cleanup: make 'u8 *features' and 'struct feature_set *fset' more expl…

…icit.

It's almost always "their_features" and "our_features" respectively, so
make those names clear.

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

channeld/channel_wire.csv

@@ -8,7 +8,7 @@
 # Begin!  (passes gossipd-client fd)
 msgtype,channel_init,1000
 msgdata,channel_init,chainparams,chainparams,
-msgdata,channel_init,feature_set,feature_set,
+msgdata,channel_init,our_features,feature_set,
 msgdata,channel_init,funding_txid,bitcoin_txid,
 msgdata,channel_init,funding_txout,u16,
 msgdata,channel_init,funding_satoshi,amount_sat,
@@ -64,8 +64,8 @@ msgdata,channel_init,init_peer_pkt_len,u16,
 msgdata,channel_init,init_peer_pkt,u8,init_peer_pkt_len
 msgdata,channel_init,reached_announce_depth,bool,
 msgdata,channel_init,last_remote_secret,secret,
-msgdata,channel_init,lflen,u16,
-msgdata,channel_init,localfeatures,u8,lflen
+msgdata,channel_init,flen,u16,
+msgdata,channel_init,their_features,u8,flen
 msgdata,channel_init,upfront_shutdown_script_len,u16,
 msgdata,channel_init,upfront_shutdown_script,u8,upfront_shutdown_script_len
 msgdata,channel_init,remote_ann_node_sig,?secp256k1_ecdsa_signature,

channeld/channeld.c

@@ -74,10 +74,10 @@ struct peer {
 	u64 next_index[NUM_SIDES];
 
 	/* Features peer supports. */
-	u8 *features;
+	u8 *their_features;
 
 	/* Features we support. */
-	struct feature_set *fset;
+	struct feature_set *our_features;
 
 	/* Tolerable amounts for feerate (only relevant for fundee). */
 	u32 feerate_min, feerate_max;
@@ -418,7 +418,9 @@ static void send_announcement_signatures(struct peer *peer)
 static u8 *create_channel_announcement(const tal_t *ctx, struct peer *peer)
 {
 	int first, second;
-	u8 *cannounce, *features = get_agreed_channelfeatures(tmpctx, peer->fset, peer->features);
+	u8 *cannounce, *features
+		= get_agreed_channelfeatures(tmpctx, peer->our_features,
+					     peer->their_features);
 
 	if (peer->channel_direction == 0) {
 		first = LOCAL;
@@ -2328,7 +2330,8 @@ static void peer_reconnect(struct peer *peer,
 	bool dataloss_protect, check_extra_fields;
 	const u8 **premature_msgs = tal_arr(peer, const u8 *, 0);
 
-	dataloss_protect = feature_negotiated(peer->fset, peer->features,
+	dataloss_protect = feature_negotiated(peer->our_features,
+					      peer->their_features,
 					      OPT_DATA_LOSS_PROTECT);
 
 	/* Both these options give us extra fields to check. */
@@ -3059,7 +3062,7 @@ static void init_channel(struct peer *peer)
 	msg = wire_sync_read(tmpctx, MASTER_FD);
 	if (!fromwire_channel_init(peer, msg,
 				   &chainparams,
-				   &peer->fset,
+				   &peer->our_features,
 				   &funding_txid, &funding_txout,
 				   &funding,
 				   &minimum_depth,
@@ -3105,7 +3108,7 @@ static void init_channel(struct peer *peer)
 				   &funding_signed,
 				   &peer->announce_depth_reached,
 				   &last_remote_per_commit_secret,
-				   &peer->features,
+				   &peer->their_features,
 				   &peer->remote_upfront_shutdown_script,
 				   &remote_ann_node_sig,
 				   &remote_ann_bitcoin_sig,

common/bolt11.c

@@ -489,7 +489,7 @@ static void shift_bitmap_down(u8 *bitmap, size_t bits)
  *  See [Feature Bits](#feature-bits).
  */
 static char *decode_9(struct bolt11 *b11,
-		      const struct feature_set *fset,
+		      const struct feature_set *our_features,
 		      struct hash_u5 *hu5,
 		      u5 **data, size_t *data_len,
 		      size_t data_length)
@@ -512,9 +512,10 @@ static char *decode_9(struct bolt11 *b11,
 	 * - if the `9` field contains unknown _even_ bits that are non-zero:
 	 *   - MUST fail the payment.
 	 */
-	/* We skip this check for the cli tool, which sets fset to NULL */
-	if (fset) {
-		badf = features_unsupported(fset, b11->features, BOLT11_FEATURE);
+	/* We skip this check for the cli tool, which sets our_features to NULL */
+	if (our_features) {
+		badf = features_unsupported(our_features,
+					    b11->features, BOLT11_FEATURE);
 		if (badf != -1)
 			return tal_fmt(b11, "9: unknown feature bit %i", badf);
 	}
@@ -545,7 +546,7 @@ struct bolt11 *new_bolt11(const tal_t *ctx,
 
 /* Decodes and checks signature; returns NULL on error. */
 struct bolt11 *bolt11_decode(const tal_t *ctx, const char *str,
-			     const struct feature_set *fset,
+			     const struct feature_set *our_features,
 			     const char *description, char **fail)
 {
 	char *hrp, *amountstr, *prefix;
@@ -740,7 +741,8 @@ struct bolt11 *bolt11_decode(const tal_t *ctx, const char *str,
 					   data_length);
 			break;
 		case '9':
-			problem = decode_9(b11, fset, &hu5, &data, &data_len,
+			problem = decode_9(b11, our_features, &hu5,
+					   &data, &data_len,
 					   data_length);
 			break;
 		case 's':

common/bolt11.h

@@ -80,7 +80,7 @@ struct bolt11 {
  * fset is NULL to accept any features (usually not desirable!).
  */
 struct bolt11 *bolt11_decode(const tal_t *ctx, const char *str,
-			     const struct feature_set *fset,
+			     const struct feature_set *our_features,
 			     const char *description, char **fail);
 
 /* Initialize an empty bolt11 struct with optional amount */

common/features.c

@@ -158,17 +158,17 @@ static void clear_feature_bit(u8 *features, u32 bit)
  *  it sets.
  */
 u8 *get_agreed_channelfeatures(const tal_t *ctx,
-			       const struct feature_set *ours,
-			       const u8 *theirfeatures)
+			       const struct feature_set *our_features,
+			       const u8 *their_features)
 {
-	u8 *f = tal_dup_talarr(ctx, u8, ours->bits[CHANNEL_FEATURE]);
+	u8 *f = tal_dup_talarr(ctx, u8, our_features->bits[CHANNEL_FEATURE]);
 	size_t max_len = 0;
 
 	/* Clear any features which they didn't offer too */
 	for (size_t i = 0; i < 8 * tal_count(f); i += 2) {
 		if (!feature_offered(f, i))
 			continue;
-		if (!feature_offered(theirfeatures, i)) {
+		if (!feature_offered(their_features, i)) {
 			clear_feature_bit(f, COMPULSORY_FEATURE(i));
 			clear_feature_bit(f, OPTIONAL_FEATURE(i));
 			continue;
@@ -197,11 +197,11 @@ bool feature_offered(const u8 *features, size_t f)
 		|| feature_is_set(features, OPTIONAL_FEATURE(f));
 }
 
-bool feature_negotiated(const struct feature_set *ours,
-			const u8 *lfeatures, size_t f)
+bool feature_negotiated(const struct feature_set *our_features,
+			const u8 *their_features, size_t f)
 {
-	return feature_offered(lfeatures, f)
-		&& feature_offered(ours->bits[INIT_FEATURE], f);
+	return feature_offered(their_features, f)
+		&& feature_offered(our_features->bits[INIT_FEATURE], f);
 }
 
 /**
@@ -215,7 +215,7 @@ bool feature_negotiated(const struct feature_set *ours,
  *
  * Returns -1 on success, or first unsupported feature.
  */
-static int all_supported_features(const struct feature_set *ours,
+static int all_supported_features(const struct feature_set *our_features,
 				  const u8 *bitmap,
 				  enum feature_place p)
 {
@@ -226,24 +226,25 @@ static int all_supported_features(const struct feature_set *ours,
 		if (!test_bit(bitmap, bitnum/8, bitnum%8))
 			continue;
 
-		if (feature_offered(ours->bits[p], bitnum))
+		if (feature_offered(our_features->bits[p], bitnum))
 			continue;
 
 		return bitnum;
 	}
 	return -1;
 }
 
-int features_unsupported(const struct feature_set *ours, const u8 *theirs,
+int features_unsupported(const struct feature_set *our_features,
+			 const u8 *their_features,
 			 enum feature_place p)
 {
 	/* BIT 2 would logically be "compulsory initial_routing_sync", but
 	 * that does not exist, so we special case it. */
-	if (feature_is_set(theirs,
+	if (feature_is_set(their_features,
 			   COMPULSORY_FEATURE(OPT_INITIAL_ROUTING_SYNC)))
 		return COMPULSORY_FEATURE(OPT_INITIAL_ROUTING_SYNC);
 
-	return all_supported_features(ours, theirs, p);
+	return all_supported_features(our_features, their_features, p);
 }
 
 static const char *feature_name(const tal_t *ctx, size_t f)
@@ -269,12 +270,12 @@ static const char *feature_name(const tal_t *ctx, size_t f)
 }
 
 const char **list_supported_features(const tal_t *ctx,
-				     const struct feature_set *ours)
+				     const struct feature_set *fset)
 {
 	const char **list = tal_arr(ctx, const char *, 0);
 
-	for (size_t i = 0; i < tal_bytelen(ours->bits[INIT_FEATURE]) * 8; i++) {
-		if (test_bit(ours->bits[INIT_FEATURE], i / 8, i % 8))
+	for (size_t i = 0; i < tal_bytelen(fset->bits[INIT_FEATURE]) * 8; i++) {
+		if (test_bit(fset->bits[INIT_FEATURE], i / 8, i % 8))
 			tal_arr_expand(&list, feature_name(list, i));
 	}
 

common/features.h

@@ -32,24 +32,25 @@ bool feature_set_or(struct feature_set *a,
 
 /* Returns -1 if we're OK with all these offered features, otherwise first
  * unsupported (even) feature. */
-int features_unsupported(const struct feature_set *ours, const u8 *theirs,
+int features_unsupported(const struct feature_set *our_features,
+			 const u8 *their_features,
 			 enum feature_place p);
 
 /* For the features in channel_announcement */
 u8 *get_agreed_channelfeatures(const tal_t *ctx,
-			       const struct feature_set *ours,
+			       const struct feature_set *our_features,
 			       const u8 *theirfeatures);
 
 /* Is this feature bit requested? (Either compulsory or optional) */
 bool feature_offered(const u8 *features, size_t f);
 
 /* Was this feature bit offered by them and us? */
-bool feature_negotiated(const struct feature_set *ours,
-			const u8 *features, size_t f);
+bool feature_negotiated(const struct feature_set *our_features,
+			const u8 *their_features, size_t f);
 
 /* Return a list of what (init) features we advertize. */
 const char **list_supported_features(const tal_t *ctx,
-				     const struct feature_set *ours);
+				     const struct feature_set *fset);
 
 /* Low-level helpers to deal with big-endian bitfields. */
 bool feature_is_set(const u8 *features, size_t bit);

connectd/connect_wire.csv

@@ -6,7 +6,7 @@
 
 msgtype,connectctl_init,2000
 msgdata,connectctl_init,chainparams,chainparams,
-msgdata,connectctl_init,feature_set,feature_set,
+msgdata,connectctl_init,our_features,feature_set,
 msgdata,connectctl_init,id,node_id,
 msgdata,connectctl_init,num_wireaddrs,u16,
 msgdata,connectctl_init,wireaddrs,wireaddr_internal,num_wireaddrs