channeld: use fee_states internally.

This is an intermediary step: we still don't save it to the database,
but we do use the fee_states struct to track it internally.

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

channeld/full_channel.c

@@ -9,6 +9,7 @@
 #include <channeld/commit_tx.h>
 #include <channeld/full_channel.h>
 #include <common/channel_config.h>
+#include <common/fee_states.h>
 #include <common/htlc.h>
 #include <common/htlc_trim.h>
 #include <common/htlc_tx.h>
@@ -101,13 +102,16 @@ struct channel *new_full_channel(const tal_t *ctx,
 				 bool option_static_remotekey,
 				 enum side funder)
 {
+	/* FIXME: Support full feestates! */
+	struct fee_states *fee_states = new_fee_states(NULL, funder,
+						       &feerate_per_kw[funder]);
 	struct channel *channel = new_initial_channel(ctx,
 						      funding_txid,
 						      funding_txout,
 						      minimum_depth,
 						      funding,
 						      local_msat,
-						      feerate_per_kw[LOCAL],
+						      take(fee_states),
 						      local, remote,
 						      local_basepoints,
 						      remote_basepoints,
@@ -117,8 +121,6 @@ struct channel *new_full_channel(const tal_t *ctx,
 						      funder);
 
 	if (channel) {
-		/* Feerates can be different. */
-		channel->view[REMOTE].feerate_per_kw = feerate_per_kw[REMOTE];
 		channel->htlcs = tal(channel, struct htlc_map);
 		htlc_map_init(channel->htlcs);
 		memleak_add_helper(channel->htlcs, memleak_help_htlcmap);
@@ -812,6 +814,37 @@ static void htlc_incstate(struct channel *channel,
 	}
 }
 
+/* Returns true if a change was made. */
+static bool fee_incstate(struct channel *channel,
+			 enum side sidechanged,
+			 enum htlc_state hstate)
+{
+	int preflags, postflags;
+	const int committed_f = HTLC_FLAG(sidechanged, HTLC_F_COMMITTED);
+
+	preflags = htlc_state_flags(hstate);
+	postflags = htlc_state_flags(hstate + 1);
+
+	/* You can't change sides. */
+	assert((preflags & (HTLC_LOCAL_F_OWNER|HTLC_REMOTE_F_OWNER))
+	       == (postflags & (HTLC_LOCAL_F_OWNER|HTLC_REMOTE_F_OWNER)));
+
+	/* These only advance through ADDING states. */
+	if (!(htlc_state_flags(hstate) & HTLC_ADDING))
+		return false;
+
+	if (!inc_fee_state(channel->fee_states, hstate))
+		return false;
+
+	if (!(preflags & committed_f) && (postflags & committed_f))
+		status_debug("Feerate: %s->%s %s now %u",
+			     htlc_state_name(hstate),
+			     htlc_state_name(hstate+1),
+			     side_to_str(sidechanged),
+			     *channel->fee_states->feerate[hstate+1]);
+	return true;
+}
+
 /* Returns flags which were changed. */
 static int change_htlcs(struct channel *channel,
 			enum side sidechanged,
@@ -855,6 +888,13 @@ static int change_htlcs(struct channel *channel,
 		}
 	}
 
+	/* Update fees. */
+	for (i = 0; i < n_hstates; i++) {
+		if (fee_incstate(channel, sidechanged, htlc_states[i]))
+			cflags |= (htlc_state_flags(htlc_states[i])
+				   ^ htlc_state_flags(htlc_states[i]+1));
+	}
+
 	return cflags;
 }
 
@@ -967,7 +1007,8 @@ bool channel_update_feerate(struct channel *channel, u32 feerate_per_kw)
 	status_debug("Setting %s feerate to %u",
 		     side_to_str(!channel->funder), feerate_per_kw);
 
-	channel->view[!channel->funder].feerate_per_kw = feerate_per_kw;
+	start_fee_update(channel->fee_states, channel->funder, feerate_per_kw);
+
 	channel->changes_pending[!channel->funder] = true;
 	return true;
 }
@@ -1011,17 +1052,6 @@ bool channel_rcvd_revoke_and_ack(struct channel *channel,
 	if (change & HTLC_LOCAL_F_PENDING)
 		channel->changes_pending[LOCAL] = true;
 
-	/* For funder, ack also means time to apply new feerate locally. */
-	if (channel->funder == LOCAL &&
-	    (channel->view[LOCAL].feerate_per_kw
-	     != channel->view[REMOTE].feerate_per_kw)) {
-		status_debug("Applying feerate %u to LOCAL",
-			     channel->view[REMOTE].feerate_per_kw);
-		channel->view[LOCAL].feerate_per_kw
-			= channel->view[REMOTE].feerate_per_kw;
-		channel->changes_pending[LOCAL] = true;
-	}
-
 	return channel->changes_pending[LOCAL];
 }
 
@@ -1062,17 +1092,6 @@ bool channel_sending_revoke_and_ack(struct channel *channel)
 	if (change & HTLC_REMOTE_F_PENDING)
 		channel->changes_pending[REMOTE] = true;
 
-	/* For non-funder, sending ack means we apply any fund changes to them */
-	if (channel->funder == REMOTE
-	    && (channel->view[LOCAL].feerate_per_kw
-		!= channel->view[REMOTE].feerate_per_kw)) {
-		status_debug("Applying feerate %u to REMOTE",
-			     channel->view[LOCAL].feerate_per_kw);
-		channel->view[REMOTE].feerate_per_kw
-			= channel->view[LOCAL].feerate_per_kw;
-		channel->changes_pending[REMOTE] = true;
-	}
-
 	return channel->changes_pending[REMOTE];
 }
 

channeld/test/run-full_channel.c

@@ -1,3 +1,4 @@
+#include "../../common/fee_states.c"
 #include "../../common/initial_channel.c"
 #include "../../common/keyset.c"
 #include "../full_channel.c"
@@ -629,8 +630,10 @@ int main(void)
 	for (i = 0; i < ARRAY_SIZE(feerates); i++) {
 		feerate_per_kw[LOCAL] = feerate_per_kw[REMOTE] = feerates[i];
 
-		lchannel->view[LOCAL].feerate_per_kw = feerate_per_kw[LOCAL];
+		*lchannel->fee_states->feerate[SENT_ADD_ACK_REVOCATION]
-		rchannel->view[REMOTE].feerate_per_kw = feerate_per_kw[REMOTE];
+			= feerate_per_kw[LOCAL];
+		*rchannel->fee_states->feerate[RCVD_ADD_ACK_REVOCATION]
+			= feerate_per_kw[REMOTE];
 
 		raw_tx = commit_tx(
 		    tmpctx, &funding_txid, funding_output_index,

common/initial_channel.c

@@ -1,7 +1,9 @@
 #include <assert.h>
 #include <bitcoin/chainparams.h>
 #include <bitcoin/script.h>
+#include <ccan/array_size/array_size.h>
 #include <ccan/tal/str/str.h>
+#include <common/fee_states.h>
 #include <common/initial_channel.h>
 #include <common/initial_commit_tx.h>
 #include <common/keyset.h>
@@ -14,7 +16,7 @@ struct channel *new_initial_channel(const tal_t *ctx,
 				    u32 minimum_depth,
 				    struct amount_sat funding,
 				    struct amount_msat local_msatoshi,
-				    u32 feerate_per_kw,
+				    const struct fee_states *fee_states TAKES,
 				    const struct channel_config *local,
 				    const struct channel_config *remote,
 				    const struct basepoints *local_basepoints,
@@ -44,9 +46,8 @@ struct channel *new_initial_channel(const tal_t *ctx,
 	channel->changes_pending[LOCAL] = channel->changes_pending[REMOTE]
 		= false;
 
-	channel->view[LOCAL].feerate_per_kw
+	/* takes() if necessary */
-		= channel->view[REMOTE].feerate_per_kw
+	channel->fee_states = dup_fee_states(channel, fee_states);
-		= feerate_per_kw;
 
 	channel->view[LOCAL].owed[LOCAL]
 		= channel->view[REMOTE].owed[LOCAL]
@@ -112,22 +113,20 @@ struct bitcoin_tx *initial_channel_tx(const tal_t *ctx,
 
 u32 channel_feerate(const struct channel *channel, enum side side)
 {
-	return channel->view[side].feerate_per_kw;
+	return get_feerate(channel->fee_states, channel->funder, side);
 }
 
 static char *fmt_channel_view(const tal_t *ctx, const struct channel_view *view)
 {
-	return tal_fmt(ctx, "{ feerate_per_kw=%"PRIu32","
+	return tal_fmt(ctx, "{ owed_local=%s,"
-		       " owed_local=%s,"
 		       " owed_remote=%s }",
-		       view->feerate_per_kw,
 		       type_to_string(tmpctx, struct amount_msat,
 				      &view->owed[LOCAL]),
 		       type_to_string(tmpctx, struct amount_msat,
 				      &view->owed[REMOTE]));
 }
 
-/* FIXME: This should reference HTLCs somehow. */
+/* FIXME: This should reference HTLCs somehow, and feerates! */
 static char *fmt_channel(const tal_t *ctx, const struct channel *channel)
 {
 	return tal_fmt(ctx, "{ funding=%s,"

common/initial_channel.h

@@ -20,9 +20,6 @@ struct fulfilled_htlc;
 
 /* View from each side */
 struct channel_view {
-	/* Current feerate in satoshis per 1000 weight. */
-	u32 feerate_per_kw;
-
 	/* How much is owed to each side (includes pending changes) */
 	struct amount_msat owed[NUM_SIDES];
 };
@@ -59,6 +56,9 @@ struct channel {
 	/* Do we have changes pending for ourselves/other? */
 	bool changes_pending[NUM_SIDES];
 
+	/* Fee changes, some which may be in transit */
+	struct fee_states *fee_states;
+
 	/* What it looks like to each side. */
 	struct channel_view view[NUM_SIDES];
 
@@ -74,8 +74,7 @@ struct channel {
  * @minimum_depth: The minimum confirmations needed for funding transaction.
  * @funding_satoshis: The commitment transaction amount.
  * @local_msatoshi: The amount for the local side (remainder goes to remote)
- * @feerate_per_kw: feerate per kiloweight (satoshis) for the commitment
+ * @fee_states: The fee update states.
- *   transaction and HTLCS (at this stage, same for both sides)
  * @local: local channel configuration
  * @remote: remote channel configuration
  * @local_basepoints: local basepoints.
@@ -92,7 +91,7 @@ struct channel *new_initial_channel(const tal_t *ctx,
 				    u32 minimum_depth,
 				    struct amount_sat funding,
 				    struct amount_msat local_msatoshi,
-				    u32 feerate_per_kw,
+				    const struct fee_states *fee_states TAKES,
 				    const struct channel_config *local,
 				    const struct channel_config *remote,
 				    const struct basepoints *local_basepoints,

devtools/Makefile

@@ -16,8 +16,10 @@ DEVTOOLS_COMMON_OBJS :=				\
 	common/crypto_state.o			\
 	common/decode_array.o			\
 	common/features.o			\
+	common/fee_states.o			\
 	common/gossip_rcvd_filter.o		\
 	common/hash_u5.o			\
+	common/htlc_state.o			\
 	common/memleak.o			\
 	common/node_id.o			\
 	common/onion.o				\

openingd/openingd.c

@@ -20,6 +20,7 @@
 #include <common/crypto_sync.h>
 #include <common/derive_basepoints.h>
 #include <common/features.h>
+#include <common/fee_states.h>
 #include <common/funding_tx.h>
 #include <common/gen_peer_status_wire.h>
 #include <common/gossip_rcvd_filter.h>
@@ -670,7 +671,8 @@ static bool funder_finalize_channel_setup(struct state *state,
 					     state->minimum_depth,
 					     state->funding,
 					     local_msat,
-					     state->feerate_per_kw,
+					     take(new_fee_states(NULL, LOCAL,
+								 &state->feerate_per_kw)),
 					     &state->localconf,
 					     &state->remoteconf,
 					     &state->our_points,
@@ -1136,7 +1138,8 @@ static u8 *fundee_channel(struct state *state, const u8 *open_channel_msg)
 					     state->minimum_depth,
 					     state->funding,
 					     state->push_msat,
-					     state->feerate_per_kw,
+					     take(new_fee_states(NULL, REMOTE,
+								 &state->feerate_per_kw)),
 					     &state->localconf,
 					     &state->remoteconf,
 					     &state->our_points, &theirs,

tests/test_connection.py

@@ -1499,7 +1499,7 @@ def test_update_fee_reconnect(node_factory, bitcoind):
     l1.daemon.wait_for_log(r'dev_disconnect: \+WIRE_COMMITMENT_SIGNED')
 
     # Wait for reconnect....
-    l1.daemon.wait_for_log('Applying feerate 14000 to LOCAL')
+    l1.daemon.wait_for_log('Feerate:.*LOCAL now 14000')
 
     l1.pay(l2, 200000000)
     l2.pay(l1, 100000000)