lightningd: don't try to re-xmit funding tx for already-confirmed channels.

`resend_opening_transactions` runs at startup before `begin_topology()`, so `channel->depth` is still 0 (its DB-load default) for every channel.
The `depth != 0` guard was therefore a no-op, and we issued a `sendrawtransaction` for every committed channel on every restart. For long-confirmed channels bitcoind replies with error `-27` ("Transaction outputs already in utxo set"), surfacing as an `UNUSUAL` log on every startup.

Gate on channel state instead: only the three states where the funding or splice tx can still be unconfirmed
(`CHANNELD_AWAITING_LOCKIN`, DUALOPEND_AWAITING_LOCKIN`, `CHANNELD_AWAITING_SPLICE`) qualify for rebroadcast.

Changelog-Fixed: lightningd: don't spuriously try to re-broadcast funding txs of already-confirmed channels on startup.

Author: enaples

lightningd/peer_control.c

@@ -565,12 +565,16 @@ void resend_opening_transactions(struct lightningd *ld)
 	     peer = peer_node_id_map_next(ld->peers, &it)) {
 		list_for_each(&peer->channels, channel, list) {
 			struct wally_tx *wtx;
-			if (channel_state_uncommitted(channel->state))
+			/* Only states where the funding/splice tx might
+			 * still be unconfirmed.  channel->depth can't be
+			 * used here: it's reset to 0 on DB load and only
+			 * repopulated once topology starts. */
+			if (channel->state != CHANNELD_AWAITING_LOCKIN
+			    && channel->state != DUALOPEND_AWAITING_LOCKIN
+			    && channel->state != CHANNELD_AWAITING_SPLICE)
 				continue;
 			if (!channel->funding_psbt || channel->withheld)
 				continue;
-			if (channel->depth != 0)
-				continue;
 			wtx = psbt_final_tx(tmpctx, channel->funding_psbt);
 			if (!wtx)
 				continue;

tests/test_opening.py

@@ -3087,5 +3087,5 @@ def test_no_retransmit_confirmed_funding(node_factory):
     l1.restart()
 
     # Should not have attempted (and failed) to re-broadcast the funding tx.
-    assert l1.daemon.is_in_log('Failed to re-transmit funding tx')
+    assert not l1.daemon.is_in_log('Failed to re-transmit funding tx')
     assert not l1.daemon.is_in_log('Successfully rexmitted funding tx')