gossip_store: remove redundant copy_message.

The single caller can easily use transfer_store_msg instead.

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

gossipd/gossip_store.c

@@ -106,47 +106,56 @@ struct gossip_store *gossip_store_new(struct routing_state *rstate)
 	return gs;
 }
 
-/* Copy a whole message from one gossip_store to another.  Returns
- * total msg length including header, or 0 on error. */
-static size_t copy_message(int in_fd, int out_fd, unsigned offset)
+/* Returns bytes transferred, or 0 on error */
+static size_t transfer_store_msg(int from_fd, size_t from_off, int to_fd,
+				 int *type)
 {
-	beint32_t belen, becsum;
+	beint32_t hdr[2];
 	u32 msglen;
 	u8 *msg;
+	const u8 *p;
+	size_t tmplen;
 
-	/* FIXME: optimize both read and allocation */
-	if (lseek(in_fd, offset, SEEK_SET) < 0
-	    || read(in_fd, &belen, sizeof(belen)) != sizeof(belen)
-	    || read(in_fd, &becsum, sizeof(becsum)) != sizeof(becsum)) {
-		status_broken("Failed reading header from to gossip store @%u"
+	*type = -1;
+	if (pread(from_fd, hdr, sizeof(hdr), from_off) != sizeof(hdr)) {
+		status_broken("Failed reading header from to gossip store @%zu"
 			      ": %s",
-			      offset, strerror(errno));
+			      from_off, strerror(errno));
 		return 0;
 	}
 
-	msglen = be32_to_cpu(belen);
-	msg = tal_arr(NULL, u8, sizeof(belen) + sizeof(becsum) + msglen);
-	memcpy(msg, &belen, sizeof(belen));
-	memcpy(msg + sizeof(belen), &becsum, sizeof(becsum));
-	if (read(in_fd, msg + sizeof(belen) + sizeof(becsum), msglen)
+	msglen = be32_to_cpu(hdr[0]);
+	if (msglen & GOSSIP_STORE_LEN_DELETED_BIT) {
+		status_broken("Can't transfer deleted msg from gossip store @%zu",
+			      from_off);
+		return 0;
+	}
+
+	/* FIXME: Reuse buffer? */
+	msg = tal_arr(tmpctx, u8, sizeof(hdr) + msglen);
+	memcpy(msg, hdr, sizeof(hdr));
+	if (pread(from_fd, msg + sizeof(hdr), msglen, from_off + sizeof(hdr))
 	    != msglen) {
-		status_broken("Failed reading %u from to gossip store @%u"
+		status_broken("Failed reading %u from to gossip store @%zu"
 			      ": %s",
-			      msglen, offset, strerror(errno));
-		tal_free(msg);
+			      msglen, from_off, strerror(errno));
 		return 0;
 	}
 
-	if (write(out_fd, msg, msglen + sizeof(belen) + sizeof(becsum))
-	    != msglen + sizeof(belen) + sizeof(becsum)) {
+	if (write(to_fd, msg, msglen + sizeof(hdr)) != msglen + sizeof(hdr)) {
 		status_broken("Failed writing to gossip store: %s",
 			      strerror(errno));
-		tal_free(msg);
 		return 0;
 	}
 
+	/* Can't use peektype here, since we have header on front */
+	p = msg + sizeof(hdr);
+	tmplen = msglen;
+	*type = fromwire_u16(&p, &tmplen);
+	if (!p)
+		*type = -1;
 	tal_free(msg);
-	return msglen + sizeof(belen) + sizeof(becsum);
+	return sizeof(hdr) + msglen;
 }
 
 /* Local unannounced channels don't appear in broadcast map, but we need to
@@ -177,12 +186,15 @@ static bool add_local_unnannounced(int in_fd, int out_fd,
 
 		for (size_t i = 0; i < 2; i++) {
 			size_t len_with_header;
+			int type;
 
 			if (!is_halfchan_defined(&c->half[i]))
 				continue;
 
-			len_with_header = copy_message(in_fd, out_fd,
-						       c->half[i].bcast.index);
+			len_with_header = transfer_store_msg(in_fd,
+							     c->half[i].bcast.index,
+							     out_fd,
+							     &type);
 			if (!len_with_header)
 				return false;
 
@@ -195,58 +207,6 @@ static bool add_local_unnannounced(int in_fd, int out_fd,
 	return true;
 }
 
-/* Returns bytes transferred, or 0 on error */
-static size_t transfer_store_msg(int from_fd, size_t from_off, int to_fd,
-				 int *type)
-{
-	beint32_t hdr[2];
-	u32 msglen;
-	u8 *msg;
-	const u8 *p;
-	size_t tmplen;
-
-	*type = -1;
-	if (pread(from_fd, hdr, sizeof(hdr), from_off) != sizeof(hdr)) {
-		status_broken("Failed reading header from to gossip store @%zu"
-			      ": %s",
-			      from_off, strerror(errno));
-		return 0;
-	}
-
-	msglen = be32_to_cpu(hdr[0]);
-	if (msglen & GOSSIP_STORE_LEN_DELETED_BIT) {
-		status_broken("Can't transfer deleted msg from gossip store @%zu",
-			      from_off);
-		return 0;
-	}
-
-	/* FIXME: Reuse buffer? */
-	msg = tal_arr(tmpctx, u8, sizeof(hdr) + msglen);
-	memcpy(msg, hdr, sizeof(hdr));
-	if (pread(from_fd, msg + sizeof(hdr), msglen, from_off + sizeof(hdr))
-	    != msglen) {
-		status_broken("Failed reading %u from to gossip store @%zu"
-			      ": %s",
-			      msglen, from_off, strerror(errno));
-		return 0;
-	}
-
-	if (write(to_fd, msg, msglen + sizeof(hdr)) != msglen + sizeof(hdr)) {
-		status_broken("Failed writing to gossip store: %s",
-			      strerror(errno));
-		return 0;
-	}
-
-	/* Can't use peektype here, since we have header on front */
-	p = msg + sizeof(hdr);
-	tmplen = msglen;
-	*type = fromwire_u16(&p, &tmplen);
-	if (!p)
-		*type = -1;
-	tal_free(msg);
-	return sizeof(hdr) + msglen;
-}
-
 /**
  * Rewrite the on-disk gossip store, compacting it along the way
  *