closingd: use common/read_peer_msg.

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

closingd/Makefile

@@ -55,6 +55,7 @@ CLOSINGD_COMMON_OBJS :=				\
 	common/peer_failed.o			\
 	common/permute_tx.o			\
 	common/ping.o				\
+	common/read_peer_msg.o			\
 	common/status.o				\
 	common/subdaemon.o			\
 	common/type_to_string.o			\

closingd/closing.c

@@ -6,7 +6,7 @@
 #include <common/derive_basepoints.h>
 #include <common/htlc.h>
 #include <common/peer_failed.h>
-#include <common/ping.h>
+#include <common/read_peer_msg.h>
 #include <common/status.h>
 #include <common/subdaemon.h>
 #include <common/type_to_string.h>
@@ -83,88 +83,18 @@ static u64 one_towards(u64 target, u64 value)
 	return value;
 }
 
-static void handle_ping(const u8 *msg,
+/* Handle random messages we might get, returning the first non-handled one. */
+static u8 *closing_read_peer_msg(const tal_t *ctx,
 				 struct crypto_state *cs,
-			const struct channel_id *our_channel_id)
-{
-	u8 *pong;
-
-	if (!check_ping_make_pong(msg, msg, &pong))
-		peer_failed(PEER_FD, cs, our_channel_id, "Bad ping");
-
-	status_trace("Got ping, sending %s", pong ?
-		     wire_type_name(fromwire_peektype(pong))
-		     : "nothing");
-
-	if (pong && !sync_crypto_write(cs, PEER_FD, take(pong)))
-		status_failed(STATUS_FAIL_PEER_IO,
-			      "Failed writing pong: %s", strerror(errno));
-}
-
-/* Handle random messages we might get, returning NULL if we handled it. */
-static u8 *read_peer_msg(const tal_t *ctx,
-			 struct crypto_state *cs,
-			 const struct channel_id *our_channel_id)
+				 const struct channel_id *channel)
 {
 	u8 *msg;
-	struct channel_id channel_id;
-
-	msg = sync_crypto_read(ctx, cs, PEER_FD);
-	if (!msg)
-		status_failed(STATUS_FAIL_PEER_IO,
-			      "Failed reading from peer: %s", strerror(errno));
-
-	if (is_gossip_msg(msg)) {
-		/* Forward to gossip daemon */
-		wire_sync_write(GOSSIP_FD, take(msg));
-		return NULL;
-	}
 
-	if (fromwire_peektype(msg) == WIRE_PING) {
-		handle_ping(msg, cs, our_channel_id);
-		return tal_free(msg);
-	}
-
-	if (fromwire_peektype(msg) == WIRE_ERROR) {
-		struct channel_id chanid;
-		char *err = sanitize_error(msg, msg, &chanid);
-
-		/* BOLT #1:
-		 *
-		 * The channel is referred to by `channel_id`, unless
-		 * `channel_id` is 0 (i.e. all bytes are 0), in which
-		 * case it refers to all channels.
-		 * ...
-
-		 * The receiving node:
-		 *   - upon receiving `error`:
-		 *    - MUST fail the channel referred to by the error
-		 *       message.
-		 *  - if no existing channel is referred to by the
-		 *    message:
-		 *    - MUST ignore the message.
-		 */
-		if (channel_id_is_all(&chanid)
-		    || structeq(&chanid, our_channel_id)) {
-			status_failed(STATUS_FAIL_PEER_BAD,
-				      "Received ERROR %s", err);
-		}
-		return tal_free(msg);
-	}
-
-	/* They're talking about a different channel? */
-	if (extract_channel_id(msg, &channel_id)
-	    && !structeq(&channel_id, our_channel_id)) {
-		status_trace("Rejecting %s for unknown channel_id %s",
-			     wire_type_name(fromwire_peektype(msg)),
-			     type_to_string(msg, struct channel_id,
-					    &channel_id));
-		sync_crypto_write(cs, PEER_FD,
-				  take(towire_errorfmt(msg, &channel_id,
-						       "Multiple channels"
-						       " unsupported")));
-		return tal_free(msg);
-	}
+	while ((msg = read_peer_msg(ctx, cs, channel,
+				    sync_crypto_write_arg,
+				    status_fail_io,
+				    status_fail_errpkt,
+				    NULL)) == NULL);
 
 	return msg;
 }
@@ -198,7 +128,7 @@ static void do_reconnect(struct crypto_state *cs,
 			      "Failed writing reestablish: %s", strerror(errno));
 
 	/* Wait for them to say something interesting */
-	while ((msg = read_peer_msg(tmpctx, cs, channel_id)) == NULL);
+	msg = closing_read_peer_msg(tmpctx, cs, channel_id);
 
 	if (!fromwire_channel_reestablish(msg, NULL, &their_channel_id,
 					  &next_local_commitment_number,
@@ -344,7 +274,7 @@ int main(int argc, char *argv[])
 
 	again:
 		/* Wait for them to say something interesting */
-		while ((msg = read_peer_msg(tmpctx, &cs, &channel_id)) == NULL);
+		msg = closing_read_peer_msg(tmpctx, &cs, &channel_id);
 
 		/* BOLT #2:
 		 *