df: rename 'funder' to 'opener'

Previously we've used the term 'funder' to refer to the peer
paying the fees for a transaction; v2 of openchannel will make
this no longer true. Instead we rename this to 'opener', or the
peer sending the 'open_channel' message, since this will be universally
true in a dual-funding world.

common/fee_states.c

@@ -6,24 +6,24 @@
 
 /* If we're the finder, it's like an HTLC we added, if they are, it's like
  * a HTLC they added. */
-enum htlc_state first_fee_state(enum side funder)
+enum htlc_state first_fee_state(enum side opener)
 {
-	if (funder == LOCAL)
+	if (opener == LOCAL)
 		return SENT_ADD_HTLC;
 	else
 		return RCVD_ADD_HTLC;
 }
 
-enum htlc_state last_fee_state(enum side funder)
+enum htlc_state last_fee_state(enum side opener)
 {
-	if (funder == LOCAL)
+	if (opener == LOCAL)
 		return SENT_ADD_ACK_REVOCATION;
 	else
 		return RCVD_ADD_ACK_REVOCATION;
 }
 
 struct fee_states *new_fee_states(const tal_t *ctx,
-				  enum side funder,
+				  enum side opener,
 				  const u32 *feerate_per_kw)
 {
 	struct fee_states *fee_states = tal(ctx, struct fee_states);
@@ -32,7 +32,7 @@ struct fee_states *new_fee_states(const tal_t *ctx,
 	for (size_t i = 0; i < ARRAY_SIZE(fee_states->feerate); i++)
 		fee_states->feerate[i] = NULL;
 	if (feerate_per_kw)
-		fee_states->feerate[last_fee_state(funder)]
+		fee_states->feerate[last_fee_state(opener)]
 			= tal_dup(fee_states, u32, feerate_per_kw);
 	return fee_states;
 }
@@ -54,12 +54,12 @@ struct fee_states *dup_fee_states(const tal_t *ctx,
 }
 
 u32 get_feerate(const struct fee_states *fee_states,
-		enum side funder,
+		enum side opener,
 		enum side side)
 {
 	/* The first non-NULL feerate committed to this side is current */
-	for (enum htlc_state i = first_fee_state(funder);
-	     i <= last_fee_state(funder);
+	for (enum htlc_state i = first_fee_state(opener);
+	     i <= last_fee_state(opener);
 	     i++) {
 		if (!fee_states->feerate[i])
 			continue;
@@ -73,10 +73,10 @@ u32 get_feerate(const struct fee_states *fee_states,
 }
 
 void start_fee_update(struct fee_states *fee_states,
-		      enum side funder,
+		      enum side opener,
 		      u32 feerate_per_kw)
 {
-	enum htlc_state start = first_fee_state(funder);
+	enum htlc_state start = first_fee_state(opener);
 
 	/* BOLT #2:
 	 * Unlike an HTLC, `update_fee` is never closed but simply replaced.
@@ -135,11 +135,11 @@ void towire_fee_states(u8 **pptr, const struct fee_states *fee_states)
 	}
 }
 
-/* FIXME: we don't know funder inside fromwire_fee_states, so can't do
+/* FIXME: we don't know opener inside fromwire_fee_states, so can't do
  * this there :( */
-bool fee_states_valid(const struct fee_states *fee_states, enum side funder)
+bool fee_states_valid(const struct fee_states *fee_states, enum side opener)
 {
-	return fee_states->feerate[last_fee_state(funder)] != NULL;
+	return fee_states->feerate[last_fee_state(opener)] != NULL;
 }
 
 static const char *fmt_fee_states(const tal_t *ctx,

common/fee_states.h

@@ -18,11 +18,11 @@ struct fee_states {
 /**
  * new_fee_states: Initialize a fee_states structure as at open-of-channel.
  * @ctx: the tal ctx to allocate off
- * @funder: which side funded the channel (and thus, proposes fee updates).
+ * @opener: which side opened the channel (and thus, proposes fee updates).
  * @feerate_per_kw: the initial feerate (if any).
  */
 struct fee_states *new_fee_states(const tal_t *ctx,
-				  enum side funder,
+				  enum side opener,
 				  const u32 *feerate_per_kw);
 
 /**
@@ -36,33 +36,33 @@ struct fee_states *dup_fee_states(const tal_t *ctx,
 /**
  * get_feerate: Get the current feerate
  * @fee_states: the fee state machine
- * @funder: which side funded the channel (and thus, proposes fee updates).
+ * @opener: which side opened the channel (and thus, proposes fee updates).
  * @side: which side to get the feerate for
  */
 u32 get_feerate(const struct fee_states *fee_states,
-		enum side funder,
+		enum side opener,
 		enum side side);
 
 /**
  * first_fee_state: get the initial fee state.
- * @funder: which side funded the channel (and thus, proposes fee updates).
+ * @opener: which side opened the channel (and thus, proposes fee updates).
  */
-enum htlc_state first_fee_state(enum side funder);
+enum htlc_state first_fee_state(enum side opener);
 
 /**
  * last_fee_state: get the final fee state.
- * @funder: which side funded the channel (and thus, proposes fee updates).
+ * @opener: which side opened the channel (and thus, proposes fee updates).
  */
-enum htlc_state last_fee_state(enum side funder);
+enum htlc_state last_fee_state(enum side opener);
 
 /**
  * start_fee_update: feed a new fee update into state machine.
  * @fee_states: the fee state machine
- * @funder: which side funded the channel (and thus, proposes fee updates).
+ * @opener: which side opened the channel (and thus, proposes fee updates).
  * @feerate_per_kw: the new feerate.
  */
 void start_fee_update(struct fee_states *fee_states,
-		      enum side funder,
+		      enum side opener,
 		      u32 feerate_per_kw);
 
 /**
@@ -82,7 +82,7 @@ struct fee_states *fromwire_fee_states(const tal_t *ctx,
 				       const u8 **cursor, size_t *max);
 
 /**
- * Is this fee_state struct valid for this funding side?
+ * Is this fee_state struct valid for this side?
  */
-bool fee_states_valid(const struct fee_states *fee_states, enum side funder);
+bool fee_states_valid(const struct fee_states *fee_states, enum side opener);
 #endif /* LIGHTNING_COMMON_FEE_STATES_H */

common/initial_channel.c

@@ -24,7 +24,7 @@ struct channel *new_initial_channel(const tal_t *ctx,
 				    const struct pubkey *local_funding_pubkey,
 				    const struct pubkey *remote_funding_pubkey,
 				    bool option_static_remotekey,
-				    enum side funder)
+				    enum side opener)
 {
 	struct channel *channel = tal(ctx, struct channel);
 	struct amount_msat remote_msatoshi;
@@ -37,7 +37,7 @@ struct channel *new_initial_channel(const tal_t *ctx,
 				 channel->funding, local_msatoshi))
 		return tal_free(channel);
 
-	channel->funder = funder;
+	channel->opener = opener;
 	channel->config[LOCAL] = *local;
 	channel->config[REMOTE] = *remote;
 	channel->funding_pubkey[LOCAL] = *local_funding_pubkey;
@@ -58,8 +58,8 @@ struct channel *new_initial_channel(const tal_t *ctx,
 	channel->basepoints[REMOTE] = *remote_basepoints;
 
 	channel->commitment_number_obscurer
-		= commit_number_obscurer(&channel->basepoints[funder].payment,
-					 &channel->basepoints[!funder].payment);
+		= commit_number_obscurer(&channel->basepoints[opener].payment,
+					 &channel->basepoints[!opener].payment);
 
 	channel->option_static_remotekey = option_static_remotekey;
 	return channel;
@@ -95,7 +95,7 @@ struct bitcoin_tx *initial_channel_tx(const tal_t *ctx,
 				 &channel->funding_txid,
 				 channel->funding_txout,
 				 channel->funding,
-				 channel->funder,
+				 channel->opener,
 				 /* They specify our to_self_delay and v.v. */
 				 channel->config[!side].to_self_delay,
 				 &keyset,
@@ -111,7 +111,7 @@ struct bitcoin_tx *initial_channel_tx(const tal_t *ctx,
 
 u32 channel_feerate(const struct channel *channel, enum side side)
 {
-	return get_feerate(channel->fee_states, channel->funder, side);
+	return get_feerate(channel->fee_states, channel->opener, side);
 }
 
 static char *fmt_channel_view(const tal_t *ctx, const struct channel_view *view)
@@ -128,12 +128,12 @@ static char *fmt_channel_view(const tal_t *ctx, const struct channel_view *view)
 static char *fmt_channel(const tal_t *ctx, const struct channel *channel)
 {
 	return tal_fmt(ctx, "{ funding=%s,"
-		       " funder=%s,"
+		       " opener=%s,"
 		       " local=%s,"
 		       " remote=%s }",
 		       type_to_string(tmpctx, struct amount_sat,
 				      &channel->funding),
-		       side_to_str(channel->funder),
+		       side_to_str(channel->opener),
 		       fmt_channel_view(ctx, &channel->view[LOCAL]),
 		       fmt_channel_view(ctx, &channel->view[REMOTE]));
 }

common/initial_channel.h

@@ -39,7 +39,7 @@ struct channel {
 	u32 minimum_depth;
 
 	/* Who is paying fees. */
-	enum side funder;
+	enum side opener;
 
 	/* Limits and settings on this channel. */
 	struct channel_config config[NUM_SIDES];
@@ -78,7 +78,7 @@ struct channel {
  * @remote_basepoints: remote basepoints.
  * @local_fundingkey: local funding key
  * @remote_fundingkey: remote funding key
- * @funder: which side initiated it.
+ * @opener: which side initiated it.
  *
  * Returns channel, or NULL if malformed.
  */
@@ -96,7 +96,7 @@ struct channel *new_initial_channel(const tal_t *ctx,
 				    const struct pubkey *local_funding_pubkey,
 				    const struct pubkey *remote_funding_pubkey,
 				    bool option_static_remotekey,
-				    enum side funder);
+				    enum side opener);
 
 
 /**

common/initial_commit_tx.c

@@ -30,22 +30,22 @@ u64 commit_number_obscurer(const struct pubkey *opener_payment_basepoint,
 	return be64_to_cpu(obscurer);
 }
 
-bool try_subtract_fee(enum side funder, enum side side,
+bool try_subtract_fee(enum side opener, enum side side,
 		      struct amount_sat base_fee,
 		      struct amount_msat *self,
 		      struct amount_msat *other)
 {
-	struct amount_msat *funder_amount;
+	struct amount_msat *opener_amount;
 
-	if (funder == side)
-		funder_amount = self;
+	if (opener == side)
+		opener_amount = self;
 	else
-		funder_amount = other;
+		opener_amount = other;
 
-	if (amount_msat_sub_sat(funder_amount, *funder_amount, base_fee))
+	if (amount_msat_sub_sat(opener_amount, *opener_amount, base_fee))
 		return true;
 
-	*funder_amount = AMOUNT_MSAT(0);
+	*opener_amount = AMOUNT_MSAT(0);
 	return false;
 }
 
@@ -62,7 +62,7 @@ struct bitcoin_tx *initial_commit_tx(const tal_t *ctx,
 				     const struct bitcoin_txid *funding_txid,
 				     unsigned int funding_txout,
 				     struct amount_sat funding,
-				     enum side funder,
+				     enum side opener,
 				     u16 to_self_delay,
 				     const struct keyset *keyset,
 				     u32 feerate_per_kw,
@@ -104,7 +104,7 @@ struct bitcoin_tx *initial_commit_tx(const tal_t *ctx,
 	 * 3. Subtract this base fee from the funder (either `to_local` or
 	 * `to_remote`), with a floor of 0 (see [Fee Payment](#fee-payment)).
 	 */
-	if (!try_subtract_fee(funder, side, base_fee, &self_pay, &other_pay)) {
+	if (!try_subtract_fee(opener, side, base_fee, &self_pay, &other_pay)) {
 		/* BOLT #2:
 		 *
 		 * The receiving node MUST fail the channel if:

common/initial_commit_tx.h

@@ -76,7 +76,7 @@ static inline struct amount_sat commit_tx_base_fee(u32 feerate_per_kw,
  * initial_commit_tx: create (unsigned) commitment tx to spend the funding tx output
  * @ctx: context to allocate transaction and @htlc_map from.
  * @funding_txid, @funding_out, @funding: funding outpoint.
- * @funder: is the LOCAL or REMOTE paying the fee?
+ * @opener: is the LOCAL or REMOTE paying the fee?
  * @keyset: keys derived for this commit tx.
  * @feerate_per_kw: feerate to use
  * @dust_limit: dust limit below which to trim outputs.
@@ -95,7 +95,7 @@ struct bitcoin_tx *initial_commit_tx(const tal_t *ctx,
 				     const struct bitcoin_txid *funding_txid,
 				     unsigned int funding_txout,
 				     struct amount_sat funding,
-				     enum side funder,
+				     enum side opener,
 				     u16 to_self_delay,
 				     const struct keyset *keyset,
 				     u32 feerate_per_kw,
@@ -107,8 +107,8 @@ struct bitcoin_tx *initial_commit_tx(const tal_t *ctx,
 				     enum side side,
 				     char** err_reason);
 
-/* try_subtract_fee - take away this fee from the funder (and return true), or all if insufficient (and return false). */
-bool try_subtract_fee(enum side funder, enum side side,
+/* try_subtract_fee - take away this fee from the opener (and return true), or all if insufficient (and return false). */
+bool try_subtract_fee(enum side opener, enum side side,
 		      struct amount_sat base_fee,
 		      struct amount_msat *self,
 		      struct amount_msat *other);