Zero fee htlc prep part #3: Block estimates, and the Return of RBF

.msggen.json

@@ -357,6 +357,8 @@
         },
         "FeeratesPerkb": {
             "Feerates.perkb.delayed_to_us": 6,
+            "Feerates.perkb.estimates[]": 9,
+            "Feerates.perkb.floor": 10,
             "Feerates.perkb.htlc_resolution": 7,
             "Feerates.perkb.max_acceptable": 2,
             "Feerates.perkb.min_acceptable": 1,
@@ -365,8 +367,15 @@
             "Feerates.perkb.penalty": 8,
             "Feerates.perkb.unilateral_close": 5
         },
+        "FeeratesPerkbEstimates": {
+            "Feerates.perkb.estimates[].blockcount": 1,
+            "Feerates.perkb.estimates[].feerate": 2,
+            "Feerates.perkb.estimates[].smoothed_feerate": 3
+        },
         "FeeratesPerkw": {
             "Feerates.perkw.delayed_to_us": 6,
+            "Feerates.perkw.estimates[]": 9,
+            "Feerates.perkw.floor": 10,
             "Feerates.perkw.htlc_resolution": 7,
             "Feerates.perkw.max_acceptable": 2,
             "Feerates.perkw.min_acceptable": 1,
@@ -375,6 +384,11 @@
             "Feerates.perkw.penalty": 8,
             "Feerates.perkw.unilateral_close": 5
         },
+        "FeeratesPerkwEstimates": {
+            "Feerates.perkw.estimates[].blockcount": 1,
+            "Feerates.perkw.estimates[].feerate": 2,
+            "Feerates.perkw.estimates[].smoothed_feerate": 3
+        },
         "FeeratesRequest": {
             "Feerates.style": 1
         },
@@ -1542,11 +1556,31 @@
         },
         "Feerates.perkb.delayed_to_us": {
             "added": "pre-v0.10.1",
+            "deprecated": "v23.05"
+        },
+        "Feerates.perkb.estimates[]": {
+            "added": "v23.05",
+            "deprecated": false
+        },
+        "Feerates.perkb.estimates[].blockcount": {
+            "added": "v23.05",
+            "deprecated": false
+        },
+        "Feerates.perkb.estimates[].feerate": {
+            "added": "v23.05",
+            "deprecated": false
+        },
+        "Feerates.perkb.estimates[].smoothed_feerate": {
+            "added": "v23.05",
+            "deprecated": false
+        },
+        "Feerates.perkb.floor": {
+            "added": "v23.05",
             "deprecated": false
         },
         "Feerates.perkb.htlc_resolution": {
             "added": "pre-v0.10.1",
-            "deprecated": false
+            "deprecated": "v23.05"
         },
         "Feerates.perkb.max_acceptable": {
             "added": "pre-v0.10.1",
@@ -1578,11 +1612,31 @@
         },
         "Feerates.perkw.delayed_to_us": {
             "added": "pre-v0.10.1",
+            "deprecated": "v23.05"
+        },
+        "Feerates.perkw.estimates[]": {
+            "added": "v23.05",
+            "deprecated": false
+        },
+        "Feerates.perkw.estimates[].blockcount": {
+            "added": "v23.05",
+            "deprecated": false
+        },
+        "Feerates.perkw.estimates[].feerate": {
+            "added": "v23.05",
+            "deprecated": false
+        },
+        "Feerates.perkw.estimates[].smoothed_feerate": {
+            "added": "v23.05",
+            "deprecated": false
+        },
+        "Feerates.perkw.floor": {
+            "added": "v23.05",
             "deprecated": false
         },
         "Feerates.perkw.htlc_resolution": {
             "added": "pre-v0.10.1",
-            "deprecated": false
+            "deprecated": "v23.05"
         },
         "Feerates.perkw.max_acceptable": {
             "added": "pre-v0.10.1",

bitcoin/feerate.c

@@ -1,8 +1,12 @@
 #include "config.h"
+#include <assert.h>
 #include <bitcoin/feerate.h>
 
 u32 feerate_from_style(u32 feerate, enum feerate_style style)
 {
+	/* Make sure it's called somewhere! */
+	assert(feerate_floor_check() == FEERATE_FLOOR);
+
 	switch (style) {
 	case FEERATE_PER_KSIPA:
 		return feerate;

bitcoin/feerate.h

@@ -39,7 +39,7 @@ enum feerate_style {
 	FEERATE_PER_KBYTE
 };
 
-static inline u32 feerate_floor(void)
+static inline u32 feerate_floor_check(void)
 {
 	/* Assert that bitcoind will see this as above minRelayTxFee */
 	BUILD_ASSERT(FEERATE_BITCOIND_SEES(FEERATE_FLOOR, MINIMUM_TX_WEIGHT)

channeld/watchtower.c

@@ -96,7 +96,9 @@ penalty_tx_create(const tal_t *ctx,
 
 	if (amount_sat_less(to_them_sats, min_out)) {
 		/* FIXME: We should use SIGHASH_NONE so others can take it */
-		fee = amount_tx_fee(feerate_floor(), weight);
+		/* We use the minimum possible fee here; if it doesn't
+		 * propagate, who cares? */
+		fee = amount_tx_fee(FEERATE_FLOOR, weight);
 	}
 
 	/* This can only happen if feerate_floor() is still too high; shouldn't

common/jsonrpc_errors.h

@@ -71,6 +71,7 @@ enum jsonrpc_errcode {
 
 	/* bitcoin-cli plugin errors */
 	BCLI_ERROR = 500,
+	BCLI_NO_FEE_ESTIMATES = 501,
 
 	/* Errors from `invoice` or `delinvoice` commands */
 	INVOICE_LABEL_ALREADY_EXISTS = 900,

common/utils.h

@@ -80,11 +80,22 @@ void clear_softref_(const tal_t *outer, size_t outersize, void **ptr);
  * Remove an element from an array
  *
  * This will shift the elements past the removed element, changing
- * their position in memory, so only use this for arrays of pointers.
+ * their position in memory, so only use this for simple arrays.
  */
 #define tal_arr_remove(p, n) tal_arr_remove_((p), sizeof(**p), (n))
 void tal_arr_remove_(void *p, size_t elemsize, size_t n);
 
+/**
+ * Insert an element in an array
+ */
+#define tal_arr_insert(p, n, v) \
+	do {								\
+		size_t n_ = tal_count(*(p));				\
+		tal_resize((p), n_+1);					\
+		memmove(*(p) + n + 1, *(p) + n, (n_ - n) * sizeof(**(p))); \
+		(*(p))[n] = (v);					\
+	} while(0)
+
 /* Check for valid UTF-8 */
 bool utf8_check(const void *buf, size_t buflen);