lightningd: move cmd pointer from struct pay_command directly into ht…

…lc_out.

Set if a command is responsible.

Signed-off-by: Rusty Russell <[email protected]>

lightningd/htlc_end.c

@@ -127,6 +127,8 @@ struct htlc_out *htlc_out_check(const struct htlc_out *hout,
 			       htlc_state_name(hout->hstate));
 	else if (hout->failuremsg && hout->preimage)
 		return corrupt(hout, abortstr, "Both failed and succeeded");
+	else if (hout->cmd && hout->in)
+		return corrupt(hout, abortstr, "Both local and forwarded");
 	else if (!hout->in && !hout->pay_command)
 		return corrupt(hout, abortstr,
 			       "Neither hout->in nor paycommand");
@@ -142,7 +144,8 @@ struct htlc_out *new_htlc_out(const tal_t *ctx,
 			      const u8 *onion_routing_packet,
 			      struct htlc_in *in,
 			      struct pay_command *pc,
-			      struct wallet_payment *payment)
+			      struct wallet_payment *payment,
+			      struct command *cmd)
 {
 	struct htlc_out *hout = tal(ctx, struct htlc_out);
 
@@ -155,6 +158,7 @@ struct htlc_out *new_htlc_out(const tal_t *ctx,
 	hout->cltv_expiry = cltv_expiry;
 	hout->payment_hash = *payment_hash;
 	hout->payment = tal_steal(hout, payment);
+	hout->cmd = cmd;
 	memcpy(hout->onion_routing_packet, onion_routing_packet,
 	       sizeof(hout->onion_routing_packet));
 

lightningd/htlc_end.h

@@ -76,6 +76,9 @@ struct htlc_out {
 	/* Where it's from, if not going to us. */
 	struct htlc_in *in;
 
+	/* Otherwise, this MAY be non-null if there's a pay command waiting */
+	struct command *cmd;
+
 	/* Otherwise, payment command which created it. */
 	struct pay_command *pay_command;
 
@@ -137,7 +140,8 @@ struct htlc_out *new_htlc_out(const tal_t *ctx,
 			      const u8 *onion_routing_packet,
 			      struct htlc_in *in,
 			      struct pay_command *pc,
-			      struct wallet_payment *payment);
+			      struct wallet_payment *payment,
+			      struct command *cmd);
 
 void connect_htlc_in(struct htlc_in_map *map, struct htlc_in *hin);
 void connect_htlc_out(struct htlc_out_map *map, struct htlc_out *hout);

lightningd/pay.c

@@ -27,7 +27,6 @@ struct pay_command {
 	struct htlc_out *out;
 	/* Preimage if this succeeded. */
 	const struct preimage *rval;
-	struct command *cmd;
 };
 
 static void json_pay_success(struct command *cmd, const struct preimage *rval)
@@ -45,20 +44,17 @@ static void json_pay_success(struct command *cmd, const struct preimage *rval)
 	command_success(cmd, response);
 }
 
-static void json_pay_failed(struct pay_command *pc,
+static void json_pay_failed(struct command *cmd,
 			    const struct pubkey *sender,
 			    enum onion_type failure_code,
 			    const char *details)
 {
 	/* Can be NULL if JSON RPC goes away. */
-	if (!pc->cmd)
-		return;
-
-	/* FIXME: Report sender! */
-	command_fail(pc->cmd, "failed: %s (%s)",
-		     onion_type_name(failure_code), details);
-
-	pc->out = NULL;
+	if (cmd) {
+		/* FIXME: Report sender! */
+		command_fail(cmd, "failed: %s (%s)",
+			     onion_type_name(failure_code), details);
+	}
 }
 
 void payment_succeeded(struct lightningd *ld, struct htlc_out *hout,
@@ -69,7 +65,9 @@ void payment_succeeded(struct lightningd *ld, struct htlc_out *hout,
 				  PAYMENT_COMPLETE, rval);
 	hout->pay_command->rval = tal_dup(hout->pay_command,
 					  struct preimage, rval);
-	json_pay_success(hout->pay_command->cmd, rval);
+	/* Can be NULL if JSON RPC goes away. */
+	if (hout->cmd)
+		json_pay_success(hout->cmd, rval);
 	hout->pay_command->out = NULL;
 }
 
@@ -84,10 +82,11 @@ void payment_failed(struct lightningd *ld, const struct htlc_out *hout,
 
 	wallet_payment_set_status(ld->wallet, &hout->payment_hash,
 				  PAYMENT_FAILED, NULL);
+	pc->out = NULL;
 
 	/* This gives more details than a generic failure message */
 	if (localfail) {
-		json_pay_failed(pc, NULL, hout->failcode, localfail);
+		json_pay_failed(hout->cmd, NULL, hout->failcode, localfail);
 		tal_free(tmpctx);
 		return;
 	}
@@ -118,17 +117,15 @@ void payment_failed(struct lightningd *ld, const struct htlc_out *hout,
 	/* FIXME: check for routing failure / perm fail. */
 	/* check_for_routing_failure(i, sender, failure_code); */
 
-	json_pay_failed(pc, NULL, failcode, "reply from remote");
+	json_pay_failed(hout->cmd, NULL, failcode, "reply from remote");
 	tal_free(tmpctx);
 }
 
-/* When JSON RPC goes away, cmd is freed: detach from any running paycommand */
-static void remove_cmd_from_pc(struct command *cmd, struct pay_command *pc)
+/* When JSON RPC goes away, cmd is freed: detach from the hout */
+static void remove_cmd_from_hout(struct command *cmd, struct htlc_out *hout)
 {
-	/* This can be false, in the case where another pay command
-	 * re-uses the pc->cmd before we get around to cleaning up. */
-	if (pc->cmd == cmd)
-		pc->cmd = NULL;
+	assert(hout->cmd == cmd);
+	hout->cmd = NULL;
 }
 
 static struct pay_command *find_pay_command(struct lightningd *ld,
@@ -254,7 +251,6 @@ static bool send_payment(struct command *cmd,
 		payment->payment_preimage = NULL;
 		payment->path_secrets = tal_steal(payment, path_secrets);
 	}
-	pc->cmd = cmd;
 	pc->rhash = *rhash;
 	pc->rval = NULL;
 	pc->ids = tal_steal(pc, ids);
@@ -264,23 +260,24 @@ static bool send_payment(struct command *cmd,
 	log_info(cmd->ld->log, "Sending %u over %zu hops to deliver %"PRIu64,
 		 route[0].amount, n_hops, pc->msatoshi);
 
-	/* Wait until we get response. */
-	tal_add_destructor2(cmd, remove_cmd_from_pc, pc);
-
 	/* They're both children of ld, but on shutdown make sure we
 	 * destroy the command before the pc, otherwise the
 	 * remove_cmd_from_pc destructor causes a use-after-free */
 	tal_steal(pc, cmd);
 
 	failcode = send_htlc_out(peer, route[0].amount,
 				 base_expiry + route[0].delay,
-				 rhash, onion, NULL, payment, pc,
+				 rhash, onion, NULL, payment, pc, cmd,
 				 &pc->out);
 	if (failcode) {
 		command_fail(cmd, "first peer not ready: %s",
 			     onion_type_name(failcode));
 		return false;
 	}
+
+	/* If we fail, remove cmd ptr from htlc_out. */
+	tal_add_destructor2(cmd, remove_cmd_from_hout, pc->out);
+
 	tal_free(tmpctx);
 	return true;
 }

lightningd/peer_htlcs.c

@@ -374,6 +374,7 @@ enum onion_type send_htlc_out(struct peer *out, u64 amount, u32 cltv,
 			      struct htlc_in *in,
 			      struct wallet_payment *payment,
 			      struct pay_command *pc,
+			      struct command *cmd,
 			      struct htlc_out **houtp)
 {
 	struct htlc_out *hout;
@@ -394,7 +395,7 @@ enum onion_type send_htlc_out(struct peer *out, u64 amount, u32 cltv,
 	/* Make peer's daemon own it, catch if it dies. */
 	hout = new_htlc_out(out->owner, out, amount, cltv,
 			    payment_hash, onion_routing_packet, in,
-			    pc, payment);
+			    pc, payment, cmd);
 	tal_add_destructor(hout, hout_subd_died);
 
 	msg = towire_channel_offer_htlc(out, amount, cltv, payment_hash,
@@ -486,7 +487,7 @@ static void forward_htlc(struct htlc_in *hin,
 
 	failcode = send_htlc_out(next, amt_to_forward,
 				 outgoing_cltv_value, &hin->payment_hash,
-				 next_onion, hin, NULL, NULL, NULL);
+				 next_onion, hin, NULL, NULL, NULL, NULL);
 	if (!failcode)
 		return;
 

lightningd/peer_htlcs.h

@@ -41,6 +41,7 @@ enum onion_type send_htlc_out(struct peer *out, u64 amount, u32 cltv,
 			      struct htlc_in *in,
 			      struct wallet_payment *payment,
 			      struct pay_command *pc,
+			      struct command *cmd,
 			      struct htlc_out **houtp);
 
 struct htlc_out *find_htlc_out_by_ripemd(const struct peer *peer,

wallet/wallet.c

@@ -1050,6 +1050,7 @@ static bool wallet_stmt2htlc_out(const struct wallet_channel *channel,
 
 	out->failuremsg = NULL;
 	out->failcode = 0;
+	out->cmd = NULL;
 
 	/* Need to defer wiring until we can look up all incoming
 	 * htlcs, will wire using origin_htlc_id */