wire: move extract_channel_id to here.

It can be useful for other daemons.

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

lightningd/peer_control.c

@@ -445,33 +445,6 @@ bool unsupported_features(const u8 *gfeatures, const u8 *lfeatures)
 						 sizeof(supported_local_features));
 }
 
-/* Extract channel_id from various packets, return true if possible. */
-static bool extract_channel_id(const u8 *in_pkt, struct channel_id *channel_id)
-{
-	u64 ignored_u64;
-	u32 ignored_u32;
-	u16 ignored_u16;
-	u8 ignored_u8;
-	struct pubkey ignored_pubkey;
-	struct bitcoin_blkid ignored_chainhash;
-
-	if (fromwire_channel_reestablish(in_pkt, NULL, channel_id,
-					 &ignored_u64, &ignored_u64))
-		return true;
-	if (fromwire_open_channel(in_pkt, NULL, &ignored_chainhash,
-				  channel_id, &ignored_u64,
-				  &ignored_u64, &ignored_u64,
-				  &ignored_u64, &ignored_u64,
-				  &ignored_u64, &ignored_u32,
-				  &ignored_u16, &ignored_u16,
-				  &ignored_pubkey, &ignored_pubkey,
-				  &ignored_pubkey, &ignored_pubkey,
-				  &ignored_pubkey, &ignored_pubkey,
-				  &ignored_u8))
-		return true;
-	return false;
-}
-
 /**
  * peer_channel_new -- Instantiate a new channel for the given peer and save it
  *

wire/peer_wire.c

@@ -73,3 +73,30 @@ bool is_unknown_msg_discardable(const u8 *cursor)
 	enum wire_type t = fromwire_peektype(cursor);
 	return unknown_type(t) && (t & 1);
 }
+
+/* Extract channel_id from various packets, return true if possible. */
+bool extract_channel_id(const u8 *in_pkt, struct channel_id *channel_id)
+{
+	u64 ignored_u64;
+	u32 ignored_u32;
+	u16 ignored_u16;
+	u8 ignored_u8;
+	struct pubkey ignored_pubkey;
+	struct bitcoin_blkid ignored_chainhash;
+
+	if (fromwire_channel_reestablish(in_pkt, NULL, channel_id,
+					 &ignored_u64, &ignored_u64))
+		return true;
+	if (fromwire_open_channel(in_pkt, NULL, &ignored_chainhash,
+				  channel_id, &ignored_u64,
+				  &ignored_u64, &ignored_u64,
+				  &ignored_u64, &ignored_u64,
+				  &ignored_u64, &ignored_u32,
+				  &ignored_u16, &ignored_u16,
+				  &ignored_pubkey, &ignored_pubkey,
+				  &ignored_pubkey, &ignored_pubkey,
+				  &ignored_pubkey, &ignored_pubkey,
+				  &ignored_u8))
+		return true;
+	return false;
+}

wire/peer_wire.h

@@ -19,6 +19,9 @@ bool is_unknown_msg_discardable(const u8 *cursor);
 /* Return true if it's a gossip message. */
 bool is_gossip_msg(const u8 *cursor);
 
+/* Extract channel_id from various packets, return true if possible. */
+bool extract_channel_id(const u8 *in_pkt, struct channel_id *channel_id);
+
 /* BOLT #2:
  *
  * Only the least-significant bit of `channel_flags` is currently