Exclude uneconomical UTXOs from fundchannel

Author: AnthonyRonning

wallet/reservation.c

@@ -537,28 +537,45 @@ static struct command_result *json_fundpsbt(struct command *cmd,
 	/* We keep adding until we meet their output requirements. */
 	utxos = tal_arr(cmd, struct utxo *, 0);
 
+	/* We seperate out UTXOs to exclude if they are uneconomical */
+	struct utxo **uneconomical_utxos = tal_arr(cmd, struct utxo *, 0);
+
 	input = AMOUNT_SAT(0);
 	while (!inputs_sufficient(input, *amount, *feerate_per_kw, *weight,
 				  &diff)) {
 		struct utxo *utxo;
 		struct amount_sat fee;
 		u32 utxo_weight;
 
+
+		/* Merge the two lists for exclusion */
+		struct utxo **all_excluded = tal_arr(cmd, struct utxo *, 0);
+		for(size_t i = 0; i < tal_count(utxos); i++) {
+			tal_arr_expand(&all_excluded, utxos[i]);
+		}
+		for(size_t i = 0; i < tal_count(uneconomical_utxos); i++) {
+			tal_arr_expand(&all_excluded, uneconomical_utxos[i]);
+		}
+
 		utxo = wallet_find_utxo(utxos, cmd->ld->wallet,
 					current_height,
 					&diff,
 					*feerate_per_kw,
 					maxheight,
 					*nonwrapped,
-					cast_const2(const struct utxo **, utxos));
+					cast_const2(const struct utxo **, all_excluded));
+		tal_free(all_excluded);
+
 		if (utxo) {
 			utxo_weight = utxo_spend_weight(utxo,
 							*min_witness_weight);
 			fee = amount_tx_fee(*feerate_per_kw, utxo_weight);
 
 			/* Uneconomic to add this utxo, skip it */
-			if (!all && amount_sat_greater_eq(fee, utxo->amount))
+			if (!all && amount_sat_greater_eq(fee, utxo->amount)){
+				tal_arr_expand(&uneconomical_utxos, utxo);
 				continue;
+			}
 
 			tal_arr_expand(&utxos, utxo);
 
@@ -596,6 +613,8 @@ static struct command_result *json_fundpsbt(struct command *cmd,
 						     &diff));
 	}
 
+	tal_free(uneconomical_utxos);
+
 	if (all) {
 		/* We need to afford one non-dust output, at least. */
 		if (!inputs_sufficient(input, AMOUNT_SAT(0),