channel: change initialization to have explicit local amount, and commot indices.

This is useful for restoration.

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

lightningd/channel.c

@@ -137,8 +137,10 @@ struct channel *new_channel(const tal_t *ctx,
 			    const struct sha256_double *funding_txid,
 			    unsigned int funding_txout,
 			    u64 funding_satoshis,
-			    u64 push_msat,
+			    u64 local_msatoshi,
 			    u32 feerate_per_kw,
+			    u64 local_commit_index,
+			    u64 remote_commit_index,
 			    const struct channel_config *local,
 			    const struct channel_config *remote,
 			    const struct basepoints *local_basepoints,
@@ -155,7 +157,7 @@ struct channel *new_channel(const tal_t *ctx,
 		return tal_free(channel);
 
 	channel->funding_msat = funding_satoshis * 1000;
-	if (push_msat > channel->funding_msat)
+	if (local_msatoshi > channel->funding_msat)
 		return tal_free(channel);
 
 	channel->funder = funder;
@@ -169,16 +171,15 @@ struct channel *new_channel(const tal_t *ctx,
 		= channel->view[REMOTE].feerate_per_kw
 		= feerate_per_kw;
 
-	channel->view[funder].owed_msat[funder]
-		= channel->view[!funder].owed_msat[funder]
-		= channel->funding_msat - push_msat;
-	channel->view[funder].owed_msat[!funder]
-		= channel->view[!funder].owed_msat[!funder]
-		= push_msat;
+	channel->view[LOCAL].owed_msat[LOCAL]
+		= channel->view[REMOTE].owed_msat[LOCAL]
+		= local_msatoshi;
+	channel->view[REMOTE].owed_msat[REMOTE]
+		= channel->view[LOCAL].owed_msat[REMOTE]
+		= channel->funding_msat - local_msatoshi;
 
-	channel->view[LOCAL].commitment_number
-		= channel->view[REMOTE].commitment_number
-		= 0;
+	channel->view[LOCAL].commitment_number = local_commit_index;
+	channel->view[REMOTE].commitment_number = remote_commit_index;
 
 	channel->basepoints[LOCAL] = *local_basepoints;
 	channel->basepoints[REMOTE] = *remote_basepoints;

lightningd/channel.h

@@ -124,8 +124,10 @@ static inline u16 to_self_delay(const struct channel *channel, enum side side)
  * @funding_txid: The commitment transaction id.
  * @funding_txout: The commitment transaction output number.
  * @funding_satoshis: The commitment transaction amount.
- * @push_msat: The amount the initator gives to the other side.
+ * @local_msatoshi: The amount for the local side (remainder goes to remote)
  * @feerate_per_kw: feerate per kiloweight (satoshis)
+ * @local_commit_index: local commitment number
+ * @remote_commit_index: remote commitment number
  * @local: local channel configuration
  * @remote: remote channel configuration
  * @local_basepoints: local basepoints.
@@ -140,8 +142,10 @@ struct channel *new_channel(const tal_t *ctx,
 			    const struct sha256_double *funding_txid,
 			    unsigned int funding_txout,
 			    u64 funding_satoshis,
-			    u64 push_msat,
+			    u64 local_msatoshi,
 			    u32 feerate_per_kw,
+			    u64 local_commit_index,
+			    u64 remote_commit_index,
 			    const struct channel_config *local,
 			    const struct channel_config *remote,
 			    const struct basepoints *local_basepoints,

lightningd/channel/channel.c

@@ -1216,6 +1216,7 @@ static void init_channel(struct peer *peer)
 	struct basepoints points[NUM_SIDES];
 	u64 funding_satoshi, push_msat;
 	u16 funding_txout;
+	u64 local_msatoshi;
 	struct pubkey funding_pubkey[NUM_SIDES];
 	struct sha256_double funding_txid;
 	bool am_funder;
@@ -1258,8 +1259,16 @@ static void init_channel(struct peer *peer)
 		     type_to_string(trc, struct pubkey,
 				    &peer->old_per_commit[LOCAL]));
 
+	if (am_funder)
+		local_msatoshi = funding_satoshi * 1000 - push_msat;
+	else
+		local_msatoshi = push_msat;
+
 	peer->channel = new_channel(peer, &funding_txid, funding_txout,
-				    funding_satoshi, push_msat, peer->fee_base,
+				    funding_satoshi,
+				    local_msatoshi,
+				    peer->fee_base,
+				    0, 0,
 				    &peer->conf[LOCAL], &peer->conf[REMOTE],
 				    &points[LOCAL], &points[REMOTE],
 				    &funding_pubkey[LOCAL],

lightningd/opening/opening.c

@@ -339,8 +339,10 @@ static u8 *funder_channel(struct state *state,
 				     &state->funding_txid,
 				     state->funding_txout,
 				     state->funding_satoshis,
-				     state->push_msat,
+				     state->funding_satoshis * 1000
+				     - state->push_msat,
 				     state->feerate_per_kw,
+				     0, 0,
 				     &state->localconf,
 				     state->remoteconf,
 				     ours, &theirs,
@@ -595,6 +597,7 @@ static u8 *fundee_channel(struct state *state,
 				     state->funding_satoshis,
 				     state->push_msat,
 				     state->feerate_per_kw,
+				     0, 0,
 				     &state->localconf,
 				     state->remoteconf,
 				     ours, &theirs,

lightningd/test/run-channel.c

@@ -403,6 +403,8 @@ int main(void)
 
 	/* BOLT #3:
 	 *
+	 *    commitment_number: 42
+	 *...
 	 *    name: simple commitment tx with no HTLCs
 	 *    to_local_msat: 7000000000
 	 *    to_remote_msat: 3000000000
@@ -413,28 +415,23 @@ int main(void)
 	to_remote_msat = 3000000000;
 	feerate_per_kw = 15000;
 	lchannel = new_channel(tmpctx, &funding_txid, funding_output_index,
-			       funding_amount_satoshi, to_remote_msat,
+			       funding_amount_satoshi, to_local_msat,
 			       feerate_per_kw,
+			       42, 0,
 			       local_config,
 			       remote_config,
 			       &localbase, &remotebase,
 			       &local_funding_pubkey, &remote_funding_pubkey,
 			       LOCAL);
-
 	rchannel = new_channel(tmpctx, &funding_txid, funding_output_index,
 			       funding_amount_satoshi, to_remote_msat,
 			       feerate_per_kw,
+			       0, 42,
 			       remote_config,
 			       local_config,
 			       &remotebase, &localbase,
 			       &remote_funding_pubkey, &local_funding_pubkey,
 			       REMOTE);
-	/* BOLT #3:
-	 *
-	 *     commitment_number: 42
-	 */
-	lchannel->view[LOCAL].commitment_number
-		= rchannel->view[REMOTE].commitment_number = 42;
 
 	/* BOLT #3:
 	 *