lightningd and routing: use struct amount_msat.

We use it in route_hop, and paper over it in the JSON APIs.

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

gossipd/routing.c

@@ -1559,7 +1559,7 @@ struct route_hop *get_route(const tal_t *ctx, struct routing_state *rstate,
 		c = &route[i]->half[idx];
 		hops[i].channel_id = route[i]->scid;
 		hops[i].nodeid = n->id;
-		hops[i].amount = total_amount;
+		hops[i].amount.millisatoshis = total_amount;
 		hops[i].delay = total_delay;
 		hops[i].direction = idx;
 		total_amount += connection_fee(c, total_amount);

gossipd/routing.h

@@ -5,6 +5,7 @@
 #include <ccan/crypto/siphash24/siphash24.h>
 #include <ccan/htable/htable_type.h>
 #include <ccan/time/time.h>
+#include <common/amount.h>
 #include <gossipd/broadcast.h>
 #include <gossipd/gossip_constants.h>
 #include <gossipd/gossip_store.h>
@@ -205,7 +206,7 @@ struct route_hop {
 	struct short_channel_id channel_id;
 	int direction;
 	struct pubkey nodeid;
-	u64 amount;
+	struct amount_msat amount;
 	u32 delay;
 };
 

lightningd/gossip_control.c

@@ -10,6 +10,7 @@
 #include <ccan/fdpass/fdpass.h>
 #include <ccan/take/take.h>
 #include <ccan/tal/str/str.h>
+#include <common/amount.h>
 #include <common/features.h>
 #include <common/json_command.h>
 #include <common/json_escaped.h>
@@ -300,7 +301,7 @@ static struct command_result *json_getroute(struct command *cmd,
 	struct pubkey *destination;
 	struct pubkey *source;
 	const jsmntok_t *excludetok;
-	u64 *msatoshi;
+	struct amount_msat *msat;
 	unsigned *cltv;
 	double *riskfactor;
 	struct short_channel_id_dir *excluded;
@@ -315,7 +316,7 @@ static struct command_result *json_getroute(struct command *cmd,
 
 	if (!param(cmd, buffer, params,
 		   p_req("id", param_pubkey, &destination),
-		   p_req("msatoshi", param_u64, &msatoshi),
+		   p_req("msatoshi", param_msat, &msat),
 		   p_req("riskfactor", param_double, &riskfactor),
 		   p_opt_def("cltv", param_number, &cltv, 9),
 		   p_opt_def("fromid", param_pubkey, &source, ld->id),
@@ -353,7 +354,7 @@ static struct command_result *json_getroute(struct command *cmd,
 	}
 
 	u8 *req = towire_gossip_getroute_request(cmd, source, destination,
-						 *msatoshi,
+						 msat->millisatoshis,
 						 *riskfactor * 1000000.0,
 						 *cltv, fuzz,
 						 excluded,
@@ -398,7 +399,9 @@ static void json_listchannels_reply(struct subd *gossip UNUSED, const u8 *reply,
 				type_to_string(reply, struct short_channel_id,
 					       &entries[i].short_channel_id));
 		json_add_bool(response, "public", entries[i].public);
-		json_add_u64(response, "satoshis", entries[i].satoshis);
+		json_add_amount_sat(response,
+				    (struct amount_sat){ entries[i].satoshis },
+				    "satoshis", "amount_msat");
 		json_add_num(response, "message_flags", entries[i].message_flags);
 		json_add_num(response, "channel_flags", entries[i].channel_flags);
 		/* Prior to spec v0891374d47ddffa64c5a2e6ad151247e3d6b7a59, these two were a single u16 field */

lightningd/gossip_msg.c

@@ -65,7 +65,7 @@ void fromwire_route_hop(const u8 **pptr, size_t *max, struct route_hop *entry)
 	fromwire_pubkey(pptr, max, &entry->nodeid);
 	fromwire_short_channel_id(pptr, max, &entry->channel_id);
 	entry->direction = fromwire_u8(pptr, max);
-	entry->amount = fromwire_u64(pptr, max);
+	entry->amount = fromwire_amount_msat(pptr, max);
 	entry->delay = fromwire_u32(pptr, max);
 }
 
@@ -74,7 +74,7 @@ void towire_route_hop(u8 **pptr, const struct route_hop *entry)
 	towire_pubkey(pptr, &entry->nodeid);
 	towire_short_channel_id(pptr, &entry->channel_id);
 	towire_u8(pptr, entry->direction);
-	towire_u64(pptr, entry->amount);
+	towire_amount_msat(pptr, entry->amount);
 	towire_u32(pptr, entry->delay);
 }
 

lightningd/json.c

@@ -32,7 +32,7 @@ json_add_route_hop(struct json_stream *r, char const *n,
 	json_add_short_channel_id(r, "channel",
 				  &h->channel_id);
 	json_add_num(r, "direction", h->direction);
-	json_add_u64(r, "msatoshi", h->amount);
+	json_add_amount_msat(r, h->amount, "msatoshi", "amount_msat");
 	json_add_num(r, "delay", h->delay);
 	json_object_end(r);
 }

lightningd/pay.c

@@ -78,8 +78,12 @@ json_add_payment_fields(struct json_stream *response,
 	json_add_u64(response, "id", t->id);
 	json_add_hex(response, "payment_hash", &t->payment_hash, sizeof(t->payment_hash));
 	json_add_pubkey(response, "destination", &t->destination);
-	json_add_u64(response, "msatoshi", t->msatoshi);
-	json_add_u64(response, "msatoshi_sent", t->msatoshi_sent);
+	json_add_amount_msat(response,
+			     ((struct amount_msat){ t->msatoshi }),
+			     "msatoshi", "amount_msat");
+	json_add_amount_msat(response,
+			     ((struct amount_msat){ t->msatoshi_sent }),
+			     "msatoshi_sent", "amount_sent_msat");
 	json_add_u64(response, "created_at", t->timestamp);
 
 	switch (t->status) {
@@ -606,7 +610,7 @@ send_payment(struct lightningd *ld,
 	for (i = 0; i < n_hops - 1; i++) {
 		hop_data[i].realm = 0;
 		hop_data[i].channel_id = route[i+1].channel_id;
-		hop_data[i].amt_forward = route[i+1].amount;
+		hop_data[i].amt_forward = route[i+1].amount.millisatoshis;
 		hop_data[i].outgoing_cltv = base_expiry + route[i+1].delay;
 	}
 
@@ -615,7 +619,7 @@ send_payment(struct lightningd *ld,
 	hop_data[i].realm = 0;
 	hop_data[i].outgoing_cltv = base_expiry + route[i].delay;
 	memset(&hop_data[i].channel_id, 0, sizeof(struct short_channel_id));
-	hop_data[i].amt_forward = route[i].amount;
+	hop_data[i].amt_forward = route[i].amount.millisatoshis;
 
 	/* Now, do we already have a payment? */
 	payment = wallet_payment_by_hash(tmpctx, ld->wallet, rhash);
@@ -667,10 +671,11 @@ send_payment(struct lightningd *ld,
 				    sizeof(struct sha256), &path_secrets);
 	onion = serialize_onionpacket(tmpctx, packet);
 
-	log_info(ld->log, "Sending %"PRIu64" over %zu hops to deliver %"PRIu64"",
-		 route[0].amount, n_hops, msatoshi);
+	log_info(ld->log, "Sending %s over %zu hops to deliver %"PRIu64"",
+		 type_to_string(tmpctx, struct amount_msat, &route[0].amount),
+		 n_hops, msatoshi);
 
-	failcode = send_htlc_out(channel, route[0].amount,
+	failcode = send_htlc_out(channel, route[0].amount.millisatoshis,
 				 base_expiry + route[0].delay,
 				 rhash, onion, NULL, &hout);
 	if (failcode) {
@@ -705,7 +710,7 @@ send_payment(struct lightningd *ld,
 	payment->destination = ids[n_hops - 1];
 	payment->status = PAYMENT_PENDING;
 	payment->msatoshi = msatoshi;
-	payment->msatoshi_sent = route[0].amount;
+	payment->msatoshi_sent = route[0].amount.millisatoshis;
 	payment->timestamp = time_now().ts.tv_sec;
 	payment->payment_preimage = NULL;
 	payment->path_secrets = tal_steal(payment, path_secrets);
@@ -737,7 +742,7 @@ static struct command_result *json_sendpay(struct command *cmd,
 	size_t i;
 	struct sha256 *rhash;
 	struct route_hop *route;
-	u64 *msatoshi;
+	struct amount_msat *msat;
 	const char *description;
 	struct command_result *res;
 
@@ -745,7 +750,7 @@ static struct command_result *json_sendpay(struct command *cmd,
 		   p_req("route", param_array, &routetok),
 		   p_req("payment_hash", param_sha256, &rhash),
 		   p_opt("description", param_escaped_string, &description),
-		   p_opt("msatoshi", param_u64, &msatoshi),
+		   p_opt("msatoshi", param_msat, &msat),
 		   NULL))
 		return command_param_failed();
 
@@ -792,7 +797,7 @@ static struct command_result *json_sendpay(struct command *cmd,
 		if (!msat)
 			msat = amount_msat;
 
-		route[i].amount = msat->millisatoshis;
+		route[i].amount = *msat;
 		route[i].nodeid = *id;
 		route[i].delay = *delay;
 		route[i].channel_id = *channel;
@@ -805,17 +810,33 @@ static struct command_result *json_sendpay(struct command *cmd,
 	 * be from the msatoshi to twice msatoshi. */
 
 	/* if not: msatoshi <= finalhop.amount <= 2 * msatoshi, fail. */
-	if (msatoshi) {
-		if (!(*msatoshi <= route[routetok->size-1].amount &&
-		      route[routetok->size-1].amount <= 2 * *msatoshi)) {
+	if (msat) {
+		struct amount_msat two_times_final;
+
+		two_times_final.millisatoshis
+			= route[routetok->size-1].amount.millisatoshis * 2;
+		if (amount_msat_less(*msat, route[routetok->size-1].amount))
 			return command_fail(cmd, JSONRPC2_INVALID_PARAMS,
-					    "msatoshi %"PRIu64" out of range",
-					    *msatoshi);
-		}
+					    "msatoshi %s less than final %s",
+					    type_to_string(tmpctx,
+							   struct amount_msat,
+							   msat),
+					    type_to_string(tmpctx,
+							   struct amount_msat,
+							   &route[routetok->size-1].amount));
+		if (amount_msat_greater(*msat, two_times_final))
+			return command_fail(cmd, JSONRPC2_INVALID_PARAMS,
+					    "msatoshi %s more than twice final %s",
+					    type_to_string(tmpctx,
+							   struct amount_msat,
+							   msat),
+					    type_to_string(tmpctx,
+							   struct amount_msat,
+							   &route[routetok->size-1].amount));
 	}
 
 	res = send_payment(cmd->ld, cmd, rhash, route,
-			   msatoshi ? *msatoshi : route[routetok->size-1].amount,
+			   msat ? msat->millisatoshis : route[routetok->size-1].amount.millisatoshis,
 			   description);
 	if (res)
 		return res;

lightningd/peer_control.c

@@ -453,7 +453,9 @@ static void json_add_htlcs(struct lightningd *ld,
 		json_object_start(response, NULL);
 		json_add_string(response, "direction", "in");
 		json_add_u64(response, "id", hin->key.id);
-		json_add_u64(response, "msatoshi", hin->msatoshi);
+		json_add_amount_msat(response,
+				     (struct amount_msat){ hin->msatoshi },
+				     "msatoshi", "amount_msat");
 		json_add_u64(response, "expiry", hin->cltv_expiry);
 		json_add_hex(response, "payment_hash",
 			     &hin->payment_hash, sizeof(hin->payment_hash));
@@ -471,7 +473,9 @@ static void json_add_htlcs(struct lightningd *ld,
 		json_object_start(response, NULL);
 		json_add_string(response, "direction", "out");
 		json_add_u64(response, "id", hout->key.id);
-		json_add_u64(response, "msatoshi", hout->msatoshi);
+		json_add_amount_msat(response,
+				     (struct amount_msat){ hout->msatoshi },
+				     "msatoshi", "amount_msat");
 		json_add_u64(response, "expiry", hout->cltv_expiry);
 		json_add_hex(response, "payment_hash",
 			     &hout->payment_hash, sizeof(hout->payment_hash));

plugins/pay.c

@@ -404,7 +404,7 @@ static struct command_result *getroute_done(struct command *cmd,
 	struct pay_attempt *attempt = current_attempt(pc);
 	const jsmntok_t *t = json_get_member(buf, result, "route");
 	char *json_desc;
-	u64 fee;
+	struct amount_msat fee;
 	u32 delay;
 	double feepercent;
 
@@ -418,32 +418,36 @@ static struct command_result *getroute_done(struct command *cmd,
 	else
 		attempt->route = json_strdup(pc->ps->attempts, buf, t);
 
-	if (!json_to_u64(buf, json_delve(buf, t, "[0].msatoshi"), &fee))
-		plugin_err("getroute with invalid msatoshi? '%.*s'",
+	if (!json_to_msat(buf, json_delve(buf, t, "[0].msatoshi"), &fee))
+		plugin_err("getroute with invalid msatoshi? %.*s",
 			   result->end - result->start, buf);
-	fee -= pc->msatoshi;
+	fee.millisatoshis -= pc->msatoshi;
 
 	if (!json_to_number(buf, json_delve(buf, t, "[0].delay"), &delay))
-		plugin_err("getroute with invalid delay? '%.*s'",
+		plugin_err("getroute with invalid delay? %.*s",
 			   result->end - result->start, buf);
 
 	/* Casting u64 to double will lose some precision. The loss of precision
 	 * in feepercent will be like 3.0000..(some dots)..1 % - 3.0 %.
 	 * That loss will not be representable in double. So, it's Okay to
 	 * cast u64 to double for feepercent calculation. */
-	feepercent = ((double)fee) * 100.0 / ((double) pc->msatoshi);
+	feepercent = ((double)fee.millisatoshis) * 100.0 / ((double) pc->msatoshi);
 
-	if (fee > pc->exemptfee && feepercent > pc->maxfeepercent) {
+	if (fee.millisatoshis > pc->exemptfee && feepercent > pc->maxfeepercent) {
 		const jsmntok_t *charger;
 
-		attempt_failed_fmt(pc, "{ 'message': 'Route wanted fee of %"PRIu64" msatoshis' }", fee);
+		attempt_failed_fmt(pc, "{ 'message': 'Route wanted fee of %s' }",
+				   type_to_string(tmpctx, struct amount_msat,
+						  &fee));
 
 		/* Remember this if we eliminating this causes us to have no
 		 * routes at all! */
 		if (!pc->expensive_route)
 			pc->expensive_route
-				= tal_fmt(pc, "Route wanted fee of %"PRIu64
-					  " msatoshis", fee);
+				= tal_fmt(pc, "Route wanted fee of %s",
+					  type_to_string(tmpctx,
+							 struct amount_msat,
+							 &fee));
 
 		/* Try excluding most fee-charging channel (unless it's in
 		 * routeboost). */
@@ -817,7 +821,7 @@ static struct command_result *handle_pay(struct command *cmd,
 					 const char *buf,
 					 const jsmntok_t *params)
 {
-	u64 *msatoshi;
+	struct amount_msat *msat;
 	struct bolt11 *b11;
 	const char *b11str;
 	char *fail;
@@ -832,7 +836,7 @@ static struct command_result *handle_pay(struct command *cmd,
 
 	if (!param(cmd, buf, params,
 		   p_req("bolt11", param_string, &b11str),
-		   p_opt("msatoshi", param_u64, &msatoshi),
+		   p_opt("msatoshi", param_msat, &msat),
 		   p_opt("description", param_string, &pc->desc),
 		   p_opt_def("riskfactor", param_double, &riskfactor, 10),
 		   p_opt_def("maxfeepercent", param_percent, &maxfeepercent, 0.5),
@@ -854,17 +858,17 @@ static struct command_result *handle_pay(struct command *cmd,
 	}
 
 	if (b11->msat) {
-		if (msatoshi) {
+		if (msat) {
 			return command_fail(cmd, JSONRPC2_INVALID_PARAMS,
 					    "msatoshi parameter unnecessary");
 		}
 		pc->msatoshi = b11->msat->millisatoshis;
 	} else {
-		if (!msatoshi) {
+		if (!msat) {
 			return command_fail(cmd, JSONRPC2_INVALID_PARAMS,
 					    "msatoshi parameter required");
 		}
-		pc->msatoshi = *msatoshi;
+		pc->msatoshi = msat->millisatoshis;
 	}
 
 	pc->maxfeepercent = *maxfeepercent;

tests/test_pay.py

@@ -69,7 +69,7 @@ def test_pay_limits(node_factory):
     inv = l3.rpc.invoice("any", "any", 'description')
 
     # Fee too high.
-    with pytest.raises(RpcError, match=r'Route wanted fee of .* msatoshis') as err:
+    with pytest.raises(RpcError, match=r'Route wanted fee of .*msat') as err:
         l1.rpc.call('pay', {'bolt11': inv['bolt11'], 'msatoshi': 100000, 'maxfeepercent': 0.0001, 'exemptfee': 0})
 
     assert err.value.error['code'] == PAY_ROUTE_TOO_EXPENSIVE
@@ -1016,8 +1016,10 @@ def test_forward_pad_fees_and_cltv(node_factory, bitcoind):
 
     # Modify so we overpay, overdo the cltv.
     route[0]['msatoshi'] += 2000
+    route[0]['amount_msat'] = str(route[0]['msatoshi']) + 'msat'
     route[0]['delay'] += 20
     route[1]['msatoshi'] += 1000
+    route[1]['amount_msat'] = str(route[1]['msatoshi']) + 'msat'
     route[1]['delay'] += 10
 
     # This should work.

wallet/test/run-wallet.c

@@ -199,6 +199,13 @@ void json_add_address_internal(struct json_stream *response UNNEEDED,
 			       const char *fieldname UNNEEDED,
 			       const struct wireaddr_internal *addr UNNEEDED)
 { fprintf(stderr, "json_add_address_internal called!\n"); abort(); }
+/* Generated stub for json_add_amount_msat */
+void json_add_amount_msat(struct json_stream *result UNNEEDED,
+			  struct amount_msat msat UNNEEDED,
+			  const char *rawfieldname UNNEEDED,
+			  const char *msatfieldname)
+
+{ fprintf(stderr, "json_add_amount_msat called!\n"); abort(); }
 /* Generated stub for json_add_bool */
 void json_add_bool(struct json_stream *result UNNEEDED, const char *fieldname UNNEEDED,
 		   bool value UNNEEDED)