From feb92cf4e2e31cbacb4e5d1744efb0b2a107b4ec Mon Sep 17 00:00:00 2001
From: Rusty Russell <rusty@rustcorp.com.au>
Date: Thu, 21 Feb 2019 13:08:51 +1030
Subject: [PATCH] sendpay: allow 'amount_msat'

We're about to add 'amount_msat' to getroute, but it's common to feed
'getroute' back into 'sendpay', so sendpay should allow it.

If both are specified, make sure they're the same!

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
---
 lightningd/pay.c | 36 ++++++++++++++++++++++++++++++------
 1 file changed, 30 insertions(+), 6 deletions(-)

diff --git a/lightningd/pay.c b/lightningd/pay.c
index d06f2224d..3f58a0cb8 100644
--- a/lightningd/pay.c
+++ b/lightningd/pay.c
@@ -754,21 +754,45 @@ static struct command_result *json_sendpay(struct command *cmd,
 
 	route = tal_arr(cmd, struct route_hop, routetok->size);
 	json_for_each_arr(i, t, routetok) {
-		u64 *amount;
+		struct amount_msat *msat, *amount_msat;
 		struct pubkey *id;
 		struct short_channel_id *channel;
 		unsigned *delay, *direction;
 
 		if (!param(cmd, buffer, t,
-			   p_req("msatoshi", param_u64, &amount),
-			   p_req("id", param_pubkey, &id),
-			   p_req("delay", param_number, &delay),
-			   p_req("channel", param_short_channel_id, &channel),
+			   /* Only *one* of these is required */
+			   p_opt("msatoshi", param_msat, &msat),
+			   p_opt("amount_msat", param_msat, &amount_msat),
+			   /* These three actually required */
+			   p_opt("id", param_pubkey, &id),
+			   p_opt("delay", param_number, &delay),
+			   p_opt("channel", param_short_channel_id, &channel),
 			   p_opt("direction", param_number, &direction),
 			   NULL))
 			return command_param_failed();
 
-		route[i].amount = *amount;
+		if (!msat && !amount_msat)
+			return command_fail(cmd, JSONRPC2_INVALID_PARAMS,
+					    "route[%zi]: must have msatoshi"
+					    " or amount_msat", i);
+		if (!id || !channel || !delay)
+			return command_fail(cmd, JSONRPC2_INVALID_PARAMS,
+					    "route[%zi]: must have id, channel"
+					    " and delay", i);
+		if (msat && amount_msat && !amount_msat_eq(*msat, *amount_msat))
+			return command_fail(cmd, JSONRPC2_INVALID_PARAMS,
+					    "route[%zi]: msatoshi %s != amount_msat %s",
+					    i,
+					    type_to_string(tmpctx,
+							   struct amount_msat,
+							   msat),
+					    type_to_string(tmpctx,
+							   struct amount_msat,
+							   amount_msat));
+		if (!msat)
+			msat = amount_msat;
+
+		route[i].amount = msat->millisatoshis;
 		route[i].nodeid = *id;
 		route[i].delay = *delay;
 		route[i].channel_id = *channel;