channeld: map htlc add/remove errors to names.

I couldn't figure out what 'Bad peer_add_htlc: 7' meant!

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

channeld/Makefile

@@ -8,21 +8,22 @@ default: channeld-all
 
 channeld-all: lightningd/lightning_channeld
 
-# lightningd/channel needs these:
 LIGHTNINGD_CHANNEL_HEADERS_GEN :=			\
+	channeld/gen_full_channel_error_names.h		\
 	channeld/gen_channel_wire.h
 
 LIGHTNINGD_CHANNEL_HEADERS_NOGEN :=			\
 	channeld/channeld_htlc.h		\
 	channeld/commit_tx.h			\
-	channeld/full_channel.h
+	channeld/full_channel.h			\
+	channeld/full_channel_error.h
 
 LIGHTNINGD_CHANNEL_HEADERS := $(LIGHTNINGD_CHANNEL_HEADERS_GEN) $(LIGHTNINGD_CHANNEL_HEADERS_NOGEN)
 
 LIGHTNINGD_CHANNEL_SRC := channeld/channel.c	\
 	channeld/commit_tx.c			\
 	channeld/full_channel.c		\
-	$(LIGHTNINGD_CHANNEL_HEADERS_GEN:.h=.c)
+	channeld/gen_channel_wire.c
 LIGHTNINGD_CHANNEL_OBJS := $(LIGHTNINGD_CHANNEL_SRC:.c=.o)
 
 # Make sure these depend on everything.
@@ -72,19 +73,23 @@ CHANNELD_COMMON_OBJS :=				\
 	wire/fromwire.o				\
 	wire/towire.o
 
+LIGHTNINGD_CHANNEL_SRC_GEN := $(filter channeld/gen_%, $(LIGHTNINGD_CHANNEL_SRC))
+
+LIGHTNINGD_CHANNEL_SRC_NOGEN := $(filter-out channeld/gen_%, $(LIGHTNINGD_CHANNEL_SRC))
+
 # Control daemon uses this:
 LIGHTNINGD_CHANNEL_CONTROL_HEADERS := $(LIGHTNINGD_CHANNEL_HEADERS_GEN)
-LIGHTNINGD_CHANNEL_CONTROL_SRC := $(LIGHTNINGD_CHANNEL_HEADERS_GEN:.h=.c)
+LIGHTNINGD_CHANNEL_CONTROL_SRC := $(LIGHTNINGD_CHANNEL_SRC_GEN)
 LIGHTNINGD_CHANNEL_CONTROL_OBJS := $(LIGHTNINGD_CHANNEL_CONTROL_SRC:.c=.o)
 
-LIGHTNINGD_CHANNEL_GEN_SRC := $(filter channeld/gen_%, $(LIGHTNINGD_CHANNEL_SRC) $(LIGHTNINGD_CHANNEL_CONTROL_SRC))
-
-LIGHTNINGD_CHANNEL_SRC_NOGEN := $(filter-out channeld/gen_%, $(LIGHTNINGD_CHANNEL_SRC))
-
 # Add to headers which any object might need.
 LIGHTNINGD_HEADERS_GEN += $(LIGHTNINGD_CHANNEL_HEADERS_GEN)
 LIGHTNINGD_HEADERS_NOGEN += $(LIGHTNINGD_CHANNEL_HEADERS_NOGEN)
 
+channeld/gen_full_channel_error_names.h: channeld/full_channel_error.h ccan/ccan/cdump/tools/cdump-enumstr
+	ccan/ccan/cdump/tools/cdump-enumstr channeld/full_channel_error.h > $@
+
+
 $(LIGHTNINGD_CHANNEL_OBJS): $(LIGHTNINGD_HEADERS)
 
 channeld/gen_channel_wire.h: $(WIRE_GEN) channeld/channel_wire.csv
@@ -93,7 +98,7 @@ channeld/gen_channel_wire.h: $(WIRE_GEN) channeld/channel_wire.csv
 channeld/gen_channel_wire.c: $(WIRE_GEN) channeld/channel_wire.csv
 	$(WIRE_GEN) ${@:.c=.h} channel_wire_type < channeld/channel_wire.csv > $@
 
-LIGHTNINGD_CHANNEL_OBJS := $(LIGHTNINGD_CHANNEL_SRC:.c=.o) $(LIGHTNINGD_CHANNEL_GEN_SRC:.c=.o)
+LIGHTNINGD_CHANNEL_OBJS := $(LIGHTNINGD_CHANNEL_SRC:.c=.o)
 
 lightningd/lightning_channeld: $(LIGHTNINGD_CHANNEL_OBJS) $(WIRE_ONION_OBJS) $(CHANNELD_COMMON_OBJS) $(WIRE_OBJS) $(BITCOIN_OBJS) $(LIGHTNINGD_HSM_CLIENT_OBJS)
 

channeld/channel.c

@@ -596,7 +596,8 @@ static void handle_peer_add_htlc(struct peer *peer, const u8 *msg)
 		peer_failed(PEER_FD,
 			    &peer->cs,
 			    &peer->channel_id,
-			    "Bad peer_add_htlc: %u", add_err);
+			    "Bad peer_add_htlc: %s",
+			    channel_add_err_name(add_err));
 
 	/* If this is wrong, we don't complain yet; when it's confirmed we'll
 	 * send it to the master which handles all HTLC failures. */
@@ -1389,7 +1390,7 @@ static void handle_peer_fulfill_htlc(struct peer *peer, const u8 *msg)
 			    &peer->cs,
 			    &peer->channel_id,
 			    "Bad update_fulfill_htlc: failed to fulfill %"
-			    PRIu64 " error %u", id, e);
+			    PRIu64 " error %s", id, channel_remove_err_name(e));
 	}
 	abort();
 }
@@ -1427,7 +1428,8 @@ static void handle_peer_fail_htlc(struct peer *peer, const u8 *msg)
 			    &peer->cs,
 			    &peer->channel_id,
 			    "Bad update_fail_htlc: failed to remove %"
-			    PRIu64 " error %u", id, e);
+			    PRIu64 " error %s", id,
+			    channel_remove_err_name(e));
 	}
 	abort();
 }
@@ -1500,7 +1502,7 @@ static void handle_peer_fail_malformed_htlc(struct peer *peer, const u8 *msg)
 			    &peer->cs,
 			    &peer->channel_id,
 			    "Bad update_fail_malformed_htlc: failed to remove %"
-			    PRIu64 " error %u", id, e);
+			    PRIu64 " error %s", id, channel_remove_err_name(e));
 	}
 	abort();
 }
@@ -2004,8 +2006,9 @@ static void handle_offer_htlc(struct peer *peer, const u8 *inmsg)
 	e = channel_add_htlc(peer->channel, LOCAL, peer->htlc_id,
 			     amount_msat, cltv_expiry, &payment_hash,
 			     onion_routing_packet, NULL);
-	status_trace("Adding HTLC %"PRIu64" msat=%"PRIu64" cltv=%u gave %i",
+	status_trace("Adding HTLC %"PRIu64" msat=%"PRIu64" cltv=%u gave %s",
-		     peer->htlc_id, amount_msat, cltv_expiry, e);
+		     peer->htlc_id, amount_msat, cltv_expiry,
+		     channel_add_err_name(e));
 
 	switch (e) {
 	case CHANNEL_ERR_ADD_OK:
@@ -2284,7 +2287,8 @@ static void handle_fail(struct peer *peer, const u8 *inmsg)
 	case CHANNEL_ERR_HTLC_NOT_IRREVOCABLE:
 	case CHANNEL_ERR_BAD_PREIMAGE:
 		status_failed(STATUS_FAIL_MASTER_IO,
-			      "HTLC %"PRIu64" removal failed: %i", id, e);
+			      "HTLC %"PRIu64" removal failed: %s", id,
+			      channel_remove_err_name(e));
 	}
 	abort();
 }

channeld/full_channel.c

@@ -17,7 +17,10 @@
 #include <common/status.h>
 #include <common/type_to_string.h>
 #include <inttypes.h>
+#include <stdio.h>
 #include <string.h>
+  /* Needs to be at end, since it doesn't include its own hdrs */
+  #include "gen_full_channel_error_names.h"
 
 struct channel *new_full_channel(const tal_t *ctx,
 				 const struct bitcoin_txid *funding_txid,
@@ -1055,3 +1058,27 @@ bool channel_force_htlcs(struct channel *channel,
 
 	return true;
 }
+
+const char *channel_add_err_name(enum channel_add_err e)
+{
+	static char invalidbuf[sizeof("INVALID ") + STR_MAX_CHARS(e)];
+
+	for (size_t i = 0; enum_channel_add_err_names[i].name; i++) {
+		if (enum_channel_add_err_names[i].v == e)
+			return enum_channel_add_err_names[i].name;
+	}
+	sprintf(invalidbuf, "INVALID %i", e);
+	return invalidbuf;
+}
+
+const char *channel_remove_err_name(enum channel_remove_err e)
+{
+	static char invalidbuf[sizeof("INVALID ") + STR_MAX_CHARS(e)];
+
+	for (size_t i = 0; enum_channel_remove_err_names[i].name; i++) {
+		if (enum_channel_remove_err_names[i].v == e)
+			return enum_channel_remove_err_names[i].name;
+	}
+	sprintf(invalidbuf, "INVALID %i", e);
+	return invalidbuf;
+}

channeld/full_channel.h

@@ -3,6 +3,7 @@
 #define LIGHTNING_LIGHTNINGD_CHANNEL_FULL_CHANNEL_H
 #include "config.h"
 #include <channeld/channeld_htlc.h>
+#include <channeld/full_channel_error.h>
 #include <common/initial_channel.h>
 #include <common/sphinx.h>
 
@@ -77,25 +78,6 @@ struct bitcoin_tx **channel_txs(const tal_t *ctx,
 u32 actual_feerate(const struct channel *channel,
 		   const struct signature *theirsig);
 
-enum channel_add_err {
-	/* All OK! */
-	CHANNEL_ERR_ADD_OK,
-	/* Bad expiry value */
-	CHANNEL_ERR_INVALID_EXPIRY,
-	/* Not really a failure, if expected: it's an exact duplicate. */
-	CHANNEL_ERR_DUPLICATE,
-	/* Same ID, but otherwise different. */
-	CHANNEL_ERR_DUPLICATE_ID_DIFFERENT,
-	/* Would exceed the specified max_htlc_value_in_flight_msat */
-	CHANNEL_ERR_MAX_HTLC_VALUE_EXCEEDED,
-	/* Can't afford it */
-	CHANNEL_ERR_CHANNEL_CAPACITY_EXCEEDED,
-	/* HTLC is below htlc_minimum_msat */
-	CHANNEL_ERR_HTLC_BELOW_MINIMUM,
-	/* HTLC would push past max_accepted_htlcs */
-	CHANNEL_ERR_TOO_MANY_HTLCS,
-};
-
 /**
  * channel_add_htlc: append an HTLC to channel if it can afford it
  * @channel: The channel
@@ -128,21 +110,6 @@ enum channel_add_err channel_add_htlc(struct channel *channel,
  */
 struct htlc *channel_get_htlc(struct channel *channel, enum side sender, u64 id);
 
-enum channel_remove_err {
-	/* All OK! */
-	CHANNEL_ERR_REMOVE_OK,
-	/* No such HTLC. */
-	CHANNEL_ERR_NO_SUCH_ID,
-	/* Already have fulfilled it */
-	CHANNEL_ERR_ALREADY_FULFILLED,
-	/* Preimage doesn't hash to value. */
-	CHANNEL_ERR_BAD_PREIMAGE,
-	/* HTLC is not committed */
-	CHANNEL_ERR_HTLC_UNCOMMITTED,
-	/* HTLC is not committed and prior revoked on both sides */
-	CHANNEL_ERR_HTLC_NOT_IRREVOCABLE
-};
-
 /**
  * channel_fail_htlc: remove an HTLC, funds to the side which offered it.
  * @channel: The channel state
@@ -279,4 +246,8 @@ bool channel_force_htlcs(struct channel *channel,
  * Uses status_trace() on every HTLC.
  */
 void dump_htlcs(const struct channel *channel, const char *prefix);
+
+const char *channel_add_err_name(enum channel_add_err e);
+const char *channel_remove_err_name(enum channel_remove_err e);
+
 #endif /* LIGHTNING_LIGHTNINGD_CHANNEL_FULL_CHANNEL_H */

channeld/full_channel_error.h

@@ -0,0 +1,39 @@
+/* Error enums separated out for easy autogen of names*/
+#ifndef LIGHTNING_CHANNELD_FULL_CHANNEL_ERROR_H
+#define LIGHTNING_CHANNELD_FULL_CHANNEL_ERROR_H
+
+enum channel_add_err {
+	/* All OK! */
+	CHANNEL_ERR_ADD_OK,
+	/* Bad expiry value */
+	CHANNEL_ERR_INVALID_EXPIRY,
+	/* Not really a failure, if expected: it's an exact duplicate. */
+	CHANNEL_ERR_DUPLICATE,
+	/* Same ID, but otherwise different. */
+	CHANNEL_ERR_DUPLICATE_ID_DIFFERENT,
+	/* Would exceed the specified max_htlc_value_in_flight_msat */
+	CHANNEL_ERR_MAX_HTLC_VALUE_EXCEEDED,
+	/* Can't afford it */
+	CHANNEL_ERR_CHANNEL_CAPACITY_EXCEEDED,
+	/* HTLC is below htlc_minimum_msat */
+	CHANNEL_ERR_HTLC_BELOW_MINIMUM,
+	/* HTLC would push past max_accepted_htlcs */
+	CHANNEL_ERR_TOO_MANY_HTLCS,
+};
+
+enum channel_remove_err {
+	/* All OK! */
+	CHANNEL_ERR_REMOVE_OK,
+	/* No such HTLC. */
+	CHANNEL_ERR_NO_SUCH_ID,
+	/* Already have fulfilled it */
+	CHANNEL_ERR_ALREADY_FULFILLED,
+	/* Preimage doesn't hash to value. */
+	CHANNEL_ERR_BAD_PREIMAGE,
+	/* HTLC is not committed */
+	CHANNEL_ERR_HTLC_UNCOMMITTED,
+	/* HTLC is not committed and prior revoked on both sides */
+	CHANNEL_ERR_HTLC_NOT_IRREVOCABLE
+};
+
+#endif /* LIGHTNING_CHANNELD_FULL_CHANNEL_ERROR_H */

tests/test_lightningd.py

@@ -2065,9 +2065,9 @@ class LightningDTests(BaseLightningDTests):
 
         # We add one to the blockcount for a bit of fuzz (FIXME: Shadowroute would fix this!)
         shadow_route = 1
-        l1.daemon.wait_for_log("Adding HTLC 0 msat=5010198 cltv={} gave 0"
+        l1.daemon.wait_for_log("Adding HTLC 0 msat=5010198 cltv={} gave CHANNEL_ERR_ADD_OK"
                                .format(bitcoind.rpc.getblockcount() + 20 + 9 + shadow_route))
-        l2.daemon.wait_for_log("Adding HTLC 0 msat=4999999 cltv={} gave 0"
+        l2.daemon.wait_for_log("Adding HTLC 0 msat=4999999 cltv={} gave CHANNEL_ERR_ADD_OK"
                                .format(bitcoind.rpc.getblockcount() + 9 + shadow_route))
         l3.daemon.wait_for_log("test_forward_different_fees_and_cltv: Actual amount 4999999msat, HTLC expiry {}"
                                .format(bitcoind.rpc.getblockcount() + 9 + shadow_route))