From 540c68d7cad4ca8295e97e52576f64e13d7a26d0 Mon Sep 17 00:00:00 2001
From: Rusty Russell <rusty@rustcorp.com.au>
Date: Thu, 17 May 2018 14:38:11 +0930
Subject: [PATCH] gossipd/gossip_constants.h: Single place for BOLT constants.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
---
 channeld/Makefile            |  2 +-
 channeld/channel.c           |  2 +-
 gossipd/Makefile             |  4 ++--
 gossipd/gossip_constants.h   | 33 +++++++++++++++++++++++++++++++++
 gossipd/routing.h            | 12 +-----------
 lightningd/channel_control.c |  1 +
 lightningd/peer_control.h    |  2 --
 7 files changed, 39 insertions(+), 17 deletions(-)
 create mode 100644 gossipd/gossip_constants.h

diff --git a/channeld/Makefile b/channeld/Makefile
index 7769e638f..c63071534 100644
--- a/channeld/Makefile
+++ b/channeld/Makefile
@@ -93,7 +93,7 @@ channeld/gen_full_channel_error_names.h: channeld/full_channel_error.h ccan/ccan
 	ccan/ccan/cdump/tools/cdump-enumstr channeld/full_channel_error.h > $@
 
 
-$(LIGHTNINGD_CHANNEL_OBJS): $(LIGHTNINGD_HEADERS)
+$(LIGHTNINGD_CHANNEL_OBJS): $(LIGHTNINGD_HEADERS) $(LIGHTNINGD_GOSSIP_CONTROL_HEADERS)
 
 channeld/gen_channel_wire.h: $(WIRE_GEN) channeld/channel_wire.csv
 	$(WIRE_GEN) --header $@ channel_wire_type < channeld/channel_wire.csv > $@
diff --git a/channeld/channel.c b/channeld/channel.c
index e6e2ae90f..3da6b0b79 100644
--- a/channeld/channel.c
+++ b/channeld/channel.c
@@ -46,7 +46,7 @@
 #include <errno.h>
 #include <fcntl.h>
 #include <gossipd/gen_gossip_wire.h>
-#include <gossipd/routing.h>
+#include <gossipd/gossip_constants.h>
 #include <hsmd/gen_hsm_client_wire.h>
 #include <inttypes.h>
 #include <secp256k1.h>
diff --git a/gossipd/Makefile b/gossipd/Makefile
index 8f44fc7f2..cabbab3b1 100644
--- a/gossipd/Makefile
+++ b/gossipd/Makefile
@@ -7,7 +7,7 @@ gossipd-wrongdir:
 default: gossipd-all
 
 # Control daemon uses this:
-LIGHTNINGD_GOSSIP_CONTROL_HEADERS := gossipd/gen_gossip_wire.h
+LIGHTNINGD_GOSSIP_CONTROL_HEADERS := gossipd/gen_gossip_wire.h gossipd/gossip_constants.h
 LIGHTNINGD_GOSSIP_CONTROL_SRC := gossipd/gen_gossip_wire.c
 LIGHTNINGD_GOSSIP_CONTROL_OBJS := $(LIGHTNINGD_GOSSIP_CONTROL_SRC:.c=.o)
 
@@ -28,7 +28,7 @@ LIGHTNINGD_GOSSIP_OBJS := $(LIGHTNINGD_GOSSIP_SRC:.c=.o)
 # Make sure these depend on everything.
 ALL_OBJS += $(LIGHTNINGD_GOSSIP_OBJS)
 ALL_PROGRAMS += lightningd/lightning_gossipd
-ALL_GEN_HEADERS += $(LIGHTNINGD_GOSSIP_CONTROL_HEADERS)
+ALL_GEN_HEADERS += gossipd/gen_gossip_wire.h
 
 # For checking
 LIGHTNINGD_GOSSIP_ALLSRC_NOGEN := $(filter-out gossipd/gen_%, $(LIGHTNINGD_GOSSIP_CLIENT_SRC) $(LIGHTNINGD_GOSSIP_SRC))
diff --git a/gossipd/gossip_constants.h b/gossipd/gossip_constants.h
new file mode 100644
index 000000000..4b1e0c040
--- /dev/null
+++ b/gossipd/gossip_constants.h
@@ -0,0 +1,33 @@
+#ifndef LIGHTNING_GOSSIPD_GOSSIP_CONSTANTS_H
+#define LIGHTNING_GOSSIPD_GOSSIP_CONSTANTS_H
+
+/* BOLT #4:
+ *
+ * - Length: the maximum route length is limited to 20 hops.
+ *...
+ * 1. type: `onion_packet`
+ * 2. data:
+ *    * [`1`:`version`]
+ *    * [`33`:`public_key`]
+ *    * [`20*65`:`hops_data`]
+ */
+#define ROUTING_MAX_HOPS 20
+
+/* BOLT #7:
+ *
+ * The `flags` bitfield...individual bits:
+ *...
+ * | 0             | `direction` | Direction this update refers to. |
+ * | 1             | `disable`   | Disable the channel.             |
+ */
+#define ROUTING_FLAGS_DIRECTION (1 << 0)
+#define ROUTING_FLAGS_DISABLED  (1 << 1)
+
+/* BOLT #7:
+ *
+ * - MUST NOT send `announcement_signatures` messages until `funding_locked`
+ *   has been sent AND the funding transaction has at least six confirmations.
+ */
+#define ANNOUNCE_MIN_DEPTH 6
+
+#endif /* LIGHTNING_GOSSIPD_GOSSIP_CONSTANTS_H */
diff --git a/gossipd/routing.h b/gossipd/routing.h
index cc6257756..83ea09aa6 100644
--- a/gossipd/routing.h
+++ b/gossipd/routing.h
@@ -6,21 +6,11 @@
 #include <ccan/htable/htable_type.h>
 #include <ccan/time/time.h>
 #include <gossipd/broadcast.h>
+#include <gossipd/gossip_constants.h>
 #include <gossipd/gossip_store.h>
 #include <wire/gen_onion_wire.h>
 #include <wire/wire.h>
 
-#define ROUTING_MAX_HOPS 20
-/* BOLT #7:
- *
- * The `flags` bitfield...individual bits:
- *...
- * | 0             | `direction` | Direction this update refers to. |
- * | 1             | `disable`   | Disable the channel.             |
- */
-#define ROUTING_FLAGS_DIRECTION (1 << 0)
-#define ROUTING_FLAGS_DISABLED  (1 << 1)
-
 struct half_chan {
 	/* Cached `channel_update` which initialized below (or NULL) */
 	const u8 *channel_update;
diff --git a/lightningd/channel_control.c b/lightningd/channel_control.c
index 6bc694e7c..7d5905710 100644
--- a/lightningd/channel_control.c
+++ b/lightningd/channel_control.c
@@ -2,6 +2,7 @@
 #include <ccan/fdpass/fdpass.h>
 #include <channeld/gen_channel_wire.h>
 #include <errno.h>
+#include <gossipd/gossip_constants.h>
 #include <hsmd/capabilities.h>
 #include <hsmd/gen_hsm_client_wire.h>
 #include <inttypes.h>
diff --git a/lightningd/peer_control.h b/lightningd/peer_control.h
index c87bed3f9..642fbc02b 100644
--- a/lightningd/peer_control.h
+++ b/lightningd/peer_control.h
@@ -14,8 +14,6 @@
 #include <wallet/wallet.h>
 #include <wire/peer_wire.h>
 
-#define ANNOUNCE_MIN_DEPTH 6
-
 struct crypto_state;
 
 struct peer {