gossipd/gossip_constants.h: Single place for BOLT constants.

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

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 > $@

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>

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))

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 */

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;

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>

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 {