"INSERT INTO their_visible_state VALUES (x'%s', %s, x'%s', x'%s', %u, %u, %"PRIu64", x'%s');",
@@ -1372,10 +1372,7 @@ bool db_set_visible_state(struct peer *peer)
 		tal_hexstr(ctx, &peer->remote.next_revocation_hash,
 			   sizeof(peer->remote.next_revocation_hash)));
 
-	errmsg = db_commit_transaction(peer);
-
 	tal_free(ctx);
-	return !errmsg;
 }
 
 void db_update_next_revocation_hash(struct peer *peer)

daemon/db.h

@@ -7,7 +7,6 @@
 void db_init(struct lightningd_state *dstate);
 
 bool db_create_peer(struct peer *peer);
-bool db_set_visible_state(struct peer *peer);
 
 void db_start_transaction(struct peer *peer);
 void db_abort_transaction(struct peer *peer);
@@ -44,6 +43,7 @@ bool db_remove_invoice(struct lightningd_state *dstate,
  * which have to be inside transaction anyway. */
 
 /* Must be inside transaction. */
+void db_set_visible_state(struct peer *peer);
 void db_set_anchor(struct peer *peer);
 void db_new_htlc(struct peer *peer, const struct htlc *htlc);
 void db_new_feechange(struct peer *peer, const struct feechange *feechange);

state.c

@@ -32,7 +32,9 @@ static Pkt *init_from_pkt_open(struct peer *peer, const Pkt *pkt)
 	if (err)
 		return err;
 
-	if (!db_set_visible_state(peer))
+	db_start_transaction(peer);
+	db_set_visible_state(peer);
+	if (db_commit_transaction(peer) != NULL)
 		return pkt_err(peer, "Database error");
 
 	/* Set up their commit info now: rest gets done in setup_first_commit