devtools: enhance dump-gossipstore to show some details of messages.

diff --git a/devtools/dump-gossipstore.c b/devtools/dump-gossipstore.c
index 2d69b063..5280da86 100644
--- a/devtools/dump-gossipstore.c
+++ b/devtools/dump-gossipstore.c
@@ -3,6 +3,7 @@
 #include <ccan/err/err.h>
 #include <ccan/opt/opt.h>
 #include <common/gossip_store.h>
+#include <common/setup.h>
 #include <common/utils.h>
 #include <fcntl.h>
 #include <gossipd/gossip_store_wiregen.h>
@@ -14,6 +15,61 @@
 #define GSTORE_MAJOR 0
 #define GSTORE_MINOR 15
 
+static bool is_channel_announce(const u8 *msg, struct short_channel_id **scid)
+{
+	secp256k1_ecdsa_signature sig;
+	u8 *features;
+	struct bitcoin_blkid chain_hash;
+	struct node_id node;
+	struct pubkey key;
+
+	if (fromwire_peektype(msg) != WIRE_CHANNEL_ANNOUNCEMENT)
+		return false;
+
+	*scid = tal(msg, struct short_channel_id);
+	if (!fromwire_channel_announcement(msg, msg, &sig, &sig, &sig, &sig, &features,
+					   &chain_hash, *scid, &node, &node, &key, &key))
+		*scid = tal_free(*scid);
+	return true;
+}
+
+static bool is_channel_update(const u8 *msg, struct short_channel_id_dir **scidd)
+{
+	secp256k1_ecdsa_signature sig;
+	struct bitcoin_blkid chain_hash;
+	u32 u32val;
+	u8 message_flags, channel_flags;
+	u16 cltv_expiry_delta;
+	struct amount_msat msat;
+
+	if (fromwire_peektype(msg) != WIRE_CHANNEL_UPDATE)
+		return false;
+
+	*scidd = tal(msg, struct short_channel_id_dir);
+	if (fromwire_channel_update(msg, &sig, &chain_hash, &(*scidd)->scid, &u32val, &message_flags, &channel_flags, &cltv_expiry_delta, &msat, &u32val, &u32val, &msat))
+		(*scidd)->dir = (channel_flags & ROUTING_FLAGS_DIRECTION);
+	else
+		*scidd = tal_free(*scidd);
+	return true;
+}
+
+static bool is_node_announcement(const u8 *msg, struct node_id **node)
+{
+	secp256k1_ecdsa_signature sig;
+	u8 *u8arr;
+	u32 timestamp;
+	u8 rgb_color[3], alias[32];
+	struct tlv_node_ann_tlvs *tlvs;
+
+	if (fromwire_peektype(msg) != WIRE_NODE_ANNOUNCEMENT)
+		return false;
+
+	*node = tal(msg, struct node_id);
+	if (!fromwire_node_announcement(msg, msg, &sig, &u8arr, &timestamp, *node, rgb_color, alias, &u8arr, &tlvs))
+		*node = tal_free(*node);
+	return true;
+}
+
 int main(int argc, char *argv[])
 {
 	int fd;
@@ -23,7 +79,7 @@ int main(int argc, char *argv[])
 	bool print_deleted = false;
 	bool print_timestamp = false;
 
-	setup_locale();
+	common_setup(argv[0]);
 	opt_register_noarg("--print-deleted", opt_set_bool, &print_deleted,
 			   "Print deleted entries too");
 	opt_register_noarg("--print-timestamps", opt_set_bool, &print_timestamp,
@@ -64,7 +120,9 @@ int main(int argc, char *argv[])
 
 	while (read(fd, &hdr, sizeof(hdr)) == sizeof(hdr)) {
 		struct amount_sat sat;
-		struct short_channel_id scid;
+		struct short_channel_id scid, *scidptr;
+		struct short_channel_id_dir *sciddptr;
+		struct node_id *nodeptr;
 		u16 flags = be16_to_cpu(hdr.flags);
 		u16 msglen = be16_to_cpu(hdr.len);
 		u8 *msg, *inner;
@@ -95,17 +153,20 @@ int main(int argc, char *argv[])
 		if (fromwire_gossip_store_channel_amount(msg, &sat)) {
 			printf("channel_amount: %s\n",
 			       fmt_amount_sat(tmpctx, sat));
-		} else if (fromwire_peektype(msg) == WIRE_CHANNEL_ANNOUNCEMENT) {
-			printf("t=%u channel_announcement: %s\n",
+		} else if (is_channel_announce(msg, &scidptr)) {
+			printf("t=%u channel_announcement(%s): %s\n",
 			       be32_to_cpu(hdr.timestamp),
+			       scidptr ? fmt_short_channel_id(tmpctx, *scidptr) : "?",
 			       tal_hex(msg, msg));
-		} else if (fromwire_peektype(msg) == WIRE_CHANNEL_UPDATE) {
-			printf("t=%u channel_update: %s\n",
+		} else if (is_channel_update(msg, &sciddptr)) {
+			printf("t=%u channel_update(%s): %s\n",
 			       be32_to_cpu(hdr.timestamp),
+			       sciddptr ? fmt_short_channel_id_dir(tmpctx, sciddptr) : "?",
 			       tal_hex(msg, msg));
-		} else if (fromwire_peektype(msg) == WIRE_NODE_ANNOUNCEMENT) {
-			printf("t=%u node_announcement: %s\n",
+		} else if (is_node_announcement(msg, &nodeptr)) {
+			printf("t=%u node_announcement(%s): %s\n",
 			       be32_to_cpu(hdr.timestamp),
+			       nodeptr ? fmt_node_id(tmpctx, nodeptr) : "?",
 			       tal_hex(msg, msg));
 		} else if (fromwire_gossip_store_private_channel_obs(msg, msg, &sat,
 								 &inner)) {
@@ -131,5 +192,6 @@ int main(int argc, char *argv[])
 		off += sizeof(hdr) + msglen;
 		tal_free(msg);
 	}
+	common_shutdown();
 	return 0;
 }